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Background: Global estimates for cholera annually approximate 4 million cases worldwide with 95,000 deaths. Recent outbreaks, including Haiti and Yemen, are reminders that cholera is still a global health concern. Cholera outbreaks can rapidly induce high death tolls by overwhelming the capacity of health facilities, especially in remote areas or areas of civil unrest. Recent studies demonstrated that stool specimens preserved on filter paper facilitate molecular analysis of Vibrio cholerae in resource limited settings. Specimens preserved in a rapid, low-cost, safe and sustainable manner for sequencing provides previously unavailable data about circulating cholera strains. This may ultimately provide new information to shape public policy response on cholera control and elimination. Methodology/Principal findings: Whole genome sequencing (WGS) recovered close to a complete sequence of the V. cholerae O1 genome with satisfactory genome coverage from stool specimens enriched in alkaline peptone water (APW) and V. cholerae culture isolates, both spotted on filter paper. The minimum concentration of V. cholerae DNA sufficient to produce quality genomic information was 0.02 ng/μL. The genomic data confirmed the presence or absence of genes of epidemiological interest, including cholera toxin and pilus loci. WGS identified a variety of diarrheal pathogens from APW-enriched specimen spotted filter paper, highlighting the potential for this technique to explore the gut microbiome, potentially identifying co-infections, which may impact the severity of disease. WGS demonstrated that these specimens fit within the current global cholera phylogenetic tree, identifying the strains as the 7th pandemic El Tor. Conclusions: WGS results allowed for mapping of short reads from APW-enriched specimen and culture isolate spotted filter papers this provided valuable molecular epidemiological sequence information on V. cholerae strains from remote, low-resource settings. These results identified the presence of co-infecting pathogens while providing rare insight into the specific V. cholerae strains causing outbreaks in cholera-endemic areas. [ABSTRACT FROM AUTHOR]

Background: The lack of information regarding the burden of acute bacterial meningitis in Latin America leads to a reduction in the estimated incidence rates of the disease, and impairs public health decisions on the use and follow-up of preventive interventions, particularly, the evaluation of existing vaccination policies. The use of the real-time PCR in diagnostic routine procedures has resulted in a substantial increase in confirmed bacterial meningitis cases. However, in resource-poor countries, these assays are only available in reference laboratories. Sample transportation to these laboratories is a critical constraint, as it requires specialized, high cost courier services. To overcome this barrier we evaluated the use of FTATM Elute filter paper cards for the conservation and processing of samples under normal environmental conditions, as they would be when transported from remote and under-equipped healthcare facilities to the reference centers. A total of 401 samples received in 2015 as part of Sao Paulo’s national surveillance for routine diagnosis were selected for this study. Methods: The sensitivity and specificity of real-time PCR were evaluated using fresh serum and cerebrospinal fluid (CSF) samples processed using our laboratory’s standard DNA extraction, and processing the same samples after being dried and stored on FTATM card, and DNA extracted following the manufacturer’s instructions. Results: The sensitivities for detection of Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae from CSF dried and stored on FTATM cards were 98%, 92%, and 100%, respectively, and with serum samples were 73%, 88%, and 100%, respectively. When compared to our laboratory’s standard methodology, results showed high concordance, with Kappa index ranges of 0.9877–1.00 for CSF, and 0.8004–1.00 for serum samples. Conclusion: The use of FTATM cards for CSF and serum conservation and transport represents a rapid, reliable, and cost-effective alternative that will allow obtaining valuable epidemiological information that would otherwise be lost. [ABSTRACT FROM AUTHOR]

Pyocyanin is a toxin produced by Pseudomonas aeruginosa. Here we describe a novel paper-based electrochemical sensor for pyocyanin detection, manufactured with a simple and inexpensive approach based on electrode printing on paper. The resulting sensors constitute an effective electrochemical method to quantify pyocyanin in bacterial cultures without the conventional time consuming pretreatment of the samples. The electrochemical properties of the paper-based sensors were evaluated by ferri/ferrocyanide as a redox mediator, and showed reliable sensing performance. The paper-based sensors readily allow for the determination of pyocyanin in bacterial cultures with high reproducibility, achieving a limit of detection of 95 nM and a sensitivity of 4.30 μA/μM in standard culture media. Compared to the similar commercial ceramic based sensors, it is a 2.3-fold enhanced performance. The simple in-house fabrication of sensors for pyocyanin quantification allows researchers to understand in vitro adaptation of P. aeruginosa infections via rapid screenings of bacterial cultures that otherwise are expensive and time-consuming. [ABSTRACT FROM AUTHOR]

A system capable of biocatalytic conversion of distributed sources of single carbon gases such as carbon monoxide into hydrocarbons can be highly beneficial for developing commercially viable biotechnology applications in alternative energy. Several anaerobic bacterial strains can be used for such conversion. The anaerobic carbon monoxide-fixing bacteria Clostridium ljungdahlii OTA1 is a model CO assimilating microorganism that currently requires cryogenic temperature for storage of the viable strains. If these organisms can be stabilized and concentrated in thin films in advanced porous materials, it will enable development of high gas fraction, biocomposite absorbers with elevated carbon monoxide (CO) mass transfer rate, that require minimal power input and liquid, and demonstrate elevated substrate consumption rate compared to conventional suspended cell bioreactors. We report development of a technique for dry-stabilization of C. ljungdahlii OTA1 on a paper biocomposite. Bacterial samples coated onto paper were desiccated in the presence of trehalose using convective drying and stored at 4°C. Optimal dryness was ~1g H2O per gram of dry weight (gDW). CO uptake directly following biocomposite rehydration steadily increases over time indicating immediate cellular metabolic recovery. A high-resolution Raman microspectroscopic hyperspectral imaging technique was employed to spatially quantify the residual moisture content. We have demonstrated for the first time that convectively dried and stored C. ljungdahlii strains were stabilized in a desiccated state for over 38 days without a loss in CO absorbing reactivity. The Raman hyperspectral imaging technique described here is a non-invasive characterization tool to support development of dry-stabilization techniques for microorganisms on inexpensive porous support materials. The present study successfully extends and implements the principles of dry-stabilization for preservation of strictly anaerobic bacteria as an alternative to lyophilization or spray drying that could enable centralized biocomposite biocatalyst fabrication and decentralized bioprocessing of CO to liquid fuels or chemicals. [ABSTRACT FROM AUTHOR]

H-index is the most commonly applied tool to evaluate scientific productivity. In this study, the use of the H-index to evaluate scientific production in swine veterinary medicine was explored. A database of 137 pig infectious agents was constructed, including its taxonomic division, zoonotic potential, status as emerging pathogen and whether it was OIE-listed. The H-index and the total number of citations were calculated for those pathogens, the location of the affiliation of the first author of each paper included in the H-index core was registered and, for the ten pathogens with the highest H-index, evolution over time was measured. H-index values were compared to the M quotient, A-index, G-index, HG-index and the G/H ratio. H-indices were found to be severely affected by search accuracy and the database was hand curated. Swine pathogen H-indexes were highly dispersed ranging from 0 to 106 and were generally higher for pathogens causing endemic diseases in large pig producing countries. Indeed, the three top pathogens were Escherichia coli, Porcine reproductive and respiratory syndrome virus and Porcine circovirus type 2 with H-indices 106, 95 and 85, respectively. H-indices of viruses and bacteria were significantly higher (P<0.001) than other pathogen types. Also, non-zoonotic pathogens had higher H-indices than zoonotic pathogens (p<0.009) while no differences could be found for being listed by the OIE. For emerging diseases, only non-emerging viruses had higher H-index (p = 0.02). The study of H-indexes over time revealed three general patterns and that they had increased mainly after the 1980’s. As expected, there were strong geographic patterns in terms of authorship and North America (38%) and Europe (46%) coped the majority of the papers. Finally, in order to quantify the contribution of a subject to a specific field, a new index “Deciphering Citations Organized by Subject” (Dcos) is proposed. [ABSTRACT FROM AUTHOR]

Within the context of food safety, the use of modern antimicrobial technologies to inactivate the food-borne pathogens is not infallible, as proven by the ceaseless increase in the food-borne illnesses. The extensive use of antibiotics to minimize the microbial contamination further results in the evolution of antibiotic-resistant bacterial pathogens. Moreover, some of the decontamination methods frequently used in the food industry cannot be directly applied to fresh fruits and vegetables, and RTE meals. Therefore, efforts are being made by researchers in developing a new approach so as to control the bacterial contamination. Consequently, bacteriophages have evolved as the safe, green, effective and natural alternative for treatment and complete destruction of pathogens in food industry. The review provides a general description about bacteriophages and has mainly focused on their potential use as antimicrobials during the postharvest processing of foods. Numerous research papers, review papers, book chapters and other relevant literature was used for writing this review paper. [ABSTRACT FROM AUTHOR]

Cholera rapid diagnostic tests (RDT) could play a central role in outbreak detection and surveillance in low-resource settings, but their modest performance has hindered their broad adoption. The addition of an enrichment step may improve test specificity. We describe the results of a prospective diagnostic evaluation of the Crystal VC RDT (Span Diagnostics, India) with enrichment step and of culture, each compared to polymerase chain reaction (PCR), during a cholera outbreak in South Sudan. RDTs were performed on alkaline peptone water inoculated with stool and incubated for 4–6 hours at ambient temperature. Cholera culture was performed from wet filter paper inoculated with stool. Molecular detection of Vibrio cholerae O1 by PCR was done from dry Whatman 903 filter papers inoculated with stool, and from wet filter paper supernatant. In August and September 2015, 101 consecutive suspected cholera cases were enrolled, of which 36 were confirmed by PCR. The enriched RDT had 86.1% (95% CI: 70.5–95.3) sensitivity and 100% (95% CI: 94.4–100) specificity compared to PCR as the reference standard. The sensitivity of culture versus PCR was 83.3% (95% CI: 67.2–93.6) for culture performed on site and 72.2% (95% CI: 54.8–85.8) at the international reference laboratory, where samples were tested after an average delay of two months after sample collection, and specificity was 98.5% (95% CI: 91.7–100) and 100% (95% CI: 94.5–100), respectively. The RDT with enrichment showed performance comparable to that of culture and could be a sustainable alternative to culture confirmation where laboratory capacity is limited. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis of two cluster compounds {(NH4)2[Co(H2O)6]2V10O28·4H2O (C1) and (NH4)2[Ni(H2O)6]2V10O28·4H2O (C2)} which were obtained as single crystals suitable for XRD analysis that revealed their crystallization in the monoclinic (C2/c) and triclinic (P-1) space groups, respectively. Additionally, C1 and C2 were characterized using CHN analysis and FT-IR spectroscopy and their thermal decomposition mechanisms were investigated. The antibacterial activities of both compounds were determined against three human pathogenic bacterial strains {Bacillus cereus ATCC 33,018, Escherichia coli O157:H7 and Pseudomonas aeruginosa ATCC 9027} and one phytopathogenic bacterial strain {Ralstonia solanacearum}, while drug standards {chloramphenicol and streptomycin} were used as control. The inhibitory activity and the minimum inhibitory concentration (MIC) values of the tested compounds clearly indicated higher antibacterial activities of the nickel compound against B. cereus ATCC 33,018, E. coli O157 and R. solanacearum with MIC values of 3.150, 3.150 and 6.300 mg/ml, respectively. On the other hand, (NH4)2[Co(H2O)6]2V10O28·4H2O exhibited higher antibacterial activity against P. aeruginosa ATCC 9027 (MIC value of 6.300 mg/ml) in comparison to the nickel analog. In general, the measured activities are lower than that obtained for the standards except for the higher activity given by C2 in comparison to streptomycin against the R. solanacearum strain. [ABSTRACT FROM AUTHOR]

Aims: To produce light-activated antimicrobial materials composed of the photodynamic dye phloxine B incorporated into paper or cellulose membranes and to investigate ability of these materials to decrease bacterial loads on their surfaces as well as on food surfaces that were in contact with these materials under illumination with regular white light. Methods and Results: Antimicrobial cellulose-based materials with incorporated phloxine B were produced using a layer-by-layer deposition method. Antimicrobial properties of the materials were tested in model systems as well as for decontamination of food and food contact surfaces. Pseudomonas aeruginosa, Listeria monocytogenes and Bacillus anthracis were efficiently killed by exposure of the bacterial suspension to the dye-containing material under illumination with white light, but Salmonella Typhimurium and Escherichia coli O157:H7 were only partially affected. Application of the materials for decontamination of food surfaces artificially contaminated with L. monocytogenes was shown to be ineffective, while the self-decontamination of the material surface by exposure to white light resulted in eradication of L. monocytogenes cells from the material surface. Conclusions: The developed materials showed significant self-decontaminating ability when under illumination; however, decontamination of food surfaces in contact with the developed materials was not achieved. Significance and Impact of the Study: The study demonstrates the antibacterial activity of materials with incorporated photodynamic dyes when under illumination with regular-intensity white light. Possible uses of the light-activated antimicrobial materials for food processing, as food contact surfaces, and surfaces in public areas to prevent cross-contamination are discussed. [ABSTRACT FROM AUTHOR]

Pathogenic bacteria constitute a significant threat to mankind and at the same time represent a huge reservoir of abeyant therapeutics to prevent and treat various diseases. The concept of virulence determinants has been a compelling tool in driving research in the field of bacterial pathogenesis and infectious diseases. In this review, we highlight a few virulence elements forged by the pathogens from the viewpoint of the damage-response scaffold, vandalizing the susceptible host. Seeking an alternative to target the virulence determinants heads a road map toward the exemplary molecular approach. Hence, here we explore some of the exceptional applications of the clustered regulatory interspaced short palindromic repeat (CRISPR)- based therapy and antisense RNA (asRNA) approach, which could be exploited to selectively dismantle adamant components of the pathogen's virulence machinery. To the best of our knowledge, this is the first review paper involving both CRISPR and antisense RNA technology, as an alternative strategy to evade virulence mechanisms in bacterial pathogens. [ABSTRACT FROM AUTHOR]

Background: Nigeria has one of the highest burdens of pneumococcal disease in the world, but accurate surveillance is lacking. Molecular detection of infectious pathogens in dried blood spots (DBS) is an ideal method for surveillance of infections in resource-limited settings because of its low cost, minimal blood volumes involved, and ease of storage at ambient temperature. Our study aim was to evaluate a Streptococcus pneumoniae real-time polymerase chain reaction (rt-PCR) assay on DBS from febrile Nigerian children on Whatman 903 and FTA filter papers, compared to the gold standard of culture. Methods: Between September 2011 to May 2015, blood was collected from children 5 years of age or under who presented to six hospital study sites throughout northern and central Nigeria with febrile illness, and inoculated into blood culture bottles or spotted onto Whatman 903 or FTA filter paper. Culture and rt-PCR were performed on all samples. Results: A total of 537 DBS specimens from 535 children were included in the study, of which 15 were culture-positive for S. pneumoniae. The rt-PCR assay detected S. pneumoniae in 12 DBS specimens (2.2%). One positive rt-PCR result was identified in a culture-negative specimen from a high-risk subject, and two positive rt-PCR results were negative on repeat testing. Six culture-confirmed cases of S. pneumoniae bacteremia were missed. Compared to culture, the overall sensitivities of Whatman 903 and FTA DBS for detection of S. pneumoniae were 57.1% (95% CI 18.4–90.1%) and 62.5% (95% CI 24.5–91.5%), respectively. Nonspecific amplification was noted in an additional 22 DBS (4.1%). Among these, six were positive for a non-S. pneumoniae pathogen on culture. Conclusions: Rt-PCR was able to detect S. pneumoniae from clinical DBS specimens, including from a culture-negative specimen. Our findings show promise of this approach as a surveillance diagnostic, but also raise important cautionary questions. Several DBS specimens were detected as S. pneumoniae by rt-PCR despite growth of a non-S. pneumoniae pathogen on culture. A precise definition of what constitutes a positive result is required to avoid falsely over-identifying specimens. [ABSTRACT FROM AUTHOR]

Introduction: Despite evidence of the high prevalence of antibiotic resistant infections in developing countries, studies on the clinical and economic impact of antibiotic resistance (ABR) to inform interventions to contain its emergence and spread are limited. The aim of this study was to analyze the published literature on the clinical and economic implications of ABR in developing countries. Methods: A systematic search was carried out in Medline via PubMed and Web of Sciences and included studies published from January 01, 2000 to December 09, 2016. All papers were considered and a quality assessment was performed using the Newcastle-Ottawa quality assessment scale (NOS). Results: Of 27 033 papers identified, 40 studies met the strict inclusion and exclusion criteria and were finally included in the qualitative and quantitative analysis. Mortality was associated with resistant bacteria, and statistical significance was evident with an odds ratio (OR) 2.828 (95%CI, 2.231–3.584; p = 0.000). ESKAPE pathogens was associated with the highest risk of mortality and with high statistical significance (OR 3.217; 95%CIs; 2.395–4.321; p = 0.001). Eight studies showed that ABR, and especially antibiotic-resistant ESKAPE bacteria significantly increased health care costs. Conclusion: ABR is associated with a high mortality risk and increased economic costs with ESKAPE pathogens implicated as the main cause of increased mortality. Patients with non-communicable disease co-morbidities were identified as high-risk populations. [ABSTRACT FROM AUTHOR]

This paper presents a pioneer study on the microbial diversity and antibacterial potential of hive bees (Apiscerana and A.mellifera) honey collected from Himachal Pradesh. In total, 26 bacteria (14 from A.cerana and 12 from A.mellifera) but no fungal isolate were recovered. Bee species and locations comparison in terms of bacterial load (log CFU/g) revealed maximum loads of 3.74 and 3.99 in the honey from A.cerana and Mandi location, respectively. The most prevalent strains (HC3, HC5, HC6, HC8 and HM2) were identified (16S rRNA ribotyping) as Staphylococcushaemolyticus (MT742636), "Bacillussubtilis subsp. stecoris" (MT742637), Bacillussafensis subsp. safensis (MT742638), "Bacilluszanthoxyli" (MT742639) and Bacillussafensis subsp. safensis (MT938911). The apiary honey displayed good to excellent inhibitory activity against Escherichiacoli ATCC1041 whereas, fair to good against Bacillussubtilis ATCC6633, Pseudomonasaeruginosa ATCC10662, Salmonellatyphi NCTC786 and Klebsiellapneumoniae ATCC13883, highlighting its use as a therapeutic agent. Furthermore, it can be effective in minimizing numerous side effects associated with the consumption of synthetic drugs for treating bacterial infections thereby signifying the role of honey as a healthier substitute for synthetic drugs. [ABSTRACT FROM AUTHOR]

The study had two objectives : (1) to confirm the elevations of vaginal PH expected in patients with bacterial pathogens in premenopausal women and (2) to examine the relationship of serum FSH and estradiol levels to vaginal PH in postmenopause patients without bacterial pathogens. Vaginal PH was determined by universal indicator PH paper in 182 patients seen in Al-Zahara`a Hospital in Najaf city for routine speculum examination. None of the patients were pregnant. Measurements were made of serum levels of follicle – stimulating hormone and estradiol for 81 patients and vaginal culture were taken for all 182 patients. Vaginal PH was correlated with vaginal cultures and serum follicle – stimulating hormone and estradiol levels by use of statistical analysis. Vaginal PH was elevated in all premenopausal patients with documented bacterial pathogens. Serum estradiol levels showed an inverse and serum follicle – stimulating hormone levels a direct statistical correlation with vaginal PH in postmenopausal patients. [ABSTRACT FROM AUTHOR]

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SCCmec elements are very important mobile genetic elements in Staphylococci that carry beta-lactam resistance genes mecA/mecC, recombinase genes and a variety of accessory genes. Twelve main types and a couple of variants have yet been described. In addition, there are also other SCC elements harbouring other markers. In order to subtype strains of methicillin-resistant S. aureus (MRSA) based on variations within their SCCmec elements, 86 markers were selected from published SCC sequences for an assay based on multiplexed primer extension reactions followed by hybridisation to the specific probes. These included mecA/mecC, fusC, regulatory genes, recombinase genes, genes from ACME and heavy metal resistance loci as well as several genes of unknown function. Hybridisation patterns for published genome or SCC sequences were theoretically predicted. For validation of the microarray based assay and for stringent hybridisation protocol optimization, real hybridization experiments with fully sequenced reference strains were performed modifying protocols until yielded the results were in concordance to the theoretical predictions. Subsequently, 226 clinical isolates from two hospitals in the city of Dresden, Germany, were characterised in detail. Beside previously described types and subtypes, a wide variety of additional SCC types or subtypes and pseudoSCC elements were observed as well as numerous composite elements. Within the study collection, 61 different such elements have been identified. Since hybridisation cannot recognise the localisation of target genes, gene duplications or inversions, this is a rather conservative estimate. Interestingly, some widespread epidemic strains engulf distinct variants with different SCCmec subtypes. Notable examples are ST239-MRSA-III, CC5-, CC22-, CC30-, and CC45-MRSA-IV or CC398-MRSA-V. Conversely, identical SCC elements were observed in different strains with SCCmec IVa being spread among the highest number of Clonal Complexes. The proposed microarray can help to distinguish isolates that appear similar or identical by other typing methods and it can be used as high-throughput screening tool for the detection of putative new SCC types or variants that warrant further investigation and sequencing. The high degree of diversity of SCC elements even within so-called strains could be helpful for epidemiological typing. It also raises the question on scale and speed of the evolution of SCC elements. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review was conducted to gain insight into the efficacy of transmission of infectious agents to colony sentinels by soiled bedding transfer based on publications studying this subject in mice and rats. This information is essential to establish recommendations for the design of health monitoring programs which use sentinels to determine the microbiological status of laboratory animal colonies. Results: Fifteen original articles retrieved from PubMed, Embase, and CAB abstracts met the inclusion criteria. The design of the studies varied substantially per infectious agent with regard to dose of soiled bedding, exposure time, and sentinel strains used. Conclusion: With our conservative criteria for effectiveness, soiled bedding transfer appeared to be effective for MHV, MPV, TMEV, Helicobacter spp., and fur mite infections and ineffective for Sendai virus. For other infectious agents, such as MNV, EDIM, MVM, SDAV, Clostridium piliforme, and pinworms, too few data were available to be able to draw robust conclusions on the efficacy of soiled bedding transfer. Recommendation: The identified evidence only pertains to a portion of the infectious organisms included in the FELASA 2014 guidelines. As many animal facilities design their health monitoring program according to these recommendations, additional studies are warranted to draw comprehensive conclusions on the effective transmission of the infectious agents listed in these guidelines by soiled bedding transfer. [ABSTRACT FROM AUTHOR]

A photo-medical capsule that emits blue light for Helicobacter pylori treatment was described in this paper. The system consists of modules for pH sensing and measuring, light-emitting diode driver circuit, radio communication and microcontroller, and power management. The system can differentiate locations by monitoring the pH values of the gastrointestinal tract, and turn on and off the blue light according to the preset range of pH values. Our experimental tests show that the capsule can operate in the effective light therapy mode for more than 32 minutes and the wireless communication module can reliably transmit the measured pH value to a receiver located outside the body. [ABSTRACT FROM AUTHOR]

Antibiotic misuse in Romania has exacerbated the issue of antibiotic resistance, as patients often use antibiotics without proper medical consultation. This study aimed to assess the resistance of prevalent bacteria to different antibiotics. In this observational study conducted over six months, we analyzed 31 pediatric patients aged from 12 days to 13 years using the disk diffusion method. We identified 31 bacterial isolates, including 8 Gram-negative and 8 Gram-positive strains, with the most common being Pseudomonas aeruginosa, Escherichia coli, Streptococcus pneumoniae, methicillin-resistant Staphylococcus aureus, Streptococcus species, and Elizabethkingia meningoseptica. Our findings revealed that the most effective antibiotics were linezolid, ertapenem, and teicoplanin. In contrast, nearly all tested bacteria exhibited resistance to penicillin, followed by oxacillin and ampicillin. Resistance to cephalosporins varied with generation, showing higher resistance to lower-generation cephalosporins. The study highlights significant antibiotic resistance among common bacterial pathogens in Romanian pediatric patients, emphasizing the urgent need for controlled antibiotic use and alternative treatment strategies to combat this growing issue. Effective antibiotics such as linezolid and ertapenem offer potential solutions, whereas reliance on penicillin and lower-generation cephalosporins is increasingly futile. [ABSTRACT FROM AUTHOR]

Routine microbial inactivation procedures used in microbiology laboratories must be verified. In this study, the efficacy of surface disinfection using 70% Isopropanol, 0.45% Presept, and 1% Virkon was tested against 24 bacterial strains commonly handled in aquaculture microbiology laboratories. Isopropanol was ineffective against Nocardia asteroides NCIMB 1290, while Virkon was not effective against Aeromonas eucrenophila NCIMB 74 or Pediococcus acidilacti R52037. [ABSTRACT FROM AUTHOR]

Nucleases are enzymes that can degrade genomic DNA and RNA that decrease the accuracy of quantitative measures of those nucleic acids. Here, we study conventional heating, standard microwave irradiation, and Lyse-It, a microwave-based lysing technology, for the potential to fragment and inactivate DNA and RNA endonucleases. Lyse-It employs the use of highly focused microwave irradiation to the sample ultimately fragmenting and inactivating RNase A, RNase B, and DNase I. Nuclease size and fragmentation were determined visually and quantitatively by SDS polyacrylamide gel electrophoresis and the mini-gel Agilent 2100 Bioanalyzer system, with a weighted size calculated to depict the wide range of nuclease fragmentation. Enzyme activity assays were conducted, and the rates were calculated to determine the effect of various lysing conditions on each of the nucleases. The results shown in this paper clearly demonstrate that Lyse-It is a rapid and highly efficient way to degrade and inactivate nucleases so that nucleic acids can be retained for down-stream detection. [ABSTRACT FROM AUTHOR]

The survey described in this research paper aimed to investigate the economic and health impacts of birds on dairies. Birds are common pests on dairies, consuming and contaminating feed intended for cattle. As a result, dairy operators experience increased feed costs and increased pathogen and disease risk. We surveyed dairy operators attending the 2017 Washington Dairy Conference to examine the impact of birds on dairies in Washington State. Dairy operators reported feed losses valued at $55 per cow resulting in annual losses totaling $5.5 million in the Western region of the state and $9.2 million in the Eastern region of the state. Shooting was the most commonly used bird management method and European starlings (Sternus vulgaris) were the most frequently implicated species statewide. Bird abundance greater than 10,000 birds per day was associated with larger herd size and with self-reported presence of Johne’s disease and Salmonella. [ABSTRACT FROM AUTHOR]

Sigma factors are key proteins that mediate the recruitment of RNA polymerase to the promoter regions of genes, for the initiation of bacterial transcription. Multiple sigma factors in a bacterium selectively recognize their cognate promoter sequences, thereby inducing the expression of their own regulons. In this paper, we report the crystal structure of the σ4 domain of Bacillus subtilis SigW bound to the -35 promoter element. Purine-specific hydrogen bonds of the -35 promoter element with the recognition helix α9 of the σ4 domain occurs at three nucleotides of the consensus sequence (G-35, A-34, and G’-31 in G-35A-34A-33A-32C-31C-30T-29). The hydrogen bonds of the backbone with the α7 and α8 of the σ4 domain occurs at G’-30. These results elucidate the structural basis of the selective recognition of the promoter by SigW. In addition, comparison of SigW structures complexed with the -35 promoter element or with anti-sigma RsiW reveals that DNA recognition and anti-sigma factor binding of SigW are mutually exclusive. [ABSTRACT FROM AUTHOR]

As antimicrobial resistance increases, it is crucial to develop new treatment strategies to counter the emerging threat. In this paper, we consider combination therapies involving conventional antibiotics and debridement, coupled with a novel anti-adhesion therapy, and their use in the treatment of antimicrobial resistant burn wound infections. Our models predict that anti-adhesion–antibiotic–debridement combination therapies can eliminate a bacterial infection in cases where each treatment in isolation would fail. Antibiotics are assumed to have a bactericidal mode of action, killing bacteria, while debridement involves physically cleaning a wound (e.g. with a cloth); removing free bacteria. Anti-adhesion therapy can take a number of forms. Here we consider adhesion inhibitors consisting of polystyrene microbeads chemically coupled to a protein known as multivalent adhesion molecule 7, an adhesin which mediates the initial stages of attachment of many bacterial species to host cells. Adhesion inhibitors competitively inhibit bacteria from binding to host cells, thus rendering them susceptible to removal through debridement. An ordinary differential equation model is developed and the antibiotic-related parameters are fitted against new in vitro data gathered for the present study. The model is used to predict treatment outcomes and to suggest optimal treatment strategies. Our model predicts that anti-adhesion and antibiotic therapies will combine synergistically, producing a combined effect which is often greater than the sum of their individual effects, and that anti-adhesion–antibiotic–debridement combination therapy will be more effective than any of the treatment strategies used in isolation. Further, the use of inhibitors significantly reduces the minimum dose of antibiotics required to eliminate an infection, reducing the chances that bacteria will develop increased resistance. Lastly, we use our model to suggest treatment regimens capable of eliminating bacterial infections within clinically relevant timescales. [ABSTRACT FROM AUTHOR]

Image segmentation applied to medical image analysis is still a critical and important task. Although there exist several segmentation algorithms that have been widely studied in literature, these are subject to segmentation problems such as over- and under-segmentation as well as non-closed edges. In this paper, a simple method that combines well-known segmentation algorithms is presented. This method is applied to detect acid-fast bacilli (AFB) in bacilloscopies used to diagnose pulmonary tuberculosis (TB). This diagnosis can be performed through different tests, and the most used worldwide is smear microscopy because of its low cost and effectiveness. This diagnosis technique is based on the analysis and counting of the bacilli in the bacilloscopy observed under an optical microscope. The proposed method is used to segment the bacilli in digital images from bacilloscopies processed using Ziehl-Neelsen (ZN) staining. The proposed method is fast, has a low computational cost and good efficiency compared to other methods. The bacilli image segmentation is performed by image processing and analysis techniques, probability concepts and classifiers. In this work, a Bayesian classifier based on a Gaussian mixture model (GMM) is used. The segmentations' results are validated by using the Jaccard index, which indicates the efficiency of the classifier. [ABSTRACT FROM AUTHOR]

Streptococcus pneumonia is an important human pathogen that causes various severe diseases such as pneumonia, otitis and meningitis. Vaccination against S. pneumoniae is implemented in many developed countries. The presently used vaccines are safe, well tolerated but relatively expensive and require modification due to the immunological changes of the epidemic strains. This paper describes the development of a new pneumococcal vaccine candidate for immunization on mucosal surfaces. For this purpose the antigens of chimeric protein PSPF, previously suggested for an injectable S. pneumoniae vaccine, were expressed on the surface of the live probiotic strain Enterococcus faecium L3. Experiments on laboratory mice vaccinated with live bacteria demonstrated the appearance of the specific IgA and IgG which provide protection against the lethal S. pneumoniae infection. [ABSTRACT FROM AUTHOR]