Fabrication and evaluation of electrospun polyacrylonitrile/silver nanofiber membranes for air filtration and antibacterial activity.

Particulate matter and airborne microorganisms are two of the most severe indoor air problems due to their significant risks to human health. Comprehensive research on air filtration with good filtration performance for fine particles and antibacterial function is essential. In this study, after some experimentations and optimization of conditions, polyacrylonitrile (PAN) 10-1% silver nanoparticles (AgNPs) membranes with suitable morphology and uniform diameter distribution are fabricated by an electrospinning method. These electrospun mats exhibited antibacterial activity toward Staphylococcus aureus (Gram-positive bacteria) and Escherichia coli (Gram-negative bacteria). With its small pore size, high porosity, the high specific surface area of 42 m2/g, and robust mechanical strength of 7.14 MPa properties, the resultant PAN10%-1%Ag membranes exhibit high filtration efficiency of 99.27%, the low pressure drop of 33 Pa, and higher quality factor compared to the two standard commercial masks including, the three-ply surgical mask and the respirator face mask. After 24 h of the filtration process in a simulated living environment, the obtained air filter still displayed a high filtration efficiency and a less pressure drop variation. In addition, the R 2 value was 0.99, which indicates that the calculation results are in good agreement with the measured results. The fabrication of PAN-Ag membranes will have broad applications, including face masks, indoor air filtration and clean room.

Molecular Analysis of Ganciclovir-Resistant Cytomegalovirus in Renal Transplant Recipients with High Viral Load.

BACKGROUND: Gancyclovir-resistant (GanR) cytomegalovirus (CMV) remains an issue, especially in solid organ transplant (SOT) recipients. Some mutations in UL54 and UL97 confer this resistance. Long-lasting high-dose drug exposure, high viral load, together with lack of sufficient compliance with treatment may account for these mutations. The aim of this study was to detect UL97 and UL54 putative mutations conferring ganciclovir-resistance in renal organ transplant recipients with high CMV load. METHODS: In this cross-sectional study, 58 serum samples were collected from renal transplant recipients who had referred to three hospitals in Tehran from January 2014 to June 2015. Specific criteria such as CMV syndrome, presence of CMV in blood and organ dysfunction were considered. Then, they were tested for viral load in their early fourth month of intravenous ganciclovir treatment. Fifty cases revealing more than 200 copies/mL were analyzed for mutations. Two fragments of UL54 and Ul97 genes were amplified and sequenced bidirectionally. Sequence alignment and statistical analysis were performed by Mutation Surveyor software and t-test respectively. RESULTS: A significant difference was observed in viral load between seronegative and seropositive recipients (P = 0.036). The most frequent mutation was related to D605E in UL97 gene with the rate of 25%. Regardless of viral load, neither putative mutation nor simultaneous mutation was detected in either UL97 and UL54 regions. CONCLUSION: In spite of high viral load and persistence of symptoms, our population study did not reveal putative mutations. Hence, the direct relationship between the presence of high quantity of CMV and the occurrence of putative mutation cannot be considered. Non-putative gancyclovir resistant mutations and prolonged drug exposure may have a role in these manifestations.

Angled Screw Channel: An Alternative to Cemented Single-Implant Restorations--Three Clinical Examples.

This article presents three cases of single labially tilted implants restored with screw-retained single crowns. Individualized abutments with an angled screw channel were used to avoid an unesthetic vestibular access channel. This individualized abutment allows the dentist and dental technician to use the screw-retained restorations where a cemented reconstruction would otherwise have been needed.

Efficient diagnosis and treatment follow-up of human brucellosis by a novel quantitative TaqMan real-time PCR assay: a human clinical survey.

Rapid and effective diagnosis of brucellosis is a challenge for clinicians. Even when diagnosis is on time and therapy is initiated, meticulous follow-up appointments are crucial for ensuring the efficacy of the treatment. Due to shortcomings of serological methods, molecular diagnosis, especially real-time PCR, is becoming a main approach in laboratory diagnostics. Thus, the development of efficient procedures and standardization of the PCR tests will have a great impact on the precise detection and quantification of bacterial DNA loads, which is valuable for the medical management of brucellosis patients. We developed a new TaqMan real-time PCR directed to bcsp31, a shared gene of the brucellae. The bcsp31 gene fragment was cloned into pJET1.2. Recombinant pJET1.2-bcsp31 was linearized by HindIII digestion, and the product was used for the preparation of a standard curve. A panel of Brucella spp. and non-Brucella pathogens was tested. No bacterial genomes other than those of the brucellae were detected. According to the results, specificity of the method was 100%. In a clinical assessment, the positive-control group comprised 37 patients with microbiologically confirmed brucellosis, and 25 healthy individuals served as the negative-control group. By the end of the treatment period, there was a significant decrease in the DNA load of the 37 brucellosis patients, which persisted for the 4 weeks of monitoring after treatment, suggesting that our proposed method is an efficient monitoring tool. Serum samples prior to any treatment were collected from the 25 serologically suspicious patients and assessed by our method; 72% of these patients tested positive for brucellosis.

Adenosine induces cell cycle arrest and apoptosis via cyclinD1/Cdk4 and Bcl-2/Bax pathways in human ovarian cancer cell line OVCAR-3.

Adenosine is a regulatory molecule with widespread physiological effects in almost every cells and acts as a potent regulator of cell growth. Adenosine has been shown to inhibit cell growth and induce apoptosis in the several cancer cells via caspase activation and Bcl-2/Bax pathway. The present study was designed to understand the mechanism underlying adenosine-induced apoptosis in the OVCAR-3 human ovarian cancer cells. MTT viability, BrdU and cell counting assays were used to study the cell proliferation effect of adenosine in presence of adenosine deaminase inhibitor and the nucleoside transporter inhibitor. Cell cycle analysis, propidium iodide and annexin V staining, caspase-3 activity assay, cyclinD1, Cdk4, Bcl-2 and Bax protein expressions were assessed to detect apoptosis. Adenosine significantly inhibited cell proliferation in a concentration-dependent manner in OVCAR-3 cell line. Adenosine induced cell cycle arrest in G0/G1 phase via Cdk4/cyclinD1-mediated pathway. Adenosine induced apoptosis, which was determined by Annexin V-FITC staining and increased sub-G1 population. Moreover, down-regulation of Bcl-2 protein expression, up-regulation of Bax protein expression and activation of caspase-3 were observed in response to adenosine treatment. The results of this study suggest that extracellular adenosine induced G1 cell cycle arrest and apoptosis in ovarian cancer cells via cyclinD1/ Cdk4 and Bcl-2/Bax pathways and caspase-3 activation. These data might suggest that adenosine could be used as an agent for the treatment of ovarian cancer.