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51.
Rana Al‐Awadhi Ph.D. Wassim Chehadeh Ph.D. Mohammad Jaragh BMBCH FRCPC Azza Al‐Shaheen B.Sc. Prem Sharma Ph.D. Kusum Kapila M.D. 《Diagnostic cytopathology》2013,41(2):107-114
This study investigates the distribution of human papillomavirus (HPV) in women with abnormal cervical cytology in Kuwait. Two hundred and ninety‐eight (298) abnormal ThinPreps were taken from women seeking routine gynecological care and screened for HPV DNA by real‐time PCR. HPV genotyping was determined by PCR‐based sequencing. HPV DNA was detected in 152 women (51%), and 29 different HPV genotypes were detected, comprising 16 high‐risk (HR) (16, 18, 31, 33, 35, 39, 45, 51, 53, 56, 58, 59, 66, 68, 73, 97), nine low‐risk (LR) (6, 11, 54, 61, 74, 81, 90, 102, 106), and four intermediate‐risk (IR) (62, 67, 84, 87). HPV16 had the highest prevalence (24.3%), followed by HPV11 (13.8%), HPV66 (11.2%), HPV33 (9.9%), HPV53 (9.2%), HPV81 (9.2%), HPV56 (7.9%) and HPV18 (6.6%). HPV prevalence was 86, 67, and 89% in women with invasive cervical carcinoma (ICC), high‐grade squamous intraepithelial lesion (HSIL) and low‐grade squamous intraepithelial lesion (LSIL), respectively. As for age distribution, 69% of all HPVs were found in women aged 20–29 years, and the HPV incidence rate deceased with increasing age. The proportion of single infections decreased as the severity of the cytological diagnosis increased, while the proportion of multiple infections increased. This study is the first of its type in Kuwait and one of few in the Middle East. The findings are consistent with the hypothesis that HPV infection is the primary cause of cervical neoplasia. They support HPV vaccine research to prevent cervical cancer and efforts to develop HPV DNA diagnostic tests. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc. 相似文献
52.
Most people who abuse alcohol are cigarette smokers. Previously, we have shown that malondialdehyde, an inflammation product of lipid peroxidation, and acetaldehyde, a component of both ethanol metabolism and cigarette smoke, form protein adducts that stimulate protein kinase C (PKC) activation in bronchial epithelial cells. We have also shown that PKC can regulate bronchial epithelial cell wound repair. We hypothesize that bovine serum albumin adducted with malondialdehyde and acetaldehyde (BSA–MAA) decreases bronchial epithelial cell wound repair via binding to scavenger receptors on bronchial epithelial cells. To test this, confluent monolayers of bovine bronchial epithelial cells were grown in serum-free media prior to wounding the cells. Bronchial epithelial cell wound closure was inhibited in a dose-dependent manner (up to 60%) in the presence of BSA-MAA than in media treated cells (Laboratory of Human Carcinogenesis [LHC]-9-Roswell Park Memorial Institute [RPMI]). The specific scavenger receptor ligand, fucoidan, also stimulated PKC activation and decreased wound repair. Pretreatment with fucoidan blocked malondialdehyde–acetaldehyde binding to bronchial epithelial cells. When bronchial epithelial cells were preincubated with a PKC alpha inhibitor, Gö 6976, the inhibition of wound closure by fucoidan and BSA–MAA was blocked. Western blot demonstrated the presence of several scavenger receptors on bronchial epithelial cell membranes, including SRA, SRBI, SRBII, and CD36. Scavenger receptor–mediated activation of PKC alpha may function to reduce wound healing under conditions of alcohol and cigarette smoke exposure where malondialdehyde–acetaldehyde adducts may be present. 相似文献
53.
Immunological profile of amyotrophic lateral sclerosis patients and their cell-mediated immune responses to viral and CNS antigens 总被引:2,自引:0,他引:2 下载免费PDF全文
H. Bartfeld C. Dham H. Donnenfeld Lila Jashnani R. Carp R. Kascsak J. Vilcek M. Rapport S. Wallenstein 《Clinical and experimental immunology》1982,48(1):137-147
The `immunological profile' of amyotrophic lateral sclerosis (ALS) patients was established from standard tests for B- and T-cell function. This showed no significant difference from age and sex-matched other neurological (CNS) disease controls and normal subjects. Immune complex (IC) levels in ALS serum differed significantly from normal controls but not from CNS controls. There was no relation between the various indices of immune activity of IC levels and the clinical disability of the ALS patient or progression of the disease. Distribution of complement-fixing antibodies to poliovirus was similar in sera of ALS and control groups. The in vitro cell-mediated immune responses to poliovirus, however, were significantly greater in ALS patients than in CNS controls and were inversely related to the ALS disability score. Poliovirus has not been demonstrated in the CNS or extra-CNS tissues of ALS patients by conventional means but, if latent or defective poliovirus or related virus were present, this could account for sensitization and a possible autoimmune mechanism. ALS patients exhibited in vitro cellular immunity to ALS and normal CNS subfractions. These responses were not related to the ALS disability score or progression of the disease and probably represent epiphenomena. 相似文献
54.
Choudhary S Verma SK Raheja G Kaur P Joshi K Gill KD 《Basic & clinical pharmacology & toxicology》2006,98(5):447-455
The present investigation was carried out to assess the protective efficacy of nimodipine against dichlorvos-induced organophosphate induced delayed neurotoxicity (OPIDN). Single subcutaneous dose of dichlorvos (200 mg/kg body weight) led to a consistent increase in the activity of both microtubule associated protein kinases viz. Ca2+/Calmodulin-dependent and cAMP dependent protein kinases, at all post exposure intervals (day 7, 15 and 21) as compared to that of controls. Autoradiography followed by microdensitometric studies demonstrated enhanced phosphorylation of 55 kDa and 280 kDa proteins in dichlorvos-exposed animals. These two proteins were confirmed to be tubulin and microtubule associated protein-2 (MAP-2) by western blotting. The hyperphosphorylation of these two proteins was shown to interfere with the assembly of neuronal microtubules as shown by electron microscopic studies that may eventually lead to possible disruption of neuronal cytoarchtecture resulting in axonal degeneration. Administration of nimodipine along with dichlorvos brought about a significant reduction in the activities of both the kinases as well as the extent of microtubule associated protein phosphorylation. This indicates that nimodipine, a centrally acting calcium channel blocker, may contribute to the amelioration of dichlorvos induced neurotoxicity by attenuation of calcium mediated disruption of cytoskeletal proteins and hence, calcium channel blockers like nimodipine have great future as new therapeutic agents for OPIDN. 相似文献
55.
Role of elevated S-adenosylhomocysteine in rat hepatocyte apoptosis: protection by betaine 总被引:3,自引:0,他引:3
Kharbanda KK Rogers DD Mailliard ME Siford GL Barak AJ Beckenhauer HC Sorrell MF Tuma DJ 《Biochemical pharmacology》2005,70(12):1883-1890
Previous studies from our laboratory have shown that ethanol consumption results in an increase in hepatocellular S-adenosylhomocysteine levels. Because S-adenosylhomocysteine is a potent inhibitor of methylation reactions, we propose that increased intracellular S-adenosylhomocysteine levels could be a major contributor to ethanol-induced pathologies. To test this hypothesis, hepatocytes isolated from rat livers were grown on collagen-coated plates in Williams’ medium E containing 5% FCS and exposed to varying concentrations of adenosine in order to increase intracellular S-adenosylhomocysteine levels. We observed increases in caspase-3 activity following exposure to adenosine. This increase in caspase activity correlated with increases in intracellular S-adenosylhomocysteine levels and DNA hypoploidy. The adenosine-induced changes could be significantly attenuated by betaine administration. The mechanism of betaine action appeared to be via the methylation reaction catalyzed by betaine-homocysteine-methyltransferase. To conclude, our results indicate that the elevation of S-adenosylhomocysteine levels in the liver by ethanol is a major factor in altering methylation reactions and in increasing apoptosis in the liver. We conclude that ethanol-induced alteration in methionine metabolic pathways may play a crucial role in the pathologies associated with alcoholic liver injury and that betaine administration may have beneficial therapeutic effects. 相似文献
56.
57.
Bhartiya D Shaikh A Nagvenkar P Kasiviswanathan S Pethe P Pawani H Mohanty S Rao SG Zaveri K Hinduja I 《Stem cells and development》2012,21(1):1-6
Very small embryonic-like stem cells (VSELs) are possibly lost during cord blood banking and bone marrow (BM) processing for autologus stem cell therapy mainly because of their small size. The present study was conducted on human umbilical cord blood (UCB, n=6) and discarded red blood cells (RBC) fraction obtained after separation of mononuclear cells from human BM (n=6), to test this hypothesis. The results show that VSELs, which are pluripotent stem cells with maximum regenerative potential, settle along with the RBCs during Ficoll-Hypaque density separation. These cells are very small in size (3-5 μm), have high nucleo-cytoplasmic ratio, and express nuclear Oct-4, cell surface protein SSEA-4, and other pluripotent markers such as Nanog, Sox-2, Rex-1, and Tert as indicated by immunolocalization and quantitative polymerase chain reaction (Q-PCR) studies. Interestingly, a distinct population of slightly larger, round hematopoietic stem cells (HSCs) with cytoplasmic Oct-4 were detected in the "buffy" coat, which usually gets banked or used during autologus stem cell therapy. Immunohistochemical studies on the umbilical cord tissue (UCT) sections (n=3) showed the presence of nuclear Oct-4-positive VSELs and many fibroblast-like mesenchymal stem cells (MSCs) with cytoplasmic Oct-4. These VSELs with nuclear Oct-4, detected in UCB, UCT, and discarded RBC fraction obtained after BM processing, may persist throughout life, maintain tissue homeostasis, and undergo asymmetric cell division to self-renew as well as produce larger progenitor stem cells, viz. HSCs or MSCs, which follow differentiation trajectories depending on the somatic niche. Hence, it can be concluded that the true stem cells in adult body tissues are the VSELs, whereas the HSCs and MSCs are actually progenitor stem cells that arise by asymmetric cell division of VSELs. The results of the present study may help explain low efficacy reported during adult autologous stem cell trials, wherein unknowingly progenitor stem cells are injected rather than the pluripotent stem cells with maximum regenerative potential. 相似文献
58.
Post-ischemic inflammation is a coordinated process,which lasts from hours to days and involves recruitment of inflammatory cells from blood to the brain endothelial cells.Recently,the adhesion of leukocytes at endothelium,especially neutrophils,and its implication in post-stroke neuronal injury have been extensively explored and reported in both experimental and clinical settings(Jian et al.,2019).However its role in diabetic patients following stroke is still elusive.Some significant differences such as risk factors,stroke subtypes and clinical outcomes are different between diabetic and nondiabetic. 相似文献
59.
Humphrey JH Hargrove JW Malaba LC Iliff PJ Moulton LH Mutasa K Zvandasara P Nathoo KJ Mzengeza F Chidawanyika H Zijenah LS Ward BJ;ZVITAMBO Study Group 《AIDS (London, England)》2006,20(10):1437-1446
OBJECTIVE: To test whether post-partum vitamin A supplementation can reduce incident HIV among post-partum women and identify risk factors for HIV incidence. DESIGN: Randomized, placebo-controlled trial METHODS: Between November 1997 and January 2001, 14,110 women were randomly administered 400,000 IU vitamin A or placebo within 96 h post-partum. HIV incidence was monitored among 9562 HIV-negative women. RESULTS: Cumulative incidence was 3.4% [95% confidence interval (CI), 3.0-3.8] and 6.5% (95% CI, 5.7-7.4) over 12 and 24 months post-partum, respectively. Vitamin A supplementation had no impact on incidence [hazard ratio (HR), 1.08; 95% CI, 0.85-1.38]. However, among 398 women for whom baseline serum retinol was measured, those with levels indicative of deficiency (< 0.7 micromol/l, 9.2% of those measured) were 10.4 (95% CI, 3.0-36.3) times more likely to seroconvert than women with higher concentrations. Furthermore, among women with low serum retinol, vitamin A supplementation tended to be protective against incidence (HR, 0.29; 95% CI, 0.03-2.60; P = 0.26), although not significantly so, perhaps due to limited statistical power. Severe anaemia (haemoglobin < 70 g/l) was associated with a 2.7-fold (95%CI, 1.2-6.1) greater incidence. Younger women were at higher risk of HIV infection: incidence declined by 5.7% (2.8-8.6) with each additional year of age. CONCLUSION: Among post-partum women, a single large-dose vitamin A supplementation had no effect on incidence, although low serum retinol was a risk factor for seroconversion. Further investigation is required to determine whether vitamin A supplementation of vitamin-A-deficient women or treatment of anaemic women can reduce HIV incidence. 相似文献
60.
Galectin-3 is a 31kD beta-galactoside binding lectin, which is known to be expressed in various neoplasms including thyroid tumors. This study was conducted to study the role of galectin-3 in differentiating benign from malignant thyroid nodules onfine needle aspirates (FNAC). Galectin-3 immuocytochemistry was performed in 70 cases with adequate smears. The cytology diagnosis of these cases was: papillary carcinoma (25), follicular neoplasm (16), adenomatous goiter (20), hyperplastic nodule (5), medullary carcinoma (5) and anaplastic carcinoma (1). Galectin-3 positivity was seen in 80% of papillary carcinomas, 37.5% offollicular neoplasms and in 60% of benign nodules. The single case of anaplastic carcinoma was positive but all the cases of medullary carcinoma were negativefor galectin-3. Three of thefollicular neoplasms that were diagnosed on histology as carcinoma were positive on cytology and one case offollicular adenoma was also positive. Our study shows that galectin-3 is strongly expressed in smears of papillary carcinoma. However, since it is also expressed in a variety of benign lesions, its role as a pre-surgical markerfor differentiating benignfrom malignant thyroid nodules is limited. 相似文献