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81.
Abstract Effects of hexaflumuron at 10% lethal concentration (LC10) and LC25 on development and reproduction parameters of the diamondback moth, Plutella xylostella (Linnaeus, 1753) (Lep.: Yponomeutidae) were investigated. Estimated LC50, LC10 and LC25 values of leaf dip bioassay of hexaflumuron on the third instar larvae of the P. xylostella were 1.48, 0.59 and 0.91 mg/L, respectively. Hexaflumuron decreased pupal weight in the parent generation at sublethal concentrations but in the offspring generation, this effect was not observed. Sublethal concentrations increased egg, first and second larval instar and pupa developmental time and shortened life span of adults, but did not change the third and fourth larval instars and pre‐pupa developmental period. Also fecundity of females reduced significantly but hatchability of treatments and control were similar. Survival rate of pre‐adult stages declined significantly at LC25 concentration. Reproduction parameters such as reproductive rate (R0) and intrinsic rate of increase in sublethal concentrations were significantly lower compared with control, but gross reproduction rate (GRR) at the LC10 concentration was increased and it could be hormoligosis. Also hexaflumuron significantly increased doubling time (Dt). We conclude that the sublethal effects of hexaflumuron might exhibit significant effects on the population dynamics of P. xylostella.  相似文献   
82.
Different signaling pathways are implicated in proliferation and differentiation of stem cells. Bone Morphogenesis Pathway (BMP) signaling was known to display an important function in osteogenic and adipogenic differentiation of mesenchymal stem cells (MSCs). In the present study, the authors investigated whether blocking BMP signaling was associated with down regulation of Nestin expression as neural stem cell marker in peripheral blood derived mesenchymal stem cells (PB-MSCs). At first, MSCs were isolated from peripheral blood by plastic adherent ability and flow cytometry analysis. After reaching the confluence, the cells were treated with medium containing Noggin as antagonist of BMP signaling upon 8 days. Real time PCR analysis indicated that the expression of Nestin was diminished in PB-MSCs by attenuating BMP signaling. The obtained results suggested that BMP signaling might have a regulatory function on the Nestin expression in mesenchymal stem cells.  相似文献   
83.
In the present study, the potential of transdermal nanoemulsion gel of selegiline hydrochloride for the treatment of Parkinson’s disease was investigated. Water-in-oil nanoemulsions were developed by comparing low- and high-energy methods and were subjected to thermodynamic stability tests, in vitro permeation, and characterization studies. In vitro studies indicated that components of nanoemulsion acted as permeation enhancers with highest flux of 3.531 ± 1.94 μg/cm2/h from nanoemulsion SB6 containing 0.5 mg selegiline hydrochloride, 3% distilled water, 21% S mix (Span 85, Tween 80, PEG 400), and 76% isopropyl myristate by weight. SB6 with the least droplet size of 183.4 ± 0.35 nm, polydispersity index of 0.42 ± 0.06 with pH of 5.9 ± 0.32 and viscosity of 22.42 ± 0.14 cps was converted to nanoemulsion gel NEGS4 (viscosity = 22,200 ± 400 cps) by addition of Viscup160® for ease of application and evaluated for permeation, safety, and pharmacokinetic profile in Wistar rats. It provided enhancement ratio 3.69 times greater than conventional gel. NEGS4 showed 6.56 and 5.53 times increase in bioavailability in comparison to tablet and conventional gel, respectively, along with sustained effect. Therefore, the developed water-in-oil nanoemulsion gel promises to be an effective vehicle for transdermal delivery of selegiline hydrochloride.  相似文献   
84.
BackgroundPhysicians are considered to be a high-risk population for a poor quality of life (QoL), but few studies of lifestyle factors include the QoL among them.ObjectivesThis study aimed to investigate the relationship between lifestyle factors and a positive QoL among primary health care (PHC) physicians.MethodsA cross-sectional study was conducted at 20 primary healthcare centers in Madinah, Saudi Arabia. A self-administered questionnaire was used, including sociodemographic characteristics, lifestyle data, and the short version of the World Health Organization Quality of Life questionnaire. Appropriate statistical analyses were used, including multivariate logistic regression models.ResultsThe response rate was 85.7% (72/84) physicians. The mean score of the total QoL and its four studied domains (physical, psychological, social, and environmental) was relatively high, with no statistically significant difference between the consultants and general practitioners. The positive total QoL in this study was significantly lower among physicians with obesity (OR = 0.55, 95%CI = 0.25–0.97), those using butter and animal fat for cooking (OR = 0.10, 95%CI = 0.02–0.81), and those eating meals out > 3 times per week (OR = 0.30, 95%CI = 0.10–0.90). Although non-significant, vegetable consumption and a high level of physical activity were associated with a positive QoL, with adjusted ORs of 2.5 (95%CI = 0.82–7.58) and 1.5 (95%CI = 0.33–6.65), respectively.ConclusionThe findings indicate a relatively good QoL among the participating physicians; however, a lower QoL was associated with unhealthy lifestyle factors. QoL was significantly associated with obesity, cooking practices, and eating meals from restaurants.  相似文献   
85.
DNA vaccines consisted of tumor-associated antigen (TAA) are well suited for immunotherapy against tumor. The construct can contain TAA fused to an appropriate molecule (biologic adjuvant) to improve the efficacy of anti-tumor immune response. Heat shock protein 70 (HSP70) has been shown to be an excellent candidate, capable of cross-priming TAA by antigen presenting cells leading to a robust T-cell response. However, the relationship between strong T-cell responses and tumor rejection is not always mutually exclusive, for which TAA loss or activation of suppressive mechanisms may occur. HSP70 fused to downstream of Her2/neu as DNA vaccine has been shown to be efficient against Her2-expressing tumors. In this study, we examined if N-terminally fusion of Her2/neu to HSP70 could also improve efficiency of Her2/neu DNA vaccine. Therefore, mice with an established Her2/neu expressing tumor were immunized with DNA vaccine consisting of extracellular and trans-membrane domain (EC+TM) of rat Her2/neu alone or N-terminally fused to HSP70 and immune response was evaluated. Administration of rat Her2/neu led to partial control of tumor progression. Surprisingly, fusion of HSP70 to N-terminal of rat Her2/neu led to tumor progression. Our result proposes that fusion direction of biologic adjuvant is an important consideration when Her2/neu is used.  相似文献   
86.
Transmissible spongiform encephalopathies (TSEs) are caused by the accumulation of the abnormal prion protein scrapie (PrPSc). Prion protein aggregation, misfolding, and cytotoxicity in the brain are the major causes of neuronal dysfunction and ultimate neurodegeneration in all TSEs. Parkin, an E3 ubiquitin ligase, has been studied extensively in all major protein misfolding aggregating diseases, especially Parkinson’s disease and Alzheimer’s disease, but the role of parkin in TSEs remains unknown. Here we investigated the role of parkin in a prion disease cell model in which neuroblastoma2a (N2a) cells were treated with prion peptide PrP106–126. We observed a gradual decrease in the soluble parkin level upon treatment with PrP106–126 in a time-dependent manner. Furthermore, endogenous parkin colocalized with FITC-tagged prion fragment106–126. Overexpression of parkin in N2a cells via transfection repressed apoptosis by enhancing autophagy. Parkin-overexpressing cells also showed reductions in apoptotic BAX translocation to the mitochondria and cytochrome c release to the cytosol, which ultimately inhibited activation of proapoptotic caspases. Taken together, our findings reveal a parkin-mediated cytoprotective mechanism against PrP106–126 toxicity, which is a novel potential therapeutic target for treating prion diseases.  相似文献   
87.
88.
Treatment of Cutaneous leishmaniasis (CL) is based on using antimoniate derivatives; patients’ compliance for systemic injections is low due to the pain and systemic complications. In this randomized open trial, the efficacy of intra-lesional (IL) injections of meglumine antimoniate (MA) once a week vs. twice a week in the treatment of Anthrpoponothic CL caused by L. tropica was studied. Eligible volunteer patients were selected according to inclusion/exclusion criteria. The included patients were randomly allocated to receive IL-MA injections once a week or twice a week. The primary outcome was set as complete healing of the lesion(s), and defined as complete re-epithelialization and absence of induration in the lesions. A total of 180 parasitologicaly proven CL patients caused by L. tropica were recruited, 90 patients were treated with weekly IL-MA and 90 patients received IL-MA twice a week. The complete cure was 87.9% vs. 89.2% in the group received weekly and twice a week IL-MA injections, respectively (P = 0.808). Patients’ compliance was acceptable and side effects were limited to a few local allergic reactions to MA. Median time to healing was significantly shorter in patients who received IL-MA twice a week (median ± SE) 37±3.8, (CI: 29.6–44.4) days compared to whom received IL-MA once a week 60±2.3, (CI: 55.6–64.5) days (P< 0.001), however the number of injections was higher in group who received IL-MA twice a week (12 vs. 9 injections). In conclusion, the rate of cure in the group of CL patients with IL-MA twice a week was not significantly different from the group who received IL-MA once a week shorten, but the duration of healing was shorter in the group who received IL-MA twice a week while the group received more injections so is recommended to use IL-MA once a week due to the fact the compliance is acceptable with limited side effects.Clinical Trial Registration: IRCT20081130001475N13; https://en.irct.ir/.  相似文献   
89.
A butter-enriched high-fat diet changes lipid metabolism, resulting in fat storage, hyperlipidemia and obesity. Effects of cinnamon powder were investigated in butter-fed mice. 40 Swiss Albino mice, aged 28 to 30 days, were randomly assigned into two groups. Group A was an untreated control group (n = 8) and another group (n = 32) was a butter-treated group fed 10% butter. In the fifth week, mice of the butter-fed group were further divided into four equal groups: B, C, D, and E (n = 8), fed 10% butter with cinnamon 200 mg, 400 mg, and 600 mg powder per liter drinking water, respectively for 10 weeks. The butter-fed group was gained the most weight. Cinnamon supplementation significantly normalized weight gain and had no harmful effects on hematological parameters. Butter supplementation significantly increased total cholesterol (TC), triglycerides, and LDL cholesterol (LDL-c) whereas, cinnamon powder significantly reduced TC, LDL-c and glucose levels. In butter-fed mice, a significant increase was observed in the liver enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels with subsequent fat deposition in the liver. Excitingly, these enzymes were decreased and no fat depositions were observed in the liver of cinnamon-treated mice. Applying different concentrations of cinnamon powder improved the lipid profile in butter-fed female albino mice.  相似文献   
90.
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