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BackgroundSusceptibility testing of herpes simplex virus type 1 (HSV-1) is traditionally performed by a plaque reduction assay (PRA), but this is labor intensive, time consuming and has a manual read out.ObjectivesThe goal of this study was to develop an internally controlled real time PCR-based phenotypical susceptibility test for HSV-1 that is suitable for use in a clinical diagnostic setting.Study designA DNA reduction assay (DRA) was developed and validated on a test panel of 26 well-characterized isolates of varying susceptibility to aciclovir or foscarnet, including low-level resistant isolates. The DRA consisted of pre-culture of a clinical sample for 48 h and subsequent culture in the presence of antivirals for 24 h. Viral DNA concentration in the culture lysates was measured by an internally controlled quantitative real-time HSV-1 PCR and corrected for cell count and lysis by beta-globin PCR. DRA results were compared to results from PRA and sequence analysis.ResultsDRA results were in accordance with PRA results for both aciclovir and foscarnet susceptibility and appeared to have good discriminative value for low-level resistance due to UL30 gene mutations. Although the direct application of DRA in clinical samples appeared not possible, short pre-culture of 48 h was sufficient and ensured results within a clinically relevant time frame of 5 days.ConclusionsDRA is an accurate, rapid and easy to perform phenotypical susceptibility test for HSV-1.  相似文献   
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Dipeptidyl peptidase-4 (DPP4) inhibitors are a novel therapy widespread used in type 2 diabetes mellitus. We describe 3 cases of polyarthritis which delay of appearance strongly suggests a link with DPP4 inhibitors. Three patients presented with bilateral, symmetrical, seronegative polyarthritis after introduction of DPP4 inhibitors (sitagliptine (n = 2) and vildagliptine (n = 1)). Two patients also developed xerostomia and xerostomia, and laboratory test results showed normal values of CRP and erythrocyte sedimentation rate. Joints X-rays were normal. One patient was diagnosed with primary Sjögren’s syndrome and treated with hydroxychloroquine, methotrexate and prednisone, with a poor efficacy. When sitagliptine was stopped, all symptoms disappeared, leading to methotrexate and prednisone discontinuation within a month. There were no immunological abnormalities in the 2 other patients, but a chronic viral hepatitis B was found in one patient. Eventually, discontinuation of DPP4 inhibitors led to resolution of symptoms in 1 and 3 weeks for both patients. DPP4 inhibitors seemed to trigger bilateral, non-erosive, seronegative polyarthritis in our 3 patients. DPP4, also known as CD26, is expressed on many cells including lymphocytes and fibroblasts, and its inhibition may lead to immunomodulating effect as suggested by clinical and in vitro studies.  相似文献   
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Youthful indoor tanning as few as ten sessions can increase the risk of melanoma by two to four times with each additional session adding another 2 % to the risk. Recent research estimates that indoor tanning can be linked to approximately 450,000 cases of skin cancer annually in the USA, Europe, and Australia. Despite these risks, indoor tanning remains popular with adolescents. This study tested the efficacy of a web-based skin cancer prevention intervention designed to reduce indoor tanning motivations in adolescent females. A nationally representative sample of 443 female teens was enrolled from an online panel into a two-arm, parallel group design, randomized controlled trial. Treatment participants received an appearance-focused intervention grounded in established health behavior change models. Controls viewed a teen alcohol prevention website. Outcome variables included willingness and intentions to indoor tan, willingness to sunless tan, and measures of indoor tanning attitudes and beliefs. The intervention decreased willingness and intentions to indoor tan and increased sunless tanning willingness relative to controls. We also examined indirect mechanisms of change through intervening variables (e.g., indoor tanning attitudes, norms, positive and negative expectancies) using the product of coefficient approach. The web-based intervention demonstrated efficacy in changing adolescent indoor tanning motivations and improving their orientation toward healthier alternatives. Results from the intervening variable analyses give guidance to future adolescent skin cancer prevention interventions.  相似文献   
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The current study is an effort to investigate the chemical constituents and antioxidant potential of Cnidoscolous chayamansa McVaugh (Euphorbiacea) root on carbon tetrachloride-induced liver damage. Albino rats were grouped into four: A - D. Groups A and B received 1?mL/kg BW of olive oil and 1?mL/kg body weight (BW) of carbon tetrachloride (CCl4), respectively, for 8 days while those in C and D received 1?mL/ kg BW each of CCl4 and 500 and 1000?mg/kg BW of aqueous extract of C. chayamansa root, respectively, for the same period. Chemical analysis of the plant root revealed the presence of tannins, phenolics, flavonoids, saponins, Fe, Zn, Mg, Ca, vitamins A and C. Administration of CCl4 resulted in significant increase (P?<0.05) in liver malondialdehyde concentration while the activities of liver alkaline phosphatase, superoxide dismutase, glutathione peroxidase and catalase were significantly reduced (P?<0.05). Simultaneous administration of CCl4 and the plant extract at 500 and 1000?mg/kg BW produced values of these biochemical parameters that compared favourably with the control (P?>0.05) in addition to increasing superoxide dismutase activity in the liver (P?<0.05). We conclude that aqueous extract of C. chayamansa root possessed antioxidant activity and protected the hepatocyte against CCl4-induced damage. The antioxidant activity of the plant may be due to its chemical constituents.  相似文献   
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