Objectives:To evaluate the performance of GeneXpert MTB/RIF assay for direct diagnosis of pulmonary tuberculosis (PTB).Methods:This is a cross-sectional study conducted between October 2013 and February 2016 at Abbassaia Chest Hospital and Ain Shams University Hospital, Cairo, Egypt. Inclusion criteria were adults between 18 and 60 years with suspected PTB and classified into 5 clinical categories based on their clinical, radiological, and laboratory findings: confirmed TB, probable TB, possible TB, unlikely TB, and not TB. Two sputum samples from each participant were analyzed by GX and the results were compared by conventional culture.Results:In total, 218 participants were enrolled: 71 had confirmed TB; 112, highly probable TB; 20, probable TB; 10, unlikely TB; and 5, no TB. The sensitivity and specificity of the GX assay were 93% and 98.3% respectively. GeneXpert was positive in 93% of confirmed TB and 2.2% of probable TB cases.Conclusions:GeneXpert is a rapid and promising technique with good sensitivity (93%) and specificity (98.3%), but it cannot be used as a standalone PTB diagnostic tool. There is a need for more GX evaluation studies in countries with low TB incidence.

Prior studies have shown that irradiated filarial larvae are developmentally stunted but capable of inducing partial immunity to filariasis in animals. The mechanisms for these effects are poorly understood. Recent studies suggest that intracellular Wolbachia bacteria are necessary for the normal development, reproduction and survival of filarial nematodes. The purpose of this study was to examine the effects of irradiation on Wolbachia in Brugia malayi infective larvae (L3) and on L3 development. The L3 were exposed to 0, 25, 35, 45, 55, 65 or 75 krad of gamma irradiation from a (137) Cesium source and cultured in vitro at 37 degrees C in NCTC/IMDM medium with 10% FCS for 12 days. Irradiation prevented molting of L3 to the L4 stage in a dose-dependent manner. Electron microscopy studies showed that irradiation damaged Wolbachia (25 krad) or cleared them from worm tissues (45 krad). In addition, majority of the irradiated L3s failed to develop the L4 cuticle. Real-time PCR studies showed that irradiation reduced Wolbachia DNA in worm tissues. Parallel in vivo studies confirmed decreased development of irradiated L3 in jirds, with associated effects on Wolbachia. Jirds injected s.c with normal L3 developed antibodies to Wolbachia surface protein (wsp) shortly after the onset of microfilarial patency. In contrast, jirds injected with irradiated L3 did not develop microfilaremia or antibodies to wsp. Additional studies are needed to test the hypothesis that irradiation retards growth and development of filarial L3 by killing Wolbachia.

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Herpes simplex virus type 2 (HSV-2) is a dsDNA virus and it is the causative agent of genital herpes infection. The most important problem of herpes viruses is the reactivation that may lead to recurrent infection. On the other hand, Vesicular stomatitis virus (VSV) is a negative strand RNA virus that can cause many diseases to animals and rarely to human. Excess antiviral drugs use in the treatment of viral infections can induce mutagenicity and cross-resistance so searching for new source of antiviral drugs such as marine actinomycetes is required. A total of 72 Actinomycetes isolated from Qarun Lake governed to El-Fayoum-Egypt were screened for their antimicrobial activities against six bacterial strains, three fungal strains and one yeast strain. All of actinomycetes isolates were assayed for their antimicrobial activities using inhibition zone method and found that 10 isolates were active against bacteria, 3 isolates have activities against fungi and 5 isolates have both antibacterial and antifungal activities. All active isolates were tested for antiviral potentials using Cytopathic Effect (CPE) inhibition assay after determination of safe concentrations of actinomycete filtrates on Vero cells using MTT assay. Vesicular stomatitis virus (VSV) and Herpes simplex virus type 2 (HSV-2), were used as a test viruses. Nine isolates proved antiviral potentials against both viruses. Two isolates coded to Q 3 and B 2 T were selected as the most active isolates against HSV-2 and VSV, respectively and were identified as a genus of Streptomyces. Our result gives conclusion that, marine actinomycetes still considered as a valuable source of many antimicrobial agents and can produce antiviral drugs against both DNA and RNA viruses.

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