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31.
Reviews in Environmental Science and Bio/Technology - In the past few decades, pollution from microplastics has emerged as an important issue on a global scale. These plastic particles are mainly...  相似文献   
32.
Inositol hexaphosphate (IP6) is a natural constituent found in almost all cereals and legumes. It is known to cause numerous antiangiogenic manifestations. Notwithstanding its great potential, it is underutilized due to the chelation and rapid excretion from the body. Jacalin is another natural constituent obtained from seeds of jackfruit and can target disaccharides overexpressed in tumor cells. The current study was in-quested to develop and evaluate a surface-modified gold nanoparticulate system containing IP6 and jacalin which may maximize the apoptotic effect of IP6 against HCT-15 cell lines. IP6 loaded jacalin-pectin-gold nanoparticles (IJP-GNPs) were developed through reduction followed by incubation method. The developed formulation was tested for various in vitro and in silico studies to investigate its potential. HCT-15 cells when exposed to IJP-GNP resulted in significant apoptotic effects in dose as well as time-dependent manner, as measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, micronucleus, and reactive oxygen species assay. IJP-GNP displayed cell cycle arrest at the G0/G1 phase. To further explore the mechanism of chemoprevention, in silico studies were performed. The docking results revealed that the interactive behavior of IP6, P-GNP, and jacalin could target and inhibit the tumor formation activity, supported by in vitro studies. Taken together, all the findings suggested that IP6 loaded nanoparticles may increase the hope of future drug delivery strategy for targeting colon cancer.  相似文献   
33.
The morphology and number of cells in the trophectoderm (TE) and inner cell mass (ICM) of buffalo blastocysts derived from in vitro fertilization and cultured in the presence or absence of insulin-like growth factor-I (IGF-I) were analyzed by differential fluorochrome staining technique. The total cell number (TCN), TE number, and ICM cell number were significantly higher in blastocysts developed in vitro in the presence of IGF-I as compared to blastocysts developed without IGF-I (P < 0.01). It was observed that the buffalo blastocyst took 5–9 days postfertilization to develop in vitro. In order to correlate the time required for blastocyst development and the allocation of cells to TE and ICM, blastocysts were designated as fast (developing on or before day 7) or slow (developing after day 7). The TCN, TE, and ICM cells of fast-developing blastocysts cultured in the presence of IGF-I were significantly higher than slow-developing blastocysts (P < 0.01). The blastocysts developed on day 6 had a mean total cell number 118.6 ± 21.4, which significantly decreased to 85.6 ± 17.4, 62.0 ± 14.5, and 17.0 ± 4.0 on days 7, 8, and 9, respectively (P < 0.05). Normal development of buffalo embryo showed that, on average, embryos reached compact morula stage at the earliest between days 4.5–5.5. Blastocysts developed, at the earliest, between days 5.0–6.0, and it took them, on average, 6.5 days to hatch from the zona pellucida. TCN, TE, and ICM increased three times from morula to blastocyst; however, the proportion of ICM to TCN remained the same, in both embryonic stages. TE approximately doubled in hatched blastocysts, as compared to unhatched blastocysts (P < 0.05). However, ICM cells were decreased. The time required for development of parthenogenetic blastocysts was observed to be greater as compared to in vitro fertilized (IVF) blastocysts. The total cell number of parthenogenetic blastocysts was 100.8 ± 11.3, including 59.2 ± 8.4 cells of TE and 42.1 ± 6.9 cells of ICM. © 1996 Wiley-Liss, Inc.  相似文献   
34.
Endoplasmic reticulum (ER) dysfunction plays a prominent role in the pathophysiology of diabetic nephropathy (DN). This study aimed to investigate the novel role of Naringenin (a flavanone mainly found in citrus fruits) in modulating ER stress in hyperglycemic NRK 52E cells and STZ/nicotinamide induced diabetes in Wistar rats. The results demonstrated that Naringenin supplementation downregulated the expression of ER stress marker proteins, including p-PERK, p-eIF2α, XBP1s, ATF4 and CHOP during hyperglycemic renal toxicity in vitro and in vivo. Naringenin abrogated hyperglycemia-induced ultrastructural changes in ER, evidencing its anti-ER stress effects. Interestingly, treatment of Naringenin prevented nuclear translocation of ATF4 and CHOP in hyperglycemic renal cells and diabetic kidneys. Naringenin prevented apoptosis in hyperglycemic renal cells and diabetic kidney tissues by downregulating expression of apoptotic marker proteins. Further, photomicrographs of TEM confirmed anti-apoptotic potential of Naringenin as it prevented membrane blebbing and formation of apoptotic bodies in hyperglycemic renal cells. Naringenin improved glucose tolerance, restored serum insulin level and reduced serum glucose level in diabetic rats evidencing its anti-hyperglycemic effects. Histopathological examination of kidney tissues also confirmed prevention of damage after 28 days of Naringenin treatment in diabetic rats. Additionally, Naringenin diminished oxidative stress and improved antioxidant defense response during hyperglycemic renal toxicity. Taken together, our study revealed a novel role of Naringenin in ameliorating ER stress during hyperglycemic renal toxicity along with prevention of apoptosis, cellular and tissue damage. The findings suggest that prevention of ER stress can be exploited as a novel approach for the management of hyperglycemic nephrotoxicity. Supplementary InformationThe online version contains supplementary material available at 10.1007/s12079-021-00644-0.  相似文献   
35.
36.
Lung cancer is the number one cause of cancer death; however, no specific serum biomarker is available till date for detection of early lung cancer. Despite good initial response to chemotherapy, small-cell lung cancer (SCLC) has a poor prognosis. Therefore, it is important to identify molecular markers that might influence survival and may serve as potential therapeutic targets. The review aims to summarize the current knowledge of serum biomarkers in SCLC to improve diagnostic efficiency in the detection of tumor progression in lung cancer. The current knowledge on the known serum cytokines and tumor biomarkers of SCLC is emphasized. Recent findings in the search for novel diagnostic and therapeutic molecular markers using the emerging genomic technology for detecting lung cancer are also described. It is believed that implementing these new research techniques will facilitate and improve early detection, prognostication and better treatment of SCLC.  相似文献   
37.
Inactivation of p53 is one of the most frequent molecular events in neoplastic transformation. Approximately 60% of all human tumors have mutations in both p53 alleles. Wild-type p53 activity is regulated in large part by the proteosome-dependent degradation of p53, resulting in a short p53 half-life in unstressed and untransformed cells. Activation of p53 by a variety of stimuli, including DNA damage induced by genotoxic drugs or radiation, is accomplished by stabilization of wild-type p53. The stabilized and active p53 can result in either cell-cycle arrest or apoptosis. Surprisingly, the majority of tumor-associated, inactivating p53 mutations also result in p53 accumulation. Thus, constitutive elevation of p53 levels in cells is a reliable measure of p53 inactivation, whereas transiently increased p53 levels reflect a recent genotoxic stress. In order to facilitate noninvasive imaging of p53 accumulation, we here describe the construction of a p53-luciferase fusion protein. Induction of DNA damage in cells expressing the fusion protein resulted in a time-dependent accumulation of the fusion that was noninvasively detected using bioluminescence imaging and validated by Western blot analysis. The p53-Luc protein retains p53 function because its expression in HCT116 cells lacking functional p53 resulted in activation of p21 expression as well as induction of apoptosis in response to a DNA damaging event. Employed in a transgenic animal model, the proposed p53-reporter fusion protein will be useful for studying p53 activation in response to exposure to DNA-damaging carcinogenic agents. It could also be used to study p53 stabilization as a result of inactivating p53 mutations. Such studies will further our understanding of p53's role as the "guardian of the genome" and its function in tumorigenesis.  相似文献   
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39.
A cDNA encoding a human ortholog of mouse DNA helicase B, which may play a role in DNA replication, has been cloned and expressed as a recombinant protein. The predicted human DNA helicase B (HDHB) protein contains conserved helicase motifs (superfamily 1) that are strikingly similar to those of bacterial recD and T4 dda proteins. The HDHB gene is expressed at low levels in liver, spleen, kidney, and brain and at higher levels in testis and thymus. Purified recombinant HDHB hydrolyzed ATP and dATP in the presence of single-stranded DNA, displayed robust 5'-3' DNA helicase activity, and interacted physically and functionally with DNA polymerase alpha-primase. HDHB proteins with mutations in the Walker A or B motif lacked ATPase and helicase activity but retained the ability to interact with DNA polymerase alpha-primase, suggesting that the mutants might be dominant over endogenous HDHB in human cells. When purified HDHB protein was microinjected into the nucleus of cells in early G(1), the mutant proteins inhibited DNA synthesis, whereas the wild type protein had no effect. Injection of wild type or mutant protein into cells at G(1)/S did not prevent DNA synthesis. The results suggest that HDHB function is required for S phase entry.  相似文献   
40.
Molecular variability among seven cultivars of A. deliciosa var. deliciosa was investigated through RAPD markers. Thirty four decamer primers were screened generating polymorphic patterns of amplified DNA for these cultivars. Twenty one selected primers gave clear and reporducible patterns. A total of 430 bands were produced and 29.37% of them were polymorphic. The patterns distinguished between the cultivars and their analysis established an approach to classification within A. deliciosa var. deliciosa based on RAPD markers. The dendrogram clearly differentiated male from female cultivars. While abbot and allison female cultivars were closely related, bruno and abbot female cultivars showed maximum dissimilarity.  相似文献   
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