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51.
Vivechana Dixit Jagdish Tewari S. Kay Obendorf 《Archives of environmental contamination and toxicology》2010,59(3):417-423
Antifungal properties were introduced in nonwoven regenerated cellulose (RC) nanofibrous membrane using Quillaja saponin. To generate cellulose membranes, deacetylation of electrospun cellulose acetate (CA) nanofibrous membranes was performed using 0.05 M NaOH and ethanol for membranes both loaded and unloaded with Quillaja saponin. Chemical and physical properties of nonwoven CA and RC nanofibrous membrane were characterized using scanning electron microscopy, attenuated total reflectance–Fourier transform infrared spectroscopy, differential scanning calorimetry, and tensile properties. Our results showed that saponin doping did not affect the morphology of the resulting fibers and that the membrane structure was maintained during deacetylation. The antifungal properties of saponin-loaded fabric were determined at 0 and 24 h against two household fungi, Penicillium roguefortii and Aspergillus ochraceus, and compared with control samples. Our findings show that after 24 h the saponin-loaded fabrics had spores kill of 80.4% and 53.6% for P. roguefortii and A. ochraceus, respectively. Fabric containing Quillaja saponin has potential for household applications and could be evaluated further for medical applications. 相似文献
52.
Priti Azad Tsering Stobdan Dan Zhou Iain Hartley Ali Akbari Vineet Bafna Gabriel G Haddad 《Journal of molecular medicine (Berlin, Germany)》2017,95(12):1269-1282
About 1.2 to 33% of high-altitude populations suffer from Monge’s disease or chronic mountain sickness (CMS). Number of factors such as age, sex, and population of origin (older, male, Andean) contribute to the percentage reported from a variety of samples. It is estimated that there are around 83 million people who live at altitudes > 2500 m worldwide and are at risk for CMS. In this review, we focus on a human “experiment in nature” in various high-altitude locations in the world—namely, Andean, Tibetan, and Ethiopian populations that have lived under chronic hypoxia conditions for thousands of years. We discuss the adaptive as well as mal-adaptive changes at the genomic and physiological levels. Although different genes seem to be involved in adaptation in the three populations, we can observe convergence at genetic and signaling, as well as physiological levels. What is important is that we and others have shown that lessons learned from the genes mined at high altitude can be helpful in better understanding and treating diseases that occur at sea level. We discuss two such examples: EDNRB and SENP1 and their role in cardiac tolerance and in the polycythemic response, respectively. 相似文献
53.
During an ultrasound-guided axillary brachial plexus block, sonoanatomy demonstrated a delayed formation of the lateral root to the median nerve from the lateral cord, an accessory coracobrachialis brevis muscle, and a course of the lateral root to the median nerve ‘spiralling’ around the accessory muscle prior to locating lateral to the brachial artery. This rare variant is further discussed in the context of median, musculocutaneous and coracobrachialis variations. 相似文献
54.
We studied HER-2/neu (HER-2) and topoisomerase IIa (topo2a) amplification (using chromogenic in situ hybridization) and overexpression (immunohistochemical analysis) in 113 invasive breast carcinomas. A gene copy number/chromosome 17 copy number ratio of 2.0 or higher indicated amplification. A topo2a/chromosome 17 ratio of less than 0.8 indicated gene deletion. HER-2 overexpression was scored according to standard HercepTest guidelines (DAKO, Carpinteria, CA). Overexpression of topo2a was identified when nuclear staining was found in more than 5% of tumor cells. Of 113 tumors, 104 were analyzed successfully for HER-2 and topo2a amplification. Of the 104, 64 showed HER-2 amplification; 25 of these (39%) also showed topo2a amplification. No amplification was found in 40 tumors. Deletion of topo2a was seen in 7 (11%) of 64 HER-2-amplified tumors and 2 (5%) of 40 nonamplified tumors. Of 25 tumors with topo2a amplification, 18 (72%) overexpressed topo2a. Only 3 (4%) of 79 tumors without topo2a amplification overexpressed topo2a. Amplification of topo2a is associated with HER-2 amplification but not vice versa. Amplification of topo2a resulted in protein overexpression in 72% of tumors, but topo2a overexpression rarely occurred without gene amplification. Identification of topo2a and HER-2 status might have therapeutic and prognostic implications. 相似文献
55.
We compared chromogenic in situ hybridization (CISH) with fluorescence in situ hybridization (FISH) for assessing HER-2/neu gene amplification using tissue microarrays (TMAs) made from formalin-fixed, paraffin-embedded tissue blocks from 113 cases of invasive breast carcinoma. TMAs were created using 0.6-mm tissue cores with 4 sampled cores per tumor. For both assays, a HER-2/chromosome 17 signal ratio of 2.0 or more was considered positive for gene amplification. The average ratio of cores from the same tumor was used for determination of gene amplification status of that particular tumor Of 113 cases, 102 were tested successfully by both assays. The results were concordant in 100.0% of cases (63 amplified; 39 nonamplified). All 22 cases of borderline (ratio, 2.0-2.5) or low-level (ratio, 2.6-3.9) amplification by FISH also showed HER-2 gene amplification by CISH. CISH is as sensitive as FISH in detecting borderline and low-level HER-2 amplification. Reliable recognition of the invasive carcinoma area by light microscopy and preservation of the test slides are added advantages of CISH. CISH performs as well as FISH in the analysis of HER-2 gene amplification in breast cancer and might have advantages in certain situations. 相似文献
56.
Patel T Bansal R Trivedi P Modi L Shah MJ 《Indian journal of pathology & microbiology》2005,48(4):482-484
Metastasis of mesothelioma of the pleura, to the skin and subcutis is an extremely rare occurrence. A 25 year old woman, who had undergone chemotherapy, partial excision of tumor followed by radiotherapy of sarcomatoid mesothelioma of the pleura, presented three months later with painless widespread subcutaneous nodules. FNAC of these nodules reveled pleomorphic malignant spindle shaped cell with epithelioid morphology. The subcutis is a particularly rare site of metastatic sarcomatoid mesothelioma. It is essential to differentiate neoplasm metastatic to the skin and subcutis from primary and benign lesions of the same region. FNAC is accurate and efficient, in conjugation with clinical history, and it also prevents surgical biopsy in the diagnosis of metastatic subcutaneous lesion. To our knowledge, this is the first case, reported till date, in which the sarcomatoid mesothelioma metastasized to the subcutaneous tissue and was diagnosed by fine needle aspiration cytology (FNAC). 相似文献
57.
The present communication focuses on molecular characterization of Fasciola gigantica isolates derived from cattle, buffalo, and goat using random-amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR) analysis to elucidate genetic variability between the three isolates. Seventeen random oligonucleotide primers of 10-11 bases with GC content varying from 50-81.8% were used in the study. Depending upon the F. gigantica isolate-primer combination, one to five fragments in the range of 327-1,973 bp were amplified. It was significant to observe that, out of the 17 primers directing amplification of DNA fingerprints, only two designated as AP9 and AP14 were found to be of potential interest in the generation of polymorphic DNA. On the basis of similarity coefficient data, it may be suggested that cattle and buffalo isolates of F. gigantica show 100% homogeneity against 92.68% similarity coefficient observed between goat and cattle/buffalo isolates. In other words, 7.32% divergence was observed between goat and cattle/buffalo isolates while the primers AP1, AP4, AP10, AP13, and AP17 were able to generate monomorphic DNA fingerprints. Primers AP9 and AP14 are potentially informative in terms of the polymorphic nature of the fingerprints generated in RAPD assays. The finding of the absence of 626-bp DNA fragment in the goat and the uniqueness of the AP14 in generating a single RAPD-PCR product of 1,211 bp as against the product size of 1,162 bp in cattle/buffalo seem to be significant. This is the first report of elucidation of RAPD-PCR based molecular variability in the DNA fingerprinting pattern of F. gigantica isolated from cattle, buffalo, and goat. 相似文献
58.
Tissue microarrays (TMAs) have been commonly used to study protein expression by immunohistochemistry (IHC). However, limited data exist on the validity of using TMAs to study gene amplification. In this study, we evaluated the feasibility of using breast carcinoma TMAs to study HER-2 gene amplification by fluorescence in situ hybridization (FISH). In addition, hormonal receptor status (ER and PR) and HER-2 protein overexpression by IHC were also studied, and results were compared with whole tissue sections. FISH for HER-2 was performed on formalin-fixed paraffin-embedded tissue from 114 invasive breast carcinomas both on whole tissue sections and on TMAs containing the same tumors. The TMA was created using 0.6-mm tissue cores with four sampled cores per tumor from the same tissue block used for whole section FISH. The PathVysion HER-2 probe kit was used for the FISH analysis. A ratio of HER-2:Chromosome17 > or =2.0 was interpreted as positive for gene amplification. The ER or PR was interpreted as positive when nuclear staining was detected in more than 10% of tumor cells. The HER-2 IHC (HercepTest; DAKO Corp, Carpinteria, CA) results were interpreted as 0, 1+, 2+, and 3+ according to standard criteria. The FISH results in the TMA and whole sections were concordant in 99 out of 101 successfully analyzed cases (99%). The FISH scores were consistent among the two to four cores in the majority of the cases. ER and PR results were concordant between whole sections and TMA cores in 97% (107/110) and 89% (97/109) cases, respectively. The overall concordance for HER-2 status by IHC between whole sections and TMA cores was 86% (94 out of 109 cases). TMAs are a reliable approach to study HER-2 gene amplification in a high throughput manner. 相似文献
59.
Objective
To investigate disparities in the frequency of ovarian cancer-related surgical procedures and access to high-volume surgical providers among women undergoing initial surgery for ovarian cancer according to race.Methods
The California Office of Statewide Health Planning and Development database was accessed for women undergoing a surgical procedure that included oophorectomy for a malignant ovarian neoplasm between 1/1/06 and 12/31/10. Multivariate logistic regression analyses were used to evaluate differences in the odds of selected surgical procedures and access to high-volume centers (hospitals ≥ 20 cases/year) according to racial classification.Results
A total of 7933 patients were identified: White = 5095 (64.2%), Black = 290 (3.7%), Hispanic/Latino =1400 (17.7%), Asian/Pacific Islander = 836 (10.5%) and other = 312 (3.9%). White patients served as reference for all comparisons. All minority groups were significantly younger (Black mean age 57.7 years, Hispanic 53.2 years, Asian 54.5 years vs. 61.1 years, p < 0.01). Hispanic patients had lower odds of obtaining care at a high-volume center (adjusted OR (adj. OR) = 0.72, 95% CI = 0.64–0.82, p < 0.01) and a lower likelihood of lymphadenectomy (adj. OR = 0.80, 95% CI = 0.70–0.91, p < 0.01), bowel resection (adj. OR = 0.80, 95% CI = 0.71–0.91, p < 0.01), and peritoneal biopsy/omentectomy (adj. OR = 0.69, 95% CI = 0.58–0.82, p < 0.01). Black racial classification was associated with a lower likelihood of lymphadenectomy (adj. OR = 0.76, 95% CI = 0.59–0.97, p = 0.03).Conclusions
Among women undergoing initial surgery for ovarian cancer, Hispanic patients are significantly less likely to be operated on at a high-volume center, and both Black and Hispanic patients are significantly less likely to undergo important ovarian cancer-specific surgical procedures compared to White patients. 相似文献60.