48 results on '"Ramírez AL"'
Search Results
2. Challenging Assumptions about the Achievement Gap: Part Two: The Matter of Dropouts
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Ramirez, Al and Carpenter, Dick
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- 2009
3. Challenging Assumptions about the Achievement Gap
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Ramirez, Al and Carpenter, Dick
- Published
- 2005
4. Assessment-Driven Reform: The Emperor Still Has No Clothes
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Ramirez, Al
- Published
- 1999
5. Primes in numerical semigroups
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Ramírez Alfonsín, J.L. and Skałba, M.
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Mathematics ,QA1-939 - Abstract
Let $0 be two relatively prime integers and let $\langle a,b\rangle $ be the numerical semigroup generated by $a$ and $b$ with Frobenius number $g(a,b)=ab-a-b$. In this note, we prove that there exists a prime number $p\in \langle a,b\rangle $ with $p when the product $ab$ is sufficiently large. Two related conjectures are posed and discussed as well.
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- 2021
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6. Cardioprotection with halogenated gases: how does it occur?
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Guerrero-Orriach JL, Escalona Belmonte JJ, Ramirez Fernandez A, Ramirez Aliaga M, Rubio Navarro M, and Cruz Mañas J
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Sevoflurane ,Preconditioning ,Postconditioning ,Mechanisms ,Enzyme ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Jose Luis Guerrero-Orriach,1–3 Juan Jose Escalona Belmonte,1 Alicia Ramirez Fernandez,1 Marta Ramirez Aliaga,1 Manuel Rubio Navarro,1 Jose Cruz Mañas1 1Department of Cardioanesthesiology, Virgen de la Victoria University Hospital, 2Instituto de Investigación Biomédica de Málaga (IBIMA), 3Department of Pharmacology and Pediatrics, University of Malaga, Malaga, Spain Abstract: Numerous studies have studied the effect of halogenated agents on the myocardium, highlighting the beneficial cardiac effect of the pharmacological mechanism (preconditioning and postconditioning) when employed before and after ischemia in patients with ischemic heart disease. Anesthetic preconditioning is related to the dose-dependent signal, while the degree of protection is related to the concentration of the administered drug and the duration of the administration itself. Triggers for postconditioning and preconditioning might have numerous pathways in common; mitochondrial protection and a decrease in inflammatory mediators could be the major biochemical elements. Several pathways have been identified, including attenuation of NFκB activation and reduced expression of TNFα, IL-1, intracellular adhesion molecules, eNOS, the hypercontraction reduction that follows reperfusion, and antiapoptotic activating kinases (Akt, ERK1/2). It appears that the preconditioning and postconditioning triggers have numerous similar paths. The key biochemical elements are protection of the mitochondria and reduction in inflammatory mediators, both of which are developed in various ways. We have studied this issue, and have published several articles on cardioprotection with halogenated gases. Our results confirm greater cardioprotection through myocardial preconditioning in patients anesthetized with sevoflurane compared with propofol, with decreasing levels of troponin and N-terminal brain natriuretic peptide prohormone. The difference between our studies and previous studies lies in the use of sedation with sevoflurane in the postoperative period. The results could be related to a prolonged effect, in addition to preconditioning and postconditioning, which could enhance the cardioprotective effect of sevoflurane in the postoperative period. With this review, we aim to clarify the importance of various mechanisms involved in preconditioning and postconditioning with halogenated gases, as supported by our studies. Keywords: sevoflurane, preconditioning, postconditioning, mechanisms, enzyme
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- 2017
7. Application for computational cluster performance tests configured in HTCONDOR
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Orejuela Vivian, Ramirez Álvaro Sánchez, Toro Andrés Felipe, Gonzalez Andrés Felipe, and Briñez Diego
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Computational hight performance ,Cluster ,HTCondor ,Programing Pararell ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Increase the processing power in less time with high performance low-cost process is important for universities, for this reason computational clusters take paramount importance nowadays. In this paper it is shown the study of the performance time of a group that has been physically configured with a node and 3 nodes with the Core 2 Duo Quad processors, which have a Scientific Linux operating system and a cluster management software called HTCONDOR which is described time in the C language, to obtain the prime numbers in a range of 1 to 15 million and thus be able to launch the process from the point of destination to the worker nodes divided by groups of 5 million and take the measure of time. Achieving the difference between runtime on a PC and a high-performance cluster.
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- 2018
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8. Defective pro-IL-1β responses in macrophages from aged mice
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Ramirez Alejandro, Rathinam Vijay, Fitzgerald Katherine A, Golenbock Douglas T, and Mathew Anuja
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Ageing ,Macrophages ,Aged mice ,NLRP3 ,Inflammasome ,IL-1β ,Immunologic diseases. Allergy ,RC581-607 ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background Cytokines regulated by the inflammasome pathway have been extensively implicated in various age-related immune pathologies. We set out to elucidate the contribution of the nod-like receptor protein 3 (NLRP3) inflammasome pathway to the previously described deficiencies in IL-1β production by macrophages from aged mice. We examined the production of pro-IL-1β and its conversion into IL-1β as two separate steps and compared these cytokine responses in bone marrow derived macrophages from young (6–8 weeks) and aged (18–24 months) C57BL/6 mice. Findings Relative to macrophages from young mice, macrophages from aged mice produced less pro-IL-1β after TLR4 stimulation with LPS. However upon activation of the NLRP3 inflammasome with ATP, macrophages from young and aged mice were able to efficiently convert and secrete intracellular pro-cytokines as functional cytokines. Conclusions Lower levels of IL-1β production are a result of slower and lower overall production of pro-IL-1β in macrophages from aged mice.
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- 2012
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9. Association of intradialytic hypotension and convective volume in hemodiafiltration: results from a retrospective cohort study
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Mora-Bravo Franklin G, De-La-Cruz Guadalupe, Rivera Sonia, Ramírez Alfonso, Raimann Jochen G, and Pérez-Grovas Héctor
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Intradialytic hypotension ,Hemodiafiltration ,Convective volume ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Abstract Background Hemodiafiltration (HDF), as a convective blood purification technique, has been associated with favorable outcomes improved phosphate control, removal of middle-molecules such as Beta2-microglobulin and the occurrence of intradialytic hypotension (IDH) as compared to diffusive techniques. The aim of this retrospective cohort study in dialysis patients receiving HDF in one urban dialysis facility in Mexico City was to investigate the occurrence of IDH during HDF treatments with varying convective volume prescriptions. Methods Subjects were stratified into equal groups of percentiles of convective volume prescription: Group 1 of 0 to 7.53 liters, group 2 of 7.54 to 14.8 liters, group 3 of 14.9 to 16.96 liters, group 4 of 16.97 to 18.9 liters, group 5 of 21 to 19.9 liters and group 6 of 21.1 to 30 liters. Logistic Regression with and without adjustment for confounding factors was used to evaluate factors associated with the occurrence of IDH. Results 2276 treatments of 154 patients were analyzed. IDH occurred during 239 HDF treatments (10.5% of all treatments). Group 1 showed 31 treatments (8.2%) with IDH whereas group 6 showed IDH in only 15 sessions (4% of all treatments). Odds Ratio of IDH for Group 6 was 0.47 (95% CI 0.25 to 0.88) as compared to Group 1 after adjustment. Conclusions In summary the data of this retrospective cohort study shows an inverse correlation between the occurrence of IDH and convective volume prescription. Further research in prospective settings is needed to confirm these findings.
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- 2012
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10. Evolution of Dengue Virus Type 3 Genotype III in Venezuela: Diversification, Rates and Population Dynamics
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Moratorio Gonzalo, Hernández Rosa, Zambrano Julio, Alarcón Victor, Comach Guillermo, Camacho Daria, Caraballo Gerson, Gerder Marlene, Moros Zoila, Fajardo Alvaro, Ramírez Alvaro, Cristina Juan, and Liprandi Ferdinando
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Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Dengue virus (DENV) is a member of the genus Flavivirus of the family Flaviviridae. DENV are comprised of four distinct serotypes (DENV-1 through DENV-4) and each serotype can be divided in different genotypes. Currently, there is a dramatic emergence of DENV-3 genotype III in Latin America. Nevertheless, we still have an incomplete understanding of the evolutionary forces underlying the evolution of this genotype in this region of the world. In order to gain insight into the degree of genetic variability, rates and patterns of evolution of this genotype in Venezuela and the South American region, phylogenetic analysis, based on a large number (n = 119) of envelope gene sequences from DENV-3 genotype III strains isolated in Venezuela from 2001 to 2008, were performed. Results Phylogenetic analysis revealed an in situ evolution of DENV-3 genotype III following its introduction in the Latin American region, where three different genetic clusters (A to C) can be observed among the DENV-3 genotype III strains circulating in this region. Bayesian coalescent inference analyses revealed an evolutionary rate of 8.48 × 10-4 substitutions/site/year (s/s/y) for strains of cluster A, composed entirely of strains isolated in Venezuela. Amino acid substitution at position 329 of domain III of the E protein (A→V) was found in almost all E proteins from Cluster A strains. Conclusions A significant evolutionary change between DENV-3 genotype III strains that circulated in the initial years of the introduction in the continent and strains isolated in the Latin American region in recent years was observed. The presence of DENV-3 genotype III strains belonging to different clusters was observed in Venezuela, revealing several introduction events into this country. The evolutionary rate found for Cluster A strains circulating in Venezuela is similar to the others previously established for this genotype in other regions of the world. This suggests a lack of correlation among DENV genotype III substitution rate and ecological pattern of virus spread.
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- 2010
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11. La erección de nuevas sedes episcopales en el reinado de Felipe II: el caso de la ciudad de Xàtiva (Reino de Valencia)
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Ramírez Aledón, Germán
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History of Spain ,DP1-402 ,Modern history, 1453- ,D204-475 - Abstract
En el Reino de Valencia la división episcopal viene determinada por la disputa de su territorio entre las Coronas de Castilla y de Aragón en el proceso de conquista cristiana. La reivindicación de la sede episcopal de la ciudad de Saetabis (Xàtiva), de origen visigodo, pronto fue anulada por la presión de Orihuela, desgajada de la diócesis de Cartagena en 1564. Xátiva, por contra, fracasará en su intento. En estos conflictos el rey mantuvo una actitud que podemos calificar de «neutral», aunque influido por el problema morisco y la deficiente atención pastoral de sus subditos.
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- 1999
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12. Microbial community dynamics in blood, faeces and oral secretions of neotropical bats in Casanare, Colombia.
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Luna N, Páez-Triana L, Ramírez AL, Muñoz M, Goméz M, Medina JE, Urbano P, Barragán K, Ariza C, Martínez D, Hernández C, Patiño LH, and Ramirez JD
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- Animals, Colombia epidemiology, Microbiota genetics, Bacteria genetics, Bacteria classification, Bacteria isolation & purification, High-Throughput Nucleotide Sequencing, Fungi genetics, Fungi isolation & purification, Fungi classification, Metagenomics methods, Mouth microbiology, Mouth virology, RNA, Ribosomal, 16S genetics, Viruses genetics, Viruses isolation & purification, Viruses classification, Saliva microbiology, Saliva virology, Chiroptera microbiology, Chiroptera virology, Feces microbiology, Feces virology
- Abstract
Bats are known reservoirs for a wide range of pathogenic microorganisms, including viruses, bacteria, fungi, helminths, and protozoa, which can be transmitted and infect other zoonotic organisms. Various studies have utilised next-generation sequencing (NGS) to describe the pathogens associated with bats. Although most have characterised microbial communities in specific body fluids, few have analysed the composition and diversity of these microbial communities across different body fluids at the individual level. In this study, we employed two next-generation sequencing techniques: amplicon-based sequencing of the V4 hypervariable region of the 16S- and 18S-rRNA genes and viral metagenomics, to describe the prokaryotic, eukaryotic, and viral communities present in blood, faeces, and oral swab samples collected from two genera of bats (Carollia and Phyllostomus) in the department of Casanare, eastern Colombia. A total of 60 samples corresponding to the three bodily fluids were processed and analysed. The results indicated that the microbial communities across the body fluids were mainly composed of bacteria, fungi, protozoa, and various DNA and RNA viruses, showing a variability of microbial genera and species. The abundances, diversity metrics, and correlations of these microorganisms displayed patterns associated with bat genus and body fluids, suggesting that the ecological characteristics of these microbial communities may be influenced by the ecological and physiological traits of the bats. Additionally, we found similar community compositions of bacteria, some fungal genera, and viruses in the three body fluids, indicating a possible circulation of these microbes within the same bat. This could be due to microbial movement from the gut microbiota to other physiological systems or transmission via blood-feeding vectors. Furthermore, our results revealed the presence of various microbes of public health concern, including Bartonella spp., Mannheimia haemolytica, Rhodotorula spp., Piroplasmida spp., Toxoplasma gondii, Alphacoronavirus spp., and Bat circovirus. The abundance of these pathogenic microbial species across the three bodily fluids suggests potential transmission routes from bats to other organisms, which may contribute to the emergence of zoonotic disease outbreaks. These findings highlight the variability of microorganisms present within the same bat and the different pathogen-host interactions that may regulate the presence and transmission of these zoonotic microbes. Further research is required to elucidate the genomic features, ecological interactions, and biological activities of these microbial communities in bats., (© 2024. The Author(s).)
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- 2024
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13. Ocular thelaziosis ( Thelazia lacrymalis ) in a harpy eagle ( Harpia harpyja ) from Colombia.
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Bonilla-Aldana JL, Ganem-Galindo NC, Estrada-Cely GE, Losada-Cordoba ML, Sarmiento-Gantiva S, Muñoz M, Ramírez AL, Patiño LH, Ramírez JD, Paniz-Mondolfi AE, Rodriguez-Morales AJ, and Bonilla-Aldana DK
- Abstract
Competing Interests: 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.
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- 2024
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14. Global and genetic diversity of SARS-CoV-2 in wastewater.
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Patiño LH, Ballesteros N, Muñoz M, Ramírez AL, Castañeda S, Galeano LA, Hidalgo A, Paniz-Mondolfi A, and Ramírez JD
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The analysis of SARS-CoV-2 in wastewater has enabled us to better understand the spread and evolution of the virus worldwide. To deepen our understanding of its epidemiological and genomic characteristics, we analyzed 10,147 SARS-CoV-2 sequences from 5 continents and 21 countries that were deposited in the GISAID database up until January 31, 2023. Our results revealed over 100 independent lineages of the virus circulating in water samples from March 2020 to January 2023, including variants of interest and concern. We observed four clearly defined periods of global distribution of these variants over time, with one variant being replaced by another. Interestingly, we found that SARS-CoV-2 water-borne sequences from different countries had a close phylogenetic relationship. Additionally, 40 SARS-CoV-2 water-borne sequences from Europe and the USA did not show any phylogenetic relationship with SARS-CoV-2 human sequences. We also identified a significant number of non-synonymous mutations, some of which were detected in previously reported cryptic lineages. Among the countries analyzed, France and the USA showed the highest degree of sequence diversity, while Austria reported the highest number of genomes (6,296). Our study provides valuable information about the epidemiological and genomic diversity of SARS-CoV-2 in wastewater, which can be employed to support public health initiatives and preparedness., Competing Interests: 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., (© 2024 The Authors.)
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- 2024
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15. Cytotoxicity Activity of Some meso-Dihydroguaiaretic Acid Derivatives and Mode of Action of the Most Active Compound.
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Domínguez-Chavarría JA, García A, Romo-Mancillas A, Reyes-Melo KY, Chávez-Villareal KG, Vázquez-Ramírez AL, Ávalos-Alanís FG, Cabral-Romero C, Hernández-Delgadillo R, García-Cuellar CM, and Del Rayo Camacho-Corona M
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- Male, Humans, Structure-Activity Relationship, Drug Screening Assays, Antitumor, Cell Proliferation, Molecular Structure, Molecular Docking Simulation, Cell Line, Tumor, MCF-7 Cells, Antineoplastic Agents pharmacology, Lignans pharmacology, Guaiacol analogs & derivatives
- Abstract
The aim of this study was to screen sixteen meso-1 semi-synthetic derivatives bearing ether, esther, carbamate, phosphate or aminoether functional groups against five cancer cell lines: MCF-7 (breast), A549 (lung), HepG2 (liver), HeLa (cervix), and DU145 (prostate) at 25 μM using the MTT assay. Results from the screening showed that two derivatives had the lowest percentage of cell viability at 25 μM, the aminoether derivative meso-11 and the esther derivative meso-20 against A549 (44.15±0.78 %) and MCF-7 (41.60±0.92 %), respectively. Then, it was determined the IC
50 value of each compound against their most sensitive cancer cell line. Results showed that aminoether derivative meso-11 showed potent cytotoxicity against A549 (IC50 =17.11±2.11 μM), whereas it resulted more cytotoxic against the LL-47 lung normal cell line (IC50 =9.49±1.19 μM) having a Selective Index (SI) of 0.55. On the other hand, the esther derivative meso-20 exhibited potent activity against MCF-7 (IC50 =18.20±1.98 μM), whereas it displayed moderate cytotoxicity against the MCF-10 breast normal cell line (IC50 =41.22±2.17 μM) with a SI of 2.2. Finally, studies on the mechanism of action of meso-20 indicated disruption of MCF-7 plasma membrane in vitro and the AMPK activation in silico., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)- Published
- 2024
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16. High prevalence of Enterovirus E, Bovine Kobuvirus, and Astrovirus revealed by viral metagenomics in fecal samples from cattle in Central Colombia.
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Medina JE, Castañeda S, Páez-Triana L, Camargo M, Garcia-Corredor DJ, Gómez M, Luna N, Ramírez AL, Pulido-Medellín M, Muñoz M, and Ramírez JD
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- Humans, Animals, Cattle, Phylogeny, Prevalence, Colombia epidemiology, Feces, Metagenomics, Viruses, Astroviridae genetics, Enterovirus, Kobuvirus
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Livestock plays a crucial role in ensuring food security and driving the global economy. However, viral infections can have far-reaching consequences beyond economic productivity, affecting the health of cattle, as well as posing risks to human health and other animals. Identifying viruses present in fecal samples, a primary route of pathogen transmission, is essential for developing effective prevention, control, and surveillance strategies. Viral metagenomic approaches offer a broader perspective and hold great potential for detecting previously unknown viruses or uncovering previously undescribed agents. Ubaté Province is Colombia's dairy capital and a key center for livestock production in the country. Therefore, the purpose of this study was to characterize viral communities in fecal samples from cattle in this region. A total of 42 samples were collected from three municipalities in Ubaté Province, located in central Colombia, using a convenient non-probabilistic sampling method. We utilized metagenomic sequencing with Oxford Nanopore Technologies (ONT), combined with diversity and phylogenetic analysis. The findings revealed a consistent and stable viral composition across the municipalities, primarily comprising members of the Picornaviridae family. At the species level, the most frequent viruses were Enterovirus E (EVE) and Bovine Astrovirus (BoAstV). Significantly, this study reported, for the first time in Colombia, the presence of viruses with veterinary importance occurring at notable frequencies: EVE (59%), Bovine Kobuvirus (BKV) (52%), and BoAstV (19%). Additionally, the study confirmed the existence of Circular replicase-encoding single-stranded (CRESS) Virus in animal feces. These sequences were phylogenetically grouped with samples obtained from Asia and Latin America, underscoring the importance of having adequate representation across the continent. The virome of bovine feces in Ubaté Province is characterized by the predominance of potentially pathogenic viruses such as BoAstV and EVE that have been reported with substantial frequency and quantities. Several of these viruses were identified in Colombia for the first time. This study showcases the utility of using metagenomic sequencing techniques in epidemiological surveillance. It also paves the way for further research on the influence of these agents on bovine health and their frecuency across the country., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Juan David Ramirez reports financial support was provided by University of Rosario., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2024
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17. In Silico and In Vivo Evaluation of the Maqui Berry ( Aristotelia chilensis (Mol.) Stuntz) on Biochemical Parameters and Oxidative Stress Markers in a Metabolic Syndrome Model.
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Castillo-García EL, Cossio-Ramírez AL, Córdoba-Méndez ÓA, Loza-Mejía MA, Salazar JR, Chávez-Gutiérrez E, Bautista-Poblet G, Castillo-Mendieta NT, Moreno DA, García-Viguera C, Pinto-Almazán R, Almanza-Pérez JC, Gallardo JM, and Guerra-Araiza C
- Abstract
Metabolic syndrome (MetS) is a complex disease that includes metabolic and physiological alterations in various organs such as the heart, pancreas, liver, and brain. Reports indicate that blackberry consumption, such as maqui berry, has a beneficial effect on chronic diseases such as cardiovascular disease, obesity, and diabetes. In the present study, in vivo and in silico studies have been performed to evaluate the molecular mechanisms implied to improve the metabolic parameters of MetS. Fourteen-day administration of maqui berry reduces weight gain, blood fasting glucose, total blood cholesterol, triacylglycerides, insulin resistance, and blood pressure impairment in the diet-induced MetS model in male and female rats. In addition, in the serum of male and female rats, the administration of maqui berry (MB) improved the concentration of MDA, the activity of SOD, and the formation of carbonyls in the group subjected to the diet-induced MetS model. In silico studies revealed that delphinidin and its glycosylated derivatives could be ligands of some metabolic targets such as α-glucosidase, PPAR-α, and PPAR-γ, which are related to MetS parameters. The experimental results obtained in the study suggest that even at low systemic concentrations, anthocyanin glycosides and aglycones could simultaneously act on different targets related to MetS. Therefore, these molecules could be used as coadjuvants in pharmacological interventions or as templates for designing new multitarget molecules to manage patients with MetS.
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- 2023
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18. n-3 Polyunsaturated Fatty Acid Supplementation Affects Oxidative Stress Marker Levels in Patients with Type II Intestinal Failure: A Randomized Double Blind Trial.
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Flores-López A, Guevara-Cruz M, Avila-Nava A, González-Garay AG, González-Salazar LE, Reyes-Ramírez AL, Pedraza-Chaverri J, Medina-Campos ON, Medina-Vera I, Reyes-García JG, Tovar AR, and Serralde-Zúñiga AE
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Type II intestinal failure (IF-II) is a condition in which the gastrointestinal tract is compromised. Liver complications may occur because of the pathology and/or prolonged use of parenteral nutrition (PN); oxidative stress has been implicated as one of the causes. Lipid emulsions containing n-3 polyunsaturated fatty acids (PUFAs) have been proposed for the treatment. We aimed to evaluate the effect of 7-day n-3 PUFA supplementation on oxidative stress in IF-II patients receiving PN. This was a randomized, controlled, double-blinded, pilot trial of adult patients with IF-II, receiving either conventional PN (control) or PN enriched with n-3 PUFAs (intervention). Twenty patients were included (14 men, 49 ± 16.9 years), with the ANCOVA analysis the glucose ( p = 0.003), and direct bilirubin ( p = 0.001) levels reduced; whereas the high-density lipoprotein cholesterol (HDL-C) increased ( p = 0.017). In the random-effect linear regression analysis, a reduction ( p < 0.0001) in the malondialdehyde (MDA) level was found in the intervention group when the covariables age, HDL-C level, and alanine aminotransferase activity were considered. After 1 week of PN supplementation with n-3 PUFAs, the marker levels of some oxidative stress, blood lipids, and hepatic biomarkers improved in patients with IF-II.
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- 2023
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19. Mu SARS-CoV-2 (B.1.621) variant: A genomic snapshot across the Colombian-Venezuelan border.
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Patiño LH, Ballesteros N, Muñoz M, Ramírez AL, Luna N, Castañeda S, Gutierrez-Marin R, Mendoza-Ibarra JA, Rodriguez R, Bohada DP, Ramírez JD, and Paniz-Mondolfi A
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- Humans, Colombia epidemiology, Genomics, SARS-CoV-2 genetics, COVID-19 epidemiology
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- 2023
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20. Human influenza A virus H1N1 in marine mammals in California, 2019.
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Plancarte M, Kovalenko G, Baldassano J, Ramírez AL, Carrillo S, Duignan PJ, Goodfellow I, Bortz E, Dutta J, van Bakel H, and Coffey LL
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- Animals, Humans, California epidemiology, Influenza A Virus, H1N1 Subtype, Caniformia, Influenza A virus, Seals, Earless, Influenza, Human epidemiology
- Abstract
From 2011-2018, we conducted surveillance in marine mammals along the California coast for influenza A virus (IAV), frequently detecting anti-influenza antibodies and intermittently detecting IAV. In spring 2019, this pattern changed. Despite no change in surveillance intensity, we detected IAV RNA in 10 samples in March and April, mostly in nasal and rectal swabs from northern elephant seals (Mirounga angustirostris). Although virus isolation was unsuccessful, IAV sequenced from one northern elephant seal nasal swab showed close genetic identity with pandemic H1N1 IAV subclade 6B.1A.1 that was concurrently circulating in humans in the 2018/19 influenza season. This represents the first report of human A(H1N1)pdm09 IAV in northern elephant seals since 2010, suggesting IAV continues to spill over from humans to pinnipeds., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Plancarte et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2023
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21. A Landscape of the Genomic Structure of Cryptococcus neoformans in Colombian Isolates.
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Patiño LH, Muñoz M, Ramírez AL, Vélez N, Escandón P, Parra-Giraldo CM, and Ramírez JD
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Cryptococcus neoformans species complexes are recognized as environmental fungi responsible for lethal meningoencephalitis in immunocompromised individuals. Despite the vast knowledge about the epidemiology and genetic diversity of this fungus in different regions of the world, more studies are necessary to comprehend the genomic profiles across South America, including Colombia, considered to be the second country with the highest number of Cryptococcosis. Here, we sequenced and analyzed the genomic architecture of 29 Colombian C. neoformans isolates and evaluated the phylogenetic relationship of these strains with publicly available C. neoformans genomes. The phylogenomic analysis showed that 97% of the isolates belonged to the VNI molecular type and the presence of sub-lineages and sub-clades. We evidenced a karyotype without changes, a low number of genes with copy number variations, and a moderate number of single-nucleotide polymorphisms (SNPs). Additionally, a difference in the number of SNPs between the sub-lineages/sub-clades was observed; some were involved in crucial fungi biological processes. Our study demonstrated the intraspecific divergence of C. neoformans in Colombia. These findings provide evidence that Colombian C. neoformans isolates do not probably require significant structural changes as adaptation mechanisms to the host. To the best of our knowledge, this is the first study to report the whole genome sequence of Colombian C. neoformans isolates.
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- 2023
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22. [Impact of primary dysmenorrhea on the academic performance of university students].
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Ortiz MI, Espinoza-Ramírez AL, Cariño-Cortés R, and Moya-Escalera A
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- Adolescent, Adult, Cross-Sectional Studies, Dysmenorrhea epidemiology, Dysmenorrhea psychology, Female, Humans, Universities, Young Adult, Academic Performance, Students, Medical
- Abstract
Objective: Primary dysmenorrhea has a high prevalence among the student population. The objective of this study was to determine the prevalence of dysmenorrhea, its severity and its impact on academic performance in Mexican university students., Methods: Cross-sectional study. An anonymous multiple-choice questionnaire was applied in class hours in the classrooms. The visual pain scale (VAS) was used for the measurement of pain. A descriptive and inferential analysis of the variables studied was carried out using the program SPSS® IBM., Results: A total of 2154 (n=2154) students were surveyed. The average age of the women was 20.4 ±1.9years. The general prevalence of dysmenorrhea was 78.9%, with psychology students having the highest value (83.7%). The VAS mean pain score was of 64.0. The severity of menstrual pain in students was reported as mild in 9.0%, and moderate-severe in 91.0%. The VAS mean pain scores and intensity of pain of gerontology students were significantly higher than those reported by dentistry and medicine students (P<.05). Limitation of daily activities was reported in 90.4% of women, with medical students reporting the highest percentage (93.3%). Women reported school absenteeism in 37.0%, with medical students presenting the highest percentage (41.4%). The severity of menstrual pain as a risk factor (independent variable) positively influenced various dependent variables involved in students' academic performance (P<.05), including: stop doing their activities due to pain in 1 to 6 menstruations a year, minor concentration, absenteeism, low school performance, and lower grades during dysmenorrhea., Conclusion: A high prevalence of dysmenorrhea was observed and it is concluded that the severity of the symptomatology significantly interferes with the academic performance of the participants., (Copyright © 2022 Elsevier España, S.L.U. All rights reserved.)
- Published
- 2022
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23. Phylogenomic analysis of the monkeypox virus (MPXV) 2022 outbreak: Emergence of a novel viral lineage?
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Luna N, Ramírez AL, Muñoz M, Ballesteros N, Patiño LH, Castañeda SA, Bonilla-Aldana DK, Paniz-Mondolfi A, and Ramírez JD
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- Humans, Disease Outbreaks, Phylogeny, Mpox (monkeypox) virology, Monkeypox virus genetics
- Abstract
Monkeypox is a zoonotic disease with clinical manifestations similar to smallpox in humans. Since May 13, 2022, an increasing number of suspected and confirmed cases have been reported, affecting non-endemic regions across the globe. More strikingly, reports from the current outbreak reveal unique aspects regarding transmission dynamics and an unprecedented, rapidly expanding and sustained community transmission. As demonstrated through the still-ongoing COVID-19 pandemic, genomic surveillance has been an essential resource for monitoring and tracking the evolution of pathogens of public health relevance. Herein, we performed a phylogenomic analysis of available Monkeypox virus (MPXV) genomes to determine their evolution and diversity. Our analysis revealed that all MPXV genomes grouped into three monophyletic clades: two previously characterized clades and a newly emerging clade harboring genomes from the ongoing 2022 multi-country outbreak with 286 genomes comprising the hMPXV-1A clade and the newly classified lineages: A.1 (n = 6), A.1.1 (n = 1), A.2 (n = 3) and B.1 (n = 262), where lineage B.1 includes all MPXV genomes from the 2022 outbreak. Finally, it was estimated that B.1 lineage of this clade emerged in Europe on 03/02/2022 [95%CI = 11/13/2021 to 05/10/2022]. The exceptional surge of cases and the broader geographical expansion suggest multifactorial factors as drivers of the current outbreak dynamics. Such factors may include the cessation of smallpox vaccination and its potential spread across particular networks. Integrating pertinent epidemiological information with genomic surveillance information will help generate real-time data to help implement adequate preventive and control measures by optimizing public health decisions to mitigate this outbreak., Competing Interests: Declaration of competing interest Nothing to declare., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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24. Genomic Diversity of SARS-CoV-2 Omicron Variant in South American Countries.
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Luna N, Muñoz M, Ramírez AL, Patiño LH, Castañeda SA, Ballesteros N, and Ramírez JD
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- Genomics, Humans, Phylogeny, South America epidemiology, COVID-19 epidemiology, SARS-CoV-2 genetics
- Abstract
Genomic surveillance of SARS-CoV-2 is one of the tools that provide genomic information on circulating variants. Given the recent emergence of the Omicron (B.1.1.529) variant, this tool has provided data about this lineage's genomic and epidemiological characteristics. However, in South America, this variant's arrival and genomic diversity are scarcely known. Therefore, this study determined the genomic diversity and phylogenetic relationships of 21,615 Omicron genomes available in public databases. We found that in South America, BA.1 (n = 15,449, 71%) and BA.1.1 (n = 6257, 29%) are the dominant sublineages, with several mutations that favor transmission and antibody evasion. In addition, these lineages showed cryptic transmission arriving on the continent in late September 2021. This event may have contributed to the dispersal of Omicron sublineages and the acquisition of new mutations. Considering the genomic and epidemiological characteristics of these lineages, especially those with a high number of mutations in their genome, it is important to conduct studies and surveillance on the dynamics of these lineages to identify the mechanisms of mutation acquisition and their impact on public health.
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- 2022
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25. Describing the intestinal microbiota of Holstein Fasciola-positive and -negative cattle from a hyperendemic area of fascioliasis in central Colombia.
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Ramírez AL, Herrera G, Muñoz M, Vega L, Cruz-Saavedra L, García-Corredor D, Pulido-Medellín M, Bulla-Castañeda DM, Giraldo JC, Bernal MC, Fernández-Manrique J, Vásquez-Arteaga LR, and Ramírez JD
- Subjects
- Animals, Biomarkers, Cattle, Cattle Diseases parasitology, Colombia, Enzyme-Linked Immunosorbent Assay, Fascioliasis parasitology, High-Throughput Nucleotide Sequencing, RNA, Ribosomal, 16S genetics, RNA, Ribosomal, 18S genetics, Sensitivity and Specificity, Antibodies, Helminth blood, Fasciola hepatica immunology, Fascioliasis diagnosis, Feces microbiology, Gastrointestinal Microbiome genetics
- Abstract
The ability to identify compositional changes in the intestinal microbiota of parasitized hosts is important for understanding the physiological processes that may affect animal productivity. Within the field of host-parasite interactions, many studies have suggested that helminths can influence the microbial composition of their hosts via their immunomodulatory effects. Bovine fascioliasis is a helminthiasis widely studied by immunologists, but with little information available regarding gut microbial communities. Thus, we aimed to describe the composition of the intestinal microbiota of Holstein Fasciola-positive and -negative cattle using parasitological methods and ELISA (enzyme-linked immunosorbent assay). Bovine fecal samples (n = 65) were obtained from livestock slaughter plants in the Cundi-Boyacense Colombian highlands (a hyperendemic region for bovine fascioliasis) and studied by amplicon-based next-generation 16S-rRNA and 18S-rRNA gene sequencing. From these samples, 35 were Fasciola hepatica-negative and, 30 were F. hepatica-positive in our detection analysis. Our results showed a reduction in the relative abundance of Bacteroidetes and Ascomycota in the Fasciola-positive samples, along with decreased relative abundances of the commensal taxa previously associated with fermentation and digestion processes. However, metabolomic approaches and functional analyzes of the intestinal microbiota are necessary to support these hypothesis. These findings are a small first step in the development of research aimed at understanding how microbial populations in bovines are modulated in liver helminth infections., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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26. Management of Procedural Pain in Children.
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Páramo-Cano T, Ortiz MI, Gómez-Busto FJ, and Espinoza-Ramírez AL
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- Adult, Child, Humans, Pain, Procedural diagnosis, Pain, Procedural therapy
- Abstract
In recent years, there has been increased interest in the study of pain in children and its treatment. It is known that when facing diagnostic and therapeutic procedures similar to those performed on adults, children either do not receive specific pain treatment or receive it on a significantly lower scale. However, recent research suggests a change in attitude and an improvement in the current treatment of children's pain. Although current knowledge demonstrates the falsity of many preconceived ideas about pain and its management, our results suggest that attitudinal change towards childhood pain remains slow and that real improvement in the training and practical application of the pediatrician who has to treat childhood pain is urgently needed. In this context, this manuscript has prepared standards and guidelines to improve pain management practices in a large number of national and international professional settings., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2021
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27. Adaptation of the medical-nutrition therapy for patients with intestinal failure in a developing country: A modified Delphi survey.
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Rosas-Flota X, Castillo-Martínez L, Reyes-Ramírez AL, Martínez-Soto Holguín MC, and Serralde-Zúñiga AE
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- Consensus, Delphi Technique, Humans, Surveys and Questionnaires, Developing Countries, Nutrition Therapy
- Abstract
Background & Aims: Intestinal Failure (IF) is a complex disease with huge impacts on our society due to complications. Therefore, in a developing country like Mexico without specialized IF clinics, health care professionals must provide evidence-based interventions for the IF patient. This study aims to achieve consensus on how to adapt the existing guidelines for IF to the local practices considering the available resources and local practices., Methods: A three-round modified Delphi process was used to build consensus on the most important interventions for our IF patients. For each round, data was collected and consensus was defined as ≥80% of agreement for each item. Descriptive statistics were used to determine whether a consensus was achieved., Results: Ten content experts completed the three-round modified Delphi survey. Consensus was achieved for 98% of the items related to the hospitalized patient, ambulatory care management, and drug therapy. Some of these items are not included in the ESPEN guidelines for IF, but we considered that they are relevant in our clinical practice, like the calculation of fluids for patients with very low body weight, screening for refeeding syndrome and the use of some conventional drugs to promote intestinal rehabilitation., Conclusions: Using a three-round modified Delphi process, consensus was achieved for nearly all items. This represents a starting point for the improvement of our local practices towards this complex disease, leading to better outcomes and the implementation of evidence-based protocolized interventions which can have an important impact due to the lack of access to some of the most novel pharmacological therapies like the glucagon-like-peptide (GLP-2) analog., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2020 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2020
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28. Two Sides of a Coin: a Zika Virus Mutation Selected in Pregnant Rhesus Macaques Promotes Fetal Infection in Mice but at a Cost of Reduced Fitness in Nonpregnant Macaques and Diminished Transmissibility by Vectors.
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Lemos D, Stuart JB, Louie W, Singapuri A, Ramírez AL, Watanabe J, Usachenko J, Keesler RI, Sanchez-San Martin C, Li T, Martyn C, Oliveira G, Saraf S, Grubaugh ND, Andersen KG, Thissen J, Allen J, Borucki M, Tsetsarkin KA, Pletnev AG, Chiu CY, Van Rompay KKA, and Coffey LL
- Subjects
- Aedes virology, Animals, Chlorocebus aethiops, Disease Outbreaks, Female, Humans, Macaca mulatta, Male, Mice, Mice, Inbred C57BL, Mosquito Vectors virology, Pregnancy, Vero Cells, Viral Nonstructural Proteins, Viremia, Zika Virus growth & development, Mutation, Pregnancy Complications, Infectious virology, Zika Virus genetics, Zika Virus Infection virology
- Abstract
Although fetal death is now understood to be a severe outcome of congenital Zika syndrome, the role of viral genetics is still unclear. We sequenced Zika virus (ZIKV) from a rhesus macaque fetus that died after inoculation and identified a single intrahost substitution, M1404I, in the ZIKV polyprotein, located in nonstructural protein 2B (NS2B). Targeted sequencing flanking position 1404 in 9 additional macaque mothers and their fetuses identified M1404I at a subconsensus frequency in the majority (5 of 9, 56%) of animals and some of their fetuses. Despite its repeated presence in pregnant macaques, M1404I has occurred rarely in humans since 2015. Since the primary ZIKV transmission cycle is human-mosquito-human, mutations in one host must be retained in the alternate host to be perpetuated. We hypothesized that ZIKV I1404 increases viral fitness in nonpregnant macaques and pregnant mice but is less efficiently transmitted by vectors, explaining its low frequency in humans during outbreaks. By examining competitive fitness relative to that of ZIKV M1404, we observed that ZIKV I1404 produced lower viremias in nonpregnant macaques and was a weaker competitor in tissues. In pregnant wild-type mice, ZIKV I1404 increased the magnitude and rate of placental infection and conferred fetal infection, in contrast to ZIKV M1404, which was not detected in fetuses. Although infection and dissemination rates were not different, Aedes aegypti mosquitoes transmitted ZIKV I1404 more poorly than ZIKV M1404. Our data highlight the complexity of arbovirus mutation-fitness dynamics and suggest that intrahost ZIKV mutations capable of augmenting fitness in pregnant vertebrates may not necessarily spread efficiently via mosquitoes during epidemics. IMPORTANCE Although Zika virus infection of pregnant women can result in congenital Zika syndrome, the factors that cause the syndrome in some but not all infected mothers are still unclear. We identified a mutation that was present in some ZIKV genomes in experimentally inoculated pregnant rhesus macaques and their fetuses. Although we did not find an association between the presence of the mutation and fetal death, we performed additional studies with ZIKV with the mutation in nonpregnant macaques, pregnant mice, and mosquitoes. We observed that the mutation increased the ability of the virus to infect mouse fetuses but decreased its capacity to produce high levels of virus in the blood of nonpregnant macaques and to be transmitted by mosquitoes. This study shows that mutations in mosquito-borne viruses like ZIKV that increase fitness in pregnant vertebrates may not spread in outbreaks when they compromise transmission via mosquitoes and fitness in nonpregnant hosts., (Copyright © 2020 Lemos et al.)
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- 2020
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29. Metagenomic Analysis of the Virome of Mosquito Excreta.
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Ramírez AL, Colmant AMG, Warrilow D, Huang B, Pyke AT, McMahon JL, Meyer DB, Graham RMA, Jennison AV, Ritchie SA, and van den Hurk AF
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- Animals, Arboviruses classification, Arboviruses isolation & purification, Australia, Genome, Viral, High-Throughput Nucleotide Sequencing, Insect Viruses isolation & purification, Metagenomics, Aedes virology, Culex virology, Feces virology, Insect Viruses classification, Virome genetics
- Abstract
Traditional screening for arboviruses in mosquitoes requires a priori knowledge and the utilization of appropriate assays for their detection. Mosquitoes can also provide other valuable information, including unexpected or novel arboviruses, nonarboviral pathogens ingested from hosts they feed on, and their own genetic material. Metagenomic analysis using next-generation sequencing (NGS) is a rapidly advancing technology that allows us to potentially obtain all this information from a mosquito sample without any prior knowledge of virus, host, or vector. Moreover, it has been recently demonstrated that pathogens, including arboviruses and parasites, can be detected in mosquito excreta by molecular methods. In this study, we investigated whether RNA viruses could be detected in mosquito excreta by NGS. Excreta samples were collected from Aedes vigilax and Culex annulirostris experimentally exposed to either Ross River or West Nile viruses and from field mosquitoes collected across Queensland, Australia. Total RNA was extracted from the excreta samples, reverse transcribed to cDNA, and sequenced using the Illumina NextSeq 500 platform. Bioinformatic analyses from the generated reads demonstrate that mosquito excreta provide sufficient RNA for NGS, allowing the assembly of near-full-length viral genomes. We detected Australian Anopheles totivirus, Wuhan insect virus 33, and Hubei odonate virus 5 and identified seven potentially novel viruses closely related to members of the order Picornavirales (2/7) and to previously described, but unclassified, RNA viruses (5/7). Our results suggest that metagenomic analysis of mosquito excreta has great potential for virus discovery and for unbiased arbovirus surveillance in the near future. IMPORTANCE When a mosquito feeds on a host, it ingests not only its blood meal but also an assortment of microorganisms that are present in the blood, thus acting as an environmental sampler. By using specific tests, it is possible to detect arthropod-borne viruses (arboviruses) like dengue and West Nile viruses in mosquito excreta. Here, we explored the use of next-generation sequencing (NGS) for unbiased detection of RNA viruses present in excreta from experimentally infected and field-collected mosquitoes. We have demonstrated that mosquito excreta provide a suitable template for NGS and that it is possible to recover and assemble near-full-length genomes of both arboviruses and insect-borne viruses, including potentially novel ones. These results importantly show the direct practicality of the use of mosquito excreta for NGS, which in the future could be used for virus discovery, environmental virome sampling, and arbovirus surveillance., (Copyright © 2020 Ramírez et al.)
- Published
- 2020
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30. Malaria surveillance from both ends: concurrent detection of Plasmodium falciparum in saliva and excreta harvested from Anopheles mosquitoes.
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Ramírez AL, van den Hurk AF, Mackay IM, Yang ASP, Hewitson GR, McMahon JL, Boddey JA, Ritchie SA, and Erickson SM
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- Animals, DNA, Protozoan genetics, Female, Malaria, Falciparum transmission, Male, Plasmodium genetics, Plasmodium falciparum genetics, Plasmodium falciparum isolation & purification, Plasmodium vivax genetics, Plasmodium vivax isolation & purification, Real-Time Polymerase Chain Reaction, Sporozoites genetics, Sporozoites isolation & purification, Anopheles parasitology, Feces parasitology, Malaria transmission, Mosquito Vectors parasitology, Plasmodium isolation & purification, Saliva parasitology
- Abstract
Background: Malaria is the most important vector-borne disease in the world. Epidemiological and ecological studies of malaria traditionally utilize detection of Plasmodium sporozoites in whole mosquitoes or salivary glands by microscopy or serological or molecular assays. However, these methods are labor-intensive, and can over- or underestimate mosquito transmission potential. To overcome these limitations, alternative sample types have been evaluated for the study of malaria. It was recently shown that Plasmodium could be detected in saliva expectorated on honey-soaked cards by Anopheles stephensi, providing a better estimate of transmission risk. We evaluated whether excretion of Plasmodium falciparum nucleic acid by An. stephensi correlates with expectoration of parasites in saliva, thus providing an additional sample type for estimating transmission potential. Mosquitoes were exposed to infectious blood meals containing cultured gametocytes, and excreta collected at different time points post-exposure. Saliva was collected on honey-soaked filter paper cards, and salivary glands were dissected and examined microscopically for sporozoites. Excreta and saliva samples were tested by real time polymerase chain reaction (RT-rtPCR)., Results: Plasmodium falciparum RNA was detected in mosquito excreta as early as four days after ingesting a bloodmeal containing gametocytes. Once sporogony (the development of sporozoites) occurred, P. falciparum RNA was detected concurrently in both excreta and saliva samples. In the majority of cases, no difference was observed between the C
t values obtained from matched excreta and saliva samples, suggesting that both samples provide equally sensitive results. A positive association was observed between the molecular detection of the parasites in both samples and the proportion of mosquitoes with sporozoites in their salivary glands from each container. No distinguishable parasites were observed when excreta samples were stained and microscopically analyzed., Conclusions: Mosquito saliva and excreta are easily collected and are promising for surveillance of malaria-causing parasites, especially in low transmission settings or in places where arboviruses co-circulate.- Published
- 2019
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31. Stability of West Nile Virus (Flaviviridae: Flavivirus) RNA in Mosquito Excreta.
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Ramírez AL, Hall-Mendelin S, Hewitson GR, McMahon JL, Staunton KM, Ritchie SA, and van den Hurk AF
- Subjects
- Animals, Culicidae virology, Feces virology, RNA, Viral analysis, West Nile virus isolation & purification
- Abstract
Arbovirus surveillance is crucial for the implementation of vector-borne disease control measures. Recently, it has been demonstrated that mosquitoes with a disseminated arbovirus infection excrete viral RNA, which can be detected by molecular methods. Thereby, mosquito excreta has been proposed as a sample type that could be utilized for arbovirus surveillance. In this study, we evaluated if West Nile virus (Kunjin strain, WNVKUN) RNA in Culex annulirostris Skuse (Diptera: Culicidae) excreta deposited on different substrates could be detected after storage for up to 2 wk at tropical conditions of high heat and humidity. No significant drop in relative quantity of WNVKUN RNA (determined by comparison of Ct values) in excreta deposited on Flinders Associate Technologies (FTA) cards was observed over 14 d, suggesting that RNA was stable for that time. There was no significant difference in relative quantity of WNVKUN RNA in excreta deposited on FTA cards or polycarbonate substrates after 24 h. However, after 7 and 14 d, there was a significant decline in the relative quantity of viral RNA in the excreta stored on polycarbonate substrates. For incorporation in arbovirus surveillance programs, we recommend the use of polycarbonate substrates for excreta collection in mosquito traps deployed overnight, and the integration of FTA cards in traps serviced weekly or fortnightly. Polycarbonate substrates facilitate the collection of the majority of excreta from a trap, and while FTA cards offer limited area coverage, they enable preservation of viral RNA in tropical conditions for extended periods of time., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2019
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32. Short article: Frequency, pathophysiology, and clinical classification of intestinal failure type II and III at a tertiary referral center.
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Rosas-Flota X, Castillo-Martínez L, Reyes-Ramírez AL, Osorio-Alamillo Y, Murguía-Vázquez M, and Serralde-Zúñiga AE
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- Adult, Aged, Cross-Sectional Studies, Energy Intake, Female, Humans, Malabsorption Syndromes epidemiology, Malabsorption Syndromes therapy, Male, Mexico epidemiology, Middle Aged, Parenteral Nutrition, Short Bowel Syndrome diagnosis, Short Bowel Syndrome physiopathology, Treatment Outcome, Intestinal Absorption, Malabsorption Syndromes diagnosis, Malabsorption Syndromes physiopathology, Nutritional Status, Short Bowel Syndrome epidemiology, Surgical Procedures, Operative adverse effects, Tertiary Care Centers
- Abstract
Objective: Intestinal failure (IF) is a complex disease that is gaining significance and attention throughout the world. In Mexico, there are no available data on this condition. The aim of this study was to determine the frequency and characteristics of patients with IF type II and III hospitalized at a tertiary referral center in our country., Patients and Methods: A cross-sectional study was carried out from August 2016 to July 2017. Adult patients hospitalized in noncritical areas with a recent diagnosis of IF type II or III according to the European Society for Clinical Nutrition and Metabolism classification were included. Demographic, anthropometric, nutritional therapy, biochemical, and clinical characteristics were registered. Nutritional risk was determined by the Nutritional Risk Score 2002., Results: During the study, 4144 patients were admitted to noncritical areas; 21 (5/1000) of these patients were included. The mean age of the patients was 51±18.8 years, and the mean BMI was 17.6±5.5 kg/m. Fifteen (71.5%) patients were diagnosed with IF type II and six (28.5%) with IF type III. The primary diagnosis was surgical complications in seven (33.3%) of the cases and the principal pathophysiological mechanism was short bowel syndrome in nine (42.8%) patients. The most frequent (37%) clinical classification was D2: more than 20 kcal/kg/day and 1001-2000 ml/day and parenteral nutrition and PN2: 1001-2000 ml/day (52.3%) based on the modified European Society for Clinical Nutrition and Metabolism clinical classification., Conclusion: In this study, a high frequency of IF was found; surgical complications and short bowel syndrome were the main mechanisms involved, and D2 was the most frequent clinical category.
- Published
- 2019
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33. Modifying the Biogents Sentinel Trap to Increase the Longevity of Captured Aedes aegypti.
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Timmins DR, Staunton KM, Meyer DB, Townsend M, Paton CJ, Ramírez AL, and Ritchie SA
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- Animals, Female, Longevity, Aedes physiology, Mosquito Control instrumentation, Mosquito Vectors physiology
- Abstract
Aedes aegypti (L.) (Diptera: Culicidae) is a vector of viruses causing dengue, Zika, chikungunya, and yellow fever and subsequently pose a significant global threat to public health. While sampling live mosquitoes is useful for surveillance purposes, most traps targeting Aedes kill captured mosquitoes. The Biogents Sentinel (BGS) trap, the gold standard for capturing Ae. aegypti, is one such trap. In our study, we modified the BGS trap to increase the survival of captured Ae. aegypti by replacing the trap's catch bag with a catch pot that protects mosquitoes from desiccation by airflow. A sucrose-soaked sponge or nucleic acid preservative card can also be placed inside the pot to enhance mosquito survival and augment arbovirus detection. These modifications to the BGS significantly increased the longevity of mosquitoes captured with weekly survivals of 93% in a semifield structure and 86% in the field. These high survival rates resulted in 3.5 times more alive Ae. aegypti captured weekly in the modified BGS compared to the original BGS, despite 40% lower overall catch rates. These cheap and simple trap modifications facilitate easier specimen identification as well as experiments requiring live field-collected samples such as virus detection from mosquito saliva and excreta.
- Published
- 2018
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34. Pneumonia in patients with systemic lupus erythematosus: Epidemiology, microbiology and outcomes.
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García-Guevara G, Ríos-Corzo R, Díaz-Mora A, López-López M, Hernández-Flores J, Fragoso-Loyo H, Ávila-Vázquez J, Pulido-Ramírez AL, Carrillo-Maravilla E, Jakez-Ocampo J, Sifuentes-Osornio J, Llorente L, and Atisha-Fregoso Y
- Subjects
- Adult, Emergency Service, Hospital, Female, Humans, Logistic Models, Lupus Erythematosus, Systemic microbiology, Male, Mexico, Multivariate Analysis, Retrospective Studies, Risk Factors, Severity of Illness Index, Tertiary Care Centers, Young Adult, Lupus Erythematosus, Systemic complications, Pneumonia mortality, Staphylococcus aureus isolation & purification
- Abstract
Background and objective Pneumonia remains the main cause of mortality in patients with systemic lupus erythematosus (SLE). The aim of the study was to establish the clinical characteristics, microbiology and risk factors for poor prognosis in patients with SLE and pneumonia. Methods We reviewed medical records of patients with SLE (American College of Rheumatology criteria) and pneumonia who attended the emergency room in a single tertiary care center (January 2010-March 2015). We collected demographics, treatment and disease activity (SLEDAI-2K) data. Severity scales of pneumonia (CURB-65 (acronym for risk factors measured: confusion, urea nitrogen, respiratory rate, blood pressure, 65 years of age and older) and Pneumonia Severity Index (PSI)) were obtained. A negative composite outcome was defined as need for mechanical ventilation, septic shock or death secondary to pneumonia up to 30 days after discharge. We conducted a univariate and multivariable analysis. Results We studied 158 patients (76% women) with 187 episodes of pneumonia. There were no differences in age, SLE duration, SLE activity, treatment or comorbidities between patients with negative composite outcome vs the other group. In 53 episodes, patients presented with a negative composite outcome. Of these, 46 (24.6%) required intubation, 13 (7%) developed shock and 12 (6.4%) died. The most common bacteria isolated was S. aureus, and we observed a high percentage of nonhabitual microorganisms. Fifteen percent of patients who presented with a negative outcome had low values on CURB-65 and PSI scales. Conclusion Patients with SLE and pneumonia have a high risk of complications and present with a high percentage of nonhabitual microorganisms. Severity scales for pneumonia can misclassify as low risk SLE patients with poor prognosis.
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- 2018
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35. Mosquito excreta: A sample type with many potential applications for the investigation of Ross River virus and West Nile virus ecology.
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Ramírez AL, Hall-Mendelin S, Doggett SL, Hewitson GR, McMahon JL, Ritchie SA, and van den Hurk AF
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- Animals, Culicidae virology, Feces virology, Ross River virus isolation & purification, West Nile virus isolation & purification
- Abstract
Background: Emerging and re-emerging arthropod-borne viruses (arboviruses) cause human and animal disease globally. Field and laboratory investigation of mosquito-borne arboviruses requires analysis of mosquito samples, either individually, in pools, or a body component, or secretion such as saliva. We assessed the applicability of mosquito excreta as a sample type that could be utilized during studies of Ross River and West Nile viruses, which could be applied to the study of other arboviruses., Methodology/principal Findings: Mosquitoes were fed separate blood meals spiked with Ross River virus and West Nile virus. Excreta was collected daily by swabbing the bottom of containers containing batches and individual mosquitoes at different time points. The samples were analyzed by real-time RT-PCR or cell culture enzyme immunoassay. Viral RNA in excreta from batches of mosquitoes was detected continuously from day 2 to day 15 post feeding. Viral RNA was detected in excreta from at least one individual mosquito at all timepoints, with 64% and 27% of samples positive for RRV and WNV, respectively. Excretion of viral RNA was correlated with viral dissemination in the mosquito. The proportion of positive excreta samples was higher than the proportion of positive saliva samples, suggesting that excreta offers an attractive sample for analysis and could be used as an indicator of potential transmission. Importantly, only low levels of infectious virus were detected by cell culture, suggesting a relatively low risk to personnel handling mosquito excreta., Conclusions/significance: Mosquito excreta is easily collected and provides a simple and efficient method for assessing viral dissemination, with applications ranging from vector competence experiments to complementing sugar-based arbovirus surveillance in the field, or potentially as a sample system for virus discovery., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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36. Searching for the proverbial needle in a haystack: advances in mosquito-borne arbovirus surveillance.
- Author
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Ramírez AL, van den Hurk AF, Meyer DB, and Ritchie SA
- Subjects
- Animals, Arbovirus Infections transmission, Arbovirus Infections virology, Arboviruses genetics, High-Throughput Nucleotide Sequencing, Humans, Sequence Analysis, DNA, Arbovirus Infections epidemiology, Arboviruses isolation & purification, Culicidae virology, Disease Outbreaks, Mosquito Vectors virology, Sentinel Surveillance
- Abstract
Surveillance is critical for the prevention and control of mosquito-borne arboviruses. Detection of elevated or emergent virus activity serves as a warning system to implement appropriate actions to reduce outbreaks. Traditionally, surveillance of arboviruses has relied on the detection of specific antibodies in sentinel animals and/or detection of viruses in pools of mosquitoes collected using a variety of sampling methods. These methods, although immensely useful, have limitations, including the need for a cold chain for sample transport, cross-reactivity between related viruses in serological assays, the requirement for specialized equipment or infrastructure, and overall expense. Advances have recently been made on developing new strategies for arbovirus surveillance. These strategies include sugar-based surveillance, whereby mosquitoes are collected in purpose-built traps and allowed to expectorate on nucleic acid preservation cards which are submitted for virus detection. New diagnostic approaches, such as next-generation sequencing, have the potential to expand the genetic information obtained from samples and aid in virus discovery. Here, we review the advancement of arbovirus surveillance systems over the past decade. Some of the novel approaches presented here have already been validated and are currently being integrated into surveillance programs. Other strategies are still at the experimental stage, and their feasibility in the field is yet to be evaluated.
- Published
- 2018
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37. Perioperative management of patients with antiphospholipid syndrome: a single-center experience.
- Author
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Atisha-Fregoso Y, Espejo-Poox E, Carrillo-Maravilla E, Pulido-Ramírez AL, Lugo Baruqui D, Hernández-Molina G, and Cabral AR
- Subjects
- Adult, Anticoagulants adverse effects, Antiphospholipid Syndrome blood, Antiphospholipid Syndrome complications, Antiphospholipid Syndrome diagnosis, Chi-Square Distribution, Drug Administration Schedule, Elective Surgical Procedures, Female, Hemorrhage chemically induced, Heparin, Low-Molecular-Weight adverse effects, Humans, Infusions, Intravenous, Male, Medical Records, Mexico, Middle Aged, Odds Ratio, Perioperative Care adverse effects, Retrospective Studies, Risk Factors, Tertiary Care Centers, Thrombosis etiology, Thrombosis prevention & control, Time Factors, Treatment Outcome, Vitamin K antagonists & inhibitors, Anticoagulants administration & dosage, Antiphospholipid Syndrome drug therapy, Blood Coagulation drug effects, Heparin, Low-Molecular-Weight administration & dosage, Perioperative Care methods, Surgical Procedures, Operative adverse effects
- Abstract
The objective was to describe the management and risk factors for complications of antiphospholipid syndrome (APS) patients who underwent a surgical procedure in a single center. We reviewed medical records of all patients with primary or secondary APS who underwent an elective surgery during a 6-year period. Demographical data, management of anticoagulation and complications were recorded. We identified 43 patients, mean age 37.9 ± 8.9 years, who underwent a total of 48 elective surgeries. All patients had history of at least one thrombotic event and were under vitamin K antagonists. Before surgery, all patients received bridging therapy with intravenous infusion of heparin or low molecular weight heparin (LMWH). Among the LMWH group, 36 had a full anticoagulation regimen and nine prophylactic doses. In 62% of the surgeries, we identified an optimal management of periprocedural anticoagulation according to guidelines. Overall six patients had severe bleeding and three thrombotic complications (full anticoagulation regimen n = 2 and prophylactic dose group n = 1). Patients with optimal management of anticoagulation experienced less thrombotic and hemorrhagic complications (7 vs. 33%; OR 0.14, 95% CI 0.02-0.81; p = 0.040) and patients with INR ≤1.5 at surgery had fewer episodes of major bleeding (6 vs. 29%; OR 0.19, 95% CI 0.02-0.98; p = 0.050). All three thrombotic events occurred in patients with INR ≤1.5. Proper management of anticoagulation based on guidelines is associated with less complications in patients with APS. Notwithstanding the proper use of bridging therapy, some patients may develop thrombotic complications.
- Published
- 2017
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38. Resistance-modifying Activity in Vinblastine-resistant Human Breast Cancer Cells by Oligosaccharides Obtained from Mucilage of Chia Seeds (Salvia hispanica).
- Author
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Rosas-Ramírez DG, Fragoso-Serrano M, Escandón-Rivera S, Vargas-Ramírez AL, Reyes-Grajeda JP, and Soriano-García M
- Subjects
- ATP Binding Cassette Transporter, Subfamily B, Member 1 metabolism, Animals, Breast Neoplasms drug therapy, Cell Line, Tumor, Chlorocebus aethiops, Humans, Seeds chemistry, Vero Cells, Breast Neoplasms pathology, Drug Resistance, Neoplasm, Oligosaccharides pharmacology, Plant Mucilage chemistry, Salvia chemistry, Vinblastine pharmacology
- Abstract
The multidrug resistance (MDR) phenotype is considered as a major cause of the failure in cancer chemotherapy. The acquisition of MDR is usually mediated by the overexpression of drug efflux pumps of a P-glycoprotein. The development of compounds that mitigate the MDR phenotype by modulating the activity of these transport proteins is an important yet elusive target. Here, we screened the saponification and enzymatic degradation products from Salvia hispanica seed's mucilage to discover modulating compounds of the acquired resistance to chemotherapeutic in breast cancer cells. Preparative-scale recycling HPLC was used to purify the hydrolysis degradation products. All compounds were tested in eight different cancer cell lines and Vero cells. All compounds were noncytotoxic at the concentration tested against the drug-sensitive and multidrug-resistant cells (IC
50 > 29.2 μM). For the all products, a moderate vinblastine-enhancing activity from 4.55-fold to 6.82-fold was observed. That could be significant from a therapeutic perspective. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)- Published
- 2017
- Full Text
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39. Origin, distribution, and potential risk factors associated with influenza A virus in swine in two production systems in Guatemala.
- Author
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Gonzalez-Reiche AS, Ramírez AL, Müller ML, Orellana D, Sosa SM, Ola P, Paniagua J, Ortíz L, Hernandez J, Cordón-Rosales C, and Perez DR
- Subjects
- Animals, Antibodies, Viral blood, Enzyme-Linked Immunosorbent Assay, Guatemala epidemiology, Hemagglutination Inhibition Tests, Hemagglutinin Glycoproteins, Influenza Virus genetics, Humans, Influenza A Virus, H1N1 Subtype classification, Influenza A Virus, H1N1 Subtype genetics, Influenza A Virus, H1N1 Subtype immunology, Influenza A Virus, H3N2 Subtype classification, Influenza A Virus, H3N2 Subtype genetics, Influenza A Virus, H3N2 Subtype immunology, Influenza, Human transmission, Influenza, Human virology, Orthomyxoviridae Infections epidemiology, Orthomyxoviridae Infections transmission, Orthomyxoviridae Infections virology, Phylogeny, Risk Factors, Spatial Analysis, Swine, Swine Diseases transmission, Swine Diseases virology, Influenza A Virus, H1N1 Subtype isolation & purification, Influenza A Virus, H3N2 Subtype isolation & purification, Influenza, Human epidemiology, Livestock virology, Orthomyxoviridae Infections veterinary, Swine Diseases epidemiology
- Abstract
Background: Guatemala is the country with the largest swine production in Central America; however, evidence of influenza A virus (IAV) in pigs has not been clearly delineated., Objectives: In this study, we analyzed the presence and spatial distribution of IAV in commercial and backyard swine populations., Methods: Samples from two nationwide surveys conducted in 2010 and 2011 were tested using virological (rRT-PCR and virus isolation) and serological (ELISA and hemagglutination inhibition) assays to detect IAV., Results: Influenza A virus was detected in 15.7% of the sampled pigs (30.6% of herds) in 2010 and in 11.7% (24.2% of herds) in 2011. The percentage of seropositive pigs was 10.6% (16.1% of herds) and 1.4% (3.1% of herds) for each year, respectively. Three pandemic H1N1 and one seasonal human-like H3N2 viruses were isolated. Antibodies against viruses from different genetic clusters were detected. No reassortant strains with swine viruses were detected. The H3N2 virus was closely related to human viruses that circulated in Central America in 2010, distinct to the most recent human seasonal vaccine lineages. Spatial clusters of rRT-PCR positive herds were detected each year by scan statistics., Conclusions: Our results demonstrate circulation of IAV throughout Guatemala and identify commercial farms, animal health status, and age as potential risk factors associated with IAV infection and exposure. Detection of human-origin viruses in pigs suggests a role for humans in the molecular epidemiology of IAV in swine in Guatemala and evidences gaps in local animal and human surveillance., (© 2016 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.)
- Published
- 2017
- Full Text
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40. N-ω-chloroacetyl-L-ornithine has in-vitro activity against cancer cell lines and in-vivo activity against ascitic and solid tumors.
- Author
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Vargas-Ramírez AL, Medina-Enríquez MM, Cordero-Rodríguez NI, Ruiz-Cuello T, Aguilar-Faisal L, Trujillo-Ferrara JG, Alcántara-Farfán V, and Rodríguez-Páez L
- Subjects
- Animals, Apoptosis drug effects, Ascites pathology, Cell Line, Tumor, Cell Movement drug effects, Humans, Male, Mice, Inbred BALB C, Neoplasms pathology, Ornithine pharmacology, Toxicity Tests, Subchronic, Xenograft Model Antitumor Assays methods, Antineoplastic Agents pharmacology, Drug Screening Assays, Antitumor methods, Neoplasms drug therapy, Ornithine analogs & derivatives
- Abstract
N-ω-chloroacetyl-L-ornithine (NCAO) is an ornithine decarboxylase (ODC) inhibitor that is known to exert cytotoxic and antiproliferative effects on three neoplastic human cancer cell lines (HeLa, MCF-7, and HepG2). Here, we show that NCAO has antiproliferative activity in 13 cancer cell lines, of diverse tissue origin from human and mice, and in a mouse cancer model in vivo. All cell lines were sensitive to NCAO after 72 h of treatment (the EC50 ranged from 1 to 50.6 µmol/l). The Ca Ski cell line was the most sensitive (EC50=1.18±0.07 µmol/l) and MDA-MB-231 was the least sensitive (EC50=50.6±0.3 µmol/l). This ODC inhibitor showed selectivity for cancer cells, exerting almost no cytotoxic effect on the normal Vero cell line (EC50>1000 µmol/l). NCAO induced apoptosis and inhibited tumor cell migration in vitro. Furthermore, in vivo, this compound (at 50 and 100 mg/kg, daily intraperitoneal injection for 7 days) exerted potent antitumor activity against both solid and ascitic tumors in a mouse model using the myeloma (Ag8) cell line. At these same two doses, the toxicological evaluation showed that NCAO has no obvious systemic toxicity. The current results suggest that the antitumor activity is exerted by apoptosis related not only to a local but also a systemic cytotoxic effect exerted by NCAO on tumor cells. The applications for NCAO as an antitumor agent may be extensive; however, further studies are needed to ascertain the antitumor activity on other types of tumor in vivo and to determine the precise molecular mechanism of its activity.
- Published
- 2016
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41. N-ω-chloroacetyl-l-ornithine, a new competitive inhibitor of ornithine decarboxylase, induces selective growth inhibition and cytotoxicity on human cancer cells versus normal cells.
- Author
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Medina-Enríquez MM, Alcántara-Farfán V, Aguilar-Faisal L, Trujillo-Ferrara JG, Rodríguez-Páez L, and Vargas-Ramírez AL
- Subjects
- Animals, Antineoplastic Agents chemical synthesis, Antineoplastic Agents chemistry, Cell Proliferation drug effects, Cells, Cultured, Chlorocebus aethiops, Dose-Response Relationship, Drug, Drug Screening Assays, Antitumor, Enzyme Activation drug effects, HeLa Cells, Hep G2 Cells, Humans, Liver drug effects, Liver enzymology, Liver metabolism, MCF-7 Cells, Male, Molecular Structure, Ornithine chemical synthesis, Ornithine chemistry, Ornithine pharmacology, Ornithine Decarboxylase Inhibitors chemical synthesis, Ornithine Decarboxylase Inhibitors chemistry, Rats, Rats, Wistar, Structure-Activity Relationship, Vero Cells, Antineoplastic Agents pharmacology, Ornithine analogs & derivatives, Ornithine Decarboxylase metabolism, Ornithine Decarboxylase Inhibitors pharmacology
- Abstract
Many cancer cells have high expression of ornithine decarboxylase (ODC) and there is a concerted effort to seek new inhibitors of this enzyme. The aim of the study was to initially characterize the inhibition properties, then to evaluate the cytotoxicity/antiproliferative cell based activity of N-ω-chloroacetyl-l-ornithine (NCAO) on three human cancer cell lines. Results showed NCAO to be a reversible competitive ODC inhibitor (Ki = 59 µM) with cytotoxic and antiproliferative effects, which were concentration- and time-dependent. The EC50,72h of NCAO was 15.8, 17.5 and 10.1 µM for HeLa, MCF-7 and HepG2 cells, respectively. NCAO at 500 µM completely inhibited growth of all cancer cells at 48 h treatment, with almost no effect on normal cells. Putrescine reversed NCAO effects on MCF-7 and HeLa cells, indicating that this antiproliferative activity is due to ODC inhibition.
- Published
- 2015
- Full Text
- View/download PDF
42. [Use of the evidence-based guidelines for management of bronchiolitis].
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Oñate Ramírez AL, Rendón Macías ME, Iglesias Leboreiro J, and Bernárdez Zapata I
- Abstract
Introduction: The aim of this study was to analyze the medical care of children<5 years of age with acute bronchiolitis in relation to the most relevant practices of evidence-based guidelines for bronchiolitis., Methods: We reviewed the charts of 197 hospitalized infants with acute bronchiolitis during 2012 to 2013 to analyse whether the guideline recommendations were used according to: American Academic of Pediatritians (AAP), Scotish Intercollegiate Guidelines Network (SIGN), Sector Salud México (SS), and Guía Práctica Clínica Bronquiolitis, España (GPCBA)., Results: We evaluated 197 patients attended by 49 pediatricians. Of the recommended actions, in 110 patients (55.8%) aspirate secretions were indicated, 105 patients (53%) received supplemental oxygen and 63 patients (31.9%) used inhaled hypertonic solution. Non-recommended actions were carried out in 166 patients (84%) who received inhaled bronchodilators, 143 patients (72%) who inhaled steroids, 110 patients (55.8%) who were prescribed antibiotics, 76 patients (38%) who had nebulization and 52 patients (26.3%) were administered systemic steroids. Physicians with<10 years of expertise prescribed more systemic steroids., Conclusions: Despite the dissemination of good clinical practice guidelines for the management of acute bronchiolitis, its adoption has not been totally completed., (Copyright © 2014 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.)
- Published
- 2014
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43. Effect of vitamin E and C supplementation on oxidative damage and total antioxidant capacity in lead-exposed workers.
- Author
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Rendón-Ramírez AL, Maldonado-Vega M, Quintanar-Escorza MA, Hernández G, Arévalo-Rivas BI, Zentella-Dehesa A, and Calderón-Salinas JV
- Subjects
- Adult, Air Pollutants, Occupational blood, Antioxidants pharmacokinetics, Ascorbic Acid blood, Ascorbic Acid pharmacokinetics, Catalase blood, Dietary Supplements, Glutathione Peroxidase blood, Glutathione Reductase blood, Humans, Lead blood, Lipid Peroxidation drug effects, Male, Occupational Exposure adverse effects, Occupational Exposure analysis, Oxidative Stress drug effects, Porphobilinogen Synthase blood, Superoxide Dismutase blood, Vitamin E blood, Vitamin E pharmacokinetics, Air Pollutants, Occupational toxicity, Antioxidants pharmacology, Ascorbic Acid pharmacology, Lead toxicity, Vitamin E pharmacology
- Abstract
The molecular response of the antioxidant system and the effects of antioxidant supplementation against oxidative insult in lead-exposed workers has not been sufficiently studied. In this work, antioxidants (vitamin E 400 IU+vitamin C 1g/daily) were supplemented for one year to 15 workers exposed to lead (73 μg of lead/dl of blood) and the results were compared with those on 19 non-lead exposed workers (6.7 μg of lead/dl). Lead intoxication was accompanied by a high oxidative damage and an increment in the erythrocyte antioxidant response due to increased activity of catalase and superoxide dismutase. Antioxidant supplementations decreased significantly the oxidative damage as well as the total antioxidant capacity induced by lead intoxication with reduction of the antioxidant enzyme activities. We conclude that antioxidant supplementation is effective in reducing oxidative damage and induces modifications in the physiopathological status of the antioxidant response in lead-exposed workers., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
44. [Hidradenoma papilliferum. Report of two cases and review of literature].
- Author
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Vázquez-Velo JA, Terán AL, and Vega-Memije ME
- Subjects
- Acrospiroma diagnosis, Acrospiroma ethnology, Acrospiroma surgery, Adult, Age Distribution, Apocrine Glands pathology, Diagnosis, Differential, Epidermal Cyst diagnosis, Female, Genital Neoplasms, Male epidemiology, Humans, Male, Middle Aged, Sex Distribution, Vulvar Diseases diagnosis, Vulvar Neoplasms diagnosis, Vulvar Neoplasms ethnology, Vulvar Neoplasms surgery, Acrospiroma pathology, Vulvar Neoplasms pathology
- Abstract
We bring two cases of hidradenoma papilliferum, rare injury. We describe the clinical, histopathological and a review of the available literature on the condition.
- Published
- 2013
45. Pioneers and Followers: Migrant Selectivity and the Development of U.S. Migration Streams in Latin America.
- Author
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Lindstrom DP and Ramírez AL
- Abstract
We present a method for dividing the historical development of community migration streams into an initial period and a subsequent takeoff stage with the purpose of systemically differentiating pioneer migrants from follower migrants. The analysis is organized around five basic research questions. First, can we empirically identify a juncture in the historical development of community-based migration that marks the transition from an initial stage of low levels of migration and gradual growth into a takeoff stage in which the prevalence of migration grows at a more accelerated rate? Second, does this juncture point exist at roughly similar migration prevalence levels across communities? Third, are first-time migrants in the initial stage (pioneers) different from first-time migrants in the takeoff stage (followers)? Fourth, what is the nature of this migrant selectivity? Finally, does the nature and degree of pioneer selectivity vary across country migration streams?
- Published
- 2010
- Full Text
- View/download PDF
46. Anisotropic linear and nonlinear optical properties from anisotropy-controlled metallic nanocomposites.
- Author
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Reyes-Esqueda JA, Rodríguez-Iglesias V, Silva-Pereyra HG, Torres-Torres C, Santiago-Ramírez AL, Cheang-Wong JC, Crespo-Sosa A, Rodríguez-Fernández L, López-Suárez A, and Oliver A
- Subjects
- Algorithms, Anisotropy, Equipment Design, Light, Metals chemistry, Models, Statistical, Models, Theoretical, Metal Nanoparticles chemistry, Nanocomposites chemistry, Optics and Photonics
- Abstract
High-energy metallic ions were implanted in silica matrices, obtaining spherical-like metallic nanoparticles (NPs) after a proper thermal treatment. These NPs were then deformed by irradiation with Si ions, obtaining an anisotropic metallic nanocomposite. An average large birefringence of 0.06 was measured for these materials in the 300-800 nm region. Besides, their third order nonlinear optical response was measured using self-diffraction and P-scan techniques at 532 nm with 26 ps pulses. By adjusting the incident light's polarization and the angular position of the nanocomposite, the measurements could be directly related to, at least, two of the three linear independent components of its third order susceptibility tensor, finding a large, but anisotropic, response of around 10(-7) esu with respect to other isotropic metallic systems. For the nonlinear optical absorption, we were able to shift from saturable to reverse saturable absorption depending on probing the Au NP's major or minor axes, respectively. This fact could be related to local field calculations and NP's electronic properties. For the nonlinear optical refraction, we passed from self-focusing to self-defocusing, when changing from Ag to Au.
- Published
- 2009
- Full Text
- View/download PDF
47. [Mechanical and metabolic reproducibility of resistance test of expiratory muscles with incremental threshold loading].
- Author
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Ferrer A, Orozco-Levi M, Gea J, Méndez R, Ramírez AL, and Broquetas JM
- Subjects
- Adult, Carbon Dioxide metabolism, Humans, Male, Oxygen metabolism, Pressure, Reproducibility of Results, Respiratory Mechanics, Respiratory Muscles metabolism, Respiratory Muscles physiology
- Abstract
Background: The study of respiratory muscle endurance has mainly focused on inspiratory muscles. A new method to measure expiratory muscle endurance, through incremental threshold loading using a weighted plunger valve, has recently been described., Objectives: To evaluate the mechanical features of the plunger valve and the reproducibility of the method from the standpoint of both mechanics and metabolism., Methods: Four untrained healthy subjects performed an incremental test with expiratory threshold loading (50 g every 2 min) on each of three non-consecutive days; each test continued until the subject could no longer open the valve. Mouth pressure was recorded continuously during each test; on the first two test days, oxygen consumption (VO2) was also measured., Results: Opening and closing pressures were the same and were independent of expiratory flow, with a linear load-pressure relationship (4 cmH2O) for every 10 g of weight). The maximal tolerated load (MTL) in the three tests was stable for two of the subjects, whereas the maximal load was reached by the other two subjects in the second and third tests, respectively. When MTL was reached in the third test, mean and peak mouth pressures (the latter expressed as percent of maximal expiratory pressure [MEP]) were 49 +/- 4% and 71 +/- 4%, respectively; the expiratory tension-time index measured at the mouth ([PMEANmouth/MEP] x [TE/Ttot]) was 0.25 +/- 0.02 (TE: expiratory time; Ttot: total time). In the first and second tests, we also measured oxygen consumption of the recruited muscles, which were mainly the expiratory muscles (VO2respmax); consumption in the last test was 213 +/- 65 ml O2/min (2.9 +/- 1.1 ml O2/kg/min). The intraindividual coefficient of variation ranged from 6.3% to 19.5% for the mechanical parameters and from 14% to 21% for the metabolic ones., Conclusions: The expiratory endurance test using a threshold valve allows quantification of muscle and metabolic reserve under incremental expiratory loads. The valve has appropriate mechanical characteristics for this purpose and reproducibility is acceptable, through the precise determination of the may require up to three tests.
- Published
- 2000
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48. Endemic fluorosis in San Luis Potosi, Mexico. I. Identification of risk factors associated with human exposure to fluoride.
- Author
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Grimaldo M, Borja-Aburto VH, Ramírez AL, Ponce M, Rosas M, and Díaz-Barriga F
- Subjects
- Adolescent, Child, Environmental Exposure statistics & numerical data, Fluorides analysis, Fluorides urine, Fluorosis, Dental etiology, Humans, Mexico epidemiology, Prevalence, Regression Analysis, Risk Factors, Severity of Illness Index, Water analysis, Water Supply standards, Environmental Exposure adverse effects, Fluorides adverse effects, Fluorosis, Dental epidemiology, Water Pollution, Chemical adverse effects
- Abstract
In order to identify risk factors associated with human exposure to fluoride in San Luis Potosi (SLP), Mexico, a biochemical and epidemiological study was carried out in 1992. Results from the analysis of fluoride sources showed that 61% of tap water samples had fluoride levels above the optimal level of 0.7-1.2 ppm. The levels were higher after boiling. In bottled water, fluoride levels ranged from 0.33 to 6.97 ppm. These sources are important since in SLP 82% of the children drink tap water, 31% also drink bottled water, 92% prepare their food with tap water, 44% boiled all the drinking water, and 91% used infant formula reconstituted with boiled water. The prevalence and severity of dental fluorosis in children (11-13 years old) increased as the concentration of water fluoride increased. At levels of fluoride in water lower than 0.7 ppm a prevalence of 69% was found for total dental fluorosis, whereas at levels of fluoride in water higher than 2.0 ppm a prevalence of 98% was found. In the same children, fluoride levels in urine were quantified. The levels increased as the concentration of water fluoride increased. Regressional analysis showed an increment of 0.54 ppm (P < 0.0001) of fluoride in urine for each ppm of fluoride in water. Fluoride urinary levels were higher in samples collected during the afternoon (1800) when compared with sample collected during the morning (1100). Taking together all these results, three risk factors for human exposure to fluoride in SLP can be identified: ambient temperature, boiled water, and food preparation with boiled water. These factors explain the prevalence of dental fluorosis in SLP.
- Published
- 1995
- Full Text
- View/download PDF
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