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71.
The monoclonal antibody 5B5 reacts with the beta subunit of proline-4- hydroxylase, the enzyme which catalyses the formation of 4-hydroxyl proline in collagen and other proteins with collagen-like amino acid sequences. This study aims to assess the production and tissue distribution of this enzyme in normal and diseased synovia from patients with various joint diseases, on the basis that it is a putative marker of collagen-producing cells and, therefore, in this context, of fibroblasts. Sections from five normal, 10 osteoarthritic (OA) and 26 rheumatoid arthritic (RA) synovia were labelled with a mouse monoclonal antibody to proline-4-hydroxylase. The enzyme was found to be expressed by a proportion of synovial intimal cells and by fibroblasts in the underlying connective tissue in normal, OA and RA synovia. Labelling was more pronounced in OA and RA cases. The intimal cells labelling positively showed type B synoviocyte morphology, which was confirmed by subsequent double immunolabelling with 5B5 and antibody against type IV collagen using immunocytochemistry and immunoelectron microscopy.   相似文献   
72.

Introduction

Reoperative parathyroidectomy is required when there is persistent or recurrent hyperparathyroidism following the initial surgery (at least 5% of parathyroidectomies nationally). By convention, ‘persistent disease’ is defined as the situation where the patient has not been cured by the first operation. The term ‘recurrent hyperparathyroidism’ is used when the patient was confirmed to be biochemically cured for six months from the first operation but has hyperparathyroidism after this date. Reoperative surgery is associated with higher rates of postoperative complications as well as a greater rate of failure to cure. The aim of our study was to review our departmental experience of reoperative parathyroidectomy, with a view to identify patterns of disease persistence and recurrence.

Methods

Using a departmental database, patients were identified who had undergone reoperative parathyroidectomy between 2006 and 2014. All the pre, intra and postoperative information was documented including the operative note so as to record the location of the abnormal parathyroid gland found at reoperation.

Results

Almost two-thirds (63%) of patients had negative, equivocal or discordant conventional imaging so secondary investigative tools were required frequently. The majority of abnormal glands were found in eutopic locations. The most common locations for ectopic glands were intrathyroidal, mediastinal and intrathymic. A third (33%) of the patients had multigland disease and over a quarter (28%) had coexisting thyroid disease.

Conclusions

Persistent hyperparathyroidism represents a challenging patient subgroup for which access to all radiological modalities and intraoperative parathyroid hormone monitoring are required. Patient selection for reintervention is a key determinant in the reoperation cure rate.  相似文献   
73.
Central obesity is a known cardiovascular risk factor and measures of visceral obesity are known to predict atherosclerosis. This study sought to explore the association between various anthropometric measures and markers of subclinical atherosclerosis (MoSCA) among low risk healthy individuals. Multi-Ethnic Study of Atherosclerosis (MESA) is a population-based study of Caucasian (38%), Afro-American (28%), Chinese (22%) and Hispanic (12%) subjects, aged 45–84 years, free from clinical cardiovascular disease. We performed a post hoc analysis of the limited access dataset of MESA subjects to evaluate the association between carotid intima media thickness and coronary artery calcium score (CACS), as MoSCA and various measures of obesity. Multivariable regression analyses adjusted for traditional cardiovascular risk factors, ethnicity and C-reactive protein were performed. Each unit increase in waist–hip ratio was strongly associated with increase in both common and internal carotid intima media thickness (beta: 0.12, 95% confidence interval (CI): 0.06 to 0.18, p < 0.001 and beta: 0.23, 95% CI: 0.03 to 0.43, p = 0.021, respectively). Measures of central obesity were superior to body mass index as demonstrated by their consistent association with each category of CACS when compared to the reference category (CACS = 0). Compared to body mass index, measures of visceral obesity were significantly associated with MoSCA in this multiethnic healthy population. Waist–hip ratio seems to be more consistent in its association with various MoSCA compared to other anthropometric measures.  相似文献   
74.
Long-term survival and improved neuropsychological function have occurred in selected children with Hurler syndrome (MPS I H) after successful engraftment with genotypically matched sibling bons marrow transplantation (BMT). However, because few children have HLA-identical siblings, the feasibility of unrelated donor (URD) BMT as a vehicle for adoptive enzyme therapy was evaluated in this retrospective study. Forty consecutive children (median, 1.7 years; range, 0.9 to 3.2 years) with MPS I H received high-dose chemotherapy with or without radiation followed by BMT between January 27, 1989 and May 13, 1994. Twenty-five of the 40 patients initially engrafted. An estimated 49% of patients are alive at 2 years, 63% alloengrafted and 37% autoengrafted. The probability of grade II to IV acute graft-versus-host disease (GVHD) was 30%, and the probability of extensive chronic GVHD was 18%. Eleven patients received a second URD BMT because of graft rejection or failure. Of the 20 survivors, 13 children have complete donor engraftment, two children have mixed chimeric grafts, and five children have autologous marrow recovery. The BM cell dose was correlated with both donor engraftment and survival. Thirteen of 27 evaluable patients were engrafted at 1 year following URD BMT. Neither T-lymphocyte depletion (TLD) of the bone marrow nor irradiation appeared to influence the likelihood of engraftment. Ten of 16 patients alive at 1 year who received a BM cell dose greater than or equal to 3.5 x 10(8) cells/kg engrafted, and 62% are estimated to be alive at 3 years. In contrast, only 3 of 11 patients receiving less than 3.5 x 10(8) cells/kg engrafted, and 24% are estimated to be alive at 3 years (P = .05). The mental developmental index (MDI) was assessed before BMT. Both baseline and post-BMT neuropsychological data were available for 11 engrafted survivors. Eight children with a baseline MDI greater than 70 have undergone URD BMT (median age, 1.5 years; range, 1.0 to 2.4 years). Of these, two children have had BMT too recently for developmental follow-up. Of the remaining six, none has shown any decline in age equivalent scores. Four children are acquiring skills at a pace equal to or slightly below their same age peers; two children have shown a plateau in learning or extreme slowing in their learning process. For children with a baseline MDI less than 70 (median age, 2.5 years; range, 0.9 to 2.9 years), post-BMT follow-up indicated that two children have shown deterioration in their developmental skills. The remaining three children are maintaining their skills and are adding to them at a highly variable rate. We conclude that MPS I H patients with a baseline MDI greater than 70 who are engrafted survivors following URD BMT can achieve a favorable long-term outcome and improved cognitive function. Future protocols must address the high risk of graft rejection or failure and the impact of GVHD in this patient population.  相似文献   
75.
OBJECTIVES: This study defined long-term patency of saphenous vein grafts (SVG) and internal mammary artery (IMA) grafts. BACKGROUND: This VA Cooperative Studies Trial defined 10-year SVG patency in 1,074 patients and left IMA patency in 457 patients undergoing coronary artery bypass grafting (CABG). METHODS: Patients underwent cardiac catheterizations at 1 week and 1, 3, 6, and 10 years after CABG. RESULTS: Patency at 10 years was 61% for SVGs compared with 85% for IMA grafts (p < 0.001). If a SVG or IMA graft was patent at 1 week, that graft had a 68% and 88% chance, respectively, of being patent at 10 years. The SVG patency to the left anterior descending artery (LAD) (69%) was better (p < 0.001) than to the right coronary artery (56%), or circumflex (58%). Recipient vessel size was a significant predictor of graft patency, in vessels >2.0 mm in diameter SVG patency was 88% versus 55% in vessels 2.0 mm in diameter.  相似文献   
76.
INTRODUCTION: Long-term glycemic control trials in type 2 diabetes show as the main clinical benefit a difference in retinal photocoagulation (3/1000 in the UK Prospective Diabetes Study [UKPDS]), but no effect on visual acuity or renal failure. No intensive glycemic control trial has yet affected cardiovascular (CV) events, the main cause of morbidity and mortality. By contrast, modest blood pressure reduction has protective effects on visual acuity, renal function, CV events, and mortality. Optimal glycemic control goals are not established in elderly, obese persons with advanced complications, the most common patients in the Veterans Affairs (VA) system. The earlier feasibility trial in such patients (VA-CSDM) suggested potentially worse CV outcomes with lower attained hemoglobin A1c (HbA1c) levels. OBJECTIVES: The primary objective of the Veterans Affairs Diabetes Trial (VADT) is the assessment of the effect of intensive glycemic treatment on CV events. Other objectives are effects on microangiopathy, quality of life, and cost effectiveness. RESEARCH DESIGN AND METHODS: The VADT, started in December 2000, is enrolling 1700 men and women previously uncontrolled on insulin or maximum doses of oral agents at 20 VA medical centers. Accrual is 2 years and follow-up is 5-7 years, with visits every 1.5 months. The study has a power of 86% to detect a 21% relative reduction in major CV events (CV death, myocardial infarction [MI], cerebrovascular accident [CVA], congestive heart failure [CHF], revascularization and amputation for ischemia). Subjects are randomized to an intensive arm aiming at normal HbA1c levels or to a standard arm with usual, improved glycemic control. An HbA1c separation of >1.5% is to be maintained (expected 2%). Both arms receive step therapy: glimepiride or metformin plus rosiglitazone and addition of insulin or other oral agents to achieve goals. Strict control of blood pressure and dyslipidemia, daily aspirin, diet, and education are identical in both arms. Plasma fibrinogen, plasminogen-activating inhibitor I (PAI-I), lipids, renal function parameters, and ECG are measured throughout. Stereo retinal photographs are obtained at entry and 5 years, eye examinations yearly, and intervention as needed to prevent visual deterioration. Recruitment is proceeding on schedule: the current mean HbA1c at entry is 9.4+/-1.6% and mean duration of diagnosed diabetes 11+/-8 years.  相似文献   
77.
Prognostic Factors in Alcoholic Liver Disease   总被引:6,自引:0,他引:6  
Two hundred eighty-one alcoholic patients were prospectively evaluated by clinical, biochemical, and histologic parameters during a 4-yr period to assess their prognosis. They were stratified into four categories of injury: 1) fatty liver (26 patients), 2) acute alcoholic hepatitis (106), 3) cirrhosis (39), and 4) cirrhosis with superimposed alcoholic hepatitis (111). The rate of survival and variables correlating with survival varied according to the group. At 48 months, 70% of the patients with fatty liver were alive, 58% in the alcoholic hepatitis group, 49% in cirrhosis, and 35% in alcoholic hepatitis superimposed upon cirrhosis. Within group one, deaths were due to causes unrelated to liver disease. In the alcoholic hepatitis group, factors significantly correlating with survival were ascites, alanine amino-transferase levels, grams of alcohol consumed, continuation of alcohol intake, and clinical severity of disease. Survival in patients of group three correlated significantly with prothrombin time and histologic severity score. Patients with combined cirrhosis and alcoholic hepatitis exhibited the worst prognosis, with the most significant predictors of survival being age, grams of alcohol consumed, the ratio of serum aminotransferases (AST:ALT) and the histologic and clinical severity of the disease. Although a different pattern of correlates was observed for each pathologic level of injury, knowledge of the various correlates aids in prognostic assessment.  相似文献   
78.
Background and objectives: Health-related quality of life (HRQOL) after acute kidney injury (AKI) is an area of great importance to patients. It was hypothesized that HRQOL after AKI would relate to intensity of dialysis during AKI and dialysis dependence at follow-up.Design, setting, participants, & measurements: The Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network Study was a multicenter, prospective, randomized trial of intensive versus less intensive renal replacement therapy in critically ill patients with AKI. Of 1124 participants, 415 survived at least 60 days and completed the Health Utilities Index (HUI), which measures 8 health attributes and calculates an overall HRQOL score, also called a utility score. How strongly pre–intensive care unit (ICU) health, severity of illness, hospital course, intensity of dialysis, and outcome were associated with 60-day HUI scores was assessed, after adjustment for demographics.Results: The overall HUI score was 0.40 ± 0.37, indicating severely compromised health utility and was associated with only admission from home and hospital and ICU length of stay (LOS). Ambulation was better among those with a shorter hospital and ICU LOS. Better cognition was associated with dialysis independence and with fewer comorbid chronic illnesses. Emotion was associated with only hospital LOS. Pain was associated with ICU LOS.Conclusions: Health utility was low in this cohort of patients after AKI, and intensity of dialysis did not affect subsequent health utility. The effects of a lengthy hospitalization generally outweighed the effects of delayed recovery of kidney function on HRQOL after AKI.A cute kidney injury (AKI) is common among hospitalized patients and is particularly prevalent among patients cared for in the intensive care unit (ICU) setting (13). AKI has been associated with increased morbidity, mortality, and costs (14). It remains unclear to what extent treatment of or recovery from AKI influences health-related quality of life in survivors of AKI. There have been several reports of health-related quality of life (HRQOL) among survivors of AKI in the ICU (510). However, many of these studies are limited by small sample size and low response rate. In addition, follow-up times are variable among and sometimes within studies, ranging from 3 months to several years. Several measures of HRQOL have been used, including the Medical Outcomes Study Short Form 36-item health survey (SF-36) (9), EuroQol (EQ-5D) (5), and Nottingham Health Profile (6,8,10), and also health utilities by time trade-off (7) or visual analog scale (5) and Activities of Daily Living (7,8). Perhaps because of this variability, results are mixed. On balance, limitations in mobility were fairly common, ranging from 29 to 60% (6,8). However, patients generally reported a favorable health status, with 62 to 77% of patients reporting “good” or “excellent” health status (7,10). Health utility on the EQ-5D index was 0.68 compared with an age- and sex-matched norm of 0.86 (5), but in the same study utility by visual analog scale was not different from the general population. Health utility by the time trade-off method was reported by Hamel et al. to be 0.84, but no normative data were presented (7).The availability of HRQOL data in a large cohort of survivors of AKI requiring renal replacement therapy (RRT) provides a unique opportunity to study HRQOL and its potential determinants in this population. The Veterans Affairs/National Institutes of Health (VA/NIH) Acute Renal Failure Trial Network (ATN) study (ClinicalTrials.gov, NCT00076219) was a multicenter randomized trial of intensive versus less intensive renal replacement therapy in critically ill patients with acute kidney injury conducted between November 2003 and July 2007 at 27 VA and university-affiliated medical centers (11,12). Although the major goals of the ATN study were to assess the effects of treatment assignment on 60-day mortality, in-hospital mortality, and recovery of renal function, HRQOL was also assessed at 60 days among survivors with the intention of establishing the effect of dialysis intensity on HRQOL and of assigning health utilities to facilitate performance of cost-effectiveness analysis.We hypothesized that study treatment assignment and ongoing dialysis dependence at 60 days would be potential determinants of HRQOL. Although intensive dialysis did not lead to shorter hospital stays or more rapid recovery of renal function (12), both of which might have contributed to improved HRQOL at 60 days, we postulated that better control of uremia could have direct effects on HRQOL. In addition, given that patients receiving maintenance dialysis routinely report impaired HRQOL (1315), we also hypothesized that ongoing need for dialysis would be an important determinant of HRQOL at 60 days.  相似文献   
79.
CONTEXT: Progestin-only pills, the main hormonal alternative to ethinyl estradiol-containing pills in women bearing vascular risk factors, are poorly tolerated due to irregular bleeding. In contrast, progesterone receptor modulators can inhibit ovulation, alter endometrial receptivity, and improve cycle control. OBJECTIVE: We evaluated the effects of a new progesterone receptor modulator, VA2914, administered continuously for 3 months, on ovulation and endometrial maturation. DESIGN, SETTINGS, AND PATIENTS: Forty-six normal women were included in a prospective, placebo-controlled, randomized trial, conducted in four referral centers. INTERVENTION: VA2914 (2.5, 5, or 10 mg/d) was administered continuously for 84 d. Pelvic ultrasound (treatment d 67 and 77), hormonal monitoring (FSH, LH, estradiol, and progesterone on treatment d 59, 63, 67, 70, 74, 77, 80, and 84), and endometrial biopsy (treatment d 77) were performed. MAIN OUTCOME MEASURE: Ovulation inhibition was assessed by the absence of progesterone values above 3 ng/ml at any time during treatment month 3. RESULTS: Anovulation was observed in 81.8% women in the 5-mg group and 80% in the 10-mg group, and amenorrhea occurred in 81.2 and 90% of cases in the 5- and 10-mg groups. We did not detect any cases of endometrial hyperplasia despite estradiol levels that remained in the physiological follicular phase range throughout treatment cycle 3. CONCLUSIONS: Continuous low-dose VA2914 can induce amenorrhea and inhibit ovulation without down-regulating estradiol levels or inducing endometrial hyperplasia in normal women. Long-term studies with a larger population are required to confirm the contraceptive efficacy of this regimen.  相似文献   
80.
Höglund K  Blennow K 《CNS drugs》2007,21(6):449-462
To date, a number of hypotheses of the cause of Alzheimer's disease, the most common form of dementia, have been postulated. The beta-amyloid peptide (Abeta) is the major constituent of senile plaques, which together with atrophy and neurofibrillary tangles, is the main neuropathological finding in Alzheimer's disease. It is a widely accepted theory that aggregation of Abeta into plaques is an initial event in the pathogenesis of Alzheimer's disease, driving neurodegeneration. The cholesterol hypothesis, primarily based on in vitro and animal studies, states that increased levels of cholesterol promote the production of Abeta. Furthermore, treating animals with HMG-CoA reductase inhibitors ('statins'; cholesterol-lowering agents), or adding these agents to cell culture, results in decreased production of Abeta. This 'positive' effect of statin treatment has further been verified by some, but not all, longitudinal studies where a reduced prevalence of Alzheimer's disease is seen among patients taking statins. These findings have together been interpreted to indicate that statins act via a cholesterol-dependent mechanism, reducing the production of Abeta and, hence, the risk of developing Alzheimer's disease.This review focuses on the cholesterol hypothesis of Alzheimer's disease and investigations into its validity in the clinical setting, i.e. the outcome of clinical trials where the effect of statin treatment on Abeta production has been studied. To date, the cholesterol hypothesis has not been shown to be valid in clinical trials. We hypothesise that the vascular contributions in Alzheimer's disease may be one possible mechanism for statins to interfere with the disease process and reduce the prevalence of Alzheimer's disease. We also suggest that statins may act through the inflammatory pathway. Both of these mechanistic suggestions are good candidates, supported by the literature, for the underlying mechanistic link between statin treatment and a reduced prevalence for Alzheimer's disease.  相似文献   
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