Glucose and free fatty acid utilization during prolonged exercise in prepubertal boys in relation to catecholamine responses.

Ten prepubertal boys performed 60-min cycle exercise at about 60% of their maximal oxygen uptake as previously measured. To measure packed cell volume, plasma glucose, free fatty acids (FFA), glycerol and catecholamines, blood samples were drawn at rest using a heparinized catheter and at the 15th, 30th and 60th min of the exercise and after 30 min of recovery. At rest, the blood glucose concentrations were at the lowest values for normal. Exercise induced a small decrease of blood glucose which was combined with an abrupt increase of the noradrenaline concentration during the first 15 min. The FFA and glycerol concentrations increased throughout the exercise linearly with that of adrenaline. Compared to adults, the FFA uptake expressed per minute and per litre of oxygen uptake was greater in children. These results suggested that it is difficult for children to maintain a constant blood glucose concentration and that prolonged exercise provided a real stimulus to hypoglycaemia. An immediate and large increase in noradrenaline concentration during exercise and a greater utilization of FFA was probably used by children to prevent hypoglycaemia.     

The economic burden of dengue fever in the Kingdom of Saudi Arabia

Rapid urbanization, global trade, and the exceptionally great numbers of worldwide visitors during Hajj and Umrah have all placed the Kingdom of Saudi Arabia at a significant risk of introducing several vector-borne tropical diseases, such as dengue fever virus (DENV) infection. In this study we estimated DENV infection cost of illness (COI) in Saudi Arabia in the period 2013–2017, by processing national data including all declared cases recorded in referral centers in the western region, being the endemic region of the country. Using a statistically validated predictive model that was built on a representative sample of 717 laboratory-confirmed cases of DENV infection, direct costs, due to care-related expenditures, were estimated by applying the predictive equation to national data. However, indirect costs, which are due to productivity loss, were estimated using the human capital model based on gross domestic product adjusted for invalidity duration. Further, under-reporting was adjusted by using an expansion factor EF = 3. We observed highest estimated costs in 2016 with over US$168.5 Million total costs, including direct (US$29.0 Million) and indirect (US$139.5 Million) costs, for a total 4415 confirmed cases. The total DENV COI for the five years was estimated as US$551.0 Million for a total 15,369 patients (59.7%) out of 25,745 declared cases, resulting in an average cost of US$11 947.6 by patient. Depending on the year, productivity years loss costs accounted for 63.3% to 83.8% of the estimated total costs. Dengue has a substantial local economic burden that costs US$110.2 Million per year, stressing the urgent need for an effective national prevention strategy to perform considerable cost-savings besides reducing morbidity.     

Impact of dormancy regulating chemicals on salinity induced dormancy in Lasiurus scindicus and Panicum turgidum: two desert glycophytic grasses

The indigenous forage grasses Lasiurus scindicus and Panicum turgidum are candidate species for the restoration of degraded desert rangelands. The impact of five dormancy regulating chemicals on overcoming salinity-induced germination inhibition was assessed under the best germination conditions in the two species. Seeds were germinated in a series of NaCl concentrations: 0–200 mM NaCl for P. turgidum, and 0–300 mM NaCl for L. scindicus. Lasiurus scindicus seeds were more tolerant to salinity than those of P. turgidum. Twenty percent of P. turgidum seeds germinated in 100 mM NaCl and none in the higher levels, but 47.5% and 8.8% of L. scindicus seeds germinated in 100 and 200 mM NaCl, respectively. The five studied chemicals (fusicoccin, GA₃, kinetin, nitrate and thiourea) did not succeed in improving germination of non-saline treated seeds of the two species, compared to the control, except thiourea in P. turgidum. The salinity-induced germination inhibition in P. turgidum was completely alleviated by the application of gibberellic acid (GA₃), partially alleviated by the application of fusicoccin, kinetin and thiourea, but not affected by nitrate. In L. scindicus, the germination inhibition was completely alleviated by fusicoccin, GA₃, nitrate and thiourea, but partially alleviated by kinetin. For using the two grass species in restoration of degraded rangelands affected by higher salinity, the results suggest using fusicoccin, GA₃, nitrate and thiourea with L. scindicus and GA₃ with P. turgidum seeds as a preseeding treatment can overcome the problem of reduced germination.     

Use of simultaneous pressure and velocity measurements to estimate arterial wave speed at a single site in humans

It has not been possible to measure wave speed in the human coronary artery, because the vessel is too short for the conventional two-point measurement technique used in the aorta. We present a new method derived from wave intensity analysis, which allows derivation of wave speed at a single point. We apply this method in the aorta and then use it to derive wave speed in the human coronary artery for the first time. We measured simultaneous pressure and Doppler velocity with intracoronary wires at the left main stem, left anterior descending and circumflex arteries, and aorta in 14 subjects after a normal coronary arteriogram. Then, in 10 subjects, serial measurements were made along the aorta before and after intracoronary isosorbide dinitrate. Wave speed was derived by two methods in the aorta: 1) the two-site distance/time method (foot-to-foot delay of pressure waveforms) and 2) a new single-point method using simultaneous pressure and velocity measurements. Coronary wave speed was derived by the single-point method. Wave speed derived by the two methods correlated well (r = 0.72, P < 0.05). Coronary wave speed correlated with aortic wave speed (r = 0.72, P = 0.002). After nitrate administration, coronary wave speed fell by 43%: from 16.4 m/s (95% confidence interval 12.6-20.1) to 9.3 m/s (95% confidence interval 6.5-12.0, P < 0.001). This single-point method allows determination of wave speed in the human coronary artery. Aortic wave speed is correlated to coronary wave speed. Finally, this technique detects the prompt fall in coronary artery wave speed with isosorbide dinitrate.     

Iron Absorption and Blood Loss in Patients with Hiatus Hernia

Iron absorption was measured in 28 patients, 19 of whom were anaemic. The mean absorption in the anaemic patients was 39% and in the non-anaemic patients 8%. Gastrointestinal blood loss was then measured in 26 of these patients. The mean estimated blood loss in the anaemic patients was 15 ml. a day and in the non-anaemic patients 3 ml. a day. In 16 of the 19 anaemic patients symptoms of anaemia were either the sole or the major complaint.     

Enzymatic pre‐treatment of microalgae cells for enhanced extraction of proteins

Crude proteins and pigments were extracted from different microalgae strains, both marine and freshwater. The effectiveness of enzymatic pre‐treatment prior to protein extraction was evaluated and compared to conventional techniques, including ultrasonication and high‐pressure water extraction. Enzymatic pre‐treatment was chosen as it could be carried out at mild shear conditions and does not subject the proteins to high temperatures, as with the ultrasonication approach. Using enzymatic pre‐treatment, the extracted proteins yields of all tested microalgae strains were approximately 0.7 mg per mg of dry cell weight. These values were comparable to those achieved using a commercial lytic kit. Ultrasonication was not very effective for proteins extraction from Chlorella sp., and the extracted proteins yields did not exceed 0.4 mg per mg of dry cell weight. For other strains, similar yields were achieved by both treatment methods. The time‐course effect of enzymatic incubation on the proteins extraction efficiency was more evident using laccase compared to lysozyme, which suggested that the former enzyme has a slower rate of cell disruption. The crude extracted proteins were fractionated using an ion exchange resin and were analyzed by the electrophoresis technique. They were further tested for their antioxidant activity, the highest of which was about 60% from Nannochloropsis sp. The total phenolic contents in the selected strains were also determined, with Chlorella sp. showing the highest content reaching 17 mg/g. Lysozyme was also found to enhance the extraction of pigments, with Chlorella sp. showing the highest pigments contents of 16.02, 4.59 and 5.22 mg/g of chlorophyll a, chlorophyll b and total carotenoids, respectively.     

MHC-unrestricted recognition of bacteria-infected target cells by human CD8+ cytotoxic T lymphocytes.

A CD8+ alpha beta TCR+ T cell clone (A35) was isolated from the synovial fluid of a patient with post-enteric reactive arthritis caused by Yersinia enterocolitica. This clone efficiently killed autologous and allogeneic target cells that had been preincubated with live but not with heat-killed bacteria. There was no restriction by polymorphic parts of HLA-A, -B, or -C molecules and a HLA class II-deficient mutant cell line was lysed as efficiently as its normal counterpart, whereas infected HLA class I-deficient cells (Daudi cells) were not. The clone showed crossreaction between Yersinia enterocolitica, Escherichia coli, Pseudomonas aeruginosa, and Streptococcus pyogenes, but did not lyse target cells preincubated with Staphylococcus epidermidis. MAb to CD2, CD3, and CD8 efficiently blocked A35, whereas the addition of mAb to HLA class II or to HLA class I did not. This clone apparently represents a novel effector mechanism against bacteria-infected or -modified cells that could be involved in the immunopathology of reactive arthritis.     

Muscle tissue adaptations of high-altitude natives to training in chronic hypoxia or acute normoxia

Desplanches, D., H. Hoppeler, L. Tüscher, M. H. Mayet,H. Spielvogel, G. Ferretti, B. Kayser, M. Leuenberger, A. Grünenfelder, and R. Favier. Muscle tissue adaptations ofhigh-altitude natives to training in chronic hypoxia or acute normoxia.J. Appl. Physiol. 81(5):1946-1951, 1996.Twenty healthy high-altitude natives, residentsof La Paz, Bolivia (3,600 m), participated in 6 wk of enduranceexercise training on bicycle ergometers, 5 times/wk, 30 min/session, aspreviously described in normoxia-trained sea-level natives (H. Hoppeler, H. Howald, K. E. Conley, S. L. Lindstedt, H. Claassen, P. Vock, and E. R. Weibel. J. Appl.Physiol. 59: 320-327, 1985). A first group of 10 subjects was trained in chronic hypoxia (HT; barometricpressure = 500 mmHg; inspired O₂fraction = 0.209); a second group of 10 subjects was trained in acutenormoxia (NT; barometric pressure = 500 mmHg; inspired O₂ fraction = 0.314). Theworkloads were adjusted to ~70% of peak O₂ consumption(O_{2 peak}) measuredeither in hypoxia for the HT group or in normoxia for the NT group.O_{2 peak} determination and biopsies of the vastus lateralis muscle were taken before and afterthe training program.O_{2 peak} in the HTgroup was increased (14%) in a way similar to that in NT sea-levelnatives with the same protocol. Moreover,O_{2 peak} in the NTgroup was not further increased by additionalO₂ delivery during the training session. HT or NT induced similar increases in musclecapillary-to-fiber ratio (26%) and capillary density (19%) as well asin the volume density of total mitochondria and citrate synthaseactivity (45%). It is concluded that high-altitude natives have areduced capillarity and muscle tissue oxidative capacity; however,their training response is similar to that of sea-level residents,independent of whether training is carried out in hypobaric hypoxia orhypobaric normoxia.

     

Additive effects of training and high-fat diet on energy metabolism during exercise

This study was conducted to obtain additional information about the adaptations after 12 wk of high-fat diet (HFD) per se or HFD combined with endurance training in the rat using a two [diet: carbohydrate (CHO) or HFD] by two (training: sedentary or trained) by two (condition at death: rested or exercised) factorial design. Adaptation to prolonged HFD increases maximal O2 uptake (VO2max; 13%, P less than 0.05) and submaximal running endurance (+64%, P less than 0.05). This enhancement in exercise capacity could be attributed to 1) an increase in skeletal muscle aerobic enzyme activities (3-hydroxyacyl-CoA dehydrogenase and citrate synthase in soleus and red quadriceps) or 2) a decrease in liver glycogen breakdown in response to 1 h exercise at 80% VO2max. When training is superimposed to HFD, the most prominent finding provided by this study is that the diet-induced effects are cumulative with the well-known training effect on VO2max, exercise endurance, oxidative capacity of red muscle, and metabolic responses to exercise, with a further reduction in liver glycogen breakdown.     

Proteinase-3 as the major autoantigen of c-ANCA is strongly expressed in lung tissue of patients with Wegener's granulomatosis

Proteinase-3 (PR-3) is a neutral serine proteinase present in azurophil granules of human polymorphonuclear leukocytes and serves as the major target antigen of antineutrophil cytoplasmic antibodies with a cytoplasmic staining pattern (c-ANCA) in Wegener's granulomatosis (WG). The WG disease appears as severe vasculitis in different organs (e.g. kidney, nose and lung). Little is known about the expression and distribution of PR-3 in the lung. We found that PR-3 is expressed in normal lung tissue and is upregulated in lung tissue of patients with WG. Interestingly, the parenchymal cells (pneumocytes type I and II) and macrophages, and not the neutrophils, express PR-3 most strongly and may contribute to lung damage in patients with WG via direct interaction with antineutrophil cytoplasmic antobodies (ANCA). These findings suggest that the PR-3 expression in parenchymal cells of lung tissue could be at least one missing link in the etiopathogenesis of pulmonary pathology in ANCA-associated disease.