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31.
32.
目的 探究灯盏花素与洛伐他汀联用对大鼠体内药动学的影响,从代谢酶的角度揭示灯盏花素对洛伐他汀药动学产生影响的机制。方法 采用探针药物法及RT-HPLC法测定咪达唑仑在肝微粒体孵育体系中的浓度,评价灯盏花素与洛伐他汀联用对CYP3A4酶活性的影响。通过RT-PCR反应来检测CYP3A4酶mRNA基因表达,采用Western blot法,从蛋白翻译水平上分析灯盏花素与洛伐他汀联用对大鼠肝脏CYP3A4蛋白表达的影响。结果 洛伐他汀与灯盏花素联合用药后,洛伐他汀在大鼠体内的血药浓度显著升高,从0.39 mg?L-1 上升到1.08 mg?L-1 ,清除率从3.36L?h-1?kg-1降低到1.08L?h-1?kg-1,药物半衰期从5.0h延长到6.2h,联合给药后洛伐他汀的AUC从2.42mg?L-1?h-1上升到4.22mg?L-1?h-1。洛伐他汀组与空白组比较CYP3A4酶活性均没有明显变化;灯盏花素组及灯盏花素联合洛伐他汀组与空白组比较发现均抑制CYP3A4酶活性;灯盏花素与灯盏花素联合洛伐他汀组CYP3A4酶mRNA 表达量均较空白组显著降低;CYP3A4酶蛋白含量结果表明,洛伐他汀组与灯盏花素联合洛伐他汀组与空白组比较CYP3A4酶蛋白含量均没有明显变化。结论 洛伐他汀与灯盏花素联用,灯盏花素通过抑制其基因转录水平抑制CYP3A4的活性,使大鼠体内药动学过程发生变化,洛伐他汀药物的代谢减慢。 相似文献
33.
Kristina A. Thayer Kyla W. Taylor Stavros Garantziotis Shepherd H. Schurman Grace E. Kissling Dawn Hunt Brenda Herbert Rebecca Church Rachael Jankowich Mona I. Churchwell Richard C. Scheri Linda S. Birnbaum John R. Bucher 《Environmental health perspectives》2016,124(4):437-444
Background:
Bisphenol A (BPA) is a high-production-volume chemical associated with a wide range of health outcomes in animal and human studies. BPA is used as a developer in thermal paper products, including cash register receipt paper; however, little is known about exposure of cashiers to BPA and alternative compounds in receipt paper.Objective:
We determined whether handling receipt paper results in measurable absorption of BPA or the BPA alternatives bisphenol S (BPS) and 4-hydroxyphenyl 4-isoprooxyphenylsulfone (BPSIP).Methods:
Cashiers (n = 77) and non-cashiers (n = 25) were recruited from the Raleigh–Durham–Chapel Hill region of North Carolina during 2011–2013. Receipts were analyzed for the presence of BPA or alternatives considered for use in thermal paper. In cashiers, total urine and serum BPA, BPS, and BPSIP levels in post-shift samples (collected ≤ 2 hr after completing a shift) were compared with pre-shift samples. Levels of these compounds in urine from cashiers were compared to levels in urine from non-cashiers.Results:
Each receipt contained 1–2% by weight of the paper of BPA, BPS, or BPSIP. The post-shift geometric mean total urinary BPS concentration was significantly higher than the pre-shift mean in 33 cashiers who handled receipts containing BPS. The mean urine BPA concentrations in 31 cashiers who handled BPA receipts were as likely to decrease as to increase after a shift, but the mean post-shift concentrations were significantly higher than those in non-cashiers. BPSIP was detected more frequently in the urine of cashiers handling BPSIP receipts than in the urine of non-cashiers. Only a few cashiers had detectable levels of total BPA or BPS in serum, whereas BPSIP tended to be detected more frequently.Conclusions:
Thermal receipt paper is a potential source of occupational exposure to BPA, BPS, and BPSIP.Citation:
Thayer KA, Taylor KW, Garantziotis S, Schurman SH, Kissling GE, Hunt D, Herbert B, Church R, Jankowich R, Churchwell MI, Scheri RC, Birnbaum LS, Bucher JR. 2016. Bisphenol A, bisphenol S, and 4-hydroxyphenyl 4-isoprooxyphenylsulfone (BPSIP) in urine and blood of cashiers. Environ Health Perspect 124:437–444; http://dx.doi.org/10.1289/ehp.1409427 相似文献34.
35.
Aim: A short vaccination protocol against hepatitis B was compared to the standard approach in patients under haemodialysis who were primarily non-responsive to the vaccine.
Methods: This randomized, controlled open trial included 51 chronic haemodialysis subjects previously vaccinated against hepatitis B and with anti-HBs levels of less than 10 IU/mol/L. Twenty-six patients received 20 µg i.m. once a week for 8 weeks (short protocol) and 25 subjects three doses of 40 µg i.m. at months 0, 1 and 6 (standard protocol). Clinical and laboratory data were compared between responders and non-responders. A logistic regression model included selected parameters to assess risk factors for non-seroconversion.
Results: Seroconversion rates to vaccine at 2 months were 80% and 78% in the short and standard protocol groups, respectively ( P = 0.99). Median of anti-HBs levels were similar up to 6 months of follow up, but patients in the standard protocol showed a trend to higher anti-HBs in month 3 and a more steady decline in antibody titres. Non-responders were older, had longer duration of dialysis and a higher prevalence of a prior renal transplant and hepatitis C. In multivariate analysis, only advanced age and hepatitis C remained independently associated with non-responsiveness to vaccination.
Conclusion: In haemodialysis patients, a short vaccination protocol against hepatitis B did not provide any benefit compared to the standard approach with respect to peak anti-HBs titres or a higher rate of seroprotection at the end of follow up. Other strategies to increase seroconversion rates should be explored, especially in the elderly and in patients with hepatitis C. 相似文献
Methods: This randomized, controlled open trial included 51 chronic haemodialysis subjects previously vaccinated against hepatitis B and with anti-HBs levels of less than 10 IU/mol/L. Twenty-six patients received 20 µg i.m. once a week for 8 weeks (short protocol) and 25 subjects three doses of 40 µg i.m. at months 0, 1 and 6 (standard protocol). Clinical and laboratory data were compared between responders and non-responders. A logistic regression model included selected parameters to assess risk factors for non-seroconversion.
Results: Seroconversion rates to vaccine at 2 months were 80% and 78% in the short and standard protocol groups, respectively ( P = 0.99). Median of anti-HBs levels were similar up to 6 months of follow up, but patients in the standard protocol showed a trend to higher anti-HBs in month 3 and a more steady decline in antibody titres. Non-responders were older, had longer duration of dialysis and a higher prevalence of a prior renal transplant and hepatitis C. In multivariate analysis, only advanced age and hepatitis C remained independently associated with non-responsiveness to vaccination.
Conclusion: In haemodialysis patients, a short vaccination protocol against hepatitis B did not provide any benefit compared to the standard approach with respect to peak anti-HBs titres or a higher rate of seroprotection at the end of follow up. Other strategies to increase seroconversion rates should be explored, especially in the elderly and in patients with hepatitis C. 相似文献
36.
S H Schurman N Sharon R A Goldschmidt E F Scanlon 《Archives of surgery (Chicago, Ill. : 1960)》1990,125(2):179-182
We present a new method for detection of micrometastases to axillary lymph nodes and estrogen receptor determination. Cellular suspensions from primary infiltrating ductal breast carcinoma or level I axillary lymph nodes of patients who underwent mastectomies were obtained, by loosely grinding fresh tumors or lymph nodes through a grid and then transferring the matrix to a slide using cytocentrifugation. Tumor samples were analyzed for estrogen receptor status using an immunocytochemical kit and compared with the dextran-coated charcoal method. Thirty-eight of 48 correlated (20 were estrogen positive, and 18 were estrogen negative). Seven of 46 were estrogen positive while results from the dextran-coated charcoal method were estrogen negative. One of 46 was estrogen negative, while the results from the dextran-coated charcoal method were estrogen positive. Lymph node slide preparations were stained to detect tumor cells using antikeratin monoclonal antibodies. Three of 8 node-negative patients were found to have micrometastases. Four of 15 node-positive patients had additional nodes with tumor. Our method combines the advantages of serial sectioning and immunohistochemical staining. 相似文献
37.
V Venkatramani S Pillai S Marathe SA Rege JV Hardikar 《Annals of the Royal College of Surgeons of England》2009,91(5):W13-W14
Introduction
Breast gangrene has been reported as a complication following puerperal sepsis, breast surgery, nipple piercings, warfarin toxicity, etc. We report a case of primary breast gangrene in an HIV-positive individual which, to the best of our knowledge, is the first of its kind.Case report
A 40-year-old previously healthy woman presented with fulminating left breast gangrene. She was detected to be HIV positive. Mastectomy was performed. The detailed management of the condition is discussed.Conclusion
Severe necrotising infections may be initial manifestations of HIV infection and patients with such infections should be screened for HIV. 相似文献38.
Background
To present an episodic random utility model that unifies time trade-off and discrete choice approaches in health state valuation. 相似文献39.
PT Clayton M Doig S Ghafari C Meaney C Taylor JV Leonard M Morris AW Johnson 《Archives of disease in childhood》1998,79(2):109-115
OBJECTIVE: To establish criteria for the diagnosis of medium chain acyl-CoA dehydrogenase (MCAD) deficiency in the UK population using a method in which carnitine species eluted from blood spots are butylated and analysed by electrospray ionisation tandem mass spectrometry (ESI-MS/MS). DESIGN: Four groups were studied: (1) 35 children, aged 4 days to 16.2 years, with proven MCAD deficiency (mostly homozygous for the A985G mutation, none receiving carnitine supplements); (2) 2168 control children; (3) 482 neonates; and (4) 15 MCAD heterozygotes. RESULTS: All patients with MCAD deficiency had an octanoylcarnitine concentration ([C8-Cn]) > 0.38 microM and no accumulation of carnitine species > C10 or < C6. Among the patients with MCAD deficiency, the [C8-Cn] was significantly lower in children > 10 weeks old and in children with carnitine depletion (free carnitine < 20 microM). Neonatal blood spots from patients with MCAD deficiency had a [C8-Cn] > 1.5 microM, whereas in heterozygotes and other normal neonates the [C8-Cn] was < 1.0 microM. In contrast, the blood spot [C8-Cn] in eight of 27 patients with MCAD deficiency > 10 weeks old fell within the same range as five of 15 MCAD heterozygotes (0.38-1.0 microM). However, the free carnitine concentrations were reduced (< 20 microM) in the patients with MCAD deficiency but normal in the heterozygotes. CONCLUSIONS: Criteria for the diagnosis of MCAD deficiency using ESI-MS/MS must take account of age and carnitine depletion. If screening is undertaken at 7-10 days, the number of false positive and negative results should be negligible. Because there have been no instances of death or neurological damage following diagnosis of MCAD deficiency in our patient group, a strong case can be made for neonatal screening for MCAD deficiency in the UK. 相似文献
40.
We previously reported on a 43-year-old patient with Wiskott-Aldrich syndrome (WAS) who experienced progressive clinical improvement and revertant T-cell mosaicism. Deletion of the disease-causing 6-bp insertion was hypothesized to have occurred by DNA polymerase slippage. We now describe 2 additional patients from the same family who also had revertant T lymphocytes that showed selective in vivo advantage. Somatic mosaicism was demonstrated on leukocytes cryopreserved in the first patient when he was 22 years old, 11 years before his death from kidney failure. The second patient is now 16 years old, has a moderate clinical phenotype, and developed revertant cells after the age of 14 years. These results support DNA polymerase slippage as a common underlying mechanism, and they indicate that T-cell mosaicism may have different clinical effects in WAS. 相似文献