Beta-hydroxy beta-methylbutyrate (HMB) supplementation does not influence the urinary testosterone: epitestosterone ratio in healthy males.

Six healthy, recreationally active, males undertook two weeks supplementation with beta-Hydroxy beta-Methylbutyrate (HMB). Supplementation was in capsule form with 3 g consumed each day in three even doses of 1 g at main meals. Mid stream urine samples were collected prior to, as well as, after one and two weeks of supplementation and subsequently analysed for testosterone and epitestosterone. The testosterone: epitestosterone ratio was not affected by 2 weeks of HMB supplementation (mean +/- SD baseline 1.02 +/- 0.68; week one 0.98 +/- 0.61; week two 0.92 +/- 0.62). Our results support the claim that supplementation with HMB at the doses recommended will not influence the urinary testosterone: epitestosterone ratio and thus not breach doping policies of the International Olympic Committee for exogenous testosterone or precursor administration.

Solid-phase extraction and derivatisation methods for beta-blockers in human post mortem whole blood, urine and equine urine.

This paper details various rapid and sensitive methods for the extraction and derivatisation of propranolol, metoprolol, sotalol, atenolol, pindolol, timolol, oxprenolol, alprenolol and penbutolol in equine urine and in human post mortem whole blood and urine. Three solid-phase extraction methods are described involving the use of either XtrackT XRDAH515, Bond Elut Certify or Sep-Pak C18 cartridges. Two derivatisation methods are also described involving the formation of cyclised silyl or pentafluoropropionate derivatives with either chloromethyldimethylchlorosilane or pentafluoropropionic anhydride, respectively. Gas chromatographic-mass spectrometry analysis was carried out in select-ion monitoring mode. All these methods were evaluated using drug-free human post mortem blood, urine and equine urine fortified at various levels with the beta-blockers mentioned above. The application of some of these methods on a forensic case study is also presented. This work does not include samples from equine administration trials of beta-blockers.

Cortisol concentrations in blood and urine of horses.

A survey of the concentrations of cortisol in blood and urine samples taken from thoroughbred and standardbred horses after racing is presented. Statistical analysis showed the only significant difference between thoroughbred and standardbred horses was a higher cortisol concentration in thoroughbred urine. Urine volume and pH had no significant influence on the urinary cortisol concentration, however 9.5% of the urinary cortisol variation could be explained due to the influence of plasma cortisol concentration. The results of cortisol and ACTH administrations are also shown and compared with the survey results.

A chromatography system for drug identification.

A classification system is described for drugs using thin-layer chromatography (TLC), gas-liquid chromatography (GLC) and ultraviolet (UV) spectrophotometry. The TLC classifications are based on division of the plate into zones relative to a set of mixed drug standards. The GLC classification is based on Kovats' retention indices. The procedure for classifying drugs is presented, together with a list of over 200 classified drugs.

Recovery of dengue viruses from tissues of experimentally infected rhesus monkeys.

A tissue explant culture technique for the recovery of dengue virus from experimentally infected monkey tissue is described and compared with tissue culture assay of tissue triturates and co-cultivation of trypsinized cells in cell cultures. The most efficient technique was one in which minced tissue was explanted in co-culture with dengue virus-susceptible LLC-MK2 monkey kidney cells. This technique shows promise of being useful for detection of virus in autopsy material from fatal dengue hemorrhagic fever cases.

Nonspecific factors in monkey tissues and serum causing inhibition of plaque formation and hemagglutination by dengue viruses.

Normal monkey serum and the supernatant fluid from different triturated monkey tissues have been studied for the presence of nonspecific arbovirus hemagglutination and plaque forming inhibitors of dengue viruses types 1, 2, 3, and 4. Hemagglutination inhibition (HI) activity was present in most tissue specimens and demonstrated a significant gradient of effectiveness starting with, respectively, serum, spleen, adrenal, and lung having a high degree of activity, whereas skin, heart, muscle, brain, and liver demonstrated low HI titers. A slightly reversed gradient of effectiveness was obtained for the case of dengue virus inhibition of plaque formation with bile, liver, thymus, spleen, and adrenal giving high 50% plaque reduction titers and heart, muscle, serum, skin, and fat demonstrating little or no activity. Analysis by Sephadex G-200 chromatography and sucrose density gradient centrifugation suggests that HI and plaque formation inhibition are independent activities of normal serum or tissue constituents or both. Also, in addition to the physical methods of characterization, chemical treatment by absorption with kaolin or acetone extraction indicate both phenomena to be the result of the action of lipids or lipoproteins.

Viral antibody levels and clinical status in acute exacerbations of chronic bronchitis: a controlled prospective study.

A controlled prospective study was made of a group of patients with chronic bronchitis, in which serum antibodies against a group of viruses and Mycoplasma pneumoniae were estimated at regular intervals. Sixteen significant rises in antibody titre were shown, of which eight were associated with clinical acute exacerbations of bronchitis. In individual patients no correlation was found between the number of acute exacerbations or the aetiological agent and persistent change in ventilatory function as expressed by the F.E.V.(0.75).This study was compared with the results of a previous parallel investigation of the same patients done to study the significance of rhinovirus infections. In the present investigation 12% of the acute exacerbations were associated with the 11 agents tested compared with 14% associated with rhinoviruses in the earlier work.