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At least 1,063 records · Page 59Linked to original sources
PubMed1998

Determinants of home health visit length: results of a multisite prospective study.

OBJECTIVES: The authors (1) compare visit length across four categories of skilled nursing home health visits which reflect recent changes in home health casemix-AIDS-related, hospice/terminal (HT), intravenous (IV) therapy, and maternal and child health (MCH)-with general adult medical/surgical (MS) visits and (2) identify factors influencing visit length. METHODS: The study sites were 12 nonproprietary Massachusetts home health agencies (HHAs). Staff nurses collected data concurrently on a sample of visits they provided between December 1, 1992 and November 30, 1993. The visits were stratified by agency, time of year, and visit category. The authors used analysis of variance to test for significant differences across visit categories in Home Length of Visit (the number of minutes between when the nurse entered and left the home) (HLOV). The authors used multivariate regression analysis to develop models identifying determinants of HLOV and adjusted R2 to measure the explanatory power of partial models. RESULTS: In univariate analysis, the categories differed significantly from each other in length (P < 0.0001). HT visits were the longest (median visit length = 60, 80, and 59 minutes for HT Only visits, visits in both the HT and AIDS categories (HT/AIDS), and HT/IV visits, respectively). MS visits were the shortest (median = 30 minutes). The remaining categories were intermediate in length (medians = 37 to 50 minutes). Almost half the variability in HLOV was explained by the full multivariate regression model, which includes all independent variables (adjusted R2 = .4486; P < 0.0001). Visit characteristics alone in a partial model explained 18% of the variability in HLOV. Three other variable sub-groups-agency, client characteristics, and nursing workload-each explained about 15% of the variability in HLOV. Nursing activities performed during the visit explained 11%; several of these related to teaching, education, or assessment. CONCLUSIONS: Accurate reimbursement reflecting casemix differences is important to protect the teaching, education, and assessment functions of nurses; measure nurse productivity and allocate caseloads; maintain access to services for clients with greater needs; and avoid creating economic disincentives to the agencies that serve them. Payers formulating prospective payment systems can adjust per visit reimbursement rates to reflect differences in visit length by category and incorporate functional limitations, clinical instability, and case coordination as classification variables. Developers of home health casemix systems can use factor analysis to improve the robustness of multivariate models and include nursing workload in predicting visit length. Home health agencies measuring productivity and caseload across complex client populations can classify visits into three groups-MS; HT; and AIDS, IV, and MCH-or use the regression results to develop more refined predictors of visit length and nursing caseload.

Adult↗
PubMed2003

Generating neural circuits that implement probabilistic reasoning.

We extend the hypothesis that neuronal populations represent and process analog variables in terms of probability density functions (PDFs). Aided by an intermediate representation of the probability density based on orthogonal functions spanning an underlying low-dimensional function space, it is shown how neural circuits may be generated from Bayesian belief networks. The ideas and the formalism of this PDF approach are illustrated and tested with several elementary examples, and in particular through a problem in which model-driven top-down information flow influences the processing of bottom-up sensory input.

Action Potentials↗
PubMed1990

Kinetics and pathogenicity of autoantibodies induced by mercuric chloride in the brown Norway rat.

Repeated low-dose injections of mercuric chloride (HgCl2) in the brown Norway (BN) rat result in polyclonal activation which includes the induction of anti-glomerular basement membrane (GBM) autoantibodies. We examined the kinetics of various autoantibodies produced in vivo, general features of polyclonal activation such as total IgG levels and immune complex formation, and the relationship between organ specific autoimmunity and tissue injury in the kidney and thyroid. The production of immune complexes and autoantibodies to GBM and thyroglobulin was short lived, and the increase in levels of total IgG and antibodies to ssDNA and dsDNA was prolonged; the antibody response to collagen types I and II was intermediate in duration. Autoantibodies induced by HgCl2 caused only mild and variable tissue injury in the kidneys and did not induce abnormalities in the thyroid. These studies demonstrate that immunostimulation by mercury may result in the formation of a range of autoantibodies, with variable kinetics and pathogenicity.

Animals↗
PubMed1990

Control analysis of systems having two steps catalyzed by the same protein molecule in unbranched chains.

The analysis of the control of a metabolic pathway having an enzyme catalyzing two different reactions (or a protein displaying two different activities) has been performed. For such systems although the summation theorems are valid, the flux and concentration connectivity theorems of the metabolic control analysis are not valid. Another general relationship of control analysis is shown to be more widely obeyed and holds in these systems. An exemplary case, where the enzyme catalyzes two irreversible reactions, demonstrates that the level of one internal intermediate is constant, i.e. it does not depend upon the independent variables of the system.

Catalysis↗
PubMed1983

alpha-Thalassaemia in Apulia: biosynthetic studies.

Analysis of haemoglobin chain synthesis was performed in 15 Apulian patients with Hb H disease and in their patients and offspring. The Apulian carriers of Hb H disease show a marked imbalance of alpha and beta chain synthesis (0.39 +/- 0.1) with variable clinical and haematological manifestations. However, we are dealing with an intermediate form similar to that described in Italians from other regions. A significant difference was found between the mean alpha/beta ratio values (0.81 +/- 0.13) of parents and offspring of Hb H patients and those of the normal controls (1.05 +/- 0.09); however, extensive overlapping between these two groups exists. These results have led us to the conclusion that the forms of alpha-thalassaemia found in Apulia are similar to the alpha defects observed in Sicily; in both cases, in fact, haemoglobin chain synthesis was an unreliable test for discriminating between alpha-thalassaemia-1 trait and alpha-thalassaemia-2 trait.

Hemoglobin H↗
PubMed1990

Lornoxicam, indomethacin and placebo: comparison of effects on faecal blood loss and upper gastrointestinal endoscopic appearances in healthy men.

Forty-five healthy men aged 21-34 years took part in a double-blind, parallel-group, placebo-controlled study of the effects of 28 days' treatment with lornoxicam 4 mg twice daily or indomethacin 50 mg twice daily on faecal blood loss and the endoscopic appearances of gastric and duodenal mucosa. After an initial endoscopic examination, subjects received, intravenously, on day 0, autologous erythrocytes labelled with 51Cr. Complete daily faecal collections were then made from days 6-12, 20-26 and 34-40. The drug treatments or placebo were given from days 13-41. Faecal blood loss was calculated from 51Cr-specific activity of blood and faeces. Endoscopy was repeated 4-8 hours after the last dose of medication; mucosal appearance was graded on a 5-point scale. Lornoxicam caused no more adverse events than placebo; indomethacin caused more indigestion and central nervous system effects, and one subject in this group was withdrawn from the study. Median total blood losses during the pre-treatment and the second and fourth weeks of treatment were respectively 3.33, 3.95 and 5.71 ml for lornoxicam, 2.87, 7.04 and 7.75 ml for indomethacin, and 4.55, 3.64 and 4.13 ml for placebo. Differences between treatments were not statistically significant (P = 0.081 for second week of treatment, P = 0.383 for fourth week of treatment; Kruskal-Wallis test). The effect of chlortenoxicam on faecal blood loss in this study was thus intermediate between placebo and indomethacin, but within- and between-subject variability was such that the differences were not statistically significant. Endoscopic findings were normal in most subjects before and after all treatments, but indomethacin was associated with a slightly greater deterioration in endoscopic score and was the only treatment associated with Grade 3 appearance (in a single patient) in post-treatment endoscopy.

Adult↗
PubMed1989

Iodine sensitivity of bacteria isolated from iodinated water systems.

Fourteen bacterial isolates, predominantly Pseudomonas sp., from two water systems disinfected by iodinated anion-exchange resins were studied and compared with an isolate of Pseudomonas aeruginosa from a povidone-iodine solution and four other isolates. Pseudomonas cepacia and P. aeruginosa grown in brain heart infusion were 3 to 5 logs less sensitive to 1 mg/L I2 (pH 7.2, 1 min) when compared with cultures grown in phosphate buffer. Another P. cepacia isolate was the least sensitive culture when grown in brain heart infusion (1 log decrease) but was more sensitive after cultivation in phosphate buffer (5 logs). Isolates from an iodinated potable water system, including P. cepacia, Staphyloccus warneri, and a Bacillus sp., were all less sensitive to iodine than a "resistant" P. aeruginosa and three other isolates when grown in brain heart infusion. A clinical isolate of P. aeruginosa exhibited intermediate sensitivity. The sensitivity of bacteria to iodine is thus highly variable, depending on the organism as well as the growth conditions.

Bacillus↗
PubMed1983

Novel effects of PGF2 alpha on airway function in asthmatic subjects.

The effects of inhaled prostaglandin F2 alpha (PGF2 alpha) have been examined in eight subjects with asthma. Incremental PGF2 alpha aerosol concentrations, ranging from 1 to 5,000 micrograms/ml, were administered at 15-min intervals. Plethysmographic specific airway conductance (sGaw), forced expiratory volume at 1 s (FEV1), and maximum expiratory flow at 50% vital capacity breathing air (Vmax50% air) and 80% He-20% O2 (Vmax50% He-O2) were measured after each dose and compared with saline control values. We observed unexpected triphasic dose-response characteristics, i.e., an initial decline in physiological variables at low concentrations (1-100 micrograms/ml), followed by improvement at intermediate concentrations (100-1,000 micrograms/ml) and a subsequent steep decline at high concentrations (1,000-5,000 micrograms/ml). Improvement in FEV1 and Vmax50% air between 100 and 1,000 micrograms/ml was associated with sGaw increases above control levels in six subjects and a significant fall in density-dependent index (Vmax50% He-O2/Vmax50% air) when compared with values before challenge and at low concentrations. Inhaled atropine (5 mg) improved prechallenge lung function but had no effect on PGF2 alpha dose-response characteristics. Intermediate PGF2 alpha concentrations given as a single dose consistently induced greater FEV1 reductions than the same concentration during graded dose challenges. Our findings are consistent with the demonstration of in vivo airway tachyphylaxis and indicate that airway effects of PGF2 alpha are far more complex than previously reported. Moreover, these novel effects suggest that, in addition to its well-known bronchoconstrictor effects, PGF2 alpha directly or indirectly causes airway relaxation, predominantly in large airways.

Adolescent↗
PubMed1993

A study of hospital admissions over time, using longitudinal latent structure analysis.

The aim was to study patterns of utilization of non-psychiatric admissions over time and factors affecting the utilization. The study cohort includes all individuals born 1934-66, living in one of two Danish municipalities and admitted to a non-psychiatric department at least once in 1977 (n = 2,686). The hospitalizations of the cohort were followed during a 5-year period by means of the Danish National Patient Register. The data were analysed using a longitudinal latent class (LC) model and a longitudinal latent Markov (LM) model. The LC model suggests that among the cases in the cohort there were 4 variants of utilization patterns. The LM model adequately described the sample in only 3 variants or classes. These classes may be interpreted as a small group of "chronically ill" individuals (1.9% of the cohort), a major group of "healthy" individuals, with no, or only a single, random re-admission during the follow-up period (74.4% of the sample), and finally an intermediate group of "high utilizers" (23.7% of the sample). This "chronicity" variable was markedly associated with mental illness, multiple discharge diagnoses from non-psychiatric departments and total utilization of hospitalizations during the follow-up period. Conversely, gender, age and days in hospital per admission were without importance. The study implies that the analysis of patterns of hospital admissions over time can yield important insight into health service utilization and that longitudinal latent structure analyses are powerful statistical tools in this aspect.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1999

Altered beta-cell characteristics in impaired glucose tolerant carriers of a GAA trinucleotide repeat polymorphism in the frataxin gene.

Friedreich's ataxia is associated with GAA trinucleotide repeat expansions in the frataxin gene. In the general population, these trinucleotide expansions are variable in length, and three types of expansions are seen: short, intermediate, and long repeats. Friedreich's ataxia patients are generally homozygous for the long repeats and exhibit diabetes as pronounced comorbidity. Ristow et al. recently reported an association between the intermediate-length normal allele in the frataxin gene and type 2 diabetes. We have investigated in 94 subjects with impaired glucose tolerance (IGT) as to whether the length of the GAA trinucleotide repeat polymorphism in the frataxin gene associates with parameters reflecting beta-cell function. A hyperglycemic clamp at 10 mmol/l glucose for 3 h was used to quantitate beta-cell characteristics. Carriers of one or two intermediate repeat alleles (n = 32) had a 50% higher median first- phase insulin response to glucose than the noncarriers. Furthermore, they needed less time to reach peak insulin. An analysis of the distribution of the various repeat lengths in elderly type 2 diabetic (n = 179) and control subjects (n = 183), with the same age and ethnic background, did not provide evidence for an association of the intermediate-length repeat allele with type 2 diabetes in Dutch Caucasians.

Aged↗
PubMed1985

Evidence of age-related variation in plasma vasopressin of normotensive men.

The influence of age on plasma arginine vasopressin was examined in three groups of healthy men, 25 +/- 1 (n = 12), 40 (n = 23) and 50 years of age (n = 13), respectively. The three groups were comparable in body height, weight, blood pressure, heart rate, serum and urine osmolality, electrolytes and endogenous creatinine clearance. Compared to the 25-year olds, the 50-year old men had more than three times higher basal plasma vasopressin (7.8 +/- 1.4 vs. 2.5 +/- 0.6 ng/l, p less than 0.01), only one-third the plasma renin concentration (0.36 +/- 0.05 vs. 1.10 +/- 0.33 G.U. X 10(-4)/ml, p less than 0.01) and a significantly higher plasma noradrenaline (267 +/- 21 vs. 199 +/- 19 ng/l, p less than 0.05) while plasma adrenaline remained essentially unchanged. The 40-year olds had intermediate plasma vasopressin concentrations (4.2 +/- 0.6 ng/l). Thus, age is a variable with a substantial effect on plasma concentrations of vasopressin in addition to the well-known effect on renin and noradrenaline. Age must be taken into account in further clinical studies on vasopressin.

Adult↗
PubMed1994

The relationship of maximum or intermediate coccidiostat levels to broiler chick water intake.

Two experiments, each consisting of duplicate battery trials, were conducted utilizing day-old broiler chicks for a 21-d experimental period to study the effects of maximum or intermediate levels of several coccidiostats on water consumption and other performance variables. Drug levels given in Experiment 1 were: halofuginone, 2.97 mg/kg; amprolium and ethopabate, .025%; salinomycin, 66 mg/kg; monensin, 121 mg/kg; and lasalocid, 124 mg/kg. In Experiment 2, levels were: amprolium and ethopabate, .02%; salinomycin, 55 mg/kg; monensin, 99 mg/kg; and lasalocid, 110 mg/kg. Both experiments employed unmedicated control groups. Average final body weights, daily feed intake, and feed:body weight were not affected by treatment in either experiment. In Experiment 1, daily water consumption of birds receiving 124 mg/kg lasalocid was elevated significantly (P < .05) over consumption of control birds and those that received halofuginone. Water consumption to body weight and feed ratios were significantly greater for birds fed lasalocid than for any group other than those receiving amprolium. In Experiment 2, daily water intake of groups receiving 110 mg/kg lasalocid was significantly elevated over that of other coccidiostats and controls. This relationship was also present in calculations of water:body weight and water:feed ratios.

Animals↗
PubMed2002

How to search for the role of gene-environment interactions for lipids in humans.

To target the interventions to the requirements of the individuals we need to identify the genes and the alleles which show variations in response pattern. For example, a lipid-lowering diet is effective for most people, but not so for everyone. The search for genetic polymorphisms that affect the response of LDL cholesterol to diet in humans has been disappointing up till now, and is the first hurdle to take. In addition, it should be realized that the phenotype of serum lipid is not only indicated by the blood level, but is multifaceted. A complication of gene-environment interactions is that in the chain of environmental factor, intermediate phenotype, and pathogenetic process we have the possibility of genetic variability at all levels.

Cholesterol, LDL↗
PubMed2003

Hypersensitivity reactions to drugs: evaluation and management.

Most hypersensitivity reactions to drugs occur within several weeks of administration; signs and symptoms are often consistent with known immune-mediated reactions, including anaphylaxis, rashes, fever, cytopenias and vasculitis. The culprit immune mechanisms range from immunoglobulin E antibody to T cells inducing apoptosis of keratinocytes, in the case of bullous exfoliative rashes. Many drugs induce reactions via altered hepatic metabolism, with production of reactive intermediates which induce a common syndrome of rash and fever plus variable types of other signs. Examples of this reactive metabolite syndrome include the rash and fever in HIV-positive patients given sulfamethoxazole and reactions to the aromatic anticonvulsants. With the notable exception of anaphylaxis and severe bullous exfoliative rashes, most immune reactions to drugs are not life-threatening and generally resolve once the drug is discontinued. The key is prevention. Specific immune testing is standardized only for penicillin. If test results are negative, however, the patient can tolerate all beta-lactam antibiotics. Of those patients with a positive penicillin skin test, only 2% develop reactions when given cephalosporins. Sulfa and quinolone antibiotics, and muscle relaxants, also frequently induce reactions. If there is a history of bullous rash, the patient should never again receive sulfa or quinolone, or related drugs. In other cases, a cautious graded challenge or desensitization can be done. Vancomycin, protamine, and radiocontrast media induce non-immune reactions secondary to their irritant effects on vascular endothelium. Narcotic pain medications cause histamine release by binding to a specific receptor on mast cells in sensitive patients. In contrast to true immune reactions, most patients can receive these medications again, if they are pretreated and the drugs are given slowly. Angiotensin-converting enzymes, aspirin, and non-steroidal anti-inflammatory drugs induce adverse reactions by their effect on enzymes. Readministration usually results in repeat symptoms. It is possible to desensitize patients to aspirin. Some patients appear to develop similar adverse symptoms with multiple unrelated drugs. Although these cases present management problems, most patients can complete a therapeutic course of a vital drug, after careful review of the history, immune testing when possible, and graded challenge or desensitization.

Drug Hypersensitivity↗
PubMed1991

On Phlebotomus perniciosus Newstead, 1911 (Diptera, Phlebotomidae) in the Province of Almeria in southeastern Spain.

Several studies of Phlebotomine sandflies in the province of Almería (Southeastern Spain) showed Phlebotomus perniciosus to be the most abundant and wide-ranging number of the genus Phlebotomus. Samples collected during an entire year showed a population curve characterized by two peaks. Morphological examinations of males revealed marked variability to the peneane valves, and the existence od specimens with intermediate features between P. perniciosus and P. longicuspis. Dissections of females detected 24 specimens out of 522 (4.59%) infected with Leishmania sp.

Animals↗
PubMedDate not supplied

[A database for research in public health].

Epidemiological and health system research projects are often delayed due to the difficulties to build validated data basis in personal computers. This papers presents a new computer interactive program for handling numeric data from a given questionnaire to a structured archive. The questionnaire includes the basic variables of the dwelling and of the members of the household. A list of sociodemographic and health variables are selected, although other variables can be easily added, according to special needs. All the intermediate steps regularly needed to construct a data base are included in the package: capture, verification, validation and record linkage. The package is equipped with the basic procedures needed to produce tabulations and basic statistical analysis.

Databases, Factual↗
PubMed1990

Electrophoretic differentiation of two Halipegus (Trematoda: Hemiuridae) congeners in an amphibian population.

The presence of Halipegus eccentricus, which previously had been absent from a study area, was confirmed when marked genetic differences were observed within what had been thought to be a homogenous population of Halipegus occidualis from the buccal region of the green frog, Rana clamitans. Starch gel electrophoresis was used to determine levels of genetic variation in H. occidualis and H. eccentricus. The H. occidualis population had 12% polymorphic loci and average individual heterozygosity of 0.05. Endemism of snail hosts, limited potential for parasite immigration, monoecious adults, and asexual reproduction occurring in the molluscan intermediate host may be factors that minimize the extent of genetic variability in the parasite population.

Animals↗
PubMed1986

Anterior ischemic optic neuropathy in type I diabetes.

Anterior ischemic optic neuropathy (A.I.O.N.) may cause optic disc edema in type-I diabetes. A.I.O.N. affects diabetic patients of all ages. Such optic neuropathy is more likely to become bilateral in diabetics than in the non-diabetic subjects. A 41-year-old diabetic insulin-dependent woman presented A.I.O.N. in RE; 5 years later, the same affection occurred in LE. The clinical course was relatively benign in both eyes, with good functional restitution. The patient was treated by high doses of Sodium Salicylate and Sulfinpyrazone. The pathogenesis of optic disc edema in type-I diabetes is, according to Hayreh (1981), ischemia of different grade in the district of the posterior ciliary arteries: microangiopathy, rheological anomalies and atherosclerotic added lesions produce a variability of clinical pictures of increasing seriousness. Our case has an intermediate position in such a continuous spectrum. The VEP supported the diagnosia of A.I.O.N.

Adult↗