PubMed Health⌕ Search

Biomedical subjects

K Kemper

Publications and source records attributed to K Kemper.

At least 19 recordsLinked to original sources
PubMed1999

A spectrophotometric assay for pyrethroid-cleaving enzymes in human serum.

A direct continuous spectrophotometric assay to measure pyrethroid-cleaving enzymes in human serum was developed using cis- and trans-alpha-naphthyl-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate (cis- and trans-naphthyl-Cl2CA). These substrates show a structure very similar to the pyrethroids most often used (e.g. permethrin, cyfluthrin). The method is based on an increase in absorbance at 321 nm which occurs with the hydrolysis of the alpha-naphthyl esters to alpha-naphthol. The assay was optimised regarding type of buffer, pH and substrate concentrations, it was linear for at least 10 min at 37 degrees C. These esterases were completely inhibited by bis-(4-nitrophenylphosphate), a specific carboxyesterase inhibitor. They displayed a great individual variability in human serum, activities were between less than 40 and 1000 U/l for cis-naphthyl-Cl2CA, between less than 40 and 2000 U/l for trans-naphthyl-Cl2CA, respectively. However, a correlation of enzyme activity to sex or age could not be observed. Furthermore, the activity of pyrethroid-cleaving esterases did not correspond to the activities of acylesterase, arylesterase, acetylcholinesterase or butyrylcholinesterase.

Esterases↗
PubMed1997

Animal exposure risks. Implications for occupational health nurses.

1. Diseases transmitted from animals to humans, referred to as zoonoses, pose risks for persons occupationally exposed to animals. 2. Occupational health nurses should be proactive in identifying potential occupational health risks and educating employees to protect themselves from animal exposure risks. 3. Exposure history should include exposure to birds and animals during occupational and recreational activities. 4. Primary prevention is critical, as immunizations and treatments are limited and include many associated risks.

Animals↗
PubMed1995

[Effectiveness of intermittent self-ventilation after ventilator weaning].

The essential cause for long-term mechanical ventilation with unweanability from respirator is chronic failure of the inspiratory muscles. Principally two different causes exist for chronic respiratory failure: Primary pulmonary diseases with overload or load imbalance of primarily uncompromised respiratory muscles, and neuromuscular diseases with a significant decrease in respiratory muscle capacity. Intermittent nocturnal ventilation (INV) leads to recovery by unloading the respiratory pump. In the present retrospective study we examined the value of INV in the "post-weaning-phase" for previously unweanable, long term ventilated patients. In two years (1993 and 1994) 43 patients who had been ventilated for 57.5 +/- 60.3 days in outward intensive care units (ICU) in a predominantly assisted mode we could wean from the respirator within 8.4 +/- 5.5 days by means of consequently applying an individually adapted, volume cycled weaning regime. In all patients, on admission to our ICU and before discharge blood gases, P0.1, Pimax, breathing frequency and tidal volume were measured during spontaneous breathing. After weaning in about 40% of our patients we decided to initiate INV with intermittent positive pressure ventilation (IPPV). The indication for INV after weaning depended on whether a chronic hypercapnic respiratory failure continued to be demonstrable. In this group of patients, INV was the essential stabilizing factor for continuous weaning success, as the respiratory muscles recovered during the ensuing inpatient phase and the daytime PaCO2 normalised. In most of our patients (14 out of 18) INV could be performed non-invasively via breathing masks. Only 4 out of 18 patients continued to be long-term ventilated invasively via tracheostomy. The remaining patients (25 out of 43) showed normoventilation at daytime during the ensuing inpatient phase so they did not need INV. At the time of the patients' referral to our ICU, there was no predictive value regarding the ultimate indication for INV after weaning from respirator.

Adult↗
PubMed1994

The effect of differences in objective and subjective definitions of childhood physical abuse on estimates of its incidence and relationship to psychopathology.

The relationship between objective and subjective definitions of physical abuse and the lifetime prevalence of depression was examined in 280 women attending a family medicine clinic at a large medical center. Based on their responses to a detailed questionnaire regarding discipline and abuse in childhood, 28.2% of these women were objectively defined as abused. Only 11.4% subjectively defined themselves as abused. The proportion of women who experienced depression during their lifetime was highest among those who defined themselves as abused (83%), intermediate among those who met objective criteria for having been physically abused, but did not define themselves as such (56%), and lowest among those who did not meet objective criteria for a history of physical abuse (35%). Similar relationships were found for history of psychotherapy, receipt of psychoactive medication, history of hospitalization for depression, suicide attempts and self-injury.

Adolescent↗
PubMed1989

Jaundice, terminating breast-feeding, and the vulnerable child.

Jaundice is the most commonly treated condition of otherwise well newborns. Although recommended treatments are thought to be safe and effective, the impact of jaundice and therapy on maternal attitudes and behavior is unknown. It was hypothesized that, in contrast to comparison mothers, mothers of jaundiced infants would be more likely to stop breast-feeding in the first month of life, have more separation difficulties with their infant, and be greater users of health care. Both groups of mothers were surveyed in the hospital and 1 month after discharge. Mothers were eligible if their infants were born at Yale-New Haven Hospital after February 1987 and were in the regular nursery. Jaundiced infants had a total serum bilirubin concentration greater than or equal to 205 mmol/L (12 mg/dL); control infants were not jaundiced. Of those who agreed to participate, 84% (85/101) of mothers of jaundiced infants and 80% (124/155) of control mothers completed the 1-month questionnaire. There were no substantial differences between the control and jaundiced groups, respectively, with regard to maternal age (29.1 years vs 29 years) education (66% vs 60% some college), or race (86% vs 82% white). Breast-feeding was more common in the jaundiced group (61% vs 79%, P less than .05). By 1 month, more mothers of jaundiced infants had completely stopped breast-feeding (19% vs 42%, P less than .01). They were more likely to have never left the baby with anyone else (including the father) or left the baby at most one time for less than 1 hour (15% vs 31%, P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Medically unnecessary hospital use in children seropositive for human immunodeficiency virus.

Stimulated by reports that some children who are seropositive for human immunodeficiency virus (HIV+) have been abandoned in the hospital, we studied the extent of, and reasons for, medically unnecessary hospital use at Yale-New Haven (Conn) Hospital among HIV+ children. We reviewed inpatient stays for all HIV+ children hospitalized through Oct 31, 1987. Hospital days were judged to be unnecessary if they failed to meet any of the criteria on the Pediatric Appropriateness Evaluation Protocol. Among 34 children eligible for the study, 54% of their hospital days were judged medically unnecessary; 59% of the children had at least one such day. Unnecessary use was 100% for one-day stays (all for gamma-globulin infusions) and 58% for stays longer than three weeks, with 94% of those unnecessary days being secondary to placement problems. The rate of unnecessary days has declined from 64% of all hospital days in 1983 and 1984 to 30% in 1987 as a result of improved outpatient services and access to foster care. Improved medical and social services could substantially reduce the cost of medically unnecessary hospital care in HIV+ children.

Child↗
PubMed1988

Decreased neonatal serum bilirubin with plain agar: a meta-analysis.

Neonatal jaundice is one of the most common problems leading to prolonged hospitalization of the newborn. Therefore, an effective low-risk, low-cost therapy reducing hospitalization is highly desirable. Plain dried agar, an extract of seaweed, is low cost and low risk; it can bind bilirubin in the gut, decreasing its enterohepatic circulation, thereby decreasing serum levels. Because of conflicting conclusions in the studies of agar's effectiveness in the prevention and treatment of neonatal jaundice, a meta-analysis of their methodologies was done. Criteria for assessing prospective controlled therapeutic trials of agar were established in six areas: hypothesis and clinical outcome, patient selection, treatment group allocation, therapeutic maneuver, use of cotherapies, and data analysis. Nine prospective clinical trials of agar therapy were evaluated using these six criteria. The seven studies with negative conclusions regarding agar's efficacy failed to meet the criteria in several categories: patient selection, therapeutic maneuver, use of cotherapies, or data analysis. All of the studies, including the positive studies, were at risk for biased treatment allocation. Although the pooled data analysis suggests that prophylactic agar treatment is associated with reduced peak serum bilirubin levels, this observation must be interpreted cautiously in light of heterogenous patient populations and the methodologic problems described. Based on this meta-analysis, agar therapy for neonatal jaundice can neither be recommended nor rejected. The methodologic analysis gives clear guidance for future research concerning the effectiveness of agar in treating neonatal jaundice and provides a model for meta-analysis of other prospective trials in pediatrics.

Agar↗
PubMed1986

Direct clean-up and analysis of ribonucleosides in physiological fluids.

We describe the group-selective separation and quantification of unmodified, modified and hypermodified ribonucleosides in physiological fluids (urine, serum) by on-line multidimensional high-performance affinity chromatography (HPAC)-reversed-phase liquid chromatography (RPLC). The excretion levels and patterns of ribonucleosides such as N1-methyladenosine, N1-methylinosine, N2-methylguanosine, N2-dimethylguanosine, N6-carbamoylthreonyladenosine and 2-pyridone-5-carboxamido-N-ribofuranoside were determined in urines from a control group and from patients with different diseases. The HPAC-RPLC method applied represents a powerful tool, e.g. as a non-invasive screening test, a method to investigate disorders in ribonucleoside and/or RNA metabolism, a method for drug monitoring during nucleoside chemotherapy, and a method to study renal ribonucleoside reutilization.

Adolescent↗
PubMed1984

Anorexia nervosa and affective disorders: a controlled family history study.

Analysis of family history information from a prospectively studied group of 40 young female patients with anorexia nervosa and 23 normal control female subjects of similar age showed more depression and substance use disorders in first- and second-degree relatives of anorexia nervosa patients. Further, the pedigrees of the patients differed significantly from those of the control subjects in the higher frequency of depression and substance use disorders in consecutive generations and in the family "loading" of these disorders. These findings, consistent with previous reports, add to the growing evidence of an association between anorexia nervosa and familial risk for affective and related disorders.

Adolescent↗
PubMed1984

Development of a chromatographic method for the quantitative determination of minor ribonucleosides in physiological fluids. Characterization and quantitative determination of minor ribonucleosides in physiological fluids, Part I.

We describe an on-line multi-column high performance liquid chromatographic method for the selective clean-up and analysis of major and minor ribonucleosides in physiological fluids. Quantitative data obtained for the determination of some methylated ribonucleosides in human urines are compared with those obtained with the traditional off-line method. The on-line technique developed in our laboratory is distinguished from the off-line method by the following features: Sample clean-up and analysis of the target-compounds can easily be automatized, Total time of analysis, for example of urinary ribonucleosides, is decreased to 35 minutes, Laborious and error-prone evaporation and redissolution steps are avoided, Reliability of the overall analytical system can be controlled with ease, Small sample-volumes can be applied directly, Sensitive samples can be processed very rapidly under mild conditions, Results obtained with the on-line and off-line-techniques compare well.

Boronic Acids↗
PubMed1983

On-line high-performance liquid affinity chromatography-high-performance liquid chromatography analysis of monomeric ribonucleoside compounds in biological fluids.

We describe an on-line multi-dimensional column chromatography system. It consists of a high-performance liquid affinity chromatography perfractionation column for cis-diol compounds and a series-connected reversed-phase high-performance liquid chromatography system for the analysis of ribonucleosides. This on-line procedure allows the rapid and direct analysis of methylated ribonucleic acid catabolites in biological fluids (serum, urine) and therefore might be useful in pathobiochemistry.

Chemical Phenomena↗
PubMedDate not supplied

A review of 12 commonly used medicinal herbs.

A large and increasing number of patients use medicinal herbs or seek the advice of their physician regarding their use. More than one third of Americans use herbs for health purposes, yet patients (and physicians) often lack accurate information about the safety and efficacy of herbal remedies. Burgeoning interest in medicinal herbs has increased scientific scrutiny of their therapeutic potential and safety, thereby providing physicians with data to help patients make wise decisions about their use. This article provides a review of the data on 12 of the most commonly used herbs in the United States. In addition, we provide practical information and guidelines for the judicious use of medicinal herbs.

Chamomile↗