Classification and ordination of macroinvertebrate assemblages to predict stream acidity in upland Wales

Macroinvertebrates were collected from riffles at 104 sites in upland Wales during April and July 1984. Species assemblages were ordinated by DECORANA, classified by TWINSPAN and related to stream chemistry and other environmental factors using correlation and multiple discriminant analysis. DECORANA axis 1 was most strongly correlated with pH and aluminium concentration whilst axis 2 correlated with stream gradient and flow. Four TWINSPAN site groups established in each season were also principally related to pH and aluminium concentration, and reflected overall taxon-richness; differences between groups were most apparent during spring, when catchment forest cover and taxon-richness were also related. A dichotomous key based on indicator species was established for each season with the coleopteran Hydraena gracilis Germar and the Ephemeroptera, including Baetis rhodani Pictet, important indicators at Level 1. We propose that these indicator systems may be used for the rapid detection and assessment of acid waters throughout Wales, and that the methodology is applicable generally.     

Palliative care: views of patients and their families.

OBJECTIVE--To investigate the current problems and needs of terminally ill cancer patients and their family members, and to discover their views of hospital, community, and support team services. DESIGN--Prospective study of patients and families by questionnaire interviews in the patients'' homes. SETTING--Inner London and north Kent (London suburbs). SUBJECTS--65 Patients, each with a member of their family or a career. MAIN OUTCOME MEASURES--Ratings of eight current problems and ratings and comments on three services-hospital doctors and nurses, general practitioners and district nurses, and the support team staff-obtained after a minimum of two weeks'' care from palliative care support teams. RESULTS--Effect of anxiety on the patient''s nearest career. and symptom control were rated as the most severe current problems by both patients and families; a few patients and families identified other severe problems. Families'' ratings of pain control, symptom control, and effect of anxiety on the patient were significantly worse than the patients'' ratings (p less than 0.05). Support teams received the most praise, being rated by 58 (89%) patients and 59 (91%) of family members as good as excellent. General practitioners and district nurses were rated good or excellent by 46 (71%) patients and 46 (71%) family members, but six (9%) in each group rated the service as poor or very bad, and ratings in the inner London district were significantly worse than those in the outer London district. Hospital doctors and nurses were rated good or excellent by 22 (34%) patients and 35 (54%) of family members, and 14 (22%) patients and 15 (23%) family members rated this service as poor or very bad. Negative comments referred to communication (especially at diagnosis), coordination of services, the attitude of the doctor, delays in diagnosis, and difficulties in getting doctors to visit at home. Family members were more satisfied with the services than were patients. CONCLUSIONS--Palliative care needs to include both the patient and family because the needs of the family may exceed those of the patient. Support teams and some hospital and community doctors and nurses met the perceived needs of dying patients and families, but better education and organisation of services are needed.     

Influence of exercise on cardiac and skeletal muscle myofibrillar proteins

The purpose of this study was to examine the Ca²⁺-Mg²⁺ myofibrillar ATPase and protein composition of cardiac and skeletal muscle following strenuous activity to voluntary exhaustion. Sprague-Dawley rats (200 g) were assigned to a control and exercised group, with the run group completing 25 m·min^–1 and 8% grade for 1 hour. Following activity, the myocardial Ca²⁺–Mg²⁺ myofibrillar ATPase activity -pCa relationship had undergone a rightward shift in the curve. Electrophoretic analysis revealed a change in the pattern of cardiac myofibrillar protein bands, particularly in the 38–42 Kdalton region. Enzymatic analysis of myofibrillar proteins from plantaris muscle, revealed no change in Ca²⁺ regulation following exercise. Electronmicrographic and electrophoretic analysis revealed extensively disrupted sarcomeric structure and a change in the ratio of several plantaris myofibrillar proteins. No difference was observed for myosin: Actin: tropomyosin ratios; however a dramatic reduction in 58 and 95 Kdalton proteins were evident. The results indicate that prolonged running is associated with similar responses in cardiac and skeletal muscle myofibrillar protein compositions. The abnormalities in myofibrillar ultrastructure may implicate force transmission failure as a factor in exercised-induced muscle damage and/or fatigue.     

Conformational characterization of human angiogenin by limited proteolysis

The primary structure of angiogenin is 33% identical to that of bovine pancreatic ribonuclease (RNase), but the enzymatic activities of the two proteins differ markedly. Similarly, their susceptibilities to limited proteolysis differ as well. In contrast to RNase, angiogenin totally resists proteolysis by subtilisin. Indeed, among 16 proteases examined, only endoprotease Lys-C, trypsin, and pepsin are able to cleave angiogenin. Even with prolonged incubation, endoprotease Lys-C selectively cleaves the Lys-60-Asn-61 bond; the product retains full ribonucleolytic activity. Initially, trypsin also cleaves this same bond, but with time it causes extensive degradation. Pepsin, atpH 2, cleaves the Phe-9-Leu-10 bond, to give angiogenin (10–123), which displays 15% of the native activity toward ribosomal RNA (rRNA). The susceptibility to proteolysis and/or the sites of cleavage of angiogenin and bovine RNase differ markedly despite their structural homology. These differences are considered in terms of the amino acid sequences of the two proteins.     

Inorganic-carbon uptake by a small-celled strain of Stichococcus bacillaris

Air-grown cells of a marine, small-celled (2 m diameter) strain of Stichococcus bacillaris contained appreciable carbonic-anhydrase activity but this was repressed when cells were grown on air enriched with 5% (v/v) CO₂. Assay of carbonic-anhydrase activity using intact cells and cell extracts showed all activity was intracellular in this Stichococcus strain. Measurement of inorganic-carbon-dependent photosynthetic O₂ evolution at pH 5.0, where CO₂ is the predominant form of inorganic carbon, showed that the concentration of inorganic carbon required for half-maximal rate of photosynthetic O₂ evolution [K_0.5(CO₂)] was 4.0 M for both air- and CO₂-grown cells. At pH 8.3 the K_0.5(CO₂) was 0.3 mM for air-grown and 0.6 mM for CO₂-grown cells. Sodium ions did not enhance bicarbonate utilization. Measurement of the internal inorganic-carbon pool (HCO ₃ ^– +CO₂) by the silicone-oil-layer centrifugal filtering technique showed that air- and CO₂-grown cells were able to concentrate inorganic carbon up to 20-fold in relation to the external medium at pH 5.0 but not at pH 8.3. In this alga the high affinity for CO₂ and inorganic-carbon accumulation in CO₂- and air-grown cells results from active CO₂ transport that is not dependent on carbonic-anhydrase activity.Abbreviation Hepes 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid     

Studies on the immediate and delayed leucocytosis elicited by brief (30-min) strenuous exercise

Eight healthy male volunteers exercised for two 30-min sessions starting 3 h apart on an electronically braked cycle ergometer at a work load (mean 155.9 W, SD 33.4 W) which required an oxygen consumption that was 70% of their maximal rate of oxygen uptake. Venous blood samples were taken through an indwelling cannula over a period of 6 h beginning shortly before the first bout of exercise and were analysed for routine haematological parameters and for lactate, noradrenaline, adrenaline and cortisol. Both bouts of exercise induced an immediate leucocytosis due to rises in lymphocytes and neutrophils but only the first exercise bout induced a substantial delayed neutrophilia. In at least five subjects, changes in lymphocyte and platelet numbers were correlated (Spearman's rank procedure, P less than 0.05) with simultaneous changes in the plasma concentrations of lactate, noradrenaline and adrenaline over the 6-h period studied. Increases in the plasma concentration of cortisol due to exercise correlated positively with the percentage changes in neutrophil numbers at 3 h and 6 h. These results are consistent with the suggestion that the immediate and delayed leucocytosis induced by exercise are mediated respectively by catecholamine and by cortisol.     

Effect of antigravity suit inflation on cardiovascular, PRA, and PVP responses in humans

Blood pressure, pulse rate (PR), serum osmolality and electrolytes, as well as plasma vasopressin (PVP) and plasma renin activity (PRA), were measured in five men and two women [mean age 38.6 +/- 3.9 (SE) yr] before, during, and after inflation of an antigravity suit that covered the legs and abdomen. After 24 h of fluid deprivation the subjects stood quietly for 3 h: the 1st h without inflation, the 2nd with inflation to 60 Torr, and the 3rd without inflation. A similar control noninflation experiment was conducted 10 mo after the inflation experiment using five of the seven subjects except that the suit was not inflated during the 3-h period. Mean arterial pressure increased by 14 +/- 4 (SE) Torr (P less than 0.05) with inflation and decreased by 15 +/- 5 Torr (P less than 0.05) after deflation. Pulse pressure (PP) increased by 7 +/- 2 Torr (P less than 0.05) with inflation and PR decreased by 11 +/- 5 beats/min (P less than 0.05); PP and PR returned to preinflation levels after deflation. Plasma volume decreased by 6.1 +/- 1.5% and 5.3 +/- 1.6% (P less than 0.05) during hours 1 and 3, respectively, and returned to base line during inflation. Inflation decreased PVP from 6.8 +/- 1.1 to 5.6 +/- 1.4 pg/ml (P less than 0.05) and abolished the significant rise in PRA during hour 1. Both PVP and PRA increased significantly after deflation: delta = 18.0 +/- 5.1 pg/ml and 4.34 +/- 1.71 ng angiotensin I X ml-1 X h-1, respectively. Serum osmolality and Na+ and K+ concentrations were unchanged during the 3 h of standing.(ABSTRACT TRUNCATED AT 250 WORDS)