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Type 2 diabetes mellitus (T2DM) is a major health problem, worldwide, that is associated with increased morbidity and mortality. Several randomized controlled clinical trials (RCTs) have investigated the effect of nettle (Urtica dioica) supplementation on markers of glycemic status in patients with T2DM, with conflicting results. Therefore, the present study assessed the effect of nettle on some glycemic parameters in patients with T2DM. A comprehensive search was conducted in PubMed, Scopus, Cochrane Library, and Web of Science, from database inception up to June 2019, to identify RCTs investigating the effect of nettle supplementation on glycemic markers, including fasting blood sugar (FBS) concentrations, insulin levels, homeostasis model assessment‐estimated insulin resistance index, and glycosylated hemoglobin percentage in adults with T2DM. The Cochrane Collaboration tool was used to assess the methodological quality of the included studies. Results of this meta‐analysis were reported based on the random effects model. Eight RCTs, comprising 401 participants, were included in the present systematic review and meta‐analysis. Based on the Cochrane Collaboration risk of bias tool, five studies were considered as good quality, one was fair, and two studies were poor, respectively. The results of the meta‐analysis revealed a significant reduction in FBS concentrations (weighted mean difference [WMD]: ?18.01 mg/dl, 95% confidence interval [CI]: ?30.04 to ?5.97, p < .001, I2 = 94.6%) following nettle supplementation. However, no significant reduction was observed in insulin levels (WMD: 0.83 Hedges' g, 95% CI: ?0.26 to 1.92, p = .13, I2 = 89.4%), homeostasis model assessment‐estimated insulin resistance index (WMD: ?0.22, 95% CI: ?0.83 to 0.40, p = .49, I2 = 69.2%), or glycosylated hemoglobin percentage (WMD: ?0.77%, 95% CI: ?1.77 to 0.22, p = .12, I2 = 83.0%). The findings of the present study suggest that nettle supplementation may be effective in controlling FBS for T2DM patients. However, further studies are needed to confirm the veracity of these results.  相似文献   
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Dentinal hypersensitivity is a painful condition that occurs following periodontal treatment. Many treatment alternatives have been considered for this problem, including treatments with laser and dentinal adhesives. This study compared the sealing ability of Nd:YAG laser versus a new resin in scanning electron microscopy (SEM) micrographs. Ten human premolars were sectioned yielding 30 specimens of each premolar, which were randomly divided into three groups. The laser group was irradiated by Nd:YAG laser (1 W, 10 Hz, 60 s), the resin group was treated with the new Seal & Protect resin according to the manufacturer’s instructions, and the third group served as the control group and did not receive any interventions. After preparation and gold coating of the samples, they were photographed by SEM at two magnifications (1500× and 4000×). The number and diameter (μm) of the dentinal tubules were recorded in selected fields, and analysis of variance (ANOVA) and Tukey tests were used to determine significant differences between groups. The ANOVA results revealed significant differences in both the mean number (P < 0.001) and diameter (P < 0.05) among the three groups. Further statistical analysis showed a significant difference between the laser group and the resin group in both outcome measures (P < 0.05). Thus, both Nd:YAG laser and the new resin reduced the number and diameter of open dentinal tubules, a result that also explains the desensitization mechanism of these interventions. We further conclude that application of the new resin is more effective than Nd:YAG laser in minimizing the number and diameter of exposed dentinal tubules.  相似文献   
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Abed Y  Baz M  Boivin G 《Antiviral therapy》2006,11(8):971-976
Subtype-specific neuraminidase (NA) mutations conferring resistance to NA inhibitors (NAIs) have been reported during in vitro passages and in clinic. In this study, we evaluated the impact of various NA mutations (E119A/G/V, H274Y, R292K and N294S) on the susceptibility profiles to different NAIs (oseltamivir, zanamivir and peramivir) using recombinant NA proteins of influenza A/WSN/33 (H1N1) and A/Sydney/5/97-like (H3N2) viruses. In the Nl subtype, the E119V mutation conferred cross-resistance to oseltamivir, zanamivir and peramivir [1,727-2,144 and 5,050-fold increase in IC50 values compared with wild-type (WT)] whereas only oseltamivir-resistance (1,028-fold increase in IC50) was conferred by the same mutation in the N2 subtype. The N294S mutation conferred resistance to oseltamivir in both the NI and N2 subtypes (197- and 1,879-fold increase in IC50 values, respectively) whereas the H274Y mutation conferred resistance to oseltamivir (754-fold increase) and peramivir (260-fold increase) in the N1 subtype only. The virulence of reverse genetics-rescued A/WSN/33 viruses harbouring H274Y and N294S NA mutations was investigated in Balb/c mice. The WT and H274Y recombinants had identical LD50 values (103 PFUs) and generated similar viral lung titres, whereas a higher LD50 (10 PFUs) and a 1-log decrease in viral lung titres were obtained with the N294S mutant. This study shows that some NA mutations at framework residues may confer resistance to one or three NAIs depending on the viral subtype. It suggests that certain drug-resistant NA mutants may still be virulent although additional studies using clinical isolates are needed to confirm our results.  相似文献   
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In this paper we analyze a fibrosis scoring method based on measurement of the fibrillar collagen area from second harmonic generation (SHG) microscopy images of unstained histological slices from human liver biopsies. The study is conducted on a cohort of one hundred chronic hepatitis C patients with intermediate to strong Metavir and Ishak stages of liver fibrosis. We highlight a key parameter of our scoring method to discriminate between high and low fibrosis stages. Moreover, according to the intensity histograms of the SHG images and simple mathematical arguments, we show that our area-based method is equivalent to an intensity-based method, despite saturation of the images. Finally we propose an improvement of our scoring method using very simple image processing tools.OCIS codes: (180.4315) Nonlinear microscopy, (170.1610) Clinical applications, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine, (110.2960) Image analysis  相似文献   
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ObjectiveTo assess serum vitamin D status and its relations to other biochemical parameters in type 2 diabetic patients from Gaza Strip.Materials and methodsThis case-control study included 58 type 2 diabetic patients as well as 58 non-diabetic controls. Patients and controls were matched for age and gender. Data were obtained from questionnaire interview, and biochemical analysis of blood samples.ResultsSerum vitamin D was significantly lower in diabetic patients compared to non-diabetic controls (25.9 ± 11.0 versus 34.6 ± 13.8 ng/dl, % difference = 28.8%, P < 0.001). The number of patients having vitamin D deficient, insufficient and sufficient were 6 (10.4%), 35 (60.3%) and 17 (29.3%) compared to controls of 3 (5.2%), 16 (27.6%) and 39 (67.2%), respectively (χ2 = 14.672, P < 0.001). Serum glucose, glycated hemoglobin (HbA1c), serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and triglycerides were significantly higher in patients than in controls whereas serum insulin, high density lipoprotein cholesterol (HDL-C) and calcium were significantly lower in patients. Serum vitamin D showed significant negative correlations with HbA1c (r = ? 0.186, P = 0.046), ALT (r = ? 192, P = 0.040) and AST (r = ? 0.188, P = 0.044) whereas significant positive correlations were found with HDL-C (r = 0.188, P = 0.044) and calcium (r = 0.239, P = 0.010).ConclusionThe significant negative and positive correlations of vitamin D with HbA1c and calcium, respectively suggests that vitamin D supplementation would be of potential therapeutic value in clinical settings for controlling of type 2 diabetes and more importantly its complications. However, a well-designed clinical trials are needed to define the contribution of vitamin D status and therapy in the global diabetes problem.  相似文献   
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