119 research outputs found
Chemical composition and antimicrobial activities of the essential oil from Myrtus communis leaves
Abstract: Nosocomial pathogens are associated with increased hospital stay lengths and mortality
rates. Increasing resistance to antibiotics makes the treatment of these infections more difficult. Novel
antimicrobial compounds derived from natural sources may be useful for addressing antiobiotic resistance.
The objective of this study is to determine the chemical composition and antimicrobial activities of essential
oils from Myrtus communis L. (Myrtaceae) leaves against pathogens causing nosocomial infections. The
chemical composition of essential oil from M. communis leaves was analysed by gas chromatography-mass
spectrometry (GC-MS). The antimicrobial activity of the essential oil against bacteria and fungi was evaluated
by broth micro-dilution as per the Clinical and Laboratory Standards Institute (CLSI) methods. GC-MS analysis
revealed that the major constituents of the essential oil were α-pinene (39.2 %), 1,8-cineole (22.0 %), and
linalool (18.4 %). The essential oil exhibited antimicrobial activity against all Gram positive and Gram negative
bacteria with MICs in the range of 0.5-32 μL/mL and 8-64 μL/mL, respectively. MICs for the tested
clinical and standard fungi were in the range of 0.03-16 μL/mL. The essential oil exhibited strong antibacterial
and antifungal activities against all the causative agents of nosocomial infections examined, particularly
against strains with antibiotic resistance. The essential oil from M. communis leaves is a potential source of
novel antimicrobial agents for the treatment of nosocomial infections
Evaluation of CAMP-Like Effect, Biofilm Formation, and Discrimination of Candida africana
Candida africana as a species recovered from female genital specimens is highly close to C. albicans. The present study was conducted to discriminate C. africana from presumptive vaginal C. albicans strains by molecular assay and evaluate their hemolysin activity, biofilm formation, and cohemolytic effect (CAMP) with vaginal bacterial flora. A total of 110 stock vaginal C. albicans isolates were examined by HWP1 gene amplification. Hemolysin activity and the ability of biofilm formation were evaluated by blood plate assay and visual detection methods, respectively. Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus agalactiae were used to evaluate the CAMP-like effects in Sabouraud blood agar media. Based on the size of the amplicons (941 bp), all isolates were identified as C. albicans. All samples were able to produce beta-hemolysin. Moreover, 69 out of 110 of the isolates (62.7%) were biofilm-positive, 54 out of 110 Candida isolates (49%) demonstrated cohemolytic effects with S. agalactiae, and 48 out of 110 showed this effect with S. aureus (43.6%). All isolates were CAMP-negative with S. epidermidis. We detected all isolates as Candida albicans and almost half of the isolates were CAMP-positive with S. aureus and S. agalactiae, suggesting that these bacteria increase the pathogenicity of Candida in vaginal candidiasis
Identification and antifungal activity profile of Candida species isolated from patients with pemphigus vulgaris with oral lesions
Pemphigus vulgaris is an autoimmune disease that mostly affects the mucosa and oral cavity. Candida species can invade the mucosal lesions of these patients and cause diseases. The aim of this study was to identify the fungal agents isolated from mucosal lesions and evaluate antifungal activity profile against the isolates. A total of 25 patients with pemphigus vulgaris with active oral lesions and 25 healthy people serving as a control group were included in this study. Identification of the fungal isolates was performed based on conventional methods and DNA sequence analysis of the internal transcribed spacer (ITS) rDNA gene region. The sequence results were deposited in the NCBI database using the Basic Local Alignment Search Tool. Antifungal activity of fluconazole, itraconazole, ketoconazole, posaconazole, econazole, and amphotericin B against the isolates were evaluated based on the CLSI M-44 A protocol. Oral candidiasis was detected in 20% of the patients. Candida species isolated from oral lesions of patients with pemphigus were identified as Candida albicans 22/25, Candida glabrata 2/25, and Candida dubliniensis 1/25. All of the isolates were sensitive to amphotericin and econazole, 96% to fluconazole and posaconazole, and 92% to ketoconazole and itraconazole. One patient showed a profile resistant to fluconazole, posaconazole, and ketoconazole, simultaneously. Ninety six percent of control group isolates were sensitive to six antifungals. Candida albicans was the most prevalent species isolated from oral lesions of patients with pemphigus vulgaris and the control group. Amphotericin B and econazole were the most effective antifungals against the isolates. </p
Chemical Composition, Antifungal and Antibiofilm Activities of the Essential Oil of <i>Mentha piperita</i> L.
Variations in quantity and quality of essential oil (EO) from the aerial parts of cultivated Mentha piperita were determined. The EO of air-dried sample was obtained by a hydrodistillation method and analyzed by a gas chromatography/mass spectrometry (GC/MS). The antifungal activity of the EO was investigated by broth microdilution methods as recommended by Clinical and Laboratory Standards Institute. A biofilm formation inhibition was measured by using an XTT reduction assay. Menthol (53.28%) was the major compound of the EO followed by Menthyl acetate (15.1%) and Menthofuran (11.18%). The EO exhibited strong antifungal activities against the examined fungi at concentrations ranging from 0.12 to 8.0 μL/mL. In addition, the EO inhibited the biofilm formation of Candida albicans and C. dubliniensis at concentrations up to 2 μL/mL. Considering the wide range of the antifungal activities of the examined EO, it might be potentially used in the management of fungal infections or in the extension of the shelf life of food products.</jats:p
Emergence of Terbinafine Resistant Trichophyton mentagrophytes in Iran, Harboring Mutations in the Squalene Epoxidase (SQLE) Gene
Introduction: Trichophyton mentagrophytes and T. interdigitale are important causative agents of superficial mycoses, demonstrating emergent antifungal drug resistance. We studied the antifungal susceptibility profiles in Iranian isolates of these two species.
Methods: A total of 96 T. interdigitale and 45 T. mentagrophytes isolates were subjected to molecular typing by ribosomal ITS region. Antifungal susceptibility profiles for terbinafine, griseofulvin, clotrimazole, efinaconazole, luliconazole, amorolfine and ciclopirox were obtained by CLSI broth microdilution method. The squalene epoxidase (SQLE) gene was subjected to sequencing for mutations, if any, in isolates exhibiting elevated MICs for terbinafine.
Results: Luliconazole and efinaconazole showed the lowest MIC values against T. mentagrophytes and T. interdigitale isolates. There were five isolates with terbinafine MICs >= 32 mu g/mL in our sample. They belonged to T. mentagrophytes type VIII and harbored two alternative SQLE gene sequence variants, leading to Phe397Leu and Ala448Thr or Leu393Ser and Ala448Thr substitutions in the enzyme. All terbinafine resistant strains could be inhibited by luliconazole and efinaconazole.
Conclusion: This study documented a step in the global spread of resistance mechanisms in T. mentagrophytes. However, treatment alternatives for resistant isolates were available.
Keywords:Trichophyton mentagrophytes; SQLE; terbinafine; antifungal drug resistance; Ira
Design, Synthesis, and Antifungal Activity of New <i>α</i>-Aminophosphonates
α-Aminophosphonates are bioisosteres of amino acids and have several pharmacological activities. These compounds have been synthesized by various routes from reaction between amine, aldehyde, and phosphite compounds. In order to synthesize α-aminophosphonates, catalytic effect of CuCl2 was compared with FeCl3. Also all designed structures as well as griseofulvin were docked into the active site of microtubule (1JFF), using Autodock program. The results showed that the reactions were carried out in the presence of CuCl2 in lower yields, and also the time of reaction was longer in comparison with FeCl3. The chemical structures of the new compounds were confirmed by spectral analyses. The compounds were investigated for antifungal activity against several fungi in comparison with griseofulvin. An indole-derived bis(α-aminophosphonates) with the best negative ΔG in docking study showed maximum antifungal activity against Microsporum canis, and other investigated compounds did not have a good antifungal activity.</jats:p
The effect of seating preferences of the medical students on educational achievement
Background: The seat selection and classroom dynamics may have mutual influence on the student performance and participation in both assigned and random seating arrangement. Purpose: The aim of the study was to understand the influence of seat selection on educational achievement. Methods: The seating positions of the medical students were recorded on an architectural plan during each class session and the means and standard deviations of the students’ locations were calculated in X and Y orientations. The locations of the students in the class were analyzed based on three architectural classifications: interactional zone, distance from the board, and access to the aisles. Final exam scores were used to measure the students’ educational achievement. Results: Our results demonstrate that there is a statistically significant relationship between the student's locations in the class and their attendance and educational achievements. Conclusion: Two factors may effect on educational achievement: student seating in the high interactional zone and minimal changes in seating location. Seating in the high interaction zone was directly associated with higher performance and inversely correlated with the percentage of absences. This observation is consistent with the view that students in the front of the classroom are likely more motivated and interact with the lecturer more than their classmates
Proteolytic activity and cooperative hemolytic effect of dermatophytes with different species of bacteria
The global, regional, and national burden of oesophageal cancer and its attributable risk factors in 195 countries and territories, 1990-2017: A systematic analysis for the global burden of disease study 2017
© 2020 The Author(s). Background Oesophageal cancer is a common and often fatal cancer that has two main histological subtypes: oesophageal squamous cell carcinoma and oesophageal adenocarcinoma. Updated statistics on the incidence and mortality of oesophageal cancer, and on the disability-adjusted life-years (DALYs) caused by the disease, can assist policy makers in allocating resources for prevention, treatment, and care of oesophageal cancer. We report the latest estimates of these statistics for 195 countries and territories between 1990 and 2017, by age, sex, and Socio-demographic Index (SDI), using data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD). Methods We used data from vital registration systems, vital registration-samples, verbal autopsy records, and cancer registries, combined with relevant modelling, to estimate the mortality, incidence, and burden of oesophageal cancer from 1990 to 2017. Mortality-to-incidence ratios (MIRs) were estimated and fed into a Cause of Death Ensemble model (CODEm) including risk factors. MIRs were used for mortality and non-fatal modelling. Estimates of DALYs attributable to the main risk factors of oesophageal cancer available in GBD were also calculated. The proportion of oesophageal squamous cell carcinoma to all oesophageal cancers was extracted by use of publicly available data, and its variation was examined against SDI, the Healthcare Access and Quality (HAQ) Index, and available risk factors in GBD that are specific for oesophageal squamous cell carcinoma (eg, unimproved water source and indoor air pollution) and for oesophageal adenocarcinoma (gastro-oesophageal reflux disease). Findings There were 473 000 (95% uncertainty interval [95% UI] 459 000-485 000) new cases of oesophageal cancer and 436 000 (425 000-448 000) deaths due to oesophageal cancer in 2017. Age-standardised incidence was 5.9 (5.7-6.1) per 100 000 population and age-standardised mortality was 5.5 (5.3-5.6) per 100 000. Oesophageal cancer caused 9.78 million (9.53-10.03) DALYs, with an age-standardised rate of 120 (117-123) per 100 000 population. Between 1990 and 2017, age-standardised incidence decreased by 22.0% (18.6-25.2), mortality decreased by 29.0% (25.8-32.0), and DALYs decreased by 33.4% (30.4-36.1) globally. However, as a result of population growth and ageing, the total number of new cases increased by 52.3% (45.9-58.9), from 310 000 (300 000-322 000) to 473 000 (459 000-485 000); the number of deaths increased by 40.0% (34.1-46.3), from 311 000 (301 000-323 000) to 436 000 (425 000-448 000); and total DALYs increased by 27.4% (22.1-33.1), from 7.68 million (7.42-7.97) to 9.78 million (9.53-10.03). At the national level, China had the highest number of incident cases (235 000 [223 000-246 000]), deaths (213 000 [203 000-223 000]), and DALYs (4.46 million [4.25-4.69]) in 2017. The highest national-level agestandardised incidence rates in 2017 were observed in Malawi (23.0 [19.4-26.5] per 100 000 population) and Mongolia (18.5 [16.4-20.8] per 100 000). In 2017, age-standardised incidence was 2.7 times higher, mortality 2.9 times higher, and DALYs 3.0 times higher in males than in females. In 2017, a substantial proportion of oesophageal cancer DALYs were attributable to known risk factors: tobacco smoking (39.0% [35.5-42.2]), alcohol consumption (33.8% [27.3-39.9]), high BMI (19.5% [6.3-36.0]), a diet low in fruits (19.1% [4.2-34.6]), and use of chewing tobacco (7.5% [5.2-9.6]). Countries with a low SDI and HAQ Index and high levels of indoor air pollution had a higher proportion of oesophageal squamous cell carcinoma to all oesophageal cancer cases than did countries with a high SDI and HAQ Index and with low levels of indoor air pollution. Interpretation Despite reductions in age-standardised incidence and mortality rates, oesophageal cancer remains a major cause of cancer mortality and burden across the world. Oesophageal cancer is a highly fatal disease, requiring increased primary prevention efforts and, possibly, screening in some high-risk areas. Substantial variation exists in age-standardised incidence rates across regions and countries, for reasons that are unclear
The global, regional, and national burden of cirrhosis by cause in 195 countries and territories, 1990-2017 : a systematic analysis for the Global Burden of Disease Study 2017
Background Cirrhosis and other chronic liver diseases (collectively referred to as cirrhosis in this paper) are a major cause of morbidity and mortality globally, although the burden and underlying causes differ across locations and demographic groups. We report on results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 on the burden of cirrhosis and its trends since 1990, by cause, sex, and age, for 195 countries and territories. Methods We used data from vital registrations, vital registration samples, and verbal autopsies to estimate mortality. We modelled prevalence of total, compensated, and decompensated cirrhosis on the basis of hospital and claims data. Disability-adjusted life-years (DALYs) were calculated as the sum of years of life lost due to premature death and years lived with disability. Estimates are presented as numbers and age-standardised or age-specific rates per 100 000 population, with 95% uncertainty intervals (UIs). All estimates are presented for five causes of cirrhosis: hepatitis B, hepatitis C, alcohol-related liver disease, non-alcoholic steatohepatitis (NASH), and other causes. We compared mortality, prevalence, and DALY estimates with those expected according to the Socio-demographic Index (SDI) as a proxy for the development status of regions and countries. Findings In 2017, cirrhosis caused more than 1.32 million (95% UI 1.27-1.45) deaths (440000 [416 000-518 000; 33.3%] in females and 883 000 [838 000-967 000; 66.7%] in males) globally, compared with less than 899 000 (829 000-948 000) deaths in 1990. Deaths due to cirrhosis constituted 2.4% (2.3-2.6) of total deaths globally in 2017 compared with 1.9% (1.8-2.0) in 1990. Despite an increase in the number of deaths, the age-standardised death rate decreased from 21.0 (19.2-22.3) per 100 000 population in 1990 to 16.5 (15.8-18-1) per 100 000 population in 2017. Sub-Saharan Africa had the highest age-standardised death rate among GBD super-regions for all years of the study period (32.2 [25.8-38.6] deaths per 100 000 population in 2017), and the high-income super-region had the lowest (10.1 [9.8-10-5] deaths per 100 000 population in 2017). The age-standardised death rate decreased or remained constant from 1990 to 2017 in all GBD regions except eastern Europe and central Asia, where the age-standardised death rate increased, primarily due to increases in alcohol-related liver disease prevalence. At the national level, the age-standardised death rate of cirrhosis was lowest in Singapore in 2017 (3.7 [3.3-4.0] per 100 000 in 2017) and highest in Egypt in all years since 1990 (103.3 [64.4-133.4] per 100 000 in 2017). There were 10.6 million (10.3-10.9) prevalent cases of decompensated cirrhosis and 112 million (107-119) prevalent cases of compensated cirrhosis globally in 2017. There was a significant increase in age-standardised prevalence rate of decompensated cirrhosis between 1990 and 2017. Cirrhosis caused by NASH had a steady age-standardised death rate throughout the study period, whereas the other four causes showed declines in age-standardised death rate. The age-standardised prevalence of compensated and decompensated cirrhosis due to NASH increased more than for any other cause of cirrhosis (by 33.2% for compensated cirrhosis and 54.8% for decompensated cirrhosis) over the study period. From 1990 to 2017, the number of prevalent cases snore than doubled for compensated cirrhosis due to NASH and more than tripled for decompensated cirrhosis due to NASH. In 2017, age-standardised death and DALY rates were lower among countries and territories with higher SDI. Interpretation Cirrhosis imposes a substantial health burden on many countries and this burden has increased at the global level since 1990, partly due to population growth and ageing. Although the age-standardised death and DALY rates of cirrhosis decreased from 1990 to 2017, numbers of deaths and DALYs and the proportion of all global deaths due to cirrhosis increased. Despite the availability of effective interventions for the prevention and treatment of hepatitis B and C, they were still the main causes of cirrhosis burden worldwide, particularly in low-income countries. The impact of hepatitis B and C is expected to be attenuated and overtaken by that of NASH in the near future. Cost-effective interventions are required to continue the prevention and treatment of viral hepatitis, and to achieve early diagnosis and prevention of cirrhosis due to alcohol-related liver disease and NASH. Copyright (C) 2020 The Author(s). Published by Elsevier Ltd.Peer reviewe
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