245 research outputs found
Culture-dependent and sequencing methods revealed the absence of a bacterial community residing in the urine of healthy cats
A growing number of studies suggest that the lower urinary tract of humans and dogs can harbor a urinary microbiota. Nevertheless, a certain concern has developed that the microbiota reported could be due to unaccounted contamination, especially in low-biomass samples. The aim of this study was to investigate the bacterial community which populates the urine of healthy cats using two approaches: a culture-dependent approach which consisted of the expanded quantitative urine culture (EQUC) techniques capable of identifying live bacteria not growing in standard urine cultures, and a culture-independent approach which consisted of 16S ribosomal RNA next generation sequencing (16S rRNA NGS) capable of identifying bacterial DNA and exploring microbial diversity with high resolution. To avoid confounding factors of possible bacterial contamination, the urine was sampled using ultrasound-guided cystocentesis, and several sample controls and negative controls were analyzed. The urine sampled from the 10 cats included in the study showed no bacterial growth in the EQUC procedure. Although several reads were successfully originated using 16S rRNA NGS, a comparable pattern was observed between urine samples and the negative control, and no taxa were statistically accepted as non-contaminant. Taken together, the results obtained allowed stating that no viable bacteria were present in the urine of healthy cats without lower urinary tract disease and urinary tract infections, and that the bacterial DNA detected was of contaminant origin
Sex and N-terminal pro B-type natriuretic peptide: The potential mediating role of iron biomarkers.
BACKGROUND
Levels of N-terminal pro B-type natriuretic peptide (NT-proBNP), a marker of heart failure and cardiovascular risk, are generally higher in women than men. We explored whether iron biomarkers mediate sex differences in NT-proBNP levels.
METHODS
We included 5,343 community-dwelling individuals from the Prevention of Renal and Vascular Endstage Disease study. With linear regression analyses, we investigated the association of sex and iron biomarkers with NT-proBNP levels, independent of adjustment for potential confounders. The assessed iron biomarkers included ferritin, transferrin saturation (TSAT), hepcidin, and soluble transferrin receptor (sTfR). Next, we performed mediation analyses to investigate to which extent iron biomarkers influence the association between sex and NT-proBNP.
RESULTS
Of the included 5,343 participants, the mean standard deviation age was 52.2 ± 11.6 years and 52% were females. After adjustment for potential confounders, women compared to men, had higher NT-proBNP (β = 0.31; 95%CI = 0.29, 0.34), but lower ferritin (β = -0.37; 95%CI = -0.39, -0.35), hepcidin (β = -0.22, 95%CI = -0.24, -0.20), and TSAT (β = -0.07, 95% CI = -0.08, -0.06). Lower ferritin (β = -0.05, 95%CI = -0.08, -0.02), lower hepcidin (β = -0.04, 95%CI = -0.07, -0.006), and higher TSAT (β = 0.07; 95%CI = 0.01, 0.13) were associated with higher NT-proBNP. In mediation analyses, ferritin and hepcidin explained 6.5 and 3.1% of the association between sex and NT-proBNP, respectively, while TSAT minimally suppressed (1.9%) this association.
CONCLUSION
Our findings suggest that iron biomarkers marginally explain sex differences in levels of NT-proBNP. Future studies are needed to explore causality and potential mechanisms underlying these pathways
Thyroid function and risk of all-cause and cardiovascular mortality:a prospective population-based cohort study
PURPOSE
Although thyroid hormones are irrefutably implicated in cardiovascular physiology, the impact of within-reference range variations of thyroid function on cardiovascular disease (CVD) remains unclear. Elucidating this is important, since it could foster preventive treatment and reduce global CVD burden. We therefore investigated the impact of within-reference range variations of thyroid function on all-cause and cardiovascular mortality.
METHODS
We included community-dwelling individuals aged 28-75 years from a prospective cohort study, without known use of thyroid-affecting therapy and with thyrotropin within reference range. Associations of thyroid function with mortality were quantified using Cox models and adjusted for sociodemographic and cardiovascular risk factors.
RESULTS
Mean (SD) age of the 6,054 participants (52.0% male) was 53.3 (12.0) years. During 47,594 person-years of follow-up, we observed 380 deaths from all causes and 103 from CVDs. Although higher thyrotropin was not associated with all-cause mortality (adjusted HR 1.02, 95% CI 0.92-1.14), point estimates for cardiovascular mortality diverged toward increased risk in younger (<72 years) participants (1.31, 1.00-1.72) and decreased risk in elderly (≥72 years) (0.77, 0.56-1.06). Higher free thyroxine (FT4) was associated with all-cause mortality (1.18, 1.07-1.30) and with cardiovascular mortality only in elderly (1.61, 1.19-2.18), but not in younger participants (1.03, 0.78-1.34). Higher free triiodothyronine (FT3) was associated with all-cause mortality in females only (1.18, 1.02-1.35). FT3 was not associated with cardiovascular mortality (0.91, 0.70-1.18).
CONCLUSIONS
Community-dwelling elderly individuals with high-normal thyroid function are at increased risk of all-cause and cardiovascular mortality, reinforcing the need of redefining the current reference ranges of thyroid function
Clinical profiles of patients colonized or infected with extended-spectrum beta-lactamase producing Enterobacteriaceae isolates: a 20 month retrospective study at a Belgian University Hospital
<p>Abstract</p> <p>Background</p> <p>Description of the clinical pictures of patients colonized or infected by ESBL-producing <it>Enterobacteriaceae </it>isolates and admitted to hospital are rather scarce in Europe. However, a better delineation of the clinical patterns associated with the carriage of ESBL-producing isolates may allow healthcare providers to identify more rapidly at risk patients. This matter is of particular concern because of the growing proportion of ESBL-producing <it>Enterobacteriaceae </it>species isolates worldwide.</p> <p>Methods</p> <p>We undertook a descriptive analysis of 114 consecutive patients in whom ESBL-producing <it>Enterobacteriaceae </it>isolates were collected from clinical specimens over a 20-month period. Clinical data were obtained through retrospective analysis of medical record charts. Microbiological cultures were carried out by standard laboratory methods.</p> <p>Results</p> <p>The proportion of ESBL-producing <it>Enterobacteriaceae </it>strains after exclusion of duplicate isolates was 4.5% and the incidence rate was 4.3 cases/1000 patients admitted. Healthcare-associated acquisition was important (n = 104) while community-acquisition was less frequently found (n = 10). Among the former group, two-thirds of the patients were aged over 65 years and 24% of these were living in nursing homes. Sixty-eight (65%) of the patients with healthcare-associated ESBL, were considered clinically infected. In this group, the number and severity of co-morbidities was high, particularly including diabetes mellitus and chronic renal insufficiency. Other known risk factors for ESBL colonization or infection such as prior antibiotic exposure, urinary catheter or previous hospitalisation were also often found. The four main diagnostic categories were: urinary tract infections, lower respiratory tract infections, septicaemia and intra-abdominal infections. For hospitalized patients, the median hospital length of stay was 23 days and the average mortality rate during hospitalization was 13% (Confidence Interval 95%: 7-19). <it>Escherichia coli</it>, by far, accounted as the most common ESBL-producing <it>Enterobacteriaceae </it>species (77/114; [68%]) while CTX-M-1 group was by far the most prevalent ESBL enzyme (n = 56).</p> <p>Conclusion</p> <p>In this retrospective study, the clinical profiles of patients carrying healthcare-associated ESBL-producing <it>Enterobacteriacae </it>is characterized by a high prevalence rate of several major co-morbidities and potential known risk factors. Both, the length of hospital stay and overall hospital mortality rates were particularly high. A prospective case-control matched study should be designed and performed in order to control for possible inclusion bias.</p
High prevalence of fecal carriage of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae in a pediatric unit in Madagascar
<p>Abstract</p> <p>Background</p> <p>Extended-spectrum β-lactamase (ESBL)-producing <it>Enterobacteriaceae </it>have spread worldwide but there are few reports on carriage in hospitals in low-income countries. ESBL-producing <it>Enterobacteriaceae </it>(ESBL-PE) have been increasingly isolated from nosocomial infections in Antananarivo, Madagascar.</p> <p>Methods</p> <p>we conducted a prevalence survey in a pediatric unit from March to April 2008 Patient rectal swabs were sampled on the first and the last day of hospitalization. Medical staff and environment were also sampled. Rectal and environmental swabs were immediately plated onto Drigalski agar supplemented with 3 mg/liter of ceftriaxon.</p> <p>Results</p> <p>Fecal carriage was detected in 21.2% of 244 infants on admission and 57.1% of 154 on discharge, after more than 48 hours of hospitalization (p < 0.001). The species most frequently detected on admission were <it>Escherichia coli and Klebsiella pneumoniae </it>(36.9%), whereas, on discharge, <it>K. pneumoniae </it>was the species most frequently detected (52.7%). ESBL-associated resistances were related to trimethoprim-sulfamethoxazole (91.3%), gentamicin (76.1%), ciprofloxacin (50.0%), but not to amikacin and imipenem. The increased prevalence of carriage during hospitalization was related to standard antimicrobial therapy.</p> <p>Conclusion</p> <p>The significant emergence of multidrug-resistant enteric pathogens in Malagasy hospitals poses a serious health threat requiring the implementation of surveillance and control measures for nosocomial infections.</p
p73: A Multifunctional Protein in Neurobiology
p73, a transcription factor of the p53 family, plays a key role in many biological processes including neuronal development. Indeed, mice deficient for both TAp73 and ΔNp73 isoforms display neuronal pathologies, including hydrocephalus and hippocampal dysgenesis, with defects in the CA1-CA3 pyramidal cell layers and the dentate gyrus. TAp73 expression increases in parallel with neuronal differentiation and its ectopic expression induces neurite outgrowth and expression of neuronal markers in neuroblastoma cell lines and neural stem cells, suggesting that it has a pro-differentiation role. In contrast, ΔNp73 shows a survival function in mature cortical neurons as selective ΔNp73 null mice have reduced cortical thickness. Recent evidence has also suggested that p73 isoforms are deregulated in neurodegenerative pathologies such as Alzheimer’s disease, with abnormal tau phosphorylation. Thus, in addition to its increasingly accepted contribution to tumorigenesis, the p73 subfamily also plays a role in neuronal development and neurodegeneration
The HIV-1 Nef protein binds argonaute-2 and functions as a viral suppressor of RNA interference
The HIV-1 accessory protein Nef is an important virulence factor. It associates with cellular membranes and modulates the endocytic machinery and signaling pathways. Nef also increases the proliferation of multivesicular bodies (MVBs), which are sites for virus assembly and budding in macrophages. The RNA interference (RNAi) pathway proteins Ago2 and GW182 localize to MVBs, suggesting these to be sites for assembly and turnover of the miRNA-induced silencing complex (miRISC). While RNAi affects HIV replication, it is not clear if the virus encodes a suppressor activity to overcome this innate host response. Here we show that Nef colocalizes with MVBs and binds Ago2 through two highly conserved Glycine-Tryptophan (GW) motifs, mutations in which abolish Nef binding to Ago2 and reduce virus yield and infectivity. Nef also inhibits the slicing activity of Ago2 and disturbs the sorting of GW182 into exosomes resulting in the suppression of miRNA-induced silencing. Thus, besides its other activities, the HIV-1 Nef protein is also proposed to function as a viral suppressor of RNAi (VSR)
Oral fosfomycin for treatment of urinary tract infection: a retrospective cohort study
Microbial community structure elucidates performance of Glyceria maxima plant microbial fuel cell
The plant microbial fuel cell (PMFC) is a technology in which living plant roots provide electron donor, via rhizodeposition, to a mixed microbial community to generate electricity in a microbial fuel cell. Analysis and localisation of the microbial community is necessary for gaining insight into the competition for electron donor in a PMFC. This paper characterises the anode–rhizosphere bacterial community of a Glyceria maxima (reed mannagrass) PMFC. Electrochemically active bacteria (EAB) were located on the root surfaces, but they were more abundant colonising the graphite granular electrode. Anaerobic cellulolytic bacteria dominated the area where most of the EAB were found, indicating that the current was probably generated via the hydrolysis of cellulose. Due to the presence of oxygen and nitrate, short-chain fatty acid-utilising denitrifiers were the major competitors for the electron donor. Acetate-utilising methanogens played a minor role in the competition for electron donor, probably due to the availability of graphite granules as electron acceptors
Management of multidrug resistant Gram-negative bacilli infections in solid organ transplant recipients: SET/GESITRA-SEIMC/REIPI recommendations
Solid organ transplant (SOT) recipients are especially at risk of developing infections by multidrug resistant (MDR) Gram-negative bacilli (GNB), as they are frequently exposed to antibiotics and the healthcare setting, and are regulary subject to invasive procedures. Nevertheless, no recommendations concerning prevention and treatment are available. A panel of experts revised the available evidence; this document summarizes their recommendations: (1) it is important to characterize the isolate´s phenotypic and genotypic resistance profile; (2) overall, donor colonization should not constitute a contraindication to transplantation, although active infected kidney and lung grafts should be avoided; (3) recipient colonization is associated with an increased risk of infection, but is not a contraindication to transplantation; (4) different surgical prophylaxis regimens are not recommended for patients colonized with carbapenem-resistant GNB; (5) timely detection of carriers, contact isolation precautions, hand hygiene compliance and antibiotic control policies are important preventive measures; (6) there is not sufficient data to recommend intestinal decolonization; (7) colonized lung transplant recipients could benefit from prophylactic inhaled antibiotics, specially for Pseudomonas aeruginosa; (8) colonized SOT recipients should receive an empirical treatment which includes active antibiotics, and directed therapy should be adjusted according to susceptibility study results and the severity of the infection.J.T.S. holds a research contract from the Fundación para la Formación e Investigación de los Profesionales de la Salud de Extremadura (FundeSalud), Instituto de Salud Carlos III. M.F.R. holds a clinical research contract “Juan Rodés” (JR14/00036) from the Spanish Ministry of Economy and Competitiveness, Instituto de Salud Carlos III
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