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Biomedical subjects

A Cohen

Publications and source records attributed to A Cohen.

At least 163 records · Page 9Linked to original sources
PubMed2000

Immunologic response to a single dose of tetanus toxoid in older people.

OBJECTIVES: Several studies have demonstrated that a large percentage of older people are inadequately immunized against tetanus. The aim of this study was to assess the immunity against tetanus in a group of individuals aged 69 and older and to examine the immune response to a single dose of tetanus toxoid. DESIGN: A convenience sample of 115 residents of a large retirement home, aged 69 and older, was studied. After a blood sample for anti-tetanus antibody titer, a single dose of tetanus toxoid vaccine was administered. Repeat titers were obtained 6 weeks after the vaccination and analyzed by ELISA assay. Antibody levels equal to or greater than 0.1 IU/mL were considered protective. RESULTS: Sixty-seven of 115 (58.3%) individuals had adequate antibody titers. Those individuals who reported having been vaccinated with tetanus toxoid in the past were more likely to be immunized adequately compared with those who reported having never been vaccinated (66.7% vs 39.3%, P = .02). After vaccination, 34 of 46 (73.9%) individuals with inadequate antibody titers became seropositive. Those who remained seronegative had mean prevaccination antibody titers significantly lower than those who seroconverted. Sixteen of 17 (94.1%) persons who reported having been vaccinated in the past and were found to be seronegative developed adequate antibody titers following vaccination, compared with only nine of 16 (56.2%) who reported never having been vaccinated (P = .04). There was no association between seroconversion rate and age, sex, underlying diseases, and army service. CONCLUSIONS: Most individuals will develop an adequate anti-tetanus antibody titer following administration of a single dose of tetanus vaccine. A history of past immunization is a good predictor of becoming adequately immunized. It is important that physicians follow the current recommendations for adult immunization and initiate campaigns to ensure that the older population is protected against tetanus.

Aged↗
PubMed2000

Morbidity in reflex sympathetic dystrophy.

Reflex sympathetic dystrophy (RSD), an unusual diagnosis in general paediatrics, is well recognised by paediatric rheumatologists. This study reports the presentation and the clinical course of 46 patients (35 female, age range 8-15.2) with RSD. The patients saw professionals from an average of 2.3 specialties (range 1-5). Twenty five (54%) had a history of trauma. Median time to diagnosis was 12 weeks (range 1-130). Many children had multiple investigations and treatments. Once diagnosis was made, treatment followed with physiotherapy and analgesics. Median time to recovery was seven weeks (range 1-140), with 27.5% relapsing. Nine children required assessment by the child and adolescent psychiatry team. This disease, though rare, has significant morbidity and it is therefore important to raise clinicians' awareness of RSD in childhood. Children with the condition may then be recognised and referred for appropriate management earlier, and spared unnecessary investigations and treatments which may exacerbate the condition.

Adolescent↗
PubMed2000

Significant association of atrial vulnerability with atrial septal abnormalities in young patients with ischemic stroke of unknown cause.

BACKGROUND AND PURPOSE: Atrial septal abnormalities have been associated with cryptogenic ischemic stroke in young patients, but the causal link has not yet been established. Paradoxical embolism is considered the most likely mechanism but is rarely proven. It can be hypothesized that, in those patients, paroxysmal atrial arrhythmias, potentially favored by the anatomic abnormalities, can be another cause of thrombus formation and subsequent embolism to the brain. In this study we assessed the relationship between atrial vulnerability, reflecting arrhythmogenic properties of the atria, and atrial septal abnormalities in young patients with cryptogenic ischemic stroke. METHODS: We enrolled 62 consecutive patients aged <55 years who had ischemic stroke of unknown cause and transesophageal echocardiography to assess atrial septal aneurysm (ASA) or patent foramen ovale (PFO) (ie, atrial septal abnormalities). These patients underwent electrophysiological study to measure atrial refractoriness and conduction time defining a vulnerability index (ie, latent atrial vulnerability) and to assess the inducibility of sustained (lasting >60 seconds) atrial fibrillation with the use of programmed atrial stimulation. Actual atrial vulnerability was defined by the presence of both latent vulnerability and inducibility of sustained atrial fibrillation lasting >60 seconds. RESULTS: We found atrial vulnerability in 58% of patients with atrial septal abnormalities and in 25% of patients without (odds ratio=4.1 [95% CI, 1.3 to 12.7; P<0.02]). The difference between patients with and without PFO or between patients with both PFO and ASA and those without were also significant. Patients with inducible sustained atrial fibrillation had more frequent past history of palpitations and syncope than patients without (P<0.02). CONCLUSIONS: Atrial vulnerability is associated with atrial septal abnormalities in patients with cryptogenic stroke. This result raises the question of the potential role of transient atrial arrhythmias in thrombus formation in the presence of PFO or ASA.

Adult↗
PubMed2000

Growth patterns among infants with language deficits: a case-control study.

We compared growth parameters in infants with language delay to those in children with global delay and to typical controls. Thirty infants with expressive language delay and 36 with combined expressive and receptive language delay were compared with 27 infants with general development delay and with 124 controls. Data on weight, height, head circumference, and feeding behavior were obtained from birth up to age 78 weeks, and converted to percentiles. Medical and sociodemographic data were also evaluated. The weight curves in the combined expressive and receptive language delay group were significantly lower than in the comparison groups, but no cases of failure to thrive were noted. Height and head circumference curves in the combined expressive and receptive language delay group were also lower than in the typical controls. Infants with combined expressive and receptive language delay were lighter and shorter than controls. However, none of the parameters were more than two standard deviations below the mean. It is possible that this finding is of constitutional origin.

Body Height↗
PubMed2000

Needs assessment for mentally disordered offenders: measurement of 'ability to benefit' and outcome.

BACKGROUND: The Department of Health defines needs as "the ability to benefit from healthcare interventions". Outcome measurement is an integral component of needs assessment because it underpins 'ability to benefit'. AIMS: To propose a framework for addressing the measurement of outcome in relation to mentally disordered offenders (MDOs). METHOD: Based on a literature search, the paper reviews the definition and measurement of outcome in general mental health care and specifically in relation to MDOs. It analyses the problems of conducting outcome research in relation to MDOs. RESULTS: A framework for outcome measurement in relation to MDOs is presented. Outcome is placed within a broader framework that relates to service evaluation. CONCLUSIONS: Current measurement of outcome in relation to MDOs is inadequate. A comprehensive framework that acknowledges the multi-dimensional nature of outcome is essential. Researchers must be able to justify the dimensions they prioritise.

Humans↗
PubMed2000

The cellular biology of proton-motive force generation by V-ATPases.

The vacuolar H(+)-ATPase (V-ATPase) is one of the most fundamental enzymes in nature. It functions in almost every eukaryotic cell and energizes a wide variety of organelles and membranes. In contrast to F-ATPases, whose primary function in eukaryotic cells is to form ATP at the expense of the proton-motive force, V-ATPases function exclusively as ATP-dependent proton pumps. The proton-motive force generated by V-ATPases in organelles and across plasma membranes of eukaryotic cells is utilized as a driving force for numerous secondary transport processes. The enzyme is also vital for the proper functioning of endosomes and the Golgi apparatus. In contrast to yeast vacuoles, which maintain an internal pH of approximately 5. 5, it is believed that the vacuoles of lemon fruit may have a pH as low as 2. Similarly, some brown and red algae maintain an internal pH as low as 1 in their vacuoles. It was yeast genetics that allowed the identification of the special properties of individual subunits and the discovery of the factors that are involved in V-ATPase biogenesis and assembly. Null mutations in genes encoding V-ATPase subunits of Saccharomyces cerevisiae result in a phenotype that is unable to grow at high pH and is sensitive to high and low metal-ion concentrations. Treatment of these null mutants with ethyl methanesulphonate causes mutations that suppress the V-ATPase null phenotype, and these cells are able to grow at pH 7.5. The suppressor mutants were denoted as svf (Suppressor of V-ATPase Function). The svf mutations are recessive: crossing the svf mutants with their corresponding V-ATPase null mutants resulted in diploid strains that were not able to grow at pH 7.5. A novel gene family in which null mutations cause pleiotropic effects on metal-ion resistance or on the sensitivity and distribution of membrane proteins in different targets was discovered. We termed this gene family VTC (Vacuolar Transporter Chaperon) and discovered four genes in S. cerevisiae that belong to the family. Inactivation of one of them, VTC1, in the background of V-ATPase null mutations resulted in an svf phenotype that was able to grow at pH 7.5. Apparently, Vtc1p is one of a few membrane organizers that determine the relative amounts of different membrane proteins in the various cellular membranes. We utilize the numerous yeast mutants generated in our laboratory to identify the specific organelle whose acidification is vital. The interaction between V-ATPase and the secretory pathway is investigated.

Amino Acid Sequence↗
PubMed2000

Exposure measurement error in time-series studies of air pollution: concepts and consequences.

Misclassification of exposure is a well-recognized inherent limitation of epidemiologic studies of disease and the environment. For many agents of interest, exposures take place over time and in multiple locations; accurately estimating the relevant exposures for an individual participant in epidemiologic studies is often daunting, particularly within the limits set by feasibility, participant burden, and cost. Researchers have taken steps to deal with the consequences of measurement error by limiting the degree of error through a study's design, estimating the degree of error using a nested validation study, and by adjusting for measurement error in statistical analyses. In this paper, we address measurement error in observational studies of air pollution and health. Because measurement error may have substantial implications for interpreting epidemiologic studies on air pollution, particularly the time-series analyses, we developed a systematic conceptual formulation of the problem of measurement error in epidemiologic studies of air pollution and then considered the consequences within this formulation. When possible, we used available relevant data to make simple estimates of measurement error effects. This paper provides an overview of measurement errors in linear regression, distinguishing two extremes of a continuum-Berkson from classical type errors, and the univariate from the multivariate predictor case. We then propose one conceptual framework for the evaluation of measurement errors in the log-linear regression used for time-series studies of particulate air pollution and mortality and identify three main components of error. We present new simple analyses of data on exposures of particulate matter < 10 microm in aerodynamic diameter from the Particle Total Exposure Assessment Methodology Study. Finally, we summarize open questions regarding measurement error and suggest the kind of additional data necessary to address them.

Air Pollution↗
PubMed2000

Long-term value of exercise testing after acute myocardial infarction: influence of thrombolytic therapy.

OBJECTIVES: To evaluate the long-term predictive value of exercise testing performed early after acute myocardial infarction (AMI) in patients receiving thrombolytic therapy. DESIGN: Nonblinded prospective follow-up study. SETTING: Cardiac rehabilitation unit in a 900-bed university hospital. SUBJECTS: Four hundred forty-three patients allowed to perform exercise testing 3 weeks after AMI were followed for a median of 75 months; 183 received IV thrombolysis and 263 did not. RESULTS: Cardiac death hazard ratios were significantly increased in the presence of reduced physical working capacity on exertion, left ventricular dysfunction, and > or = 1-mm (but < 2-mm) ST-segment depression on exertion. In the group receiving thrombolytic therapy, no patient with > or = 2-mm ST-segment depression on exercise died; this group was characterized by a high rate of revascularization, whereas the group with > or = 1-mm but < 2-mm ST-segment depression was not. No parameter related to clinical or exercise testing predicted recurrent infarction in the group receiving thrombolytic therapy. Among patients not receiving thrombolysis, cardiac death was significantly related to > or = 2-mm ST-segment depression on exertion, to reduced physical working capacity, and to the lack of revascularization during follow-up. CONCLUSION: Exercise test-derived parameters have variable value in predicting long-term survival of patients performing exercise test after AMI depending on the following: (1) whether thrombolytic therapy was given or not; (2) the degree of ST-segment depression during exercise testing; and (3) the rate of revascularization.

Adult↗
PubMed2000

Intrapartum maternal fever and neonatal outcome.

OBJECTIVE: Much of fever during term labor may not be infectious but rather a consequence of the use of epidural analgesia. Therefore, we investigated the association of elevated maternal intrapartum temperature with neonatal outcome when the infant does not develop an infection. METHODS: We studied 1218 nulliparous women with singleton, term pregnancies in a vertex presentation and spontaneous labor. Women were excluded if their temperature was >99.5 degrees F at admission for delivery, if they were diabetic or had an active genital herpes infection or if their infant developed a neonatal infection, had a congenital infection, or had a major malformation. Maximum intrapartum temperature was categorized as: </=100.4 degrees F (afebrile), 100.5 degrees F to 101 degrees F, and >101 degrees F. RESULTS: During labor, 123 women (10.1%) developed a fever >100.4 degrees F; 62 (5.1%) women had a maximum temperature of 100.5 degrees F to 101 degrees F and 61 (5.0%) women had a maximum temperature >101 degrees F. Of febrile women, 97.6% had received epidural analgesia for pain relief. Infants of women developing a fever >100.4 degrees F were more likely to have a 1-minute Apgar score <7 (22.8% for >100.4 degrees F vs 8.0% for afebrile) and to be hypotonic after delivery (4.8% for >100.4 degrees F vs.5% for afebrile). Compared with infants of afebrile women, infants whose mothers' maximum temperature was >101 degrees F were more likely to require bag and mask resuscitation (11.5% vs 3.0%) and to be given oxygen therapy in the nursery (8.2% vs 1.3%). We also found a higher rate of neonatal seizure with fever (3.3% vs.2%), but the number of infants with seizure was small (n = 4). All associations remained essentially the same after controlling for confounding in logistic regression analyses. CONCLUSIONS: Intrapartum maternal fever, particularly if >101 degrees F, was associated with a number of apparently transient adverse effects in the newborn. Larger studies are needed to investigate the association of intrapartum fever with neonatal seizures and to determine whether any lasting injury to the fetus may occur.

Adult↗
PubMed2000

Infants with a thumb-in-fist posture.

OBJECTIVE: In early infancy the infant's thumb is not infrequently enclosed within the palm, ie, thumb-in-fist (TIF). This posture has received scant attention in the neurodevelopmental literature. Its prevalence, resolution, and clinical associations were investigated in this study. METHODOLOGY: Two hundred sequentially born, apparently healthy full-term newborn infants comprised the cohort. The whole study group was followed up until the disappearance of the TIF occurred. In the first 150 of the cohort, additional data on development and the neurological status were obtained at 12 months of life. RESULTS: In 125 infants (62.5%) of the total cohort, a TIF was noted. The mean age of disappearance was 1.5 months, and no TIF persisted after 7 months old. No relationship was noted between the TIF resolution and abnormal neurological signs or gross or fine motor development. The only association noted between age of resolution of the TIF and the neurodevelopmental status was a delay in language attainment at the 12-month screening. CONCLUSIONS: The TIF posture in infancy was noted in 65% of our cohort, and it had resolved in all infants by 7 months old. Therefore, a TIF posture after this age should alert the clinician to the possibility of possible neurological dysfunction. An unanticipated association of a delay in the 12-month language milestone attainment was noted in those infants with later resolution of the TIF posture. No data on language development in this group were obtained after 12 months old; therefore, the clinical significance of this finding is not yet elucidated.

Cohort Studies↗
PubMed2000

Intrapartum fever and unexplained seizures in term infants.

OBJECTIVE: Early-onset neonatal seizures are a strong predictor of later morbidity and mortality in term infants. Although an association of noninfectious intrapartum fever with neonatal seizures in term infants has been reported, it was based on only a small number of neonates with seizures. We therefore conducted a case control study to investigate this association further. METHODS: All term infants with neonatal seizures born at Brigham and Women's Hospital between 1989 and 1996 were identified. For this study, cases consisted of all term neonates with a confirmed diagnosis of seizure born after a trial of labor for whom no proximal cause of seizure could be identified. Infants with sepsis or meningitis were excluded. Four controls matched by parity and date of birth were identified for each case. The rate of intrapartum maternal temperature >100.4 degrees F was compared for case infants and controls. Potential confounding was controlled in logistic regression analysis. RESULTS: Cases comprised 38 term infants with unexplained seizures after a trial of labor. We identified 152 controls. Infants with seizures were more likely to be born to mothers who were febrile during labor (31.6% vs 9.2%). In almost all cases, the fever developed during labor (94.7% cases, 97.4% controls). At admission, mothers of infants with seizures were not significantly more likely to have factors associated with concern about infection such as a white blood cell count >15 000/mm(3) (28. 9% vs 19.1%) and premature rupture of the membranes (15.8% vs 17.8%). In a logistic regression analysis controlling for confounding factors, intrapartum fever was associated with a 3.4-fold increase in the risk of unexplained neonatal seizures (odds ratio = 3.4, 95% confidence interval = 1.03-10.9). CONCLUSION: Our data indicate that intrapartum fever, even when unlikely to be caused by infection, is associated with a fourfold increase in the risk of unexplained, early-onset seizures in term infants.

Adult↗
PubMed2000

Paclitaxel, 5-fluorouracil, and leucovorin (TFL) in the treatment of metastatic breast cancer.

To assess the activity of paclitaxel in combination with 5-fluorouracil (5-FU) and leucovorin in breast cancer, a phase II trial was conducted in women with metastatic disease. Toxicity, response rate, median survival, median duration of response, and median time to disease progression were measured. Between January 1994 and May 1996, 47 patients with metastatic breast cancer and an Eastern Cooperative Oncology Group (ECOG) performance status (PS) < or = 2 who had previously been treated with chemotherapy received 175 mg/m2 paclitaxel over 3 hours on day 1. After paclitaxel administration, 300 mg intravenous (i.v.) leucovorin over 30 minutes was administered followed by 350 mg/m2 i.v. push 5-FU. Both 5-FU and leucovorin were given on days 1-3. Treatment was repeated every 28 days for a minimum of 6 cycles per patient. Two (4%) patients had a complete response and 21 (45%) patients had a partial response for an overall response rate of 49% (95% confidence interval: 35%-63%). The median survival was 17.7 months, median duration of response was 8.6 months, and median time to disease progression was 6.3 months. There was no statistical difference in survival or time to progression between anthracycline-naive, anthracycline-sensitive, and anthracycline-resistant patients. Nine (19%) patients had grade 3 or 4 neutropenia, and no patient required blood or platelet transfusion. The most frequently observed nonhematologic toxicities were arthralgia and myalgia. Pharmacokinetic data were obtained on 19 patients. Responders had higher peak plasma concentrations of paclitaxel than nonresponders (4.46 vs. 2.9 micrograms/mL; P = 0.02). Paclitaxel/5-fluorouracil/leucovorin is an active, well-tolerated regimen for patients with metastatic breast cancer.

Adult↗
PubMed2000

The effect of a 'fast-track' unit on the performance of a cardiothoracic department.

OBJECTIVE: The objective of this study was to describe the impact of a 'fast-track' unit, combined with a computerised system for information collection and analysis, on the clinical practice and finance of a cardiothoracic department over the first 12 month period of its application. METHODS: Within 12 months, starting December 1996, 642 major cardiothoracic cases were performed at the Cardiothoracic Department, St Mary's Hospital, London, after the establishment of a 3-bed 'fast-track' unit, which was supported by a computerised system for admission planning and a pre-admission clinic. The main outcome measures were operating numbers, financial income, patient recovery and operative mortality. RESULTS: The 'fast-track' unit resulted in an increase of the operating numbers (11.3% increase in major cardiac cases) and income (38%), as compared with the year before. Some 525 patients out of 642 (81.8%) were scheduled for the 'fast-track' unit and 492 (93.7%) were successfully 'fast-tracked'. Coronary artery bypass grafting operations had the lowest 'fast-track' failure and mortality rates. Re-do operations and complex coronary procedures presented a high 'fast-track' failure rate of approximately 20-25%. Low cardiac output, postoperative bleeding and respiratory problems were the most frequent causes for 'fast-track' failure. CONCLUSIONS: The development of a 'fast-track' unit, supported by a computerised system for information collection and analysis and a pre-admission clinic, has resulted in a substantial improvement of operating numbers and financial income, without adversely affecting the clinical results. This task demanded close collaboration between a dedicated list manager and a designated member of the medical team. Patient selection with appropriate 'fast-track,' criteria may improve further the efficiency of 'fast-track' units in the future.

Aged↗
PubMed2000

Chronic relapsing thrombocytopenic purpura with severe neurological manifestations and full recovery.

Neurological complications in thrombotic thrombocytopenic purpura (TTP) are associated with poor prognosis and/or permanent damage. We report a young woman in whom the diagnosis of TTP was difficult because cardinal manifestations were absent at presentation. The patient relapsed, showing severe and dramatic neurological manifestations, including coma. She was treated with multiple therapeutic modalities and recovered fully with no neurological sequelae. The difficulties involved in the management of chronic relapsing TTP are discussed. In the absence of clear guidelines, patients are still subjected to different treatment modalities according to the personal opinions and approaches of physicians. Clearly, well-controlled clinical trials to address this problem are required.

Adult↗
PubMed2000

Gender differences in the reactogenicity of measles-mumps-rubella vaccine.

BACKGROUND: In trials comparing different formulations of measles vaccine, excess non-specific mortality occurred in female children who received high titer vaccine. These findings suggest a gender-specific effect of measles vaccine. OBJECTIVES: To determine whether gender differences exist in the rates of adverse reactions and morbidity in the month following immunization with measles-containing vaccine, and to evaluate whether there is a gender-specific association between the humoral immune response to measles vaccination and post-vaccination morbidity. METHODS: Parents completed questionnaires on the health status of 755 infants aged 15-20 months, during the month preceding and the month following the measles-mumps-rubella vaccination. Blood samples were tested for measles antibody titers in a subsample of 237 infants. RESULTS: After controlling background morbidity in the infants, the relative risk of fever and rash following vaccination was 2.35 in females and 1.36 in males. The geometric mean antibody titers against measles were similar in both sexes and there was no significant association between antibody titer and post-vaccination morbidity in either sex. CONCLUSIONS: Our findings demonstrate higher rates of adverse effects in females following vaccination with MMR vaccine, irrespective of the humoral response. This study emphasizes the need to consider possible gender differences when evaluating new vaccines.

Antibodies, Viral↗
PubMed2000

Nutrition and quality of life in the aged: the Jerusalem 70-year olds longitudinal study.

Inadequate nutrition is a major problem of elderly people today. Yet, despite the prevalence and significance of the problem, there is little information on the nutritional status of elderly persons in the community, and its impact on their quality of life. During 1990-1991, as part of a first cross-section in a longitudinal medical and social study of 70-year olds in Jerusalem, we surveyed the nutritional status of this population. During the first phase, 605 people were examined in their homes; data were collected regarding socioeconomic status, education, self-perceived health state, use of medications and health services, and ADL. During the second stage, a sub-group of 463 people was examined in a geriatric outpatient clinic; all subjects underwent medical history, physical examination, cognitive assessment, psychiatric questionnaire, blood and urine tests, electrocardiogram, and pulmonary function tests. In addition, general hospital admissions and morbidity and mortality in the two years following the study were studied. The nutritional status of the participants was determined according to nutritional assessment (NA) scale, based on the Mini Nutritional Assessment (MNA). The majority of the study population lived at home, was without cognitive disturbance (86%), and was independent in ADL (83%). Based on NA > 24, 91% of the study population were in good nutritional state, 8.3% were at risk of undernutrition, and 0.7% were malnourished. There was a significant positive relationship between NA score and ADL as well as cognitive state. In addition, a strong negative relation was found between NA score and visits to the family physician in the previous fortnight, visits to the emergency room in the previous year, and hospital admissions in the following two years. An inverse relation, although not significant, was found between NA score and two-year post-study mortality. These results suggest that the nutritional status of the studied population is inadequate, and that the nutritional state is one of the major determinants of the quality of life in the elderly and therefore, should be part of any geriatric assessment. Elder population surveys are needed to identify and treat at risk elders.

Aged↗