Vector species, pasture legume host range, and impact on grain legumes of an Australian soybean dwarf virus isolate.

Soybean dwarf virus (SbDV; family Tombusviridae, genus Luteovirus, species Soybean dwarf virus) can cause damaging disease epidemics in cultivated plants of the family Fabaceae. The biological characteristics of SbDV isolate WA-8, including its vector species, host range, and impact on Australian grain legume cultivars, were investigated in a series of glasshouse experiments. Isolate WA-8 was classified as the YP strain, as it was transmitted by Acyrthosiphon pisum (pea aphid) and Myzus persicae (green peach aphid) and infected known strain indicator species. Of the 18 pasture legume species inoculated with SbDV, 12 were SbDV hosts, including eight that had not been identified previously as hosts. When inoculated with SbDV, field pea (Pisum sativum), faba bean (Vicia faba), lentil (Lens culinaris), and narrow-leafed lupin cv. Jurien were the most susceptible (70 to 100% plant infection rates), and albus lupin (Lupinus albus), chickpea (Cicer arietinum), and narrow-leafed lupin cv. Mandelup were less susceptible (20 to 70%). Over the course of three experiments, chickpea was the most sensitive to infection, with a > 97% reduction in dry above-ground biomass (AGB) and a 100% reduction in seed yield. Field pea cv. Gunyah, faba bean, and lentil were also sensitive, with a 36 to 61% reduction in AGB. Field pea cv. Kaspa was relatively tolerant, with no significant reduction in AGB or seed yield. The information generated under glasshouse conditions in this study provides important clues for understanding SbDV epidemiology and suggests that it has the potential to cause damage to Australian grain legume crops in the field, especially if climate change facilitates its spread.

A chronology of subterranean clover burr detachment mechanics and implications for seed harvestability.

Seed retention has not been evaluated for subterranean clover (Trifolium subterraneum L.), because its geocarpic seed-bearing burrs are currently harvested by suction systems. Development of improved harvest methods requires knowledge of subterranean clover seed retention characteristics and their changes with plant development. This study evaluates burr attachment and peduncle tensile strength during burr maturity until plant senescence across the three subspecies: subterraneum (cv. Dalkeith), yanninicum (cv. Monti) and brachycalycinum (cv. Mawson). Peduncle tensile strength was greater than burr-to-peduncle attachment strength for each subspecies, with peak mean peduncle strength 30-130% greater than peak mean burr-to-peduncle attachment strength. Both strength measurements decreased significantly (greater than 50% for each subspecies) as the plant senesced, which was associated with reductions in burr moisture content, and burr and peduncle diameters. Microscopy indicated a ductile to brittle transition as peduncles senesced, reducing energy absorption and increasing the likelihood of failure at defects. These results are important for the commercial production of subterranean clover seed and suggest it may be possible to harvest seed before plant senescence with dig-invert machinery, similar to that used for peanut harvesting. However, this approach would require harvesting prior to maximum seed development and the implications for seed viability and yield need to be further evaluated.

Lessons to be learned: a case study approach insulinoma presenting as a change in personality.

A 43-year-old man presented with attacks of altered behaviour over a short period of time; they were associated with episodes of hypoglycaemia. The clinical suspicion of insulinoma prompted investigations that quickly established serum insulin and C-peptide levels to be elevated at the times when blood glucose values were low. A physical lesion was found in the head of the pancreas by means of computerised tomography and endo-duodenal ultrasound scan; an octreotide scan was negative. The patient underwent laparotomy and enucleation of a benign tumour, measuring 2.6 cm in diameter, lying within the head of the pancreas; histological examination confirmed it to be an insulinoma. Postoperatively, the patient's personality gradually became more normal and his fasting blood glucose concentrations returned to within normal limits. The diagnosis and management of insulinoma are discussed in the context of this clinical case; there is also reference to the protean clinical manifestations that may occur in this condition- and its differential diagnosis.

Paradoxical platelet behaviour in diabetic ketoacidosis.

Thrombotic events may occur in patients who present with severe uncontrolled diabetes or with diabetic coma. As a possible explanation for this, platelet function was investigated at presentation with diabetic ketoacidosis and during treatment in 10 patients. Concentrations of the platelet-specific proteins, platelet factor 4 (PF4) and beta-thromboglobulin (beta TG) were elevated and fell towards normal with treatment. Despite evidence of increased aggregation in vivo, platelets from subjects with ketoacidosis were insensitive to adenosine 5'-diphosphate (ADP), sensitivity increasing with correction of ketoacidosis. Platelets from ketoacidotic diabetics were initially insensitive to the anti-aggregatory action of prostacyclin (PGI2) and became normal with treatment. Initial blood glucose concentrations correlated with log10 ADP concentrations (r = 0.72, p less than 0.01) and with log10 PGI2 ID50 (the PGI2 concentration required to half-inhibit ADP-induced aggregation) (r = 0.66, p less than 0.025). Glucose concentrations throughout the 2-week study period correlated with all log10 ADP concentrations (r = 0.32, p less than 0.005) and all log10 PGI2 ID50 concentrations (r = 0.51, p less than 0.001). The decrease in ADP sensitivity in ketoacidosis, paradoxical in view of the evidence of increased in vivo platelet aggregation, may result from an acquired platelet storage pool deficiency.

Overwhelming pneumococcal septicaemia in a patient with ulcerative colitis and splenic atrophy.

This report describes a young woman with ulcerative colitis who developed rapidly fatal pneumococcal septicaemia. Necropsy revealed splenic atrophy. This case supports the hypothesis that splenic atrophy might contribute to the morbidity of ulcerative colitis. The occurrence of splenic atrophy in ulcerative colitis is now well established. Splenic atrophy from other causes has been associated with severe bacterial infections, often pneumococcal. It has been suggested that splenic atrophy is most severe when ulcerative colitis is active and may contribute to postoperative morbidity. This case documents overwhelming septicaemia in a patient with splenic atrophy whose colitis was in remission.

Detection of dangerous malnutrition.

The assessment of malnutrition by simple methods was studied in 120 patients undergoing elective major abdominal surgery to determine which index was of the most value in predicting postoperative complications. Weight for height and weight loss were of little significant value; serum albumin less than 35 g/l was more significant (p less than 0.05) but predicted only a quarter of those patients who developed serious complications. Measurements of muscle stores by anthropometry (arm and forearm muscle circumference) predicted nearly half the patients (p less than 0.01). By far the most useful index was hand-grip dynamometry, which predicted 90% of those who developed complications (p less than 0.001). The incidence of serious complications was 6 times greater in those patients with a low grip strength. Hand-grip dynamometry appears to be a useful screening test of patients at risk, and a valuable additional test for nutritional assessment.

The metabolic effects of moderately severe upper gastrointestinal haemorrhage in man.

The metabolic effects of moderately severe gastrointestinal haemorrhage were investigated in man. Before resuscitation, patients had raised circulating concentrations of glucose, lactate, alanine, glycerol and cortisol. After urgent operation for haemorrhage, metabolite concentrations were similar to those of control patients having elective abdominal surgery, but insulin concentrations were higher and cortisol lower in haemorrhage patients. There were no significant differences in nitrogen excretion between haemorrhage patients and their controls, but urinary 3-methyl-histidine excretion by haemorrhage patients was lower indicating decreased muscle protein breakdown. Decreased amino acid release from muscle might account for previously reported imparied wound healing after haemorrhage.

Liver disease in patients with diabetes mellitus.

Liver function tests were assessed in 60 unselected out-patient diabetics stabilized on insulin or oral hypoglycaemic agents. Routine liver function tests, particularly plasma concentrations of gamma-glutamyl transpeptidase and alkaline phosphatase were elevated occasionally but rarely to more than twice the upper limit of normal. There was no correlation between measures of diabetic control and results of liver function tests. Twelve (20%) patients had evidence of gall stones, a prevalence above the expected from the community. Fourteen (23%) patients had an abnormally bright liver ultrasound echo pattern, probably indicative of fatty infiltration of the liver. This echo pattern was associated with only a minimal rise in plasma alanine amino transferase and alkaline phosphatase concentrations. It is concluded that functionally significant liver disease is uncommon amongst stabilized diabetic patients.

Relation of anthropometric and dynamometric variables to serious postoperative complications.

Prediction of serious postoperative complications by using standard anthropometric and biochemical nutritional variables was attempted in 225 patients admitted for major abdominal surgery. In 102 of the patients hand-grip dynamometry was also measured, and this proved the most sensitive test, predicting complications in 48 of the 55 patients (87%) who developed them (p < 0.001). Arm muscle circumference and forearm muscle circumference below 85% of the standard value were also of predictive value (p < 0.02 and p < 0.01 respectively); weight for height and serum albumin concentrations were less satisfactory, while weight loss of more than 10% was not significantly related to complications. Dynamometry is a useful, rapid, and inexpensive screening test for detecting malnutrition that is likely to predispose to serious postoperative morbidity.

The accuracy of ultrasound in the detection of fatty infiltration of the liver.

The association of high-amplitude echoes returned from the liver in diffuse fatty infiltration has now become well recognized. We report our experience on the accuracy with which ultrasound will detect a fatty liver. A review was made of the liver ultrasound images in patients known to have either histologically normal livers or livers with fatty infiltration. Only two of 40 patients with normal liver biopsies had a brightly reflective echo pattern, but 12 of 20 patients with fatty infiltration showed this pattern. Of the patients with histologically moderate or severe fatty infiltration, nine out of ten had a brightly reflective echo pattern.

The metabolic effects of abdominal irradiation in man with and without dietary therapy with an elemental diet.

The metabolic effects of abdominal radiotherapy were assessed in patients with pelvic neoplasms, and the effects of supplementation of the diet with an 'elemental' diet assessed. Therapeutic irradiation led to significant mean weight losses of 1.4 kg in control patients and 1.0 kg in patients receiving 'elemental' diet supplements. Irradiation was associated with small falls in plasma potassium and calcium concentrations in both groups. In the 'elemental' group there was a small increase in circulating alanine and insulin concentrations and a fall in glycerol and ketone body concentrations, but all variables remained within or close to normal basal reference ranges. Plasma albumin fell slightly but significantly in the 'elemental' diet group from 44 +/- 1 to 42 +/- 1 g/litre during treatment. Is is concluded that modern radiotherapy is no more than a modest catabolic stimulus. Long-term dietary supplementation with 'elemental' diets in ill subjects did not produce adverse effects.

Serum and urine glycosidase activities in diabetes mellitus.

Plasma and urine beta-N-acetyl glucosaminidase, beta-glucuronidase and beta-galactosidase were measured in 75 diabetics and 35 control subjects. The plasma enzyme levels were significantly elevated in patients with evidence of vascular complications. There was a negative correlation between plasma enzymes and creatinine clearance.

Hair chromium concentrations in adult insulin-treated diabetics.

Hair chromium concentrations have been measured in age- and sex-matched groups of insulin-treated diabetics and normal controls. Average concentration (+/- S.E.M.) was reduced in female (2.9 +/- 0.5 compared with 5.1 +/- 0.7 nmol/g) but not in male diabetics.

Lipid metabolites and nitrogen balance after abdominal surgery in man.

The relation of lipid metabolism to nitrogen balance was studied in patients having undergone abdominal surgery and was compared with control subjects who had fasted for a similar period. The patients had lower circulating concentrations of glycerol, non-esterified fatty acids and ketone bodies. There were inverse correlations between blood alanine and ketone body concentrations in both patients (r = -0.64, P less than 0.01) and controls (r = -0.58, P less than 0.01). Nitrogen excretion by patients (12.7 mmol/kg body weight/day +/- 1.4 s.e. mean) was greater than by controls (9.2 mmol kg(-1)d(-1) +/- 0.8, P less than 0.05), but a more marked difference was noted for urinary methyl histidine excretion of 5.1 +/- 0.5 mmumol kg(-1) d(-1) by patients and only 2.5 +/- 0.3 mumol kg(-1) d(-1) by controls (P less than 0.01), a disparity indicative of more active protein turnover after surgery.

Prevalence of diverticular disease of the colon in patients with ischaemic heart disease.

In view of the similar patterns of incidence of diverticular disease of the colon (DD) and ischaemic heart disease (IHD) in different communities, the prevalence of diverticular disease was investigated in male patients after recovery from acute myocardial infarction. A significantly higher prevalence of DD was found among infarct patients (57%) than among male control subjects (25%) matched for age and social class.

Blood intermediary metabolite and insulin concentrations after an overnight fast: reference ranges for adults, and interrelations.

Concentrations of several metabolites in deproteinized blood and plasma were determined in 100 subjects after an overnight fast, to establish reference ranges. Blood glycerol, nonesterified fatty acids, and ketone body concentrations and the 3-hydroxybutyrate/acetoacetate ratio increased with age while blood alanine concentrations delined. Serum insulin and blood alanine concentrations were also related to weight. No marked sex-related differences were found, although blood glycerol concentration was slightly higher in women. Distribution of all metabolite concentrations was positively skewed, except for glucose, but skewness could be corrected by logarithmic transformation. Skew was particularly marked for blood ketone body concentrations. Concentrations of all metabolites in plasma exceeded those in whole blood, but this was significant for only lactate and pyruvate when concentrations in plasma were compared with calculated concentrations in erythrocyte water.

The influence of early post-operative intravenous nutrition upon recovery after total cystectomy.

A retrospective review was made of the effect of early post-operative total parenteral nutrition on recovery from total cystectomy with formation of an ileal conduit. No difference in mortality or time spent in hospital after operation was noted between 2 groups receiving either total parenteral nutrition or isotonic dextrose-saline solutions.