AIM: To study the alterations in p53 gene among Indian gastric cancer patients and to correlate them with the various clinicopathological parameters. METHODS: A total of 103 gastric cancer patients were included in ...AIM: To study the alterations in p53 gene among Indian gastric cancer patients and to correlate them with the various clinicopathological parameters. METHODS: A total of 103 gastric cancer patients were included in this study. The p53 alterations were studied by both immunohistochemical method as well as polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. We only studied four (exon 5, 6, 7, and 8) of the 11 ,p53 exons. The alterations in p53 were also correlated with respect to various clinicopathological parameters. RESULTS: Among 103 cases, p53 over-expression and alteration were detected in 37 (35.92%) and 19 (18.44%) cases, respectively. Most of the ,p53 alterations were found at exon 5 (31.54%), followed by exon 6 (26.31%), exon 7 (21.04%) and exon 8 (21.04%). A significant correlation of p53 overexpression was found with p53 alteration (P = 0.000). Concordance between ,p53 alteration (as detected by SSCP) and over-expression [as detected by immunohistochemistry (IHC)] was found in 75% cases. We found that IHC-positive/SSCP-negative cases accounted for 21% of cases and IHC-negative/SSCP- positive cases accounted for remaining 4% cases. CONCLUSION: Our results show that p53 gene mutations are significantly correlated with p53 protein over-expression, with 75% concordance in over-expression and alteration in the p53 gene, but 25% disconcordance also cautions against the assumption that p53 over-expression is always associated with a gene mutation. There may be other mechanisms responsible for stabilization and accumulation of p53 protein with no evidence of gene mutation that reflect an accumulation of a non-mutated protein, or a false negative SSCP result.展开更多
Tea (Camellia sinensis) is one of the most important economic crops. Being perennial in nature, tea plant often experiences natural drought, which affects its growth and productivity. The present investigation was und...Tea (Camellia sinensis) is one of the most important economic crops. Being perennial in nature, tea plant often experiences natural drought, which affects its growth and productivity. The present investigation was undertaken to understand the mechanism of post-drought stress recovery on rehydration and the effect of nutrients in the recovery process of the selected clones of Camellia sinensis L. (TV-1, TV-20, TV-29 & TV-30). The results demonstrated that decrease in relative water content (RWC), dry mass of leaf and antioxidants like-ascorbate and glutathione in all the tested clones, as a result of imposed water stress, which caused damage was not permanent. Increase in phenolic content with decrease in O2-, H2O2 and lipid peroxidation was indication of the recovery of stress induced oxidative damage following the post stress rehydration. Further, the post drought recovery was enhanced by foliar spray of K, Ca, Mn & B. Differential activities of enzymes like SOD, CAT, POX, GR and PPO in response to foliar spray of nutrients in rehydrated plant improved the recovery process. The present study reveals that the tested nutrients (K, Ca, Mn & B) showed some positive response in influencing growth and antioxidative responses during post drought recovery process, where K and Ca showed comparatively better effect in improving post drought recovery potential in tea plant.展开更多
Heparin is a negatively charged polysaccharide with various chain lengths and a hydrophilic backbone.Due to its fascinating chemical and physical properties,nontoxicity,biocompatibility,and biodegradability,heparin ha...Heparin is a negatively charged polysaccharide with various chain lengths and a hydrophilic backbone.Due to its fascinating chemical and physical properties,nontoxicity,biocompatibility,and biodegradability,heparin has been extensively used in different fields of medicine,such as cardiovascular and hematology.This review highlights recent and future advancements in designing materials based on heparin for various biomedical applications.The physicochemical and mechanical properties,biocompatibility,toxicity,and biodegradability of heparin are discussed.In addition,the applications of heparin-based materials in various biomedical fields,such as drug/gene delivery,tissue engineering,cancer therapy,and biosensors,are reviewed.Finally,challenges,opportunities,and future perspectives in preparing heparin-based materials are summarized.展开更多
文摘AIM: To study the alterations in p53 gene among Indian gastric cancer patients and to correlate them with the various clinicopathological parameters. METHODS: A total of 103 gastric cancer patients were included in this study. The p53 alterations were studied by both immunohistochemical method as well as polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. We only studied four (exon 5, 6, 7, and 8) of the 11 ,p53 exons. The alterations in p53 were also correlated with respect to various clinicopathological parameters. RESULTS: Among 103 cases, p53 over-expression and alteration were detected in 37 (35.92%) and 19 (18.44%) cases, respectively. Most of the ,p53 alterations were found at exon 5 (31.54%), followed by exon 6 (26.31%), exon 7 (21.04%) and exon 8 (21.04%). A significant correlation of p53 overexpression was found with p53 alteration (P = 0.000). Concordance between ,p53 alteration (as detected by SSCP) and over-expression [as detected by immunohistochemistry (IHC)] was found in 75% cases. We found that IHC-positive/SSCP-negative cases accounted for 21% of cases and IHC-negative/SSCP- positive cases accounted for remaining 4% cases. CONCLUSION: Our results show that p53 gene mutations are significantly correlated with p53 protein over-expression, with 75% concordance in over-expression and alteration in the p53 gene, but 25% disconcordance also cautions against the assumption that p53 over-expression is always associated with a gene mutation. There may be other mechanisms responsible for stabilization and accumulation of p53 protein with no evidence of gene mutation that reflect an accumulation of a non-mutated protein, or a false negative SSCP result.
文摘Tea (Camellia sinensis) is one of the most important economic crops. Being perennial in nature, tea plant often experiences natural drought, which affects its growth and productivity. The present investigation was undertaken to understand the mechanism of post-drought stress recovery on rehydration and the effect of nutrients in the recovery process of the selected clones of Camellia sinensis L. (TV-1, TV-20, TV-29 & TV-30). The results demonstrated that decrease in relative water content (RWC), dry mass of leaf and antioxidants like-ascorbate and glutathione in all the tested clones, as a result of imposed water stress, which caused damage was not permanent. Increase in phenolic content with decrease in O2-, H2O2 and lipid peroxidation was indication of the recovery of stress induced oxidative damage following the post stress rehydration. Further, the post drought recovery was enhanced by foliar spray of K, Ca, Mn & B. Differential activities of enzymes like SOD, CAT, POX, GR and PPO in response to foliar spray of nutrients in rehydrated plant improved the recovery process. The present study reveals that the tested nutrients (K, Ca, Mn & B) showed some positive response in influencing growth and antioxidative responses during post drought recovery process, where K and Ca showed comparatively better effect in improving post drought recovery potential in tea plant.
基金funding from the National Institutes of Health(4UG3TR003148-02,and 5R01AR073135-06)the Terasaki Institute for Biomedical Innovation.
文摘Heparin is a negatively charged polysaccharide with various chain lengths and a hydrophilic backbone.Due to its fascinating chemical and physical properties,nontoxicity,biocompatibility,and biodegradability,heparin has been extensively used in different fields of medicine,such as cardiovascular and hematology.This review highlights recent and future advancements in designing materials based on heparin for various biomedical applications.The physicochemical and mechanical properties,biocompatibility,toxicity,and biodegradability of heparin are discussed.In addition,the applications of heparin-based materials in various biomedical fields,such as drug/gene delivery,tissue engineering,cancer therapy,and biosensors,are reviewed.Finally,challenges,opportunities,and future perspectives in preparing heparin-based materials are summarized.