Hormonal and metabolic responses of older adults to resistance training in normobaric hypoxia.

PURPOSE: In young adults, the hormonal responses to resistance exercise are amplified by normobaric hypoxia. Hormone concentrations and metabolism are typically dysregulated with age, yet the impact of hypoxia on these responses to resistance exercise are uncharacterised. Therefore, this study aimed to characterise the acute and chronic hormonal and metabolic responses of older adults to resistance training in normobaric hypoxia. METHODS: Adults aged 60-75 years completed 8 weeks of resistance training in either normoxia (20.9% O2; n = 10) or normobaric hypoxia (14.4% O2, n = 10) twice weekly at 70% of their predicted 1-repetition maximum. Growth hormone, glucose, lactate, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), cortisol, total testosterone, adrenaline, noradrenaline and dopamine were quantified at pre- and post-training, and in the 60 min following the first training session (untrained state) and the last training session (trained state). RESULTS: Eight weeks of training in hypoxia did not affect the resting levels of the hormones or physiological factors measured. However, hypoxia significantly blunted the acute growth hormone response in the 15 min following the last training session at week eight (43.87% lower in the hypoxic group; p = 0.017). This novel and unexpected finding requires further investigation. All other hormones were unaffected acutely by hypoxia in the 60 min following the first and the last training session. CONCLUSION: Chronic resistance training in normobaric hypoxia supresses the growth hormone response to exercise in older adults. All other hormones and metabolic markers were unaffected both acutely and chronically by hypoxia.

The Dichaete gene of Drosophila melanogaster encodes a SOX-domain protein required for embryonic segmentation.

We have cloned and characterised a member of the High Mobility Group superfamily of genes from Drosophila, Sox70D, which is closely related to the mammalian testis determining gene SRY. Sox70D corresponds to the dominant wing mutation Dichaete. Homozygous deletions of the Sox70D gene and recessive lethal Dichaete alleles have a variable embryonic segmentation phenotype. Dichaete is expressed in early embryos in a dynamic pattern reminiscent of gap and pair-rule genes and is required for the appropriate expression of the primary pair-rule genes even skipped, hairy and runt. The molecular nature of Dichaete and its expression pattern during early embryogenesis suggest that the gene plays a key role in early development; the variability in both the segmentation phenotype and the effects on pair-rule gene expression suggests that this role is to support the transcriptional regulation of key developmental genes rather than directly regulate any one of them.

Peripheral versus central intravenous nutrition: comparison of two delivery systems.

Forty-six surgical patients who required intravenous nutrition (IVN) were randomly allocated to receive complete IVN by a peripheral (n = 23) or central (n = 23) venous delivery system. The peripheral IVN system combined a fine-bore silicone catheter with lipid-based nutrient solutions whereas the central system used a conventional glucose-based nutrient regimen and a single-lumen central venous catheter. The incidence of catheter complications and the complication-free system function over time were compared. Problems of venous access were not observed with peripheral IVN but occurred with one central catheterization. Three patients with central venous catheters developed bacteraemia but only one incident was thought to be catheter related (bacterial translocation). There were no such episodes with peripheral IVN. Peripheral catheterization was not associated with infective phlebitis, although late-onset chemical phlebitis occurred on four occasions after a mean(s.e.m.) time of 22.8(6.1) days, representing a daily risk of phlebitis of 0.009. There was no significant difference in the probability of complication-free system function with time between peripheral and central IVN (P = 0.14). The fine-bore silicone catheter peripheral IVN delivery system resulted in long-term phlebitis-free infusion for periods that were similar to those of single-lumen central catheterization by life-table analysis.

Tortuous and aberrant external iliac artery precluding radical retropubic prostatectomy for prostate cancer.

A sixty-eight-year-old black man with clinical Stage A1 (T1a) adenocarcinoma of the prostate was found to have a tortuous and redundant left external iliac artery directly overlying the superior aspect of the prostate gland. The location of this blood vessel precluded radical retropubic prostatectomy. To our knowledge, this is the first reported example of this clinical situation. Computer-generated three-dimensional imaging from the computed tomography scan allowed accurate assessment of the vascular anomaly.

Fine-bore peripheral catheters versus central venous catheters for delivery of intravenous nutrition.

We present a descriptive study of 229 consecutive inpatients requiring intravenous nutrition. These patients received either complete peripheral intravenous nutrition via a fine-bore silicone catheter (n = 80) or short Teflon catheter (n = 15) or received conventional central intravenous nutrition (n = 134). Nutrient delivery was similar for both systems, providing 0.2-0.4 g N.kg-1 x day-1 and 0.13-0.15 mJ.kg-1 x day-1 from preparations containing 4.3 MJ/L total energy (65-75% lipid: 25-35% glucose for peripheral support and 100% glucose for central delivery) with 6 g N/L. We compared the incidence of catheter complication and the probability of catheter function over time for the peripheral and conventional central systems. Venous access complications were seen only with central venous catheterization (10.4%). Chemical phlebitis occurred in 17% of fine-bore catheters and 91.4% of Teflon catheters. The infective phlebitis rate of fine-bore silicone catheters was 1.02% and daily risk of phlebitis 0.016%, with no instance of device-related bacteremia or sepsis. Central-line microbial contamination (21.7%) and catheter-related sepsis (3%) were significantly greater (p < 0.0005, chi 2 goodness-of-fit test) than with fine-bore silicone and Teflon catheters. The probability of complication-free function against time was similar (0.75 < p < 0.90, log-rank test) in fine-bore silicone catheters and central venous catheters. We conclude that fine-bore silicone catheters provide long-term phlebitis-free delivery of complete peripheral intravenous nutrition.

Levels and temporal trends of trace element concentrations in vertebral bone.

An X-ray fluorescence analysis study of iron, zinc, rubidium, strontium, and lead in ashed vertebral column whole bone samples of 51 sudden death victims in Western Australia gave median values of 893, 213, 25, 108, and 25 ppm, respectively. Highly significant concentration-age Spearman correlations were observed for iron-age (rs = 0.45, P less than .004), Zn-age (0.43, P less than .006), and lead-age (0.63, P less than .001), the mean per annum rates of increase being 26, 0.4, and 0.8 ppm, respectively, and marked concentration-concentration correlations were found for iron-lead (0.44, P less than .003) and strontium (0.30, P less than .06). The median zinc concentrations for the male and female subsets are 216 and 205 ppm, respectively; the corresponding values for strontium are 100 and 120 ppm.

Characterization of thymus-derived lymphocyte subsets in acute Epstein-Barr virus-induced infectious mononucleosis.

Changes in thymus-derived (T) lymphocyte subpopulation numbers were studied in patients with acute and convalescent Epstein-Barr virus (EBV)-induced infectious mononucleosis (LM). T cell subsets were characterized by the presence of Fc receptors for IgG (TG), for IgM (TM) or by the absence of either receptor (Tnon-M, non-G). We found that in acute IM, total numbers of T and B lymphocytes were elevated (p less than 0.01). Of the T lymphocyte subsets, the total number of Tnon-M, non-G lymphocytes was increased six fold compared to normal subjects (p less than 0.001) and included the majority of the atypical T lymphocytes. The number of total TG and TM lymphocytes was moderately increased (p less than 0.05). In convalescent IM patients, the number of total T cells remained slightly elevated (p less than 0.02) whereas proportions and absolute numbers of B lymphocytes and T cell subsets returned to near normal levels. Thus, acute Epstein-Barr virus-induced IM is associated with a T lymphocytosis which is composed predominantly of atypical T cells which lack detectable Fc receptors for IgG or IgM.

Early prenatal diagnosis of Hurler's syndrome with termination of pregnancy and confirmatory findings on the fetus.

PIP: Mucopolysaccharidosis Type I (Hurler's syndrome) was diagnosed in an 18 week old fetus of a woman with 1 affected child by direct assay of glycosaminoglycans in amniotic fluid. Subsequently the fetus was aborted by hysterotomy and diagnosis was confirmed by analyzing glycosaminoglycans in fetal liver, electron micrographs isozymes of galactosidases, and fetal skin sulfate turnover. In this case the amnio tic fluid contained 78% dermatan and heparan sulfates. The fetal liver contained 28.8% dermatan sulfate and 62.4% heparan sulfate among the soluble glycosaminoglycans. Some translucent lysosomal vacuoles with osmiophilic inclusions were evident in liver but not in central nervous system. Isozymes A and B of alpha-galactosidase and beta-galactosidase- B were very low in fetal tissues compared with age-matched controls. 5 other lysosomal enzymes were slightly elevated upon assay with fluorescent substrates. Sulfate turnover studies in cultured fetal skin cells showed excessive accumulation but enhanced release rates in presence of pooled normal human serum (Hurler corrective factor). When these studies were done, the enzyme defect in Hurler's syndrome was known to be alpha-L-iduronidase, but no substrate was available commercially.^ieng

Incidence of -thalassaemia trait among Cypriots in London.

The incidence of beta-thalassaemia trait among Cypriots in London is about 14%, and the birth rate of children with thalassaemia major is 0.6%. The high incidence of the beta-thalassaemia gene among Cypriots suggests the desirability of screening Cypriot school-leavers for thalassaemia trait and following up any incidentally discovered cases with family studies and genetic counselling.