1,453 results
Search Results
2. [Paper microphoretic study and anatomo-pathological study of an infectious syndrome in dogs responding serologically to a strain of Rickettsia psittaci].
- Author
-
GROULADE J, DRIEUX H, GROULADE P, and DRUFOVKA B
- Subjects
- Animals, Dogs, Chlamydia, Chlamydophila psittaci, Communicable Diseases, Dog Diseases, Rickettsia
- Published
- 1954
3. Improved lateral-flow immunoassays for chlamydia and immunoglobulin M by sequential rehydration of two-phase system components within a paper-based diagnostic.
- Author
-
Mosley, Garrett, Pereira, David, Han, Yue, Lee, So, Wu, Chloe, Wu, Benjamin, and Kamei, Daniel
- Subjects
- *
IMMUNOASSAY , *CHLAMYDIA , *IMMUNOGLOBULIN M , *POTASSIUM phosphates , *GOLD nanoparticles - Abstract
Frequent screening of at-risk individuals using paper-based point-of-care diagnostics is a promising method for attenuating the spread of chlamydia and HIV. However, such diagnostics typically suffer from limited sensitivity. The authors describe a method to improve the sensitivity of the lateral-flow immunoassay (LFA), in which the target molecules are thermodynamically concentrated using aqueous two-phase systems (ATPSs) to improve the detection limit. The novel concept of sequential ATPS component resolubilization within paper for both a PEG-potassium phosphate and a UCON-50-HB-5100-potassium phosphate system was established to provide a diagnostic tool which only requires the sample to be added without any sample preparation steps. The automated ATPS phase separation and concentration of the target into the leading phase within the paper matrix can be visually demonstrated due to the use of gold nanoparticles. The importance of resolubilization order of the dehydrated polymers and salts is discussed. The designs presented improve the detection limit of a conventional LFA setup for Chlamydia trachomatis bacteria (158 μg·mL) and human immunoglobulin M (IgM) antibodies (0.31 μg·mL) to 15.8 μg·mL and 0.031 μg·mL, respectively. This is a 10-fold detection limit improvement and results are available in 15 min. Compared to other methods that improve LFA sensitivity, this particular method does not require additional equipment, reagents, or sample preparation steps as all necessary components are embedded into the initial setup. Therefore, this advancement enables a more sensitive LFA that can be operated by untrained or minimally trained personnel, significantly expanding its applicability as a point-of-care test. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
4. Paper-based molecular diagnostic for Chlamydia trachomatis
- Author
-
Bertrand Lemieux, Huimin Kong, Natalia M. Rodriguez, Catherine M. Klapperich, Jacqueline C. Linnes, and Andy Fan
- Subjects
Chlamydia ,business.industry ,General Chemical Engineering ,Nanotechnology ,General Chemistry ,Paper based ,medicine.disease ,medicine.disease_cause ,Virology ,Visual detection ,medicine ,Chlamydia trachomatis ,business ,Point of care - Abstract
Herein we show the development of a minimally instrumented paper-based molecular diagnostic for point of care detection of sexually transmitted infections caused by Chlamydia trachomatis. This new diagnostic platform incorporates cell lysis, isothermal nucleic acid amplification, and lateral flow visual detection using only pressure and heat sources, eliminating the need for expensive laboratory equipment. This paper-based test can be performed in less than one hour and has a clinically relevant limit of detection that is 100× more sensitive than current rapid immunoassays used for chlamydia diagnosis.
- Published
- 2014
5. Utilization of L-cell nucleoside triphosphates by Chlamydia psittaci for ribonucleic acid synthesis.
- Author
-
Hatch TP
- Subjects
- Adenine metabolism, Adenosine Triphosphate metabolism, Animals, Carbon Radioisotopes, Chromatography, Paper, Electrophoresis, Polyacrylamide Gel, Guanosine metabolism, Guanosine Triphosphate metabolism, Mice, Phosphorus Radioisotopes, Tritium, Uridine metabolism, Chlamydia metabolism, Cytosine Nucleotides metabolism, L Cells metabolism, RNA, Bacterial biosynthesis, RNA, Ribosomal biosynthesis, Uracil Nucleotides metabolism
- Abstract
Long-term, 32-P-labeled L cells were infected with the obligately intracellular parasite Chlamydia psittaci (strain 6 BC). At 20 h postinfection, [3-H]uridine was added, and the infected cells were sampled at intervals for incorporation of the labels into the uridine triphosphate (UTP) and cytidine triphosphate (CTP) pools of the host L cell and the uridine monophosphate (UMP) and cytidine monophosphate (CMP) in 16S ribosomal ribonucleic acid (RNA) of the parasite. The specific activity of the nucleotides was calculated from the ratio of 3-H to 32-P counts in the nucleotides. The rate of approach to equilibrium labeling of UTP and CTP in L-cell pools and UMP and CMP in 16S RNA from the exogenous uridine label was determined from the increase in the ratios of the specific activities of CTP to UTP and CMP to UMP with time. The rate of approach to equilibrium CMP:UMP labeling of the 16S RNA of C. psittaci was consistent with the rate predicted from the kinetics of labeling of the CTP and UTP pools of the host L cell. In analogous experiments, the rate of approach to equilibrium guanosine monophosphate:adenosine monophosphate labeling of 16S RNA from an exogenous [14-C]adenine label was consistent with the rate predicted from the kinetics of labeling of the purine nucleoside triphosphate pool of the host cell. These results support the concept that members of the genus Chlamydia owe their obligate intracellular mode of reproduction to a requirement for energy intermediates which is fulfilled by the host cell. In addition, evidence was obtained that the total acid-soluble purine nucleoside triphosphate pool of L cells accurately represents the precursors of L-cell 18S ribosomal RNA.
- Published
- 1975
- Full Text
- View/download PDF
6. Immunochemical studies on chlamydial group antigen (presence of a 2-keto-3-deoxycarbohydrate as immunodominant group).
- Author
-
Dhir SP, Hakomori S, Kenny GE, and Grayston JT
- Subjects
- Antigens, Bacterial analysis, Caprylates, Carbohydrates analysis, Chromatography, Paper, Complement Fixation Tests, Hydrolysis, Immunodiffusion, Immunoelectrophoresis, Periodic Acid pharmacology, Salmonella immunology, Antigens analysis, Chlamydia immunology, Immunochemistry, Polysaccharides, Bacterial analysis
- Published
- 1972
7. Transaminase activity and other enzymatic reactions involving pyruvate and glutamate in Chlamydia (psittacosis-trachoma group).
- Author
-
Weiss E
- Subjects
- Carbon Isotopes, Chromatography, Paper, Glucose metabolism, Oxidoreductases metabolism, Carbon Dioxide biosynthesis, Chlamydia metabolism, Glutamates metabolism, Pyruvates metabolism, Transaminases metabolism
- Abstract
The agents of meningopneumonitis (MN) and of trachoma (TR) purified from chick embryo allantoic fluids and yolk sacs, respectively, were shown to produce CO(2) from the C(1) positions of pyruvate and glutamate, but not from the other carbon atoms. The reaction with pyruvate did not require did not require the addition of cofactors, but was stimulated to a small extent by alpha-lipoic acid and, in the case of TR, also by diphosphothiamine, and nicotinamide adenine dinucleotide (NAD). The reaction of MN with glutamate was greatly stimulated by the addition of NAD and pyruvate, and resulted in the accumulation of alanine. The reaction of TR with glutamate was also greatly enhanced by added NAD, but was not affected by added pyruvate. When eight intermediates of the citric acid cycle were added to MN cells incubated with glutamate-C(14), plus NAD and pyruvate, they reduced to varying degrees the evolution of C(14)O(2). It was shown by chromatography that the C(14) label extended to alpha-ketoglutarate and succinate, but not to fumarate and malate. A net gain in adenosine triphosphate could not be demonstrated in MN cells incubated with combined glutamate, pyruvate, oxaloacetate, and various cofactors. These results furnish additional examples of real or apparent gaps in enzyme sequences in Chlamydia.
- Published
- 1967
- Full Text
- View/download PDF
8. Introduction to papers from the third meeting on the Planctomycetes-Verrucomicrobia-Chlamydiae bacteria: new model organisms in the omics era
- Author
-
Damien P. Devos, Olga Maria Lage, and CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental
- Subjects
0301 basic medicine ,Microbial diversity ,030106 microbiology ,ved/biology.organism_classification_rank.species ,species identification ,Chlamydiae ,bacterium culture ,Computational biology ,peptidoglycan ,phylogeny ,ubiquitination ,Microbiology ,Planctomycetales ,Planctomyces ,03 medical and health sciences ,Verrucomicrobia ,Chlamydia ,Model organism ,Molecular Biology ,protein expression ,nonhuman ,Verrucomicrobium ,biology ,ved/biology ,Planctomycetes ,bacterium isolate ,species habitat ,General Medicine ,biology.organism_classification ,Omics ,030104 developmental biology ,Editorial ,priority journal ,microbial diversity ,physiology ,cytoplasm ,cell compartmentalization ,microbial community ,Bacteria ,cell density - Abstract
The Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) super-phylum contains, in addition to the three name-giving phyla, the Lentisphaerae and Kirimatiellaeota, as well as some uncultured candidate phyla, such as the Candidatus Omnitrophica. PVC bacteria have recently attracted attention from the scientific community for the peculiar characteristics that they display. For the third time, the PVC scientific community met recently at their bi-annual conference (http://pvcbacteria.org/pvcmeeting17/). In this special section, we would like to share some of the exciting results that were presented at this meeting.
- Published
- 2018
9. Expedited partner therapy for adolescents diagnosed with chlamydia or gonorrhea: a position paper of the Society for Adolescent Medicine
- Author
-
Diane M. Straub, Tonya Chaffee, Kanti R. Ford, Gale R. Burstein, Allison H. Eliscu, Matthew Hogben, Taraneh Shafii, and Jill S. Huppert
- Subjects
Adult ,Male ,medicine.medical_specialty ,Consensus ,Adolescent ,Gonorrhea ,Adolescent medicine ,Young Adult ,Adolescent Medicine ,medicine ,Humans ,Chlamydia ,business.industry ,Public Health, Environmental and Occupational Health ,Chlamydia Infections ,medicine.disease ,Psychiatry and Mental health ,Sexual Partners ,Family medicine ,Pediatrics, Perinatology and Child Health ,Physical therapy ,Position paper ,Female ,business ,Societies - Published
- 2009
10. Using computer-assisted survey instruments instead of paper and pencil increased completeness of self-administered sexual behavior questionnaires.
- Author
-
Spark, Simone, Lewis, Dyani, Vaisey, Alaina, Smyth, Eris, Wood, Anna, Temple-Smith, Meredith, Lorch, Rebecca, Guy, Rebecca, and Hocking, Jane
- Subjects
- *
HEALTH surveys , *DRUG administration , *HUMAN sexuality , *QUESTIONNAIRES , *MEDICAL equipment - Abstract
Objectives: To compare the data quality, logistics, and cost of a self-administered sexual behavior questionnaire administered either using a computer-assisted survey instrument (CASI) or by paper and pencil in a primary care clinic. Study Design and Setting: A self-administered sexual behavior questionnaire was administered to 16-29 year olds attending general practice. Questionnaires were administered by either paper and pencil (paper) or CASI. A personal digital assistant was used to selfadminister the CASI. Results: A total of 4,491 people completed the questionnaire, with 46.9% responses via CASI and 53.2% by paper. Completion of questions was greater for CASI than for paper for sexual behavior questions: number of sexual partners [odds ratio (OR), 6.85; 95% confidence interval (CI): 3.32, 14.11] and ever having had sex with a person of the same gender (OR, 2.89; 95% CI: 1.52, 5.49). The median number of questions answered was higher for CASI than for paper (17.6 vs. 17.2; P ! 0.01). CASI was cheaper to run at $8.18 per questionnaire compared with $11.83 for paper. Conclusion: Electronic devices using CASI are a tool that can increase participants' questionnaire responses and deliver more complete data for a sexual behavior questionnaire in primary care clinics. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
11. Gonorrhea and Chlamydia Cases Are Rising in the United States: Expedited Partner Therapy Might Help.
- Author
-
Nelson T, Nandwani J, and Johnson D
- Subjects
- Contact Tracing, Humans, Sexual Partners, United States epidemiology, Chlamydia, Chlamydia Infections drug therapy, Chlamydia Infections epidemiology, Chlamydia Infections prevention & control, Gonorrhea drug therapy, Gonorrhea epidemiology, Gonorrhea prevention & control
- Abstract
Competing Interests: Conflict of Interest and Sources of Funding: None declared.
- Published
- 2022
- Full Text
- View/download PDF
12. Implementation of a Learning Collaborative Model Increases Chlamydia Screening at 37 Family Planning Clinics: Lessons Learned From 3 Cohorts.
- Author
-
Quimby KD, Kawatu JE, Saul KM, and Schamus LA
- Subjects
- Family Planning Services, Female, Humans, Mass Screening, New York, United States, Chlamydia, Chlamydia Infections diagnosis
- Abstract
Background: Chlamydia is the most commonly reported notifiable condition in the United States. Chlamydia disproportionately impacts young women and women of color. Annual screening of sexually active women 24 years and younger is recommended., Methods: Between 2016 and 2019, we facilitated 3 learning collaboratives to increase chlamydia screening at a combined 37 family planning clinics funded by the Planned Parenthood Federation of America, the Office of Population Affairs in the Department of Health and Human Services, and the New York State Department of Health. We applied a consistent learning collaborative approach across the 3 cohorts. Participating clinics sought to improve the proportion of clients screened for chlamydia each month, implemented a standard set of recommended practices, attended virtual learning sessions, reported updates on quality improvement efforts and chlamydia screening data monthly, and provided qualitative feedback in an online final assessment., Results: Median screening rates increased by 11%, 22%, and 24% in the 3 collaboratives (P values of <0.01, 0.05, and 0.02, respectively). Increases were sustained after the collaboratives ended though the changes did not reach statistical significance. At least 75% of clinics increased screening rates in each collaborative. Clinics reported that adopting normalizing and opt-out language when counseling clients about screening was both feasible and effective, as was reducing missed opportunities for screening., Conclusions: Learning collaboratives consistently resulted in improvement across 3 cohorts and shed light on barriers and facilitators to screening in family planning settings. Public health practitioners are encouraged to draw on our results and lessons learned to promote screening.
- Published
- 2021
- Full Text
- View/download PDF
13. Republished paper: The POPI trial: what does it mean for chlamydia control now?
- Author
-
Nicola Low and Jane S Hocking
- Subjects
medicine.medical_specialty ,Chlamydia ,business.industry ,Incidence (epidemiology) ,Medical record ,MEDLINE ,General Medicine ,medicine.disease ,medicine.disease_cause ,Surgery ,Family medicine ,Pelvic inflammatory disease ,Epidemiology ,medicine ,Chlamydia trachomatis ,business ,Pelvic Infection - Abstract
The results of the Prevention Of Pelvic Infection (POPI) trial,1 published soon after criticism about the value for money of the chlamydia screening programme in England,2 should make us think even harder about how to investigate and control chlamydia and its associated morbidity. Should we be doing more of the same, but better? Should we be developing new approaches? Or do we need both? The innovative trial by Oakeshott et al in female college students in London provides new information about the effects on pelvic inflammatory disease (PID) of a single round of screening for Chlamydia trachomatis .1 By collecting specimens from all participants at baseline, Oakeshott and colleagues have provided the first data comparing the incidence of PID according to chlamydia infection status in women receiving immediate testing and treatment with those for whom testing and treatment were deferred by 12 months. The ethical decision to allow deferred testing is justified by the uncertainty about the incidence of PID in the community before the start of the trial, the low observed incidence in practice and the advice for all study participants about the availability of free chlamydia testing. The investigators randomised and followed 2529 women (mean age 20.9 years) and collected outcome data on 2377 (94%) from the women or their GPs. They obtained information from medical records of suspected PID cases and …
- Published
- 2010
- Full Text
- View/download PDF
14. 'Tissue paper sign': a highly specific marker of gonococcal urethritis in males
- Author
-
Shuen-Loong Tham, H. H. Tan, and W. P. Tan
- Subjects
Male ,medicine.medical_specialty ,Gonorrhea ,Chlamydia trachomatis ,medicine.disease_cause ,Clothing ,Cohort Studies ,Medicine ,Humans ,Urethritis ,Prospective Studies ,Singapore ,Chlamydia ,business.industry ,Public Health, Environmental and Occupational Health ,Exudates and Transudates ,Chlamydia Infections ,medicine.disease ,Genitourinary medicine ,Infectious Diseases ,Immunology ,Syphilis ,business ,Sign (mathematics) ,Gonococcal Urethritis - Published
- 2009
15. Novel typing scheme reveals emergence and genetic diversity of Chlamydia pecorum at the local management scale across two koala populations.
- Author
-
Fernandez CM, Krockenberger MB, Ho SYW, Crowther MS, Mella VSA, Jelocnik M, Wilmott L, and Higgins DP
- Subjects
- Animals, Genotype, New South Wales, Phylogeny, Phascolarctidae microbiology, Chlamydia genetics, Chlamydia classification, Chlamydia isolation & purification, Chlamydia Infections veterinary, Chlamydia Infections microbiology, Genetic Variation, Multilocus Sequence Typing
- Abstract
To overcome shortcomings in discriminating Chlamydia pecorum strains infecting the koala (Phascolarctos cinereus) at the local level, we developed a novel genotyping scheme for this pathogen to inform koala management at a fine-scale subpopulation level. We applied this scheme to two geographically distinct koala populations in New South Wales, Australia: the Liverpool Plains and the Southern Highlands to South-west Sydney (SHSWS). Our method provides greater resolution than traditional multi-locus sequence typing, and can be used to monitor strain emergence, movement, and divergence across a range of fragmented habitats. Within the Liverpool Plains population, suspected recent introduction of a novel strain was confirmed by an absence of genetic diversity at the earliest sampling events and limited diversity at recent sampling events. Across the partially fragmented agricultural landscape of the Liverpool Plains, diversity within a widespread sequence type suggests that this degree of fragmentation may hinder but not prevent spread. In the SHSWS population, our results suggest movement of a strain from the south, where diverse strains exist, into a previously Chlamydia-free area in the north, indicating the risk of expansion towards an adjacent Chlamydia-negative koala population in South-west Sydney. In the south of the SHSWS where koala subpopulations appear segregated, we found evidence of divergent strain evolution. Our tool can be used to infer the risks of strain introduction across fragmented habitats in population management, particularly through practices such as wildlife corridor constructions and translocations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
16. Genetic diversity of Chlamydia pecorum detected in sheep flocks from Mexico
- Author
-
M M, Limón-González, R, Hernández-Castro, F, Martínez-Hernández, J, Xicohtencatl-Cortes, H, Ramírez-Alvarez, E G, Palomares-Resendiz, and E, Díaz-Aparicio
- Subjects
Male ,Sheep ,Swine ,Genetic Variation ,Sheep Diseases ,Chlamydia Infections ,Bacterial, Fungal and Virus Molecular Biology - Research Paper ,Microbiology ,Mice ,RNA, Ribosomal, 23S ,Pregnancy ,RNA, Ribosomal, 16S ,Media Technology ,Animals ,Cattle ,Female ,Chlamydia ,Phascolarctidae ,Mexico - Abstract
Chlamydia pecorum, an obligate intracellular bacterium, is associated with reproductive and systemic diseases in sheep, goats, pigs, cattle, and koalas. The main conditions include polyarthritis, conjunctivitis, enteritis, pneumonia, encephalomyelitis, orchitis, placentitis, and abortion. Even though there are several studies showing that C. pecorum infections are widely spread in the world, in Mexico there are no reports. During 2016, as part of a sheep restocking program in Mexico, sheep were imported from New Zealand. Briefly after their arrival in the herds in the State of Mexico, these sheep presented abortions during the last third of gestation. A total of 62 sheep vaginal swabs that had presented abortion from different municipalities of the State of Mexico were collected. Bacterial isolation was performed using L929 mouse fibroblasts, and molecular identification was achieved by 23S rRNA (Chlamydiaceae family) and ompA gene (species-specific) real-time polymerase chain reaction (PCR). In addition, the 16S rRNA subunit and ompA gene were amplified and sequenced. Seven of 62 samples were positive for C. pecorum by bacterial isolation, 23S rRNA, and ompA gene real-time PCR. The 16S rRNA subunit and ompA gene amplicons were purified and the nucleotide sequence was determined in both directions. The consensus sequences homology search was performed using BLASTn analysis and showed a 100% of homology with the C. pecorum 16S rRNA subunit and 99% with the C. pecorum ompA gene. The population structure analyses using ompA gene demonstrated 15 genetic populations or clusters of 198 sequences from GenBank and our sequences were in a particular genetic structure corresponding to genotype “O.” Herein, we describe the presence of C. pecorum in sheep imported from New Zealand into Mexico. Genetic analysis of the ompA gene showed that the isolates belong to genotype O and are related to strains isolated from sheep, cattle, and koalas. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-022-00682-9.
- Published
- 2022
17. Alcohol use, cigarette smoking, vaping and number of sexual partners: A cross‐sectional study of sexually active, ethnically diverse, inner city adolescents
- Author
-
Agata Lesniewska, Sarah Kerry-Barnard, Pippa Oakeshott, Rosalie Bartholomew, Rachel Phillips, Nicholas Beckley-Hoelscher, Freya Yoward, Charlotte Fleming, and Fiona Reid
- Subjects
Male ,Medicine (General) ,Adolescent ,Alcohol Drinking ,Cross-sectional study ,Ethnic group ,cigarette smoking ,Context (language use) ,1110 Nursing ,1117 Public Health and Health Services ,03 medical and health sciences ,0302 clinical medicine ,R5-920 ,risky behaviours ,medicine ,Humans ,030212 general & internal medicine ,adolescents ,Adverse effect ,Public, Environmental & Occupational Health ,Chlamydia ,Science & Technology ,business.industry ,alcohol ,030503 health policy & services ,Vaping ,Public Health, Environmental and Occupational Health ,Questionnaire ,medicine.disease ,Confidence interval ,Original Research Paper ,Health Care Sciences & Services ,Cross-Sectional Studies ,Sexual Partners ,Relationship education ,1701 Psychology ,Health Policy & Services ,sexual lifestyles ,Female ,Public Health ,Public aspects of medicine ,RA1-1270 ,0305 other medical science ,business ,Life Sciences & Biomedicine ,Original Research Papers ,Demography - Abstract
Context There are few UK data on the prevalence and clustering of risky behaviours in ethnically diverse adolescents. Objectives To investigate the prevalence of reported alcohol use, smoking and vaping, and explore whether these behaviours are associated with increased numbers of sexual partners. Design Questionnaire survey of ‘Test n Treat’ chlamydia screening trial participants. Setting and participants Sexually active students attending six London technical colleges completed confidential questionnaires and provided genitourinary samples. Results The median age of the 509 participants was 17 years (IQR: 16‐18), 47% were male, 50% were of black ethnicity, 55% reported ≥2 sexual partners in the past year (67% of males and 45% of females) and 6.2% had chlamydia infection and 0.6% gonorrhoea. Almost half (48%) reported getting drunk in the past month, 33% smoked cigarettes and 7% had ever vaped. A larger percentage of students with ≥2 sexual partners than 0‐1 partners reported getting drunk in the past month (53.7%, 144/268% versus 42.2% 94/223, adjusted prevalence ratio: 1.33, 95% confidence interval: 1.11‐1.61) and smoking cigarettes (36.6%, 100/273% versus 30.2%, 67/222, 1.34 (1.05‐1.70)). By contrast, multiple sexual partners were not associated with vaping or chlamydia infection, but numbers were small. Conclusions We found high prevalences of risky behaviour and an association between multiple sexual partners and smoking and/or getting drunk. Findings support the introduction of compulsory sex and relationship education in UK secondary schools, including information about the adverse effects of alcohol and smoking. Public contribution Participants helped with study design, conduct and interpretation.
- Published
- 2021
18. Diversity and genetic characterization of Chlamydia isolated from Siamese crocodiles (Crocodylus siamensis).
- Author
-
Chaiwattanarungruengpaisan S, Thongdee M, Arya N, Paungpin W, Sirimanapong W, and Sariya L
- Subjects
- Animals, Phylogeny, Anti-Bacterial Agents pharmacology, Thailand, Alligators and Crocodiles, Chlamydia genetics
- Abstract
Chlamydiosis, an infection caused by several Chlamydia species, has been reported in Nile, saltwater, and Siamese crocodiles. Despite its widespread reports in various countries, including Thailand, genetic information on Chlamydia species remains limited. This study presents a whole-genome-based characterization of Siamese crocodile-isolated Chlamydia. The results showed that Siamese crocodile Chlamydia contained a single circular chromosome with a size of 1.22-1.23 Mbp and a plasmid with a size of 7.7-8.0 kbp. A plasmid containing eight coding sequences (CDSs) was grouped in a β lineage. A chromosome sequence had approximately 1,018-1,031 CDSs. Chlamydial factors involving virulence were documented in terms of the presence of cytotoxins and several virulence factors in the chromosomes of Siamese crocodile Chlamydia. The analysis of antimicrobial resistance genes in the Chlamydia genome revealed that the most common resistance genes were associated with aminoglycosides, fluoroquinolones, macrolides, tetracyclines, and cephalosporins, with loose matching (identities between 21.12 % and 74.65 %). Phylogenetic analyses, encompassing the assessments of both whole proteome and nine taxonomic markers, revealed that Siamese crocodile Chlamydia was separated into three lineages (lineages I-III) with high bootstrapping statistic support. Interestingly, isolate 12-01 differed genetically from the others, suggesting that it is a new member of Chlamydia. The study findings indicate that Siamese crocodiles are susceptible hosts to Chlamydia, involving more than one species. This study is the first employing the highest number of whole-genome data on Siamese crocodile Chlamydia and provides better insights into pathogen genetics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
19. Investigation of Chlamydia pecorum in livestock from Switzerland reveals a high degree of diversity in bovine strains.
- Author
-
Hagenbuch F, Loehrer S, Marti H, Kasimov V, Jelocnik M, and Borel N
- Subjects
- Animals, Sheep, Cattle, Swine, Livestock, Switzerland epidemiology, Multilocus Sequence Typing veterinary, Phylogeny, Genetic Variation, Ruminants, Chlamydia Infections epidemiology, Chlamydia Infections veterinary, Chlamydia genetics, Cattle Diseases epidemiology, Swine Diseases
- Abstract
Chlamydia pecorum is a widespread veterinary chlamydial species causing endemic infections in livestock, such as ruminants and pigs, globally. However, there is limited contemporary knowledge on infecting strain diversity in various hosts. This study aimed to evaluate the genetic diversity of C. pecorum strains infecting Swiss livestock through C. pecorum genotyping and phylogenetic analyses in comparison to the global population, while also assessing chlamydial strains for plasmid carriage. A total of 263 C. pecorum positive samples from clinically healthy ruminant and pig herds (Bovines = 216, sheep = 25, pigs = 14) as well as placentae from eight C. pecorum positive ruminant abortion cases from other Swiss herds were investigated. The ompA and Multi-Locus sequence typing revealed novel C. pecorum genotypes, and bovine strains exhibited considerable genetic diversity, contrasting with lower diversity in sheep and pig strains. C. pecorum plasmid was detected in 100.0% of sheep (41/41) and pig (255/255) samples, and in 69.4% of bovine samples (150/216). In contrast, no plasmid was detected in the eight C. pecorum-positive ruminant abortion cases either representing plasmid-less strains or possibly escaping PCR detection due to autolysis of the placenta. This study supports the genetic diversity of C. pecorum strains, particularly in bovines, and identifies novel sequence types in Swiss livestock., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Nicole Borel reports financial support was provided by University of Zurich Vetsuisse Faculty. Nicole Borel reports a relationship with University of Zurich Vetsuisse Faculty that includes: funding grants. None If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
20. Detection of a novel genotype of Chlamydia buteonis in falcons from the Emirates.
- Author
-
Vorimore F, Aaziz R, Al Qaysi L, Wernery U, Borel N, Sachse K, and Laroucau K
- Subjects
- Humans, Animals, Multilocus Sequence Typing veterinary, Birds microbiology, Genotype, Chlamydia genetics, Chlamydiaceae, Falconiformes
- Abstract
Chlamydiaceae are a family of obligate intracellular bacterial pathogens that affect both humans and animals. Recently, a new species named Chlamydia (C.) buteonis was isolated from hawks. In this study, we aimed to investigate the prevalence of Chlamydiaceae in 60 falcons that underwent a routine health check at a specialized clinic in Dubai, United Arab Emirates. Using real-time PCR, we analyzed cloacal and tracheal swabs from these birds and found that 39 of them tested positive for Chlamydiaceae. Subsequent real-time PCR assays specific for C. psittaci, C. abortus, C. avium, and C. gallinacea yielded negative results, while testing positive for C. buteonis. Analysis of ompA and MLST sequences indicated a highly conserved group of strains within this set of samples, but with sequences distinct from the C. buteonis RSHA reference strains and other C. buteonis strains isolated from hawks in the United States. Two strains were further isolated by cell culture and sequenced using whole-genome sequencing, confirming the clustering of these falcon strains within the C. buteonis species, but in a separate clade from the previously identified hawk strains. We also developed a SNP-based PCR-HRM assay to distinguish between these different genotypes. Overall, our findings suggest a high prevalence of C. buteonis in falcons in Dubai and highlight the importance of monitoring this pathogen in birds of prey., Competing Interests: Declaration of Competing Interest None of the authors have any financial or personal relationships with any individuals or organizations that could inappropriately influence or bias this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
21. Contact tracing to control infectious disease: when enough is enough.
- Author
-
Armbruster, Benjamin and Brandeau, Margaret
- Subjects
PAPER ,METHODOLOGY ,COMMUNICABLE diseases ,SEXUALLY transmitted diseases ,HIV ,SEXUAL health ,SIMULATION methods & models ,DISEASES ,CHLAMYDIA ,DIAGNOSIS - Abstract
Contact tracing (also known as partner notification) is a primary means of controlling infectious diseases such as tuberculosis (TB), human immunodeficiency virus (HIV), and sexually transmitted diseases (STDs). However, little work has been done to determine the optimal level of investment in contact tracing. In this paper, we present a methodology for evaluating the appropriate level of investment in contact tracing. We develop and apply a simulation model of contact tracing and the spread of an infectious disease among a network of individuals in order to evaluate the cost and effectiveness of different levels of contact tracing. We show that contact tracing is likely to have diminishing returns to scale in investment: incremental investments in contact tracing yield diminishing reductions in disease prevalence. In conjunction with a cost-effectiveness threshold, we then determine the optimal amount that should be invested in contact tracing. We first assume that the only incremental disease control is contact tracing. We then extend the analysis to consider the optimal allocation of a budget between contact tracing and screening for exogenous infection, and between contact tracing and screening for endogenous infection. We discuss how a simulation model of this type, appropriately tailored, could be used as a policy tool for determining the appropriate level of investment in contact tracing for a specific disease in a specific population. We present an example application to contact tracing for chlamydia control. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
22. Review papers
- Author
-
C. D. W. König
- Subjects
Veterinary medicine ,medicine.medical_specialty ,Chlamydia ,General Veterinary ,biology ,business.industry ,Outbreak ,Antimicrobial ,biology.organism_classification ,medicine.disease ,Tissue penetration ,Dermatology ,Giemsa stain ,Mycoplasma ovipneumoniae ,Medicine ,business ,Ovis ,Keratoconjunctivitis - Abstract
The occurrence of keratoconjunctivitis infectiosa ovis (KIO) in the Netherlands was reported by Hofland et al. in 1969 for the first time. At present the disease is well known in the Netherlands. Nevertheless there are still questions about the causative agent and the most effective and easiest therapy. Most authors suppose that the disease is caused by Colesiota conjunctivae, although others mention infections by other chlamydia, Mycoplasma conjunctivae, Mycoplasma ovipneumoniae, Acholeplasma oculi and a wide variety of bacteria. The diagnosis can be made on the basis of the symptoms and the detection of the agent in conjunctival scrapings. The bacilliform bodies can be found in conjunctival smears in the cytoplasm (Giemsa, Stamp). Many therapies are used topically, parenterally or orally. Locally used eye-ointments must be effective against Colesiota; antimicrobial drugs administered by injection must be effective against the latter and also provide a sufficient cell tissue penetration with excretion into the lacrimal fluids. Injections have proved to be easier to administer, especially in serious outbreaks, but such outbreaks are exceptional (18). Some therapies have been evaluated in small scale experiments (28) as well as in field trials (17).
- Published
- 1983
23. Enhanced chlamydia surveillance in New South Wales (Australia) prisons, 2005‐2007
- Author
-
Forrest, Garry, Boonwaat, Leng, Douglas, Jenny, and Awofeso, Niyi
- Published
- 2009
- Full Text
- View/download PDF
24. Interest in Taking HIV Pre-exposure Prophylaxis Is Associated with Behavioral Risk Indicators and Self-Perceived HIV Risk Among Men Who Have Sex with Men Attending HIV Testing Venues in Sweden
- Author
-
Fredrik Månsson, Anette Agardh, Per Björkman, and Tobias Herder
- Subjects
Adult ,Male ,medicine.medical_specialty ,HIV prevention ,Human immunodeficiency virus (HIV) ,HIV Infections ,Hiv testing ,medicine.disease_cause ,Men who have sex with men ,03 medical and health sciences ,Pre-exposure prophylaxis ,0302 clinical medicine ,Arts and Humanities (miscellaneous) ,Risk Factors ,medicine ,Humans ,030212 general & internal medicine ,Homosexuality, Male ,General Psychology ,Sexual risk ,Sweden ,Original Paper ,030505 public health ,Chlamydia ,Men who have sex with men (MSM) ,Public health ,HIV ,medicine.disease ,PrEP ,Sexual orientation ,Pre-Exposure Prophylaxis ,0305 other medical science ,Psychology ,Demography - Abstract
This study explored factors associated with interest in taking PrEP among men who have sex with men (MSM) attending HIV testing venues in Sweden. Data from 658 HIV-negative respondents, surveyed by a questionnaire at six sites, were analyzed descriptively and by univariable and multivariable logistic regression. A total of 453 (68.8%) of the respondents expressed interest in taking PrEP. Reporting self-perceived risk of HIV acquisition as moderate or high, reporting ≥ 5 partners for condomless anal intercourse during the past year, and reporting hard drug use during the past year were independently associated with interest in taking PrEP. However, an aggregated variable of self-reported rectal gonorrhea, rectal chlamydia, or syphilis infection during the past year was not associated with interest in taking PrEP. Overall, Swedish MSM were well-informed regarding PrEP, and interest in taking PrEP was positively associated with sexual risk indicators.
- Published
- 2020
25. Chlamydia retesting remains low among young women in Australia: an observational study using sentinel surveillance data, 2018-2022.
- Author
-
Munari SC, Wilkinson AL, Asselin J, Owen L, Read P, Finlayson R, Martin S, Bell C, O'Connor CC, Carter A, Guy R, McNulty A, Varma R, Chow EPF, Fairley CK, Donovan B, Stoove M, Goller JL, Hocking J, and Hellard ME
- Subjects
- Humans, Female, Adolescent, Young Adult, Adult, Sentinel Surveillance, Reinfection, Australia epidemiology, Mass Screening, Chlamydia trachomatis, Chlamydia Infections diagnosis, Chlamydia Infections epidemiology, Chlamydia Infections microbiology, Chlamydia
- Abstract
Background: Chlamydia remains the most notified bacterial sexually transmissible infection in Australia with guidelines recommending testing for re-infection at 3months post treatment. This paper aimed to determine chlamydia retesting and repeat positivity rates within 2-4months among young women in Australia, and to evaluate what factors increase or decrease the likelihood of retesting., Methods: Chlamydia retesting rates among 16-29-year-old women were analysed from Australian Collaboration for Coordinated Enhanced Sentinel Surveillance of sexually transmissible infection and bloodborne virus (ACCESS) sentinel surveillance data (n =62 sites). Among women with at least one positive test between 1 January 2018 and 31 August 2022, retesting counts and proportions within 2-4months were calculated. Logistic regression was performed to assess factors associated with retesting within 2-4months., Results: Among 8758 women who were positive before 31 August 2022 to allow time for follow up, 1423 (16.2%) were retested within 2-4months, of whom 179 (12.6%) tested positive. The odds of retesting within 2-4months were 25% lower if tested in a coronavirus disease 2019 (COVID-9) pandemic year (2020-2022) (aOR=0.75; 95% CI 0.59-0.95). Among 9140 women with a positive test before 30 November 2022, 397 (4.3%) were retested too early (within 7days to 1month) and 81 (20.4%) of those were positive., Conclusions: Chlamydia retesting rates remain low with around a sixth of women retested within 2-4months in line with guidelines. Re-infection is common with around one in eight retesting positive. An increase in retesting is required to reduce the risk of reproductive complications and onward transmission.
- Published
- 2024
- Full Text
- View/download PDF
26. Chlamydia suis survival in dust: First insights.
- Author
-
Unterweger C, Koch M, Winkler S, Hammer S, Oppeneder A, and Ladinig A
- Subjects
- Swine, Animals, Dust, Chlamydia Infections veterinary, Chlamydia, Conjunctivitis microbiology, Conjunctivitis veterinary, Swine Diseases microbiology
- Abstract
Chlamydia (C.) suis, a zoonotic intracellular bacterium, is described as a causative agent for conjunctivitis, particularly in nursery and fattening pigs. Chlamydiaceae are claimed to survive drying and to persist in dust. The objective of this study was to evaluate the viability of Chlamydia in dust sampled in a fattening pig farm with a high appearance of chlamydial-induced conjunctivitis. Dust was collected and stored at room temperature. To evaluate bacterial load and survival over time, quantitative PCR (Chlamydiaceae, C. suis) and isolation in cell culture were performed every week for up to 16 weeks. While qPCR results remained highly positive with consistent bacterial loads between 10
3 and 104 copy numbers/100 μL eluate over a period of 16 weeks and even after 40 weeks, it was not possible to isolate Chlamydia except for the initial sample. These results show only short-term viability of C. suis in dust. This is an important information regarding reduction of chlamydial loads in pig farms and risk for pigs and people to get infected via dust., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
27. Role of saliva use during masturbation in the transmission of Chlamydia trachomatis in men who have sex with men
- Author
-
Eric P F Chow, Richard Gray, Christopher K. Fairley, David G. Regan, Lei Zhang, Xianglong Xu, Pingyu Zhou, and Jason J. Ong
- Subjects
Saliva ,medicine.medical_specialty ,Original Paper ,saliva ,Chlamydia ,Epidemiology ,Obstetrics ,business.industry ,Transmission (medicine) ,Anatomical ,Mutual masturbation ,transmission ,Human sexuality ,chlamydia ,medicine.disease ,medicine.disease_cause ,Confidence interval ,Men who have sex with men ,modelling ,Infectious Diseases ,medicine ,mathematical ,masturbation ,Chlamydia trachomatis ,business - Abstract
Masturbation is a common sexual practice in men, and saliva is often used as a lubricant during masturbation by men who have sex with men. However, the role of saliva use during masturbation in the transmission of chlamydia is still unclear. We developed population-level, susceptible-infected-susceptible compartmental models to explore the role of saliva use during masturbation on the transmission of chlamydia at multiple anatomical sites. In this study, we simulated both solo masturbation and mutual masturbation. Our baseline model did not include masturbation but included transmission routes (anal sex, oral-penile sex, rimming, kissing and sequential sexual practices) we have previously validated (model 1). We added masturbation to model 1 to develop the second model (model 2). We calibrated the model to five clinical datasets separately to assess the effects of masturbation on the prevalence of site-specific infection. The inclusion of masturbation (model 2) significantly worsened the ability of the models to replicate the prevalence of C. trachomatis. Using model 2 and the five data sets, we estimated that saliva use during masturbation was responsible for between 3.9% [95% confidence interval (CI) 2.0–6.8] and 6.2% (95% CI 3.8–10.5) of incident chlamydia cases at all sites. Our models suggest that saliva use during masturbation is unlikely to play a major role in chlamydia transmission between men, and even if it does have a role, about one in seven cases of urethral chlamydia might arise from masturbation.
- Published
- 2021
28. Associations Between Methods of Meeting Sexual Partners and Sexual Practices Among Heterosexuals: Cross-sectional Study in Melbourne, Australia
- Author
-
Christopher K Fairley, Kate Maddaford, Tiffany R Phillips, Eric P F Chow, Catriona S. Bradshaw, Jane S Hocking, Heidi Constantinou, and Edmond Pui Hang Choi
- Subjects
dating apps ,Cross-sectional study ,Gonorrhea ,Medicine (miscellaneous) ,Health Informatics ,Human sexuality ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,030212 general & internal medicine ,sexually transmitted infections ,Reproductive health ,Original Paper ,mobile phone ,030505 public health ,Chlamydia ,business.industry ,Odds ratio ,health risk behaviors ,medicine.disease ,Computer Science Applications ,Health promotion ,Syphilis ,internet ,0305 other medical science ,business ,Demography - Abstract
Background The association between meeting partners on the web and sexual practices has been understudied in heterosexuals. Objective This study aims to examine the associations between the methods of meeting partners and sexual practices and HIV and sexually transmitted infections (STIs) in heterosexuals. Methods We conducted a survey among heterosexuals attending the Melbourne Sexual Health Centre in 2019. This survey asked about the methods through which the participants engaged in meeting their sexual partners, sexual practices, and intravenous drug use (IVDU) over the past 3 months. The participants’ HIV and STI (chlamydia, gonorrhea, and syphilis) status was obtained from clinical testing. Multivariable logistic regression was used to examine the association between each method of meeting and the participants’ sexual practices, IVDU, and STI status. Results A total of 698 participants (325 men and 373 women) were included in the study. Most of the participants reported using only one method to meet partners (222/325, 68.3% men; 245/373, 65.7% women; P=.05). The men met partners most commonly at social venues (eg, bar, pub, or party; 126/325, 38.8%), whereas the women met partners most commonly through friends or family (178/373, 47.7%). Paying for sex was associated with men meeting partners at sex venues (adjusted odds ratio [AOR] 145.34, 95% CI 26.13-808.51) and on the internet (AOR 10.00, 95% CI 3.61-27.55). There was no association between IVDU and methods of meeting. Social venues were associated with condomless vaginal sex among men (AOR 3.31, 95% CI 1.94-5.71) and women (AOR 2.58, 95% CI 1.61-4.13) and testing positive for STI among men (AOR 3.04, 95% CI 1.24-7.48) and women (AOR 3.75, 95% CI 1.58-8.89). Conclusions Heterosexuals who met partners at social venues had a more than threefold risk of testing positive for STIs, indicating that heterosexuals may benefit from health promotion campaigns that are delivered through a public setting.
- Published
- 2021
29. [Paper microphoretic study and anatomo-pathological study of an infectious syndrome in dogs responding serologically to a strain of Rickettsia psittaci]
- Author
-
J, GROULADE, H, DRIEUX, P, GROULADE, and B, DRUFOVKA
- Subjects
Dogs ,Chlamydophila psittaci ,Animals ,Dog Diseases ,Chlamydia ,Rickettsia ,Communicable Diseases - Published
- 1954
30. Borrelia and Chlamydia can form mixed biofilms in infected human skin tissues
- Author
-
Jason P. Torres, Bernhard Zelger, K. Gupta, Gauri Gaur, Katherine R. Filush, Anthony Melillo, K. Wawrzeniak, and Eva Sapi
- Subjects
0301 basic medicine ,030106 microbiology ,lcsh:QR1-502 ,Human skin ,chlamydia ,confocal microscopy ,biofilm ,lcsh:Microbiology ,Microbiology ,03 medical and health sciences ,Lyme disease ,Borrelia ,medicine ,alginate ,Borrelia burgdorferi ,Chlamydia ,biology ,Biofilm ,medicine.disease ,biology.organism_classification ,bacterial infections and mycoses ,Borrelia lymphocytoma ,Original Research Paper ,030104 developmental biology ,Bacteria - Abstract
Our research group has recently shown that Borrelia burgdorferi, the Lyme disease bacterium, is capable of forming biofilms in Borrelia-infected human skin lesions called Borrelia lymphocytoma (BL). Biofilm structures often contain multiple organisms in a symbiotic relationship, with the goal of providing shelter from environmental stressors such as antimicrobial agents. Because multiple co-infections are common in Lyme disease, the main questions of this study were whether BL tissues contained other pathogenic species and/or whether there is any co-existence with Borrelia biofilms. Recent reports suggested Chlamydia-like organisms in ticks and Borrelia-infected human skin tissues; therefore, Chlamydia-specific polymerase chain reaction (PCR) analyses were performed in Borrelia-positive BL tissues. Analyses of the sequence of the positive PCR bands revealed that Chlamydia spp. DNAs are indeed present in these tissues, and their sequences have the best identity match to Chlamydophila pneumoniae and Chlamydia trachomatis. Fluorescent immunohistochemical and in situ hybridization methods demonstrated the presence of Chlamydia antigen and DNA in 84% of Borrelia biofilms. Confocal microscopy revealed that Chlamydia locates in the center of Borrelia biofilms, and together, they form a well-organized mixed pathogenic structure. In summary, our study is the first to show Borrelia-Chlamydia mixed biofilms in infected human skin tissues, which raises the questions of whether these human pathogens have developed a symbiotic relationship for their mutual survival.
- Published
- 2019
31. Predicting STI Diagnoses Amongst MSM and Young People Attending Sexual Health Clinics in England: Triage Algorithm Development and Validation Using Routine Clinical Data
- Author
-
Richard Gilson, Maryam Shahmanesh, Martina Furegato, Hamish Mohammed, Carina King, Gwenda Hughes, Catherine H Mercer, Andrew Copas, and John Were
- Subjects
Ethnic group ,Logistic regression ,Men who have sex with men ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Model development ,MSM ,030212 general & internal medicine ,Medical diagnosis ,Reproductive health ,lcsh:R5-920 ,030505 public health ,Chlamydia ,business.industry ,Routine data ,General Medicine ,medicine.disease ,Triage ,Predictive model ,Young people ,STI ,lcsh:Medicine (General) ,0305 other medical science ,business ,Algorithm ,Research Paper - Abstract
Background Sexual health (SH) services increasingly need to prioritise those at greatest risk of sexually transmitted infections (STIs). We used SH surveillance data to develop algorithms to triage individuals attending SH services within two high-risk populations: men who have sex with men (MSM) and young people (YP). Methods Separate multivariable logistic regression models for MSM and YP were developed using surveillance data on demographics, recent sexual history, prior STI diagnoses and drug/alcohol use from five clinics in 2015–2016 to identify factors associated with new STI diagnoses. The models were prospectively applied in one SH clinic in May 2017 as an external validation. Findings 9530 YP and 1448 MSM SH episodes informed model development. For YP, factors associated with new STI diagnosis (overall prevalence: 10.6%) were being of black or mixed white/black ethnicity; history of chlamydia diagnosis (previous year); and multiple partners/new partner (previous 3-months). The YPs model had reasonable performance (c-statistic: 0.703), but poor discrimination when externally validated (c-statistic: 0.539). For MSM, being of South Asian ethnicity; being born in Europe (excluding the UK); and condomless anal sex or drug use (both in previous 3-months) were associated with STI diagnosis (overall prevalence: 22.0%). The MSM model had a c-statistic of 0.676, reducing to 0.579 on validation. Interpretation SH surveillance data, including limited behavioural data, enabled triage algorithms to be developed, but its implementation may be problematic due to poor external performance. This approach may be more suitable to self-triage, including online, ensuring patients are directed towards appropriate services. Funding NIHR HTA programme (12/191/05)., Highlights • We report the development and validation of an algorithm predicting STI diagnosis among MSM and young people in England • Inclusion of sexual behaviour data, feasibly collected in clinical settings, was crucial to achieve reasonable model performance • External validation highlighted key limitations with automated triage based on predictive algorithms in sexual health settings
- Published
- 2018
32. The role of sexual networks in studies of how BV and STIs increase the risk of subsequent reinfection
- Author
-
Rebecca M. Brotman, Jozefien Buyze, Chris Kenyon, and Mark A. Klebanoff
- Subjects
Adult ,Sexual network ,Epidemiology ,Sexual Behavior ,urologic and male genital diseases ,medicine.disease_cause ,Logistic regression ,Risk Assessment ,Gonorrhea ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Longitudinal Studies ,030212 general & internal medicine ,Original Paper ,030505 public health ,Chlamydia ,business.industry ,Incidence ,Confounding ,Vaginosis, Bacterial ,Odds ratio ,Chlamydia Infections ,medicine.disease ,female genital diseases and pregnancy complications ,Sexual Partners ,Infectious Diseases ,Female ,Trichomonas vaginalis ,Bacterial vaginosis ,Trichomonas Vaginitis ,0305 other medical science ,Chlamydia trachomatis ,business ,Demography - Abstract
Prior studies have demonstrated that both bacterial vaginosis (BV) and sexually transmitted infections (STIs) are strong independent risk factors for subsequent STI. In observational studies of this biological enhancement (BE) hypothesis, it is important to adjust for the risk of STI exposure so that the independent effect of BE can be assessed. We sought to model if two markers of local sexual network (partner concurrency and cumulative number of STIs) represented residual confounding in the models of risk for subsequent infection in a study that screened 3620 women for STIs every 3 months for a year. Mixed-effects logistic regression was used to calculate the odds ratios for an incident diagnosis ofChlamydia trachomatis,Neisseria gonorrhoeae,Trichomonas vaginalisand BV following a diagnosis of any of these four at the prior visit, controlling for the cumulative number of STIs and partner concurrency variables. We found that partner concurrency and cumulative number of STIs were each associated with incident infection, and in general, controlling for these variables reduced the strength of the association between prior and incident infections. We conclude that the frequently found association between prior and incident STIs is associated with both BE and sexual network structure.
- Published
- 2018
33. Vaccines for Bacterial Sexually Transmitted Infections: A Realistic Goal?
- Author
-
Sparling, P. Frederick, Elkins, Christopher, Wyrick, Priscilla B., and Cohen, Myron S.
- Published
- 1994
34. Modified Public Health Automated Case Event Reporting (PACER) Platform for Enhancing Electronic Laboratory Reports with Clinical Data: Design and Implementation (Preprint)
- Author
-
Jon Duke, Andrey V Ilatovskiy, Marla Gorges, Leslie A. Lenert, Ninad K. Mishra, Myung Choi, Michael Riley, and Saugat Karki
- Subjects
medicine.medical_specialty ,EHR ,sexually transmitted diseases ,Computer science ,Interoperability ,Control (management) ,Data field ,chlamydia ,Pilot Projects ,Health Informatics ,health information interoperability ,Public health surveillance ,Server ,Epidemiology ,medicine ,Humans ,Medical diagnosis ,Original Paper ,gonorrhea ,electronic laboratory reporting ,Public health ,medicine.disease ,public health surveillance ,electronic health records ,fast healthcare interoperability resources ,Public Health ,Medical emergency ,Electronics ,electronic case reporting ,Laboratories - Abstract
Background: Public health reporting is the cornerstone of public health practices that inform prevention and control strategies. There is a need to leverage advances made in the past to implement an architecture that facilitates the timely and complete public health reporting of relevant case-related information that has previously not easily been available to the public health community. Electronic laboratory reporting (ELR) is a reliable method for reporting cases to public health authorities but contains very limited data. In an earlier pilot study, we designed the Public Health Automated Case Event Reporting (PACER) platform, which leverages existing ELR infrastructure as the trigger for creating an electronic case report. PACER is a FHIR (Fast Health Interoperability Resources)-based system that queries the electronic health record from where the laboratory test was requested to extract expanded additional information about a case. Objective: This study aims to analyze the pilot implementation of a modified PACER system for electronic case reporting and describe how this FHIR-based, open-source, and interoperable system allows health systems to conduct public health reporting while maintaining the appropriate governance of the clinical data. Methods: ELR to a simulated public health department was used as the trigger for a FHIR-based query. Predetermined queries were translated into Clinical Quality Language logics. Within the PACER environment, these Clinical Quality Language logical statements were managed and evaluated against the providers’ FHIR servers. These predetermined logics were filtered, and only data relevant to that episode of the condition were extracted and sent to simulated public health agencies as an electronic case report. Design and testing were conducted at the Georgia Tech Research Institute, and the pilot was deployed at the Medical University of South Carolina. We evaluated this architecture by examining the completeness of additional information in the electronic case report, such as patient demographics, medications, symptoms, and diagnoses. This additional information is crucial for understanding disease epidemiology, but existing electronic case reporting and ELR architectures do not report them. Therefore, we used the completeness of these data fields as the metrics for enriching electronic case reports. Results: During the 8-week study period, we identified 117 positive test results for chlamydia. PACER successfully created an electronic case report for all 117 patients. PACER extracted demographics, medications, symptoms, and diagnoses from 99.1% (116/117), 72.6% (85/117), 70.9% (83/117), and 65% (76/117) of the cases, respectively. Conclusions: PACER deployed in conjunction with electronic laboratory reports can enhance public health case reporting with additional relevant data. The architecture is modular in design, thereby allowing it to be used for any reportable condition, including evolving outbreaks. PACER allows for the creation of an enhanced and more complete case report that contains relevant case information that helps us to better understand the epidemiology of a disease. Trial Registration
- Published
- 2020
35. Chlamydia pneumonia infection and risk of multiple sclerosis: A meta-analysis.
- Author
-
Arjmandi D, Graeili Z, Mohammadi P, Arshadi M, Jafari Tadi M, Ardekani A, Naeimi R, Abbasi F, Marhoommirzabak E, Mahjour S, Sartip B, Prasa H, Fallah Omrani V, and Rostami A
- Subjects
- Humans, Prospective Studies, Multiple Sclerosis epidemiology, Multiple Sclerosis complications, Chlamydia Infections complications, Chlamydia Infections epidemiology, Pneumonia, Chlamydia
- Abstract
Background: The role of infectious agents, including Chlamydia pneumoniae (Cpn), in the development of multiple sclerosis (MS), is still a matter of major contention., Objective: This meta-analysis study aimed to assess the actual involvement of Cpn in MS development., Methods: We undertook a search of international scientific databases to identify eligible studies. We used a random-effects meta-analysis model (REM) to generate the pooled odds ratio (OR) and 95% confidence intervals (CIs). Heterogeneity was calculated using the I
2 statistic. Sensitivity and subgroup analyses were applied to assess the effects of study characteristics and socio-demographic variables on the pooled OR., Results: We identified 37 studies comprising 51 datasets that satisfied the inclusion criteria. Considering diagnostic methods for Cpn, 26 and 25 datasets used PCR- and serological-based methods, respectively. In PCR-based datasets, REM showed a significant positive association between Cpn infection and the development of MS (OR, 5.29; 95% CI, 3.12-8.97), while a non-significant positive association was achieved in serological-based datasets (OR, 1.34; 95% CI, 0.88-2.03). In subgroup analyses on PCR-based datasets, results were significant for both CSF (OR, 5.70) and serum (OR, 4.84) samples; both healthy (OR, 16.11) and hospital-based (OR, 2.88) controls; and both moderate (OR, 5.14) and high (OR, 5.48) quality studies. In serological-based datasets, only those that used CSF samples yielded significant results (OR, 3.41)., Conclusions: Our findings verify the significant positive relationship between Cpn infection and MS. We advocate prospective cohort studies with lifelong follow-ups and also experimental studies to better understand the role of Cpn in MS development., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
36. Chronic wasting associated with Chlamydia pneumoniae in three ex situ breeding facilities for tropical frogs
- Author
-
Anne Nesseler, Iris Völker, Can Imirzalioglu, Ute Kaim, Elisabeth M. Liebler-Tenorio, Nicole Schauerte, Silke Hechinger, Tobias Eisenberg, Karin Riße, Ingo Schwabe, Tobias Knauf-Witzens, Christina Geiger, Christiane Schnee, Ahmad Fawzy, and Reinhard Sting
- Subjects
medicine.medical_specialty ,Chlamydiae ,Biology ,Microbiology ,Asymptomatic ,Lethargy ,Zoonosis ,Medical microbiology ,Chlamydia pneumoniae ,medicine ,Humans ,Chlamydia ,Molecular Biology ,Wasting ,Original Paper ,Infectious disease ,General Medicine ,Chlamydia Infections ,Chlamydophila pneumoniae ,Amphibian ,medicine.disease ,biology.organism_classification ,Infectious disease (medical specialty) ,medicine.symptom ,Frog - Abstract
A number of different Chlamydia spp. have been detected in the class Amphibia with C. pneumoniae being the predominant species involved. Chlamydiae have been linked to mass mortality events, thereby representing significant pathogens that deserve attention with respect to worldwide amphibian decline. We here present six cases of chlamydiosis and asymptomatic chlamydial infections in different frog species from three ex situ amphibian conservation facilities. Clinical signs predominantly characterised by regurgitation, chronic wasting, lethargy and suspended breeding were associated with C. pneumoniae infection. Despite various treatment regimens, it was not possible to clear infections. However, intra vitam diagnostics succeeded from skin, faeces and urine for the first time.
- Published
- 2020
37. Detection of Chlamydia psittaci and Chlamydia ibidis in the Endangered Crested Ibis (Nipponia nippon)
- Author
-
Lin Liang, Zhaocai Li, Junfeng Zhang, Jia Hou, Jizhang Zhou, Yinghu Lei, Yuan Wen, Guanglan Xu, Zhongzi Lou, and Ping Liu
- Subjects
0301 basic medicine ,Genotype ,Epidemiology ,Chlamydia ibidis ,030106 microbiology ,Population ,Endangered species ,Zoology ,urologic and male genital diseases ,Birds ,Feces ,03 medical and health sciences ,Prevalence ,medicine ,Short Paper ,Animals ,Chlamydiaceae ,Crested Ibis (Nipponia nippon) ,Chlamydia ,education ,Ibis ,Chlamydia psittaci ,education.field_of_study ,biology ,Bird Diseases ,Genetic Variation ,Sequence Analysis, DNA ,Chlamydia Infections ,biology.organism_classification ,medicine.disease ,female genital diseases and pregnancy complications ,030104 developmental biology ,Infectious Diseases ,Chlamydophila psittaci ,Nipponia nippon ,Bacterial Outer Membrane Proteins - Abstract
Chlamydia spp. are a group of obligate intracellular pathogens causing a number of diseases in animals and humans. Avian chlamydiosis (AC), caused by Chlamydia psittaci (C. psittaci) as well as new emerging C. avium, C. gallinacea and C. ibidis, have been described in nearly 500 avian species worldwidely. The Crested Ibis (Nipponia nippon) is a world endangered avian species with limited population and vulnerable for various infections. To get a better understanding of the prevalence of Chlamydia spp. in the endangered Crested Ibis, faecal samples were collected and analysed. The results confirmed that 20.20% (20/99) of the faecal samples were positive for Chlamydiaceae and were identified as C. ibidis with co-existence of C. psittaci in one of the 20 positive samples. In addition, ompA sequence of C. psittaci obtained in this study was classified into the provisional genotype Matt116, while that of C. ibidis showed high genetic diversity, sharing only 77% identity with C. ibidis reference strain 10-1398/6. We report for the first time the presence of C. ibidis and C. psittaci in the Crested Ibis, which may indicate a potential threat to the endangered birds and should be aware of the future protection practice.
- Published
- 2020
38. The presence of Chlamydia trachomatis infection in men with chronic prostatitis
- Author
-
Marek Baltaziak, Bozena Zdrodowska-Stefanow, Małgorzata Skawrońska, Iwona Ostaszewska-Puchalska, Marianna Sokolowska, and Rościsław Bielecki
- Subjects
Original Paper ,medicine.medical_specialty ,Chlamydia ,business.industry ,Prostatitis ,Chlamydia trachomatis ,General Medicine ,medicine.disease ,medicine.disease_cause ,DNA extraction ,Gastroenterology ,medicine.anatomical_structure ,transrectal prostate biopsy ,Antigen ,prostatitis ,Prostate ,Internal medicine ,anti-C. trachomatis IgG antibodies ,medicine ,ligase chain reaction ,Histopathology ,anti-C. trachomatis IgA antibodies ,Ligase chain reaction ,business - Abstract
Introduction The aim of the study was to evaluate the frequency of occurrence of Chlamydia trachomatis (C.t.) DNA in the prostate material in the group of individuals with the chronic prostatitis. Material and methods The study included 65 males aged between 47 and 68 years of age, reporting for transrectal prostate biopsy because of the elevated serum prostate-specific antigen concentration and/or abnormalities detected in prostate palpation per rectum. The urethral smear collection was performed in all the patients in order to detect C.t. DNA. After that, the transrectal prostate biopsy was performed (histopathology tests, C.t. DNA). Additionally, the levels of anti-C.t. IgG antibodies and anti-C.t. IgA antibodies were checked in the serum. The DNA isolation from prostate specimens was conducted with the use of the Chelex method, while the C.t. DNA detection – with the ligase chain reaction. Specific antibodies were detected with the use of the ELISA method. Results C.t. DNA in the prostate gland was found in 7 out of 65 men (10.8%). In urethral smear, C.t. was found in none of the individuals. Anti-C.t. IgA antibodies were detected in the serum of 16/65 (24.6%), while anti-C.t. IgG antibodies in 6/65 (9.2%) of the examined males. IgA antibodies were found in two and IgG in one out of the 7 men who had C.t. infection in the prostate. Conclusions The presence of C.t. DNA in the prostate gland may be indicative of the role of chlamydia in the development of chronic prostatitis.
- Published
- 2020
39. The impact of antibiotic treatment for syphilis, chlamydia, and gonorrhoea during pregnancy on birth outcomes: A systematic review and meta-analysis.
- Author
-
Tong H, Heuer A, and Walker N
- Subjects
- Pregnancy, Female, Infant, Newborn, Humans, Stillbirth epidemiology, Anti-Bacterial Agents therapeutic use, Syphilis drug therapy, Gonorrhea drug therapy, Premature Birth epidemiology, Premature Birth prevention & control, Pregnancy Complications, Infectious drug therapy, Chlamydia
- Abstract
Background: Sexually transmissible infections are important causes of loss of health and lives in women and infants worldwide. This paper presents the methods and results of a systematic review that focuses on the impact of antibiotic treatment for syphilis, chlamydia, and gonorrhoea during pregnancy on birth outcomes for the Lives Saved Tool (LiST)., Methods: We searched PubMed, Embase, Cochrane Libraries, Global Health and Global Index Medicus for articles available until May 23rd, 2022. The search criteria focused on the impact of treatment for the three sexually transmitted infection among pregnant women. Nearly all the articles found were non-randomized studies., Results: Treatment for pregnant women with active syphilis reduced the risk of preterm birth by 52% (95% CI = 42%-61%; 11 043 participants, 15 studies; low quality); stillbirth by 79% (95% CI = 65%-88%; 14 667 participants, eight studies; low quality); and low birth weight by 50% (95% CI = 41%-58%; 9778 participants, seven studies; moderate quality). Treatment for pregnant women with chlamydia infection reduced the risk of preterm birth by 42% (95% CI = 7%-64%; 5468 participants, seven studies; low quality) and might reduce the risk of low birth weight by 40% (95% CI = 0%-64%; 4684 participants, four studies; low quality). No studies provided data on treatment of gonorrhoea therefore no meta-analysis was conducted., Conclusions: Because few studies adjusted for potential confounding factors, the overall quality of evidence was considered low. However, given the consistent and large effects, we recommend updating the estimated effect of timely detection and treatment for syphilis on preterm birth and stillbirth in the LiST model. More research is required to ascertain the effect of antibiotic treatment for chlamydia and gonorrhoea infection in pregnancy., Competing Interests: Disclosure of interest: The authors completed the ICMJE Disclosure of Interest Form (available upon request from the corresponding author) and disclose no relevant interests., (Copyright © 2023 by the Journal of Global Health. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
40. Detection of specific Chlamydia pneumoniae and cytomegalovirus antigens in human carotid atherosclerotic plaque in a Chinese population
- Author
-
Jiachao Cao, Jia Shi, Bo Dong, Suinuan Wang, Yumin Mao, and Wei Guan
- Subjects
0301 basic medicine ,immunohistochemistry detection ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Congenital cytomegalovirus infection ,Carotid endarterectomy ,030204 cardiovascular system & hematology ,specific antigen ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,Medicine ,cytomegalovirus ,Computed tomography angiography ,Chlamydia ,medicine.diagnostic_test ,business.industry ,Digital subtraction angiography ,medicine.disease ,Chlamydia pneumonia ,Pneumonia ,Stenosis ,030104 developmental biology ,Oncology ,atherosclerosis ,business ,Research Paper - Abstract
// Jiachao Cao 1 , Yumin Mao 1 , Bo Dong 1 , Wei Guan 1 , Jia Shi 1 and Suinuan Wang 1 1 Department of Neurosurgery, The Third Affiliated Hospital of Soochow University, Changzhou, China Correspondence to: Suinuan Wang, email: 292079658@qq.com Keywords: atherosclerosis, Chlamydia pneumonia, cytomegalovirus, specific antigen, immunohistochemistry detection Received: April 04, 2017 Accepted: June 04, 2017 Published: July 18, 2017 ABSTRACT To explore the relationship between certain pathogens, such as chlamydia pneumonia (Cpn) and cytomegalovirus (CMV), and carotid atherosclerosis (AS) in a Chinese population.Twenty-five carotid atherosclerotic stenosis patients from the Beijing Tiantan Hospital (affiliated with Capital Medical University) participated in the study. After undergoing digital subtraction angiography (DSA) and/or computed tomography angiography (CTA), the degree of carotid artery stenosis was over 70% in all cases, and the patients underwent carotid endarterectomy. Plaque specimens were obtained during surgery. The streptavidin-peroxidase (SP) method was used to test the Cpn and CMV antigens in the specimens, and the relationship between the Cpn and CMV pathogen infections and AS was analyzed based on the test results. In the group of 25 carotid atherosclerotic specimens, the detection rate of the Cpn-specific antigens was 84.0% (21/25). In the control group, the detection rate was 13.3% (2/15) in the ascending aortic intima. Thus, the between-group difference was significant (P
- Published
- 2017
41. Anorectal swabs as a marker of male-to-male sexual exposure in STI surveillance systems
- Author
-
Anna L Bowring, Margaret Hellard, Eric P F Chow, C van Gemert, N. Bartnik, Nicola Stephens, Christopher K Fairley, Catriona S. Bradshaw, Paul A. Agius, Megan S. C. Lim, Frances H Ampt, and C. El Hayek
- Subjects
Adult ,Male ,Sexual partner ,medicine.medical_specialty ,Sexual health clinic ,Victoria ,Epidemiology ,Sexual Behavior ,Sexually Transmitted Diseases ,medicine.disease_cause ,Men who have sex with men ,03 medical and health sciences ,0302 clinical medicine ,Acquired immunodeficiency syndrome (AIDS) ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Homosexuality, Male ,Reproductive health ,030505 public health ,Chlamydia ,business.industry ,virus diseases ,medicine.disease ,Original Papers ,Surgery ,Sexual Partners ,Infectious Diseases ,Population Surveillance ,0305 other medical science ,business ,Chlamydia trachomatis - Abstract
SUMMARYIdentification of priority populations such as men who have sex with men (MSM) is important in surveillance systems to monitor trends of sexually transmitted infections (STIs). We explored using routinely collected non-behavioural data as a means to establish MSM status in surveillance by assessing anorectal swab as a marker of male-to-male sexual exposure. We used chlamydia testing data from a sexual health clinic, 2007–2012. Men reporting any male sexual partner(s) in the previous 12 months were considered MSM. The dataset was split into development and validation samples to develop a univariate predictive model and assess the model fit. The dataset included 30 358 individual men and 48 554 episodes of STI testing; 45% were among reported MSM and an anorectal swab was performed in 40% of testing episodes. Anorectal swabbing had good diagnostic performance as a marker for MSM status (sensitivity = 87%, specificity = 99%, positive predictive value = 98·6%, negative predictive value = 90·3%). The model showed good fit against the internal validation sample (area under the curve = 0·93). Anorectal swabs are a valid marker of MSM behaviour in surveillance data from sexual health clinics, and they are likely to be particularly useful for monitoring STI trends among MSM with higher risk behaviour.
- Published
- 2017
42. Publication: a dialogue between authors and editors.
- Subjects
REPORT writing ,PUBLISHING ,CHLAMYDIA ,SEXUALLY transmitted diseases ,GREAT Britain. Committee on Publication Ethics - Abstract
The authors investigate speculations on the possible overlapping of information on chlamydia screening published in research papers entitled "Sexually Transmitted Infections" and "The Journal of Family Planning and Reproductive Health Care" in Great Britain. They presented the inquiry to the Committee on Publication Ethics (COPE). COPE explained that the event took place due to misconception among authors and editors during the publication process.
- Published
- 2009
- Full Text
- View/download PDF
43. Strategie analitiche innovative per lo sviluppo di sistemi sensoristici e metodi in spettrometria di massa
- Author
-
Manfredi, Anita
- Subjects
HPV ,Competitive immunosensors ,Paper-based assay ,CHIM/01 ,Liquid chromatography-ion-trap tandem mass spectrometry ,Immunosensor ,Quartz crystal microbalance (QCM) ,Celiotoxic cereals ,Cocktail solution ,Food safety ,Gonorrhoeae ,Celiac disease ,Rolling circle amplification ,Chlamydia ,Non compilare ,Gluten-free food ,Open-tissue transglutaminase ,Gluten - Abstract
Il lavoro presentato in questa tesi di Dottorato è incentrato sullo sviluppo di strategie analitiche innovative basate sulla sensoristica e su tecniche di spettrometria di massa in ambito biologico e della sicurezza alimentare. Il primo capitolo tratta lo studio di aspetti metodologici ed applicativi di procedure sensoristiche per l’identificazione e la determinazione di biomarkers associati alla malattia celiaca. In tale ambito, sono stati sviluppati due immunosensori, uno a trasduzione piezoelettrica e uno a trasduzione amperometrica, per la rivelazione di anticorpi anti-transglutaminasi tissutale associati a questa malattia. L’innovazione di questi dispositivi riguarda l’immobilizzazione dell’enzima tTG nella conformazione aperta (Open-tTG), che è stato dimostrato essere quella principalmente coinvolta nella patogenesi. Sulla base dei risultati ottenuti, entrambi i sistemi sviluppati si sono dimostrati una valida alternativa ai test di screening attualmente in uso per la diagnosi della celiachia. Rimanendo sempre nel contesto della malattia celiaca, ulteriore ricerca oggetto di questa tesi di Dottorato, ha riguardato lo sviluppo di metodi affidabili per il controllo di prodotti “gluten-free”. Il secondo capitolo tratta lo sviluppo di un metodo di spettrometria di massa e di un immunosensore competitivo per la rivelazione di prolammine in alimenti “gluten-free”. E’ stato sviluppato un metodo LC-ESI-MS/MS basato su un’analisi target con modalità di acquisizione del segnale selected reaction monitoring per l’identificazione di glutine in diversi cereali potenzialmente tossici per i celiaci. Inoltre ci si è focalizzati su un immunosensore competitivo per la rivelazione di gliadina, come metodo di screening rapido di farine. Entrambi i sistemi sono stati ottimizzati impiegando miscele di farina di riso addizionata di gliadina, avenine, ordeine e secaline nel caso del sistema LC-MS/MS e con sola gliadina nel caso del sensore. Infine i sistemi analitici sono stati validati analizzando sia materie prime (farine) che alimenti (biscotti, pasta, pane, etc.). L’approccio sviluppato in spettrometria di massa apre la strada alla possibilità di sviluppare un test di screening multiplo per la valutazione della sicurezza di prodotti dichiarati “gluten-free”, mentre ulteriori studi dovranno essere svolti per ricercare condizioni di estrazione compatibili con l’immunosaggio competitivo, per ora applicabile solo all’analisi di farine estratte con etanolo. Terzo capitolo di questa tesi riguarda lo sviluppo di nuovi metodi per la rivelazione di HPV, Chlamydia e Gonorrhoeae in fluidi biologici. Si è scelto un substrato costituito da strips di carta in quanto possono costituire una valida piattaforma di rivelazione, offrendo vantaggi grazie al basso costo, alla possibilità di generare dispositivi portatili e di poter visualizzare il risultato visivamente senza la necessità di strumentazioni. La metodologia sviluppata è molto semplice, non prevede l’uso di strumentazione complessa e si basa sull’uso della isothermal rolling-circle amplification per l’amplificazione del target. Inoltre, di fondamentale importanza, è l’utilizzo di nanoparticelle colorate che, essendo state funzionalizzate con una sequenza di DNA complementare al target amplificato derivante dalla RCA, ne permettono la rivelazione a occhio nudo mediante l’uso di filtri di carta. Queste strips sono state testate su campioni reali permettendo una discriminazione tra campioni positivi e negativi in tempi rapidi (10-15 minuti), aprendo una nuova via verso nuovi test altamente competitivi con quelli attualmente sul mercato. The work presented in this PhD thesis is focused on the development of innovative analytical strategies based on sensor technology and mass spectrometry techniques in biological field and food safety. The first chapter deals on the study of methodological aspects and applications of sensing procedures for the identification and determination of biomarkers associated with celiac disease. In this context, a piezoelectric and amperometric immunosersor have been developed for the detection of anti-tissue transglutaminase antibodies associated with this disease. The innovation of these devices concerns the immobilization of the enzyme tTG in its open conformation (Open-tTG), which has been shown to be the one mainly involved in the pathogenesis. On the basis of the results, both systems are a good alternative to the screening tests currently in use for the diagnosis of celiac disease. In the context of the research theme aimed at developing new methods for the diagnosis of celiac disease, a further research objective of PhD thesis was the development of reliable methods for the control of gluten-free products. For this purpose, the second chapter deals on the development of mass spectrometry-based methods and of a competitive immunosensor for the detection of prolamines in gluten-free foods. A targeted proteomic LC-ESI-MS/MS-based method for simultaneous determination of gluten from different celiotoxic cereals on foods, was developed. In addition, the attention was focused on a competitive immunosensor as a screening rapid method for the detection of gliadin in flours. Both systems have been optimized using mixtures of rice flour fortified with gliadins, avenins, hordeins and secalins in case of LC-MS/MS analysis and just with gliadins in case of the sensor. Finally, these systems have been validated by analyzing both raw materials (flours) and food samples (biscuits, pasta, bread, etc.). The mass spectrometry approach opens the way to the possibility to perform a MS-based multiplex screening for the assessment of gluten-free products safety, but further studies should be conducted to investigate extraction conditions compatible with the competitive immunoassay that so far can just be used for the analysis of flours extracted with ethanol. The third chapter of this thesis concerns the development of new methods for the detection of HPV, Chlamydia and Gonorrhoeae in biological fluids. It has been chosen a strip of paper as a substrate which can constitute a valid detection platform, offering advantages due to the low cost, the ability to generate mobile devices and allows the visualization of results without instrumentations. The developed methodology is very simple, does not require the use of complex instrumentation and is based on the use of isothermal rolling circle amplification to amplify the target. Furthermore, of fundamental importance, is the use of nanoparticles with intrinsic coloration functionalized with a DNA sequence complementary to the amplified target deriving from RCA, because they allow the visualization by naked eye through the use of paper filters. These strips were tested on real samples allowing discrimination between positive and negative samples in a short time (10-15 minutes), opening the way to new and highly competitive assays with those currently available.
- Published
- 2016
44. Nowcasting Sexually Transmitted Infections in Chicago: Predictive Modeling and Evaluation Study Using Google Trends
- Author
-
Runa Bhaumik, Amy K. Johnson, Supriya D. Mehta, and Irina Tabidze
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,020205 medical informatics ,Gonorrhea ,Sexually Transmitted Diseases ,Psychological intervention ,Google Trends ,Health Informatics ,02 engineering and technology ,urologic and male genital diseases ,infodemiology ,Infodemiology ,infoveillance ,03 medical and health sciences ,0302 clinical medicine ,Prevalence ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Humans ,Syphilis ,030212 general & internal medicine ,sexually transmitted infections ,Chicago ,Original Paper ,Chlamydia ,business.industry ,Public health ,Public Health, Environmental and Occupational Health ,Regression analysis ,Chlamydia Infections ,medicine.disease ,health information technology ,Data quality ,Infoveillance ,surveillance ,Female ,Public Health ,Public aspects of medicine ,RA1-1270 ,business ,Social Media ,Forecasting ,Demography - Abstract
Background Sexually transmitted infections (STIs) pose a significant public health challenge in the United States. Traditional surveillance systems are adversely affected by data quality issues, underreporting of cases, and reporting delays, resulting in missed prevention opportunities to respond to trends in disease prevalence. Search engine data can potentially facilitate an efficient and economical enhancement to surveillance reporting systems established for STIs. Objective We aimed to develop and train a predictive model using reported STI case data from Chicago, Illinois, and to investigate the model’s predictive capacity, timeliness, and ability to target interventions to subpopulations using Google Trends data. Methods Deidentified STI case data for chlamydia, gonorrhea, and primary and secondary syphilis from 2011-2017 were obtained from the Chicago Department of Public Health. The data set included race/ethnicity, age, and birth sex. Google Correlate was used to identify the top 100 correlated search terms with “STD symptoms,” and an autocrawler was established using Google Health Application Programming Interface to collect the search volume for each term. Elastic net regression was used to evaluate prediction accuracy, and cross-correlation analysis was used to identify timeliness of prediction. Subgroup elastic net regression analysis was performed for race, sex, and age. Results For gonorrhea and chlamydia, actual and predicted STI values correlated moderately in 2011 (chlamydia: r=0.65; gonorrhea: r=0.72) but correlated highly (chlamydia: r=0.90; gonorrhea: r=0.94) from 2012 to 2017. However, for primary and secondary syphilis, the high correlation was observed only for 2012 (r=0.79), 2013 (r=0.77), 2016 (0.80), and 2017 (r=0.84), with 2011, 2014, and 2015 showing moderate correlations (r=0.55-0.70). Model performance was the most accurate (highest correlation and lowest mean absolute error) for gonorrhea. Subgroup analyses improved model fit across disease and year. Regression models using search terms selected from the cross-correlation analysis improved the prediction accuracy and timeliness across diseases and years. Conclusions Integrating nowcasting with Google Trends in surveillance activities can potentially enhance the prediction and timeliness of outbreak detection and response as well as target interventions to subpopulations. Future studies should prospectively examine the utility of Google Trends applied to STI surveillance and response.
- Published
- 2020
45. Higher organism load associated with failure of azithromycin to treat rectal chlamydia
- Author
-
Jane S Hocking, Lenka A. Vodstrcil, Marcus Y Chen, Fabian Y S Kong, Sepehr N. Tabrizi, Christopher K Fairley, Samuel Phillips, Matthew Law, Catriona S. Bradshaw, and Glenda Fehler
- Subjects
Adult ,Male ,Risk ,0301 basic medicine ,medicine.medical_specialty ,Adolescent ,Victoria ,Epidemiology ,030106 microbiology ,Chlamydia trachomatis ,Azithromycin ,medicine.disease_cause ,Asymptomatic ,Men who have sex with men ,Sexual and Gender Minorities ,Young Adult ,03 medical and health sciences ,Internal medicine ,medicine ,Humans ,Proctitis ,Aged ,Retrospective Studies ,Chlamydia ,business.industry ,Lymphogranuloma venereum ,Rectum ,Odds ratio ,Chlamydia Infections ,Middle Aged ,medicine.disease ,Original Papers ,Bacterial Load ,Anti-Bacterial Agents ,Rectal Diseases ,Infectious Diseases ,Immunology ,medicine.symptom ,business ,medicine.drug - Abstract
SUMMARYRepeat rectal chlamydia infection is common in men who have sex with men (MSM) following treatment with 1 g azithromycin. This study describes the association between organism load and repeat rectal chlamydia infection, genovar distribution, and efficacy of azithromycin in asymptomatic MSM. Stored rectal chlamydia-positive samples from MSM were analysed for organism load and genotyped to assist differentiation between reinfection and treatment failure. Included men had follow-up tests within 100 days of index infection. Lymphogranuloma venereum and proctitis diagnosed symptomatically were excluded. Factors associated with repeat infection, treatment failure and reinfection were investigated. In total, 227 MSM were included – 64 with repeat infections [28·2%, 95% confidence interval (CI) 22·4–34·5]. Repeat positivity was associated with increased pre-treatment organism load [odds ratio (OR) 1·7, 95% CI 1·4–2·2]. Of 64 repeat infections, 29 (12·8%, 95% CI 8·7–17·8) were treatment failures and 35 (15·4%, 95% CI 11·0–20·8) were reinfections, 11 (17·2%, 95% CI 8·9–28·7) of which were definite reinfections. Treatment failure and reinfection were both associated with increased load (OR 2·0, 95% CI 1·4–2·7 and 1·6, 95% CI 1·2–2·2, respectively). The most prevalent genovars were G, D and J. Treatment efficacy for 1 g azithromycin was 83·6% (95% CI 77·2–88·8). Repeat positivity was associated with high pre-treatment organism load. Randomized controlled trials are urgently needed to evaluate azithromycin's efficacy and whether extended doses can overcome rectal infections with high organism load.
- Published
- 2016
46. Chlamydia prevalence in Polish pig herds
- Author
-
Aleksandra Kumala, Krzysztof Rypuła, Paweł Chorbiński, Krzysztof Dudek, Katarzyna Płoneczka-Janeczko, and Ewa Karuga-Kuźniewska
- Subjects
0301 basic medicine ,Veterinary medicine ,Swine ,040301 veterinary sciences ,Epidemiology ,Chlamydiae ,urologic and male genital diseases ,Serology ,0403 veterinary science ,03 medical and health sciences ,Chlamydia PCR ,Prevalence ,medicine ,Animals ,Chlamydia ,Economic consequences ,Subclinical infection ,Swine Diseases ,biology ,04 agricultural and veterinary sciences ,Chlamydia Infections ,biology.organism_classification ,Serum samples ,medicine.disease ,Original Papers ,female genital diseases and pregnancy complications ,030104 developmental biology ,Infectious Diseases ,Herd ,Female ,Poland - Abstract
SUMMARYChlamydiae are frequently encountered intracellular Gram-negative bacteria. In pigs, these bacteria in combination with other pathogens contribute to the induction of a multi-aetiological syndrome. One of the major characteristics of Chlamydia spp. is their ability to cause prolonged, often subclinical infections. While the economic consequences of Chlamydia spp. infections in pig farms are not fully established, we know that reproductive disorders and other syndromes correlated with Chlamydia infection can lead to financial loss as a result of a reduction in pork production. Additionally, Chlamydia spp. presents a potential zoonotic hazard, therefore determining the prevalence of Chlamydia in pig populations is critical. In the present study 97 pig herds from Poland were involved. To determine the prevalence of Chlamydia PCR and CFT tests were used. In total 797 vaginal samples, 797 conjunctival samples, and 235 serum samples were collected and tested. The study took place from 2011 to 2014. We found Chlamydia spp. present in 71·2% of all tested farms. The percentage of animals testing positive on any given farm varied from 20% to 100%.
- Published
- 2016
47. Tempest in a teapot: A systematic review of HPV vaccination and risk compensation research
- Author
-
Jessica A. Kahn, Monica L. Kasting, Gilla K. Shapiro, Zeev Rosberger, and Gregory D. Zimet
- Subjects
Male ,medicine.medical_specialty ,pediatrics ,Sexual Behavior ,infectious disease ,Immunology ,Population ,Sexually Transmitted Diseases ,Poison control ,CINAHL ,risk compensation ,law.invention ,03 medical and health sciences ,Risk-Taking ,0302 clinical medicine ,Condom ,law ,030225 pediatrics ,Injury prevention ,medicine ,Humans ,Immunology and Allergy ,Papillomavirus Vaccines ,030212 general & internal medicine ,education ,Pharmacology ,education.field_of_study ,HPV vaccination ,Chlamydia ,behavior ,business.industry ,Incidence ,Vaccination ,medicine.disease ,3. Good health ,Surgery ,Sexual intercourse ,adolescent ,Female ,sexual disinhibition ,business ,Research Paper ,Demography - Abstract
There has been some concern among parents and in the media that vaccinating children against human papillomavirus could be seen as giving children permission to engage in risky sexual behaviors (also known as sexual disinhibition). Several studies have found this concern to be unfounded but there have been no attempts to synthesize the relevant studies in order to assess if there is evidence of sexual disinhibition. The aim of this study was to synthesize recent literature examining sexual behaviors and biological outcomes (e.g., sexually transmitted infections) post-HPV vaccination. We reviewed literature from January 1, 2008-June 30, 2015 using PubMed, CINAHL, and Embase with the following search terms: [(sex behavior OR sex behavior OR sexual) AND (human papillomavirus OR HPV) AND (vaccines OR vaccine OR vaccination)] followed by a cited reference search. We included studies that examined biological outcomes and reported behaviors post-vaccination in both males and females. Studies were reviewed by title and abstract and relevant studies were examined as full-text articles. We identified 2,503 articles and 20 were eventually included in the review. None of the studies of sexual behaviors and/or biological outcomes found evidence of riskier behaviors or higher rates of STIs after HPV vaccination. Instead, the studies found that vaccinated compared to unvaccinated individuals were less likely to report vaginal intercourse without a condom (OR = 0.5; 95%CI = 0.4–0.6) and non-use of contraception (OR = 0.27; 95%CI = 0.15–0.48) and unvaccinated participants had higher rates of Chlamydia (OR = 2.3; 95%CI = 1.06–5.00). These results should be reassuring to parents and health care providers.
- Published
- 2016
48. Cytokine profile in Nigerians with tubal infertility
- Author
-
Li Bin, Anthony A. Oni, M A Charles-Davies, VO Taiwo, Augusta Chinyere Nsonwu-Anyanwu, and Folashade Adenike Bello
- Subjects
0301 basic medicine ,Vaginal discharge ,Infertility ,medicine.medical_specialty ,Immunology ,Chlamydia trachomatis ,medicine.disease_cause ,law.invention ,03 medical and health sciences ,law ,medicine ,Immunology and Allergy ,Sex organ ,Gynecology ,Original Paper ,Chlamydia ,biology ,business.industry ,Nigerians ,medicine.disease ,cytokines ,030104 developmental biology ,Gram staining ,biology.protein ,tubal obstruction ,Antibody ,medicine.symptom ,business ,infertility - Abstract
INTRODUCTION Immune response to genital Chlamydia trachomatis infection is involved in both immunity and pathology. The cytokine profile during infection has been implicated in the disease outcome, either resolution or severe sequelae. Serum cytokines of Chlamydia positive Nigerian women with tubal infertility were assessed to determine their possible relationship with tubal occlusion. MATERIAL AND METHODS One hundred and fifty age-matched consenting women (100 fertile and 50 with tubal infertility) were recruited based on C. trachomatis antibody positivity and grouped into infertile Chlamydia positive (CTpos) women (n = 50), fertile Chlamydia positive women (n = 50) and fertile Chlamydia negative (CTneg) women as controls (n = 50). High vaginal swabs and endo-cervical swabs were collected for microscopy, culture and gram staining. Cytokines [transforming growth factor β1 (TGF-β1), interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), interleukin (IL)-4, IL-10 and IL-17A] were estimated by ELISA in sera. Data were analyzed using ANOVA, χ (2) and Spearman's correlation at p = 0.05. RESULTS Lower IFN-γ levels were observed in infertile women compared to fertile women. Fertile CTneg women had significantly higher TNF-α, and TGF-β1 compared to fertile and infertile CTpos women, respectively. Lower IL-10 levels were seen in fertile CTpos women compared to the infertile CTpos group. Vaginal discharge was negatively correlated with TNF-α and IFN-γ and positively with IL-4 in Chlamydia positive women. CONCLUSIONS Chlamydia positive women with tubal infertility have higher IL-10 and lower IFN-γ levels than controls, which may contribute to their development of tubal pathology.
- Published
- 2016
49. Physcion, a novel anthraquinone derivative against Chlamydia psittaci infection.
- Author
-
Liu X, Hu H, Liu J, Chen J, Chu J, and Cheng H
- Subjects
- Humans, Animals, Anthraquinones, Doxycycline, Chickens, Chlamydophila psittaci physiology, Psittacosis microbiology, Psittacosis veterinary, Chlamydia
- Abstract
Physcion, a natural anthraquinone derivative, has been reported to exert remarkable antibacterial activities against Staphylococcus aureus,Staphylococcus epidermidis and Pseudomonas aeruginosa. However, it is not fully illustrated as anti-Chlamydia substance. In the present study, minimum inhibitory concentration(MIC)values for physcion against Chlamydia psittaci(C.psittaci) 6BC, C.psittaci SBL and C.psittaci HJ were 128 μg/mL,256 μg/mL and 128 μg/mL while minimum bactericidal concentration (MBC) values were 256 μg/mL,512 μg/mL and 256 μg/mL,respectively. Moreover, Chlamydial adhesion to Hela 229 cells was blocked in a dose-dependent manner and RB-to-EB differentiation was inhibited by physcion from 28 to 48 hpi.Post treatment,upregulation of LC3-II was in a dose-dependent manner, indicating physcion activated autophagy and bacterial clearance.To validate clinical efficacy,49 SPF chickens aged 21days were divided into 5 groups and infected intra-laryngeally with 0.2 mL of 1 × 10
7 IFU/mL C.psittaci 6 BCE.Three days later, birds received orally with serial doses of physcion (4 mg/kg to 9 mg/kg), or 3 mg/kg of doxycycline for 6 days.Chickens with difficulty in breathing were alleviated significantly with increasing concentrations of physicon.Postmortem,lesions of air sacs were reduced significantly in a dose-dependent manner.More importantly,birds with 9 mg/kg of physcion could alleviate lesions of air sacs and lungs, and reduce bacterial loads in spleens, which was comparable to doxycycline treatment. Based on above evidences, physcion is a promising cost-effective natural drug by blocking Chlamydial adhesions to host cells, RB-to-EB differentiation and activating bacterial autophagy and it will be a good alternative to doxycycline combating virulent C.psittaci infection, contributing to eradication of Chlamydial transmission from animals to human beings., Competing Interests: Declaration of Competing Interest We declare that we have no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
50. Hepatitis B virus core antigen as a carrier for Chlamydia trachomatis MOMP multi-epitope peptide enhances protection against genital chlamydial infection
- Author
-
Juan Feng, Shao Chen, Shanli Zhu, Xiangyang Xue, Lifang Zhang, Wangqi Du, Yan Lv, Yirong Xiong, and Pengfei Jiang
- Subjects
multi-epitope peptide ,HBcAg ,Blotting, Western ,chlamydia trachomatis ,Biology ,medicine.disease_cause ,Polymerase Chain Reaction ,Epitope ,Epitopes ,Mice ,Antigen ,Immunity ,vaccine ,medicine ,Animals ,Vaccines, Virus-Like Particle ,Immune response ,Chlamydia ,Immunogenicity ,Research Paper: Immunology ,major outer membrane protein ,Chlamydia Infections ,medicine.disease ,Antibodies, Bacterial ,Hepatitis B Core Antigens ,Virology ,Bacterial vaccine ,Disease Models, Animal ,Oncology ,Bacterial Vaccines ,Immunology ,Immunology and Microbiology Section ,Chlamydia trachomatis ,Bacterial Outer Membrane Proteins ,Plasmids - Abstract
Chlamydia trachomatis (Ct) is the leading cause of sexually transmitted diseases worldwide. There is no safe and effective vaccine to control the spread of Ct. In development of Ct vaccine, selection of appropriate candidate antigens and an effective delivery system may be the main challenges. Multi-epitope of major outer membrane protein (MOMPm) is the most suitable candidate for a Ct vaccine, while hepatitis B virus core antigen (HBcAg) has unique advantages as vaccine delivery system. Therefore, in this study, we evaluated the immunogenicity and protective immune response of a novel candidate vaccine in a murine model of chlamydial genital infection. This candidate vaccine comprises MOMPm peptide delivered with HBcAg. Our results of Ct-specific serum IgG and secretory IgA assay, cytokine assay, and cytotoxic T-lymphocyte assay revealed that immunogenicity of the candidate vaccine was much better than that of the corresponding synthetic MOMPm peptide. Furthermore, the protective effect of the candidate vaccine was also shown much better than that of the synthetic peptide by calculating the isolation of Chlamydia from vaginal swabs and histopathological analysis. Taken together, our results indicate that HBcAg carrying Ct MOMPm could be an effective immune prophylactic for chlamydial infection.
- Published
- 2015
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.