Effect of parasympathetic denervation of liver and pancreas on glucose kinetics in man

The study aim was to investigate the role of the parasympathetic nervous system in the control of glucose tolerance in man. Glucose kinetics were determined during an oral glucose tolerance test (OGTT) in six subjects with truncal vagotomies and six control subjects. Basal plasma glucose levels in the two groups were equal; however, 20 to 40 minutes after the OGTT, glucose was higher in vagotomized compared with control subjects (P < .02). There were no differences in insulin levels between the subjects. Glucagon decreased after the OGTT in the controls, whereas in the vagotomized subjects it increased transiently and did not decrease beyond basal levels. There was no difference in basal hepatic glucose production, but suppression was greater in controls in the first 10 minutes (P < .01). Gut-derived glucose appearance increased faster and to a higher level (56.0 +/- 8 v 29.7 +/- 2.9 mumol/kg/min, P < .02) in vagotomized subjects. There were no differences in the metabolic clearance rate of glucose between the two groups. It is concluded that parasympathetic innervation of the pancreas is essential for suppression of glucagon secretion during hyperglycemia. However, abnormal glucose tolerance in vagotomized subjects is primarily due to rapid gut glucose absorption, with the denervated parasympathetic system playing only a minor role.     

Video based lifting technique coding system

Despite automation and improved working conditions, many materials in industry are still handled manually. Among the basic activities involved in manual materials handling, lifting is the one most frequently associated with low-back pain (LBP). Biomechanical analysis techniques have been used to better understand the risk factors associated with manual handling, but because these techniques require specialized equipment, highly trained personnel, and interfere with normal business operations, they are limited in their usefulness. A video based lifting technique analysis system (the VidLiTeCTM System) is presented that provides for quantifiable non-invasive biomechanical analysis of the dynamic features of lifting with high inter-coder reliability and low sensitivity to absolute errors. Analysis of results from a laboratory experiment and from field-collected videotape are described that support the reliability, sensitivity, and accuracy claims of the VidLiTeCTM System. The VidLiTeCTM System allows technicians with minimal training and low-tech equipment (a camcorder) to collect large sets of lifting data without interfering with normal business operations. A reasonably accurate estimate of the peak compressive force on the L5/S1 joint can be made from the data collected. Such a system can be used to collect quantified data on lifting techniques that can be related to LBP reporting.     

Serum intact parathyroid hormone and ionised calcium concentration in children with renal insufficiency

We report our experience of the use of an immunoradiometric assay for intact parathyroid hormone (i-PTH) and the measurement of plasma ionised calcium concentration (PCa2+) in 73 children with chronic renal insufficiency (CRI); plasma creatinine concentration (PCr) 52-856 mumol/l. There was a poor correlation between i-PTH and PCr (r = 0.10, n = 552) compared with that for C-terminal PTH and PCr (r = 0.60, n = 248), suggesting that the i-PTH assay is independent of renal function in this group of treated children. A clear response of i-PTH to a low total plasma Ca (tPCa) and PCa2+ was observed. There was a significant positive correlation between both tPCa and PCa2+ (r = 0.50, n = 389) and the fraction of Ca2+ (the fraction of tCa which was ionised) and PCa2+ (r = 0.50, n = 389). The finding of a low or normal PCa2+ with a low calculated fraction of Ca2+ was frequently observed, i.e. the measured tPCa was unexpectedly high, suggesting complexing of Ca2+ by accumulated anions in CRI. There was a poor relationship between the plasma albumin concentration and both bound plus complexed Ca (tPCa minus PCa2+) and the fraction of Ca2+ (r = 0.15 and -0.17, respectively). The positive predictive value for a raised i-PTH of a tubular reabsorption of phosphate of less than 80% was 0.87, and of an alkaline phosphatase greater than 800 U/l was 0.37.(ABSTRACT TRUNCATED AT 250 WORDS)     

Protection from Mycobacterium avium complex disease in human immunodeficiency virus-infected persons with a history of tuberculosis

Risk of Mycobacterium avium complex disease was examined in human immunodeficiency virus (HIV)-infected patients with and without a history of tuberculosis. Information was obtained by retrospective review of charts of patients in HIV clinics in 10 US cities. Among 1363 patients with <200 CD4 cells/mm3 seen at Grady Memorial Hospital (GMH), 11 (17%) of 66 with a history of a positive purified protein derivative (PPD) skin test acquired M. avium infection, while 29 (16%) of 185 who were PPD-negative (but not anergic) did not (P = .85). Only 4 (8%) of 49 GMH patients with a history of tuberculosis acquired M. avium infection compared with 252 (19%) of 1314 GMH patients without a history of tuberculosis (P = .05). Proportional hazards analysis of risk factors for M. avium infection among 441 persons with and 8702 persons without a history of tuberculosis in 9 other cities confirmed protection from M. avium infection in persons with a history of tuberculosis (relative risk, 0.52; 95% confidence interval, 0.36-0.76; P < .001). Prior tuberculosis provides protection against M. avium infection in HIV-infected persons, possibly by stimulation of antimycobacterial immunity.     

Surgery for acquired cholesteatoma in children: long-term results and recurrence of cholesteatoma

The aim of the study was to evaluate the long-term results after surgery for acquired cholesteatoma in children and to contribute to the search for predictors of recurrence. During a 15-year period, 114 children underwent surgery. The patients were re-evaluated with a median observation time of 5.8 years. At the last re-evaluation 85 per cent of the ears were dry with an intact drum. Recurrence of cholesteatoma developed in 27 ears. The cumulated total recurrence rate was 24 per cent using the incidence rate calculation, applying Kaplan-Meier survival analysis the corresponding recurrence was 33 per cent. Recurrent disease occurred significantly more frequently in children younger than eight years, with a negative pre-operative Valsalva, with ossicular resorption and with large cholesteatomas. In conclusion, young children with poor Eustachian tube function and a large cholesteatoma with erosion of the ossicular chain, are at special risk of recurrence and should be observed for several years after surgery.