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11.
Fulminant hepatic failure induced oxidative stress in nonsynaptic mitochondria of cerebral cortex in rats 总被引:2,自引:0,他引:2
Fulminant hepatic failure (FHF) is a condition with sudden onset of necrosis of hepatocytes and degeneration of liver tissue without any established liver disease. FHF is associated with increased ammonia levels in blood and brain, which is supposed to be neurotoxic, ultimately leading to neuronal death. Evidences from previous studies suggest for mitochondrial dysfunctions under hyperammonemic conditions. In the present investigation, on thioacetamide-induced FHF rat models, studies were undertaken on cerebral nonsynaptic mitochondrial oxidative stress. The results of the present study reveal elevated lipid peroxidation along with reduced total thiol levels in the cerebral cortex mitochondria of experimental animals compared to saline treated control rats. In addition, the enzymatic activities of glutathione peroxidase and glutathione reductase were decreased, with an elevation in Mn-SOD activity. Overall, thioacetamide-induced FHF in rats enhanced the levels of lipid peroxidation coupled with impaired antioxidant defenses in the cerebral nonsynaptic mitochondria. 相似文献
12.
Chaturvedi V Chu MD S Carrol BS M Brenner BS JW Nickoloff BJ 《Archives of pathology & laboratory medicine》2002,126(4):420-424
OBJECTIVE: It has been suggested that keratinocyte (KC) stem cells reside at the epicenter of a clonal population of cells. To estimate the territory or surface area covered by a single stem-cell-derived KC population in human skin, clonal skin maps were created from 3 healthy adult women and from normal skin of a psoriatic patient. DESIGN: Two hundred fifty-eight punch biopsy samples of various sizes (ranging from 2 to 8 mm in diameter) were analyzed for clonality employing X chromosome inactivation patterns at the human androgen receptor gene (HUMARA) locus. DNA was isolated and clonality established by significant decrease of either maternal or paternal X chromosome band patterns following restriction enzyme digestion, polymerase chain reaction amplification, and gel electrophoresis. RESULTS: Fifty-three (41%) of 128 two-mm biopsies were clonal, whereas only 6 (14%) of 43 three-mm, 5 (14%) of 36 four-mm, and 3 (8%) of 35 five-mm biopsies revealed a clonal population of KCs. By contrast, in 5 different biopsies from a psoriatic patient, including 4- or 5-mm sizes, all but 1 were clonal; even an 8-mm biopsy contained a clonal population of KCs. Mantel-Haenszel chi(2) analysis revealed a P value of.001, reflecting a strong trend in probability for presence of a single clone of KCs as related to size of the biopsy sample. By sequentially analyzing 30 contiguous 2-mm biopsy samples within a given strip of skin, 10 clonal domain changes, as reflected in maternal versus paternal switches, were observed. CONCLUSIONS: These results provide direct evidence of a clonal population of KCs in normal and psoriatic lesion-free skin, and indicate that a clonal epidermal unit of KCs frequently can be detected in small biopsies (2 mm), but that in normal skin sampling, overlapping clones are apparently present in larger (ie, 4-5-mm) biopsies, producing nonclonal patterns. The clonal domain of progeny in normal skin has a rather limited territorial boundary (2 mm in diameter). However, in lesion-free skin from a psoriatic patient, there may be clonal expansion of KCs due to perturbation in epidermopoiesis and/or stem cell distribution. 相似文献
13.
Vijaya K. Vijayan 《Neuroscience》1979,4(1):121-137
The distribution of the cholinergic neutrotransmitter enzyme, acetylcholinesterase, in the hippocampus and the dentate gyrus of the adult and the developing mouse was examined using a histochemical procedure. The pattern of acetylcholinesterase staining in the hippocampal region of the adult mouse closely resembled that reported for the rat by other investigators. Enzyme activity was present predominantly in the neuropil, where it was concentrated in the supra- and the infrapyramidal zones of the hippocampus as well as in the supragranular region and the hilus of the dentate gyrus. In contrast to the adult pattern, during the first week of postnatal development acetyleholinesterase activity appeared to be largely intracellular. Strong staining was observed in the cytoplasm of scattered neurons throughout the neuropil laminae, particularly in the hilus of the dentate gyrus. During the succeeding weeks, the characteristic neuropil reaction developed in a slow and progressive manner. reaching the adult pattern by the end of the third postnatal week. Between the third and the fifth weeks, there was a substantial increase in the staining intensity of the enzyme. As a result of the increased neuropil reaction, acetylcholinesterase-positive cells became less conspicuous after the second postnatal week. The progressive acquisition of staining for acetylcholinesterase in the neuropil of the hippocampus and the dentate gyrus of the mouse during the early postnatal period compared well with the proposed model of development of septohippocampal connections in the rat.The histochemical distribution of choline acetyltransferase in the hippocampus and the dentate gyrus of the adult mouse was also examined. The reaction was largely intracellular, in the cytoplasm of the pyramidal and the granule cells. Neuropil staining was confined to the mossy fibers and their terminals. This distribution profile is in conflict with the localization of this enzyme in the hippocampal region established by other investigators on the basis of microdissection and assay. The significance of the results of choline acetyltransferase histochemistry in relation to methodological problems is discussed. 相似文献
14.
Vemulakonda Vijaya M. Sevick Carter Juarez-Colunga Elizabeth Chiang George Janzen Nicolette Saville Alison Adams Parker Beltran Gemma King Jordon Ewing Emily Kempe Allison 《International urology and nephrology》2021,53(8):1485-1495
International Urology and Nephrology - Studies based on administrative databases show that infant pyeloplasty is associated with minority race/ethnicity but lack clinical data that may influence... 相似文献
15.
Deletions in the ligand for CD40 in X-linked immunoglobulin deficiency with normal or elevated IgM (HIGMX-1) 总被引:10,自引:0,他引:10
Ramesh Narayanaswamy; Fuleihan Ramsay; Ramesh Vijaya; Lederman Seth; Yellin Michael J.; Sharma Sunita; Chess Leonard; Rosen Fred S. 《International immunology》1993,5(7):769-773
Patients with X-linked Ig deficiency with normal or elevatedIgM (HIGMX-1) fail to switch from IgM/IgD to other Ig isotypes.Interaction between the B cell antigen CD40 and the CD40 ligandexpressed on activated T cells is critical for T cell drivenisotype switching. We have reported that T lymphocytes fromthree unrelated male patients with HIGMX-1 failed to expressCD40 ligand on their surface, but the mRNA for CD40 ligand wasof an apparently normal size and level. Analysis of CD40 ligandcDNA from two of the patients revealed deletions that alterthe reading frame. Patient 1 displayed two mutations: a C Atransversion at nucleotide 590 and the deletion of an adjacentC nucleotide. The second patient had a 58 bp deletion from nucleotides289–346. Furthermore, neither patient expressed a proteinproduct detectable by the CD40L mAb, 5c8. 相似文献
16.
Vijaya K. Gothwal Thomas Wright Ecosse L. Lamoureux Konrad Pesudovs 《Acta ophthalmologica. Supplement》2010,88(7):797-803
Acta Ophthalmol. 2010: 88: 797–803
Abstract.
Purpose: The visual functioning index (VFI) was one of the first questionnaires developed using classical test theory to assess outcomes of cataract surgery. However, it was not Rasch‐validated. The objective of this study was to examine the psychometric properties of the VFI using Rasch analysis in patients with cataract. Methods: The 11‐item VFI was self‐administered to 243 patients (mean age 73.9 years) drawn from a cataract surgery waiting list. We examined the response category thresholds, item fit statistics, differential item functioning and unidimensionality for the VFI and its three subscales. Results: Category thresholds were ordered. The person separation and reliability were low, indicating the poor discriminatory ability of the VFI. No items misfit but there was suboptimal targeting of item difficulty to patient ability. On the whole the items in the VFI were too easy for the sample. Only one item showed moderate differential item functioning. Conclusion: The VFI does not meet the stringent requirements of the Rasch model. However adding more items to suit the more able patients with cataract as well as those awaiting second‐eye cataract surgery could optimize the VFI. 相似文献17.
Chun‐Liang Tung Da‐Tong Ju Bharath Kumar Velmurugan Bo Ban Tran D. Dung Dennis J.‐Y. Hsieh Vijaya P. Viswanadha Cecilia H. Day Yueh‐Min Lin Chih‐Yang Huang 《Environmental toxicology》2019,34(12):1320-1328
Carthamus tinctorius L. (Compositae) is used in Chinese medicine to treat heart disease and inflammation. In our previous study, we found that C. tinctorius L. inhibited lipopolysaccharides (LPS)‐induced tumor necrosis factor‐alpha (TNF‐α) activation, JNK expression, and apoptosis in H9c2 cardiomyoblast cells. The present study was performed to investigate the protective effect of C. tinctorius extract (CTF) on LPS‐challenged H9c2 myocardioblast cell and to explore the possible underlying mechanism. Cell viability assay showed that LPS treatment decreased the cell viability of H9c2 cell, whereas CTF treatment reversed LPS cytotoxicity in a dose‐dependent manner, especially in the LPS + CTF 25 (μg/mL) group. LPS treatment‐induced apoptosis was determined by transferase‐mediated dUTP nick end labeling assay, and by Western blot. LPS‐induced apoptotic bodies were decreased following CTF treatment. Expression of TNF‐α, FAS‐L, FAS, FADD, caspase‐8, BID, and t‐BID was significantly increased in LPS‐treated H9c2 cells. In contrast, it was significantly suppressed by the administration of CTF extract. In addition, CTF treatment activates antiapoptotic proteins, Bcl‐2 and p‐Bad, and downregulates Bax, cytochrome‐c, caspase‐9, caspase‐3, and apoptosis‐inducing factor expression. Furthermore, CTF exerted cytoprotective effects by activating insulin‐like growth factor‐I (IGF‐I) signaling pathway leading to downregulation of the apoptotic proteins involved in FAS death receptor pathway. In addition, AG1024 and IGF‐I receptor (IGF‐IR) inhibitor and siRNA silencing reverses the effect of CTF implying that CTF functions through the IGF‐IR pathway to inhibit LPS‐induced H9c2 apoptosis. These results suggest that treatment with CTF extract prevented the LPS‐induced apoptotic response through IGF‐I pathway. 相似文献
18.
Ocular biometry in occludable angles and angle closure glaucoma: a population based survey 总被引:5,自引:0,他引:5
George R Paul PG Baskaran M Ramesh SV Raju P Arvind H McCarty C Vijaya L 《The British journal of ophthalmology》2003,87(4):399-402
Aim: To compare ocular biometric values in a population based sample of eyes with occludable angles, angle closure glaucoma, and normal subjects. METHOD: 2850 subjects from a population based glaucoma prevalence study underwent complete ocular examination including indentation gonioscopy. Ocular biometry was performed in all subjects classified to have occludable angles (n = 143); angle closure glaucoma (n = 22), and a random subgroup of 419 normal subjects. Ocular biometry readings between the groups were compared and statistically analysed using "t," "z," and Mann-Whitney U tests. RESULTS: The mean age among subjects with occludable angles (54.43 (SD 9.53) years) and angle closure glaucoma (57.45 (8.5) years) was significantly higher (p<0.001) than normal subjects (49.95 (9.95) years). Axial length was shorter (p<0.001) in the occludable angle group (22.07 (0.69) mm) compared to the normal group (22.76 (0.78) mm). Anterior chamber depth (ACD) was shallower (p<0.001) among subjects with occludable angles (2.53 (0.26) mm) than normal subjects (3.00 (0.30) mm). Lens thickness (LT) was greater (p<0.001) in people with occludable angles (4.40 (0.53) mm) compared to normal subjects (4.31 (0.31) mm). No significant difference was noted in axial length, ACD (p = 0.451), and LT (p = 0.302) between angle closure glaucoma and occludable eyes. CONCLUSION: South Indian eyes with angle closure glaucoma and occludable angles seem to have significantly shorter axial lengths, shallower anterior chambers and greater lens thickness compared to the normal group. 相似文献
19.
Carla M. M. Prado Isac S. F. Lima Vickie E. Baracos Robert R. Bies Linda J. McCargar Tony Reiman John R. Mackey Michelle Kuzma Vijaya L. Damaraju Michael B. Sawyer 《Cancer chemotherapy and pharmacology》2011,67(1):93-101
Purpose
Although body composition has emerged as an important predictor of drug efficacy and toxicity, explanations for this association are unclear. Our goal was to investigate relationships between lean body mass (LBM), liver size/function and epirubicin pharmacokinetics (PK) and toxicity.Methods
Data from a clinical study (n?=?24) of patients with breast cancer receiving adjuvant intravenous FE100C chemotherapy were used to examine relationships between LBM, liver size, and epirubicin clearance. Muscle tissue and liver mass were measured by analysis of computerized tomography cross-sectional images, and an extrapolation of muscle mass to total LBM compartment was employed. Population PK analysis of epirubicin was undertaken to test effects of body composition on epirubicin clearance and area under the curve (AUC).Results
Estimated LBM was extremely variable in this cohort ranging from 32.9 to 67.3?kg. LBM was associated with neutrophil nadir (r?=?0.5, P?=?0.023), and mean LBM was lower for patients presenting with toxicity compared to those where toxicity was absent (41.6 vs. 56.2?kg, P?=?0.002); 33% of variance in clearance was explained by LBM and aspartate aminotransferase (AST). Liver mass was not related to epirubicin clearance likely due to larger livers presenting with larger fat content, but liver attenuation (degree of fat infiltration) and AST were associated with AUC.Conclusion
To our knowledge, this is the first study to examine relationships between LBM, liver mass/function and epirubicin PK and toxicity. This exploratory work investigates the notion of organs and tissues having distinctive contributions to the distribution and metabolism of antineoplastic drugs. 相似文献20.
Brimacombe M Iffy L Apuzzio JJ Varadi V Nagy B Raju V Portuondo N 《Archives of gynecology and obstetrics》2008,277(5):415-422
On the basis of 333 documented cases of permanent perinatal neurological damage, associated with arrest of the shoulders at
birth, the authors conducted a retrospective study in order to evaluate the predisposing role, if any, of the utilization
of extraction instruments. The investigation revealed that 35% of all injuries occurred in neonates delivered by forceps,
ventouse or sequential ventouse–forceps procedures. This frequency was several-fold higher than the prevailing instrument
use in the practices of American obstetricians during the same years. A high rate of forceps and ventouse extractions was
demonstrable in all birth weight categories. Average weight and moderately large for gestational age fetuses underwent instrumental
extractions more often than grossly macrosomic ones. This circumstance indicates that forceps and ventouse are independent
risk factors, unrelated to fetal size. Their use entailed central nervous system injuries significantly more often than did
spontaneous deliveries. The findings suggest that extraction procedures may be as important as macrosomia among the factors
that lead to neurological damage in the child in connection with shoulder dystocia. Because they augment the intrinsic dangers
of excessive fetal size exponentially, the authors consider their use in case of ≥4,000 g estimated fetal weight inadvisable.
Sequential forceps–ventouse utilization further doubles the risks and is, therefore, to be avoided in all circumstances. 相似文献