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91.
92.
Tumour necrosis factor alpha (TNF‐α) has an important role in inflammatory response. Alterations in the regulation of TNF‐α have been implicated in a variety of inflammatory disorders, including Inflammatory bowel disease (IBD). Indeed, a common treatment for IBD is the use of TNF‐α inhibitors. Polymorphisms in the TNF‐α promoter region are known to affect the level of gene expression. Our aim was to investigate the influence of these single nucleotide polymorphisms (SNPs) in TNF‐α promoter gene play in the risk of IBD in a Spanish population and their individual response to anti‐TNF‐α treatment. DNA samples from patients with IBD and controls were screened for TNF‐α ?238G/A (rs361525) and ?308G/A (rs1800629) SNPs by PCR‐SSOP using a microbeads luminex assay and compared with response to TNF‐α inhibitors. There were not statistical differences in ?238G/A and ?308G/A allele and genotype frequencies between patients. However, we found an increased frequency of ?308A allele and ?308GA genotype in these nonresponders patients to TNF‐α inhibitors with respect to responders patients (Pc < 0.05). This ?308GA genotype has been classified as high producer of this cytokine. This fact could actually be interesting to explain the different response of patients with IBD with respect to TNF‐α inhibitors. TNF‐α promoter gene polymorphism does not seem to play a role in IBD susceptibility, but particular TNF‐α genotypes may be involved in the different responses to TNF‐α inhibitor treatment in Spanish patients with IBD.  相似文献   
93.
Selective oxidation reactions represent a challenging task for conventional organic chemistry. Whole-cell biocatalysis provides a very convenient, easy to apply method to carry out different selective oxidation reactions including chemo-, regio-, and enantio–selective reactions. Streptomyces species are important biocatalysts as they can catalyze these selective reactions very efficiently owing to the wide diversity of enzymes and enzymatic cascades in their cell niche. In this review, we present and analyze most of the examples reported to date of oxidative reactions catalyzed by Streptomyces species as whole-cell biocatalysts. We discuss 33 different Streptomyces species and strains and the role they play in different oxidative reactions over the past five decades. The oxidative reactions have been classified into seven categories that include: hydroxylation of steroids/non-steroids, asymmetric sulfoxidations, oxidation of aldehydes, multi-step oxidations, oxidative cleavage, and N-oxidations. The role played by Streptomyces species as recombinant hosts catalyzing bio-oxidations has also been highlighted.

Types of oxidation reactions catalyzed by whole cells of different Streptomyces species.  相似文献   
94.
Background and study aimsAscites may be of undetermined origin despite comprehensive study. This study aimed to assess the accuracy and safety of conventional and interventional high-frequency peritoneal ultrasound in the diagnosis of patients with ascites of unclear origin.Patients and methodsA total of 62 patients were prospectively enrolled; they underwent conventional (3.5–5 MHz) and high-frequency (6–8 MHz) transabdominal peritoneal ultrasound to suggest the nature of ascites supplemented by fine needle aspiration cytology (FNAC) of ascites and/or core biopsy of the omentum or other extra-visceral masses for final histopathologic diagnosis. Laparoscopy or laparotomy was needed if biopsy was inconclusive.ResultsUltrasound-guided procedures were diagnostic in 55 (87.7%) patients. Thirty-six (58.1%) were benign, of whom 86% had tuberculous peritonitis, 26 (41.9%) were malignant, of whom 76.9% had peritoneal metastasis. High-frequency ultrasound was able to propose ultrasonographic criteria in a trial to diagnose the nature of ascites. Our proposed ultrasonographic criteria were based on the amount and texture of ascites in addition to the omental and mesenteric features. These were able to suggest the diagnosis with 80.7% sensitivity for malignant ascites and 75% specificity for benign ascites. Moreover, histopathological examination of tissues obtained by ultrasound-guided procedures increased the sensitivity to 88.5% and the specificity to 88.9% in diagnosing malignant and benign disease, respectively, with an overall diagnostic accuracy of 88.6%. These procedures were considered to be safe as only one major (haemoperitoneum) and two minor complications (temporary ascitic fistula) were reported.ConclusionHigh-frequency peritoneal ultrasound together with the minimally invasive ultrasound-guided FNAC/biopsy of extra-visceral lesions may be considered an effective and safe tool in the diagnosis of ascites of undetermined origin.  相似文献   
95.
PurposeAs a further step to elucidate the actual diverse spectrum of oncofertility practices for breast cancer around the globe, we present and discuss the comparisons of oncofertility practices for breast cancer in limited versus optimum resource settings based on data collected in the Repro-Can-OPEN Study Part I & II.MethodsWe surveyed 39 oncofertility centers including 14 in limited resource settings from Africa, Asia & Latin America (Repro-Can-OPEN Study Part I), and 25 in optimum resource settings from the United States, Europe, Australia and Japan (Repro-Can-OPEN Study Part II). Survey questions covered the availability of fertility preservation and restoration options offered to young female patients with breast cancer as well as the degree of utilization.ResultsIn the Repro-Can-OPEN Study Part I & II, responses for breast cancer and calculated oncofertility scores showed the following characteristics: (1) higher oncofertility scores in optimum resource settings than in limited resource settings especially for established options, (2) frequent utilization of egg freezing, embryo freezing, ovarian tissue freezing, GnRH analogs, and fractionation of chemo- and radiotherapy, (3) promising utilization of oocyte in vitro maturation (IVM), (4) rare utilization of neoadjuvant cytoprotective pharmacotherapy, artificial ovary, and stem cells reproductive technology as they are still in preclinical or early clinical research settings, (5) recognition that technical and ethical concerns should be considered when offering advanced and innovative oncofertility options.ConclusionsWe presented a plausible oncofertility best practice model to guide oncofertility teams in optimizing care for breast cancer patients in various resource settings.  相似文献   
96.
Saffron (Crocus sativus L.) is a medicinal plant, originally cultivated in the East and Middle East, and later in some Mediterranean countries. Saffron is obtained from the stigmas of the plant. Currently, the use of saffron is undergoing a revival. The medicinal virtues of saffron, its culinary use and its high added value have led to the clarification of its phytochemical profile and its biological and therapeutic characteristics. Saffron is rich in carotenoids and terpenes. The major products of saffron are crocins and crocetin (carotenoids) deriving from zeaxanthin, pirocrocin and safranal, which give it its taste and aroma, respectively. Saffron and its major compounds have powerful antioxidant and anti-inflammatory properties in vitro and in vivo. Anti-tumor properties have also been described. The goal of this review is to present the beneficial effects of saffron and its main constituent molecules on neuropsychiatric diseases (depression, anxiety and schizophrenia) as well as on the most frequent age-related diseases (cardiovascular, ocular and neurodegenerative diseases, as well as sarcopenia). Overall, the phytochemical profile of saffron confers many beneficial virtues on human health and, in particular, on the prevention of age-related diseases, which is a major asset reinforcing the interest for this medicinal plant.  相似文献   
97.
Microtubules have become an appealing target for anticancer drug development including mainly colchicine binding site inhibitors (CBSIs). A new series of novel trimethoxypyridine derivatives were designed and synthesized as tubulin targeting agents. In vitro anti-proliferative activities of the tested compounds compared to colchicine against hepatocellular carcinoma (HepG-2), colorectal carcinoma (HCT-116), and breast cancer (MCF-7) was carried out. Most of compounds showed significant cytotoxic activities. Compounds Vb, Vc, Vf, Vj and VI showed superior anti-proliferative activities to colchicine. Where compound VI showed IC50 values of 4.83, 3.25 and 6.11 μM compared to colchicine (7.40, 9.32, 10.41 μM) against HCT 116, HepG-2 and MCF-7, respectively. The enzymatic activity against tubulin enzyme was carried out for the compounds that showed high anti-proliferative activity. Also, compound VI exhibited the highest tubulin polymerization inhibitory effect with an IC50 value of 8.92 nM compared to colchicine (IC50 value = 9.85 nM). Compounds Vb, Vc, Vf, Vj, & VIIIb showed promising activities with IC50 values of 22.41, 17.64, 20.39, 10.75, 31.86 nM, respectively. Cell cycle and apoptosis test for compound VI against HepG-2 cells, indicated that compound VI can arrest cell cycle at G2/M phase, and can cause apoptosis at pre-G1 phase, with high apoptotic effect 18.53%. Molecular docking studies of the designed compounds confirmed the essential hydrogen bonding with CYS241 beside the hydrophobic interaction at the binding site compared to reference compounds which assisted in the prediction of the structure requirements for the detected antitumor activity.

Interaction of compounds VI (IC50 = 8.92 nM) (A) and Vj (IC50 = 10.75 nM) (B) with key amino acids of CBS.  相似文献   
98.
Abstract

Purpose: Evaluating the long-term impact of faculty development programs (FDPs) can help monitor the effectiveness of the program and identify areas for development. This study examined long-term differences in confidence, knowledge, behaviors, and policies of faculty members who attended FDPs on multiple choice question (MCQ) item analysis and faculty members who did not attend the FDPs.

Methods: A cross-sectional study design was used, by administering a 24-item survey to a representative sample (simple random selection) of 61 faculty members at King Abdulaziz University Faculty of Medicine.

Results: Among respondents, 34% did not attend FDPs; 53% attended 1–3 FDPs; and 13% attended more than 3 FDPs on MCQ item analysis. Results showed that faculty knowledge on elements of MCQ item analysis was significantly greater (p?=?.01) for members who attended the FDPs. Faculty who attended FDPs on MCQ item analysis were twice more likely to conduct item analysis in general (p?=?.020) and four times more likely to conduct item analysis for more than 70% of module examinations (p?=?.005).

Conclusion: FDPs focused on MCQ item analysis can yield systematic changes on faculty confidence, knowledge, and behaviors. Moreover, FDPs also need support from the department and need sustained strategic support to ensure continued effectiveness.  相似文献   
99.
100.
Preterm neonates represent one of the most transfused categories of patients. Their target hematocrits, however, are mainly based on expert opinion. The risk of transfusions are very high in the smallest preterm baby with a weak immune response, immature antioxidant ability, fragile germinal matrix and impaired cerebral autoregulation, yet red cell transfusions remain the only life saving measure in the baby with symptomatic anemia.Minimizing phlebotomy losses, following a restrictive transfusion policy and using screened, leukocyte depleted, irradiated, single donor blood remain the best means of avoiding the possible risks while maximizing the benefits of red cell transfusions in the preterm newborn.  相似文献   
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