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31.
The clinical application of cisplatin (CP), one of the most extensively used antineoplastic drug, is restricted by its numerous side effects. CP's antitumor potential resides in the free generation of reactive oxygen species leading to oxidative stress. This stress is a source of the side effects associated with its use. Ellagic acid (EA), a polyphenol is known to possess multiple health benefits owing to its antioxidant properties. EA is largely metabolized by the colon microbiota of different mammals and therefore was a polyphenol of choice in the present study. The present study was thus carried out to explore the protective potential of EA on CP induced hepatotoxicity in colon tumor bearing mice. The administration of EA (10 mg/kg bwt po daily for 6 weeks) significantly ameliorated the toxicity caused by CP (5 mg/kg bwt ip once a week for 4 weeks). Activities of liver marker enzymes and lactate dehydrogenase were brought back to normal. EA cotreatment also led to a marked reduction in the extent of peroxidative damage to liver tissue as was evident from the improvement in the histopathological changes observed and FT‐IR analysis. The present study, therefore, suggests that the administration of EA reduces the CP‐induced hepatotoxicity, thereby emerging out as a potential candidate for chemopreventive action. 相似文献
32.
McMorran BJ Patat SA Carlin JB Grimwood K Jones A Armstrong DS Galati JC Cooper PJ Byrnes CA Francis PW Robertson CF Hume DA Borchers CH Wainwright CE Wainwright BJ 《Clinical chemistry》2007,53(10):1782-1791
BACKGROUND: Airway inflammation in cystic fibrosis (CF) is exaggerated and characterized by neutrophil-mediated tissue destruction, but its genesis and mechanisms remain poorly understood. To further define the pulmonary inflammatory response, we conducted a proteome-based screen of bronchoalveolar lavage fluid (BALF) collected from young children with and without CF experiencing endobronchial infection. METHODS: We collected BALF samples from 45 children younger than 5 years and grouped them according to the presence of respiratory pathogens: > or = 1 x 10(5) colony-forming units (CFU)/mL BALF (18 and 12 samples with and without CF, respectively) and <1 x 10(5) CFU/mL (23 and 15 samples). BALF proteins were analyzed with SELDI-TOF mass spectrometry (MS) and H4 ProteinChips. Proteins were identified and characterized using trypsin digestion, tandem MS, Fourier transform ion cyclotron resonance MS, immunoblotting, and ELISA. RESULTS: The SELDI-TOF MS BALF profiles contained 53 unique, reliably detected proteins. Peak intensities of 24 proteins differed significantly between the CF and non-CF samples. They included the neutrophil proteins, alpha-defensin 1 and 2, S100A8, S100A9, and S100A12, as well as novel forms of S100A8 and S100A12 with equivalent C-terminal deletions. Peak intensities of these neutrophil proteins and immunoreactive concentrations of selected examples were significantly higher in CF than non-CF samples. CONCLUSIONS: Small neutrophil-derived BALF proteins, including novel C-terminal truncated forms of S100A proteins, are easily detected with SELDI-TOF MS. Concentrations of these molecules are abnormally high in early CF lung disease. The data provide new insights into CF lung disease and identify novel proteins strongly associated with CF airway inflammation. 相似文献
33.
34.
We describe the risk factors for and the natural history and response to treatment of extramedullary (EM) relapse in 183 patients who underwent allogeneic bone marrow transplantation (alloBMT) for a variety of haematological malignancies at our institution over a 7 1/2 year period. Fifty-one patients relapsed; 15 had EM relapse either alone or in association with marrow involvement. A retrospective analysis found that the presence of chronic GVHD and a longer interval between transplant and relapse were independently associated with an increased risk of EM compared to marrow-only relapse. EM relapse was also associated with a longer post-relapse survival. Patients with EM relapse appeared to respond to cytotoxic therapy but not to DLI. EM relapse after alloBMT may be more common than previously thought and have a better prognosis than marrow-only relapse. While patients developing chronic GVHD after alloBMT have a lower overall relapse risk than those who do not, they may be more prone to delayed relapse at EM sites. 相似文献
35.
Yasmin Bhurgri Kauser Nazir Yasmeen Shaheen Ahmed Usman Naveen Faridi Hadi Bhurgri Jawaid Malik Imtiaz Bashir Asif Bhurgri Sheema H Hasan Naila Kayani Shm Zaidi 《Asian Pacific journal of cancer prevention》2007,8(4):489-494
Aim: To provide demographics and pathology of cancer of the uterine corpus in Karachi. Methodology: Data for 66 incident cases of cancer corpus uteri, ICD-10 category C54-5 registered at the Karachi Cancer Registry, for Karachi South, during a 3 year period, 1st January, 1995 to 31st December 1997 were reviewed. Results: Cancer uterine corpus (1995-97) was the sixth most common malignancy, following breast, oral cavity, ovary, esophagus and cervix. The age standardized incidence rate (ASR) world and crude incidence rate (CIR) per 100,000 were 6.4 (4.73 to 8.01) and 2.9 (2.18 to 3.57). The mean age was 53.7 years (SD 15.6; range 6-90 years). Fifty eight cases were endometrial carcinoma with ASR world and CIR per 100,000 of 5.77 (4.20 to 7.33) and 2.53 (1.88 to 3.18) respectively. Sarcomas comprised 6% of the cases. Approximately a third of the females (28.8%) were below 50 years of age. The age-specific curves showed a gradual increase from the fourth till the seventh decade, followed by an actual apparent decrease in risk after 70 years. Peak incidence was observed in the 65-69 year age group. Presenting symptoms were post-menopausal bleeding (86.4%) and purulent discharge (4%). Associated pathologies included adenomyosis, adenomatous hyperplasia (12% each) or leiomyoma (8%). Associated clinical conditions were diabetes mellitus and hypertension (4% each). The majority of the cases presented as well differentiated (39.4%), localized (59.1%) lesions. Conclusion: The incidence of cancer corpus uteri in Karachi South reflects a moderate risk population, predominantly middle aged with a higher socio-economic status. On the average the malignancy is observed a decade earlier then reported elsewhere. This calls for in-depth investigation of risk factors and identification of underlying etiology. 相似文献
36.
Jennifer Stone Lyle C Gurrin Graham B Byrnes Christopher J Schroen Susan A Treloar Emma J D Padilla Gillian S Dite Melissa C Southey Vanessa M Hayes John L Hopper 《Cancer epidemiology, biomarkers & prevention》2007,16(7):1479-1484
BACKGROUND: Mammographic density, the light/white radiographic appearance on a mammogram that represents connective and epithelial tissue, is a strong risk factor for breast cancer which seems to be highly heritable. Little is known about its genetic determinants. METHODS: We studied 457 women from 207 sisterhoods (104 monozygotic twins, 182 dizygotic twins, and 171 singletons). Percentage mammographic density (PMD) as well as dense area and nondense area were calculated using a computer-assisted method. We measured six single nucleotide polymorphisms from six candidate genes (COMT, HSD3B1, IGFBP3, HER2, XPD, and XRCC3). Associations between genotypes and mammographic measures were tested (a) cross-sectionally using a multivariate normal model fitted using FISHER that allowed separate correlations for monozygotic, dizygotic, and nontwin pairs and (b) within sister pairs using paired t tests. RESULTS: Cross-sectionally, each additional copy of the HSD3B1 Asn(367)Thr variant allele was associated with lower PMD (-3.47% per allele; SE = 1.65; P = 0.035). Within-pair regression estimates confirmed this association. There was no evidence for an association between the mammographic density measures and any of the other variants studied. CONCLUSION: We have replicated an association between a variant in the HSD3B1 gene and PMD, which suggests that HSD3B1 may be genetic determinant of mammographic density. 相似文献
37.
Prion diseases is another name for a group of 'transmissible spongiform encephalopathies'. Creutzfeldt-Jakob disease, the first prion disease described in humans, occurs in sporadic, familial or iatrogenic form. Other transmissible spongiform encephalopathies in humans such as familial Creutzfeldt-]akob disease, Gerstmann-Str?ussler-Scheinker disease and fatal familial Insomnia have been shown to be associated with specific prion protein gene mutations. In 1996, a new variant of Creutzfeldt-Jakob disease was reported in the United Kingdom among young patients with unusual clinical features and unique neuropathological findings. This new form could be due to transmission to humans of the agent causing bovine spongiform encephalopathy. While examination of brain tissue is the key to making a diagnosis, it is not always possible antemortem. Immunological tests such as ELISA or western blot assays along with tests for 1 4-3-3 protein in the cerebrospinal fluid remain the main tools of diagnosis. Conventional disinfection and sterilization practices are Ineffective for these agents. The unusual properties of prions pose a challenge for treatment, surveillance and control of these diseases. 相似文献
38.
Byrnes GB 《Statistics in medicine》2002,21(21):3249-3260
Sample size and power formulae are derived for designing trials of vaccine cost-effectiveness in healthy working adults. When existing trials of influenza vaccine have presented sample size calculations, these have been based on vaccine effectiveness. A Markov model is introduced to account for non-independence of working days lost. Two effect sizes need to be specified, one for a reduction in the number of episodes of absence and the second for a reduction in the mean duration of episodes. The relative cost of vaccine provision is also incorporated. Applying the resulting formulae to published studies indicates that most were underpowered to detect any financial benefit. Moreover, biased estimates of variance have led to led to incorrect inference. 相似文献
39.
Ahmad VU Yasmeen S Ali Z Khan MA Choudhary MI Akhtar F Miana GA Zahid M 《Journal of natural products》2000,63(7):1010-1011
A new guaianolide, taraxacin (1), and a known sesquiterpene ketolactone (2) have been isolated from an ethyl acetate-soluble part of a methanolic extract of Taraxacum wallichii. The structure of 1 was established using NMR, MS, and X-ray crystallographic methods. The (13)C NMR data of 2 is also being reported for the first time. 相似文献
40.
Colman K. Byrnes MB BCh ; Robert W. Malone MD ; Nabeel Akhter MD ; Petra H. Nass PhD ; Antoinette Wetterwald ; Marco G. Cecchini ; Mark D. Duncan MD ; John W. Harmon MD 《Wound repair and regeneration》2004,12(4):397-403
Transfection of wounds with DNA-encoding growth factors has the potential to improve healing, but current means of nonviral gene delivery are inefficient. Repeated high doses of DNA, necessary to achieve reliable gene expression, are detrimental to healing. We assessed the ability of in vivo electroporation to enhance gene expression. Full-thickness cutaneous excisional wounds were created on the dorsum of female mice. A luciferase- encoding plasmid driven by a CMV promoter was injected at the wound border. Following plasmid administration, electroporative pulses were applied to injection sites. Pulse parameters were varied over a range of voltage, duration, and number. Animals were euthanized at intervals after transfection and the luciferase activity measured. Application of electric pulses consistently increased luciferase expression. The electroporative effect was most marked at a plasmid dose of 50 micro g, where an approximate tenfold increase was seen. Six 100- micro s-duration pulses of 1750 V/cm were found to be the most effective in increasing luciferase activity. High numbers of pulses tended to be less effective than smaller numbers. This optimal electroporation regimen had no detrimental effect on wound healing. We conclude that electroporation increases the efficiency of transgene expression and may have a role in gene therapy to enhance wound healing. 相似文献