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121.
Mustafa Akker Sibel Güldiken Tammam Sipahi Orkide Palabıyık Ayhan Tosunoğlu Özlem Çelik Nermin Tunçbilek Atakan Sezer Necdet Süt 《Molecular biology reports》2014,41(5):3541-3547
We aimed to investigate insulin receptor substrate-1 (IRS-1), insulin receptor substrate-2 (IRS-2), insulin-like growth factor binding protein-3 (IGFBP-3) genotypes, which are thought to be involved in the pathogenesis of many solid tumors and have thus far not been studied in patients with differentiated thyroid cancer (DTC). The study consisted of 93 patients diagnosed with DTC (79 females, 14 males) and 111 healthy control subjects (63 females, 48 males). The anthropometric measurements, lipid profiles, thyroid function tests and homeostatic model assessment (HOMA) as an indicator of insulin resistance (IR) of all patients were recorded. In addition IRS-1, IRS-2 and IGFBP-3 gene polymorphisms were determined by using polymerase chain reaction and restriction fragment length polymorphism. Hardy–Weinberg equilibrium was tested for each gene polymorphisms, and genetic effects were evaluated by the Chi Square test and multiple logistic regression. Homeostasis model assessment of insulin resistance (HOMA-IR), body mass index, waist circumference and serum total cholesterol levels were significantly higher in patients with DTC than in the control group. There was no difference between the two groups with respect to IRS-1, IRS-2 and IGFBP-3 gene polymorphisms. In addition, these gene polymorphisms were found to have no effect on lymph node metastases or tumor staging. While, obesity and increased HOMA-IR may be risk factors in DTC development, we suggest that IRS-1, IRS-2 and IGFBP-3 gene polymorphisms do not play an important role in pathogenesis of DTC. 相似文献
122.
Kyaw W. Naing Muhammad Anees Xuan H. Nguyen Yong S. Lee Seung W. Jeon Sang J. Kim Myung H. Kim Kil Y. Kim 《Journal of Phytopathology》2014,162(6):367-376
For field application of a bacterial strain used to control Phythophthora capsici, we will need a biologically and economically efficient carrier medium. The known antagonist Paenibacillus ehimensisKWN38 was grown in a grass medium where it showed high antifungal and lytic enzyme activities. To demonstrate the potential of P. ehimensisKWN38 for biocontrol of late blight disease in pepper, pot trials were conducted by treating the 1‐month‐old plants with water (W), a selected grass medium (G3), G plus P. ehimensisKWN38 inoculation (G3P) or synthetic fungicide (F). The shoot dry weight in G3P was higher than that in W and F treatments at 15 days after zoospore infection (DZI). The root dry weight in G3P was also higher than that in W. The root mortality of G3 and W increased over 58 and 80% at 15 DZI, and some plants in those treatments wilted due to the failure of root physiology. The plants in G3P and F survived well because of their better root health conditions. Soil cellulase activity of G3P was consistently higher than that of W and F at earlier observation times (0, 2 and 6 DZI). The root β‐1,3‐glucanase activity of G3P promptly increased to maximum shortly after zoospore infection and reached the maximum value of 51.12 unit g?1 of fresh weight at 2 DZI. All these results indicate that inoculation of P. ehimensisKWN38 to the root zone of potted pepper plants increases plant growth, root and soil enzyme activities and alleviates the root death caused by infection with P. capsici zoospores. 相似文献
123.
Trabulus S Guven GS Altiparmak MR Batar B Tun O Yalin AS Tunckale A Guven M 《Molecular biology reports》2012,39(6):6995-7001
Patients with end-stage renal disease (ESRD) display enhanced genomic damage. DNA repair gene polymorphisms may affect DNA
repair capacity and modulate susceptibility to ESRD. In this study, we aimed to determine the frequency of polymorphisms in
two DNA repair enzyme genes, Xeroderma pigmentosum complementation group D (XPD) and X-ray cross-complementing group 1 (XRCC1),
in patients with ESRD and to evaluate their association with ESRD development. By using polymerase chain reaction (PCR) and
restriction fragment length polymorphism (RFLP), we genotyped four single nucleotide polymorphisms (SNPs) in XPD codons 312 and 751 and XRCC1 codons 194 and 399 in 136 dialysis patients (71 patients undergoing hemodialysis and 65 subjected to peritoneal dialysis)
and 147 healthy controls. Patients having XRCC1 399 Arg/Gln (OR:1.98; 95% CI: 1.21–3.25, P = 0.007) or XRCC1-399 Gln/Gln (OR: 3.95; 95% CI: 1.45–10.76, P = 0.005) genotype had a significantly higher risk of ESRD than those with XRCC1 399 Arg/Arg genotype. We also found a significantly higher frequency of the XRCC1 399Gln allele in patients with ESRD than in controls, with OR = 2.03 (95% CI = 1.08–3.81, P = 0.03). We further investigated the potential combined effect of these DNA repair variants on the risk of ESRD development.
It was found that combination of the Arg/Gln or Gln/Gln genotypes of XRCC1 Arg399Gln polymorphism with the two possible genotypes of XPD-Asp312Asn or with the Lys/Gln or Gln/Gln genotypes of XPD Lys751Gln was significantly associated with the development of ESRD. This is the first report showing an association between DNA repair
gene polymorphisms and ESRD development, and suggests that XRCC1 Arg399Gln polymorphism may confer increased risk for the development of the disease. Further larger studies should be conducted to
confirm these results. 相似文献
124.
Dervis ?zcelik Mustafa Naz?roglu Matem Tun?demir ?mer ?elik Melek ?ztürk M. F. Flores-Arce 《Biological trace element research》2012,150(1-3):342-349
Zinc is an element that under physiological conditions preferentially binds to and is a potent inducer of metallothionein under physiological conditions. The present study was conducted to explore whether zinc supplementation morphologically and biochemically protects against diabetic nephropathy through modulation of kidney metallothionein induction and oxidative stress in streptozotocin-induced diabetic rats. Thirty-two Wistar albino male rats were equally divided into four groups. The first group was used as untreated controls and the second group was supplemented with 30?mg/kg/day zinc as zinc sulfate. The third group was treated with streptozotocin to induce diabetes and the fourth group was treated with streptozotocin and supplemented with zinc as described for group 2. The blood glucose and micro-albuminuria levels, body and kidney weights were measured during the 42-day experimental period. At the end of the experiment, the kidneys were removed from all animals from the four groups. Diabetes resulted in degenerative kidney morphological changes. The metallothionein immunoreactivity level was lower and the kidney lipid peroxidation levels were higher in the diabetes group than in the controls. The metallothionein immunoreactivity levels were higher in the tubules of the zinc-supplemented diabetic rats as compared to the non-supplemented diabetic group. The zinc and metallothionein concentrations in kidney tissue were higher in the supplemented diabetic group compared to the non-supplemented diabetes group. The activity of glutathione peroxidase did not change in any of the four groups. In conclusion, the present study shows that zinc has a protective effect against diabetic damage of kidney tissue through stimulation of metallothionein synthesis and regulation of the oxidative stress. 相似文献
125.
Vu DM Yokoyama TA Sawada K Inagaki M Kanai G Lu J Kakuta T Adler S Nangaku M Saito A 《Biotechnology and bioengineering》2008,101(3):634-641
For the development of an antithrombogenic bioartificial hemofilter, in which the inner surface of hollow fibers is lined by endothelial cells, it is essential to increase the permeability of the cells in order to achieve a sufficient ultrafiltrate. We tried to increase it by using an actin microfilament polymerization inhibitor, cytochalasin B (CyB). Fifty microg/mL CyB was added for 2 h to the culture medium of confluent rat glomerular endothelial cells (RGEC) and human umbilical vein endothelial cells (HUVEC). Under the 130 mmHg hydrostatic pressure, the CyB-treated group produced significantly more ultrafiltration than the non-treated control group and this increase was maintained for at least 7 days. Horseradish peroxidase (HRP) permeability acutely and reversibly increased in the CyB-treated group compared with the non-treated control group. Scanning electron microscopy revealed a larger average diameter and increased number of fenestrae on the CyB-treated endothelial cells, compared with the non-treated cells. This phenomenon also lasted for at least 7 days. The platelet adherence test showed that CyB did not deteriorate the antithrombogenic property of endothelial cells. These results indicate that CyB is potentially applicable for the enhancement of endothelial cell permeability in an antithrombogenic bioartificial hemofilter. 相似文献
126.
Tun KL Itoh N Shimizu Y Yamanoi H Yoshinaga T Ogawa K 《International journal for parasitology》2008,38(2):211-217
Marteilioides chungmuensis is an ovarian parasite that causes nodule-like structures to appear on the gonads of female Pacific oysters, Crassostrea gigas. It is known that the prevalence of infection increases in summer and decreases from autumn to spring. To investigate the decrease in prevalence of infection and pathogenicity of the parasite, a biopsy method was developed to detect infected oysters, which were then monitored to calculate the mortality rate. Mortality of infected oysters was recorded monthly and changes in reproductive development observed histologically. Compared with control groups, a significant difference in mortality was observed in infected oysters in September and October. Histological observations showed that infected oysters produced oocytes continuously, even in autumn when healthy oysters were reproductively inactive. This prolonged spawning activity of infected oysters resulted in nutritional wasting and mortality. From December onwards, however, almost all infected oysters survived, though the infection persisted. Infection intensity decreased gradually from December. Histological observations revealed that, in winter, infected oysters released infected and uninfected oocytes through the genital canal. The gonad subsequently degenerated and was replaced with connective tissue, as in normal, healthy spent oysters. The results revealed that prevalence of infection decreased from September to May. It is hypothesised that the decline in prevalence within the epizootic area in autumn occurred because infected oysters died and that the winter decrease was due to recovery from infection. 相似文献
127.
Min Thura Joel
Xuan
En Sng Koon
Hwee Ang Jie Li Abhishek Gupta Jimmy
Ming Hong Cheng
William Hong Qi Zeng 《Bioscience reports》2021,41(9)
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the global pandemic of the Coronavirus disease in late 2019 (COVID-19). Vaccine development efforts have predominantly been aimed at ''Extra-viral'' Spike (S) protein as vaccine vehicles, but there are concerns regarding ‘viral immune escape’ since multiple mutations may enable the mutated virus strains to escape from immunity against S protein. The ‘Intra-viral’ Nucleocapsid (N-protein) is relatively conserved among mutant strains of coronaviruses during spread and evolution. Herein, we demonstrate novel vaccine candidates against SARS-CoV-2 by using the whole conserved N-protein or its fragment/peptides. Using ELISA assay, we showed that high titers of specific anti-N antibodies (IgG, IgG1, IgG2a, IgM) were maintained for a reasonably long duration (> 5 months), suggesting that N-protein is an excellent immunogen to stimulate host immune system and robust B-cell activation. We synthesized three peptides located at the conserved regions of N-protein among CoVs. One peptide showed as a good immunogen for vaccination as well. Cytokine arrays on post-vaccination mouse sera showed progressive up-regulation of various cytokines such as IFN-γ and CCL5, suggesting that TH1 associated responses are also stimulated. Furthermore, vaccinated mice exhibited an elevated memory T cells population. Here, we propose an unconventional vaccine strategy targeting the conserved N-protein as an alternative vaccine target for coronaviruses. Moreover, we generated a mouse monoclonal antibody specifically against an epitope shared between SARS-CoV and SARS-CoV-2, and we are currently developing the First-in-Class humanized anti-N-protein antibody to potentially treat patients infected by various CoVs in the future. 相似文献
128.
129.
The effects of ACE inhibitor and angiotensin receptor blocker on clusterin and apoptosis in the kidney tissue of streptozotocin-diabetic rats 总被引:1,自引:0,他引:1
Our first aim was to determine the effects of secreted clusterin (sCLU) and nuclear clusterin (nCLU) in diabetic nephropathy.
We also aimed to investigate the post-effects of angiotensin II blockage treatment on clusterin expression and to compare
these with apoptosis. Five groups of Wistar albino rats were used: First group consisted of healthy controls; the second group
included the untreated STZ-diabetics; 30 days of irbesartan or perindopril treated STZ-diabetics formed the third and the
fourth groups, respectively; while the subjects receiving a combined treatment with irbesartan and perindopril for 30 days
consisted the fifth group. TUNEL method for apoptosis and immunohistochemical staining for TGF-β1, α-SMA, clusterin-β and
clusterin-α/β antibodies were performed. Apoptotic cells especially increased in the kidney tubuli of untreated diabetic group
and on the contrary, a significant decrease was observed in the group that received a combined drug treatment. While sCLU
was increased in the glomeruli and tubuli of the untreated diabetic group, it was decreased in all the treated groups. An
increase in the nCLU immunoreactivity was observed in the podocytes, mesangial cells, and the injured tubule cells of the
untreated diabetic group. nCLU immunopositive cells were decreased in all treated diabetic groups. In addition to this, the
distribution of nCLU was similar to the distribution of apoptotic cells in the diabetic groups. Our results indicate that
sCLU expression in diabetic nephropathy was induced due to renal tissue damage, and the nCLU expression increase in renal
tubuli was related to apoptosis. Although irbesartan and perindopril prevented further renal injury in diabetes, a combined
application of low-dose ACEI and AT1R blockers revealed more efficient measures, by means of renal damage prevention. 相似文献
130.
Margarita V. Rodionova Sergei K. Zharmukhamedov Mehmet Sayım Karacan Kubra Begum Venedik Alexandr V. Shitov Turgay Tunç Serhat Mamaş Vladimir D. Kreslavski Nurcan Karacan Vyacheslav V. Klimov Suleyman I. Allakhverdiev 《Photosynthesis research》2017,133(1-3):139-153
Increasing inefficiency of production of important agricultural plants raises one of the biggest problems in the modern world. Herbicide application is still the best method of weed management. Traditional herbicides blocking only one of the plant metabolic pathways is ineffective due to the rapid growth of herbicide-resistant weeds. The synthesis of novel compounds effectively suppressing several metabolic processes, and therefore achieving the synergism effect would serve as the alternative approach to weed problem. For this reason, recently, we synthesized a series of nine novel Cu(II) complexes and four ligands, characterized them with different analyses techniques, and carried out their primary evaluation as inhibitors of photosynthetic electron transfer in spinach thylakoids (design, synthesis, and evaluation of a series of Cu(II) based metal–organic complexes as possible inhibitors of photosynthesis, J Photochem Photobiol B, submitted). Here, we evaluated in vitro inhibitory potency of these agents against: photochemistry and carbonic anhydrase activity of photosystem II (PSII); α-carbonic anhydrase from bovine erythrocytes; as well as glutathione reductase from chloroplast and baker’s yeast. Our results show that all Cu(II) complexes excellently inhibit glutathione reductase and PSII carbonic anhydrase activity. Some of them also decently inhibit PSII photosynthetic activity. 相似文献