204 research outputs found
Optimization of a Modified GS Medium for a Probiotic Strain (L. acidophilus ATCC4356)
Probiotics are defined as living microorganisms with beneficial effects on the host. Probiotics, according to the least negative effect on the body, are considered as a good alternative to chemical drugs. Lactobacillus acidophilus is used as a probiotic that is able to reduce cholesterol level in the blood. The effect of various concentrations of carbon, nitrogen and phosphorus for enhancing the biomass production of Lactobacillus acidophilus was examined. The response surface methodology based on Box–Wilson CCD was applied to explore the optimal medium composition. Glucose, yeast extract, K2HPO4 and KH2PO4 were selected as dependent variables. All experiments were run at 37°C for 31h under stationary conditions. By solving the regression equation and analyzing the response surface carton, optimal concentrations of the components were determined as glucose (5-8.75 g.l-1), yeast extract (36.75-39 g.l-1), K2HPO4 (0.1-0.2125 g.l-1) and KH2PO4 (0.3925-0.7075 g.l-1). Validation experiment confirmed that the optimized medium was comparable to the MRS medium (the most common medium for Lactobacillus acidophilus strain) in biomass production, having the advantages of economy andpracticality
Socio-economic, cultural, physical and ecological impact assessment of Kavar irrigation and drainage network in Iran
Environmental impacts assessment may be some measures to offset the impact to an acceptable level or explore new solutions. The research was conducted with the aim of assessing the socio-economic, cultural, physical and ecological impacts of Kavar irrigation and drainage network in Fars Province (Iran). In this study, Environmental impacts assessment was undertaken by ICOLD matrix. The ICOLD matrix is one of the flexible methods that converted qualitative data into quantitative data. In this method, the effect of the project activities on the environmental components were assessed in two stages; project construction and operation based on physical, ecological, socio-economic and cultural aspects. The findings indicated that positive effects will be generally exerted on the region environment by establishing and operating irrigation and drainage network in Kavar plain. In other words, substantial positive impacts will be seen in the region consequently; such as improving the average level of aquifer, enhancement of agricultural wells, and agriculture development in the region. However, in order to alleviate the negative impacts of the projects processes, it is suggested that presented environmental training to farmers, collaborating and further communicating with other relevant organizations and institutions. </strong
Pseudogap phase of cuprate superconductors confined by Fermi surface topology
The properties of cuprate high-temperature superconductors are largely shaped
by competing phases whose nature is often a mystery. Chiefly among them is the
pseudogap phase, which sets in at a doping that is material-dependent.
What determines is currently an open question. Here we show that the
pseudogap cannot open on an electron-like Fermi surface, and can only exist
below the doping at which the large Fermi surface goes from hole-like
to electron-like, so that . We derive this result from
high-magnetic-field transport measurements in
LaNdSrCuO under pressure, which reveal a large and
unexpected shift of with pressure, driven by a corresponding shift in
. This necessary condition for pseudogap formation, imposed by details
of the Fermi surface, is a strong constraint for theories of the pseudogap
phase. Our finding that can be tuned with a modest pressure opens a new
route for experimental studies of the pseudogap.Comment: 15 pages, 5 figures, 7 supplemental figure
Presence and diversity of Leishmania RNA virus in an old zoonotic cutaneous leishmaniasis focus, northeastern Iran: haplotype and phylogenetic based approach
Objective: Leishmania RNA virus (LRV) is a double-stranded RNA (dsRNA) virus that circulates within many species of the Leishmania parasite. In this study, we aimed to investigate the presence of LRV2 circulating in Leishmania isolates in an old focus of ZCL located in northeastern of Iran. Methods: Leishmania isolates were collected from 85 patients that confirmed to have cutaneous leishmaniasis (CL) based on parasitological examination. To identify the Leishmania isolates, species-specific primer sets were applied for molecular identification. The presence of LRV2 was performed by RdRp-semi nested-PCR. The genetic diversity were calculated using MEGA and DnaSP. To assess haplotype diversity, 31 LRV2 strains in different regions were surveyed using analysis a 292-bp section of the RdRp sequences. Results: Out of 85 patients, 83 (97.6 ) were diagnosed with L. major and 2 (2.4 ) with L. tropica. LRV2 virus was detected in 59 (69.4) of the CL cases. For the first time, LRV2 was reported in one L. tropica strain in Iran. The current LRV2 sequences indicated the highest similarities to an Old World LRV2. Moreover, 10 unique haplotypes were identified based on the analyzed sequences of the RdRp gene. Conclusions: Our results indicated the highest occurrence of Leishmania/LRV2 co-circulation in this known ZCL focus from northeastern Iran. Phylogenetic analyses of LRV2 sequences confirmed that these isolates belong to the order of LRV2 from the Old World. This study offered an insight into LRV2 haplotype that the informative issue can be used for genetic research of LRV2 in other regions. © 2020 The Author(s
The status of hepatitis C virus infection among people who inject drugs in the Middle East and North Africa.
BACKGROUND AND AIMS: People who inject drugs (PWID) are a key population at high risk of hepatitis C virus (HCV) infection. The aim of this study was to delineate the epidemiology of HCV in PWID in the Middle East and North Africa (MENA). METHODS: Syntheses of data were conducted on the standardized and systematically assembled databases of the MENA HCV Epidemiology Synthesis Project, 1989-2018. Random-effects meta-analyses and meta-regressions were performed. Meta-regression variables included country, study site, year of data collection and year of publication [to assess trends in HCV antibody prevalence over time], sample size and sampling methodology. Numbers of chronically infected PWID across MENA were estimated. The Shannon Diversity Index was calculated to assess genotype diversity. RESULTS: Based on 118 HCV antibody prevalence measures, the pooled mean prevalence in PWID for all MENA was 49.3% [95% confidence interval (CI) = 44.4-54.1%]. The country-specific pooled mean ranged from 21.7% (95% CI = 4.9-38.6%) in Tunisia to 94.2% (95% CI = 90.8-96.7%) in Libya. An estimated 221 704 PWID were chronically infected, with the largest numbers found in Iran at 68 526 and in Pakistan at 46 554. There was no statistically significant evidence for a decline in HCV antibody prevalence over time. Genotype diversity was moderate (Shannon Diversity Index of 1.01 out of 1.95; 52.1%). The pooled mean percentage for each HCV genotype was highest in genotype 3 (42.7%) and in genotype 1 (35.9%). CONCLUSION: Half of people who inject drugs in the Middle East and North Africa appear to have ever been infected with hepatitis C virus, but there are large variations in antibody prevalence among countries. In addition to > 200 000 chronically infected current people who inject drugs, there is an unknown number of people who no longer inject drugs who may have acquired hepatitis C virus during past injecting drug use. Harm reduction services must be expanded, and innovative strategies need to be employed to ensure accessibility to hepatitis C virus testing and treatment
PCR Targeting Plasmodium Mitochondrial Genome of DNA Extracted from Dried Blood on Filter Paper Compared to Whole Blood.
Monitoring mortality and morbidity attributable to malaria is paramount to achieve elimination of malaria. Diagnosis of malaria is challenging and PCR is a reliable method for identifying malaria with high sensitivity. However, blood specimen collection and transport can be challenging and obtaining dried blood spots (DBS) on filter paper by finger-prick may have advantages over collecting whole blood by venepuncture. DBS and whole blood were collected from febrile children admitted at the general paediatric wards at a referral hospital in Dar es Salaam, Tanzania. DNA extracted from whole blood and from DBS was tested with a genus-specific PCR targeting the mitochondrial Plasmodium genome. Positive samples by PCR of DNA from whole blood were tested with species-specific PCR targeting the 18S rRNA locus, or sequencing if species-specific PCR was negative. Rapid diagnostic test (RDT) and thin blood smear microscopy was carried out on all patients where remnant whole blood and a blood slide, respectively, were available. Positivity of PCR was 24.5 (78/319) and 11.2% (52/442) by whole blood and DBS, respectively. All samples positive on DBS were also positive on Plasmodium falciparum species-specific PCR. All RDT positive cases were also positive by DBS PCR. All but three cases with positive blood slides were also positive by DBS. In this study, PCR for malaria mitochondrial DNA extracted from whole blood was more sensitive than from DBS. However, DBS are a practical alternative to whole blood and detected approximately the same number of cases as RDTs and, therefore, remain relevant for research purposes
Fungal peritonitis in Iranian children on continuous ambulatory peritoneal dialysis: a national experience.
INTRODUCTION. Fungal peritonitis (FP), causing catheter obstruction, dialysis failure, and peritoneal dysfunction, is a rare but serious complication of peritoneal dialysis. In this study, the frequency and risk factors of FP are evaluated in children who underwent peritoneal dialysis. MATERIALS AND METHODS. A retrospective multicenter study was performed at the 5 pediatric peritoneal dialysis centers in Iran from 1971 to 2006, and FP episodes among 93 children were reviewed. Risk ratios were calculated for the clinical and demographic variables to determine the risk factors of FP. RESULTS. Ninety-three children aged 39 months on average were included in study. Sixteen out of 155 episodes of peritonitis were fungi infections, all by Candida albicans. The risk of FP was higher in those with relapsing bacterial peritonitis (P = .009). Also, all of the patients had received antibiotics within the 1 month prior to the development of FP. Catheters were removed in all patients after 1 to 7 days of developing FP. Six out of 12 patients had catheter obstruction and peritoneal loss after the treatment and 5 died due to infection. CONCLUSIONS. Fungal peritonitis, accompanied by high morbidity and mortality in children should be reduced by prevention of bacterial peritonitis. Early removal of catheter after recognition of FP should be considered
Fungal peritonitis in Iranian children on continuous ambulatory peritoneal dialysis: a national experience.
INTRODUCTION. Fungal peritonitis (FP), causing catheter obstruction, dialysis failure, and peritoneal dysfunction, is a rare but serious complication of peritoneal dialysis. In this study, the frequency and risk factors of FP are evaluated in children who underwent peritoneal dialysis. MATERIALS AND METHODS. A retrospective multicenter study was performed at the 5 pediatric peritoneal dialysis centers in Iran from 1971 to 2006, and FP episodes among 93 children were reviewed. Risk ratios were calculated for the clinical and demographic variables to determine the risk factors of FP. RESULTS. Ninety-three children aged 39 months on average were included in study. Sixteen out of 155 episodes of peritonitis were fungi infections, all by Candida albicans. The risk of FP was higher in those with relapsing bacterial peritonitis (P = .009). Also, all of the patients had received antibiotics within the 1 month prior to the development of FP. Catheters were removed in all patients after 1 to 7 days of developing FP. Six out of 12 patients had catheter obstruction and peritoneal loss after the treatment and 5 died due to infection. CONCLUSIONS. Fungal peritonitis, accompanied by high morbidity and mortality in children should be reduced by prevention of bacterial peritonitis. Early removal of catheter after recognition of FP should be considered
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