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51.
An antimetastatic role for decorin in breast cancer 总被引:1,自引:0,他引:1
Goldoni S Seidler DG Heath J Fassan M Baffa R Thakur ML Owens RT McQuillan DJ Iozzo RV 《The American journal of pathology》2008,173(3):844-855
Decorin, a member of the small leucine-rich proteoglycan gene family, down-regulates members of the ErbB receptor tyrosine kinase family and attenuates their signaling, leading to growth inhibition. We investigated the effects of decorin on the growth of ErbB2-overexpressing mammary carcinoma cells in comparison with AG879, an established ErbB2 kinase inhibitor. Cell proliferation and anchorage-independent growth assays showed that decorin was a potent inhibitor of breast cancer cell growth and a pro-apoptotic agent. When decorin and AG879 were used in combination, the inhibitory effect was synergistic in proliferation assays but only additive in both colony formation and apoptosis assays. Active recombinant human decorin protein core, AG879, or a combination of both was administered systemically to mice bearing orthotopic mammary carcinoma xenografts. Primary tumor growth and metabolism were reduced by approximately 50% by both decorin and AG879. However, no synergism was observed in vivo. Decorin specifically targeted the tumor cells and caused a significant reduction of ErbB2 levels in the tumor xenografts. Most importantly, systemic delivery of decorin prevented metastatic spreading to the lungs, as detected by novel species-specific DNA detection and quantitative assays. In contrast, AG879 failed to have any effect. Our data support a role for decorin as a powerful and effective therapeutic agent against breast cancer due to its inhibition of both primary tumor growth and metastatic spreading. 相似文献
52.
Spectrum of holoprosencephaly 总被引:1,自引:0,他引:1
Objective : To conduct a clinical study of holoprosencephaly (HPE).Method : Thirteen cases of HPE were studied regarding their clinical features, family history, and prenatal and imaging studies.
Chromosomal analysis was done whenever fresh sample was available.Results : Six cases were antenatally detected by ultrasound; four cases were stillborn. Three cases were identified by neuroimaging
done a part of evaluation of developmental delay or cleft lip. Eleven of them had facial anomalies characteristics of HPE.
Two of these had subtle facial features and microcephaly. Karyotype was abnormal in 2 of 7 cases studied.Conclusion : Most of the cases of HPE present antenatally or at birth. Milder forms like lobar and semilobar can present as developmental
delay during infancy. Facial anomalies are usually associated with HPE. Chromosomal study of the case and clinical examination
of the parents is essential for providing information regarding risk of recurrence to the family. 相似文献
53.
Campylobacter coli in swine production: antimicrobial resistance mechanisms and molecular epidemiology 下载免费PDF全文
The aim of this study was to determine antimicrobial resistance, to evaluate and compare the use of two genotyping methods for molecular epidemiology purposes, and to determine the genotypic diversity of Campylobacter coli of porcine origin. A total of 100 C. coli isolates from swine were tested for susceptibility to six antimicrobials using the agar dilution method and genotyped using two high-resolution fingerprinting approaches: multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Evaluation of the methods was based on their resistance patterns, discriminatory indexes (DI), high test throughputs, costs, and turnaround times. Resistance to erythromycin and tetracycline was the most common. Both genotypic methods were found to have high discriminatory power, although MLST had a higher DI (0.936) than PFGE (DI = 0.889). It also had a higher throughput than PFGE. Isolates were clustered into 27 groups by MLST compared to 11 by PFGE. MLST was able to further discriminate the isolates grouped under the same cluster by PFGE. Out of the 65 MLST sequence types (STs) identified among the total isolates, 50 were reported for the first time. Most STs were found to be specific to the farm (n = 38) and to slaughter (n = 22). Resistance against tetracycline and erythromycin was encoded by the tet(O) gene and a A2075G point mutation in the 23S rRNA gene, respectively. A high ciprofloxacin MIC (>64 microg/liter) was conferred by a point mutation in the gyrA gene. The weak clonal structure of the C. coli population among swine was further highlighted by the index of association value of 0.293. The findings of this study indicate that multidrug-resistant diverse C. coli strains exhibiting resistance to ciprofloxacin and erythromycin are concerning, since these are the drugs of choice for treating invasive campylobacteriosis cases in humans. 相似文献
54.
55.
A Bal S Verma K Joshi A Singla R Thakur S Arora G Singh 《Virchows Archiv : an international journal of pathology》2012,461(3):305-312
BRCA1 mutations have been associated with hereditary breast cancer only. Recent studies indicate that a subgroup of sporadic breast cancer might also be associated with reduction in BRCA1 mRNA levels and protein expression. However, the mechanism of reduced mRNA and protein expression is yet not fully elucidated. This study aims to assess BRCA1 protein expression and the role of BRCA1 promoter methylation in sporadic breast cancer in North Indian population and to correlate these with known prognostic factors and molecular profiles of breast cancer. BRCA1 protein expression was normal (>50?% tumour cells) in 41 (43?%) cases, reduced (20-50?% tumour cells) in 33 (35?%) cases and absent/markedly reduced (<20?% tumour cells) in 21 (22.1?%) cases. Cases which were negative for BRCA1 protein were more frequently positive for basal markers (29 versus 5?%) and were more often ER-negative (62 versus 39?%) than BRCA1-positive tumours. Methylation of BRCA1 promoter region was seen in 11/45 cases (24?%). All 11 cases showing BRCA1 methylation had absent (eight cases) or reduced (three cases) BRCA1 protein expression. BRCA1 protein-negative tumours were more frequently basal marker-positive and ER-negative, highlighting the 'BRCAness' of sporadic breast cancer with loss of BRCA1 protein expression through promoter hypermethylation similar to hereditary breast cancer with BRCA1 mutations. Loss of BRCA1 in sporadic breast cancer suggests that therapeutics targeting BRCA1 pathway in hereditary breast cancer like PARP inhibitors might be used as therapeutic targets for sporadic breast tumours. 相似文献
56.
Agarwal S Thakur K Kanga A Singh G Gupta P 《Indian journal of pathology & microbiology》2008,51(2):298-300
Candida lipolytica is weakly pathogenic yeast, which is rarely isolated from the blood. We recovered this species from repeated blood samples and in the central venous catheter in a debilitated pediatric patient of tubercular meningitis. Identity was established on the basis of colony morphology and sugar assimilation tests (ID 32C assimilation profile). The fungemia and associated fever subsided after the removal of catheter and amphotericin B therapy. The data suggest that though of low virulence and usually a contaminant, C. lipolytica is emerging yeast pathogen in cases of catheter-related candidemia. Pathogenicity is indicated by isolation from repeated samples as in our case. Intensive therapy is recommended in cases not resolving spontaneously or responding to removal of catheter alone. 相似文献
57.
D. J. Roberts K. Sanok H. Chen M. Chan P. Yurt A. K. Thakur G. L. DeVito H. Murli L. F. Stankowski Jr. 《Environmental and molecular mutagenesis》2012,53(4):297-303
A flow cytometric procedure for determining mitotic index (MI) as part of the metaphase chromosome aberrations assay, developed and utilized routinely at Pfizer as part of their standard assay design, has been adopted successfully by Covance laboratories. This method, using antibodies against phosphorylated histone tails (H3PS10) and nucleic acid stain, has been evaluated by the two independent test sites and compared to manual scoring. Primary human lymphocytes were treated with cyclophosphamide, mitomycin C, benzo(a)pyrene, and etoposide at concentrations inducing dose‐dependent cytotoxicity. Deming regression analysis indicates that the results generated via flow cytometry (FCM) were more consistent between sites than those generated via microscopy. Further analysis using the Bland–Altman modification of the Tukey mean difference method supports this finding, as the standard deviations (SDs) of differences in MI generated by FCM were less than half of those generated manually. Decreases in scoring variability owing to the objective nature of FCM, and the greater number of cells analyzed, make FCM a superior method for MI determination. In addition, the FCM method has proven to be transferable and easily integrated into standard genetic toxicology laboratory operations. Environ. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc. 相似文献
58.
Thakur G Naqvi MA Rousseau D Pal K Mitra A Basak A 《Journal of biomaterials science. Polymer edition》2012,23(5):645-661
Emulsion gels are now emerging as a new class of biomaterials for controlled-release applications. Novel food-grade emulsion gels consisting of indomethacin-loaded vegetable oil droplets dispersed within genipin-cross-linked gelatin-based hydrogels were characterized for their physical and drug-release properties. Varying the weight ratio of the aqueous and oil phases between 5:1 and 5:5 was used to modulate construct swelling and drug release. The dispersed oil droplets generally became larger, more polydispersed and aggregated with an increase in oil fraction. Cross-linking with genipin increased the puncture strength of the gels vs. their uncross-linked counterparts and was necessary to prevent breakdown. Swelling of the emulsion gels demonstrated Fickian behaviour at all gelatin: oil ratios. Indomethacin release followed Fickian diffusion at higher oil fractions only, demonstrating coupled Fickian and super-Case-II transport at lower oil ratios (5:1, 5:2 and 5:3). Overall, the introduction of a dispersed oil phase within a hydrogel was exploited for the release of hydrophobic bioactive compounds, with tailoring of composition used to significantly alter release kinetics. 相似文献
59.
Müller WE Engel S Wang X Wolf SE Tremel W Thakur NL Krasko A Divekar M Schröder HC 《Biomaterials》2008,29(7):771-779
Bioencapsulation is an intriguing way to immobilize biological materials, including cells, in silica, metal-oxides or hybrid sol-gel polymers. Until now only the sol-gel precursor technology was utilized to immobilize bacteria or yeast cells in silica. With the discovery of silicatein, an enzyme from demosponges that catalyzes the formation of poly(silicate), it became possible to synthesize poly(silicate) under physiological (ambient) conditions. Here we show that Escherichia coli can be transformed with the silicatein gene, its expression level in the presence of isopropyl beta-D-thiogalactopyranoside (IPTG) can be efficiently intensified by co-incubation with silicic acid. This effect could be demonstrated on the level of recombinant protein synthesis as well as by immunostaining analysis. The heterologously produced silicatein is enzymatically active, as confirmed by staining with Rhodamine 123 (formation for poly[silicate] from silicic acid) and by reacting free silicic acid with the beta-silicomolybdato color system. Electron microscopic analysis revealed that the bacteria that express silicatein form a viscous cover around them when growing in the presence of silicic acid. Finally, we demonstrate that the growth kinetics of E. coli remains unaffected whether or not the bacteria had been transformed with silicatein or grown in medium, supplemented with silicic acid. It is concluded that silicatein-mediated encapsulation of bacteria with silica might improve, extend and optimize the range of application of bacteria for the production of recombinant protein. 相似文献
60.
Gupta Manisha Krishan Pawan Kaur Amarjot Arora Sandeep Trehanpati Nirupma Singh Thakur Gurjeet Bedi Onkar 《Inflammation research》2021,70(7):765-776
Inflammation Research - Non-alcoholic fatty liver disease (NAFLD) is a multifaceted disease allied with various metabolic disorders, obesity and dysbiosis. Gut microbiota plays an influential role... 相似文献