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81.
Baysal E Bayazit YA Ceylaner S Alatas N Donmez B Ceylaner G San I Korkmaz B Yilmaz A Menevse A Altunyay S Gunduz B Goksu N Arslan A Ekmekci A 《Journal of genetics》2008,87(1):53-57
This study aimed to assess mutations in GJB2 gene (connexin 26), as well as A1555G mitochondrial mutation in both the patients with profound genetic nonsyndromic hearing loss and healthy controls. Ninety-five patients with profound hearing loss (>90 dB) and 67 healthy controls were included. All patients had genetic nonsyndromic hearing loss. Molecular analyses were performed for connexin 26 (35delG, M34T, L90P, R184P, delE120, 167delT, 235delC and IVS1+1 A-->G) mutations, and for mitochondrial A1555G mutation. Twenty-two connexin 26 mutations were found in 14.7% of the patients, which were 35delG, R184P, del120E and IVS1+1 A-->G. Mitochondrial A1555G mutation was not encountered. The most common GJB2 gene mutation was 35delG, which was followed by del120E, IVS1+1 A-->G and R184P, and 14.3% of the patients segregated with DFNB1. In consanguineous marriages, the most common mutation was 35delG. The carrier frequency for 35delG mutation was 1.4% in the controls. 35delG and del120E populations, seems the most common connexin 26 mutations that cause genetic nonsyndromic hearing loss in this country. Nonsyndromic hearing loss mostly shows DFNB1 form of segregation. 相似文献
82.
Variation in phosphorus efficiency among 73 bread and durum wheat genotypes grown in a phosphorus-deficient calcareous soil 总被引:3,自引:0,他引:3
A greenhouse experiment was carried out to study the severity of phosphorus (P) deficiency symptoms on leaves, shoot dry matter
production, and shoot concentration and content (the total amount per shoot) of P in 39 bread wheat (Triticum aestivum L.) and 34 durum wheat (Triticum durum L.) genotypes grown in a severely P-deficient calcareous soil with low (20mgPkg−1 soil) and adequate (80mgPkg−1 soil) P supply for 39 days. As the seed P concentration or content can affect plant performance under P-deficient conditions,
the seeds of the genotypes used in the present study were also analyzed for P concentration. Phosphorus efficiency (relative
shoot growth) of genotypes, calculated by the ratio of shoot dry matter production under low P to that under adequate P supply,
significantly differed among the genotypes, and varied between 46.7% and 78.6%. Phosphorus efficiency ranged from 51% to 71%
with an average of 61% for bread and from 47% to 79% with an average of 66% for durum wheat genotypes. There was no correlation
between P efficiency ratio and P concentration of plants (R
2=0.0001), but P efficiency of all bread and durum wheat genotypes showed a very significant correlation with the P content
(the total amount of P per shoot) (R
2=0.333***). The relationship between the P efficiency and total amount of P per shoot was much more significant in bread (R
2=0.341***) than in durum wheat (R
2=0.135*). Like shoot P concentrations, also severity of visible leaf symptoms of P deficiency on older leaves, including leaf chlorosis
and necrosis, did not correlate with P efficiency. In most cases, genotypes showing higher P efficiency had higher absolute
shoot dry weight under P deficient conditions. Under P deficient conditions, the absolute shoot dry weight very significantly
correlated with shoot P content (R
2=0.665***), but the correlation between the absolute shoot dry weight and shoot P concentration tended to be negative. There was also
variation in native seed P reserve of the genotypes, but this variation had no influence on the P efficiency. The results
indicate that the total amount of P per shoot and shoot dry matter production at low P supply are most reliable parameters
in ranking genotypes for P efficiency at early growth stage. In wheat germplasm tested in the present study, several wheat
genotypes are available showing both very high P efficiency and very high shoot content and concentration of P suggesting
that P acquisition ability should be most important mechanism for high P efficiency in such genotypes. On the other hand,
there are also genotypes in the germplasm having more or less same P concentration or P content in shoot but differing substantially
in P efficiency, indicating importance of P utilization at cellular level in P efficiency. All these results suggest that
P efficiency mechanisms can be different from one genotype to other within a given plant species. 相似文献
83.
84.
Removal of chromate anions from aqueous stream by a cationic surfactant-modified yeast 总被引:4,自引:0,他引:4
Bingol A Ucun H Bayhan YK Karagunduz A Cakici A Keskinler B 《Bioresource technology》2004,94(3):245-249
The removal of chromate anions (CrO(4)(2-)) from aqueous solution by a cationic surfactant-modified yeast was studied in a batch system. Cetyl trimethyl ammonium bromide (CTAB) was used for biomass modification; it substantially improved the biosorption efficiency. The influences of solution pH, CrO(4)(2-) anion concentrations and biomass concentration on the biosorption efficiency were investigated. The biosorption of chromate anions by modified yeast was strongly affected by pH. The optimum pH for biosorption of CrO(4)(2-) by modified yeast was 4.5-5.5. Zeta potential values of modified and unmodified yeast were determined at various pH values. Concentrations ranging from 5.2 to 208 mg/l Cr(VI) were tested and the biosorptive removal efficiency of the metal ions from aqueous solution was more than 99.5%. Freundlich and Langmuir isotherms were used to evaluate the data and the regression constants were determined. 相似文献
85.
Cytokines had important role in the pathogenesis of necrotizing enterocolitis (NEC). The aim of this study is to investigate if IFN-alpha has a prophylaxic effect on experimental NEC development in newborn rat pups. Twenty eight Wistar Albino newborn rat pups were divided into three groups. Control group rats were breast-fed, NEC group and interferon (IFN) group rat pups were hand-fed with premature newborn formula. IFN-alpha was administered subcutaneously at a dose of 50,000 IU/rat/day in IFN group. NEC was induced experimentally by cold stress twice a day in IFN and NEC groups. On the fourth day, the rats were killed, and all the intestine were removed to determine the tissue level of malonaldehyde (MDA) and histologic changes. The microscopic lesions in the NEC group rats were virtually the same as those seen in neonatal NEC, with severe separation of submucosa and/or lamina propria, loss of villi and in some cases necrosis to extention the muscularis. In contrast, in the rats treated with IFN, lesions were moderate separation of submucosa and/or lamina propria, edema in submucosal and muscular layers. Intestinal injury score and MDA levels in NEC group were significantly higher than in the IFN group (P<0.05). In conclusion it was suggested that IFN-alpha was effective in reducing the severity of NEC in rat pups. 相似文献
86.
Increased expression of angiogenic markers in patients with seasonal allergic rhinitis 总被引:3,自引:0,他引:3
Kirmaz C Ozbilgin K Yuksel H Bayrak P Unlu H Giray G Kiliccioglu B 《European cytokine network》2004,15(4):317-322
BACKGROUND: Increased vascularity due to neo-angiogenesis is an essential part of airway remodelling. Vascular endothelial growth factor (VEGF), CD34 and von Willebrand's factor (FvW) are known angiogenic markers. Angiogenesis and airway remodelling has been documented in asthma but not in allergic rhinitis. OBJECTIVE: We aimed to investigate the presence of increased angiogenesis and its relation to angiogenic molecules, namely VEGF, CD34 and FvW, in endothelial cells of nasal mucosa in patients with seasonal allergic rhinitis (SAR), using three different immunohistochemical analysis methods, namely HSCORE, microvessel density (MVD) and vascular surface density (VSD). The findings in allergic rhinitis were compared with the findings in nasal septal deviation (NSD), which is not associated with increased angiogenesis. METHODS: Twenty patients with symptomatic SAR, who were not under treatment, were enrolled in the study. Ten patients with NSD, who needed surgical therapy, served as the control group. Demographic characteristics did not differ between the two groups. Inferior turbinate biopsy was obtained from SAR patients and control patients, under local anaesthesia and during surgery respectively. All biopsies were evaluated for angiogenesis on the basis of VEGF, CD34 and FvW by two blinded histologists using three immunohistochemical analysis methods (HSCORE, MVD and VSD).Results. HSCORE, estimated on the basis of each staining technique, showed statistically significant differences among the two groups (p=0.002; p=0.045; p=0.016, respectively). Anti-CD34 and anti-VEGF showed higher MVD values in SAR when compared to the controls (p=0.038; p=0,009, respectively). No statistically significant difference was found in Anti-FvW-based MVD between SAR patients and controls (p=0.071). The measurements of VSD for FvW and VEGF from nasal biopsy specimens displayed a statistically significant difference between the two groups (p=0.004; p=0.0001, respectively). However, measurement of VSD for CD-34 was not significantly different between the groups (p=0.086). On the other hand, morphometric data obtained by all three methods did not correlated. CONCLUSION: There are a few studies that have investigated the essential role of angiogenesis in the pathogenesis of allergic rhinitis. We conclude that, increased angiogenesis may be as prominent in patients with allergic rhinitis as in patients with non-allergic nasal pathologies and may play an important role in the remodelling of nasal mucosa of subjects with SAR. 相似文献
87.
The effect of moderate hypothermia in acute ischemic stroke on pericyte migration: an ultrastructural study 总被引:2,自引:0,他引:2
Pericytes are essential components of the blood–brain barrier together with endothelial cells and astrocytes. Any disturbance of brain perfusion may result in blood–brain barrier dysfunction due to pericyte migration from the microvascular wall. The neuroprotective influence of hypothermia on ischemic brain injury has been clearly shown in models of both global and focal ischemia. Leakage of plasma proteins contributes to the extension of neuronal injury and hypothermia has a neuroprotective influence during the ischemic insult. This line of thinking impelled us to investigate the possible role of the pericytes in the occurrence of hypothermic protection during cerebral ischemia.In this study, we examined at the ultrastructural level the effect of moderate hypothermia on microvascular pericyte responses using a rat model of permanent middle cerebral artery occlusion. Twenty rats were divided into four groups. Middle cerebral artery occlusion was performed in all rats except the control group (first group), which was used to determine the pericyte morphology under normal conditions. In the second group, pericyte response to irreversible ischemia under normothermic conditions was examined at the end of the first hour. In the third group, pericyte response to hypoxia was examined under normothermic conditions three hours after ischemia. In the fourth group, temporalis muscle temperature was maintained at 27–29 °C for 1 h after middle cerebral artery occlusion and pericyte response was then examined at the ultrastructural level. In ischemic normothermic conditions at the end of the first hour (Group 2), a separation was observed between pericytes and the basement membrane and this was interpreted as pericyte migration from the microvascular wall. In ischemic normothermic conditions at the end of the third hour (Group 3), basement membrane disorganization and increased space between the basement membranes were seen in addition to the differentiation of second group. In ischemic hypothermic conditions at the end of the first hour (Group 4), pericyte separation or migration from basement membrane were not seen and the blood–brain barrier remained firm. These findings were interpreted by the authors as a possible relationship between pericyte behavior and neural protection during hypothermia. We suggest that hypothermia may delay the pericyte response but not necessarily attenuate it, and should be associated with hypothermic protection. 相似文献
88.
Juan YS Onal B Broadaway S Cosgrove J Leggett RE Whitbeck C De E Sokol R Levin RM 《Molecular and cellular biochemistry》2007,301(1-2):227-233
Objectives The influence of testosterone on the prostate and corpus cavernosum have been studied extensively. However, the influence
of testosterone on the lower urinary tract (bladder and urethra) have not been investigated to any great extent. The aim of
this study was to determine whether androgen deprivation alters lower urinary tract metabolism.
Methods A total of 16 rabbits were divided into four groups of four rabbits each. Each rabbit in groups 1–3 underwent surgical bilateral
castration for duration of 1, 2 , and 4 weeks, and group 4 underwent sham operations. Sections of bladder body and base wall
and mucosa, urethra and corpora were isolated, frozen, and stored under liquid nitrogen. The activities of citrate synthase-thapsigargin
sensitive Ca2+ ATPase (Sarco/Endoplasmic Reticulum Ca2+ ATPase [SERCA]), and choline acetyl-transferase were examined as markers for mitochondrial function, sarcoplasmic reticular
calcium storage and release, and cholinergic nerve function, respectively.
Results The activity of SR function indicator, Ca2+ ATPase was significantly higher in the control corpora than in the control bladder or urethra. Castration resulted in decreased
activity in the mitochondria specific enzyme, citrate synthase, the activity of which was greatest in the urethra and lowest
in the corpora. Cholinergic nerve density indicator, choline acetyl-transferase activity was greatest in the bladder body
and lowest in the urethra.
Conclusions Our data indicate that (1) significant differences exist in the activities of all three enzymes in the various organs associated
with the lower urinary tract; and (2) that castration results in significant alterations in the activities of all three enzymes
in the bladder body, base, urethra, and corpora. 相似文献
89.
90.
In this study, dieosin glutathione disulfide (Di-E-GSSG) was synthesized by the reaction of eosin isothiocyanate with GSSG. Di-E-GSSG had low fluorescence which increased approximately 70-fold on reduction of its disulfide bond. The substrate was used to monitor the disulfide reductase activity of PDI. Di-E-GSSG is the most sensitive pseudo substrate for PDI reductase activity reported to date. This probe was further used as an analytical reagent to develop an end point assay for measuring the redox state of PDI. The reduction of Di-E-GSSG by reduced enzyme was studied in the absence of reducing agents and the redox state of PDI was monitored as a function of the stoichiometric changes in the amount of eosin-glutathione (EGSH) generated by the active-site dithiols of PDI. The redox state of PDI was also studied under variable [GSH]/[GSSG] ratios. The results indicate that PDI is in approximately 1/2-reduced state where the [GSH]/[GSSG] ratio is between 1:1 and 3:1, conditions similar to the lumen of endoplasmic reticulum or in the extracellular environment. On the other hand, [GSH]/[GSSG] ratios of > or =8:1, such as in cytosol, all active-site thiols would be reduced. The study was extended to utilize Di-E-GSSG to investigate the effect of variable redox ratios on the platelet surface PDI reductase activity. 相似文献