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991.
We have evaluated four hepatitis E virus (HEV) specific antibody assays, using sequential samples taken from 86 rhesus monkeys at intervals for up to 86 weeks after they had been infected with different doses of HEV. The animals are a common experimental model of hepatitis E. The large collection of sequential samples used avoids uncertainties encountered in previous studies regarding the precise infection status of study subjects and minimizes bias due to the individuality of response to infection. One assay (YES IgG) was produced with synthetic peptides; the others (E2 IgM, E2 IgG, and GL IgG) were produced with recombinant antigens. The results were compared with the viral RNA contents of the serum and stool samples and the occurrence of these virological and immunological markers in the course of the infection was temporally related to the development of hepatitis. Diagnostic utility of the markers was assessed according to their response rates and prevalence at different times in the course of infection. All the animals produced E2 IgG and developed viremia and all but one also produced E2 IgM and excreted the virus in stool, whereas response rates for the other antibodies were lower and decreased with virus dose. Hepatitis occurred over a period of 4 weeks between 3 and 7 weeks after infection. Virological activity occurred mainly during the incubation period and the prevalence of viral markers declined rapidly after the onset of hepatitis. Production of the E2 antibodies immediately preceded the onset of hepatitis, and this was followed about one week later by production of the other antibodies. Seroprevalence E2 IgM reached a peak value 3 weeks after the onset of hepatitis, whereas seroprevalence of GL IgG and YES IgG peaked after the disease had subsided. E2 IgG persisted in all animals for the entire duration of the experiment of up to 86 weeks and possibly beyond and, thus, can serve as a useful epidemiological marker of HEV infection.  相似文献   
992.
The intestinal fatty-acid binding protein-2 (FABP2) gene codes a protein responsible for the absorption of long-chain fatty acids. To test whether FABP2 is a candidate gene for renal disease in patients with type 2 diabetes, a functional A54T polymorphism was genotyped in 1,042 Brazilians with type 2 diabetes. Patients were classified as having normoalbuminuria (urinary albumin excretion [UAE] <20 microg/min; n = 529), microalbuminuria (UAE 20-199 microg/min; n = 217), or proteinuria (UAE >199 microg/min; n = 160). Patients with end-stage renal disease (ESRD) (n = 136) were also included. The prevalence of the TT genotype was higher in patients with renal involvement compared with those with normoalbuminuria (odds ratio [95% CI] 2.4 [1.1-5.4]) following adjustment for type 2 diabetes duration, BMI, hypertension, A1C, and cholesterol levels. The risk was similar considering different stages of renal involvement. In a second independent patient sample (483 type 2 diabetic Caucasians residing in Massachusetts), a significant association was also observed between the TT genotype and proteinuria or ESRD (2.7 [1.0-7.3]; P = 0.048). This study thus provides evidence that FABP2 confers susceptibility to renal disease in type 2 diabetic patients.  相似文献   
993.
Glioblastoma multiforme (GBM) is the most common type of primary malignant brain tumor. Although comprehensive therapeutic measures are available, recurrence is very frequent and the prognosis of GBM remains dismal. To date, little is known about the molecular pathogenesis associated with GBM recurrence. According to Knudson ' s two-hit hypothesis of tumor suppressor gene (TSG) inactivation,1 deletion of a chromosomal region, as revealed by loss of heterozygosity (LOH), is often indicative of the presence of a potential TSG. Allelotype studies involving a comprehensive LOH analysis of the whole genome can provide more detailed and thorough information for detecting genetic anomalies than traditional LOH analysis. The present study is designed to conduct a genome-wide allelotype analysis of one patient ' s primary and corresponding recurrent GBM tumors in an effort to reveal molecular genetic alterations associated with the recurrence of this malignancy.  相似文献   
994.
OBJECTIVE: The aim of this study was to determine the potential clinical utility of tumor markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), and squamous cell carcinoma antigen (SCC-Ag) in patients with FIGO stage IB and IIA squamous cell carcinoma of the uterine cervix with low-risk clinicopathologic factors (negative lymph node metastasis, no lymphovascular space involvement, no bulky tumor size, no parametrial invasion, no deep stromal invasion, and well-differentiated cellular histology). METHODS: A retrospective study was performed on 558 patients with FIGO stage IB-IIA and pathology-proven invasive squamous cell carcinoma of the uterine cervix, treated at the Veterans General Hospital, Taipei, between December 1986 and November 1990. Serum specimens were drawn before operation. A total of 140 assessable patients were enrolled into the study (including 109 stage IB patients and 31 stage IIA patients; all patients had no clinicopathologic risk factors and had at least one tumor marker datum). Survival curves were constructed according to the Kaplan-Meier method and survival curves were compared using the log-rank test. RESULTS: In univariate analysis of survival, CEA, TPA, and SCC-Ag all have roles in the prediction of prognosis. In Cox proportional hazards model using CEA, TPA, and SCC-Ag as covariates, TPA demonstrated the most significant risk factor (P = 0.031). CONCLUSIONS: We concluded that preoperative evaluation of serum TPA might be of great value in the prediction of survival of patients without any clinicopathologic risk factors and this special group of patients should be paid much attention in the follow-up period. From this study, preoperative elevation of TPA defines a group of otherwise low-risk invasive cervical cancer patients who are at high risk for recurrence. Adjuvant therapy might be necessary for this special subset of patients. A prospective study with a larger sample should be conducted to prove this particular finding.  相似文献   
995.
Protein temporal dynamics play a critical role in time-dimensional pathophysiological processes, including the gradual cardiac remodeling that occurs in early-stage heart failure. Methods for quantitative assessments of protein kinetics are lacking, and despite knowledge gained from single-protein studies, integrative views of the coordinated behavior of multiple proteins in cardiac remodeling are scarce. Here, we developed a workflow that integrates deuterium oxide (2H2O) labeling, high-resolution mass spectrometry (MS), and custom computational methods to systematically interrogate in vivo protein turnover. Using this workflow, we characterized the in vivo turnover kinetics of 2,964 proteins in a mouse model of β-adrenergic–induced cardiac remodeling. The data provided a quantitative and longitudinal view of cardiac remodeling at the molecular level, revealing widespread kinetic regulations in calcium signaling, metabolism, proteostasis, and mitochondrial dynamics. We translated the workflow to human studies, creating a reference dataset of 496 plasma protein turnover rates from 4 healthy adults. The approach is applicable to short, minimal label enrichment and can be performed on as little as a single biopsy, thereby overcoming critical obstacles to clinical investigations. The protein turnover quantitation experiments and computational workflow described here should be widely applicable to large-scale biomolecular investigations of human disease mechanisms with a temporal perspective.  相似文献   
996.
We analyzed the wound infection rate of 1,367 primary total hip and knee arthroplasties performed between 1991 and 1999. Two hundred and fifteen arthroplasties were performed with 3 doses (3 x 750 mg) of cefuroxime, and 1,152 arthroplasties were performed with a single preoperative dose (1 x 1 g) of cefazolin as antimicrobial prophylaxis. All wound infections that occurred within 2 years of the index surgery were analyzed. The deep wound infection rate of total hip arthroplasty was 1.1% (95% confidence interval [CI], 0%-3.3%) in the cefuroxime group and 1.1% (95% CI, 0%-2.2%) in the cefazolin group (Fisher's exact test, P = 1.0). The deep wound infection rate of total knee arthroplasty in the cefuroxime group (1.6%; 95% CI, 0%-3.8%) was not significantly different from the cefazolin group (1.0%; 95% CI, 0.3%-1.7%) (Fisher's exact test, P =.63). We concluded that a single dose (1 g) of cefazolin given at anesthetic induction offered similar protection to 3 doses (3 x 750 mg) of cefuroxime in preventing infection in primary total joint arthroplasty.  相似文献   
997.
Little is known about the etiology of adenocarcinoma of the distal esophagus/cardia, a cancer which has increased in incidence in the United States over the last two decades. We analyzed data on smoking, alcohol use, dietary intake, and other factors obtained from 173 hospitalized males with adenocarcinoma of the distal esophagus/cardia (cases) and 4,544 hospitalized males with diseases not related to smoking and of other organ systems than the gastrointestinal tract (controls). Cases of squamous cell carcinoma of the esophagus (n=136) and adenocarcinoma of the distal stomach (n=122) were included as separate case groups. All subjects were interviewed in 28 hospitals in eight cities in the US between 1981 and 1990. After adjustment for covariates, the odds ratio (OR) for adenocarcinoma of the distal esophagus/cardia for current smokers was 2.3 (95 percent confidence interval [CI]=1.4–3.9) and that for ex-smokers was 1.9 (CI=1.2–3.0) relative to never-smokers. The OR for drinkers of four or more ounces of whiskey-equivalents of alcohol per day (relative to those consuming less than one drink per week) was 2.3 (CI=1.3–4.3). Intakes of total fat and vitamin A from animal sources were significant risk factors and fiber intake was associated inversely with adenocarcinoma of the distal esophagus/cardia. Although the number of female cases of adenocarcinoma of the distal esophagus/cardia was small (n=21), significant associations were observed for smoking and alcohol.Dr Kabat is in the Department of Epidemiology and Social Medicine, Albert Einstein College of Medicine, Bronx, NY, USA. At the time of this work be was with the Division of Epidemiology, American Health Foundation, New York, NY. Drs Ng and Wynder are with the Division of Epidemiology, American Health Foundation. Address correspondence to Dr Kabat, Department of Epidemiology and Social Medicine, Albert Einstein College of Medicine, Belfer Bldg, Rm 1302, 1300 Morris Park Avenue, Bronx, NY 10461, USA. Supported by National Cancer Institute Program Project grant CA32617 and Center grant CA17613.  相似文献   
998.
Prospective study of community-acquired rotavirus infection.   总被引:1,自引:2,他引:1       下载免费PDF全文
We determined titers of group A rotavirus common antibodies and neutralizing antibodies against serotypes 1 to 4 of prototype human rotavirus (HRV) in cord blood and serum specimens obtained from 38 infants at 4-month intervals from birth until 2 years of age. Nineteen of the infants developed one episode of HRV diarrhea each, and they were matched by age and birth weight with the other 19 infants, who did not develop HRV diarrhea during the follow-up period. We estimated the incidence rate of HRV infection for the two groups of infants combined to be a minimum of 1.34 episodes per infant per year, which is 22 times more common than the occurrence of overt disease caused by the virus in this community. The infection occurred constantly throughout the first 2 years of infancy, whereas all but one of the 19 episodes of overt disease occurred before 12 months of age. Seven of these overt episodes were preceded by at least one episode of subclinical infection earlier, and the other seven were probably due to primary HRV infection. The remaining five episodes occurred before 4 months of age, so that we could not ascertain whether they were due to primary infections because of the presence of maternal antibodies. We showed that levels of HRV antibodies in serum specimens obtained before clinical onset of diarrhea varied widely, and, for most infants in the diarrheal group, levels of these antibodies were similar to those in the serum specimens obtained at the same times from the corresponding age- and birth weight-matched control infants. Nevertheless, the age at which overt disease caused by HRV was most prevalent coincided with the time when the maternal antibodies had declined to low levels but the infants had not yet acquired high titers of these antibodies in their sera.  相似文献   
999.
With the advent of the skin sparing mastectomy, immediate breast reconstruction with placement of the definitive prosthesis at the time of mastectomy is possible. The question remains: does single-stage prosthetic reconstruction result in greater numbers of complications or rates of re-operation, compared to two-stage tissue expander reconstruction? A retrospective cohort study of a single centre?s experience with these techniques was carried out. From 2004 to 2012, 54 cases of immediate breast reconstruction with implant were identified, and 108 cases of immediate breast reconstruction using a tissue expander were identified. Gathered preoperative data included tumour, prior exposure to radiation, preoperative chemotherapy, smoking, and comorbidities. Complication rates, as well as the rate of secondary operations, were examined. There were no significant increased risks in the rate of post-operative complications (p?=?.910, odds ratio?=?0.9) nor in the rate of re-operation (p?=?0.421, odds ratio?=?1.4) associated with the insertion of a definitive prosthesis at the time of skin sparing mastectomy. However, previously radiated breasts experienced a 100% rate of wound complications in our subset of 9 breasts that underwent one stage breast reconstruction with immediate final prosthesis placement. Our study suggests that patients with early stage disease can undergo single stage breast reconstruction without increased risk of complications nor need for secondary operations. While the mean time to completion of the reconstructive process is shortened by 5 months with the single stage technique, implant based breast reconstruction requires careful counseling and patient selection in radiated patients.  相似文献   
1000.
Recurrent ovarian cancer with long-term survival is uncommon and often associated with poor prognosis. We report three cases of patients with advanced ovarian cancer who have achieved long-term disease-free survival following a single prior relapse. Case 1 relapsed with a localized bulky tumor and received a complete surgical resection and chemotherapy. Case 2 had a persistent central pelvic tumor after debulking surgery and second-line chemotherapy, and yet achieved excellent control with concurrent chemoradiation to the true pelvis. Case 3 relapsed with paraaortic lymph node metastasis and probable lung metastasis (subsequently negated by positron emission tomography) and received chemotherapy alone. These three patients have since remained disease-free for 13, 12, and seven years, respectively, since their first relapse. We conclude that select patients can obtain long-term disease-free survival after the first relapse by accurate restaging and aggressive multimodality treatment.  相似文献   
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