128 research outputs found
Comparison of efflux pump involvement in antibiotic resistance among pseudomonas aeruginosa isolates of burn and non-burn patients
Background: Pseudomonas aeruginosa is an important cause of hospital-acquired infections that can create serious problem for patients and physicians. Many factors are associated with the antibiotic resistance of P. aeruginosa, such as efflux pumps. Objectives: The aim of this study was the phenotypic and molecular detection of efflux pumps in our clinical P. aeruginosa isolates in a comparison between burn and non-burn specimens. Materials and Methods: In this study, clinical strains of P. aeruginosa were collected from burn and non-burn specimens from April-July 2013. Antibiotic susceptibility testing of the isolates was performed after biochemical and molecular identification. The minimum inhibitory concentration (MIC) of imipenem, cefepime, gentamycin, and ciprofloxacin, with and without carbonyl cyanide 3-chlorophenylhydrazone (CCCP), was determined for phenotypic detection of efflux pumps. Results: Our results confirmed 203 and 60 P. aeruginosa isolates from burn and non-burn specimens, respectively. The most antibiotic resistance was observed against tobramycin in both group of specimens, and no resistance was seen to colistin. Phenotypic detection of efflux pumps was determined to correlate to a > 4-fold decrease in the MICs of the tested antibiotics with CCCP compared to without CCCP in 57 strains. Conclusions: High-level antibiotic resistance can occur as a result of multidrug efflux pumps combined with other mechanisms of resistance. However, the association between over-expression of these genes and highly resistant clinical isolates cannot be ignored. � 2016, Pediartric Infections Research Center
Simplifying sensemaking: concept, process, strengths, shortcomings, and ways forward for information systems in contemporary business environments
Sensemaking is a popular and useful organizational behaviour concept that is gaining visibility in the field of information systems. However, it remains relatively unknown compared to more established information systems concepts like technology acceptance and resistance. To enhance and propel greater use of sensemaking in information systems, this article offers a systematic explanation of sensemaking, specifically focusing on its concept, process, strengths, and shortcomings, as well as discussing ways forward for information systems in contemporary business environments
A simple and rapid approach for screening of SARS-coronavirus genotypes: an evaluation study
BACKGROUND: The Severe Acute Respiratory Syndrome (SARS) was a newly emerged infectious disease which caused a global epidemic in 2002–2003. Sequence analysis of SARS-coronavirus isolates revealed that specific genotypes predominated at different periods of the epidemic. This information can be used as a footprint for tracing the epidemiology of infections and monitor viral evolution. However, direct sequencing analysis of a large number of clinical samples is cumbersome and time consuming. We present here a simple and rapid assay for the screening of SARS-coronavirus genotypes based on the use of fluorogenic oligonucleotide probes for allelic discrimination. METHODS: Thirty SARS patients were recruited. Allelic discrimination assays were developed based on the use of fluorogenic oligonucleotide probes (TaqMan). Genotyping of the SARS-coronavirus isolates obtained from these patients were carried out by the allelic discrimination assays and confirmed by direct sequencing. RESULTS: Genotyping based on the allelic discrimination assays were fully concordant with direct sequencing. All of the 30 SARS-coronavirus genotypes studied were characteristic of genotypes previously documented to be associated with the latter part of the epidemic. Seven of the isolates contained a previously reported major deletion but in patients not epidemiologically related to the previously studied cohort. CONCLUSION: We have developed a simple and accurate method for the characterization and screening of SARS-coronavirus genotypes. It is a promising tool for the study of epidemiological relationships between documented cases during an outbreak
Genital herpes evaluation by quantitative TaqMan PCR: correlating single detection and quantity of HSV-2 DNA in cervicovaginal lavage fluids with cross-sectional and longitudinal clinical data
Abstract Objective To evaluate the utility of a single quantitative PCR (qPCR) measurement of HSV (HSV-1&2) DNA in cervicovaginal lavage (CVL) specimens collected from women with predominantly chronic HSV-2 infection in assessing genital HSV shedding and the clinical course of genital herpes (GH) within a cohort with semiannual schedule of follow up and collection of specimens. Methods Two previously described methods used for detection of HSV DNA in mucocutaneous swab samples were adapted for quantification of HSV DNA in CVLs. Single CVL specimens from 509 women were tested. Presence and quantity of CVL HSV DNA were explored in relation to observed cross-sectional and longitudinal clinical data. Results The PCR assay was sensitive and reproducible with a limit of quantification of ~50 copies per milliliter of CVL. Overall, 7% of the samples were positive for HSV-2 DNA with median log10 HSV-2 DNA copy number of 3.9 (IQR: 2.6-5.7). No HSV-1 was detected. Presence and quantity of HSV-2 DNA in CVL directly correlated with the clinical signs and symptoms of presence of active symptomatic disease with frequent recurrences. Conclusion Single qPCR measurement of HSV DNA in CVL fluids of women with chronic HSV-2 infection provided useful information for assessing GH in the setting of infrequent sampling of specimens. Observed positive correlation of the presence and quantity of HSV-2 DNA with the presence of active and more severe course of HSV-2 infection may have clinical significance in the evaluation and management of HSV-2 infected patients
Role of Fas/FasL in regulation of inflammation in vaginal tissue during HSV-2 infection
To assess the role of Fas in lesion development during genital HSV-2 infection, we used a well-established HSV-2 murine model applied to MRL-Faslpr/J (Fas−/−) and C3-Faslgld/J (FasL−/−) C57BL6 mice. In vitro infection of murine keratinocytes and epithelial cells was used to clarify molecular details of HSV-2 infection. Despite upregulation of Fas and FasL, HSV-2-infected keratinocytes and epithelial cells showed a moderate level of apoptosis due to upregulated expression of the anti-apoptotic factors Bcl-2, Akt kinase and NF-κB. Inflammatory lesions within the HSV-2-infected epithelium of C57BL6 mice consisted of infected cells upregulating Fas, FasL and Bcl-2, uninfected cells upregulating Fas and neutrophils expressing both Fas and FasL. Apoptosis was detected in HSV-2-infected cells and to even higher extent in non-infected cells surrounding HSV-2 infection sites. HSV-2 infection of Fas- and FasL-deficient mice led to increased apoptosis and stronger recruitment of neutrophils within the infection sites. We conclude that the Fas pathway participates in regulation of inflammatory response in the vaginal epithelium at the initial stage of HSV-2 infection
Factors affecting study efficiency and item non-response in health surveys in developing countries: the Jamaica national healthy lifestyle survey
BACKGROUND: Health surveys provide important information on the burden and secular trends of risk factors and disease. Several factors including survey and item non-response can affect data quality. There are few reports on efficiency, validity and the impact of item non-response, from developing countries. This report examines factors associated with item non-response and study efficiency in a national health survey in a developing Caribbean island. METHODS: A national sample of participants aged 15–74 years was selected in a multi-stage sampling design accounting for 4 health regions and 14 parishes using enumeration districts as primary sampling units. Means and proportions of the variables of interest were compared between various categories. Non-response was defined as failure to provide an analyzable response. Linear and logistic regression models accounting for sample design and post-stratification weighting were used to identify independent correlates of recruitment efficiency and item non-response. RESULTS: We recruited 2012 15–74 year-olds (66.2% females) at a response rate of 87.6% with significant variation between regions (80.9% to 97.6%; p < 0.0001). Females outnumbered males in all parishes. The majority of subjects were recruited in a single visit, 39.1% required multiple visits varying significantly by region (27.0% to 49.8% [p < 0.0001]). Average interview time was 44.3 minutes with no variation between health regions, urban-rural residence, educational level, gender and SES; but increased significantly with older age category from 42.9 minutes in the youngest to 46.0 minutes in the oldest age category. Between 15.8% and 26.8% of persons did not provide responses for the number of sexual partners in the last year. Women and urban residents provided less data than their counterparts. Highest item non-response related to income at 30% with no gender difference but independently related to educational level, employment status, age group and health region. Characteristics of non-responders vary with types of questions. CONCLUSION: Informative health surveys are possible in developing countries. While survey response rates may be satisfactory, item non-response was high in respect of income and sexual practice. In contrast to developed countries, non-response to questions on income is higher and has different correlates. These findings can inform future surveys
Broad environmental tolerance of native root- nodule bacteria of Biserrula pelecinus indicate potential for soil fertility restoration
Background: Biserrula pelecinus is an annual legume native to the Mediterranean basin, found in pastureland, alone or in association with other legumes (Leguminosae) and grasses (Poaceae). It has been used in revegetation programmes of mining wastes showing phytoremediation potentials and thus becoming potentially highly attractive for plant ecology and restoration management of natural ecosystems.
Aims: To characterise native root-nodule bacteria isolated from B. pelecinus from the Iberian Peninsula, and to select suitable N fixers for field-application and soil rehabilitation.
Methods: Strains were isolated and molecularly identified by 16S rRNA amplification and sequencing. Strains were phenotypically characterised in different abiotic conditions (acidity, salinity and heavy metals) and tested for their ability to fix atmospheric N2. The most suitable N fixers were applied in greenhouse experiments with B. pelecinus under different fertilization levels to assess their tolerance to fertilized and polluted soils, commonly encountered in restoration projects. Results: B. pelecinus root-nodule isolates tolerated pH from 4.5 to 9.5 grew in saline conditions (2.5% of NaCl), and tolerated 50 μM of Al3+ and Mn2+. Three isolates efficient in N2 fixation, relative to the reference Mesorhizobium strain, were considered excellent candidates for the amelioration of nutrient poor sites.
Conclusions: These results provide valuable information for the potential use in soil restoration of B. pelecinus in a wide- range of conditions, exploiting the natural variability of its root-nodule bacteria
Electrochemically synthesized polymers in molecular imprinting for chemical sensing
This critical review describes a class of polymers prepared by electrochemical polymerization that employs the concept of molecular imprinting for chemical sensing. The principal focus is on both conducting and nonconducting polymers prepared by electropolymerization of electroactive functional monomers, such as pristine and derivatized pyrrole, aminophenylboronic acid, thiophene, porphyrin, aniline, phenylenediamine, phenol, and thiophenol. A critical evaluation of the literature on electrosynthesized molecularly imprinted polymers (MIPs) applied as recognition elements of chemical sensors is presented. The aim of this review is to highlight recent achievements in analytical applications of these MIPs, including present strategies of determination of different analytes as well as identification and solutions for problems encountered
Seed priming and sulfur effects on soybean cell membrane stability and yield in saline soil
Tannic Acid Modified Silver Nanoparticles Show Antiviral Activity in Herpes Simplex Virus Type 2 Infection
The interaction between silver nanoparticles and herpesviruses is attracting great interest due to their antiviral activity and possibility to use as microbicides for oral and anogenital herpes. In this work, we demonstrate that tannic acid modified silver nanoparticles sized 13 nm, 33 nm and 46 nm are capable of reducing HSV-2 infectivity both in vitro and in vivo. The antiviral activity of tannic acid modified silver nanoparticles was size-related, required direct interaction and blocked virus attachment, penetration and further spread. All tested tannic acid modified silver nanoparticles reduced both infection and inflammatory reaction in the mouse model of HSV-2 infection when used at infection or for a post-infection treatment. Smaller-sized nanoparticles induced production of cytokines and chemokines important for anti-viral response. The corresponding control buffers with tannic acid showed inferior antiviral effects in vitro and were ineffective in blocking in vivo infection. Our results show that tannic acid modified silver nanoparticles are good candidates for microbicides used in treatment of herpesvirus infections.This work was supported by the Polish National Science Centre grant No. 2011/03/B/NZ6/04878 (for MK) and Centre for Preclinical Research and
Technology (CePT) Project No. POIG.02.02.00-14-024/08-0 (for MG and MD). The funders had no role in study design, data collection and analysis, decision to
publish, or preparation of the manuscrip
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