Renal vascular reactivity in jaundice

Obstructive jaundice is associated with a predisposition to hypotension and acute renal failure that may be related to changes in renovascular responsiveness, particularly to norepinephrine (NE). This study was undertaken to investigate changes in vascular response to NE and to determine how these changes are related to prostaglandins. Kidneys from bile duct-ligated (BDL) rabbits (n = 5) were perfused with Krebs' solution at 7.65 ml/min, and the response to varying boluses of NE (0.78 to 6.24 micrograms) was measured as changes in perfusion pressure. When compared with sham-operated control kidneys (n = 8), a significantly blunted response was seen at all doses tested. The NE response was further assessed by measuring force development in mounted segments of main renal arteries (MRAs) (n = 8) and interlobar arteries (ILAs) (n = 6) from BDL rabbits and sham-operated controls (MRA, n = 8; ILA, n = 6). The dose-response curves were significantly depressed in both MRAs and ILAs from BDL animals. In addition, MRAs from sham-operated control animals exhibited decreased response to NE after incubation for 1 hour in jaundiced serum. This attenuated response of MRAs to NE was prevented when indomethacin (5 mg/kg) was given to BDL rabbits before death (n = 9) or when 10(-6)mol/L of indomethacin was added to jaundiced serum during incubation (n = 6). These results indicate that obstructive jaundice induces a decreased vascular contractile response in rabbits to NE and that this effect is mediated by prostaglandins.     

Intense immunoreactivity for Mn-superoxide dismutase (Mn-SOD) in cholinergic and non-cholinergic neurons in the rat basal forebrain

The immunohistochemical localization of manganese (Mn)-superoxide dismutase (Mn-SOD) was studied in the rat basal forebrain using polyclonal antibodies to Mn-SOD. Neurons of the basal forebrain exhibit a high density of Mn-SOD immunoreactivity. Double immunostaining with a monoclonal antibody to choline acetyltransferase demonstrated that both cholinergic and non-cholinergic neurons in the basal forebrain are intensely immunoreactive for Mn-SOD.     

Neuroradiological analysis of small infarcts in deep subcortical structure detected by CT

We studied angiographic findings of 56 patients who were diagnosed as lacunar infarcts in the basal ganglia or deep subcortical white matter based on clinical symptomatology and brain computed tomography. In 26 patients with CT lesions less than 15 mm in diameter, only eight (31%) showed minor angiographic findings. In 30 patients with lesion of 15 mm or more, however, 22 (73%) had abnormal angiographic findings. Fourteen of the 22 patients had minor irregularities, three had 25-75% stenosis, five had 75% less than stenosis at the bifurcation of the common carotid artery or the horizontal portion of the middle cerebral artery. Our findings support the notion that a small lesion on CT can result from an occlusion of the perforating artery itself and a larger lesion is much related to the major vessel or heart diseases, i.e., emboli from the parent artery or heart, obstruction of perforators at their origin by an atheromatous plaque of the horizontal portion of the middle cerebral artery, or terminal zone infarct due to hemodynamically significant stenotic lesion. In patients with a larger deep infarct on CT, further investigation of the arteries in the carotid-axis and heart is important for determination of therapeutic indication.     

Integrity of perforant path fibers and the frequency of action potential independent excitatory and inhibitory synaptic events in dentate gyrus granule cells.

Whole-cell voltage clamp recordings in 400 microns thick hippocampal slices revealed discrete excitatory and inhibitory postsynaptic currents which persisted at synapses on granule cells following abolition of action potentials with 1 microM tetrodotoxin (TTX). The conductances associated with excitatory amino acid and GABAA receptor mediated events had mean peaks of 200 and 800 pS, and decayed monoexponentially with time constants of 5.6 and 5.3 ms. At a holding potential close to the normal resting membrane potential of granule cells (-80 to -90 mV), the frequency of glutamate/aspartate mediated spontaneous excitatory postsynaptic currents (sEPSCs) was decreased from 2.04 Hz in slices cut parallel to the plane of the perforant path to 0.87 Hz in slices cut in a plane that disrupted the distal perforant path fibres, suggesting that presynaptic integrity influences the rate of action potential independent neurotransmitter release. The orientation of the slicing had no effect on the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs).     

A nursing approach to the management of type IIA hyperlipidemia: case study of a young adult

This case study illustrates the chronic nature of hyperlipidemia type IIa and the important contribution of the nurse in helping the client adjust life style, manage complex health regimes, and cope with the uncertainty of disease progression and its associated risks.     

Issues in community care services

In the first part of this series on issues in ward management facing charge nurses, Helen Evers addresses the problem of communication between hospital and community on patient discharges. Recent years have seen the development of liaison and co-ordinator posts whose incumbents aim to facilitate planned and organised discharge procedures, but the appointment of such personnel may not provide a complete answer to the problem. The ultimate arbiter of effective transition from hospital to home is more likely to be the quality of communication between charge and district nurse.     

Human alpha-fetoprotein and its purification by chromatography on immobilized estrogens.

Human alpha-fetoprotein (AFP) was isolated from human abortive tissue by biospecific chromatography on immobilized estrogens. The most effective sorbents were: estrone-0-3-hemisuccinyl-hexamethylenediamine-Sepharose CL 4B and diethylstilbestrol-diasoanisole-sulfonyl-oxyethyl-Sepharose CL 4B. As elution solution the most optimum was 10% buffered aqueous butanol. Taking into consideration the data obtained, one can conclude that AFP in human biological fluids is bound to immobilized estrogens. Butanol extraction deestrogenizes AFP, and as a result human AFP acquires affinity to immobilized estrogens. During rechromatography on immobilized diethylstilbestrol, it was possible to obtain AFP preparations of about 95% purity. The present results provide the opportunity to work out new methodological approaches to human AFP isolation using biospecific chromatography on immobilized estrogens.     

Carcinoma of thyroid--clinical presentation and outcome.

The clinical, biochemical and pathological features of 31 patients with thyroid carcinoma managed at Hospital Universiti Sains Málaysia, Kubang Kerian from 1985 to 1989 were analyzed. There were 25 females and 6 males. The types of carcinoma were: papillary-17 cases; follicular-10 cases; medullary-2 cases and anaplastic-2 cases. For papillary carcinoma the mean age of the patients was 52.9 years. For follicular carcinoma the mean age was 48.3 years, for medullary carcinoma, 48.5 years and for anaplastic, 74.5 years. All patients had pre-existing goitre except for 2 and most presented with advanced disease. The mean duration of symptoms for papillary carcinoma was 3.7 years, follicular carcinoma 1.6 years, medullary carcinoma 13.5 years and anaplastic carcinoma 6 months. 12 patients presented with goitre of increasing size; 9 had compression symptoms; 4 presented with cervical lymph node enlargement and 6 presented with bony pains of whom 2 had paraplegia. None of the patients were ever thyrotoxic or hypothyroid. Treatment in general was unsatisfactory because of patients' non-acceptance of surgery and/or radioactive iodine.     

Assembly, disassembly, and exchange of glial fibrillary acidic protein

The kinetics and dynamics of glial fibrillary acidic protein (GFAP) assembly was explored by a fluorescence energy transfer assay method. Purified GFAP was stoichiometrically labeled at a single cysteine residue with fluorescein-maleimide. Soluble labeled GFAP in a low ionic strength buffer was assembled into 10 nm filaments by rapidly increasing the ionic strength, and the kinetics of GFAP assembly was monitored by the reduction in fluorescence due to self-quenching of fluorescein. The extent of fluorescence quench correlated with both the formation of 10 nm filament morphology and the amount of protein pelleted at 12,000g. The assembly of GFAP is critically dependent upon both protein and magnesium ion concentration, and at the critical concentration for GFAP assembly is approximately 40 micrograms/ml. Disassembly of GFAP filaments was also observed as a relief of fluorescence quenching after dilution of labeled GFAP filaments. When labeled GFAP filaments were mixed with an excess of unlabeled filaments, a rapid increase of fluorescence was observed, which is due to an exchange of subunits between labeled and unlabeled GFAP filaments. These results indicate that GFAP filaments are dynamic structures and that a small pool of kinetically active unassembled GFAP subunits are in a dynamic equilibrium with assembled GFAP filaments. The ability of GFAP to assemble, disassemble, and undergo subunit exchange has important implications for the organization and dynamics of astroglia cell cytoskeleton during development and in response to injury.