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Biomedical subjects

B Levin

Publications and source records attributed to B Levin.

At least 91 records · Page 5Linked to original sources
PubMed1997

Laryngopharyngeal sensory testing with modified barium swallow as predictors of aspiration pneumonia after stroke.

Improved diagnostic tests that can accurately identify subjects at high risk for aspiration pneumonia (AP) are needed. One measure of this accuracy is the false-negative rate (FNR), which determines the failure of a test to identify a group at high risk. This study compares FNRs for AP among dysphagic stroke patients for two prognostic techniques: modified barium swallow (MBS) alone and MBS combined with laryngopharyngeal sensory discrimination testing (MBS + LPSDT). MBS and LPSDT were performed within 4 weeks of stroke in 20 subjects who were prospectively followed for at least 2 years to identify the frequency of AP. MBS identified 10 patients as not at risk based on the finding of no aspiration on initial MBS; four of these patients developed AP (FNR = 40%). MBS + LPSDT identified five patients as not at risk based on the findings of neither aspiration nor bilateral sensory deficits; none of these patients developed AP (FNR = 0%). The combination of MBS criterion (aspiration) with the LPSDT criterion (bilateral sensory deficits) improves prognostication of outcome in dysphagic stroke patients by identifying a subgroup at high risk for developing AP (nonaspirators with bilateral deficits).

Adult↗
PubMed1997

Early menopause in women with Down's syndrome.

We used the AAMR's Adaptive Behavior Scale to ascertain current menstrual status in a population-based sample of 157 women with Down's syndrome (DS) and 187 women with other intellectual disability, all 40 years of age or older. The age-adjusted likelihood of menopause was twice as high in women with DS syndrome as in women with other intellectual disability (OR = 2.3; 95% CI = 1.1-4.9). Treated thyroid conditions did not influence menstrual status and did not modify the relationship between DS and menstrual status. These findings support the hypothesis that women with DS experience menopause at an earlier age and that this may be associated with accelerated aging.

Adult↗
PubMed1997

Improving care for minority children with asthma: professional education in public health clinics.

OBJECTIVE: Recent studies have shown that lack of continuing primary care for asthma is associated with increased levels of morbidity in low-income minority children. Although effective preventive therapy is available, many African-American and Latino children receive episodic treatment for asthma that does not follow current guidelines for care. To see if access, continuity, and quality of care could be improved in pediatric clinics serving low-income children in New York City, we trained staff in New York City Bureau of Child Health clinics to provide continuing, preventive care for asthma. METHODS: We evaluated the impact of the intervention over a 2-year period in a controlled study of 22 clinics. Training for intervention clinic staff was based on National Asthma Education and Prevention Program guidelines for the diagnosis and management of asthma, and included screening to identify new cases and health education to improve family management. The intervention included strong administrative support by the Bureau of Child Health to promote staff behavior change. We hypothesized that after the intervention, clinics that received the intervention would, compared with control clinics, have increased numbers of children with asthma receiving continuing care in the clinics and increased staff use of new pharmacologic and educational treatment methods. RESULTS: In both the first and second follow-up years, the intervention clinics had greater positive changes than control clinics on measures of access, continuity, and quality of care. For second year follow-up data these include: for access, greater rate of new asthma patients (40/1000 vs 16/1000; P < .01); for continuity, greater percentage of asthma patients returning for treatment 2 years in a row (42% vs 12%; P < .001) and greater annual frequency of scheduled visits for asthma per patient (1.85 vs .88; P < .001); and for quality, greater percentage of patients receiving inhaled beta agonists (52% vs 15%; P < .001) and inhaled antiinflammatory drugs (25% vs 2%; P < .001), and greater percentages of parents who reported receiving patient education on 12 topics from Bureau of Child Health physicians (71% vs 58%; P < .01) and nurses (61% vs 44%; P < .05). CONCLUSION: We conclude that the intervention substantially increased the Bureau of Child Health staff's ability to identify children with asthma, involve them in continuing care, and provide them with state-of-the-art care for asthma.

Black or African American↗
PubMed1997

Cocaine use during pregnancy: sensitive detection by hair assay.

OBJECTIVES: This paper compares the sensitivity of two tests of cocaine use, interview and urine test, with that of a radioimmunoassay of hair. METHODS: Interviews and hair samples were provided by 397 obstetric patients in one New York City hospital; urine samples were obtained in 377. Of these patients, 241 were receiving prenatal care (were registered) and 156 delivered without prenatal care (were unregistered). The 241 registered patients were derived from 400, comprising all reporting use of cocaine ever ("ever-users"), all reporting use by the father but not themselves ("lifestylers"), and a sample of women who were neither ever-users nor lifestylers. The 156 unregistered patients were derived from 352 women interviewed at delivery, unselected for reported use. RESULTS: Thirty-two percent reported ever using cocaine, 45% of these within 6 months before interview. Urine tests were positive in 20%, hair tests in 59%. The estimated sensitivity of the hair test (92%) was 3.1 times higher than that of the urine test (95% confidence interval [CI] = 2.5, 3.8) and 4 times higher than that of reported use in the past 6 months (95% CI = 3.2, 5.0). CONCLUSIONS: Self-report and urine tests alone miss most of cocaine users during pregnancy. Hair tests greatly improve detection and thus can enhance evaluations of the effects of prenatal cocaine use on fetal and child development.

Cocaine↗
PubMed1997

Community-based rehabilitation programs in five countries.

A hallmark of the current era is the shrinking of the world, which will remain a persistent and aggressive trend well into the 21st century. That is good news for businesses, including home care providers. Providers will be able to more easily learn from other countries how to get the job done better--such as how to most effectively care for people with disabilities.

Canada↗
PubMed1997

Temporal variation in chlorinated hydrocarbons in healthy women.

Chlorinated hydrocarbons may increase breast cancer risk. Most epidemiological studies addressing this possibility have used one biological sample to measure a subject's cumulative exposure to these compounds. Little is known about short-term temporal variation in organochlorines, particularly in individuals with low levels. Thus, the reliability of using one sample to assess blood levels of chlorinated hydrocarbons in an epidemiological study is unknown. To better understand the temporal changes in blood measures among women with nonoccupational exposures to these compounds, we collected two 5-ml blood samples, an average of 2 months apart, from each of 31 nonfasting healthy women, ages 45-81 years. Samples were assayed for 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), polychlorinated biphenyls (PCBs), and trans-nonachlor in blinded, matched pairs. Results were adjusted for estimated total plasma lipids. The correlations between the two blood samples were high for DDE and PCBs (lipid-adjusted, r = 0.96 and r = 0.89, respectively). For trans-nonachlor, the correlation was relatively poor (lipid-adjusted r = 0.57); however, with the removal of one outlier, the correlation improved substantially (lipid-adjusted, r = 0.90). The mean difference between the two blood samples in unadjusted [-0.36 ng/ml, 95% confidence interval (CI), -0.97, 0.24 ng/ml, P = 0.23] and lipid-adjusted (-0.035 microgram/g lipid; 95% CI, -0.124, 0.055; P = 0.44) DDE levels was small. Similarly, there was little change in the mean difference for unadjusted (-0.14 ng/ml; 95% CI, -0.53, 0.25 ng/ml; P = 0.47) and lipid-adjusted (0.006 microgram/g lipid; 95% CI, -0.050, 0.062; P = 0.82) PCB levels. The mean differences in trans-nonachlor levels between the two blood draws were also small: unadjusted (-0.03 ng/ml; 95% CI, -0.07, 0.02 ng/ml; P = 0.20) and lipid-adjusted (-0.003 microgram/g lipid; 95% CI, -0.010, 0.004; P = 0.33). These data suggest that temporal changes in organochlorine levels within a 1 to 3-month period are minimal for noncancer patients and that a single measure for estimating exposure is highly reliable for DDE and PCB. For trans-nonachlor, however, where the correlation between blood draws was lower, three samples would be needed for estimating exposure; if an outlier is removed from our data, however, then we can conclude that only a single measure is sufficient. These data, therefore, offer no clear conclusion for the use of a single measurement for trans-nonachlor.

Aged↗
PubMed1996

A family intervention to delay nursing home placement of patients with Alzheimer disease. A randomized controlled trial.

OBJECTIVE: To determine the long-term effectiveness of comprehensive support and counseling for spouse-caregivers and families in postponing or preventing nursing home placement of patients with Alzheimer disease (AD). DESIGN: Randomized controlled intervention study. SETTING: Outpatient research clinic in the New York City metropolitan area. PARTICIPANTS: Referred, volunteer sample of 206 spouse-caregivers of AD patients who enrolled in the study during a 3 1/2-year period. All patients were living at home at baseline and had at least 1 relative living in the area. INTERVENTION: Caregivers in the treatment group were provided with 6 sessions of individual and family counseling within 4 months of enrollment in the study and were required to join support groups. In addition, counselors were available for further counseling at any time. MAIN OUTCOME MEASURE: Time from enrollment of caregivers in the study to placement of the AD patients in a nursing home. RESULTS: Using Kaplan-Meier survival analysis, we estimated that the median time (weighted average of estimates for male and female caregivers) from baseline to nursing home placement of AD patients was 329 days longer in the treatment group than in the control group (z=2.29; P=.02). The relative risk (RR) from a Cox proportional hazard model of nursing home placement (intent-to-treat estimate) after adjusting for caregiver sex, patient age, and patient income was 0.65 (95% confidence interval [CI], 0.45 to 0.94; P=.02), indicating that caregivers were approximately two thirds as likely to place their spouses in nursing homes at any point in time if they were in the treatment group than if they were in the control group. Treatment had the greatest effect on risk of placement for patients who were mildly demented (RR, 0.18; 95% CI, 0.04 to 0.77) or moderately demented (RR, 0.38; 95% CI, 0.17 to 0.82). CONCLUSIONS: A program of counseling and support can substantially increase the time spouse-caregivers are able to care for AD patients at home, particularly during the early to middle stages of dementia when nursing home placement is generally least appropriate.

Aged↗
PubMed1996

Aflatoxin exposure and risk of hepatocellular carcinoma in Taiwan.

To investigate the carcinogenic effect of environmental aflatoxin exposure, 56 cases of hepatocellular carcinoma (HCC) diagnosed between 1991 and 1995 were identified and individually matched by age, sex, residence and date of recruitment to 220 healthy controls from the same large cohort in Taiwan. Blood samples were analyzed for hepatitis B and C viral markers and for aflatoxin-albumin adducts; urine was tested for aflatoxin metabolites. We obtained information about sociodemographic characteristics, habitual alcohol drinking, cigarette smoking and diet in a structured interview. Hepatitis B virus surface antigen (HBsAg) carriers had a significantly increased risk for HCC. After adjustment for HBsAg serostatus, the matched odds ratio (ORm) was significantly elevated for subjects with high levels of urinary aflatoxin metabolites. When stratified into tertiles, a dose-response relationship with HCC was observed. The ORm for detectable aflatoxin-albumin adducts was not significant after adjustment for HBsAg serostatus. HBsAg-seropositive subjects with high aflatoxin exposure had a higher risk than subjects with high aflatoxin exposure only or HBsAg seropositivity only. In male HBsAg-seropositive subjects, adjusted ORs were 2.8 (95% confidence interval [CI] = 0.9-9.1) for detectable compared with non-detectable aflatoxin-albumin adducts and 5.5 (CI = 1.3-23.4) for high compared with low urinary aflatoxin metabolite levels. Our results suggest that environmental aflatoxin exposure may enhance the hepatic carcinogenic potential of hepatitis B virus. A large-scale study will be needed to evaluate the effect of aflatoxin exposure on HBsAg non-carriers.

Aflatoxins↗
PubMed1996

Genetic screening for colorectal cancer and intervention.

There is a complex interaction between environmental/dietary factors and genetics underlying the pathogenesis of colon carcinogenesis. Little data exist concerning the impact of diet on the phenotypic expression of genetically linked colon cancer. As a result, it has been difficult to develop rationally designed dietary intervention studies in first-degree relatives of patients with established familial adenomatous polyposis (FAP), hereditary nonpolyposis colorectal cancer (HNPCC) and other familial colon cancer syndromes. Only 2 double-blinded, placebo-controlled trials have been published concerning the use of preventive strategies in patients with genetically inherited colorectal cancer syndromes, both in patients with FAP. One study evaluated the effects of vitamin C plus vitamin E with or without a high-dose wheat bran fiber supplement on the recurrence of rectal adenomas. Over a 48-month intervention period, only the wheat bran fiber intervention significantly reduced polyp growth. A second study reported that intervention with the NSAID sulindac for 9 months in young patients with FAP resulted in a significant reduction in both polyp number and size in the rectosigmoid colon. All of the large-scale (i.e., >500 randomized participants) phase III nutrient or chemopreventive agent intervention studies thus far have targeted participants with a history of non-familial, sporadic colorectal adenomas. Current clinical adenoma trials do not measure whether the regimen being tested can prevent genotoxic events occurring in early stages of abnormal cell development that contribute to the eventual formation of adenomas nor whether the agent(s) can inhibit events occurring during the progression of adenomas to carcinomas. Therefore, future clinical trial designs may have to consider (i) lengthening the clinical trial period before adenomas develop, (ii) testing at early patient ages and/or (iii) measuring the growth of adenomas as they progress to carcinomas.

Clinical Trials as Topic↗
PubMed1996

Mutation of the hMSH2 gene in two families with hereditary nonpolyposis colorectal cancer.

We examined 18 unrelated individuals who have colorectal cancer or cancers associated with the HNPCC syndrome and have a family history of cancer for mutations in exon 13 of the hMSH2 gene. Two of the 18 individuals had the same previously unreported single-base deletion in codon 705 of hMSH2, resulting in a frame-shift mutation. Two other individuals had a T-to-C base change in the intron sequence at -6 position of the splice acceptor site at the 5' end of exon 13 which has previously been reported to be a polymorphism found in normal individuals (Leach et al., 1993). Nucleotide sequence changes were not detected in the remaining 14 individuals. We examined DNA from additional family members of the two subjects with codon 705 mutations. Of these, two individuals were identified with the mutation who were older than 50 years and who are apparently cancer free. The occurrence of breast cancer in both families (including one individual with a confirmed codon 705 mutation) suggests that breast cancer may be a part of the HNPCC syndrome. This is the first study to describe mutations in the hMSH2 gene in families that do not fit the definition of HNPCC. Because both families with the mutations at codon 705 failed to meet the Amsterdam criteria for HNPCC (Vasen et al., Dis Colon Rectum 34:424-425, 1991), our findings suggest that these criteria should now be reconsidered for purposes of diagnosis of HNPCC.

Adult↗
PubMed1996

Language cortex representation: effects of developmental versus acquired pathology.

Relatively little is known about language cortex representation in patients with developmental pathology and epilepsy. We report the results of mapping language by electrical stimulation of chronically implanted subdural electrodes in 34 patients (mean age, 12.2 years) evaluated for epilepsy surgery, 28 of whom had magnetic resonance imaging or histological evidence of developmental tumors or cortical dysplasia. Language cortex was identified in the temporal or frontal lobe of 19 patients (left hemisphere in 17, right hemisphere in 2), and overlapped or bordered the epileptogenic region in 12. Language cortex was not found in the frontal or temporal lobe of 15 patients (left hemisphere in 4, right hemisphere in 11) and was presumed to be contralateral to grid placement. Three patients with left-hemisphere perinatal or postnatal cerebral insults before the age of 5 years had no language in the left hemisphere, while 3 patients with insults between the ages of 6 and 16 years had preserved left-hemisphere language. Developmental lesions and early-onset seizures do not displace language cortex from prenatally determined sites, whereas lesions acquired before the age of 5 years may cause language to relocate to the opposite hemisphere, but only when language cortex is destroyed.

Adolescent↗
PubMed1996

Cell-specific, multidrug delivery system using streptavidin-protein A fusion protein.

Tissue-specific delivery of variety of molecules has been a valuable technique for biological and medical research and for the diagnosis and therapy of cancer. We have therefore examined the ability of streptavidin-protein A (ST-PA) fusion protein complexed with monoclonal antibodies (mAbs) to transfer biotinylated proteins into specific type of cells. ST-PA/mAbs complexes could efficiently deliver biotinylated beta-galactosidase into a variety of cancer cell lines through molecules expressed on their surface. In addition, ST-PA/mAb complexed with either biotinylated glucose oxidase or biotinylated ribonuclease A could be transferred to specific cell types and made to display cytotoxic activity against the transduced cell. The flexibility of the system was enhanced by the fact that the cell-targeting specificity could be altered by just changing the mAb used and the "payload" molecule could be replaced by substituting one biotinylated protein or enzyme with another. This flexibility was achieved without the need to generate a covalent chemical link or engineering new recombinant molecules. Results obtained to date suggest that the ST-PA fusion protein may be used as a nearly "universal carrier" to transfer a variety of effector molecules into target cells with a high degree of specificity. Essentially, the ST-PA fusion protein effectively serves as a high-efficiency, modular "molecular bridge" for the transfer into cells of a wide variety of effector molecules.

Animals↗
PubMed1996

Age and the ovarian follicle pool assessed with transvaginal ultrasonography.

OBJECTIVE: We tested whether transvaginal ultrasonography could detect the age-related decrease in follicle counts that has been observed in autopsy studies. STUDY DESIGN: Thirty-one healthy volunteers in three age groups (22 to 25, 30 to 33, and 39 to 42 years) underwent ultrasonography in the follicular and luteal phases of the menstrual cycle. At the conclusion of the study the 124 ovarian scans were randomly ordered and antral follicles > or = 2 mm were counted by an evaluator unaware of age. Ordinary least-squares linear regression was used to estimate the associations of age with the total antral follicle count and with ln (1 + follicle count). RESULTS: The numbers of antral follicles > or = 2 mm decreased by about 60% between 22 and 42 years. Age-related decreases were similar for both phases of the cycle and held for both smaller (2 to 3.5 mm) and larger (>3.5 mm) follicles. CONCLUSION: We hypothesize that ultrasonographically derived counts of follicles provide a measure of reproductive age that may help to predict age-related phenomena.

Adult↗