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991.
Thyrotropin receptor autoantibodies are associated with continued thyrotropin suppression in treated euthyroid Graves' disease patients 总被引:3,自引:0,他引:3
Brokken LJ Wiersinga WM Prummel MF 《The Journal of clinical endocrinology and metabolism》2003,88(9):4135-4138
Antithyroid treatment effectively restores euthyroidism in patients with Graves' hyperthyroidism. After a few months of treatment, patients are clinically euthyroid with normal levels of thyroid hormones, but in many patients TSH levels remain suppressed. We postulated that TSH receptor autoantibodies could directly suppress TSH secretion, independently from thyroid hormone levels, via binding to the pituitary TSH receptor. To test this hypothesis, we prospectively followed 45 patients with Graves' hyperthyroidism who were treated with antithyroid drugs. Three months after reaching euthyroidism, blood was drawn for the analysis of thyroid hormones, TSH, and TSH binding inhibitory Ig (TBII) levels. After 6.7 +/- 1.5 months since start of antithyroid treatment, 20 patients still had detectable TBII levels, and 25 had become TBII negative. The two groups had similar levels of free T(4) and T(3), but TBII-positive patients had lower TSH values than TBII-negative patients: median 0.09 (range < 0.01-4.30) mU/liter vs. 0.84 (0.01-4.20; P = 0.015). In addition, TSH levels correlated only with TBII titers (r = -0.424; P = 0.004), and not with free T(4) or T(3) values. Our findings suggest that TBII suppress TSH secretion independently of thyroid hormone levels, most likely by binding to the pituitary TSH receptor. 相似文献
992.
Furumoto-Dawson Al Pandey DK Elliott WJ de Leon Mendes CF Al-Hani AJ Hollenberg S Camba N Wicklund R Black HR 《Journal of clinical hypertension (Greenwich, Conn.)》2003,5(1):38-52
Hypertension is an important, modifiable risk for cardiovascular disease. The Women Take Heart study, a prospective, community-based cohort study of risk factors for heart disease, provides an opportunity to examine prevalence, awareness, and control of hypertension specifically in women. In 1992, 5932 women, age 35 and older (mean age, 52.9; 86% white, 9% African American, 5% other) and free of active heart disease symptoms for 3 months, were recruited through Chicago area public announcements, and their baseline examination data analyzed. Overall, 47.6% were hypertensive (systolic blood pressure 140 mm Hg or diastolic blood pressure 90 mm Hg, or self-report). Only 17.3% reported being hypertensive; in 63.2% of all hypertensive women, the hypertension was undetected or unacknowledged. Blood pressure was controlled to <140/90 mm Hg in 24.1% of self-reported hypertensives. Results from this study and national surveys indicate that hypertension detection and control remain major public health challenges in preventing cardiovascular disease in older women. 相似文献
993.
Woudri Oosthuizen Leoné Malan Jacobus D. Scheepers Marike Cockeran Nicolaas T. Malan 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2016,38(6):526-532
The behavioral defense coping response (DefS) as a measure of coping with emotional stress may increase alcohol intake (gamma glutamyl transferase (γGT)), the risk for coronary artery disease (CAD) and insulin sensitivity (homeostasis model assessment, HOMA). We assessed associations between coping and cardiometabolic risk markers in a bi-ethnic cohort (N = 390) from South Africa. Ambulatory blood pressure (BP) and ECG, fasting blood and coping scores were obtained. Africans, and mostly when utilizing DefS, showed higher 24h BP, a low-grade inflammatory state, central obesity, increased HOMA [4.07 (3.66, 4.47)] and more ST events compared to their Caucasian counterparts. ROC γ-GT analyses predicting 24-h ambulatory hypertension showed a higher γ-GT cut-point in Africans (55.4 U/l) than in Caucasians (19.5 U/l). Odds ratios (ORs) of γ-GT cut-points predicting 24-h ambulatory hypertension was evident in DefS African men [OR: 7.37 (95% CI: 6.71–8.05), p = 0.003] and in DefS Caucasians, albeit at a lower γ-GT cut-point (19.5 U/l). Higher γ-GT cut-points in DefS Africans or Caucasians were not associated with HOMA > 3. DefS accompanied by alcohol abuse in taxing emotional situations, if no social support is forthcoming, underscores a profile of reduced coronary perfusion. It may enhance vasoconstriction of the coronary arteries, with compensatory increases in BP, and induce a risk for future coronary artery disease. 相似文献
994.
Alexandre Abizaid Aurea J Chaves Martin B Leon Karl Hauptmann Roxana Mehran Alexandra J Lansky William Baumbach Hari Shankar Ralf Muller Fausto Feres Amanda G M R Sousa J Eduardo Sousa Eberhard Grube 《Catheterization and cardiovascular interventions》2007,70(5):654-660
OBJECTIVES: The ETHOS I trial was the first in-human experience evaluating the safety and efficacy of two different release formulations of the 17-beta estradiol-eluting R-Stent versus uncoated control stents for the treatment of patients with single de novo native coronary lesions. BACKGROUND: Estrogens were reported to inhibit neointimal proliferation and to accelerate endothelial regeneration after coronary angioplasty and thus could be an ideal compound to deliver on a stent for the purpose of reducing in-stent restenosis. METHODS: Ninety-five patients were randomized to receive a slow-release (n = 32) or the moderate release (n = 31) formulations or the bare metal stent (n = 32). The primary end point was the 6-month percent in-stent volume obstruction by intravascular ultrasound (IVUS). RESULTS: Diabetes was present in 29.5% of patients; the mean reference vessel diameter was 2.90 mm; and the mean lesion length was 13.5 mm. Primary endpoint, 6-month percent in-stent volume obstruction by IVUS, did not differ significantly between the 3 groups (31% +/- 14%, 33% +/- 11%, and 31% +/- 14%, P = 0.83). Secondary endpoints also did not differ significantly between the groups including 6-month rates of in-lesion binary angiographic restenosis (13.3%, 14.3%, and 12.5%, P = 0.98), in-stent late loss (0.82 +/- 0.49 mm, 0.86 +/- 0.53 mm, and 0.84 +/- 0.46 mm, P = 0.97), target lesion revascularization (12.5%, 6.9%, and 6.5%, P = 0.64), and major adverse cardiac events (18.8%, 10.3%, and 6.5%, P = 0.31). CONCLUSIONS: In this first-in-man randomized trial, the 17-beta estradiol-eluting R-Stent, in either slow- or moderate-release formulations, was well-tolerated, but showed no benefit for treatment of coronary lesions when compared to controls. 相似文献
995.
Hatch SL Feinstein L Link BG Wadsworth ME Richards M 《The journals of gerontology. Series B, Psychological sciences and social sciences》2007,62(6):S404-S414
OBJECTIVE: Evidence shows education positively impacts cognitive ability. However, researchers have given little attention to the potential impact of adult education on cognitive ability, still malleable in midlife. The primary study aim was to examine whether there were continuing effects of education over the life course on midlife cognitive ability. METHODS: This study used data from the Medical Research Council National Survey of Health and Development, also known as the British 1946 birth cohort, and multivariate regression to estimate the continuing effects of adult education on multiple measures of midlife cognitive ability. RESULT: Educational attainment completed by early adulthood was associated with all measures of cognitive ability in late midlife. The continued effect of education was apparent in the associations between adult education and higher verbal ability, verbal memory, and verbal fluency in late midlife. We found no association between adult education and mental speed and concentration. Discussion: Associations between adult education and midlife cognitive ability indicate wider benefits of education to health that may be important for social integration, well-being, and the delay of cognitive decline in later life. 相似文献
996.
Doyun?ParkEmail author William?Southern Manuela?Calvo Margarita?Kushnir Clemencia?Solorzano Mark?Sinnet Henny?H.?Billett 《Journal of general internal medicine》2016,31(2):182-187
BACKGROUND
Low molecular weight heparins (LMWHs) have been cautiously used in patients with chronic kidney disease (CKD) due to fear of accumulation. Dalteparin, however, has shown minimal tendency to accumulate in patients with CKD and may be safe to use in this patient population.OBJECTIVE
We compared the incidence of clinically significant bleeding in patients with CKD receiving therapeutic doses of dalteparin to that of patients with CKD receiving therapeutic doses of UFH.DESIGN
This was a retrospective cohort study.SUBJECTS
Inpatients with CKD (GFR?<?60 ml/min) who were treated with therapeutic dalteparin or UFH were included in the studyMAIN MEASURES
Primary outcome was major bleeding within 10 days of anticoagulation, identified by ICD-9 code and confirmed by chart review. Demographic characteristics, laboratory values, comorbidities, prior bleeding history and inpatient medications were extracted for each admission from the electronic medical record. Logistic regression models were created to examine the association between choice of anticoagulant and bleeding rates, after adjustment for demographic and clinical characteristics.KEY RESULTS
Dalteparin-treated patients were significantly less likely to experience a major bleed than patients treated with UFH (1.14 % vs. 3.49 %, p?<?0.001). The reduced likelihood of bleeding associated with dalteparin treatment remained significant after adjustment for patient characteristics (HR 0.39, 95 % CI: 0.21–0.70, p?<?0.0001). A stratified analysis for subgroups with GFR< 30 mL/min and with GFR between 30 and 60 mL/min showed that dalteparin was still associated with lower odds of bleeding compared to treatment with unfractionated heparin, but the difference was nonsignificant for GFR< 30 (HR 0.35, 95 % CI: 0.11–1.15), even after adjustment (OR 0.37, 95 % CI: 0.11–1.22).CONCLUSION
In patients with CKD, treatment with therapeutic dose dalteparin was associated with lower rates of bleeding than treatment with unfractionated heparin. For patients with severe CKD (GFR< 30), dalteparin was shown to be at least as safe as unfractionated heparin.997.
Katherine?H.?SaundersEmail author Rekha?B.?Kumar Leon?I.?Igel Louis?J.?Aronne 《Current atherosclerosis reports》2016,18(7):36
Obesity is a growing epidemic in the USA with over one third of adults presently classified as obese. Obesity-related comorbidities include many leading causes of preventable death such as heart disease, stroke, type 2 diabetes, and certain types of cancer. Modest weight loss of 5–10 % of body weight is sufficient to produce clinically relevant improvements in cardiovascular disease risk factors among patients with overweight and obesity. Until recently, there were limited pharmacologic options approved by the Food and Drug Administration to treat obesity. Phentermine/topiramate ER and lorcaserin were approved in 2012, and naltrexone SR/bupropion SR and liraglutide 3.0 mg were approved in 2014. This article reviews recent literature in the field of Obesity Medicine and highlights important findings from clinical trials. Future directions in the pharmacologic management of obesity are presented along with new diabetes medications that promote weight loss and reduce cardiovascular mortality. 相似文献
998.
Janarthanan Sathananthan Dale J. Murdoch Brian R. Lindman Alan Zajarias Wael A. Jaber Paul Cremer David Wood Robert Moss Anson Cheung Jian Ye Rebecca T. Hahn Aaron Crowley Martin B. Leon Michael J. Mack John G. Webb 《JACC: Cardiovascular Interventions》2018,11(12):1154-1160
Objectives
The aim of this study was to assess the implications of concomitant tricuspid regurgitation (TR) in patients undergoing valve-in-valve (VIV) transcatheter aortic valve replacement.Background
Patients undergoing VIV transcatheter aortic valve replacement with concomitant TR may have worse outcomes, and optimal management remains undetermined.Methods
The multicenter PARTNER 2 (Placement of Aortic Transcatheter Valves) VIV trial enrolled patients with symptomatic degenerated surgical aortic bioprostheses who were at high risk for reoperation. Outcomes were assessed between patients with mild or no TR versus moderate or severe TR.Results
A total of 237 patients underwent VIV procedures (mean age 78.7 ± 10.8 years, mean Society of Thoracic Surgeons score 9.1 ± 4.8%). In this cohort, 162 patients (68.4%) had mild or no TR, and 75 patients (31.6%) had moderate or severe TR. Although there was no difference in New York Heart Association functional class III or IV symptomatic status (89.3% vs. 91.4%; p = 0.62) or moderate or severe right ventricular dysfunction (9.4% vs. 16.9%; p = 0.11), patients with moderate or severe TR were more likely to be at high surgical risk, with a Society of Thoracic Surgeons score of >8 (62.7% vs 46.9%; p = 0.02). There was no difference in a composite endpoint of death and rehospitalization between moderate or severe TR and mild or no TR, either at 30 days (10.7% vs. 9.9%; p = 0.85) or at 1-year follow-up (24.1% vs. 23.2%; p = 0.80). There was a significant reduction in overall moderate or severe TR from baseline at 30 days (31.1% vs. 21.1%; p = 0.002), which was sustained at 1-year follow-up (38.0% vs. 22.8%; p = 0.004).Conclusions
Despite higher predicted surgical risk, the presence of TR was not a predictor of long-term outcomes. Importantly, there was significant reduction in TR severity at both short- and long-term follow-up. In selected patients undergoing VIV transcatheter aortic valve replacement, it may be appropriate to conservatively manage concomitant TR. 相似文献999.
J P Després J Gagnon J Bergeron C Couillard A S Leon D C Rao J S Skinner J H Wilmore C Bouchard 《Clinical biochemistry》1999,32(3):157-165
OBJECTIVES: Examine the reproducibility of plasma lipid and lipoprotein measurements in the HERITAGE Family Study. DESIGN AND METHODS: In a sample of 379 subjects (191 men and 188 women), reproducibility was determined for lipids, lipoproteins (done on two occasions) and post-heparin lipase assays using an Intracenter Quality Control study by generating split samples from an additional 60 subjects (35 men and 25 women), which were assayed in a blind fashion by the lipid core laboratory. Reproducibility was estimated using intraclass correlation coefficients (ICC) for the selected variables. Analytical error (ANER) and coefficient of variation (CV) were also calculated. Day-to-day variation for 10 variables including plasma cholesterol and triglycerides (TG), HDL-cholesterol and its subfractions HDL2-cholesterol and HDL3-cholesterol, LDL-cholesterol and VLDL-cholesterol, as well as apoprotein (apo) A-I, apo B, and LDL-apo B were assessed. RESULTS: In the HERITAGE study, all lipid and lipoprotein variables had ICC above 0.79. Plasma VLDL-cholesterol (31 %) and TG (23%) levels, which are well known to be highly variable from one day to another, had CVs greater than 20%. Other variables had CVs lower than 10% except for HDL2-cholesterol which reached 16%. In the intracenter reliability sub-study, the measurement errors were found to be low except for HDL2-cholesterol. For the lipases, the reproducibility of repeated samples was very high, with ICC over 0.95. The within-assay CV corresponded to 2.1 and 5.3% for hepatic lipase (HL) and lipoprotein lipase (LPL), respectively, whereas the between-assay CV reached 8-12% for HL and about 15% for LPL. Due to the complexity of these two assays, the results are considered to be quite satisfactory. CONCLUSIONS: The reproducibility of plasma lipid and lipoprotein measurements, as well as of post-heparin lipase activities, is good in the multicenter HERITAGE Family Study. In addition, the well-documented gender difference in the plasma lipoprotein profile was confirmed in the present study, women having lower fasting triglyceride and LDL-cholesterol levels than men as well as reduced cholesterol/HDL-cholesterol and increased HDL2-cholesterol/ HDL3-cholesterol ratios compared to men. Results of the present study support the notion that the higher LPL and low HL activities found in women compared to men are important factors contributing to explain gender difference in the lipoprotein profile. However, additional factors not examined in the present study are involved beyond the contribution of post-heparin lipase to the sex dimorphism in plasma lipoprotein levels. 相似文献
1000.
Yan-Qiong Xiong Leon Iri Kupferwasser Philip M. Zack Arnold S. Bayer 《Antimicrobial agents and chemotherapy》1999,43(7):1737-1742
Optimal treatment strategies for serious infections caused by Staphylococcus aureus have not been fully characterized. The combination of a beta-lactam plus an aminoglycoside can act synergistically against S. aureus in vitro and in vivo. MiKasome, a new liposome-encapsulated formulation of conventional amikacin, significantly prolongs serum half-life (t1/2) and increases the area under the concentration-time curve (AUC) compared to free amikacin. Microbiologic efficacy and left ventricular function, as assessed by echocardiography, were compared in animals administered either oxacillin alone or oxacillin in combination with conventional amikacin or MiKasome in a rabbit model of experimental endocarditis due to S. aureus. In vitro, oxacillin, combined with either free amikacin or MiKasome, prevented the bacterial regrowth observed with aminoglycosides alone at 24 h of incubation. Rabbits with S. aureus endocarditis were treated with either oxacillin alone (50 mg/kg, given intramuscularly three times daily), oxacillin plus daily amikacin (27 mg/kg, given intravenously twice daily), or oxacillin plus intermittent MiKasome (160 mg/kg, given intravenously, a single dose on days 1 and 4). The oxacillin-alone dosage represents a subtherapeutic regimen against the infecting strain in the endocarditis model (L. Hirano and A. S. Bayer, Antimicrob. Agents Chemother. 35:685-690, 1991), thus allowing recognition of any enhanced bactericidal effects between oxacillin and either aminoglycoside formulation. Treatment was administered for either 3 or 6 days, and animals were sacrificed after each of these time points or at 5 days after a 6-day treatment course (to evaluate for posttherapy relapse). Left ventricular function was analyzed by utilizing serial transthoracic echocardiography during treatment and posttherapy by measurement of left ventricular fractional shortening. At all sacrifice times, both combination regimens significantly reduced S. aureus vegetation counts versus control counts (P < 0.05). In contrast, oxacillin alone did not significantly reduce S. aureus vegetation counts after 3 days of therapy. Furthermore, at this time point, the two combinations were significantly more effective than oxacillin alone (P < 0.05). All three regimens were effective in significantly decreasing bacterial counts in the myocardium during and after therapy compared to controls (P < 0.05). In kidney and spleen abscesses, all regimens significantly reduced bacterial counts during therapy (P < 0.0001); however, only the combination regimens prevented bacteriologic relapse in these organs posttherapy. By echocardiographic analysis, both combination regimens yielded a significant physiological benefit by maintaining normal left ventricular function during treatment and posttherapy compared with oxacillin alone (P < 0.001). These results suggest that the use of intermittent MiKasome (similar to daily conventional amikacin) enhances the in vivo bactericidal effects of oxacillin in a severe S. aureus infection model and preserves selected physiological functions in target end organs. 相似文献