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31.
Ferulago carduchorum (Apiaceae) is an endemic plant of Iran. From the hexane and ethyl acetate extracts of F. carduchorum seven coumarins, one flavonoid and one steroid were isolated using column chromatography with silica gel and Sephadex LH20 as the stationary phases. Antimicrobial activity of the isolated compounds was examined by a broth microdilution method. Acetylcholinesterase (AChE) inhibitory activity of isolated coumarins was also investigated. The isolated compounds were identified as suberosin, suberenol, bergapten, xanthotoxin, isopimpinellin, prantschimgin, β-sitosterol and hesperetin by comparison of their NMR and MS spectral data with those reported in the literature. Evaluation of the minimum inhibitory concentration (MIC) for each compound showed that hesperetin (flavonoid) was the most potent antimicrobial agent against a gram-positive bacterium (Staphylococcus aureus) and among the coumarins, bergapten had the best activity against S. aureus and Candida albicans. All coumarins inhibited AchE enzyme, in which xanthotoxin showed the most inhibitory among them (IC50 = 39.64 µM). Our results indicate that isolated coumarins are effective against the tested bacterial strains and have AchE inhibitory activity suggesting their potential for commercial applications.  相似文献   
32.
The aim of our study is to build a framework for a better understanding of high-grade glioma (HGG) prognostic-related biomarkers. Whole-genome gene expression microarray was performed to identify differently expressed genes between HGGs and low-grade diffuse gliomas. Several machine learning algorithms were used to filter prognostic-related genes. One hundred ninety-three HGG patients after surgical resection were selected for survival analysis. Immunohistochemistry were performed on these tumor samples to analyze IDH1 mutation status and protein expression of WEE1. qRT-PCR, western blotting, transwell assays, and scratch wound healing assays were performed to evaluate the effect of WEE1 knockdown or overexpression in HGG cells. Three prognostic-related genes (WEE1, IGF2PB3, and EMP3) were demonstrated to separate HGG patients into two different survival subgroups. The area under receiver operating characteristic curve of WEE1 was higher than that of IGF2BP3, EMP3, age, IDH status, 1p/19q status, and MGMT promoter status. WEE1 was an independent covariate compared with IDH status, age, and WHO grade. Knockdown or overexpression of WEE1 can inhibit or promote migration and invasion in U251 and U87 cell lines. WEE1, EMP3, and IGF2BP3 are reliable prognostic-related genes at the mRNA level. WEE1 is an independent prognostic biomarker in survival analysis and has potential diagnostic value for HGG patients. WEE1 can induce HGG cell migration and invasion in vitro.  相似文献   
33.
Neural stem cells are self-renewing, multipotent cells that can be found in subventricular (SVZ) and subgranular (SGZ) zones of the brain. These zones are susceptible to irradiation-induced apoptosis and oxidative stress. Melatonin (MLT) is a natural protector of neural cells against toxicity. The aim of this study was to evaluate the effects of MLT as a radio-protective material effective in reducing tissue lesions in the SVZ of the brain and changing local apoptotic potential in rats. Twenty-five Gray irradiation was applied on adult rat brain for this study. One hour before irradiation, 100 mg/kg/IP MLT was injected, and 6 h later, the animals were sacrificed. The antioxidant enzymes and MDA activity levels were measured post-sacrifice. Also, the expression level of Nestin and caspase 3 were studied by immunohistochemistry. Spectrophotometric analysis showed significant increases in the amount of malondialdehyde (MDA) levels in the irradiation-exposed (RAD) group compared to that of the control (Co) group (P < 0.05). Pre-treatment with MLT (100 mg/kg) ameliorates the harmful effects of the aforementioned 25 Gy irradiation by increasing antioxidant enzyme activity and decreasing MDA levels. A significant reduction in apoptotic cells was observed in rats treated with MLT 1 h before exposure (P < 0.001). Nestin-positive cells were also reduced in the RAD group (P < 0.001). Our results confirm the anti-apoptotic and antioxidant role of MLT. The MLT concentration used may serve as a threshold for significant protection against 25 Gy gamma irradiations on neural stem cells in SVZ.  相似文献   
34.

Introduction

The Glasgow Coma Scale (GCS) has some limitations when evaluating the unconscious patient. This study aims to validate the Persian version of the FOUR (Full Outline of Unresponsiveness) score as a proposed substitute.

Methods

Two nurses, two nursing students, and two physicians scored the prepared Persian version of the FOUR and GCS in 84 patients with acute brain injury. The inter-rater agreement for the FOUR and the GCS scores was evaluated by the weighted kappa (κ w). The outcome prediction power of the scales was assessed by the area under the curve (AUC) in the ROC curve.

Results

The inter-rater agreement of the FOUR was excellent (κ w = 0.923, 95 % CI, 0.874–0.971) and comparable with the one of the GCS (κ w = 0.938, 95 % CI, 0.889–0.987). The area under the curve (AUC) for predicting in-hospital mortality (modified Rankin Scale: 6) was 0.835 for the FOUR (95 % CI, 0.739–0.907) and 0.772 for the GCS (95 % CI, 0.668–0.856) (P = 0.01). AUC for predicting poor outcome (modified Rankin Scale: 3–6) for the total FOUR score was 0.983 (95 % CI, 0.928–0.999), which is comparable with 0.987 for the total GCS score (95 % CI, 0.934–1.000).

Conclusions

The researchers conclude that the Persian version of the FOUR score is a reliable and valid scale to assess unconscious patients with traumatic brain injury and can be substituted for the GCS.
  相似文献   
35.
Thyroid cancer (TC) is the mainly frequent endocrine cancer by different incidence rate in worldwide. However, early prediction of  this cancer is still challenging due to the unclear pathogenicity. In this study with the aid of systems biology approach, performed a holistic study on GSE65144 dataset containing anaplastic thyroid carcinoma tissues. Co-expression network analysis by WGCNA suggested that highly preserved turquoise module with 1,480 genes was significantly correlated to TC. Most of the top 54 hub-genes of this module are functionality correlated to thyroid hormone generation (GO:0006590). Of these 54 hub-genes, FOXE1 has been reported previously to contain mutation asosiated to TC and chosen for experimental validation step. To this end, we conducted a case-control study including 81 TC patients and 165 controls individuals to evaluate the effects of FOXE1 functional polymorphisms (rs1867277) on the development of TC in Sistan and Balouchestan province of Iran. The polymorphisms of FOXE1 gene (rs1867277) assessed by tetra-ARMS PCR technique. Homozygous (GG) and (AA) variant of rs1867277 polymorphism were detected in 26 (32.1%) and 15 (18.5 %) of TC patients, and 66 (40.0%), and 15 (9.1%) in controls, respectively (p-value= 0.03, OR= 2.53). The A allele frequency was 70 (43.2%) in TC patients and 114 (34.5%) in controls (p-value= 0.06, OR= 1.44). Overall, our results suggested that FOXE1 gene could be used as a prognostic marker in TC and also provides information related to FOXE1 functional polymorphisms (rs1867277) in Sistan and Balouchestan province of Iran.  相似文献   
36.
Objectives: Pediatric asthma is heterogeneous with phenotypes that reflect differing underlying inflammation and pathophysiology. Little is known about the national prevalence of certain obesity- and allergy-related asthma phenotypes or associated characteristics. We therefore assessed the national prevalence, risk factors, and caregiver-reported severity of four asthma phenotypes: not-allergic-not-obese, allergic-not-obese, obese-not-allergic, and allergic-and-obese. Methods: We analyzed data from the 2007–2008 National Survey of Children's Health (NSCH) of 10–17 year-olds with caregiver-reported asthma. We described sociodemographic and health risk factors of each phenotype and then applied logistic and ordinal regression models to identify associated risk factors and level of severity of the phenotypes. Results: Among 4427 children with asthma in this NSCH cohort, the association between race and phenotype was statistically significant (p < 0.0001); white children with asthma were most likely to have allergic-not-obese asthma while black and Hispanic children with asthma were most likely to have the obese-nonallergic phenotype (p < 0.001). Attention-deficit disorder/attention-deficit hyperactivity disorder was more likely to be present in allergic-not-obese children (odds ratio (OR) 1.50, confidence interval (CI) 1.14–1.98, p = 0.004). The phenotype with the highest risk for more severe compared to mild asthma was the obese-and-allergic asthma phenotype (OR 3.34, CI 2.23–5.01, p < 0.001). Conclusions: Allergic-not-obese asthma comprised half of our studied asthma phenotypes, while obesity-related asthma (with or without allergic components) comprised one-fifth of asthma phenotypes in this cohort representative of the US population. Children with both obese and allergic asthma are most likely to have severe asthma. Future management of childhood asthma might consider more tailoring of treatment and management plans based upon different childhood asthma phenotypes.  相似文献   
37.
While various tools such as the International Prognostic Index (IPI) and its derivatives exist for risk-stratification of diffuse large B-cell lymphoma (DLBCL) at diagnosis, patient and disease characteristics capable of predicting outcome after high-dose chemotherapy followed by autologous stem cell transplantation (HDC/ASCT) are not clearly defined. We retrospectively analyzed medical records of 111 DLBCL patients (78 relapsed and 33 refractory) who underwent HDC/ASCT at our institution from 2010-2015. After a median follow-up time of 4.6 years (interquartile range [IQR] 2.2-8.1), the likelihood of 5-year progression-free survival (PFS) was 62.2% (95% CI, 53.4%-72.4%) and the likelihood of 5-year overall survival (OS) was 68.9% (95% CI, 60.7%-78.2%). More than three chemotherapy regimens prior to ASCT was the only variable associated with lower likelihood of PFS (P = .004) and OS (P = 0.026). Male gender and high IPI score at time of ASCT were also associated with lower likelihood of PFS (P = .043; P = .013). NCCN IPI and age-adjusted IPI at time of ASCT were not predictive of outcome following ASCT. Patients with refractory and relapsed disease had similar outcomes post-ASCT (P = .207 for PFS, P = .073 for OS).  相似文献   
38.
In this study, novel acridone‐1,2,4‐oxadiazole‐1,2,3‐triazole hybrids were designed, synthesized, and evaluated for their acetylcholinesterase and butyrylcholinesterase inhibitory activity. Among various synthesized compounds, 10‐((1‐((3‐(4‐methoxyphenyl)‐1,2,4‐oxadiazol‐5‐yl)methyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)acridin‐9(10H)‐one 10b showed the most potent anti‐acetylcholinesterase activity (IC50 = 11.55 μm ) being as potent as rivastigmine. Also docking outcomes were in good agreement with in vitro results confirming the dual binding inhibitory activity of compound 10b .  相似文献   
39.
This report illustrates the applications of Asymmetric Sharpless Aminohydroxylation (ASAH) in the stereoselective synthesis of vicinal amino alcohols as important intermediates in the total synthesis of complex molecules and natural products with significant biological activities. The ASHA allows the regio- syn-selective synthesis of 1,2-amino alcohols via reaction of alkenes with salts of N-halosulfonamides, -amides and -carbamates employing osmium tetroxide (OsO4) as an efficient catalyst. In this reaction, chirality is induced via the addition of dihydroquinine- and dihydroquinidine as derived chiral ligands.

This work shows applications of Asymmetric Sharpless Aminohydroxylation (ASAH) in the stereoselective synthesis of vicinal amino alcohols as important intermediates in the total synthesis of complex molecules and natural products with significant biological activities.  相似文献   
40.
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