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W Baier

Publications and source records attributed to W Baier.

At least 19 recordsLinked to original sources
PubMed1995

Relative roles of natural killer- and T cell-mediated anti-leukemia effects in chronic myelogenous leukemia patients treated with interferon-alpha.

Potential anti-leukemia effects mediated by T cells or by natural killer (NK) cells were investigated in chronic myelogenous leukemia (CML) patients treated with interferon-alpha. Therapy-associated modulation of T cell and NK reactivity was monitored for one year from initiation in autologous mixed lymphocyte-tumor cell reactions and cytotoxicity directed against autologous CML cells, respectively. During the course of IFN-therapy, NK activity against autologous CML cells increased steadily, whereas T cell reactivity fluctuated randomly. Despite the high level of T cell reactivity to autologous tumor cells in short-term (6 days) culture, 1) they failed to respond to synthetic peptides corresponding to the bcr/abl fusion sequence of the patient, and 2) only one proliferative T cell clone (TCC) was isolated which specifically recognized HLA-DR-matched CML cells. This TCC appeared not to recognize synthetic peptides corresponding to the bcr/abl fusion sequence of the patient; the antigen to which it responds remains unknown. To assess potential immunogenicity of bcr/abl peptides, it was attempted to sensitize T cells from normal donors in vitro. Of 109 cell lines obtained from seven different donors, eleven showed peptide-dependent proliferation. Therefore, although these results show that it is possible to isolate apparently CML-specific T cells from patients, as well as to prime T cells against tumor-specific peptide in vitro, the frequency of such T cell-mediated reactivity appears low and its relevance to anti-leukemic effects questionable. On the other hand, the strong time-dependent enhancement of natural killing of autologous CML blasts during IFN-alpha treatment, a phenomenon not observed for T cell reactivity, suggests that natural immunity may be more important in controlling disease.

Amino Acid Sequence↗
PubMed1994

Controlled trial of backrest elevation after coronary angiography.

BACKGROUND: Protocol at most centers requires keeping the head of the bed flat for at least 5.5 hours after coronary angiography. OBJECTIVE: To determine the effect of head of bed elevation after diagnostic coronary angiography on patient comfort and on the incidence and timing of postprocedural complications. METHODS: A convenience sample of 120 adult patients on the short-stay special procedures nursing unit of a university teaching hospital was used. Patients who had undergone elective diagnostic coronary angiography via the femoral artery were randomly assigned to a control or experimental group. The control group had the head of bed maintained at 15 degrees or less for 5.5 hours after the procedure. The experimental group had the head of bed gradually elevated from 15 degrees to 60 degrees over the 5.5 hours. Both groups dangled and ambulated after 5.5 hours. All other aspects of the procedure were identical. Outcome was measured by incidence and timing of dizziness, hypotension, bleeding, hematoma, and diminished foot pulses. Level of pain was assessed on a scale of 0 to 10. RESULTS: No statistically significant differences were noted between groups in the incidence of complications. The incidence of back pain at a level of more than 3 on a scale of 0 to 10 was less for the experimental group than for the control group. CONCLUSIONS: Elevation of the head of the bed after coronary angiography decreases discomfort with no increase in complications. Replication of this study is needed for verification.

Beds↗
PubMed1992

Association of Kawasaki disease and interstitial nephritis.

Renal insufficiency is a rare manifestation of Kawasaki disease. We report a 2.5-year-old boy with Kawasaki disease who developed acute renal failure during the acute phase of his illness. A percutaneous renal biopsy revealed acute interstitial nephritis. No etiological agent could be identified and renal recovery occurred with supportive care alone.

Acute Kidney Injury↗
PubMed1992

Insulin-like growth factors decrease oxygen-regulated erythropoietin production by human hepatoma cells (Hep G2).

We examined the effects of insulin-like growth factors (IGFs) and insulin on erythropoietin (EPO) production by human hepatoma cells (Hep G2). Compared with normoxia (20% O2), EPO production by Hep G2 cells during a 72-h incubation was stimulated fivefold by exposure to low oxygen tension (1% O2) and nearly threefold by exposure to cobalt chloride (100 microM). IGF-I caused a concentration-dependent attenuation of EPO formation under normoxic conditions and inhibited (maximally 50%) EPO production stimulated by either low oxygen tension or cobalt [half-maximal effect (ED50) approximately 5 nM]. The increase of EPO mRNA levels in response to hypoxia was significantly reduced by IGF-I. Similarly to IGF-I, IGF-II (ED50 approximately 8 nM) and insulin (ED50 approximately 80 nM) also inhibited EPO formation in Hep G2 cells. IGF-I (100 pM-100 nM) stimulated the incorporation of radiolabeled alanine as a measure for total protein synthesis, 3H-labeled thymidine incorporation into DNA, and glycogen synthesis at 20 and 1% O2 in a concentration-dependent fashion. IGF-I exhibited a high affinity for the IGF-I receptor (apparent Kd approximately 3 nM). Unlabeled insulin was greater than 100-fold less potent than IGF-I in competing for 125I-IGF-I binding (apparent Kd approximately 360 nM). Conversely, insulin bound to the insulin receptor with high affinity (apparent Kd approximately 0.3 nM), whereas IGF-I was less than 1% as potent in competing for 125I-insulin binding. In summary, IGFs and insulin exert a negative control function on oxygen-regulated EPO production in Hep G2 cells. The inhibitory effect of IGFs and insulin on EPO formation appears to be mediated via the IGF-I receptor.

Animals↗
PubMed1992

Monoclonal antibodies against rat kidney antigens.

The proximal tubule of the nephron is subdivided into three structurally and functionally distinct segments, which can be differentiated with the help of special methods. With the aim of producing selective markers for these three portions of the proximal tubule, we raised monoclonal antibodies against the brush border membranes of the rat kidney. Immunohistochemistry was carried out with eleven different monoclonal antibodies to sections of rat kidney and other tissues at the light- and electron-microscopical level. These monoclonal antibodies mainly detect antigens located on the brush border of the proximal tubule, and they allow a distinction between its three segments. However, some antibodies also recognize other portions of the nephron, or even the glomerulus or stromal elements. Sites recognized by the antibodies are not limited to the kidney, but staining is observed on the intestinal brush border, the intralobular ducts of the pancreas, the bile canaliculi of the liver and on the macrophage clusters of the spleen. These antibodies are interesting reagents which can be applied to study biochemical differences between brush border membranes. In addition, they recognize antigenically related sites in other organs with reabsorptive or secretory tasks.

Animals↗
PubMed1991

Amiloride enhances the secretion but not the synthesis of renin in renal juxtaglomerular cells.

In this study we have examined a potential role of the sodium/proton exchange system in the regulation of renin secretion. We found that the inhibitors of the Na+/H+ antiport, amiloride (1 mM) and ethylisopropylamiloride (EIPA, 50 microM), led to a 125% increase of renin secretion from cultured mouse juxtaglomerular cells. The stimulatory effect of EIPA on renin secretion was dependent on the extracellular concentrations of sodium and hydrogen ions. While lowering the extracellular pH from 7.3 to 7.0, and lowering [Na+]e from 130 mM to 5 mM had no effect on basal renin release, it markedly attenuated or even blunted the effect of EIPA on renin secretion. The stimulatory effect of forskolin on renin secretion, however, was not altered by decreases of extracellular pH and of sodium. Inhibition of basal renin release was achieved with angiotensin II (1 microM). In the presence of EIPA the inhibitory effect angiotensin II was markedly attenuated. Although effective on renin secretion, neither amiloride nor EIPA exerted a significant effect on the denovo synthesis of renin in cultured mouse JG cells. These findings are compatible with the idea that an amiloride-sensitive transport process, presumably the Na+/H+ exchanger, acts indirectly as an inhibitory signal transduction system for renin secretion from renal juxtaglomerular cells.

Amiloride↗
PubMed1991

Monoclonal antibodies against a human juxtaglomerular epithelioid granular cell tumour.

With the exception of the renin-angiotensin system, the molecular composition of juxtaglomerular epithelioid granular cells (JEG cells) is unknown. We demonstrate the molecular peculiarities of these modified smooth muscle cells using monoclonal antibodies produced against a benign human JEG-cell tumour. Six out of 29 different clones produced antibodies that label JEG cells nearly exclusively. Antibodies from the other clones recognize JEG cells but also granularly or homogeneously distributed antigens of proximal tubule cells. This suggests antigenic similarity between granules of JEG cells and lysosomes of proximal tubule cells. Other clones produce antibodies which tag different cytoplasmic membranes or even mast cells. The antibodies directed exclusively against JEG cells promise to be useful tools to study their physiology and pathology.

Animals↗
PubMed1991

Endothelial cells modulate renin secretion from isolated mouse juxtaglomerular cells.

Utilizing cocultures of mouse renal juxtaglomerular cells with bovine microvascular endothelial cells, we have examined whether endothelial cells exert direct influence on renin secretion from renal juxtaglomerular cells. In the presence of endothelial cells both spontaneous and forskolin (10 microM) or isoproterenol (10 microM) stimulated renin release were markedly attenuated. The stimulatory effect of the calmodulin antagonist calmidazolium (10 microM) on renin secretion was not altered by endothelial cells, whereas the stimulatory effect of ethylisopropylamiloride (50 microM) an inhibitor of sodium-proton exchange was enhanced in the presence of endothelial cells. Indomethacin (10 microM) and NG-monomethyl-l-arginine (NMMA) (1 mM) used to inhibit cyclooxygenase activity and production of endothelium-derived relaxing factor (EDRF) decreased spontaneous renin release in the presence of endothelial cells only, but had no effect on forskolin stimulated renin secretion. Endothelin (1 microM) inhibited cAMP stimulated renin release both in the absence and in the presence of endothelial cells. ATP (10 microM) which acts on both endothelial and juxtaglomerular cells via purinergic P2 receptors inhibited cAMP stimulated renin release only in the absence but not in the presence of endothelial cells. This modulatory effect of endothelial cells was no altered by indomethacin nor by NMMA. Taken together, our findings provide first evidence for a local control function of the endothelium on cAMP stimulated renin secretion from renal juxtaglomerular cells, which could in part be mediated by endothelin.

1-Methyl-3-isobutylxanthine↗
PubMed1990

[Echocardiographic functional parameters of the left ventricle as a prognostic indicator in coronary heart disease].

The value of two-dimensional cross-sectional echocardiography for the estimation of the left ventricular function had been investigated in 241 consecutive patients with suspected coronary artery disease (CAD). The day before left heart catheterization the left ventricular volumes (EDV, ESV) as well as the global left ventricular ejection fraction (EF) were calculated from the RAO-equivalent in the 2D-echo and in addition the classification of the EF was visually performed from different cross-sections. The coronary angiography showed in 208/241 patients hemodynamically effective stenoses (lumen restriction greater than 50%). For 192/208 patients there were diagnostically usable 2D-echograms as well as clinical data over an observation period of 3 years and 7 months. The 2D-echo correspond quite well to the levocardiography for the calculation of the EDV with r = 0.75, with r = 0.85 for the ESV, and with r = 0.80 for the EF. The mere visual evaluation of the EF out of the 2D-echo agreed well in 84% of the cases to the quantitative determination. During the observation period 18/192 patients died; 17/18 of these patients of cardial causes. Out of the patients with normal EF in the 2D-echo only 3.5% died, with slightly reduced EF 10% died. With highly reduced EF mortality was with 40% significantly increased (p less than 0.001). Thus in patients with CAD unfavourable long-time prognosis may be quickly recognized by their markedly reduced left ventricular function in the 2D-echocardiogram, which shows favourable correspondence to invasive data.

Adult↗
PubMed1990

Monoclonal antibodies directed against the calcium binding protein Calbindin D-28k.

We have produced 25 clones secreting antibodies directed against chicken Calbindin D-28k. Two of them, 300 and 318, recognize determinants conserved in fish, chicken, mouse, rat, rabbit, monkey and human Calbindin D-28k. We demonstrate their use in the immunohistochemical localization of Calbindin D-28k, and in the detection of Calbindin D-28k on immunoblots.

Animals↗
PubMed1989

Genetic aspects of childhood epilepsy.

The extensive studies pertinent to these problems cannot be elaborated here. We have restricted ourselves to a few representative concepts, which can be summarized as follows. The genetic aspects of convulsibility and epilepsy are highly complex phenomena. The level of convulsibility is determined by a number of different excitatory (and inhibitory) genetic factors. None of these factors is strictly specific to epilepsy. Each one is only a partial aspect of a complex genetic constitution which is strikingly common in perfectly healthy individuals, and which is related to a variety of psychic and somatic particularities. Almost all of these genetic factors seem to be polygenetically determined; in other words, they seem to reflect the actions of many genes. An increased liability to convulsions, and, finally, to epilepsy, is induced by an accumulation of these factorial sets, and, of course, by the effects of exogenous lesional factors. Special constellation of these polygenic sets may lead to the manifestation of different epileptic syndromes and may also explain the segregation of seizure types in the descendants of patients with seemingly uniform epileptic syndromes, as observed, for instance, in absence epilepsy and in juvenile myoclonic epilepsy.

Child↗
PubMed1988

Monoclonal antibodies directed against the calcium binding protein parvalbumin.

We have produced twelve monoclonal antibodies (McAB) against carp-II parvalbumin. Three of them, designated 235, 239, 267 recognize determinants conserved in fish, chicken, mouse, rat, monkey and human parvalbumin. We show their use in the qualitative detection of parvalbumin (PV) by immunohistochemistry, in the quantitation of parvalbumin by radioimmunoassay and in the detection of parvalbumin on immunoblots.

Animals↗
PubMed1983

Sulfatides in prenatal metachromatic leukodystrophy.

In one 21-week-old fetus with prenatally diagnosed metachromatic leukodystrophy, galactolipid contents were determined in the forebrain cortex, cerebellum, brainstem, spinal cord, and kidney and compared to an appropriate control. Spinal cord and kidney showed the highest sulfatide accumulation as a consequence of deficient cerebroside sulfatase activity. No increase, but a measurable amount of sulfatide, was detected in the forebrain. The prenatal neural sulfatides contained a high proportion of the hydroxy fatty acid component. The galactosyl ceramides were not reduced in the early stage of the demyelinating disease.

Central Nervous System↗
PubMed1982

Monoclonal antibodies directed to human insulin-like growth factor I (IGF I). Use for radioimmunoassay and immunopurification of IGF.

Mouse hybridomas secreting antibodies to human insulin-like growth factor I (IGF I) were produced by fusion of spleen cells of hyperimmunised mice with FO mouse-myeloma cells. Eight clones producing antibodies against human IGF I have been isolated, two of which have been characterised. One was used in a radioimmunoassay, the other for immunopurification of IGF.

Acromegaly↗
PubMed1981

Spectral analysis of EEG in the late course of primary generalized myoclonic-astatic epilepsy. I. EEG and clinical data.

The EEG of 38 patients suffering from primary generalized myoclonic astatic epilepsy since early childhood is studied in late stages of the disease. Spectral analysis shows that parietal 4-7 cps rhythms (theta rhythms) which are typical of the EEG in the early stages of the disorder can still exist in the EEG of the adult. The rhythms seem to be related to the course of the epilepsy. In the EEG of patients who still have seizures rhythms occur more often than in the EEG of patients who are free of seizures in the two years before the reexamination of their EEG. The functional anomaly producing a 4-7 cps rhythmization of the parietal EEG seems to be one pathogenetic factor in some epileptic disorders of early childhood, especially in primary generalized myoclonic-astatic epilepsy.

Adolescent↗
PubMed1981

Spectral analysis of EEG in the late course of primary generalized myoclonic-astatic epilepsy. II. Cluster analysis of the power spectra.

Cluster analysis is applied to power spectra of the EEG of 38 patients with a primary generalized myoclonic astatic epilepsy (Gundel et al. 1981). The tendency of the data to form clusters within this group is indicated by a random experiment which has been performed with the data. The clustering algorithm divided the material in seven distinct groups which may be combined to three main types of power spectra. These types are power spectra with a 10 cps peak, a 4-7 cps peak and power spectra without remarkable rhythmization. The comparison of EEG types and clinical data shows a correlation of 4-7 cps rhythms with the occurrence of seizures. 4-7 cps rhythms are interpreted as a symptom of "centrencephalic" convulsibility.

Adolescent↗
PubMed1981

[Hygienic and microbiological influences exerted on natural water biotopes by algae and the growth of water plants. 1. Communication: antibacterial properties of three water algae (Hydrodictyon reticulatum, Chlorella vulgaris, Aphanothece nidulans) in vitro (author's transl)].

The growth-inhibiting behaviour of abacterial, liquid pure cultures made up of three water algae (Hydrodictyon reticulatum, Chlorella vulgaris, Aphanothece nidulans) which were made to grow profusely in special culture containers under constant exposure to light and ventilation was examined in ten different species of microorganisms during a period of contact of 4 days both in the light and in the dark. Subjected to the test were the 5 pathogenic species Staphylococcus aureus, Klebsiella aerogenes, Pseudomonas aeruginosa, Salmonella typhimurium and Candida albicans as well the 5 bacterial contamination indicators E. coli (faecal indicator), Streptococcus faecalis (enterococci), Enterobacter aerogenes ("coliforms"), Staphylococcus epidermidis (dermic germ) and Bacillus subtilis ("contamination germ"). It was found that --Hydrodictyon reticulatum and Aphanothece nidulans exert a strong antibacterial effect, while Chlorella vulgaris provides no indication of a bacterial growth-inhibiting effect. --this antibiosis is linked with the assimilative activity of the algal cultures, as in the dark no antibacterial action is discernible --the "antibiotic principle" must be liable to transitory or rapid disintegration because the algal cultures are ineffective in the dark and also culture filtrates of 5-days old algal cultures exercise no growth-inhibiting effect. With respect to the sanitation of waters it is important to state that a profuse growth of algae produces a certain, but hardly reliable "biological water disinfection" and renders difficult the assessment of the quality of a water-course as a result of the elimination of the usual contamination indicators. Therefore, additional microbiological quality parameters must be used for assessment of pollution of swimming pools with strong algal growth.

Bacillus subtilis↗