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71.
Our knowledge about a link between buprenorphine and hepatotoxicity is controversial. This study evaluated the effects of buprenorphine on the liver of young, adult, and aged rats. For this reason, young, adult, and aged rats received intraperitoneally 0.25, 0.5, and 1 mg/kg buprenorphine for 30 days. The present results revealed that the normal aging was associated with a significant decrease in the activities of antioxidant enzymes, and an increase in the liver lipid peroxidation, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities in the aged rats. This study also demonstrated that buprenorphine led to a significant increase in the serum activities of ALT, AST, and LDH as well as liver lipid peroxidation content with a decrease in the antioxidant enzymes in the liver of buprenorphine‐treated aged rat versus the aged matched control animals. In conclusion, the present results demonstrate that buprenorphine deteriorated oxidative damage in the aged livers.  相似文献   
72.
Bone morphogenetic protein 4 (BMP4) and retinoic acid (RA) signaling are the key regulators for germ cell and meiosis induction, respectively. Gonadal tissue also provides an appropriate microenvironment for oocyte differentiation in vivo. The current study aimed to determine whether mimicking in vivo niche is more efficient for oocyte differentiation from embryonic stem (ES) cells. Here, differentiation of mouse ES cells toward oocyte‐like cells using embryoid body (EB) and monolayer protocols was induced in the presence (+BMP4) or absence (‐BMP4) of BMP4. On day 5, each group was co‐cultured with ovarian somatic cells in the presence or absence of RA (+RA or –RA) for an additional 14 days. Our results showed a significant increase in expression of meiotic markers in the +BMP4 condition in EB differentiation protocol. Further differentiation with ovarian somatic cells led to a subpopulation of oocyte‐like cell formation. Compared to the controls, the +RA condition resulted in a significant elevation of the meiotic gene expression in contrast to Oct4 that significantly decreased in both protocols. In the cells pre‐treated with BMP4 and then exposed to RA in the monolayer differentiation protocol, the gene expression levels of germ cell, Mvh, and maturation markers, Cx37, Zp2, and Gdf9, were also upregulated significantly. Therefore, it can be concluded that +BMP4 and +RA along with ovarian somatic cell co‐culture improved the rate of in vitro oocyte differentiation.  相似文献   
73.
74.
Responses of plants to salinity stress and the development of salt tolerance are extremely complex. Proteomics is a powerful technique to identify proteins associated with a particular environmental or developmental signal. We employed a proteomic approach to further understand the mechanism of plant responses to salinity in a salt-tolerant (Afzal) and a salt-sensitive (Line 527) genotype of barley. At the 4-leaf stage, plants were exposed to 0 (control) or 300 mM NaCl. Salt treatment was maintained for 3 weeks. Total proteins of leaf 4 were extracted and separated by two-dimensional gel electrophoresis. More than 500 protein spots were reproducibly detected. Of these, 44 spots showed significant changes to salt treatment compared to the control: 43 spots were upregulated and 1 spot was downregulated. Using MALDI-TOF-TOF MS, we identified 44 cellular proteins have been identified, which represented 18 different proteins and were classified into seven categories and a group with unknown biological function. These proteins were involved in various many cellular functions. Up regulation of proteins which involved in reactive oxygen species scavenging, signal transduction, protein processing and cell wall may increase plant adaptation to salt stress. The upregulation of the three of four antioxidant proteins (thioredoxin, methionine sulfoxide reductase and dehydroascorbate reductase) in susceptible genotype Line 527 suggesting a different tolerance mechanism (such as tissue tolerance) to tolerate a salinity condition in comparison with the salt sensitive genotype.  相似文献   
75.
Mechanical ventilation with hyperoxia is necessary to treat critically ill patients. However, prolonged exposure to hyperoxia leads to the generation of excessive reactive oxygen species (ROS), which can cause acute inflammatory lung injury. One of the major effects of hyperoxia is the injury and death of pulmonary epithelium, which is accompanied by increased levels of pulmonary proinflammatory cytokines and excessive leukocyte infiltration. A thorough understanding of the signaling pathways leading to pulmonary epithelial cell injury/death may provide some insights into the pathogenesis of hyperoxia-induced acute inflammatory lung injury. This review focuses on epithelial responses to hyperoxia and some of the major factors regulating pathways to epithelial cell injury/death, and proinflammatory responses on exposure to hyperoxia. We discuss in detail some of the most interesting players, such as NF-kappaB, that can modulate both proinflammatory responses and cell injury/death of lung epithelial cells. A better appreciation for the functions of these factors will no doubt help us to delineate the pathways to hyperoxic cell death and proinflammatory responses.  相似文献   
76.
In this research, biostratigraphy, microfacies analysis and sequence stratigraphic framework of the Asmari Formation are discussed at Sepidar Anticline, Interior Fars sub-Basin. The strata are Rupelian to Chattian in age. According to the distribution of benthic foraminifera, two assemblage zones were recognised (I-) Nummulites vascus–Nummulites fichteli and (II-) Archaias asmaricus/hensoni–Miogypsinoides complanatus. Eight microfacies types which can be grouped into three depositional environments are recognised. Distribution of Oligocene foraminifera together with other constituents allowed the identification of three third-order sequences at Asmari Formation. Correlation of analysed sections through Interior Fars sub-Basin represents the development of a carbonate ramp with a deepening trend from SE to NW along the Rupelian/Chattian boundary.  相似文献   
77.
Crocetin, the major carotenoid in saffron, exhibits potent anticancer effects. However, the antileukemic effects of crocetin are still unclear, especially in primary acute promyelocytic leukemia (APL) cells. In the current study, the potential antipromyelocytic leukemia activity of crocetin and the underlying molecular mechanisms were investigated. Crocetin (100 µM), like standard anti-APL drugs, all-trans retinoic acid (ATRA, 10 µM) and As2O 3 (arsenic trioxide, 50 µM), significantly inhibited proliferation and induced apoptosis in primary APL cells, as well as NB4 and HL60 cells. The effect was associated with the decreased expressions of prosurvival genes Akt and BCL2, the multidrug resistance (MDR) proteins, ABCB1 and ABCC1 and the inhibition of tyrosyl-DNA phosphodiesterase 1 (TDP1), while the expressions of proapoptotic genes CASP3, CASP9, and BAX/BCL2 ratio were significantly increased. In contrast, crocetin at relatively low concentration (10 µM), like ATRA (1 µM) and As 2O 3 (0.5 µM), induced differentiation of leukemic cells toward granulocytic pattern, and increased the number of differentiated cells expressing CD11b and CD14, while the number of the immature cells expressing CD34 or CD33 was decreased. Furthermore, crocetin suppressed the expression of clinical marker promyelocytic leukemia/retinoic acid receptor-α ( PML/RARα) in NB4 and primary APL cells, and reduced the expression of histone deacetylase 1 ( HDAC1) in all leukemic cells. The results suggested that crocetin can be considered as a candidate for future preclinical and clinical trials of complementary APL treatment.  相似文献   
78.
Herbarium specimens are a treasure trove for biochemical studies. However, this implies understanding of the chemical changes during the drying and storage of the specimen. We compared herbarium specimens at different ages and fresh samples of four mushroom species (Kuehneromyces mutabilis, Hypholoma capnoides, Kuehneromyces lignicola, Hypholoma fasciculare) of two genera in the family Strophariaceae by using proton nuclear magnetic resonance (1H NMR) spectroscopy combined with principal component analysis (PCA). 25 metabolites were identified. No significant alterations were found between herbarium samples at different ages, suggesting that they are stable enough for comparative studies. The most dominant differences between fresh and herbarium samples was that sugars such as α-α-trehalose, and fumaric and malic acids were more abundant in fresh fungi. Total contents of fatty and amino acids, uracil and γ-aminobutyric acid (GABA) were higher in herbarium specimens. In addition, pyroglutamic acid was observed only in Kuehneromyces mutabilis and fasciculic acid E in Hypholomafasciculare. Hence, based on results of the studied taxa, we conclude that NMR metabolomics can be used for both fresh and dried mushrooms when such alterations are properly addressed.  相似文献   
79.
Hepatitis C virus (HCV) infection is a major public health problem with about 1.75 million new HCV cases and 71 million chronic HCV infections worldwide. The study aimed to evaluate clinical, serological, molecular, and liver markers to develop a mathematical predictive model for the quantification of the HCV viral load in chronic HCV infected patients. In this cross‐sectional study, blood samples were taken from 249 recently diagnosed HCV‐infected subjects and were tested for liver condition, viral genotype, and HCV RNA load. Receiver operating characteristics (ROC) curves and multiple linear regression analysis were used to predict the HCV‐RNA load. Genotype 3 followed by genotype 1 were the most prevalent genotypes in Mashhad, Northeastern Iran. The maximum levels of viral load were detected in the mixed genotype group, and the lowest levels in the undetectable genotype group. The log of the HCV viral load was significantly associated with thrombocytopenia and higher serum levels of alanine transaminase (ALT). In addition, the log HCV RNA was significantly higher in patients with arthralgia, fatigue, fever, vomiting, or dizziness. Moreover, genotype 3 was significantly associated with icterus. A ROC curve analysis revealed that the best cut‐off points for serum levels of aspartate aminotransferase (AST), ALT, and alkaline phosphatase (ALP) were >31, >34, and ≤246 IU/L, respectively. Sensitivity, specificity, and positive predictive values for AST were 87.7%, 84.36%, and 44.6%, for ALT they were 83.51%, 81.11%, and 36%, and for ALP were 72.06%, 42.81%, and 8.3%, respectively. A mathematical regression model was developed that could estimate the HCV‐RNA load. Regression model: log viral load = 7.69 ? 1.01 × G3 ? 0.7 × G1 + 0.002 × ALT ? 0.86 × fatigue.  相似文献   
80.
Generation of patient specific stem cells is among the ultimate goals in regenerative medicine. Such a cell needs to be functional when it transplants. Interaction between the matrix proteins and integrin adjust many cells' function such as adhesion, migration, cell cycle and self renewal in stem cells. In this study, NIH3T3 cells were dedifferentiated by mouse Embryonic Stem Cell (mESC) extract. The expression of pluripotency markers as well as a2, a5 and a6 integrin subunits were determined. NIH3T3 cells treated with mESC extract showed noticeable changes in cell morphology as early as day 2 post-treatment forming colonies similar to typical mESC morphology by day 8, after three passages. Alkaline phosphatase (ALP) assay and immunocytochemistry staining were performed for the induced reprogrammed cells. The results indicated that these colonies showed the ALP activity and they express Sox2 and Nanog. RT-PCR revealed that the colonies also express Oct3/4. NIH3T3 cells, ESC and reprogrammed cells expressed a2 integrin. a5 integrin expression was greatest in reprogrammed cells followed by the expression of this integrin in NIH3T3 which in turn was more than in ESC. a6A integrin was expressed in NIH3T3 cells while a6B integrin was expressed in ESC and in very low quantity was expressed in reprogrammed cells. These data provide evidence for both the generation of ES like cells from differentiated somatic cells and the expression profile of integrins after de-differentiation by mESC extract.  相似文献   
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