Cortisol levels in blood and urine of trotting horses

Statistical analysis of normally occurring cortisol levels in serum and urine of horses served to recommend thresholds for this corticosteroid in these body fluids, as application of exogenous cortisol as well as ACTH may elevate the cortisol concentrations above the proposed threshold. The present study contributes to the general issue of how to establish thresholds for trotting horses upon sportive examination. 100 randomly selected post competition serum and urine samples, respectively, were submitted to cortisol analysis by means of HPLC. Concentrations of the endogenous corticosteroid in serum and urine followed a log-normal distribution with mean values of 61 and 49 ng/ml, respectively. The probability was 1: 100,000 to exceed concentration limits of 230 (serum) and 394 ng/ml (urine). Designation of thresholds for cortisol has proven problematic and is discussed here.     

Improved liquid-chromatographic determination of caffeine in plasma

We describe a rapid, specific, and sensitive liquid-chromatographic micro-method for caffeine in plasma. Each plasma sample can be assayed within about 15 min of its receipt. Samples are denatured with acetonitrile, centrifuged, and the supernate is chromatographed on a reversed-phase column. Only 100 microL of plasma is required, and concentrations as low as 0.3 mg/L can be measured accurately. Other xanthines and their metabolites do not interfere. The small sample required makes the procedure ideally suited for measuring caffeine in the plasma of infants and small animals as well as adults.     

Effects of intravenous administration of sodium hyaluronate on carpal joints in exercising horses after arthroscopic surgery and osteochondral fragmentation

OBJECTIVE: To evaluate the effects of arthroscopic surgery, osteochondral fragmentation, and treatment with IV administered hyaluronate on histologic, histochemical, and biochemical measurements within the carpal joints of horses. ANIMALS: 12 clinically normal horses, 2 to 7 years of age. PROCEDURE: Horses had an osteochondral fragment created at the distal aspect of the radiocarpal bone of 1 randomly chosen middle carpal joint to simulate osteochondral fragmentation. Horses were treated with 40 mg of hyaluronate or saline solution (placebo) intravenously once a week for 3 consecutive weeks (days 13, 20, and 27 after surgery). Treadmill exercise proceeded 5 days per week beginning 15 days, and ending 72 days, after surgery. Clinical evaluations were performed at the beginning and end of the study. Synovial fluid samples were obtained aseptically from both middle carpal joints on days 0, 13, 20, 27, 34, and 72 after surgery, and total protein, inflammatory cell, hyaluronate, glycosaminoglycan, and prostaglandin E2 concentrations were measured in each sample. All horses were euthanatized on day 72. Synovial membrane and articular cartilage were obtained for histologic evaluation. Articular cartilage samples were also obtained aseptically for determining glycosaminoglycan content and chondrocyte synthetic rate for glycosaminoglycans. RESULTS: Horses treated with hyaluronate intravenously had lower lameness scores (were less lame), significantly better synovial membrane histologic scores, and significantly lower concentrations of total protein and prostaglandin E2 within synovial fluid 72 days after surgery, compared with placebo-treated horses. Treatment with intravenously administered hyaluronate had no significant effects on glycosaminoglycan content, synthetic rate or morphologic scoring in articular cartilage, or other synovial fluid measurements. CONCLUSION: Intravenously administered hyaluronate appears to alleviate signs of lameness by interacting with synoviocytes, and by decreasing production and release of inflammatory mediators.     

Detection of 1,N6-ethenoadenine in rat urine after chloroethylene oxide exposure

The four etheno adducts of vinyl chloride formed in DNA, 1,N6-ethenoadenine (epsilonA), 3,N4-ethenocytosine, 1,N2-ethenoguanine and N2,3-ethenoguanine were previously reported to be released from DNA by a family of enzymes in the base-excision repair pathway (Dosanjh et al., Proc. Natl Acad. Sci. USA, 91, 1024-1028, 1994; Hang et al., Carcinogenesis, 17, 155-157, 1996; Hang et al., Proc. Natl Acad. Sci. USA, 94, 12869-12874, 1997). Adducts excised from DNA by glycosylases are usually excreted in urine and have been reported to be potential biomarkers of DNA damage in exposed individuals. In this study, we report the detection of epsilonA in the urine of rats exposed to chloroethylene oxide (CEO) using immunoaffinity columns made with specific monoclonal antibodies for enrichment, followed by quantitation by HPLC with fluorescence detection. Chemical analysis of urine samples revealed the presence of a compound chromatographically identical to authentic epsilonA standard. This compound was confirmed by mass spectral analysis. EpsilonA was present in urine of control and CEO-treated rats, with the latter having up to 50-fold greater amounts. The cumulative excretion of epsilonA reached a plateau between 24 and 48 h post-exposure. While it is clear that CEO treatment results in increased excretion of epsilonA, the exact source of the adduct is unknown. When rats were administered epsilonA i.v., approximately 10% of the administered dose was excreted in urine. This research demonstrates that urinary excretion of epsilonA may be a potential biomarker for in vivo alkylation of DNA and nucleotide pools.     

Worsening enterocolitis in neonates: diagnosis by CT examination of urine after enteral administration of iohexol

Perforation, a severe complication of necrotizing enterocolitis (NEC), has a high mortality rate. Recently, we presented a new technique for evaluation of NEC: measuring the CT attenuation coefficient of urine after oral administration of iohexol. We present three cases of neonates with NEC who demonstrated serial increases in urine CT attenuation coefficients, all of whom subsequently deteriorated clinically and radiographically. Surgery in all three cases confirmed severe necrosis and/or perforation. These three cases suggest that the CT attenuation coefficient of urine after oral administration of iohexol may be a more sensitive indicator of NEC severity, progression, and perforation than clinical evaluation and radiography. More investigation is necessary, but eventually, this noninvasive technique may be able to decrease morbidity and mortality by predicting the need for surgical intervention or more aggressive medical management of NEC before perforation occurs.     

Pulmonary function in horses with recurrent airway obstruction after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively

OBJECTIVE: To determine changes in clinical signs of disease and response to pulmonary function testing in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. ANIMALS: 6 horses with inducible and reversible heaves. PROCEDURE: Episodes of heaves were induced by exposure (challenge) to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone dipropionate, parenterally administered dexamethasone, aerosolized propellant [control]), and respiratory frequency and subjective assessment of respiratory effect were determined twice daily. Maximal change in pleural pressure (delta-Pplmax), pulmonary resistance (RL), and dynamic compliance (Cdyn) was determined on days 0, 7, 10, 14, and 21. RESULTS: The RL and delta Pplmax were increased, and Cdyn was decreased in all horses in response to natural challenge. Beclomethasone reduced RL on day 10, reduced delta Pplmax on days 14 and 21 and increased Cdyn on day 14. Dexamethasone reduced RL and delta Pplmax on days 10, 14, and 21 and increased Cdyn on days 10 and 14. Respiratory effort (subjective assessment) improved after 2 and 3 days of beclomethasone and dexamethasone administration but rebounded to pretreatment values 1 and 3 days after discontinuation of drugs. CONCLUSIONS: Pulmonary function testing responses and clinical signs of airway obstruction were improved by administration of beclomethasone. The magnitude of response to aerosolized beclomethasone generally was less marked than the response to parenterally administered dexamethasone. Higher or more frequent dosing of aerosolized beclomethasone may be necessary to achieve the anti-inflammatory response to parenterally administered dexamethasone.     

Effects of chronic caffeine administration on respiration and schedule-controlled behavior in rhesus monkeys

The effects of chronic caffeine administration on ventilation and schedule-controlled behavior were studied in 12 adult rhesus monkeys. In seated subjects prepared with a head plethysmograph, ventilation was measured during exposure to air (normocapnia) and to elevated levels of CO2 (3%, 4% and 5%) mixed in air (hypercapnia). Acute administration of caffeine (10.0-30.0 mg/kg i.m.) produced marked, dose-dependent increases in ventilation during conditions of normocapnia and hypercapnia. However, daily administration of caffeine (10.0 mg/kg i.m.) for 8 consecutive days resulted in tolerance to its respiratory-stimulant effects that was surmountable with higher doses. Caffeine-tolerant subjects also were cross-tolerant to theophylline, an active metabolite of caffeine, and to rolipram and Ro 20-1724, selective phosphodiesterase inhibitors. When chronic administration was terminated and the acute effects of caffeine were redetermined, sensitivity returned to levels obtained before chronic administration within 9 days. Drug effects on behavior were studied in monkeys trained to respond under a fixed-interval schedule of stimulus termination. Acute administration of caffeine (1.0-30.0 mg/kg i.m.) produced significant rate-increasing effects on fixed-interval responding, but chronic administration resulted in tolerance that was insurmountable, such that no dose increased responding above control rates. Although the time course for development and loss of tolerance to the behavioral effects of caffeine corresponded closely with respiration, cross-tolerance did not extend to the behavioral effects of rolipram. Chronic caffeine administration had little effect on caffeine metabolism or clearance, which indicated that caffeine tolerance was pharmacodynamic. The results suggest that different neurochemical mechanisms mediate the effects of caffeine on respiration and behavior, and that inhibition of type IV phosphodiesterase plays a prominent role in caffeine-induced respiratory stimulation.     

Food allergy to peanuts in France--evaluation of 142 observations

BACKGROUND: The increase in frequency of peanut allergy and fatal cases have been reported. OBJECTIVES: The objective of this study is to document the severity of food allergy to peanuts by evaluating the reactive dose of peanuts and to search for the role of peanut oil. METHODS: This study is carried out on the basis of 142 observations collected according to the same diagnostic methodology in two allergy centres in France. Skin-prick-tests were performed with peanut powder, peanut oil and peanut oil proteinic extract. Labial provocation tests were performed on 121 patients. The reactive dose of peanuts and the role of peanut oil were determined by standardized oral provocation tests in 50 and 62 patients respectively. The data are computerized and the data bank includes 509 food allergic patients. RESULTS: Allergy to peanuts represents 28% of food allergies and occurs under 1 year of age in 46% of cases, under 15 years of age in 93%. The clinical features were atopic dermatitis (40%), angioedema (37%), asthma (14%), anaphylactic shock (6%) and digestive symptoms (1.4%). The specific IgE were class 3 or higher in 80% of cases. The total reactive dose was less than 100 mg in 25% of cases, from 100 mg to 1 g in 62.5%. All patients reacted to a dose of less than 7.1 g. The threshold of peanut reactivity was lower than the threshold of egg reactivity. An allergy to peanut oil was demonstrated in 14 patients. CONCLUSION: The severity of peanut allergy and the early onset of the occurrence of this allergy is documented. The role of residual allergenic proteins in peanut oil is established by positive skin-prick tests to proteic extracts from peanut oil and by double-blind placebo-controlled challenges to peanut oil. The increased consumption of allergens in the form of peanut oil and fats can contribute to the occurrence or persistence of symptoms and may be suspected to increase the risk of sensitisation.     

Characteristics of delayed excretion of flavonoids in human urine after administration of Shosaiko-to, a herbal medicine

There has been little explanation of herbal medicines by modern medical sciences, including pharmacokinetics, whereas physicians follow empirical indications written in classical literature. Recent reports of herb-induced adverse reactions compelled us to proceed the investigation of a herbal medicine Shosaiko-to (TJ-9) from a pharmacokinetic point of view. To five healthy volunteers, a single 5 g dose of TJ-9, consisting of 7 herbs, was administered. We conducted HPLC analysis of the timed-urine specimens to disclose the type and amount of compounds excreted. Excretion rate-time curves were analyzed individually. Four flavonoids, liquiritigenin, baicalein, wogonin and oroxylin A, were found both in the urine and TJ-9. The glycosides in TJ-9 were absorbed after microflora hydrolysis. Davidigenin, which was not found in TJ-9, was an intestinal metabolite of liquiritigenin. Also, two flavanones, S-dihydrowogonin and S-dihydrooroxylin A, were identified as the metabolites of wogonin and oroxylin A, respectively. Excretion rate-time curves of the flavonoids were divided into three types of structure-dependent absorption, i.e. (1) the fast absorption of herbal-origin aglycons, (2) the moderately-delayed absorption of aglycons derived from herbal glycosides, and (3) markedly-delayed absorption after the molecular transformation of herbal compounds. Individual excretion profiles seemed to depend on microflora activities. Two types of flavanones, S-dihydrowogonin and S-dihydrooroxylin A, were found in a half of the volunteers, suggesting there might be two kinds of volunteers, namely, rapid and poor metabolizers of flavonoids.     

Alteration in adrenocortical function in horses with recurrent airway obstruction after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively

OBJECTIVE: To determine alteration in adrenocortical function in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. ANIMALS: 6 horses with inducible and reversible heaves. PROCEDURE: Episodes of heaves were induced by exposure to moldy hay and straw for 7 days (natural challenge). Horses then underwent treatment (aerosolized beclomethasone, parenterally administered dexamethasone, and aerosolized propellant) for 7 days. Horses remained in the mold-contaminated environment for 7 days after discontinuation of drugs. Adrenocortical function was determine by serial evaluation of cortisol concentration in serum obtained on days 0, 7, 9, 12, 14, 16, 19, and 21. Adrenocorticotropic hormone stimulation testing was performed in 4 horses/treatment group on days 0, 7, 14, and 21. RESULTS: Endogenous cortisol production was suppressed in beclomethasone- and dexamethasone-treated horses within 2 days of treatment but recovered to values similar to those in propellant-treated horses approximately 2 and 4 days after discontinuation of drugs. Serum cortisol concentration in propellant-treated horses gradually decreased during the study and was significantly lower than baseline on days 14, 16, 19, and 21. Mean increase in serum cortisol concentration in response to ACTH stimulation testing after beclomethasone and dexamethasone administration did not differ significantly from the response observed in propellant-treated horses. CONCLUSIONS: Aerosol and parenteral administration of beclomethasone and dexamethasone, respectively, suppressed adrenocortical function; however, endogenous cortisol production resumed approximately 2 and 4 days after discontinuation of drugs. Responsiveness to ACTH stimulation testing was not affected by the 7-day treatment period.     

GLC determination of nylidrin in human urine samples

A method for the detection of nanogram quantities of nylidrin in human urine is described. The method involves beta-glucuronidase hydrolysis, extraction with chloroform, derivatization by silylation, and GLC determination. The suitability of the method was tested by analysis of urine samples of subjects after oral ingestion of nylidrin hydrochloride.     

Detection of cytomegalovirus in urine using DNA-DNA hybridization

A discussion is conducted on the results of the application of the technique for hybridizing nucleic acids to the detection of cytomegalovirus (CMV) in urine samples. For this purpose, 2 probes from 2 different regions of the genome of the AD169 strain of CMV were used. The results were compared with those obtained by the technique for the detection of early fluorescent antigens (DEFA) in 2 groups of patients at risk of suffering from CMV infections. After assessing the usefulness of the two probes in detecting CMV in urine samples, it was shown that probe B from the region which codes the synthesis of early viral proteins had a coincidence and specificity levels regarding the reference test (DEFA) significantly superior to that of probe A. The results of hybridization may be ready within 48 and 72 hours. The qualification of the technique fo its application to virological diagnosis is discussed.     

Flow-injection spectrophotometric determination of diclofenac sodium in pharmaceuticals and urine samples

The localization of two salmon-type gonadotropin-releasing hormone (sGnRH) precursors, pro-sGnRH-I (short type) and pro-sGnRH-II (long type), was investigated by using in situ hybridization techniques in the brain of the landlocked sockeye salmon, Oncorhynchus nerka. We used 30-mer oligonucleotide probes complementary to pro-sGnRH-I and pro-sGnRH-II cDNA. No significant differences were observed in the localization of sGnRH neurons expressing pro-sGnRH-I and pro-sGnRH-II mRNAs; both were expressed in the olfactory nerve, the olfactory bulbs, the regions between the olfactory bulb and telencephalon, the ventral telencephalon, the preoptic area, and the hypothalamus. Almost all sGnRH neurons examined co-expressed both precursors. The expression of two sGnRH precursors in the same neuron and the wide distribution of such neurons in the brain suggest that there are no functional differences between the two precursors.