PubMed Health⌕ Search

Biomedical subjects

C Garner

Publications and source records attributed to C Garner.

At least 55 records · Page 3Linked to original sources
PubMed1994

Phosphorylation of microtubule-associated proteins MAP2a,b and MAP2c at Ser136 by proline-directed kinases in vivo and in vitro.

The microtubule-associated protein 2 (MAP2) and its juvenile splicing variant MAP2c contain a phosphorylation site at Ser136 which is part of a Ser-Pro motif. This site lies within the N-terminal region common to MAP2b and MAP2c. It has been mapped by site-directed mutagenesis of recombinant MAP2c and by a monoclonal antibody AP18 whose epitope contains the phosphorylated Ser136. In vitro this site is phosphorylated by proline-directed kinases such as MAP kinase, GSK-3, or members of the cdk family, but not by other kinases such as PKA, PKC, or CaMK-II. MAP2a,b or MAP2c isolated from brain is found to be endogenously phosphorylated at Ser136. After microinjection into several cell lines dephosphorylated MAP2 isoforms or recombinant MAP2c become also phosphorylated at Ser136 in vivo. Injection of MAP2a,b or MAP2c into living cells causes reorganization of microtubules, including bundle formation. This effect is independent of the phosphorylation at Ser136. The specificity of the phosphorylation reaction provides a tool for analyzing the role and posttranslational processing of MAP2 in nerve cell development.

3T3 Cells↗
PubMed1994

[The status of neurologic intensive care medicine in Germany].

In winter 1992/93 the working association for neurologic intensive care medicine (ANIM) undertook the continuation of a survey concerning the situation of the neurologic intensive care medicine in Germany which was first done in 1988. Altogether 51 intensive care units with in all 281 beds were questioned. 38 were located in the old, 13 in the new federal states. The intensive care units were classified into 3 groups according to equipment and organisation (ventilation-units, monitoring-units, interdisciplinary-units). The evaluation was done covering different questions like number of beds, type of clinic, number of doctors, number and training of nurses, vacant established posts in the nursing area, number and type of ventilation apparatus and monitors, possibility to measure intracranial pressure etc. In addition detailed data were given concerning the equipment of these intensive care units, the availability of major devices like CT or a neurosurgery department, the diagnosis of the patients treated on those intensive care units and the necessary average duration of staying.

Adult↗
PubMed1994

In situ detection of cytokine messenger RNAs in the eccrine sweat gland of normal human skin.

Human sweat and eccrine sweat glands contained the multifunctional polypeptide cytokines, interleukin-1 alpha and beta (IL-1 alpha and beta). To determine whether the sweat gland itself is an actual site of transcription for cytokines we performed in situ hybridization on histologic sections of normal human skin. In this report we show that the mRNAs encoding the cytokines IL-1 alpha, IL-1 beta, and tumor necrosis factor-alpha (TNF-alpha) are present in normal human skin eccrine sweat gland duct and secretory coil epithelium. These results suggest that in vivo the sweat gland is a production site for cytokine polypeptides and may contribute to the exceedingly large quantities of these cytokine proteins found in the epidermis.

Cytokines↗
PubMed1993

Serotonin activates Cl- channels in the apical membrane of rat choroid plexus epithelial cells.

The effects of serotonin on ion channel activity in epithelial cells from rat choroid plexus were examined. Serotonin (50 nM, 500 nM and 1 microM) stimulated channel activity in cell-attached patches. The current-voltage (I-V) relationship for the serotonin-activated channel gave a conductance of 26.6 +/- 1.5 pS and the current reversed at an applied electrode potential (-Vp) = 15.3 +/- 3.3 mV with a KCl-rich electrode solution (n = 8). Similar I-V relationships were obtained using electrode solutions in which K+ was replaced by other cations (Na+ and N-methyl-D-glucamine), suggesting that the serotonin-activated channels are selective to Cl-. The effect of 1 microM serotonin on channel activity was inhibited by ritanserin (30 and 100 nM) which has a high affinity for serotonin 5-HT1C receptors and 5-HT2 receptors. Spiperone (30 nM), which binds weakly to 5-HT1C receptors but has a high affinity for 5-HT2 receptors, did not inhibit the actions of serotonin. These data suggest that serotonin increases Cl- channel activity by acting on the 5-HT1C receptors on the epithelium.

Animals↗
PubMed1993

Little evidence for anti-endothelial-cell antibodies in microscopic polyarteritis and Wegener's granulomatosis.

Sera from patients with a vasculitis and controls were investigated for the presence of anti-endothelial cell antibodies(AECA), anti- neutrophil cytoplasmic antibodies(ANCA) and anti-myeloperoxidase (MPO) antibodies. Only 19% of patients with Wegener's granulomatosis and 2% of patients with microscopic polyarteritis had AECA. Our data suggests that AECA are a minor antibody system in vasculitis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

Little evidence for anti-endothelial cell antibodies in microscopic polyarteritis and Wegener's granulomatosis.

We studied sera from patients with vasculitis and controls for the presence of anti-endothelial cell antibodies (AECA) and correlated these with disease type, anti-neutrophil cytoplasmic antibodies (ANCA) and anti-myeloperoxidase (MPO) antibodies. AECA were detected by a cellular ELISA on cultured human umbilical vein endothelium. AECA were found in the sera of one of 43 patients with microscopic polyarteritis (2%), five of 27 patients with Wegener's granulomatosis (19%), three of 23 patients with an idiopathic glomerulonephritis (13%), none of eight patients with rheumatoid arthritis and three of 12 patients with rheumatoid vasculitis (25%). In patients with a vasculitis AECA titres were higher in sera with a positive ANCA as compared with ANCA negative sera although the difference was not significant (P = 0.0702) and there was no correlation between AECA and anti-MPO titres (r = 0.1171 P = 0.114). AECA binding was not enhanced following upregulation of endothelial ICAM-1 and ELAM-1 by TNF alpha. This study shows that AECA occur infrequently in microscopic polyarteritis and Wegener's granulomatosis, and are not a major antibody system in these vasculitides.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1992

Two types of chloride channel in the apical membrane of rat choroid plexus epithelial cells.

The patch clamp technique has been used to study ion channel activity in the apical (ventricular) membrane of epithelial cells from the rat choroid plexus. Two different classes of Cl(-)-selective channel were identified. A low conductance (26 pS) channel which was the predominant feature in cell-attached and inside-out patches. The occurrence of this channel appeared to increase in tissue bathed in forskolin. It was activated in inside-out patches by increasing the Ca2+ concentration at the intracellular face of the membrane and by depolarising potentials. The second class of channel was observed infrequently (2% of patches) and appeared to be similar to 'maxi'-Cl- channels which have been described in many other cell types. It had a conductance of 320 pS, opened to sub-conductance levels and displayed a marked voltage dependence in inside-out patches. The possible contribution of these channels to Cl- transport during the production of cerebrospinal fluid (CSF) is discussed.

Animals↗
PubMed1991

Heparin treatment in sinus venous thrombosis.

Treatment of sinus venous thrombosis (SVT) is controversial. Although heparin has been used for this condition, many investigators have opposed its use because of the frequent occurrence of intracranial haemorrhage (ICH) and SVT. Therefore we have evaluated anticoagulation with adjusted-dose intravenous heparin for treatment of aseptic SVT in a randomised, blinded (patient and observer), placebo-controlled study in 20 patients (10 heparin, 10 placebo). The clinical course of the two groups, as judged by a newly designed SVT-severity scale, started to differ in favour of the heparin group after 3 days of treatment (p less than 0.05, Mann-Whitney U-test) and the difference remained significant (p less than 0.01) after 8 days of treatment. After 3 months, 8 of the heparin-treated patients had a complete clinical recovery and 2 had slight residual neurological deficits. In the placebo group, only 1 patient had a complete recovery, 6 patients had neurological deficits, and 3 patients died (p less than 0.01, modified Fisher's exact test). An additional retrospective study on the relation between heparin treatment and ICH in SVT patients was based on 102 patients, 43 of whom had an ICH. 27 of these patients were treated with dose-adjusted, intravenous heparin after the ICH. Of these 27 patients, 4 died (mortality 15%), and 14 patients completely recovered. Of the 13 patients that did not receive heparin after ICH, 9 died (mortality 69%) and only 3 patients completely recovered. We conclude that anticoagulation with dose-adjusted intravenous heparin is an effective treatment in patients with SVT and that ICH is not a contraindication to heparin treatment in these patients.

Adult↗
PubMed1991

New monoclonal antibodies reacting with bile ducts: further insights into the pathogenesis of bile ductular proliferation in biliary diseases.

We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described.

Adult↗
PubMed1991

Expression of various microtubule-associated protein 2 forms in the developing mouse brain and in cultured neurons and astrocytes.

A cDNA probe specific to microtubule-associated protein 2 (MAP2) was used to study the expression of the mRNAs encoding the high- and low-molecular-weight MAP2 variants in cultured neurons and astrocytes. The timing and relative abundance of these MAP2 transcripts and of their encoded proteins were also studied in the developing cerebral hemispheres and cerebellum of the mouse. A 9-kb mRNA, known to encode high-molecular-weight MAP2, was expressed in cultured astrocytes, albeit at a lower level than in neurons. The 6-kb transcript, recently shown to encode low-molecular-weight MAP2 (MAP2c), was expressed in neurons and was the predominant MAP2 transcript of the astrocytes. The level of the 9- and 6-kb transcripts decreased at late stages of astroglial and neuronal cell culture. The 9-kb mRNA was detected in the cerebellum and cerebral hemispheres at every developmental stage. Although the levels of this mRNA varied slightly in the cerebral hemispheres, its expression was biphasic in the cerebellum. This might be explained by the differences in timing of development of the various neuronal cell types formed in these two brain areas. The 6-kb transcript was detected only at early developmental stages in the two brain areas. Correlating the temporal expression of the 9-kb mRNA to that of high-molecular-weight MAP2 indicates that the accumulation of this protein is in part regulated at a cytoplasmic level.

Aging↗
PubMed1990

Delivery of iron to human cells by bovine transferrin. Implications for the growth of human cells in vitro.

Following suggestions that transferrin present in fetal-bovine serum, a common supplement used in tissue-culture media, may not bind well to human cells, we have isolated the protein and investigated its interaction with both human and bovine cells. Bovine transferrin bound to a human cell line, K562, at 4 degrees C with a kd of 590 nM, whereas human transferrin bound with a kd of 3.57 nM, a 165-fold difference. With a bovine cell line, NBL4, bovine transferrin bound with the higher affinity, kd 9.09 nM, whereas human transferrin bound with a kd of 41.7 nM, only a 5-fold difference. These values were reflected in an 8.6-fold difference in the rate of iron delivery by the two proteins to human cells, whereas delivery to bovine cells was the same. Nevertheless, the bovine transferrin was taken up by the human cells by a specific receptor-mediated process. Human cells cultured in bovine diferric transferrin at 40 micrograms/ml, the concentration expected in the presence of 10% fetal-bovine serum, failed to thrive, whereas cells cultured in the presence of human transferrin proliferated normally. These results suggest that growth of human cells in bovine serum could give rise to a cellular iron deficiency, which may in turn lead to the selection of clones of cells adapted for survival with less iron. This has important consequences for the use of such cells as models, since they may have aberrant iron-dependent pathways and perhaps other unknown alterations in cell function.

Animals↗
PubMed1990

The limited potential of special ambulance services in the management of cardiac arrest.

For six months a survey was made of all the patients in the Nottingham District Health Authority who died or who were brought to hospital after a cardiac arrest outside hospital. During this period just under half of the emergency ambulance shifts were covered by specially trained crews with defibrillators. During the study period the ICD coding of death certificates indicated that 894 (25%) of the 3575 deaths were due to ischaemic heart disease. During this period the ambulance service received 17,749 emergency calls, which included 445 patients who had cardiac arrests outside hospital. One hundred and forty seven of these patients were carried by ambulances equipped with defibrillators and resuscitation was attempted in 83. Seven patients survived to leave hospital. The special ambulance service was cost effective--a simple calculation suggests that the cost per life saved was approximately 2600 pounds, but it seems unlikely that special ambulance services will materially affect community fatality rates from ischaemic heart disease.

Adult↗
PubMed1989

Cerebrospinal fluid penetration after single or multiple dosage with ticarcillin/clavulanate.

Penetration of ticarcillin and clavulanate into the cerebrospinal fluid was studied in ten patients with varying degrees of impairment of the blood-brain barrier. In general, penetration of both drugs was relatively low and variable (5.4 +/- 5.8% for clavulanate and 2.0 +/- 4.0% for ticarcillin) but markedly better in those patients with impaired blood/brain barrier.

Adolescent↗