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Biomedical subjects

S Heller

Publications and source records attributed to S Heller.

At least 73 records · Page 4Linked to original sources
PubMed1995

Lack of detection of enteroviral RNA or bacterial DNA in magnetic resonance imaging-directed muscle biopsies from twenty children with active untreated juvenile dermatomyositis.

OBJECTIVE: To investigate for the presence of increased titers of circulating antibody to putative infectious agents and for detectable viral RNA or bacterial DNA in children with active recent-onset juvenile dermatomyositis (DM). METHODS: Magnetic resonance imaging-directed muscle biopsies were performed in 20 children with active, untreated, recent-onset juvenile DM and in age-matched children with neurologic disease. Sera were tested for complement-fixing antibody to Coxsackievirus B (CVB), influenza A and B, parainfluenza 1 and 3, Mycoplasma pneumoniae, mumps, respiratory syncytial virus, and Reovirus; and by immunofluorescence for IgG antibody to Toxoplasma gondii cytomegalovirus and IgM antibody to Epstein-Barr virus. Muscle from juvenile DM patients and control children, CD-1 Swiss mice with and without CVB1 infection, and viral stock positive for CVB1-6 were tested using reverse-transcriptase polymerase chain reaction with 5 primer sets, 4 probes (1 Coxsackievirus, 3 Enterovirus), and universal primers for DNA. RESULTS: No increased antibody, viral RNA, or bacterial DNA was present in the juvenile DM patients or the control children. CONCLUSION: Juvenile DM may be triggered by unidentified agent(s) in the genetically susceptible host.

Adolescent↗
PubMed1995

The development and prediction of atopy in high-risk children: follow-up at age seven years in a prospective randomized study of combined maternal and infant food allergen avoidance.

BACKGROUND: The natural history of allergic disease and its potential for prevention merit close examination because of the explosive worldwide increase in the prevalence and morbidity of atopic disorders. This study examines the development of atopy at age 7 years in 165 children in a high-risk cohort, previously reported from birth to age 4 years. METHODS: In this prospective, randomized, controlled study of food allergen avoidance in infancy, the prophylactic-treated group consisted of infants whose mothers avoided cow's milk, egg, and peanut during the last trimester of pregnancy and lactation and who, themselves, avoided cow's milk until age 1 year (casein hydrolysate supplementation before age 1), egg until age 2 years, and peanut and fish until age 3 years. The control group consisted of maternal/infant pairs who followed standard feeding practices. RESULTS: Despite a significant reduction in food allergy and milk sensitization before age 2 years, none of the following differed between the groups at age 7 years: food allergy, atopic dermatitis, allergic rhinitis, asthma, any atopic disease, lung function, food or aeroallergen sensitization, serum IgE level, or presence of nasal eosinophils or nasal basophilic cells. Children with food allergy by 4 years evidenced higher 7-year (current) prevalences of allergic rhinitis and asthma (p < 0.01). Atopic diseases/parameters at age 7 years were shown, by multivariate analysis (p < 0.05), to be associated with several genetic and environmental risk factors (male gender, maternal nonwhite ethnicity and asthma, and household smoking), as well as predictive atopic markers during infancy (elevated serum IgE level; egg, cow's milk, and peanut sensitization; and nasal eosinophils and nasal basophilic cells). CONCLUSIONS: These findings help to: (1) elucidate the natural history of atopic disease in high-risk children; (2) document the progression of allergy from atopic dermatitis, food allergy, and food sensitization to respiratory allergy and aeroallergen sensitization despite food allergy prevention in infancy; (3) identify allergy predictive markers; and (4) expand our appreciation of the interactions of genetic and environmental factors in the development of atopy.

Child↗
PubMed1995

Analysis of function and expression of the chick GPA receptor (GPAR alpha) suggests multiple roles in neuronal development.

Growth promoting activity (GPA) is a chick growth factor with low homology to mammalian ciliary neurotrophic factor (CNTF) (47% sequence identity with rat CNTF) but displays similar biological effects on neuronal development. We have isolated a chick cDNA coding for GPA receptor (GPAR alpha), a GPI-anchored protein that is 70% identical to hCNTFR alpha. Functional analysis revealed that GPAR alpha mediates several biological effects of both GPA and CNTF. Soluble GPAR alpha supports GPA- and CNTF-dependent survival of human TF-1 cells. In sympathetic neurons, GPAR alpha mediates effects of both GPA and CNTF on the expression of vasoactive intestinal peptide (VIP) as shown by the inhibition of GPA- and CNTF-mediated VIP induction upon GPAR alpha antisense RNA expression. These results demonstrate that GPAR alpha is able to mediate effects of two neurokines that are only distantly related. GPAR alpha mRNA expression is largely restricted to the nervous system and was detected in all neurons that have been shown to respond to GPA or CNTF by increased survival or differentiation, i.e. ciliary, sympathetic, sensory dorsal root, motoneurons, retinal ganglion cells and amacrine cells. Interestingly, GPAR alpha mRNA was additionally found in neuronal populations and at developmental periods not known to be influenced by GPA or CNTF, suggesting novel functions for GPAR alpha and its ligands during neurogenesis and neuron differentiation.

Amino Acid Sequence↗
PubMed1995

External quality assessment scheme for haematology in Germany.

Quality control in haematology is performed in Germany for 20 years. Both cell count, haemoglobin measurement and differential count on smear with morphology exercise and probably diagnosis will be demanded by the participants. Until now this quality control is not mandatory, even efforts are done to change this circumstance, given by the main input of diagnostic value due to haematology results. So this regulation will be changed very soon, in order to submit haematological laboratories to governmental control, effected by the BAK (Bundesärztekammer), as already is done in clinical chemistry. For this EQA the participants cannot expected any financial support by any organization, nor public health, nor private assurance. The role of referee laboratories and reference values as well as difficulties for the adequate reference material are discussed. For the differential count other limits have to be established: recognition of pathological blood films is one of the most important point (in sense of morphological exercise) to ensure broad knowledge of "flag interpretation". Since the last year quality control for reticulocyte count and flow cytometry for immune status and leukemia-differentiation has been established.

Germany↗
PubMed1994

Effect of UV-A light on the catalase activity in the vitreous body of calf eyes.

The present paper reports on the effects of UV-A light on the catalase activity of the calf eye vitreous. A total of 26 eyes were irradiated with UV-A light for 3 h and the catalase activity was compared with that of unirradiated eyes. An increase in activity by 33% was shown in the irradiated eyes. The reason for this increase is the induction of radical formation by short-wave light with subsequently intensified catalase formation or release to enable binding of the radicals formed by the cells. The vitreous must therefore be protected from UV-A light.

Animals↗
PubMed1994

Managed care. An opportunity for home care agencies.

It is clear, even in the future of health care reform, that home care is a growing component of the health care industry. For many years, fee for service was the model reimbursement method. Today we are in a changing health care system that requires a greater emphasis on home care cost containment. New methods of reimbursement are a part of the change. Progressive home care agencies see this as an opportunity to become leaders. This approach does not come without certain risks, however. In taking the risks, it is imperative to minimize the chances for problems, obstacles, and compromising the quality of patient care. It requires that the agency develop a strategy, set a course, and then devote the resources necessary to meet these challenges. Resources may mean investing in upgraded information systems, hiring clinical specialists to develop care plans and protocols, or developing in-house case management staff to allow the agency to monitor use and quality. One thing is clear--the old way of doing business, cost-based fee for service, has a limited life span, and agencies need to embrace these changes, not ignore them.

Delivery of Health Care↗
PubMed1994

Availability of related donors for bone marrow transplantation in sickle cell anemia.

PURPOSE: To determine who might qualify for allogeneic bone marrow transplantation (BMT), we reviewed the medical records of all 143 patients with sickle cell anemia under the age of 16 years who were registered at our center. PATIENTS AND METHODS: A total of 135 records were complete and were used to estimate donor availability and disease severity. The mean number of siblings per patient was two, but this number decreased to 0.73 if half-siblings and siblings who had sickle cell anemia were excluded. Probability calculations indicated that a human leukocyte antigen (HLA)-matched sibling donor would be available for only 18% of patients with sickle cell disease. RESULTS: With regard to clinical severity, if only stroke and chronic debilitating pain are considered criteria for bone marrow transplantation, only 16% of sickle cell patients would qualify, but with use of the broader criteria of the National Collaborative Study, 38% of patients would qualify. However, not all parents will consent to have bone marrow transplantation for their child, and only a minority of patients (18%) will have an HLA-matched sibling donor. Thus, as few as 1-2% of the total population of children with sickle cell anemia will ultimately qualify for marrow transplantation. Increasing the number who can undergo transplantation will require increasing the size of the donor pool. CONCLUSIONS: Search for other therapies not based on marrow transplantation should continue. For the majority of patients with sickle cell disease, these nontransplant treatments offer the best chance for enabling patients to achieve greater longevity and a better quality of life.

Adolescent↗
PubMed1993

GPA and CNTF produce similar effects in sympathetic neurones but differ in receptor binding.

The effects of growth promoting activity (GPA) on sympathetic neurone development were investigated in vitro and compared with the effects of ciliary neurotrophic factor (CNTF). GPA interfered with sympathetic neurone proliferation and induced the expression of vasoactive intestinal peptide (VIP) in neurones from 7-day-old (E7) chick embryos. The biological effects observed with saturating levels of GPA are indistinguishable from the effects of CNTF. The effects on VIP expression suggest that GPA may be involved in the specification of sympathetic neurone phenotypes. Whereas half maximal effects are achieved at lower concentrations of GPA than CNTF, GPA competes less efficiently than CNTF for the binding of 125I-labelled CNTF. This suggests similar, but not identical interactions of CNTF and GPA with receptors on chick sympathetic neurones.

Animals↗
PubMed1993

Development of nasal basophilic cells and nasal eosinophils from age 4 months through 4 years in children of atopic parents.

BACKGROUND: The importance of the inflammatory response in allergic disease has warranted investigation of two of the more integral cells in the pathogenesis of allergic rhinitis, namely, nasal basophilic cells (NBCs) and nasal eosinophils (NEs). In the present study the natural history of NBCs and NEs was studied from birth through 4 years of age in infants of atopic parents to better understand their relationship to the development of various atopic disorders. METHODS: During a prospective, randomized, controlled trial of the effect of maternal and infant food avoidance on the development of atopic disorders in 288 infants of atopic parents, NBCs and NEs were determined semiquantitatively on Wright-Geimsa stained nasal mucosal scrapings and related to each other and to various atopic parameters. RESULTS: In these infants who are at high risk NBCs developed in both those becoming atopic and those remaining nonatopic, but they occurred with increased frequency and quantity in those children in whom most allergic disorders and food or inhalant sensitization developed. NEs, rare at 4 months in all infants, increased in atopic children from 1 to 4 years, and remained infrequent and nominal in nonatopic children. Levels of NBCs and NEs (1) correlated with each other strongly, directly, and with increasing magnitude in children from ages 4 months to 4 years and (2) correlated with log serum IgE levels weakly and moderately in children from ages 2 to 4 years. Stepwise linear regression analyses revealed that allergic rhinitis accounted for most of the variance seen in the level of NBCs and NEs during early childhood, reaching 50% by age 4 years. Asthma, atopic dermatitis, food allergy, food and inhalant sensitization, serum IgE level, and IgG beta-lactoglobulin level accounted for a small proportion of the variance in NBCs and NEs from ages 4 months to 4 years. CONCLUSIONS: These findings help to elucidate the natural history of NBCs and NEs in infants at risk for atopic disorders and document the temporal association of these cells with the development of atopic disease, principally allergic rhinitis.

Basophils↗
PubMed1993

Neurologic consequences of hypoglycemia and pathogenic mechanisms involved in diabetic neuropathy.

Although the limitations of human experimental models of hypoglycemia have hampered investigation, it is generally accepted that a reversible deterioration in cognitive function occurs at a plasma glucose concentration of around 3.5 mmol/L, above the glycemic threshold for symptoms. It is unclear whether this threshold varies in those with hypoglycemia unawareness. Repeated severe hypoglycemia may cause chronic impairment although the clinical significance and the contribution of other factors remains unclear. There is increasing evidence that microvascular abnormalities are the major factor in the pathogenesis of peripheral neuropathy. This may be why there is still little experimental support from human clinical studies for the use of aldose reductase inhibitors in its treatment.

Blood Glucose↗
PubMed1992

Bioluminescence-based detection of genetically engineered microorganisms in nonsterile river water.

The luminescence genes of the marine bacterium Vibrio fischeri were cloned into a lac expression vector and introduced into Escherichia coli and Pseudomonas putida. Survival of the cells in river water samples was monitored by light measurements. Whereas E. coli survived in sterilized river water for more than 29 days, it died off in nonsterile river water after 9 to 13 days. The engineered P. putida cells survived in nonsterile river water for more than 137 days. The detection limit for E. coli was 11 cells/ml.

Cell Survival↗
PubMed1992

The effect of captopril on glucoheptonate uptake in experimental renal artery stenosis.

This study attempted to evaluate the role of glucoheptonate (GHA) in captopril renography in an in vivo laboratory investigation in which postcaptopril glucoheptonate uptake was analysed in awake 2KlC hypertensive rats. Clamped kidney uptake in a previous study was greater in the poststenotic kidney than in the normal kidney (P = 0.01) in rats with mild renal artery stenosis. A glucoheptonate renogram protocol was developed for use in rats anaesthetized with sodium pentobarbital. An 123I-hippuran scan was performed to determine the relative renal function, followed by a control 99Tcm-GHA scan. Five minutes after administering captopril, another 99Tcm-GHA scan was performed. Relative renal uptake was determined between 30 and 90 s postinjection. 99Tcm-GHA uptake in the clamped kidney was more than 50% of total uptake in 3/9 of the abnormal rats' control scans. No abnormal rats clamped kidney 99Tcm-GHA uptake was greater than 50% in the postcaptopril scans. Captopril reduced GHA uptake in all nine of the animals with baseline scans. These findings suggest that the laboratory observation of captopril induced paradoxically increased 99Tcm-GHA uptake in renal artery stenosis may not be observed scintirenographically. Moreover, the data support a potential value of glucoheptonate in captopril renography.

Animals↗
PubMed1991

Course of brittle diabetes: 12 year follow up.

OBJECTIVE: To determine the course of brittle diabetes. DESIGN: 12 year follow up of patients identified in 1977-9 as having brittle diabetes; retrospective review of the case notes. SETTING: Nottingham health district. SUBJECTS: 25 brittle diabetic patients were identified in 1979-9; 11 (five men) had three or more admissions with ketoacidosis between June 1977 and 1979 and 14 (eight men) had three or more attendances at the accident and emergency department with hypoglycaemia in 1978. Two controls from our diabetic register were matched to each patient for age, sex, and duration of diabetes. MAIN OUTCOME MEASURES: Frequency of ketoacidosis and severe hypoglycaemia in the 12 years after ascertainment; diabetic control and complications in 1988-90; retrospective attribution of the cause of brittleness. RESULTS: Patients with recurrent ketoacidosis had had a median (range) of 28 (8-67) episodes. One man died of a cerebral tumour but five of the surviving nine patients had not been admitted in the past two years, although diabetic control remained poor (median haemoglobin A1 concentration 14%). Seven patients had pure hypoglycaemic brittleness, and five had also had eight or more admissions with ketoacidosis (mixed brittleness). Two died of uraemia within a year after ascertainment and two others in hypoglycaemic coma seven and 12 years later. Brittle diabetes was in most cases related to a specific situation, usually unhappiness at home or school. CONCLUSIONS: Brittle diabetes is often episodic and almost always related to stressful life circumstances. Once the underlying cause is removed it tends to improve. Recurrent hypoglycaemic brittleness of psychological origin has a poor prognosis.

Adolescent↗
PubMed1991

Facilitated referral to asthma specialist reduces relapses in asthma emergency room visits.

Facilitated asthma-specialist care delivered by allergists was compared to generalist care on the rate of relapse of asthma emergency room (ER) visits and hospitalizations and on asthma control in a prospective, controlled study of San Diego Kaiser Health Plan members with asthma. Subjects with asthma between the ages of 6 and 59 years presenting for acute ER care for asthma were systematically assigned by alternating, consecutively, the day of their ER visit to receive either (1) facilitated referral to an asthma specialist within the allergy department and concomitant comprehensive ongoing asthma care (intervention group, n = 149) or (2) continued outpatient management from generalist physicians (control group, n = 160). The course of their asthma was evaluated blindly during the subsequent 6 months by review of medical records, initial and follow-up questionnaires, and spirometry. Compared to the control group, the intervention group noted (1) a 75% reduction in the number of, and percent of, subjects with asthma awakenings per night (p less than or equal to 0.0001), (2) an almost 50% reduction in asthma ER relapses (p = 0.017) resulting from a reduction in the frequency of multiple relapse (p = 0.005), and (3) a greater use of inhaled corticosteroids (p less than 0.00001) and cromolyn (p = 0.002). Thus, facilitated referral of subjects with asthma to specialists in asthma therapy after acute ER therapy appears to reduce asthma ER relapses and to improve asthma outcome.

Adult↗
PubMed1990

AIDS-related risk behaviors among substance abusers.

Ninety-two substance abusers were surveyed about AIDS-related risk behaviors. The questionnaire administered elicited information on demographics, sexual practices, substance abuse, and risk behaviors involving the use of needles. Results indicated an appropriate base of prevention knowledge and patients' efforts to modify vulnerability to HIV exposure. Nevertheless, patients continue to engage in behaviors resulting in HIV exposure and transmission.

Acquired Immunodeficiency Syndrome↗