Hyperparathyroidism and cellular mechanisms of gastric acid secretion

Patients with hyperparathyroidism appear to be a particular risk for peptic ulcer disease. To test the hypothesis that hypercalcemia or parathyroid hormone plays a role in promoting ulcer disease, we studied the effect of varying concentrations of extracellular calcium on acid secretion using in vitro isolated rabbit gastric glands. Acid secretion was assessed by the accumulation of carbon 14-labeled aminopyrine (14C-AP). Glands were incubated with varying calcium concentrations in the unstimulated state and with histamine or carbachol (10(-7) to 10(-4) mol/L) in 1 or 2 mmol/L calcium medium. The effect of parathyroid hormone was also examined under identical conditions. Compared to 1 mmol/L standard calcium medium, unstimulated 14C-AP accumulation was significantly inhibited (p less than 0.05) at both lower (0.33 mmol/L) and higher (2 and 2.5 mmol/L) calcium concentrations. Accumulation of 14C-AP in response to histamine stimulation was unaffected by alteration of extracellular calcium (p greater than 0.2). Carbachol-stimulated 14C-AP accumulation was significantly augmented (p less than 0.01) by an increase in calcium concentration from 1 to 2 mmol/L. The addition of parathyroid hormone (10(-7) to 10(-4) mmol/L) alone or in combination with carbachol or histamine (10(-6) mmol/L) incubation did not alter 14C-AP accumulation. These data suggest that elevations in extracellular calcium play an active role in the potentiation of cholinergic-mediated gastric gland acid secretion and may thereby play a role in hyperparathyroid-related ulcer disease.     

Fear of falling in older adults: a guide to its prevalence, risk factors, and consequences.

Fear of falling, defined as a lack of self-confidence that one may avoid falls while doing everyday activities, may have serious consequences for elderly people. This article examines the prevalence, risk factors, and consequences of fear of falling in the elderly population; methods for assessing those fears; and suggests evidence-based interventions. Incorporating successful strategies into programs to reduce falling can result in improved patient outcomes as well as decreased healthcare utilization and costs.     

Lack of C-erbB-2 protein expression in pulmonary carcinoid tumours.

To determine if amplification of the C-erb-B2 proto-oncogene could be correlated with prognosis in carcinoid tumours, 49 pulmonary carcinoid tumours (26 typical, 23 atypical) were examined using a polyclonal antibody to the C-terminal peptide of the C-erb-B2 protein sequence. No C-erb-B2 gene product could be shown: the demonstration of C-erb-B2 does not seem to help, therefore, in determining diagnosis or prognosis in pulmonary carcinoid tumours.     

Age- and sex-specific pediatric reference intervals for biochemistry analytes as measured with the Ektachem-700 analyzer

Using the Ektachem-700 multilayer film analyzer, we defined age- and sex-specific reference intervals for 20 analytes in sera from a healthy population of neonates and children ages one to 19 years. Upper and lower normal reference intervals for each analyte were determined by nonparametric methods as the 0.975 and 0.025 fractiles, respectively. Newborns have lower concentrations of total protein and albumin, and higher concentrations of phosphate, bilirubin, and enzymes in serum than older children do. Concentrations of urea, glucose, calcium, phosphate, and bilirubin change rapidly postnatally. Outside the neonatal period, no significant age- or sex-related difference was found for plasma glucose, serum amylase, conjugated or unconjugated bilirubin, or lipase. There was no sex-related difference in reference intervals for albumin, total protein, calcium, phosphate, or urea. However, concentrations of uric acid and creatine kinase are much higher in postpubertal boys than in girls. Alkaline phosphatase values peak later in boys. Except for lactate dehydrogenase and gamma-glutamyltransferase, the reference intervals defined here do not differ strikingly from data derived with use of other analyzers. The age- and sex-related trends are independent of method. However, each laboratory should determine the degree to which these reference ranges can be directly applied to analyses performed with another analyzer.     

VASCULAR COMPLICATIONS OF ELECTIVE LOWER LUMBAR DISC SURGERY

Lower lumbar disc surgery is an extremely common operation from which vascular complications are reported rarely. However vascular injury can occur with perforation of the anterior longitudinal ligament. External haemorrhage is uncommon and the true cause of the patient's hypotension may be misdiagnosed. If the hypotension is severe or prolonged laparotomy is indicated, to prevent exsanguination and to effect a repair of the vascular injury. Alternatively, if the injury is missed, an arteriovenous fistula may develop; this diagnosis may be delayed for months or years. One case of severe haemorrhage following lower lumbar disc surgery is reported and a further 69 cases of similar arterial injury have been reviewed from the world literature.