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2.
Renal cell carcinoma (RCC) is the most common renal malignancy in adults and exhibits highly intrinsic and acquired resistance to standard therapeutic strategies. We sought to determine the anti-cancer activity of hydroalcoholic extract of Nigella sativa seeds (NSE) and thymoquinone (TQ). Human renal cell carcinoma (ACHN) and fibroblast L929 cell lines were treated with NSE and TQ, and cytotoxicity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Cell death pattern was determined by annexin V and propidium iodine (PI)-staining methods. Exposure to NSE, TQ and cisplatin significantly inhibited the growth of ACHN cells and showed significant increase of early apoptotic cells. Normal cells were more resistant to NSE and TQ-induced effects. The present study demonstrates that N. sativa and TQ exert anti-proliferative and pro-apoptotic effects on ACHN cells in a concentration and time-dependent manner, which suggests their potential to be used as a new therapeutic strategy for renal cancers.  相似文献   
3.
Understanding mechanisms causing pulmonary vascular disease (PVD) frequently requires a thorough understanding of the underlying structural changes in the pulmonary circulation. Animal models have been used extensively to study different forms of PVD but conventional experimental techniques are limited in their ability to allow the study of the whole pulmonary vasculature at once. In this study, we introduce novel techniques of arterial casting, high-resolution imaging and tree analysis to study the pulmonary circulation in rodent models. Male Sprague-Dawley rats were used at 20, 36, 52, 100 and 160 days of age. A technique involving arterial casting with Microfil silicone polymer, high-resolution micro-computed tomography (micro-CT) at 12.5 μm resolution and image data analysis involving segmentation and skeletonization was developed to both qualitatively and quantitatively describe the changes in the pulmonary vasculature with increasing age. Parameters identified to affect the quality of pulmonary arterial casting included polymer flow rate, total injected volume, polymer viscosity and polymerization time. By optimizing these parameters, we successfully created arterial casts of the pulmonary circulation in rats of different ages and demonstrated the feasibility of quantitatively characterizing the changes in the number of vessels with postnatal growth. These preliminary data suggest that the number of vessels with lumen diameters of 50-200 μm increases rapidly in both lungs between 52 and 100 days of age. With this new technique, the pulmonary vasculature can now be studied in a whole lung animal model to better understand the global effects of disease on vascular structure.  相似文献   
4.

Background  

Despite the rich literature on GERD, its cause and reason for increased prevalence remain obscure. Currently accepted mechanisms leave many questions unanswered. Nitrite chemistry at the GEJ is well described for carcinogenesis. Recent epidemiological and animal data have linked nitrates to GERD. “Nitrate reductase” of oral bacteria converts nitrates to nitrites. We hypothesized that nitrate reductase activity is higher in patients with erosive GERD, delivering more nitrite at the gastroesophageal-junction for a given nitrate intake.  相似文献   
5.

Background

Although great efforts are being undertaken to reduce child morbidity and mortality globally, there is limited knowledge about the need for pediatric surgical care. Some data on surgical need is available from hospital registries, but it is difficult to interpret for countries with limited surgical capacity.

Methods

A cross-sectional two-stage cluster-based sample survey was undertaken in Sierra Leone, using the Surgeons OverSeas Assessment of Surgical Need tool. Data were collected and analyzed on numbers of children needing surgical care and pediatric deaths that may have been averted if surgical care had been available.

Results

A total of 1,583 children out of 3,645 individuals (43.3 %) were interviewed. Most (64.0 %, n = 1,013) participants lived in rural areas. At the time of interview, 279 (17.6; 95 % confidence interval (95 % CI): 15.7–19.5 %) had a possible surgical condition in need of a consultation. Children in the northern and eastern provinces of Sierra Leone were much more likely to report a surgical problem than those in the urban-west.

Conclusions

There is a high need for surgical care in the pediatric population of Sierra Leone. While additional resources should be allocated to address that need, more research is needed. Ideally, questions on surgically treatable conditions should be added to the frequently performed health care surveys on the pediatric population.  相似文献   
6.
The proliferation, cell cycle exit and differentiation of progenitor cells are controlled by several different factors. The chromodomain protein mortality factor 4-like 1 (Morf4l1) has been ascribed a role in both proliferation and differentiation. Little attention has been given to the existence of alternative splice variants of the Morf4l1 mRNA, which encode two Morf41l isoforms: a short isoform (S-Morf4l1) with an intact chromodomain and a long isoform (L-Morf4l1) with an insertion in or in the vicinity of the chromodomain. The aim of this study was to investigate if this alternative splicing has a function during development. We analysed the temporal and spatial distribution of the two mRNAs and over-expressed both isoforms in the developing retina. The results showed that the S-Morf4l1 mRNA is developmentally regulated. Over-expression of S-Morf4l1 using a retrovirus vector produced a clear phenotype with an increase of early-born neurons: retinal ganglion cells, horizontal cells and cone photoreceptor cells. Over-expression of L-Morf4l1 did not produce any distinguishable phenotype. The over-expression of S-Morf4l1 but not L-Morf4l1 also increased apoptosis in the infected regions. Our results suggest that the two Morf4l1 isoforms have different functions during retinogenesis and that Morf4l1 functions are fine-tuned by developmentally regulated alternative splicing. The data also suggest that Morf4l1 contributes to the regulation of cell genesis in the retina.  相似文献   
7.
8.
The use of sentinel node surgery for esophageal carcinoma is still under investigation. We evaluated the data available in the literature on this topic, and herein present the results in a systematic review format. PUBMED, SCOPUS, the ISI web of knowledge and the information from the annual meetings of the Japan Esophageal Society were searched using the search terms: “(esophagus OR esophageal) AND sentinel”. The outcomes of interest were the detection rate and sensitivity. Overall, 18 studies were included. The pooled detection rate was 89.2 % [82.6–93.5]. Patients with T1 and two tumors had a 17 % higher detection rate compared to those with T3 and four tumors. The pooled sensitivity was 84 % [78–88 %]. The sensitivity was higher for adenocarcinoma compared to squamous cell carcinoma (SCC) (91 vs. 81 %). In the SCC patients, there was a trend toward decreased sensitivity associated with an increasing tumor depth (T1:88 %, T2:76 %, T3:50 %). Our analysis indicated that sentinel node biopsy is useful in adenocarcinoma patients. For SCC patients, including only cN0 patients (preferably T1 and 2) would increase the detection rate and sensitivity. Due to the limited number of high-quality studies, drawing any more definite conclusions is impossible. Large cohort studies with a standardized and consistent design will be needed in the future.  相似文献   
9.
We aimed to compare the association of high-sensitivity C-reactive protein (CRP) and National Institutes of Health Stroke Scale (NIHSS) score with mortality risk and to determine the optimal threshold of CRP for prediction of mortality in ischemic-stroke patients. A series of 162 patients with first-ever ischemic-stroke admitted within 24 h after onset of symptoms was enrolled. CRP and NIHSS score were estimated on admission and their predictive abilities for mortality at 7 days were determined by logistic-regression analyses. Receiver-Operating Characteristic (ROC) curves were depicted to identify the optimal cut-off of CRP, using the maximum Youden-index and the shortest-distance methods. Deceased patients had higher levels of CRP and NIHSS on admission (8.87 ± 7.11 vs. 2.20 ± 4.71 mg/l for CRP, and 17.31 ± 6.36 vs. 8.70 ± 4.85 U for NIHSS, respectively, P < 0.01). CRP and NIHSS were correlated with each other (r 2 = 0.39, P < 0.001) and were also independently associated with increased risk of mortality [odds ratios (95 % confidence interval) of 1.16 (1.05–1.28) and 1.20 (1.07–1.35) for CRP and NIHSS, respectively, P < 0.01]. The areas under the ROC curves of CRP and NIHSS for mortality were 0.82 and 0.84, respectively. The CRP value of 2.2 mg/l was identified as the optimal cut-off value for prediction of mortality within 7 days (sensitivity: 0.81, specificity: 0.80). Thus, CRP as an independent predictor of mortality following ischemic-stroke is comparable with NIHSS and the value of 2.2 mg/l yields the optimum sensitivity and specificity for mortality prediction.  相似文献   
10.
Herein we combine cell sheet technology and electrospun scaffolding to rapidly generate circumferentially aligned tubular constructs of human aortic smooth muscles cells with contractile gene expression for use as tissue engineered blood vessel media. Smooth muscle cells cultured on micropatterned and N-isopropylacrylamide-grafted (pNIPAm) polydimethylsiloxane (PDMS), a small portion of which was covered by aligned electrospun scaffolding, resulted in a single sheet of unidirectionally aligned cells. Upon cooling to room temperature, the scaffold, its adherent cells, and the remaining cell sheet detached and were collected on a mandrel to generating tubular constructs with circumferentially aligned smooth muscle cells which possess contractile gene expression and a single layer of electrospun scaffold as an analogue to a small diameter blood vessel's internal elastic lamina (IEL). This method improves cell sheet handling, results in rapid circumferential alignment of smooth muscle cells which immediately express contractile genes, and introduction of an analogue to small diameter blood vessel IEL.  相似文献   
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