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21.
Recent evidence suggests an intriguing link between p53 and the Fas pathway. To evaluate this association further, we utilized a recombinant adenoviral vector (AdWTp53) to overexpress wild-type p53 in lung cancer (A549, H23, EKVX and HOP92) and breast cancer (MDA-MB-231 and MCF-7) cell lines and observed an increase in the Fas/CD95/APO-1 protein levels. Furthermore, this increase correlated with the sensitivity of the cell lines to p53-mediated cytotoxicity. To examine the effects of Fas over-expression in cells resistant to p53 over-expression, we constructed AdFas, an adenoviral vector capable of transferring functional human Fas to cancer cells. Interestingly, infection of p53-resistant MCF-7 cells with AdFas sensitized them to p53-mediated apoptosis. These studies indicate that combined over-expression of Fas and wild-type p53 may be an effective cancer gene therapy approach, especially in cells relatively resistant to p53 over-expression.  相似文献   
22.
Nuclear DNA amount of five species ofCelosia ranging from 2x to 12x varies from 3.26 (2x) to 9.70pg (12x). The diploidC. trigyna has twice as much DNA/basic genome as other taxa, which is commensurate with its taxonomic position and genetic isolation. There is insignificant variation in DNA/basic genome among 4x, 8x, and 12x taxa. Therefore, DNA/nucleus shows a strong positive correlation with ploidy level. The different accessions of 4x taxa show constancy of DNA amounts. There is no correlation of seed weight with DNA amount.  相似文献   
23.

Background

Lung clearance index (LCI) is a measure of abnormal ventilation distribution derived from the multiple breath inert gas washout (MBW) technique. We aimed to determine the clinical utility of LCI in non-CF bronchiectasis, and to assess two novel MBW parameters that distinguish between increases in LCI due to specific ventilation inequality (LCIvent) and increased respiratory dead space (LCIds).

Methods

Forty-three patients with non-CF bronchiectasis and 18 healthy control subjects underwent MBW using the sulphur hexafluoride wash-in technique, and data from 40 adults with CF were re-analysed. LCIvent and LCIds were calculated using a theoretical two-compartment lung model, and represent the proportional increase in LCI above its ideal value due to specific ventilation inequality and increased respiratory dead space, respectively.

Results

LCI was significantly raised in patients with non-CF bronchiectasis compared to healthy controls (9.99 versus 7.28, p < 0.01), and discriminated well between these two groups (area under receiver operating curve = 0.90, versus 0.83 for forced expiratory volume in one second [% predicted]). LCI, LCIvent and LCIds were repeatable (intraclass correlation coefficient > 0.75), and correlated significantly with measures of spirometric airflow obstruction.

Conclusion

LCI is repeatable, discriminatory, and is associated with spirometric airflow obstruction in patients with non-CF bronchiectasis. LCIvent and LCIds are a practical and repeatable alternative to phase III slope analysis and may allow a further level of mechanistic information to be extracted from the MBW test in patients with severe ventilation heterogeneity.  相似文献   
24.
Summary The microbial transformation of bile acids that takes place in the lower alimentary tract plays an important role in the in vivo metabolism of bile acids and also of cholesterol in general. Most of the transforming reactions involved can be reproduced in in vitro cultures of mixed intestinal microflora: hydrolysis of the peptide bond in the conjugated bile acids, removal of the 7α-OH group, and dehydrogenation of the α-OH substituents at C-7, C-3 and C-12. The last reaction, which leads to the formation an oxo group, is reversible and a stereospecific reduction of, the oxo moiety into a b-OH group has been shown to be carried out.  相似文献   
25.

Background

We have previously investigated the microlocalisation of M1 and M2 macrophages in NSCLC. This study investigated the non-macrophage (NM) expression of proteins associated with M1 and M2 macrophages in NSCLC.

Methods

Using immunohistochemistry, CD68+ macrophages and proteins associated with either a cytotoxic M1 phenotype (HLA-DR, iNOS, and MRP 8/14), or a non-cytotoxic M2 phenotype (CD163 and VEGF) were identified. NM expression of the markers was analysed in the islets and stroma of surgically resected tumours from 20 patients with extended survival (ES) (median 92.7 months) and 20 patients with poor survival (PS) (median 7.7 months).

Results

The NM expression of NM-HLA-DR (p<0.001), NM-iNOS (p = 0.02) and NM-MRP 8/14 (p = 0.02) was increased in ES compared to PS patients in the tumour islets. The tumour islet expression of NM-VEGF, was decreased in ES compared to PS patients (p<0.001). There was more NM-CD163 expression (p = 0.04) but less NM-iNOS (p = 0.002) and MRP 8/14 (p = 0.01) expression in the stroma of ES patients compared with PS patients. The 5-year survival for patients with above and below median NM expression of the markers in the islets was 74.9% versus 4.7% (NM-HLA-DR p<0.001), 65.0% versus 14.6% (NM-iNOS p = 0.003), and 54.3% versus 22.2% (NM-MRP 8/14 p = 0.04), as opposed to 34.1% versus 44.4% (NM-CD163 p = 0.41) and 19.4% versus 59.0% (NM-VEGF p = 0.001).

Conclusions

Cell proteins associated with M1 and M2 macrophages are also expressed by other cell types in the tumour islets and stroma of patients with NSCLC. Their tissue and cellular microlocalisation is associated with important differences in clinical outcome.  相似文献   
26.

Background

Limited knowledge exists on early HIV events that may inform preventive and therapeutic strategies. This study aims to characterize the earliest immunologic and virologic HIV events following infection and investigates the usage of a novel therapeutic strategy.

Methods and Findings

We prospectively screened 24,430 subjects in Bangkok and identified 40 AHI individuals. Thirty Thais were enrolled (8 Fiebig I, 5 Fiebig II, 15 Fiebig III, 2 Fiebig IV) of whom 15 completed 24 weeks of megaHAART (tenofovir/emtricitabine/efavirenz/raltegravir/maraviroc). Sigmoid biopsies were completed in 24/30 at baseline and 13/15 at week 24.At baseline, the median age was 29 years and 83% were MSM. Most were symptomatic (87%), and were infected with R5-tropic (77%) CRF01_AE (70%). Median CD4 was 406 cells/mm3. HIV RNA was 5.5 log10 copies/ml. Median total blood HIV DNA was higher in Fiebig III (550 copy/106 PBMC) vs. Fiebig I (8 copy/106 PBMC) (p = 0.01) while the median %CD4+CCR5+ gut T cells was lower in Fiebig III (19%) vs. Fiebig I (59%) (p = 0.0008).After 24 weeks of megaHAART, HIV RNA levels of <50 copies were achieved in 14/15 in blood and 13/13 in gut. Total blood HIV DNA at week 0 predicted reservoir size at week 24 (p<0.001). Total HIV DNA declined significantly and was undetectable in 3 of 15 in blood and 3 of 7 in gut. Frequency of CD4+CCR5+ gut T cells increased from 41% at baseline to 64% at week 24 (p>0.050); subjects with less than 40% at baseline had a significant increase in CD4+CCR5+ T cells from baseline to week 24 (14% vs. 71%, p = 0.02).

Conclusions

Gut T cell depletion and HIV reservoir seeding increases with progression of AHI. MegaHAART was associated with immune restoration and reduced reservoir size. Our findings could inform research on strategies to achieve HIV drug-free remission.  相似文献   
27.
Smith-Lemli-Opitz syndrome is an autosomal recessively inherited disorder. A severe defect in cholesterol biosynthesis has been identified leading to abnormally low plasma cholesterol levels and elevated levels of the cholesterol precursor 7-dehydrocholesterol, the result of deficiency of 7-dehydrocholesterol reductase. We describe one such child with Smith-Lemli-Opitz syndrome. This child had clinical features similar to Smith-Lemli-Opitz syndrome like facial dysmorphism and cardiac and renal anomalies with failure to thrive.  相似文献   
28.
Surface modification of glutaraldehyde fixed bovine pericardium (GFBP) was successfully carried out with hyaluronic acid (HA) derivatives. At first, HA was chemically modified with adipic dihydrazide (ADH) to introduce hydrazide functional group into the carboxyl group of HA backbone. Then, GFBP was surface modified by grafting HA-ADH to the free aldehyde groups on the tissue and the subsequent HA-ADH hydrogel coating. HA-ADH hydrogels could be prepared through selective crosslinking at low pH between hydrazide groups of HA-ADH and crosslinkers containing succinimmidyl moieties with minimized protein denaturation. When HA-ADH hydrogels were prepared at low pH of 4.8 in the presence of erythropoietin (EPO) as a model protein, EPO release was continued up to 85% of total amount of loaded EPO for 4 days. To the contrary, only 30% of EPO was released from HA-ADH hydrogels prepared at pH=7.4, which might be due to the denaturation of EPO during the crosslinking reaction. Because the carboxyl groups on the glucuronic acid residues are recognition sites for HA degradation by hyaluronidase, the HA-ADH hydrogels degraded more slowly than HA hydrogels prepared by the crosslinking reaction of divinyl sulfone with hydroxyl groups of HA. Following a two-week subcutaneous implantation in osteopontin-null mice, clinically significant levels of calcification were observed for the positive controls without any surface modification. However, the calcification of surface modified GFBP with HA-ADH and HA-ADH hydrogels was drastically reduced by more than 85% of the positive controls. The anti-calcification effect of HA surface modification was also confirmed by microscopic analysis of explan ted tissue after staining with Alizarin Red S for calcium, which followed the trend as observed with calcium quantification.  相似文献   
29.
Current interest in the potential use of pancreatic stem-cells in the treatment of insulin dependent diabetes mellitus has led to increased research into normal pancreatic development. Pancreatic organogenesis involves branching morphogenesis of undifferentiated epithelium within surrounding mesenchyme. Current understanding is that the pancreatic islets develop exclusively from the epithelium of the embryonic buds. However, a cellular contribution to islets by mesenchyme has not been conclusively excluded. We present evidence that the mesenchyme of both the dorsal pancreatic bud and stomach rudiment make a substantial contribution of cells to islets during development in a three-dimensional avian model. These data suggest that mesenchyme can be a source not only of signals but also of cells for the definitive epithelia, making pancreatic organogenesis more akin to that of the kidney than to other endodermal organs. This raises the possibility for the use of mesenchymal cells as stem-or progenitor-cells for islet transplantation.Key Words: islets, stem-cells, development, epithelium, mesenchyme, pancreas, stomach, chick-quail, 3-dimensional, endocrine  相似文献   
30.

Objective

To compare central nervous system (CNS) outcomes in participants treated during acute HIV infection with standard combination antiretroviral therapy (cART) vs. cART plus integrase inhibitor and CCR5 antagonist (cART+).

Design

24-week randomized open-label prospective evaluation.

Method

Participants were evaluated then randomized to initiate cART (efavirenz, tenofovir, and either emtricitabine or lamivudine) vs. cART+ (cART plus raltegravir and maraviroc) during acute HIV and re-evaluated at 4, 12 and 24 weeks. We examined plasma and CSF cytokines, HIV RNA levels, neurological and neuropsychological findings, and brain MRS across groups and compared to healthy controls.

Results

At baseline, 62 participants were in Fiebig stages I-V. Randomized groups were similar for mean age (27 vs. 25, p = 0.137), gender (each 94% male), plasma log10 HIV RNA (5.4 vs. 5.6, p = 0.382), CSF log10 HIV RNA (2.35 vs. 3.31, p = 0.561), and estimated duration of HIV (18 vs. 17 days, p = 0.546). Randomized arms did not differ at 24 weeks by any CNS outcome. Combining arms, all measures concurrent with antiretroviral treatment improved, for example, neuropsychological testing (mean NPZ-4 of -0.408 vs. 0.245, p<0.001) and inflammatory markers by MRS (e.g. mean frontal white matter (FWM) choline of 2.92 vs. 2.84, p = 0.045) at baseline and week 24, respectively. Plasma neopterin (p<0.001) and interferon gamma-induced protein 10 (IP-10) (p = 0.007) remained elevated in participants compared to controls but no statistically significant differences were seen in CSF cytokines compared to controls, despite individual variability among the HIV-infected group.

Conclusions

A 24-week course of cART+ improved CNS related outcomes, but was not associated with measurable differences compared to standard cART.  相似文献   
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