Posterior Reversible Encephalopathy Syndrome in Pediatric Hematopoietic Stem Cell Transplantation with Beta Major Thalassemia: The Association between the PRES Occurrence and Class of Beta Major Thalassemia

INTRODUCTION

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only definitive curative option for β-major thalassemia patients (β-MT). Posterior reversible encephalopathy syndrome (PRES) is a pervasive neurological complication which typically occurs following HSCT. β-MT patients are prone to a higher PRES incidence due to long-term immunosuppression; thus, it is imperative that these patients are closely monitored for PRES after HSCT.

PATIENTS AND METHODS

We included 148 pediatric patients with β-MT who underwent HSCT between March 2015 and August 2022 in Children's Medical Center. Patients in this study were divided into two groups. The association between PRES and class of β-MT and other risk factors were assessed and the overall survival rate was determined.

RESULTS

Fourteen out of 112 patients (12%) with class I and II β-MT developed PRES. However, PRES occurred in 11 out of 36 patients (30.5%) with β-MT-III. Our results indicated that there was a significant association between class III β-MT and the occurrence of (P = .004). Additionally, acute graft-versus-host disease (aGVHD) occurred in 80% and 44.7% of patients in the PRES and non-PRES groups, respectively (P = .001). The results of the Kaplan-Meier analysis revealed that the 5-year overall survival (OS) was 75.6% in the PRES group versus 95% in the non-PRES group, which was statistically significant (P = .001).

CONCLUSION

Based on our results, pediatric β-MT III patients are at a higher risk of developing PRES. Additionally, pediatric β-MT patients with a history of aGVHD, regardless of disease class, are more likely to develop PRES. Considering these results, PRES has a higher chance of being the etiology of symptoms and should be considered more often in these patients.

A five-year systematic review and meta-analysis study on methicillin resistant Staphylococcus epidermidis strains in Iran

Background and Objectives: One of the most prevalent drug-resistant bacteria is methicillin-resistant Staphylococcus epi- dermidis (MRSE) causing healthcare infections. Previously, a meta-analysis study on the frequency of MRSE was conducted from Mar 2006 to Jan 2016 in Iran. The present study aimed to evaluate the changes in this prevalence in the last 5 years in different cities in Iran. Materials and Methods: Published articles on the frequency of MRSE were collected from the Web of Science, PubMed, Scopus, Google Scholar, Cochrane Library, and Iranian databases from the beginning of 2016 to the end of 2020. Of the 503 records identified, 17 studies met the inclusion criteria, and their extracted data were analyzed using comprehensive meta-analysis version 2.0 (Biostat). Results: The analysis showed that the frequency of MRSE has decreased significantly in the last five years and reached 60.8 [95% confidence interval (95% CI) 54.2-66.9] among culture-positive cases of S. epidermidis in Iran. Conclusion: The noticeable reduction in the prevalence of MRSE in Iran could be due to the improvement of infection con- trol programs and interruption of the pathogen transmission cycle. Another influential reason is the significant reduction in methicillin prescriptions by physicians for infections caused by staphylococci.

Molecular Epidemiology and Recycling of Staphylococcus aureus Resistant to Methicillin Among the Staff, Patients, and Surfaces in University Hospital in West Iran, Ilam

BACKGROUND

Staphylococcus aureus is a human pathogen causing nosocomial infections and increased hospitalization and mortality among human communities. Methicillin-resistant S. aureus strains are considered a severe threat in nosocomial infections and cause complications in the remedy process of bacterial infections. In this study, 137 samples were collected from different departments, staff, and patients in Ilam hospital.

METHODS

Eighty-eight samples of these strains were examined to test antibiotic resistance and diffusion. MIC (minimum inhibitory concentration) and PCR (polymerase chain reaction) were performed on the samples resistant to oxacillin. 36 (40.9%) strains were MRSA, and 52 (59.1%) isolates were MSSA. 44.4% of MRSA strains with IV SCCmec type.

RESULTS

Fourteen different spa types were found using spa typing, of which the most abundant types were t037, t030, and t701, and three new types, including t15471, t15474, and t17470, were identified among the strains. The molecular analysis by MLST showed that the strains are classified into 11 different sequence types. Sequence type 239 and clonal complexes of 329 and 22 were dominant. ST239- spat037-SCCmec III was also identified as the most frequent clone of MRSA. The most identified clones were MRSA ST239-spa t037-SCCmec III.

CONCLUSION

The results show the spa-type distribution between samples of patients, personnel, and surfaces, demonstrating MRSA circulation between patients and the environment. The results show the need to control environmental health.

Acute myocarditis and acute myopathy as the first manifestations of COVID-19; a case report

Coronavirus disease 2019 (COVID-19) mainly manifests with flu-like and respiratory symptoms such as fever, chill, myalgia, cough, dyspnea and in severe cases, it leads to acute respiratory distress syndrome and respiratory failure. However, there is evidence of extra-pulmonary involvements in patients with COVID-19. Some case reports and studies have reported severe and life-threatening complications related to COVID-19 such as cardiovascular complications (acute heart failure, myocarditis, acute coronary syndrome, thromboembolic events) and neuromuscular complications (stroke, transient ischemic attack, myositis, myopathy, Guillain-Barre syndrome). Here, we report a 51-year-old woman without a previous history of cardiovascular disease or neuromuscular disease referred to the emergency department of our hospital with new onset severe respiratory distress and progressive symmetric quadriparesis. We concluded that, the patient was infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and we therefore have encountered acute myocarditis and acute myopathy due to COVID-19 disease. In the intensive care unit (ICU), the patient was treated with oxygen therapy without mechanical ventilation, dexamethasone, intravenous human immunoglobulin (IVIG), beta interferon and remdesivir. The clinical feature, cardiac, respiratory, neuromuscular and hemodynamic parameters improved clearly five days after taking above mentioned treatments. The troponin, N-terminal pro-B type natriuretic peptide (NTproBNP), creatine phosphokinase (CPK), returned to normal values. Following improvement of cardiac and neurologic problems, the patient was transferred from ICU to general ward and then after 10 days, she was discharged with oral anticoagulant, anti-platelet, low-dose of corticosteroids and other conservative treatments.

Evaluation of the effect of ibuprofen in combination with ciprofloxacin on the virulence-associated traits, and efflux pump genes of Pseudomonas aeruginosa

Biofilm formation and antibiotic efflux are two determinant factors in the development of drug resistance phenotype by Pseudomonas aeruginosa. Non-steroid anti-inflammatory drugs have shown the antimicrobial potential to be used in combination with antibiotics against bacterial pathogens. In this work, the effect of ibuprofen alone and in combination with ciprofloxacin on some virulence traits and the expression of the alginate synthesis and efflux pump genes of clinical isolates of P. aeruginosa was investigated. The checkerboard titration assay was used to evaluate the synergism of the drugs. P. aeruginosa strains were grown in the presence of sub-inhibitory concentrations of the drug and their biofilm formation level, swarming, swimming, and hemolytic activity were assessed. Also, the relative expression of the alg44, algT/U, mexB, and oprM genes was determined by qPCR assay. The MIC of ibuprofen and ciprofloxacin were measured 2048 and 32 µg/mL and the drugs showed synergic antibacterial activity (FIC = 0.4). Moreover, ibuprofen alone and in combination with ciprofloxacin, significantly reduced the expression of alg44 (0.22 and 0.25 folds) and algT/U (0.26 and 0.37 folds) genes, while increased the expression of the mexB (1.64 and 1.83 folds) and oprM (1.36 and 1.92 folds) genes. Simultaneous treatment of bacterial cells with ibuprofen and ciprofloxacin significantly decreased bacterial biofilm formation (65%), swimming, swarming, and hemolytic activity (85%), compared with the control. This work suggests that ibuprofen has considerable anti-virulence potential against P. aeruginosa and could be employed for combination therapy with antibiotics after further characterizations.

Performance of a machine-learning algorithm for fully automatic LGE scar quantification in the large multi-national derivate registry

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): J. Schwitter receives research support by “ Bayer Schweiz AG “. C.N.C. received grant by Siemens. Gianluca Pontone received institutional fees by General Electric, Bracco, Heartflow, Medtronic, and Bayer. U.J.S received grand by Astellas, Bayer, General Electric. This work was supported by Italian Ministry of Health, Rome, Italy (RC 2017 R659/17-CCM698). This work was supported by Gyrotools, Zurich, Switzerland.

Background

 Late Gadolinium enhancement (LGE) scar quantification is generally recognized as an accurate and reproducible technique, but it is observer-dependent and time consuming. Machine learning (ML) potentially offers to solve this problem. 

Purpose

 to develop and validate a ML-algorithm to allow for scar quantification thereby fully avoiding observer variability, and to apply this algorithm to the prospective international multicentre Derivate cohort.

Method

 The Derivate Registry collected heart failure patients with LV ejection fraction <50% in 20 European and US centres. In the post-myocardial infarction patients (n = 689) quality of the LGE short-axis breath-hold images was determined (good, acceptable, sufficient, borderline, poor, excluded) and ground truth (GT) was produced (endo-epicardial contours, 2 remote reference regions, artefact elimination) to determine mass of non-infarcted myocardium and of dense (≥5SD above mean-remote) and non-dense scar (>2SD to <5SD above mean-remote). Data were divided into the learning (total n = 573; training: n = 289; testing: n = 284) and validation set (n = 116). A Ternaus-network (loss function = average of dice and binary-cross-entropy) produced 4 outputs (initial prediction, test time augmentation (TTA), threshold-based prediction (TB), and TTA + TB) representing normal myocardium, non-dense, and dense scar (Figure 1).Outputs were evaluated by dice metrics, Bland-Altman, and correlations. 

Results

 In the validation and test data sets, both not used for training, the dense scar GT was 20.8 ± 9.6% and 21.9 ± 13.3% of LV mass, respectively. The TTA-network yielded the best results with small biases vs GT (-2.2 ± 6.1%, p < 0.02; -1.7 ± 6.0%, p < 0.003, respectively) and 95%CI vs GT in the range of inter-human comparisons, i.e. TTA yielded SD of the differences vs GT in the validation and test data of 6.1 and 6.0 percentage points (%p), respectively (Fig 2), which was comparable to the 7.7%p for the inter-observer comparison (n = 40). For non-dense scar, TTA performance was similar with small biases (-1.9 ± 8.6%, p < 0.0005, -1.4 ± 8.2%, p < 0.0001, in the validation and test sets, respectively, GT 39.2 ± 13.8% and 42.1 ± 14.2%) and acceptable 95%CI with SD of the differences of 8.6 and 8.2%p for TTA vs GT, respectively, and 9.3%p for inter-observer. 

Conclusions

 In the large Derivate cohort from 20 centres, performance of the presented ML-algorithm to quantify dense and non-dense scar fully automatically is comparable to that of experienced humans with small bias and acceptable 95%-CI. Such a tool could facilitate scar quantification in clinical routine as it eliminates human observer variability and can handle large data sets.

Safety of Same-Day Discharge After Percutaneous Coronary Intervention in Selected Patients With Non-ST Elevation Acute Coronary Syndrome

OBJECTIVES

We aimed to investigate the safety of same-day discharge (SDD) after percutaneous coronary intervention (PCI) for non-ST segment elevation acute coronary syndrome (NSTEACS), and to investigate the reduction in duration of hospitalization achievable by SDD.

BACKGROUND

Previous studies have established the safety of SDD after elective PCI, while the safety of SDD after non-elective PCI for acute coronary syndrome has only been sparsely studied.

METHODS

A single-center, observational, retrospective study of 923 consecutive procedures in patients with NSTEACS who had PCI was performed. The procedures were divided into 2 groups based on postprocedural management: SDD (n = 195) and non-SDD (n = 728).

RESULTS

No differences were seen in the total number of adverse events at 1 month (1.5% SDD vs 1.4% non-SDD; P=.74), 3 months (2.5% SDD vs 2.3% non-SDD; P=.80), and 6 months (3.5% SDD vs 3.3% non-SDD; P=.84) after discharge, and there were no deaths in the SDD group. No difference was found in unplanned rehospitalizations within 6 months (20.5% SDD vs 25.3% non-SDD; P=.17), while unplanned revascularizations were more frequent in non-SDD patients (5.6% SDD vs 13.4% non-SDD; P<.01). Median duration of hospitalization was 1.3 days shorter for SDD patients than for non-elderly, uncomplicated non-SDD patients.

CONCLUSIONS

SDD after PCI in a selected group of NSTEACS patients was associated with low rates of adverse events, unplanned rehospitalizations, and revascularizations. SDD was associated with a shorter hospitalization duration.

Phase-field modeling of constrained interactive fungal networks

Fungi develop structures that interact with their surroundings and evolve adaptively in the presence of geometrical constraints, finding optimal solutions for complex combinatorial problems. The pathogenic fungus Ophiocordyceps constitutes a perfect model for the study of constrained interactive networks. Modeling these networks is challenging due to the highly coupled physics involved and their interaction with moving boundaries. In this work, we develop a computational phase-field model to elucidate the mechanics of the emerging properties observed in fungal networks. We use a variational approach to derive the equations governing the evolution in time of the mycelium biomass and the nutrients in the medium. We present an extensive testing of our model, reproduce growing and decaying phenomena, and capture spatial and temporal scales. We explore the variables interplay mechanism that leads to different colony morphologies, and explain abrupt changes of patterns observed in the laboratory. We apply our model to simulate analogous processes to the evolution of Ophiocordyceps as it grows through confined geometry and depletes available resources, demonstrating the suitability of the formulation to study this class of biological networks.

Antibiotic resistance profiles of Salmonella serotypes isolated from animals in Iran: a meta-analysis

BACKGROUND

Salmonella infection (salmonellosis) is a zoonotic bacterial disease. Widespread use of antibiotics in livestock and poultry production for different purposes such as treatment and growth promotion has led to the emergence of antibiotic-resistant Salmonella, causing treatment of Salmonella infections more difficult with each passing year.

AIMS

To determine the antibiotic resistance prevalence of Salmonella serotypes isolated from animals in different provinces of Iran.

METHODS

To find eligible articles, we searched the international and national electronic databases using appropriate keywords in English and Persian.

RESULTS

After applying predefined criteria, 54 articles reporting antibiotic resistance profiles of Salmonella serotypes were included. Salmonella isolates were mostly resistant against nalidixic acid (67%), tetracycline (66.9%), and streptomycin (49.6%), followed by trimethoprim/sulfamethoxazole (41.6%) and kanamycin (23.6%). The highest sensitivity was observed against imipenem, meropenem, and cefepime with 1.7%, 1.4%, and 1.9% of all isolates being resistant, respectively.

CONCLUSION

Results revealed that the prevalence of resistant isolates to nalidixic acid, tetracycline and streptomycin is high and their use must be restricted. In addition, resistance to other antibiotics such as chloramphenicol, ampicillin, cephalothin, cefixime, and enrofloxacin is at an alarming level that calls for attention in the future infection control and antibiotic stewardship programs.

Ameliorative effect of cotreatment with the methanolic leaf extract of Urtica dioica on acute kidney injury induced by gentamicin in rats

OBJECTIVE

Effects of cotreatment with Urtica dioica (UD) methanolic leaf extract on gentamicin (GM)-induced acute kidney injury were evaluated in rats.

MATERIALS AND METHODS

Male Wistar rats (n=32) were separated into four groups. Gentamicin (100 mg/kg/day, IP) was injected for eight days with or without UD methanolic extract (200 mg/kg/day, gavage).  The renal blood flow (RBF) and systolic blood pressure of rats were recorded. Concentration of creatinine, blood urea nitrogen (BUN), sodium, and potassium and osmolarity were measured in the urine and plasma samples. Oxidative stress level was determined by assessment of the levels of antioxidant power (FRAP) and lipid peroxidation (MDA) in the renal tissue. The renal injury and histopathological changes in the kidney were determined by microscopic evaluations.

RESULTS

Administration of UD extract along with GM, compared to GM group, significantly decreased the amounts of plasma creatinine and BUN, urinary sodium excretion, fractional excretion of sodium and potassium, and MDA levels but significantly increased creatinine clearance, urine osmolarity, renal blood flow and FRAP levels.

CONCLUSION

The cotreatment of UD extract can attenuate renal injury of GM by reduction of oxidative stress, lipid peroxidation, and oxygen free radicals. The potential nephroprotective effects of UD extract are probably mediated via its antioxidant and anti-inflammatory activity.

Association of Betaine-Homocysteine S-Methyl Transferase (rs3797546 and rs3733890) polymorphisms with non-syndromic cleft lip/palate: A meta-analysis

OBJECTIVE

Non-syndromic cleft lip/palate (NSCL/P) has a multifactorial and polygenic aetiology. The role of genetics in its occurrence has not been fully clarified. The present meta-analysis aimed to evaluate the association of betaine-homocysteine S-methyltransferase (BHMT) polymorphisms (rs3797546 and rs3733890) with the risk of NSCL/P.

MATERIALS AND METHODS

PubMed/Medline, Scopus, Cochrane Library, and Web of Science databases were systematically searched for articles published up until December 2018 with no language restriction. Quality evaluation of each study was performed by the Newcastle-Ottawa Scale (NOS). The crude odds ratio (OR) and 95% confidence interval (CI) were calculated for each study by RevMan 5.3 software, and a funnel plot analysis was performed by the CMA 2.0 software using the Egger's and Begg's tests.

RESULTS

Review of the four selected studies revealed that the CC genotype of rs3797546 polymorphism significantly increased the risk of NSCL/P. No association was noted between NSCL/P risk and rs3733890 polymorphism except in Chinese (elevated risk of NSCL/P) and Polish (decreased risk of NSCL/P) populations.

CONCLUSIONS

According to the present meta-analysis, rs3733890 polymorphism does not play a role in susceptibility to NSCL/P; whereas, rs3797546 polymorphism may play a role in susceptibility to NSCL/P. Future studies are required to examine the association between BHMT polymorphisms and the NSCL/P risk in different ethnicities with a larger sample size.

Effects of Nitroglycerine on Renal Ischemia-Reperfusion Injury in Adult Male Rats

BACKGROUND

Ischemia-reperfusion (I-R) leads to acute kidney injury (AKI). The present study investigated the effects of nitroglycerine (NG) on improving renal dysfunctions caused by I-R in rats.

METHODOLOGY

Twenty-four rats were equally divided into four groups: (1) the control group, (2) the sham group, (3) the I-R group, and (4) NG-treated groups.NG (50 μg/kg) was injected intraperitoneally after induction of IR. I-R was induced through clamping of the bilateral renal artery and vein of both kidneys for 20 min followed by 24 h of reperfusion.

RESULTS

NG significantly increased the creatinine clearance levels and renal blood flow rate (which was reduced by I-R). NG also significantly improved serum electrolytes (sodium and potassium) that were disordered by I-R. In addition, NG significantly offset impaired antioxidant defense mechanism and inhibited lipid peroxidation.

CONCLUSIONS

The results show NG has a protective effect on renal tissue against AKI caused by I-R. These protective effects mediated through antioxidant activity and decrease of lipid peroxidation.

Ameliorative Effects of Zataria Multiflora Hydro-Alcoholic extract on Gentamicin Induced Nephrotoxicity in Rats

BACKGROUND

Nephrotoxicity is the major side effects of aminoglycoside antibiotics such as gentamicin. The aim of this study was to investigate the therapeutic effects of Z.multiflora (ZM) hydroalcoholic extract on gentamicin-induced nephrotoxicity.

METHODS

Twenty-eight male Wistar rats categorized into four groups: 1) the control group without injection, 2) the gentamicin treated group (100 mg/kg, i.p) 3) the gentamicin and Z. Multiflora treated group; Z. Multiflora extract(0.8 mg/ml in the drinking water) administered after gentamicin (100 mg/kg, i.p) 4) the normal saline and Z. Multiflora treated group; Z. Multiflora extract (0.8 mg/ml in the drinking water) administered after normal saline injection (2 ml/kg,i.p ).

RESULTS

Post-treatment with ZM extract caused a significant reduction in the levels of plasma creatinine and blood urea nitrogen (BUN), absolute and fractional excretion of sodium, malondialdehyed (MDA) level in comparison to gentamicin group. In addition, ZM extract significantly increased creatinine clearance, urine osmolarity, and Renal blood flow (RBF) and the Ferric reducing ability of plasma (FRAP) level which had decreased compared to the control group as a result of treatment with gentamicin.

CONCLUSION

The above result indicated that ZM extract improved renal toxicity of gentamicin via reducing oxidative stress, oxygen-free radicals, and lipid peroxidation.

Effects of Cobalamin (Vitamin B12) on Gentamicin Induced Nephrotoxicity in Rat

Background The main side effect of gentamicin is nephrotoxicity. The effect of cobalamin (Cob) was investigated on gentamicin nephrotoxicity in rats.

Methods Renal injury induced by i.p. injection of gentamicin (100 mg/kg) for 8 consecutive days. Cobalamin (6 mg/kg/day, i.p) treatment was done for 8 consecutive days as co-treatment and post-treatment protocol.

Results Cobalamin significantly increased creatinine clearance levels and renal blood flow which were reduced by gentamicin. Also, cobalamin significantly improved serum electrolytes (sodium and potassium) levels which were disturbed by gentamicin. Cobalamin significantly compensated deficits in the antioxidant defense mechanisms, suppressed lipid per oxidation and ameliorated renal tissue damage mediated by gentamicin.

Conclusion The results of the current study indicated that cobalamin effectively protected the kidney tissue against gentamicin induced acute nephrotoxicity in rats. The antioxidant and anti-inflammatory activities can be supposed the main factors responsible for the nephroprotective effect of cobalamin.

Effect of blood contamination on the compressive strength of three calcium silicate-based cements

The aim of this study was to investigate the effect of human blood exposure on the compressive strength of various calcium silicate-based cements. Two hundred and eighty-eight customised cylindrical moulds were randomly divided into three groups according to material used: ProRoot MTA, Biodentine or CEM cement (n = 96). Each group was divided into two subgroups according to exposure conditions: PBS or blood. Then, the compressive strength of the specimens was measured after 6 h, 24 h, 72 h and 7 days. The compressive strength of CEM cement could not be measured after 6 and 24‏ h regardless of the exposure conditions nor could the compressive strength of 6 h blood-exposed ProRoot MTA. The compressive strength of blood-exposed ProRoot MTA was only significantly lower after 6 h, but no difference was seen at other time intervals. Blood exposed did adversely affected the compressive strength of Biodentine. The compressive strength of all groups significantly increased over time (P < 0.005).

Mitochondrial oxidative stress and dysfunction induced by single- and multiwall carbon nanotubes: A comparative study

With the ever-increasing use of carbon nanotubes (CNTs) in health-related and engineering applications, the hazardous risks of this material have become a major concern. It is well known that CNTs accumulate with cytotoxic and genotoxic levels within vital organs. It has also been shown that treating cell cultures with CNTs resulted in cell-cycle arrest and increased apoptosis/necrosis. The goal of this pilot study is to perform a comprehensive comparative study on the toxicity of single-wall (SW) and multiwall (MW) CNTs in rat skin cells. Our results confirm a dose-dependent toxicity of SWCNTs and MWCNTs due to the loss of mitochondrial activity, increase in mitochondrial reactive oxygen species (ROS) formation, and mitochondrial membrane potential collapse before mitochondrial swelling. Moreover, disturbance in the oxidative phosphorylation is observed by a decrease in ATP level. These events induced the release of cytochrome c via outer membrane rupture or MPT pore opening and subsequently programmed cell death of all doses compared to control group. Our results demonstrate that although MWCNTs can be very toxic, SWCNTs cause more mitochondrial damage to the cells. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2047-2055, 2017.

Human health risk assessment of organophosphorus pesticide in rice crop from selected districts of Anzali International Wetland basin, Iran

Low fertility in rice caused by Chilo suppressalis has led to the use of diazinon to control this pest. Residue of pesticide could penetrate products and also food which can affect public health. The aim of this research was to determine health risk assessment of organophosphorus (OP) pesticide in rice, a strategic crop in Iran. Ninety rice samples were collected from 30 points during harvesting seasons from Rasht Area, Guilan Province, Iran from which 30 samples were prepared. The concentration of diazinon, the most common pesticide used in the study area, was determined by high-performance liquid chromatography. The result indicated that the total average of diazinon in rice samples (31.91 mg/kg) is by far higher than the maximum residue limit recommended by the European Union. According to the results, EDAI was 0.051 mg/kg day, while health risk index in rice was 10.2. Results showed that there is a health risk associated with the lifetime consumption of rice polluted by OP pesticide in the study area.

Unexpectedly high occurrence of Escherichia coli and Staphylococcus aureus isolates from raw milk in Ilam, Western Iran

Raw milk contains diverse nutritional components that provide a suitable medium for spoilage and the growth of potentially pathogenic microorganisms. Unpasteurized milk consumption by a large number of people can threaten health and increase public concerns. In this study, sixty-two raw cow’s milk samples were collected from the dairy farms of Ilam, Western Iran. All samples were collected in sterilized containers and were transferred via ice boxes to the laboratory. Isolates were then identified by standard methods. Totally, 88.7% (n=55) of samples were contaminated. Our study also showed that Escherichia coli had a high prevalence among isolates (43: 69.4%), while Klebsiella pneumoniae and Klebsiella planticola showed the lowest prevalence (1: 1.6%). Staphylococcus aureus was also detected in 17.7% (n=11) of samples. The raw milk microbial contamination is complex. Some of the microorganisms threaten public health via different traits, therefore it is recommended that raw milk consumption should be avoided.

Acinetobacter baumannii clonal lineages I and II harboring different carbapenem-hydrolyzing-β-lactamase genes are widespread among hospitalized burn patients in Tehran

The aim of this study was to analyze antimicrobial resistance patterns and their encoding genes and genotypic diversity of Acinetobacter baumannii isolated from burn patients in Tehran, Iran. The presence of extended-spectrum beta-lactamase- and blaOXA-encoding genes among 37 multidrug resistant (MDR) A. baumannii strains isolated from patients hospitalized in a teaching hospital in Tehran was evaluated. Susceptibility to 7 antibiotics was tested by disk agar diffusion and to polymyxin B and colistin was tested by E-test, according to CLSI guidelines. All isolates were then analyzed by PCR for the presence of blaIMP, blaVIM, blaSIMblaOXA-23, blaOXA-24, and blaOXA-58-like carbapenemase genes, and blaOXA-51-like, blaTEM, blaSHV, blaPER, blaVEB, and blaGIM genes. Genotyping of A. baumannii strains was performed by repetitive sequence-based (REP)-PCR and cluster analysis of REP-PCR profiles. A. baumannii isolates were assigned to international clones by multiplex PCR sequence group analysis. Twenty-five A. baumannii isolates were classified as MDR, and 12 were classified as extensively drug resistant. All isolates were susceptible to colistin and polymyxin B. Eighty-one percent of the isolates was resistant to imipenem or meropenem and harbored at least one or both of the blaOXA-23-like or blaOXA-24-like carbapenemase genes. Co-existence of different resistance genes was found among carbapenem-resistant isolates. Multiplex PCR sequence group analysis most commonly assigned A. baumannii isolates to international clones I (18/37; 48.6%) and II (18/37; 48.6%). An alarming increase in resistance to carbapenems and the spread of blaOXA-23-like and/or blaOXA-24-like carbapenemase genes was observed among A. baumannii strains belonging to clonal lineages I and II, isolated from burn patients in Tehran.

Determination of selenium in serum samples of preterm newborn infants with bronchopulmonary dysplasia using a validated hydride generation system

Bronchopulmonary dysplasia (BPD), also known as chronic lung disease, is one of the most challenging complications in premature newborn infants. Selenium plays a role in antioxidant system by protecting cell membranes and neutralizing the deleterious effects of free radicals. The aim of this study was to determine the relationship between selenium concentration and incidence of bronchopulmonary dysplasia using a validated analytical method. Umbilical cord blood and blood samples 30 days after the birth were collected from 38 preterm newborn infants with gestation age of 32 weeks or less, and the separated serums were kept at -70°C until analysis time. Selenium concentration of serum was determined using an atomic absorption spectrophotometer. The method was validated on the basis of standard validation techniques. The analytical method was linear in the range of 1 to 500 μg/L with the limit of detection of 0.4 μg/L. Samples were collected from 38 infants whose gestation age was 32 weeks or less. The blood samples were collected from the umbilical cord blood at birth in 19 cases. In 25 cases, blood samples were collected 1 month after birth. Of the 15 patients diagnosed with BPD, 10 were boys (p = 0.02). The mean serum selenium concentration was not different at birth between patients with and without BPD, but it was significantly lower at 30 days after birth in patients with BPD (38.5 ± 14.1vs. 45.4 ± 18.7 μg/L, p = 0.02). Preterm newborn infants with BPD had lower serum selenium concentrations 1 month after birth.

A new method for environmental site assessment of urban solid waste landfills

Regarding various types of pollutant, waste management requires high attention. Environmental site selection study, prior to landfill operation, and subsequently, monitoring and maintaining of the location, are of foremost points in landfill site selection process. By means of these studies, it is possible to control the undesirable impacts caused by landfills. Study ahead aims at examination of effectiveness of a new method called Monavari 95-2 in landfill site assessment. For this purpose, two landfills Rasht and Andisheh, which are, respectively, located on humid and arid areas, were selected as case studies. Then, the results obtained from both sites were compared with each other to find out the weaknesses and strengths of each site. Compared with others similar methods, much more criteria (53 parameters) can be considered within this method, so the results will be more calculable. According to this method, Rasht landfill (site H) is classified as unacceptable landfill site i.e. there is an urgent need for a new suitable site for landfill, while Andishe Landfill (site D) is ranked as acceptable landfill site but needs environmental management program to handle the existing weaknesses.

A Critical Evaluation of the Experimental Design of Studies of Mechanism Based Enzyme Inhibition, with Implications for In Vitro-In Vivo Extrapolation

The published literature on mechanism based inhibition (MBI) of CYPs was evaluated with respect to experimental design, methodology and data analysis. Significant variation was apparent in the dilution factor, ratio of preincubation to incubation times and probe substrate concentrations used, and there were some anomalies in the estimation of associated kinetic parameters (k(inact), K(I), r). The impact of the application of inaccurate values of k(inact) and K(I) when extrapolating to the extent of inhibition in vivo is likely to be greatest for those compounds of intermediate inhibitory potency, but this also depends on the fraction of the net clearance of substrate subject to MBI and the pre-systemic and systemic exposure to the inhibitor. For potent inhibitors, the experimental procedure is unlikely to have a material influence on the maximum inhibition. Nevertheless, the bias in the values of the kinetic parameters may influence the time for recovery of enzyme activity following re-synthesis of the enzyme. Careful attention to the design of in vitro experiments to obtain accurate kinetic parameters is necessary for a reliable prediction of different aspects of the in vivo consequences of MBI. The review calls for experimental studies to quantify the impact of study design in studies of MBI, with a view to better harmonisation of protocols.