Pre-Absorbed Immunoproteomics: A Novel Method for the Detection of Streptococcus suis Surface Proteins

Streptococcus suis serotype 2 (SS2) is a zoonotic pathogen that can cause infections in pigs and humans. Bacterial surface proteins are often investigated as potential vaccine candidates and biomarkers of virulence. In this study, a novel method for identifying bacterial surface proteins is presented, which combines immunoproteomic and immunoserologic techniques. Critical to the success of this new method is an improved procedure for generating two-dimensional electrophoresis gel profiles of S. suis proteins. The S. suis surface proteins identified in this study include muramidase-released protein precursor (MRP) and an ABC transporter protein, while MRP is thought to be one of the main virulence factors in SS2 located on the bacterial surface. Herein, we demonstrate that the ABC transporter protein can bind to HEp-2 cells, which strongly suggests that this protein is located on the bacterial cell surface and may be involved in pathogenesis. An immunofluorescence assay confirmed that the ABC transporter is localized to the bacterial outer surface. This new method may prove to be a useful tool for identifying surface proteins, and aid in the development of new vaccine subunits and disease diagnostics

Fitness of Escherichia coli during Urinary Tract Infection Requires Gluconeogenesis and the TCA Cycle

Microbial pathogenesis studies traditionally encompass dissection of virulence properties such as the bacterium's ability to elaborate toxins, adhere to and invade host cells, cause tissue damage, or otherwise disrupt normal host immune and cellular functions. In contrast, bacterial metabolism during infection has only been recently appreciated to contribute to persistence as much as their virulence properties. In this study, we used comparative proteomics to investigate the expression of uropathogenic Escherichia coli (UPEC) cytoplasmic proteins during growth in the urinary tract environment and systematic disruption of central metabolic pathways to better understand bacterial metabolism during infection. Using two-dimensional fluorescence difference in gel electrophoresis (2D-DIGE) and tandem mass spectrometry, it was found that UPEC differentially expresses 84 cytoplasmic proteins between growth in LB medium and growth in human urine (P<0.005). Proteins induced during growth in urine included those involved in the import of short peptides and enzymes required for the transport and catabolism of sialic acid, gluconate, and the pentose sugars xylose and arabinose. Proteins required for the biosynthesis of arginine and serine along with the enzyme agmatinase that is used to produce the polyamine putrescine were also up-regulated in urine. To complement these data, we constructed mutants in these genes and created mutants defective in each central metabolic pathway and tested the relative fitness of these UPEC mutants in vivo in an infection model. Import of peptides, gluconeogenesis, and the tricarboxylic acid cycle are required for E. coli fitness during urinary tract infection while glycolysis, both the non-oxidative and oxidative branches of the pentose phosphate pathway, and the Entner-Doudoroff pathway were dispensable in vivo. These findings suggest that peptides and amino acids are the primary carbon source for E. coli during infection of the urinary tract. Because anaplerosis, or using central pathways to replenish metabolic intermediates, is required for UPEC fitness in vivo, we propose that central metabolic pathways of bacteria could be considered critical components of virulence for pathogenic microbes

Cardiac remodeling indicators in adolescent athletes

Objective: The idea that different sports and physical training type results in different cardiac adaptations has been widely accepted. However, this remodelling process among different sport modalities is still not fully understood. Thus, the current study aims to investigate the heart morphology variation associated with a set of different modalities characterized by distinct models of preparation and different methods and demands of training and completion. Method: The sample comprises 42 basketball players, 73 roller hockey players, 28 judo athletes and 21 swimmers. Anthropometry was assessed by a single and experienced anthropometrist and the same technician performed the echocardiographic exams. Analysis of variance was used to study age, body size and echocardiograph parameters as well as different sport athlete’s comparison. Results: Basketball players are taller (F=23.448; p<0.001; ES-r=0.553), heavier (F=6.702; p<0.001; ES-r=0.334) and have a greater body surface area (F=11.896; p<0.001; ES-r=0.427). Basketball and hockey players have larger left auricle diameters compared with judo athletes (F=3.865; p=0.011; ES-r=0.316). Interventricular end-diastolic septal thickness (F=7.287; p<0.001; ES-r=0.347) and left ventricular posterior wall thickness (F=8.038; p<0.001; ES-r=0.362) of the judokas are smaller compared to the mean values of other sports participants. In addition, relative left parietal ventricular wall thickness is lower among swimmers compared with judokas (F=4.127; p=0.008; ES-r=0.268). Conclusion: The major contributors to changes in heart morphology are for the most part associated with sport-specific training and competition and the specific dynamics and adaptive mechanisms imposed by each sport.Objetivo: Os efeitos decorrentes da prática de diferentes modalidades desportivas resultam em padrões divergentes de adaptação cardíaca. A presente pesquisa procura estudar a variação da morfologia do coração associada a um conjunto de modalidades desportivas distintas quanto à natureza do esforço e aos modelos de preparação, incluindo metodologias de treino e sistemas de competição. Método: Foram estudados 42 basquetebolistas, 73 hoquistas, 28 judocas e 21 nadadores. A antropometria foi avaliada por um único e experiente antropometrista e os exames ecocardiográficos foram realizados pelo mesmo operador. Recorreu-se à análise da variância para estudar a variação associada a idade, medidas de tamanho corporal e parâmetros ecocardiográficos, bem como para a comparação entre os atletas de diferentes modalidades desportivas. Resultados: Os basquetebolistas são os atletas mais altos (F=23,448; p<0,001; ES-r=0,553), mais pesados (F=6,702; p<0,001; ES-r=0,334), com maior superfície corporal (F=11,896; p<0,001; ES-r=0,427) e, com os hoquistas, apresentam um diâmetro da aurícula esquerda superior ao dos judocas (F=3,865; p=0,011; ES-r=0,316). A espessura telediastólica do septo interventricular (F=7,287; p<0,001; ES-r=0,347) e da parede posterior do ventrículo esquerdo (F=8,038; p<0,001; ES-r=0,362) dos judocas é inferior à dos outros atletas, mesmo quando controlado para o tamanho corporal. Os nadadores apresentam uma espessura parietal relativa do ventrículo esquerdo superior à dos judocas (F=4,127; p=0,008; ES-r=0,268). Conclusão: As diferentes fontes de variação da morfologia cardíaca prendem-se com as dinâmicas do processo de treino, competição e correspondentemente com os mecanismos adaptativos, sobrepondo-se ao processo de formação desportiva a longo prazo

Prevalencia de infección por coronavirus SARS-CoV-2 en pacientes y profesionales de un hospital de media y larga estancia en España

Background and goals: The aim of the study is to know the prevalence of SARS-CoV-2 infection in patients and professional staff of a medium or long-stay hospital during the peak period of the pandemic in Spain, spring 2020. Material and methods: At the end of February 2020, we developed at the hospital a strategy to diagnose the SARS-CoV-2 infection consisting of complementing the realization of PCR tests at real time with a quick technique of lateral flow immunochromatography to detect IgG and IgM antibodies against the virus. We also developed a protocol to realize those diagnostic tests and considered an infection (current or past) a positive result in any of the above tests. We included 524 participants in the study (230 patients and 294 hospital staff), and divided them into hospital patients and Hemodialysis outpatients. Furthermore, we divided the hospital staff into healthcare and non-healthcare staff. The documented period was from March, 20th to April, 21st, 2020. Results: 26 out of 230 patients tested positive in any of the diagnostic techniques (PCR, antibodies IgG, IgM) with a 11.30% prevalence. According to patients groups, we got a 14.38% prevalence in hospital patients vs. 5.95% in outpatients, with a significantly higher risk in admitted patients after adjustment for age and gender (OR=3, 309, 95%CI: 1, 154-9, 495). 24 out of 294 hospital staff tested positive in any of the diagnostic techniques, with a 8.16% prevalence. According to the groups, we got a 8.91% prevalence in healthcare staff vs. 4.26% in non-healthcare staff. Thus, we do not see any statistically significant differences between hospital staff and patients as far as prevalence is concerned (P=0, 391), (OR=2, 200, 95%CI: 0, 500-9, 689). Conclusions: The result of the study was a quite low prevalence rate of SARS-CoV-2 infection, in both patients and hospital staff, being the hospital patients’ prevalence rate higher than the outpatients’, and the healthcare staff higher than the non-healthcare''s. Combining PCR tests (gold standard) with antibodies tests proved useful as a diagnostic strategy