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51.
Dilek Gogas Yavuz Belgin Kü?ükkaya H. ?nder Ers?z A. Süha Yal?in Kaya Emerk Sema Akalin 《Experimental diabetes research》2002,3(2):145-151
Nonenzymatic glycation of tissue and plasma
proteins may stimulate the production of oxidant
and carbonyl stress in diabetes. The aim
of this study was to evaluate the effects of
aminoguanidine (AG) on lipid peroxidation,
protein oxidation and nitric oxide (NO) release
in diabetic rat kidneys. After induction of diabetes
with streptozotocin, female Wistar rats
were divided into 2 groups. Group DAG (n=9)
rats were given AG hydrogen carbonate (1 g/L)
in drinking water and group D (n=8) was diabetic
control rats given only tap water. Group
H (n=8) was followed as healthy controls. At
the end of an 8 week period, NO release, lipid
and protein oxidation were determined in kidney
tissues. NO release was significantly lower
in diabetic rats compared with healthy controls
(p<0.05). Lipid peroxidation was significantly
high in group D (3.9 ± 0.3 nmol MDA/g tissue)
compared with the group DAG (2.6 ± 0.1 nmol
MDA/g tissue, p<0.01) and group H (2.4 ± 0.2
nmol MDA/g tissue). Protein oxidation was
significantly higher in diabetics than healthy
controls (563.8 ± 23.9, 655.8 ± 7.2 , 431.5 ±
8.8 mmol carbonyl / g tissue for group DAG, D
and H, respectively, p< 0.05). A positive correlation
between albuminuria and thiobarbituric
acid reactive substance (TBARS) levels (r= 0.54,p<0.005) and carbonyl content (r=0.70,
p<0.0005) in kidney homogenate were
observed.
Although AG treatment had no effect on NO
release, it significantly decreased lipid peroxidation
in diabetic rat cortices. Consequently
increased lipid peroxidation -as well as- protein
oxidation could be involved in the pathogenesis
of diabetic albuminuria. 相似文献
52.
Federico Selvi 《Nordic Journal of Botany》2009,27(2):125-133
The new species Armeria saviana, endemic to an isolated mountain chain of the Tyrrhenian Antiappennine system in south Tuscany, central Italy, is described and illustrated. The plant is diploid with 2n=18. It can be distinguished from the related species A. denticulata (Bertol.) DC and A. canescens (Host) Ebel, mainly by leaf characters, capitula, bracts and flowers. The systematic position of the controversial taxon A. majellensis Boiss. subsp. ausonia F. Bianchini, to which the new species has formerly been assigned by some authors, is discussed. A lectotype for A. denticulata is designated. 相似文献
53.
We investigated the serum concentrations of zinc and copper during the inflammatory process together with the effect of treatment
with a nonsteroid anti-inflammatory agent on these trace elements concentrations. In the present study, we used 92 guinea
pigs, 12 of which constituted the control group; the remaining 80 were the experimental group. To start with, proquazone (as
anti-inflammatory agent) was administered orally to 40 guinea pigs of the experimental group at 20-mg/kg doses 2 h before
the surgery. Throughout the experimental period, the above dose was administered to the animals twice a day. We produced inflammation
in all animals of the experimental group by using carrageenan (inflammatory agent) dropped into mandibular surgical defects.
Serum concentrations of zinc and copper were determined by atomic absorption spectrophotometry in both groups at the 6th,
48th, 120th, 168th, and 240th h. The serum zinc concentrations of the carrageenan-administered group decreased significantly
(p<0.01). When comparing the serum zinc concentrations of the carrageenan plus proquazone-administered group with those of control
group, the decrease (p<0.05) at the 6th, 48th, and 120th h were statistically significant. When the copper serum concentrations of the carrageenan-administered
group were compared with those of the control group, at the 48th, 120th, and 168th h, a statistically significant increase
(p<0.01) was observed. However, there was no significant change in the carrageenan plus proquazone-administered group at the
168th and 240th h. As a result during the acute phase of inflammation, serum zinc concentrations decreased, whereas serum
copper concentrations increased. The alterations in zinc concentrations were more rapid than those in copper concentrations,
but the administration of proquazone slowed the rate of decrease in serum zinc concentrations.
This work was presented at the Fourth International Congress of Pathophysiology, June 29–July 5, 2002, Budapest, Hungary. 相似文献
54.
55.
Variability of HXT2 at the protein and gene level was investigated among Saccharomyces sensu stricto and other yeast species. Results showed that the HXT2 gene is probably present in yeast genera other than Saccharomyces, suggesting that this gene is widely distributed in the yeast world. Chromosomal analyses indicated the stable location of HXT2 on the same chromosome and with the same copy number throughout the entire sensu stricto group. Results of the immunoblotting assay demonstrated that all strains tested (with the exception of S. cerevisiae DBVPG 6042) exhibited a lower level of Hxt2p expression than that shown by laboratory wild-type. Moreover, Hxt2p expression seems to reinforce the taxonomical differences between the two pairs of species (S. cerevisiae and S. paradoxus vs. S. pastorianus and S. bayanus) within the sensu stricto group of the genus of Saccharomyces that also reflect their different ecological niche. 相似文献
56.
57.
The function of intestinal keratins is unknown, although keratin 8 (K8)-null mice develop colitis, hyperplasia, diarrhea, and mistarget jejunal apical markers. We quantified the diarrhea in K8-null stool and examined its physiologic basis. Isolated crypt-units from K8-null and wild-type mice have similar viability. K8-null distal colon has normal tight junction permeability and paracellular transport but shows decreased short circuit current and net Na absorption associated with net Cl secretion, blunted intracellular Cl/HCO3-dependent pH regulation, hyperproliferation and enlarged goblet cells, partial loss of the membrane-proximal markers H,K-ATPase-beta and F-actin, increased and redistributed basolateral anion exchanger AE1/2 protein, and redistributed Na-transporter ENaC-gamma. Diarrhea and protein mistargeting are observed 1-2 d after birth while hyperproliferation/inflammation occurs later. The AE1/2 changes and altered intracellular pH regulation likely account, at least in part, for the ion transport defects and hyperproliferation. Therefore, colonic keratins have a novel function in regulating electrolyte transport, likely by targeting ion transporters to their cellular compartments. 相似文献
58.
Sivasankaran TG Udayakumar R Elanchezhiyan C Sabhanayakam S 《Cell biology international》2008,32(2):293-297
The effects of sildenafil citrate with ethanol on the rat testis was studied using scanning electron microscopy. Male Albino rats were divided into 8 groups, each being treated for a maximum of 45 days as follows. In the 4 short-term treatment groups, control rats were administered normal saline orally, whereas experimental animals were fed sildenafil citrate (Viagra) 1 microg/g with 18% ethanol (5 g/kg body weight), which was given orally as a single dose. After 1, 2.5, 4 and 24h the rats were killed. In the 4 long-term treatment groups, daily continuous doses of drug and ethanol with a single dosage were given for 15, 30 and 45 days and the animals killed 4h after the last dosage. Changes in the testis were compared with the normal healthy rat testis. The use of a scanning electron microscope for evaluation of the changes in the testis is more suitable for observation of the surface and morphological shapes of the tissue structures. 相似文献
59.
Substituted polyaniline/chitosan (sPANI/Ch) composites were chemically synthesized in H2SO4 and CH3COOH synthesis media. Structural and physical properties of the composites were characterized by using FTIR, SEM, TGA, UV–vis, XRD techniques, and conductivity measurements. The effect of synthesis media on morphology, thermal stability, conductivity, and crystalline properties was investigated. Chemical interactions between substituted polyanilines and chitosan were explained using FTIR spectra results. The different morphological surfaces were observed in SEM images of the composites. The size of the substituted polyaniline/chitosan (sPANI/Ch) composites was in nanoscale, and the composites synthesized in acetic acid media showed smaller structures than those of H2SO4 media and pure chitosan. It was interpreted from XRD results that the composites have amorphous structure and the PNEANI/Ch–CH3COOH composite has the highest crystallinity. 相似文献
60.
A. Selvi Jaseetha Abdul Salam Nilanjana Das 《World journal of microbiology & biotechnology》2014,30(11):2839-2850
Cefdinir, a semi-synthetic third generation cephalosporin antibiotic being considered as an emerging pollutant, demands removal from aquatic ecosystems. A yeast strain isolated from pharmaceutical wastewater which was identified as Ustilago sp. SMN03 by molecular techniques and was found to be capable of utilizing cefdinir as a sole carbon source. The isolate was found to degrade 81 % of cefdinir within 6 days under optimized conditions viz. pH 6.0, temperature 30 °C, a shaking speed of 120 rpm, an inoculum dosage of 4 % (w/v) and an initial cefdinir concentration of 200 mg L?1. Kinetic studies revealed that cefdinir degradation followed the pseudo-first order model, a rate constant of 0.222 per day and a half-life period of 3.26 days. Using LC–MS analysis, six novel intermediates formed during the cefdinir degradation were identified and characterized. FT-IR analysis showed that the functional groups ranging from 1,766 to 1,519 cm?1, characteristic for lactam ring were completely removed during the cefdinir degradation. The opening of the β-lactam ring was one of the major steps in the cefdinir degradation process. Based on the results from the present study, a possible pathway of cefdinir degradation by Ustilago sp. SMN03 was proposed. To the best of our knowledge, this is the first report on microbial degradation of cefdinir by yeast. 相似文献