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P Werner

Publications and source records attributed to P Werner.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Interference between a dual-chamber pacemaker and argon electrocautery device during hepatectomy].

We report an unusual electromagnetic interference induced by an argon electrocautery device during a left hepatectomy on a dual chamber pacemaker, implanted for sinus node dysfunction in 87-year-old patient. Argon electrocautery induced inhibition of atrial stimulation and occurrence of irregular ventricular triggered activity. Normal pacemaker function resumed after electrocautery interruption. This case illustrates the need to focus on cardiac rhythm when a new electrical device is used in a pacemaker patient.

Aged↗
PubMed2001

cDNA cloning and physical mapping of porcine 3 beta-hydroxysteroid dehydrogenase/Delta 5-Delta 4 isomerase.

The 3 beta-hydroxysteroid dehydrogenase/Delta 5-Delta 4-isomerase (3 beta-HSD) enzymes are essential for the biosynthesis of steroid hormones. The 3 beta-HSD gene family has been reported to encode for different isoenzymes which function either as dehydrogenase/isomerase or as reductase. The 3 beta-HSD enzymes are involved in the formation of the pheromone androstenone (5 alpha-androst-16-ene-3-one) which contributes to the unpleasant odour present in the meat of uncastrated boars. An reverse-transcription-polymerase chain reaction (RT-PCR) probe from porcine testicular tissue of a 3 beta-HSD enzyme was used to screen a porcine adipose tissue cDNA library. Both strands of the positive clones were sequenced and the putative coding sequence of 1122 nucleotides encodes 374 amino acids. Comparison of the putative open reading frame with the bovine and the human type I homologues revealed 85.6 and 79.3% identity, respectively. Fluorescence in situ hybridization (FISH) was performed with a labelled PAC clone containing the gene of interest. The 3 beta-HSD gene was mapped to the porcine chromosome 4q16-4q21 which is in accordance with the comparative gene map.

Amino Acid Sequence↗
PubMed2001

Nursing staff members' intentions to use physical restraints with older people: testing the theory of reasoned action.

AIM OF THE STUDY: To examine nursing staff members' attitudes, subjective norms, moral obligations and intentions to use physical restraints, using the Theory of Reasoned Action (TRA). RATIONALE: During the last two decades an extensive body of research has examined nurses' attitudes as one of the main factors affecting the decision to use or not to use physical restraints with older persons. However, no studies have examined empirically the antecedents to nurses' intentions to use physical restraints within a theoretically based framework. METHOD: A correlational design was used with 303 nursing staff members from an 800-bed elder care hospital in central Israel. Participants completed a questionnaire including questions based on the TRA as well as socio-demographic and professional characteristics. RESULTS: Regression analyses found attitudes, subjective norms and moral considerations to be significantly associated to intention to use physical restraints with older people. The TRA explained 48% of the variance in nurses' intentions. CONCLUSIONS: The TRA proved to be a useful framework for examining nurses' intentions to use physical restraints. Nurses' attitudes, beliefs and expectations of significant others should be examined before implementing educational programmes regarding the use of physical restraints.

Adult↗
PubMed2001

[Humboldt as mediator: Schleiden and Mohl contra Liebig].

Justus Liebig's book Die organische Chemic in ihrer Anwendung auf Agricultur und Physiologie aroused strong opposition from scientists who felt that they were being attacked. A polarization arose particularly between Hugo von Mohl (1805-1872) and Matthias Jacob Schleiden (1805-1881) on one side, and Justus von Liebig (1803-1873) and his followers on the other side. The debate did not have the character of a purely scientific controversy, however, because social aspects also played a role. Alexander von Humboldt (1769-1859), who held the esteem of both parties, was able to intervene successfully to mediate this conflict. His task appeared at first difficult, but it turned out that both groups had a common enemy, the representatives and followers of the 'Romantic philosophy of nature'. Humboldt, who self-deprecatingly called himself a 'fossil', was forced to recognize that many of his friends and acquaintances, who stood nearer to, or even belonged among the founders of Naturphilosophie, for example, Friedrich Wilhelm Joseph von Schelling (1775-1854) and Johann Bernhard Wilbrand (1779-1846), were also under attack. Although he had earlier been inspired by the concerns and ideas of Schelling's Naturphilosophie, he now distanced himself from them in order to mediate between modern, experimental scientists.

Biological Science Disciplines↗
PubMed2000

Ibuprofen protects dopaminergic neurons against glutamate toxicity in vitro.

Non-steroidal anti-inflammatory drugs (NSAIDs) reduce the risk of Alzheimer's disease, although the underlying mechanisms are unknown. Glutamate excitotoxicity has been implicated in Alzheimer's disease, Parkinson's disease, and others. We examined the effects of aspirin, acetaminophen, and ibuprofen on cultured primary rat embryonic neurons from mesencephalon, the area primarily affected in Parkinson's disease. We evaluated whether these drugs protect dopaminergic neurons against excitotoxicity. All three NSAIDs significantly attenuated the decrease in dopamine uptake caused by glutamate, indicating preservation of neuronal integrity. One hundred micro-moles ibuprofen protected both dopaminergic neurons and neurons overall against glutamate toxicity. In addition, ibuprofen alone increased the relative number of dopaminergic neurons by 47%. Thus, NSAIDs protected neurons against glutamate excitotoxicity in vitro, and deserve further consideration as neuroprotective agents in Parkinson's disease.

Acetaminophen↗
PubMed2000

AIDS myelopathy is not associated with elevated HIV viral load in cerebrospinal fluid.

The pathogenesis of AIDS-associated myelopathy is unknown. Elevated HIV-1 viral load in CSF has been associated with cognitive impairment. The authors investigated if a similar association exists in patients with myelopathy. The authors evaluated levels of HIV-1 RNA in the CSF of 16 individuals with AIDS myelopathy and in 16 nonmyelopathic HIV-infected control subjects. There was no correlation between levels of HIV-1 RNA and the presence or severity of myelopathy.

Acquired Immunodeficiency Syndrome↗
PubMed2000

S-Adenosyl-Methionine improves depression in patients with Parkinson's disease in an open-label clinical trial.

We report a pilot study of S-adenosyl-methionine (SAM) in 13 depressed patients with Parkinson's disease. All patients had been previously treated with other antidepressant agents and had no significant benefit or had intolerable side effects. SAM was administered in doses of 800 to 3600 mg per day for a period of 10 weeks. Eleven patients completed the study, and 10 had at least a 50% improvement on the 17-point Hamilton Depression Scale (HDS). One patient did not improve. Two patients prematurely terminated participation in the study because of increased anxiety. One patient experienced mild nausea, and another two patients developed mild diarrhea, which resolved spontaneously. The mean HDS score before treatment was 27.09 +/- 6.04 (mean +/- standard deviation) and was 9.55 +/- 7.29 after SAM treatment (p < 0.0001). Although uncontrolled and preliminary, this study suggests that SAM is well tolerated and may be a safe and effective alternative to the antidepressant agents currently used in patients with Parkinson's disease.

Aged↗
PubMed2000

Glutamate excitotoxicity--a mechanism for axonal damage and oligodendrocyte death in Multiple Sclerosis?

Glutamate excitotoxicity mediated by the AMPA/kainate-type of glutamate receptors is known not only to damage neurons but also the myelin-producing cell of the central nervous system (CNS), the oligodendrocyte. In Multiple Sclerosis (MS), myelin, oligodendrocytes and axons are lost or damaged as a result of an inflammatory attack on the CNS. Activated immune cells produce glutamate in large quantities by deamidating glutamine via glutaminase. Thus, we hypothesized that during inflammation in MS, glutamate excitotoxicity may contribute to the lesion. This was addressed by treating mice sensitized to develop acute experimental autoimmune encephalomyelitis (EAE) with an AMPA/kainate antagonist, NBQX. Treatment resulted in substantial amelioration of disease, increased oligodendrocyte survival and reduced axonal damage, as indicated by the levels of dephosphorylated neurofilament-H. Despite the clinical differences, NBQX-treatment had no effect on lesion size and did not reduce the degree of CNS inflammation. In addition, NBQX did not alter the proliferative activity of antigen-primed T cells in vitro, further indicating a lack of effect at the level of the immune system. In separate studies, infiltrating immune cells present in perivascular cuffs, commonly the site of entry for invading immune cells, were found to express glutaminase in abundance, supporting the production of glutamate in inflammatory lesions. Thus, glutamate excitotoxicity appears to be an important mechanism in autoimmune demyelination and its prevention with AMPA/kainate antagonists may prove to be an effective therapy for MS.

Animals↗
PubMed2000

Phenylacetylene as a new surrogate standard for the determination of BTEX by GC/FID.

Benzene, toluene, ethylbenzene, xylene (short form: BTEX) and other monoaromatic compounds are environmental contaminants which are often analyzed by GC/FID. For the calculation of BTEX concentrations in water samples normally external quantification with defined BTEX solutions is sufficient. However, for accurate quantification of BTEX in complex matrices it is necessary to use internal standards, e.g. 1-chlorohexane. Isotopes of BTEX are usually the best alternative but they are only applicable to GC/MS, because their retention times are similar to the original BTEX. 1-Chlorohexane and phenylacetylene were compared with respect to their quality as internal standards. Good results were obtained with the monoaromatic phenylacetylene as a surrogate standard. The physical properties of phenylacetylene are very similar to BTEX species and it normally does not occur in environmental samples. 1-Chlorohexane was more strongly adsorbed on the used soil than BTEX during sample preparation. This fact suggests that the single aromatic rings of BTEX and phenylacetylene are mainly responsible for the adsorption behavior.

Acetylene↗
PubMed2000

An integrated linkage-radiation hybrid map of the canine genome.

Purebred dogs are a unique resource for dissecting the molecular basis of simple and complex genetic diseases and traits. As a result of strong selection for physical and behavioral characteristics among the 300 established breeds, modern dogs are characterized by high levels of interbreed variation, complemented by significant intrabreed homogeneity. A high-resolution map of the canine genome is necessary to exploit the mapping power of this unusual resource. We describe here the integration of an expanded canine radiation hybrid map, comprised of 600 markers, with the latest linkage map of 341 markers, to generate a map of 724 markers-the densest map of the canine genome described to date. Through the inclusion of 217 markers on both the linkage and RH maps, the 77 RH groups are reduced to 44 syntenic groups, thus providing comprehensive coverage of most of the canine genome.

Animals↗
PubMed2000

Acetaminophen selectively reduces glioma cell growth and increases radiosensitivity in culture.

Glioblastoma multiforme (GBM) is a highly lethal brain cancer. Using cultures of rodent and human malignant glioma cell lines, we demonstrated that millimolar concentrations of acetylsalicylate, acetaminophen, and ibuprofen all significantly reduce cell numbers after several days of culture. However, their mechanisms of action may vary, as demonstrated by (1) differences in the morphological changes produced by these compounds; (2) varied responses to these drugs with respect to toxicity kinetics; and (3) respective rates of cell proliferation, DNA synthesis, and mitotic index. We studied the effects of acetaminophen on relative cell number further. Evidence is presented that acetaminophen induced cell death by an apoptotic mechanism after a brief burst of mitosis in which cell numbers increased transiently, followed by a reduction in cell number and an increase in DNA fragmentation, as evidenced by terminal deoxytransferase-mediated dUTP-biotin nick end labeling (TUNEL) analysis. Using cultures of adult human brain and embryonic rat brain, we demonstrated that glioma cells were several-fold more sensitive to acetaminophen than normal brain cells in culture. Finally, subtoxic doses of acetaminophen increased the sensitivity of the human glioma cells in culture to ionizing radiation. Taken together, these results suggest that acetaminophen may prove to be a useful therapeutic agent in the treatment of human brain tumors.

Acetaminophen↗
PubMed2000

Glutamate excitotoxicity in a model of multiple sclerosis.

Glutamate excitotoxicity mediated by the AMPA/kainate type of glutamate receptors damages not only neurons but also the myelin-producing cell of the central nervous system, the oligodendrocyte. In multiple sclerosis, myelin, oligodendrocytes and some axons are lost as a result of an inflammatory attack on the central nervous system. Because glutamate is released in large quantities by activated immune cells, we expected that during inflammation in MS, glutamate excitotoxicity might contribute to the lesion. We addressed this by using the AMPA/kainate antagonist NBQX to treat mice sensitized for experimental autoimmune encephalomyelitis, a demyelinating model that mimics many of the clinical and pathologic features of multiple sclerosis. Treatment resulted in substantial amelioration of disease, increased oligodendrocyte survival and reduced dephosphorylation of neurofilament H, an indicator of axonal damage. Despite the clinical differences, treatment with NBQX had no effect on lesion size and did not reduce the degree of central nervous system inflammation. In addition, NBQX did not alter the proliferative activity of antigen-primed T cells in vitro, further indicating a lack of effect on the immune system. Thus, glutamate excitotoxicity seems to be an important mechanism in autoimmune demyelination, and its prevention with AMPA/kainate antagonists may prove to be an effective therapy for multiple sclerosis.

Animals↗
PubMed2000

Relationships between psychotropic drug dosage, plasma drug concentration, and prolactin levels in nursing home residents.

This study aimed to characterize the relationships between administered dosages of psychotropic drugs, plasma drug concentration, and prolactin levels in a group of elderly nursing home residents. In a randomized, placebo-controlled, double-blind crossover design study, blood samples were drawn from 47 nursing home residents at least 6 hours after taking either haloperidol, thioridazine, or lorazepam. Correlations between drug dosage and plasma drug levels were significant for haloperidol and thioridazine, but not for lorazepam. Plasma drug levels were below the levels of detection for most of those taking haloperidol. Lorazepam was detected in the blood of 4 of the participants even after 3 weeks of downward titration to placebo and 6 weeks of placebo. Prolactin level was related to administered dosage only in those who were taking haloperidol. For those taking haloperidol or thioridazine, prolactin levels decreased when participants were on placebo. When an older person is taken off lorazepam, the possibility of residual drug in their bodies even 6 weeks after termination of drug use should be considered. Haloperidol may be clinically active in the brain despite no currently detectable plasma drug concentration.

Aged↗
PubMed2000

Management of osteoporosis: a survey of Israeli physicians' knowledge and attitudes.

BACKGROUND: Osteoporosis is the most common human bone disease. It affects millions of persons throughout the world and its prevalence will increase as the population ages worldwide. OBJECTIVE: To assess Israeli physicians' attitudes and knowledge with regard to management of osteoporosis. METHODS: A questionnaire was mailed to 1,900 Israeli physicians concerning their attitudes to the management of osteoporosis, their prescribing habits, and their knowledge on the pharmacological treatment of the disease. RESULTS: Replies were received from 19% of the physicians. The respondents encouraged physical activity and cessation of smoking for all women, and prescribed estrogen replacement as the main treatment for 50-year-old women. A relatively low level of knowledge was found regarding the adequate dosage of several of the pharmacological treatments. CONCLUSIONS: The findings of the present study stress the need to provide clear guidelines and to extend physicians' knowledge regarding the management of osteoporosis.

Adult↗