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31.
Lipid peroxidation and scavenging enzyme levels in the liver of streptozotocin-induced diabetic rats
Bukan N Sancak B Yavuz O Koca C Tutkun F Ozçelikay AT Altan N 《Indian journal of biochemistry & biophysics》2003,40(6):447-450
In this study, alterations in the liver antioxidant enzymes status and lipid peroxidation in short-term (8-weeks) and long-term (24-weeks) diabetic rats were examined. Glutathione peroxidase (GSH-Px) activity and malondialdehyde (MDA) levels were significantly increased, but superoxide dismutase (SOD) activity was significantly reduced in 8-weeks diabetic rats, compared to control. Catalase (CAT) activity, however, was found unchanged. In 24-weeks diabetic rats, while GSH-Px activity was unchanged, but SOD and CAT activities and MDA levels were significantly increased, compared to control. These results suggest that diabetes-induced alterations in tissue antioxidant system may reflect a generalized increase in tissue oxidative stress. It can be concluded that lipid peroxidation and antioxidant enzyme levels are elevated in diabetic condition. Hence, diabetes mellitus, if left untreated, may increase degenerative processes due to accumulation of oxidative free radicals. 相似文献
32.
Sultana R Fuchs R Schmickler H Schlegel K Budzikiewicz H Siddiqui BS Geoffrey V Meyer JM 《Zeitschrift für Naturforschung. C, Journal of biosciences》2000,55(11-12):857-865
From Pseudomonas sp. CFML 95-275 a pyoverdin was isolated with a cyclopeptidic substructure. It could be shown that this pyoverdin is identical with one obtained from Pseudomonas fluorescens BTP 7 for which a lactone structure had been deduced from the interpretation of a FAB spectrum. The elucidation of the correct structure of the pyoverdin is described. 相似文献
33.
The toxic effect of vincristine on the apical cells of the rat caput epididymis was investigated. The drug was administered at 20 and 40 microg/kg body weight daily for 15 days. Light microscopy using semithin sections, and transmission electron microscopy, of the caput epididymis were undertaken. The results revealed that the basal region of the apical cell was in contact with the basement membrane and the luminal end took part in endocytosis. The apical cells reflected a dose-dependent response to vincristine (VCR) treatment. In general the changes included protrusion of the apical ends deep into the lumen, with the nucleus of the cell located in such protruded ends, and an increase in the abundance of lysosomal bodies and multivesicular bodies. These changes reflected the physiological response of the apical cell to VCR treatment rather than toxic manifestations. 相似文献
34.
To confirm when the levator aponeurosis is disinserted and how the disinsertion is compensated for in growing children, the earliest and latest photographs of the same children were the subjects of a retrospective comparative study regarding upward displacement of the superior palpebral crease and the eyeball in the palpebral fissure. Ninety-four children (48 boys and 46 girls) were selected from 615 patients with cleft lip and palate who were followed for more than several years at our outpatient clinic and whose 58,000 photographs were digitized. The earliest and latest photographs of the patients were taken in primary gaze position; the former, taken at less than 3 years of age, and the latter, taken at more than 6 years of age, were selected for this study. The intervals between the two photographs ranged from 3 to 14 years (mean, 9.61 years; SD, 3.11). The superior palpebral crease moved upward parallel with the growth of the children (p < 0.0001) as well as with the length of the growth period (p = 0.0141). The lower eyelid did not move downward (p < 0.0001). The eyeball also displaced upward parallel with growth (p < 0.0001) and with the length of the growth period (p = 0.0302). The more the superior palpebral crease was displaced upward, the more the eyeball was displaced upward (p = 0.0005). The levator aponeurosis may be likely to disinsert from the tarsus in growing children, thus requiring compensatory, excessive contraction of the levator muscle, which may cause upward displacement of the superior palpebral crease. Subsequently, excessive contraction of the superior rectus muscle in conjunction of the levator muscle may rotate the eyeball upward, which may incline the head. When the head is not inclined in the primary gaze position, compensatory contraction of the inferior rectus muscle to maintain the horizontal visual axis may displace the eyeball upward in the orbit by means of the inferior suspensory ligament of Lockwood. 相似文献
35.
36.
Ylenia Ingrasciotta Janet Sultana Francesco Giorgianni Andrea Fontana Antonio Santangelo Daniele Ugo Tari Domenico Santoro Vincenzo Arcoraci Margherita Perrotta Luisa Ibanez Gianluca Trifirò 《PloS one》2015,10(4)
Background
Non-steroidal anti-inflammatory agents (NSAIDs) are known to be associated with renal damage. No clear evidence exists regarding differential risk of chronic kidney disease (CKD), specifically, across various NSAIDs.Aim
The aim of this population-based case-control study was to evaluate the association between use of individual NSAIDs and risk of CKD in a general population of Southern Italy.Methods
A nested case-control study was carried out using the general practice Arianna database, identifying incident CKD patients as cases and matched controls from 2006 to 2011. The date of first CKD diagnosis was defined as the index date (ID). Conditional logistic regressions were performed to estimate the risk of CKD associated with NSAIDs by class and individual drugs as compared to non-use during different time windows (within one year, six or three months prior to ID), with the latter being defined as current users. Among current users, the effect of cumulative exposure to these drugs was evaluated.Results
Overall, 1,989 CKD cases and 7,906 matched controls were identified. A statistically significant increase in the risk of CKD was found for current users of oxicams (adjusted OR: 1.68; 95% CI: 1.15-2.44) and concerning individual compounds, for ketorolac (adj. OR: 2.54; 95% CI: 1.45-4.44), meloxicam (adj. OR: 1.98; 95% CI: 1.01-3.87) and piroxicam (adj. OR: 1.95; 95% CI: 1.19-3.21).Conclusions
The risk of CKD varies across individual NSAIDs. Increased risk has been found for ketorolac, which may precipitate subclinical CKD through acute renal damage, and long-term exposure to oxicams, especially meloxicam and piroxicam. 相似文献37.
Generation of a tamoxifen inducible Tnnt2MerCreMer knock‐in mouse model for cardiac studies 下载免费PDF全文
Jianyun Yan Nishat Sultana Lu Zhang David S. Park Akshay Shekhar Jun Hu Lei Bu Chen‐Leng Cai 《Genesis (New York, N.Y. : 2000)》2015,53(6):377-386
Tnnt2, encoding thin‐filament sarcomeric protein cardiac troponin T, plays critical roles in heart development and function in mammals. To develop an inducible genetic deletion strategy in myocardial cells, we generated a new Tnnt2:MerCreMer (Tnnt2MerCreMer/+) knock‐in mouse. Rosa26 reporter lines were used to examine the specificity and efficiency of the inducible Cre recombinase. We found that Cre was specifically and robustly expressed in the cardiomyocytes at embryonic and adult stages following tamoxifen induction. The knock‐in allele on Tnnt2 locus does not impact cardiac function. These results suggest that this new Tnnt2MerCreMer/+ mouse could be applied towards the temporal genetic deletion of genes of interests in cardiomyocytes with Cre‐LoxP technology. The Tnnt2MerCreMer/+ mouse model also provides a useful tool to trace myocardial lineage during development and repair after cardiac injury. genesis 53:377–386, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
38.
Ashini Bolia Brian W. Woodrum Angelo Cereda Melissa A. Ruben Xu Wang S. Banu Ozkan Giovanna Ghirlanda 《Biophysical journal》2014
Cyanovirin-N (CVN), a cyanobacterial lectin, exemplifies a class of antiviral agents that inhibit HIV by binding to the highly glycosylated envelope protein gp120. Here, we investigate the energetics of glycan recognition using a computationally inexpensive flexible docking approach, backbone perturbation docking (BP-Dock). We benchmarked our method using two mutants of CVN: P51G-m4-CVN, which binds dimannose with high affinity through domain B, and CVN(mutDB), in which binding to domain B has been abolished through mutation of five polar residues to small nonpolar side chains. We investigated the energetic contribution of these polar residues along with the additional position 53 by docking dimannose to single-point CVN mutant models. Analysis of the docking simulations indicated that the E41A/G and T57A mutations led to a significant decrease in binding energy scores due to rearrangements of the hydrogen-bond network that reverberated throughout the binding cavity. N42A decreased the binding score to a level comparable to that of CVN(mutDB) by affecting the integrity of the local protein structure. In contrast, N53S resulted in a high binding energy score, similar to P51G-m4-CVN. Experimental characterization of the five mutants by NMR spectroscopy confirmed the binding affinity pattern predicted by BP-Dock. Despite their mostly conserved fold and stability, E41A, E41G, and T57A displayed dissociation constants in the millimolar range. N53S showed a binding constant in the low micromolar range, similar to that observed for P51G-m4-CVN. No binding was observed for N42A. Our results show that BP-Dock is a useful tool for rapidly screening the relative binding affinity pattern of in silico-designed mutants compared with wild-type, supporting its use to design novel mutants with enhanced binding properties. 相似文献
39.
Kirthiram K. Sivakumar Jone A. Stanley Joe A. Arosh Melissa E. Pepling Robert C. Burghardt Sakhila K. Banu 《Developmental biology》2014
Hexavalent chromium (CrVI), one of the more toxic heavy metals, is widely used in more than 50 industries such as chrome plating, welding, wood processing and tanneries. As one of the world?s leading producers of chromium compounds, the U.S. is facing growing challenges in protecting human health against multiple adverse effects of CrVI. CrVI is rapidly converted to CrIII intracellularly, and can induce apoptosis through different mechanisms. Our previous studies demonstrated postnatal exposure to CrVI results in a delay or arrest in follicle development and puberty. Pregnant rats were treated with 25 ppm potassium dichromate (CrVI) from gestational day (GD) 9.5 to 14.5 through drinking water, placentae were removed on GD 20, and total Cr was estimated in the placentae; ovaries were removed from the F1 offspring on postnatal day (PND)-1 and various analyses were performed. Our results show that gestational exposure to CrVI resulted in (i) increased Cr concentration in the placenta, (ii) increased germ cell apoptosis by up-regulating p53/p27–Bax–caspase-3 proteins and by increasing p53–SOD-2 co-localization; (iii) accelerated germ cell cyst (GCC) breakdown; (iv) advanced primordial follicle assembly and primary follicle transition and (v) down regulation of p-AKT, p-ERK and XIAP. As a result of the above events, CrVI induced early reproductive senescence and decrease in litter size in F1 female progeny. 相似文献
40.
Emel Banu Buyukunal Bal Suleyman Bayar Mehmet Ali Bal 《Journal of microbiology (Seoul, Korea)》2010,48(3):267-274
The prevalence and antimicrobial susceptibilities of Staphylococci and Streptococci were assessed from subclinical mastitis
cases. One hundred Coagulase-Negative Staphylococci (CNS) and 34 Streptoccocci were identified. The most frequently isolated
species were Staphylococcus haemolyticus (27%) and Staphylococcus simulans (24%). Susceptible CNS species revealed the highest resistance to penicillin G (58%), ampicillin (48%), neomycin (20%), and
oleandomycin (14%). CNS methicillin resistance rates within 82 isolates were 21.95% and 1.22% by disk diffusion and PCR methods,
respectively. These results suggested the disk diffusion method was more prone to yield false positives. Partial sequencing
of the 16S rRNA region from the mecA carrying isolate (S. haemolyticus) was homologous with S. haemolyticus sequences/accessions obtained from GenBank. However, the mecA gene sequence from this isolate was more closely allied with the S. aureus mecA gene of human origins. Identical sequence data was acquired from the National Center for Biotechnology Information (NCBI)
database, suggesting horizontal gene transfer between the two species. CNS β-lactamase activity within 81 isolates was 29.63%.
The most frequently isolated Streptococcus species were S. uberis (52%) and S. agalactiae (15%). Oleandomycin was the least effective antimicrobial agent on these isolates with 59% susceptibility. Results indicated
that CNS and Streptococci exhibited various antimicrobial resistance responses. Consequently, isolation and identification
of udder pathogens in herds suffering from subclinical agents is essential to select the most effective antimicrobial agent.
Moreover, multiple resistance features of methicillin resistant (MR) isolates should be considered during antimicrobial susceptibility
tests. 相似文献