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1.
OBJECTIVE: To examine the relationship between pregnancy incidence and the level of serum E2 during danazol therapy. DESIGN: Danazol was given by 200 mg four times daily for 3 months. Serum E2 level was checked after completing the therapy, but before stopping medication. Patients then were advised to conceive at the appropriate time over a 6-month period. SETTING: Reproductive and Endocrine Laboratory of the Department of Obstetrics and Gynecology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan. PATIENTS: Infertile women with invasive endometriosis receiving conservative surgery and danazol treatment. INTERVENTIONS: Serum E2 is checked before medication and at the end of danazol therapy, but before stopping medication. MAIN OUTCOME MEASURES: Whether pregnancy is related to the change of serum E2 caused by danazol therapy. RESULTS: There were 24 pregnancies in 38 patients with invasive endometriosis after treatment. Pregnant patients had significantly lower serum E2 levels as compared with the nonpregnant patients. CONCLUSIONS: After conservative surgery for invasive endometriosis associated with infertility, the therapeutic period of danazol treatment could be shortened to 3 months. Because there is significant correlation of fecundability and serum E2 after danazol medication, serum E2 could be a guideline for predicting pregnancy or for prolonging or changing of treatment after danazol therapy. 相似文献
2.
ESR spin trapping was used to investigate the reaction of rabbit cytochrome P450 (P450) 1A2 with cumene hydroperoxide. Cumene hydroperoxide-derived peroxyl, alkoxyl, and carbon-centered radicals were formed and trapped during the reaction. The relative contributions of each radical adduct to the composite ESR spectrum were influenced by the concentration of the spin trap. Computer simulation of the experimental data obtained at various 5,5-dimethyl-1-pyrroline N-oxide (DMPO) concentrations was used to quantitate the contributions of each radical adduct to the composite ESR spectrum. The alkoxyl radical was the initial radical produced during the reaction. Experiments with 2-methyl-2-nitrosopropane identified the carbon-centered adducts as those of the methyl radical, hydroxymethyl radical, and a secondary carbon-centered radical. The reaction did not require NADPH-cytochrome P450 reductase or NADPH. It is concluded that the reaction involves the initial homolytic scission of the peroxide O-O bond to produce the cumoxyl radical. Methyl radicals were produced from the beta-scission of the cumoxyl radical. The peroxyl adduct was not observed in the absence of molecular oxygen. We conclude that the DMPO peroxyl radical adduct detected in the presence of oxygen was due to the methylperoxyl radical formed by the reaction of the methyl radical with oxygen. At a higher P450 concentration, a protein-derived radical adduct was also detected. 相似文献
3.
TV Perneger P Chopard FP Sarasin JM Gaspoz C Lovis PF Unger AF Junod FA Waldvogel 《Canadian Metallurgical Quarterly》1997,157(13):1495-1500
OBJECTIVE: To identify patient- and admission-related risk factors for a medically inappropriate admission to a department of internal medicine. METHODS: Cross-sectional study of a systematic sample of 500 admissions to the department of internal medicine of an urban teaching hospital. The appropriateness of each admission and reasons for inappropriate admissions were assessed using the Appropriateness Evaluation Protocol. Risk factors included the time (day of week and holidays) and manner (through emergency department or direct admission) of admission, patient age and sex, health status of patient and spouse, living arrangements, formal home care services, and informal support from family or friends. RESULTS: Overall, 76 (15.2%) hospital admissions were rated as medically inappropriate by the Appropriateness Evaluation Protocol. In multivariate analysis, the likelihood of an inappropriate admission was increased by better physical functioning of the patient (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1-2.1 [for 1 SD in Physical Functioning scores]), lower mental health status of the patient's spouse (OR, 2.6; 95% CI, 1.3-5.6), receipt of informal help from family or friends (OR, 3.3; 95% CI, 1.5-7.2), and hospitalization by one's physician (OR, 3.6; 95% CI, 1.7-7.5). Receiving formal adult home care was not associated with inappropriateness of hospitalization. CONCLUSIONS: Inappropriate admissions to internal medicine wards are determined by a mix of factors, including the patient's health and social environment. In addition, the private practitioners' discretionary ability to hospitalize their patients directly may also favor medically inappropriate admissions. 相似文献
4.
5.
FM Loehrer CP Angst FP Brunner WE Haefeli B Fowler 《Canadian Metallurgical Quarterly》1998,13(3):656-661
BACKGROUND: Elevated homocysteine concentrations have been associated with premature arteriosclerosis and with impairment of key methylation reactions through accumulation of the homocysteine metabolite S-adenosylhomocysteine. In end-stage renal failure high homocysteine concentrations are commonly found but thus far the concentrations of related adenosylated metabolites in plasma have not been assessed. METHODS: In this prospective study we determined plasma homocysteine and related metabolites in 25 patients on regular haemodialysis, and in 40 healthy volunteers. Blood samples from patients were drawn immediately before and in 10 patients additionally after the dialysis session. RESULTS: Folic acid and vitamin B12 in plasma were similar in patients (mean +/- SEM 25+/-2 nmol/l and 400+/-41 pmol/l respectively) and controls (24+/-3 and 324+/-23 respectively). In patients plasma homocysteine, S-adenosylmethionine and S-adenosylhomocysteine were markedly elevated (36.6+/-3.6 micromol/l, 381+/-32nmol/l and 1074+/-55 nmol/l respectively) compared to the control values (6.8+/-0.4 micromol/l, 60+/-3 nmol/l and 24.4+/-1.1 nmol/l respectively) whereas the molar ratio of plasma S-adenosylmethionine and S-adenosylhomocysteine was significantly decreased (0.36+/-0.02 and 2.7+/-0.2 in patients and controls respectively). Haemodialysis failed to normalize the abnormal levels of these metabolites. CONCLUSION: Since the ratio of S-adenosylmethionine : S-adenosylhomocysteine is closely linked to the activity of numerous enzymatic methylation reactions, these results suggest that methylation may be impaired in these patients. 相似文献
6.
AM Zeillemaker FP Mul AA Van Papendrecht P Leguit HA Verbrugh D Roos 《Canadian Metallurgical Quarterly》1996,20(1):87-95
Exposure of Farage, a human B-cell line, to interleukin 4 (IL4) reduced the amount of CD38 antigen on the surface of the cells and in cell lysates. No evidence was obtained for accelerated breakdown, shedding, or internalization of CD38 molecules following IL4 treatment, nor the accumulation of CD38 molecules in the cell interior. The inhibition of protein synthesis with cycloheximide (CXM) diminished the down-regulation of CD38 induced by IL4. CXM decreased the expression of CD38 in Farage cells with arrested mitosis, and IL4 failed to further reduce CD38 expression. Staurosporine, an inhibitor of serine/threonine protein kinases, and H7 (1-(5-isoquinolinylsulfonyl)-2-methylpiperazine), a preferential inhibitor of protein kinase C (PKC), abrogated the effect of IL4 on CD38, while inhibitors of other serine protein kinases W7 (N-(aminohexyl)-5-chloro-1-naphthalenesulfoamide) and H8 (N-(2-[methylamino]ethyl)-5-isoquinolinesulfonamide) failed to interfere with the effect of IL4. Phorbol 12-myristate 13-acetate (PMA), an activator of PKC, resembled IL4 in decreasing the expression of CD38, and either staurosporine or H7 abolished this effect. Genistein, an inhibitor of tyrosine kinases, increased the expression of CD38, but failed to abrogate the inhibitory effect of IL4 on CD38. It is concluded that serine/threonine protein kinases mediated the IL4-induced down-regulation of the expression of CD38 molecules in B cells. 相似文献
7.
FP Cappuccio 《Canadian Metallurgical Quarterly》1997,11(9):571-576
Mortality from coronary heart disease (CHD), stroke and end-stage renal failure are high in South Asian migrants in the UK. This is associated with high prevalence of diabetes and hypertension. These seem to be manifestations of a metabolic syndrome with insulin resistance (hyperinsulinaemia) and central obesity (based on high waist-to-hip ratio rather than on conventional measures of body mass index). This is associated with sedentary lifestyle, high serum triglycerides and low HDL-cholesterol. Mortality from stroke and end-stage renal failure are high in black migrants to the UK (both Caribbeans and West Africans). However, CHD mortality is low in this group. This pattern of mortality is associated with high prevalence of hypertension and diabetes. This group tends to be obese (particularly women) according to conventional measures of body mass index and to have hyperinsulinaemia, low serum triglycerides and high HDL-cholesterol. Conventional risk factors such as cigarette smoking and hypercholesterolaemia are less prevalent in ethnic minority populations in the United Kingdom and unlikely to explain the differences seen between groups, although each risk factor is likely to contribute to the variation in vascular disease within each group. There is difficulty in reconciling the results of migration studies (eg, from rural to urban environments) pointing to major environmental influences on the changes in cardiovascular risk factors with the consistent pattern of disease of ethnic groups across the world and in subsequent generations, suggesting a certain degree of genetic susceptibility. Important environment-gene interplays might be underlying some of these processes. The detection and management of hypertension and diabetes are still unsatisfactory in inner city areas and show variations by ethnic origin. Strategies for the control of CHD and stroke adopted in European countries directed mostly to white populations may be inappropriate for ethnic minority populations. 相似文献
8.
Laparoscopic cholecystectomy and gallbladder cancer: a diagnostic and therapeutic dilemma 总被引:1,自引:0,他引:1
F Razzetta G Borgonovo A Cagnazzo C Bianchi FP Mattioli 《Canadian Metallurgical Quarterly》1997,23(1):84-85
The correct treatment strategy of patients with unsuspected gallbladder cancer undergoing laparoscopy, and the prevention of delayed diagnosis are current issues. We report a case of late diagnosis with umbilical metastasis and poor survival. A policy of careful inspection of the gallbladder and a cautious strategy in the case of gross alteration of its external morphology seems advisable during laparoscopic cholecystectomy. Although no agreement exists concerning the best treatment in the event of delayed diagnosis, the adopted strategy is contingent on patient status, disease stage and the possibility of performing appropriate follow-up. 相似文献
9.
TG Doak DJ Witherspoon FP Doerder K Williams G Herrick 《Canadian Metallurgical Quarterly》1997,101(2):75-86
BACKGROUND: Accessory function (AF) is one way antigen presenting cells generate sufficient secondary signals for optimal T-cell proliferation and IL-2 production. In general, alveolar macrophages (AM) are inferior accessory cells in comparison to monocytes whereas in sarcoidosis AF of AM is increased. METHODS: We compared the accessory index (AI) of AM and peripheral blood monocytes (PBM) of 41 patients with inactive sarcoidosis (SAR I, n = 12); active sarcoidosis with new or progressing symptoms (SAR II, n = 19), active sarcoidosis with spontaneous remission (SAR III, n = 10), tuberculosis (TB, n = 12), hypersensitivity pneumonitis (HP, n = 12), Wegener's disease (WD, n = 2), undefined alveolitis (UA, n = 8) and chronic obstructive pulmonary disease (COPD, n = 6) by employing the histoincompatibility-insensitive Jurkat cells as indicator cells. RESULTS: Compared with the controls (1.08 +/- 0.3) AMs of all groups but SAR I (AI: 0.96 +/- 0.42) exhibited significantly increased AIs (SAR II: 3.6 +/- 3.9; SAR III: 3.2 +/- 2.4; TB: 2.8 +/- 2.2; HP: 3 +/- 2; UA: 2.7 +/- 2.3; COPD: 3.1 +/- 2.2; p < 0.05 for all comparisons). Only in HP, AI of PBM was significantly increased compared with controls (3 +/- 1.5, 1.3 +/- 0.5, respectively; p < 0.001). Alveolar macrophages from patients with arcoidosis, TB, and HB express the costimulatory molecule CD80 on their surface and anti-CD80 antibodies inhibited the IL-2 release of Jurkat cells in this system to 59 +/- 27%. CONCLUSIONS: Our data demonstrate that AM from patients with various diseases have the capability to act as competent accessory cells and that the reported accessory function of these cells is at least in part mediated by the expression of CD80. 相似文献
10.
Chronic bone infection, as attends periodontitis, is often complicated by severe osteolysis. While LPS is believed to be central to the pathogenesis of the osteolytic lesion, the mechanisms by which this bacteria-derived molecule promotes bone resorption are unknown. We find that LPS induces bone marrow macrophages (BMMs) to express c-src, a protooncogene product that we demonstrate is a specific marker of commitment to the osteoclast phenotype. We next turned to possible soluble mediators of LPS-induced c-src. Of a number of osteoclastogenic cytokines tested, only TNF-alpha mirrors the c-src-enhancing effect of LPS. Suggesting that LPS augmentation of c-src is TNF-mediated, endotoxin sequentially induces BMM expression of TNF, followed by c-src. TNF and c-src expression, by cultured BMMs derived from LPS-injected mice, reflects duration of exposure to circulating endotoxin, intimating that endotoxin's effect in vivo is also mediated by TNF. Consistent with these findings, thalidomide (which antagonizes TNF action) attenuates c-src induction by LPS. An anti-TNF antibody blocks LPS enhancement of c-src mRNA, validating the cytokine's modulating role in vitro. Using BMMs of TNF receptor-deleted mice, we demonstrate that TNF induction of c-src is transmitted through the cytokine's p55, but not p75, receptor. Most importantly, LPS administered to wild-type mice prompts osteoclast precursor differentiation, manifest by profound osteoclastogenesis in marrow cultured ex vivo, and by a profusion of marrow-residing cells expressing the osteoclast marker tartrate resistant acid phosphatase, in vivo. In contrast, LPS does not substantially enhance osteoclast proliferation in mice lacking the p55TNF receptor, confirming that LPS-induced osteoclastogenesis is mediated by TNF in vivo via this receptor. Thus, therapy targeting TNF and/or its p55 receptor presents itself as a means of preventing the osteolysis of chronic bacterial infection. 相似文献