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61.
Molecular approaches offer a means of testing archived samples stored as dried blood spots in settings where standard blood cultures are not possible. Peripheral blood films are one suggested source of material, although the sensitivity of this approach has not been well defined. Thin blood smears and dried blood spots from a severe pediatric malaria study were assessed using specific polymerase chain reaction (PCR) primers to detect non-typhoidal Salmonella (NTS; MisL gene), Streptococcus pneumoniae (lytA), and Plasmodium falciparum (18S rRNA). Of 16 cases of NTS and S. pneumoniae confirmed on blood culture, none were positive by PCR using DNA extracts from blood films or dried blood spots. In contrast, four of 36 dried blood spots and two of 178 plasma samples were PCR positive for S. pneumoniae, despite negative bacterial blood cultures, suggesting false positives. Quantitative assessment revealed that the effective concentration of P. falciparum DNA in blood films was three log orders of magnitude lower than for dried blood spots. The P. falciparum kelch13 gene could not be amplified from blood films. These findings question the value of blood PCR-based approaches for detection of NTS and S. pneumoniae, and show that stored blood films are an inefficient method of studying P. falciparum.  相似文献   
62.

Ethnopharmacological relevance

The bark of Tecomella undulata is traditionally claimed in the treatment of various disease ailments including obesity and cancer. Till now there are no studies about anti-obesity activity of Tecomella undulata bark.

Aim of the study

The present study was aimed to establish a scientific evidence for anti-obesity efficiency of ethyl acetate extract of Tecomella undulata bark (EATUB). Further to standardize the active fractions of EATUB using different biomarkers.

Materials and methods

We investigated activity of EATUB fractions (F1–F7) using 3T3-L1 fibroblasts. Further, F1-mediated effects were characterized by determining mRNA and protein levels of SIRT1, one of the key targets for the treatment of obesity, using semi-quantitative RT-PCR (sqRT-PCR) and western blot analysis. The consequences of modulation of SIRT1 on mRNA and protein levels of various adipogenesis mediators like PPARγ, C/EBPα, E2F1, leptin, adiponectin and LPL were also studied. In vivo studies were performed using High Fat Diet (HFD) obese mice.

Results

Our data showed that compared to controls, preadipocytes and adipocytes incubated with F1 exhibited a significant decrease in adipogenesis and lipogenesis. In addition, sqRT-PCR and western blot analysis showed significant increase in SIRT1 and adiponectin levels and decrease in PPARγ, C/EBPα, E2F1, leptin and LPL levels in preadipocytes and adipocytes. In vivo studies of F1 in HFD induced obese mice showed significant improvement in lipid profile and glucose levels. The bioactive fraction (F1) was determined to possess 4.95% of ferulic acid.

Conclusion

Thus, our findings signified the beneficial effects of Tecomella undulata bark in pharmacologic interventions related to obesity and metabolic disorders. Ferulic acid and rutin are being reported and quantified for the first time from the bark of Tecomella undulata.  相似文献   
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Journal of Neuro-Oncology - Primary central nervous system lymphoma (PCNSL) is a subtype of non-Hodgkin’s lymphoma that involves the brain, spinal cord, or leptomeninges, without evidence of...  相似文献   
66.
OBJECTIVE: To investigate how term and preterm labor (PTL) influence the balance between maternal proinflammatory and antiinflammatory responses as measured by expression of major histocompatibility complex (MHC) Class II on maternal monocytes and tumor necrosis factor-alpha (TNF-alpha) production by in vitro stimulation of whole blood by lipopolysaccharide (LPS). METHODS: Blood was taken from the following women (n=118): term elective cesarean delivery or in spontaneous labor, in premature labor, or with preterm premature rupture of the membranes (PROM) at less than 32 weeks, and gestation-matched reference group. Monocyte MHC Class II expression was measured by flow cytometry using a dual-staining technique. Plasma cytokine levels were assayed using a cytometric bead array system. In vitro whole blood stimulation with LPS was also performed, and cytokine production was measured. RESULTS: Term labor was associated with a fall in the percentage of monocytes expressing MHC Class II, compared with third trimester of pregnancy, P<.05 and a reduction in LPS-stimulated TNF-alpha production. This fall in MHC Class II was even more pronounced in PTL and preterm PROM groups compared with the reference group, P<.01. CONCLUSION: There was evidence of reduced expression of monocyte MHC Class II and LPS-stimulated TNF-alpha in term and preterm labor. This pattern of reduced MHC Class II expression and reduced TNF-alpha production is known as monocyte hyporesponsiveness or immune paresis. Detection of this state may provide insights into the maternal inflammatory status and be of use in the management of women with threatened PTL or preterm PROM. LEVEL OF EVIDENCE: II.  相似文献   
67.
In the transforming growth factor β (TGF-β) signaling pathway, TGF-β1 and TGF-β receptor 2 (TGF-βR2) are essential regulatory components which play an important role in different type of cancer. Expressions of TGF-β1 and TGF-βR2 were done by real-time qPCR in both biopsy and blood samples collected from esophageal squamous cell carcinoma (ESCC) patients (n = 76). The expression profiles were correlated with different lifestyle factors and clinicopathological parameters. Kaplan-Meier survival analysis and Cox regression analysis were performed to estimate survival and hazard outcomes of different parameters. TGF-β1 showed upregulation in 91% tissue samples (2.84 ± 1.34*) and 55% blood samples (2.43 ± 1.24*) whereas expression of TGF-βR2 showed downregulation in 89% tissue samples (0.27 ± 0.23*) and 75% blood samples (0.30 ± 0.26*). Among all the parameters, TGF-β1 expression is significant with histopathology grade, consumption of betel nut and smoked food whereas TGF-βR2 expression is significant only with dysphagia grade in both blood and tissue samples and while analyzing both male and female patients separately. Consuming alcohol and hot food, difference in tumor stage and metastasis were found to have statistically significant (P < 0.05) impact on survival and mortality of male patients while consuming hot food, tobacco, metastasis and TGF-βR2 expression in tissue level were found to associate with survival and mortality of female patients. Expression of both TGF-β1 and TGF-βR2 in tissue samples may be prospective biomarkers for screening of ESCC among the Northeast population. Survival outcomes and hazard analysis supports the importance of some clinicopathological and lifestyle factors on ESCC development, whereas expression study depicts association of change in expression of the studied genes in ESCC patients.*Mean fold change.  相似文献   
68.
Testing for the CALR mutation is included in the updated WHO criteria for essential thrombocythaemia (ET) and primary myelofibrosis (PMF). We report on the application of the CAL2 monoclonal antibody, raised against the mutated CALR gene to myeloid cases. The immunostain was used on 116 acute myeloid leukaemias (AML) and 66 myeloproliferative neoplasms (MPN) or myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN). None of AML cases was stained by the CAL2 antibody, while 20/66 MPNs and MDS/MPNs appeared positive. Fourteen of the latter cases were studied by molecular techniques, and all showed aberrations of the CALR gene. In addition, CAL2 positivity was found in some small‐sized elements besides megakaryocytes. By double staining, these elements corresponded to small megakaryocytes as well as both erythroid and myeloid precursors. This finding suggests possible occurrence of CALR gene abnormalities in a stem cell.  相似文献   
69.
The visual outcome of 164 intracapsular cataract extractions (ICCE) performed in 158 patients at an eye-camp was evaluated. 93.3% had a preoperative visual acuity of less than 3/60. On the 4th/5th post-operative day, 39.3% had a visual acuity between 6/18 and 6/36; 84.7% had vision better than 3/60. Six weeks post-operatively, 44.1% had visual acuity better than 6/18 and a total of 84.1% better than 3/60. The vision of 40.7% improved between the 4th/5th post-operative day and the follow-up visit at 6 weeks. 46.4% of patients had post-operative corrected visual acuity better than 6/18, 24.3% had vision between 6/18 and 6/36, and a total of 84.3% had vision better than 3/60. The patients' satisfaction in terms of improvement in mobility and ability to do housework at 6 weeks after the operation correlated better with the improvement in vision in terms of the number of Snellen's lines than with the actual post-operative visual acuity.  相似文献   
70.
Recent developments in the generation and characterization of genetically engineered mouse models of human cancer have resulted in notable improvements in these models as platforms for preclinical target validation and experimental therapeutics. In this review, we enumerate the criteria used to assess the accuracy of various models with respect to human disease and provide some examples of their prognostic and therapeutic utility, focusing on models for cancers that affect the largest populations. Technological advancements that allow greater exploitation of genetically engineered mouse models, such as RNA interference in vivo, are described in the context of target and drug validation. Finally, this review discusses stratagems for, and obstacles to, the application of these models in the drug development process.  相似文献   
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