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Objective: Early and accurate diagnosis of bacterial meningitis is of critical concern. Optimum and rapid laboratory facilities are not routinely available for detecting the etiologic agents of meningitis. The objective of this study was to compare polymerase chain reaction (PCR) assay with culture for detection of bacteria in central nervous system (CNS) samples from patients suspected to have meningitis. Methods: One-hundred CSF samples were obtained and divided into two parts. One part of samples was used for standard bacterial culture and gram staining. The remaining was used for DNA extraction. PCR assay was performed with universal primers for 16S rDNA gene of bacteria. Performance characteristics of the test were determined. Findings: The PCR method was able to detect bacteria in all 36 culture-positive and in 38 of 64 culture-negative cases showing sensitivity and specificity of 100% and 40.6% respectively. Positive predictive value was 48.6% and negative predictive value 100%, however, Kappa coefficient showed the correlation of the 2 methods to be at 0.33. Conclusion: There are advantages and disadvantages in performance characteristics of the conventional CSF culture and universal CSF 16S rDNA PCR. Therefore, it is recommended to use both methods in clinical practice, particularly in suspicious contaminated samples, with presumable presence of fastidious or slow growing bacteria because of antibiotic consumption. [ABSTRACT FROM AUTHOR]

Objective MicroRNAs (miRNAs) are a class of small non-coding RNAs that play pivotal roles in many biological processes such as regulating skeletal muscle development where alterations in miRNA expression are reported during myogenesis. In this study, we aimed to investigate the impact of predicted miRNAs and their target genes on the myoblast to myocyte differentiation process. Materials and Methods This experimental study was conducted on the C2C12 cell line. Using a bioinformatics approach, miR-214 and miR-135 were selected according to their targets as potential factors in myoblast to myocyte differentiation induced by 3% horse serum. Immunocytochemistry (ICC) was undertaken to confirm the differentiation process and quantitative real-time polymerase chain reaction (PCR) to determine the expression level of miRNAs and their targets. Results During myoblast to myocyte differentiation, miR-214 was significantly down- regulated while miRNA-135, Irs2, Akt2 and Insr were overexpressed during the process. Conclusion miR-214 and miR-135 are potential regulators of myogenesis and are involved in skeletal muscle development through regulating the IRS/PI3K pathway.

Objectives: Multidrug resistance (MDR) is a major obstacle in the successful chemotherapy of ovarian cancer. Inhibition of P-glycoprotein (P-gp), a member of ATP-binding cassette (ABC) transporters, is a well-known strategy to overcome MDR in cancer. The aim of this study was to investigate the efficiency and ability of CRISPR/Cas9 genome editing technology to knockdown ABCB1 gene expression in adriamycin resistant (A2780/ADR) ovarian cancer cell line and evaluate the sensitivity changes to doxorubicin., Materials and Methods: Three single-guide RNAs (sgRNAs) targeting the fourth and fifth exons of human ABCB1 gene were designed in this study. Expression level of ABCB1 was detected using quantitative real time PCR (qRT-PCR) after co-transfection of all three sgRNAs into A2780/ADR cell line and subsequent antibiotic selection. Drug sensitivity to doxorubicin was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay., Results: The results showed that CRISPR/Cas9 system could significantly reduce the expression of P-gp. The dramatic decline in ABCB1 gene expression was associated with increased sensitivity of cells transfected with sgRNAs to doxorubicin., Conclusion: Based on the results of this study, it is concluded that the CRISPR-based systems, used in the present study, effectively down-regulated the target gene and acted as an ideal and cost-effective tool for gene editing of A2780/ADR cell line resulting in restoration of nonmalignant phenotype.

Growing evidence indicates that homocysteine (Hcy) may be involved in the pathophysiology of several neurological disorders including Parkinson's disease. In the present study, the association between blood Hcy concentration and the degree of behavioral symptoms in the 6-hydroxydopamine (6-OHDA)-induced Parkinsonism in rat was evaluated. Total serum Hcy (tHcy) was measured before and 6 weeks after the intracerebral injection of 6-OHDA. Apomorphine-induced rotational test was performed at second, third and sixth weeks after 6-OHDA injection. Subsequently, cell replacement therapy was performed on rats with good rotation score. No correlation between tHcy in before 6-OHDA injection and severity of the rotations after 6-OHDA injection was observed. On the other hand, 6-OHDA treatment significantly decreased tHcy level. However, this reduction was only observed in animals with low degree of rotations and in rats with high number of rotations; tHcy did not change significantly. Furthermore, 10 weeks after cell transplantation, tHcy was significantly lower than that found before therapy if the rats showed good improvement in the degree of rotations. We also examined the effect of different supplements of B vitamins on tHcy before and after 6-OHDA injection. In healthy rats, all kinds of B vitamins and also supplement B6 or B12 alone reduced tHcy. Following 6-OHDA injection, B vitamin supplementation failed to cause remarkable effect. Considering the direct correlation between the severity of rotational behavior and the degree of lesion in the substantia nigra (SN), our data indicate that higher tHcy values can predict higher SN dopaminergic neurodegeneration., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Several lines of evidence show that homocysteine (Hcy) levels are increased in blood and CSF of patients with Parkinson's disease. B vitamins are necessary for Hcy metabolism and their deficiencies cause hyperhomocysteinemia and neurodegeneration. In present study, effect of B vitamin supplementation on the severity of 6-hydroxydopamine (6-OHDA)-induced Parkinsonism was investigated. Rats were nourished with B vitamin supplements from 1 month before of stereotaxic injection of 6-OHDA to the end of experiments. Total serum Hcy was measured at the end of experiments to identify its association with Parkinsonism. Both rotational and rotarod tests revealed that supplementation of folic acid, in a dose dependent manner, attenuates severity of Parkinsonism. Supplement of B complex also had beneficial effect and improved motor performance in rotarod test and decreased biased swings in elevated body swing test but had no effect on the apomorphine-induced rotational behavior. Supplement of B(6) attenuated rotational behavior but had no effect on the rotarod performance and swinging behavior. Supplement of B(12) or combination of folic acid with B(6) and B(12) had no effect on the behavioral symptoms of Parkinsonism. Except one group, the levels of Hcy in other vitamin B treated groups were near to that in control group. Surprisingly, Hcy in group of rats that received high intake of folic acid was significantly higher than that in control group. Our results indicate that high intake of folic acid or B complex provides anti-Parkinsonism effect but it is not mediated by lowering plasma Hcy., (Copyright © 2012 Elsevier B.V. All rights reserved.)