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51.
Accumulating evidence has revealed that livin gene and BCL-2 modifying factor (BMF) gene are closely associated with the initiation and progression of colon carcinoma by activating or suppressing multiple malignant processes. Those genes that can detect colon - cancer are a promising approach for cancer screening and diagnosis. This study aimed to evaluate correlation between livin, BMF and p53 genes expression in colon cancer tissues of patients included in the study, and their relationship with clinicopathological features and survival outcome in those patients. In this study, 50 pathologically diagnosed early cancer colon patients included and their tissue biopsy with 50 matched adjacent normal tissue, and 50 adenoma tissue specimens were analyzed for livin gene and BMF gene expressions using real time PCR. The relationship of those genes expressions with clinicopathological features, tumor markers, Time to Progression and overall survival for those patients were correlated in cancer colon group. In this study, there was a significant a reciprocal relationship between over expression of livin gene and down regulation of BMF and p53 genes in colon cancer cells. Livin mRNA was significantly higher, while BMF and p53 mRNA were significantly lower in colorectal cancer tissue compared to benign and normal colon tissue specimens (P < 0.001), however, this finding was absent between colon adenomas and normal mucosa. There was a significant association between up regulation of livin and down regulation of BMF and p53 expressions with more aggressive tumor (advanced TNM stage), rapid progression with metastasis and decreased overall survival in cancer colon patients, hence these genes can serve as significant prognostic markers of poor outcome in colon cancer patients. This work highlights the role of livin, BMF and p53 genes in colorectal tumorigenesis and the applicability of using those genes as a diagnostic and prognostic markers in patients with colon carcinoma and as a good target for cancer colon treatment in the future.  相似文献   
52.
Insertion/deletion (I/D) polymorphism, of a 287-bp Alu repetitive sequence in intron 16 of the angiotensin-converting enzyme (ACE) gene has been shown to be associated with different types of diseases and has been widely investigated in different populations with different ethnic origins. Various reports were published suggesting inter-ethnic variations in the frequency of allelic forms of the ACE gene. The goal of this study was to test the distribution of alleles and the different genotypes of ACE (I/D) polymorphism in Bahraini subjects and compare the results with those obtained from other population studies. The Bahraini population is an Arabic peninsula population with a high prevalence of T2DM and hypertension. A total of 560 unrelated Bahraini individuals were recruited in this study and the presence (insertion)/absence (deletion) (I/D) polymorphism of a 287-bp Alu1 element inside intron 16 of the ACE gene was done by PCR-based assays and the presence or absence of the genotypes were analyzed by the gel electrophoresis. The distribution of II, ID, and DD genotypes showed differences among Bahraini subjects, and the frequency of the D allele was significantly (P < 0.05) higher in the studied group. The results obtained for the D allele are consistent with those obtained from previous studies among Arabs, Africans, and Caucasians, but differs significantly (P < 0.05) from those in Japanese and Chinese, thus proving the ethnic variation in the distribution of the ACE alleles in different populations.  相似文献   
53.
The properties of Trematosphaeria mangrovei laccase enzyme purified on Sephadex G-100 column were investigated. SDS–PAGE of the purified laccase enzyme showed a single band at 48 kDa. The pure laccase reached its maximal activity at temperature 65 °C, pH 4.0 with Km equal 1.4 mM and Vmax equal 184.84 U/mg protein. The substrate specificity of the purified laccase was greatly influenced by the nature and position of the substituted groups in the phenolic ring. The pure laccase was tested with some metal ions and inhibitors, FeSO4 completely inhibited laccase enzyme and also highly affected by (NaN3) at a concentration of 1 mM. Amino acid composition of the pure enzyme was also determined. Carbohydrate content of purified laccase enzyme was 23% of the enzyme sample. The UV absorption spectra of the purified laccase enzyme showed a single peak at 260–280 nm.  相似文献   
54.
S-(N-methylcarbamoyl)glutathione, a chemically-reactive glutathione conjugate, has been isolated from the bile of rats administered methyl isocyanate and characterized, as its N-benzyloxycarbonyl dimethylester derivative, by tandem mass spectrometry. The ability of this glutathione adduct to donate an N-methylcarbamoyl moiety to the free -SH group of cysteine was evaluated in vitro with the aid of a highly specific thermospray LC/MS assay procedure. The glutathione adduct reacted readily with cysteine in buffered aqueous media (pH 7.4, 37 degrees C) and after 2 hr, 42.5% of the substrate existed in the form of S-(N-methylcarbamoyl)cysteine. The reverse reaction, i.e. between the cysteine adduct and free glutathione, also took place readily under these conditions. It is concluded that conjugation of methyl isocyanate with glutathione in vivo affords a reactive S-linked product which displays the potential to carbamoylate nucleophilic amino acids. The various systemic toxicities associated with exposure of animals or humans to methyl isocyanate could therefore be due to release of the isocyanate from its glutathione conjugate, which thus may serve as a vehicle for the transport of methyl isocyanate in vivo.  相似文献   
55.
In spite of the many developments in synthetic oligonucleotide (ON) chemistry and design, invasion into double-stranded DNA (DSI) under physiological salt and pH conditions remains a challenge. In this work, we provide a new ON tool based on locked nucleic acids (LNAs), designed for strand invasion into duplex DNA (DSI). We thus report on the development of a clamp type of LNA ON—bisLNA—with capacity to bind and invade into supercoiled double-stranded DNA. The bisLNA links a triplex-forming, Hoogsteen-binding, targeting arm with a strand-invading Watson–Crick binding arm. Optimization was carried out by varying the number and location of LNA nucleotides and the length of the triplex-forming versus strand-invading arms. Single-strand regions in target duplex DNA were mapped using chemical probing. By combining design and increase in LNA content, it was possible to achieve a 100-fold increase in potency with 30% DSI at 450 nM using a bisLNA to plasmid ratio of only 21:1. Although this first conceptual report does not address the utility of bisLNA for the targeting of DNA in a chromosomal context, it shows bisLNA as a promising candidate for interfering also with cellular genes.  相似文献   
56.
Recently, we reported the therapeutic potential of mesenchymal stem/stromal cells (MSCs) from the maternal decidua basalis tissue of human term placenta (DBMSCs) to treat inflammatory diseases, such as atherosclerosis and cancer. DMSCs protect endothelial cell functions from the negative effects of oxidative stress mediators including hydrogen peroxide (H2O2) and monocytes. In addition, DBMSCs induce the generation of anti-cancer immune cells known as M1 macrophages. Diabetes is another inflammatory disease where endothelial cells are injured by H2O2 produced by high level of glucose (hyperglycaemia), which is associated with development of thrombosis. Here, we investigated the ability of DBMSCs to reverse the damaging effects of high levels of glucose on endothelial cells. DBMSCs and endothelial cells were isolated from human placental and umbilical cord tissues, respectively. Endothelial cells were incubated with glucose in presence of DBMSCs, and their functions were evaluated. The effect of DBMSCs on glucose- treated endothelial cell expression of genes was also determined. DBMSCs reversed the effects of glucose on endothelial cell functions including proliferation, migration, angiogenesis and permeability. In addition, DBMSCs modified the expression of several genes mediating essential endothelial cell functions including survival, apoptosis, permeability and angiogenesis. We report the first evidence that DBMSCs protect the functions of endothelial cells from the damaging effects of glucose. Based on these results, we establish that DBMSCs are promising therapeutic agents to repair glucose-induced endothelial cell injury in diabetes. However, these finding must be investigated further to determine the pathways underlying the protective role of DBMSCs on glucose-stimulated endothelial cell Injury.  相似文献   
57.
Gastric ulceration is a prevalent worldwide clinical presentation due to altered gastric defense mechanisms. Nonsteroidal anti-inflammatory drugs are one of the common causes of gastric ulcers mediated by the release of inflammatory mediators. The study aimed to investigate the potential protective effect of soyasaponin I (soya) against diclofenac (DIC)-induced gastric ulcer in rats and to highlight the underlying mechanisms. The experiment was conducted on 40 male Wistar albino rats, equally distributed into five groups: control, DIC-induced ulcer (9 mg/kg/d, orally, twice daily for 3 days), ulcer/soya-, ulcer/ranitidine-, and ulcer/soya/selective nuclear factor kappa B inhibitor (JSH-23)-treated groups. The doses of soya, ranitidine, and JSH were 20, 25, and 5 mg/kg/d, respectively, given orally. Gastric specimens were prepared for gene and histological study and for biochemical analysis of gastric prostaglandin E2 (PGE2), oxidative markers, and inflammatory cytokines. The gastric samples were formalin-fixed, paraffin-embedded, and subjected to hematoxylin and eosin (H&E), PAS staining, and immunohistochemical assay for identification of nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2), and proliferation marker (Ki67) expressions. The findings revealed decreased gastric PGE2 and altered inflammatory and oxidative markers in the ulcer model group. The H&E staining showed mucosal injury characterized by mucosal surface defects and inflammatory cell infiltrations. The polymerase chain reaction (PCR) and immunohistochemistry demonstrated an upregulation of NF-κB and COX-2 expression at gene/protein levels; meanwhile, Ki67 downregulation. The soya-treated group showed maintained biochemical, histological, and PCR findings comparable to the ranitidine-treated group. The JSH-23-treated group still showed partial gastric protection with biochemical and immunohistochemical changes. Soyasaponin I ameliorated DIC-induced gastric ulcers by targeting the COX-2 activity through modulation of NF-κB signaling.  相似文献   
58.
Glycerol production by a highly glycerol-producing local isolate (Eurotium amstelodami) and a standard reference isolate (Aspergillus wentii) was markedly enhanced by high saline media. Glycerol concentration depended on the external osmotic. Thus, the highest glycerol concentration was found in the presence of NaCl, followed by KCl, with considerably lower values for MgCl2 and CaCl2 saline media. With glucose (5–50%) used as a nonionic osmotic, low levels of glycerol were obtained and the main pool of polyols was mannitol. Glycerol production was gradually increased with the increase of NaCl concentration of cheese whey, reaching maxima by both organisms when whey was supplemented with 8% NaCl (total of 16% NaCl). The quantity of glycerol produced byA. wentii was twice higher than that obtained byE. amstelodami on whey treated with 8% NaCl.  相似文献   
59.
The small heat shock proteins (sHSPs) and the related α-crystallins (αCs) are virtually ubiquitous proteins that are strongly induced by a variety of stresses, but that also function constitutively in multiple cell types in many organisms. Extensive research has demonstrated that a majority of sHSPs and αCs can act as ATP-independent molecular chaperones by binding denaturing proteins and thereby protecting cells from damage due to irreversible protein aggregation. As a result of their diverse evolutionary history, their connection to inherited human diseases, and their novel protein dynamics, sHSPs and αCs are of significant interest to many areas of biology and biochemistry. However, it is increasingly clear that no single model is sufficient to describe the structure, function or mechanism of action of sHSPs and αCs. In this review, we discuss recent data that provide insight into the variety of structures of these proteins, their dynamic behavior, how they recognize substrates, and their many possible cellular roles.  相似文献   
60.
The objective was to determine the prevalence of iodine deficiency among hypothyroid patients and the effect of dietary goitrogens on indices of iodine and thyroid status. This is a case-control study of 106 subjects who were recruited from King Abdulaziz University Hospital, Jeddah. Blood and urine were collected for serum thyroid hormones, thyroid autoantibodies, thyroglobulin (Tg) and urinary iodine concentration (UIC). Dietary iodine and goitrogenic food intake were assessed by questionnaire. Using World Health Organization (WHO) cutoff values for UIC, both controls and cases were iodine deficient (85% and 83%, respectively). Furthermore, dietary iodine was deficient in 23% of controls and 36% of cases. In cases, there was a positive association between UIC levels and serum thyroid stimulating hormone (r = 0.405, p < 0.01) and a negative association with serum fT4 (r = −0.358, p < 0.01). Serum Tg antibody titers were also positively associated with dietary iodine (r = 0.328, p < 0.05). Patients with elevated serum autoantibodies had lower UIC and dietary iodine than those with normal serum autoantibodies. UIC was associated with dietary goitrogens including turnip (r = 0.280, p < 0.05) and pine (r = 0.289, p < 0.05) among cases. Iodine deficiency is common and the consumption of dietary goitrogens is high among euthyroid and hypothyroid subjects living in Jeddah.  相似文献   
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