Does more sleep matter? Differential effects of NREM- and REM-dominant sleep on sleepiness and vigilance.

We investigated effects of NREM and REM predominant sleep periods on sleepiness and psychomotor performances measured with visual analog scales and the psychomotor vigilance task, respectively. After one week of stable sleep-wake rhythms, 18 healthy sleepers slept 3hours of early sleep and 3hours of late sleep, under polysomnographic control, spaced by two hours of sustained wakefulness between sleep periods in a within subjects split-night, sleep interruption protocol. Power spectra analysis was applied for sleep EEG recordings and sleep phase-relative power proportions were computed for six different frequency bands (delta, theta, alpha, sigma, beta and gamma). Both sleep periods presented with similar sleep duration and efficiency. As expected, phasic NREM and REM predominances were obtained for early and late sleep conditions, respectively. Albeit revealing additive effects of total sleep duration, our results showed a systematic discrepancy between psychomotor performances and sleepiness levels. In addition, sleepiness remained stable throughout sustained wakefulness during both conditions, whereas psychomotor performances even decreased after the second sleep period. Disregarding exchanges for frequency bands in NREM or stability in REM, correlations between outcome measures and EEG power proportions further evidenced directional divergence with respect to sleepiness and psychomotor performances, respectively. Showing that the functional correlation pattern changed with respect to early and late sleep condition, the relationships between EEG power and subjective or behavioral outcomes might however essentially be related to total sleep duration rather than to the phasic predominance of REM or NREM sleep.

Benzocaína e eugenol como anestésicos para o quinguio (Carassius auratus) / Benzocaine and eugenol as anesthetics for golden fish (Carassius auratus)

Avaliaram-se os tempos de indução e recuperação de quinguios (Carassius auratus) expostos a dois anestésicos, eugenol e benzocaína. Foram utilizados 128 juvenis com peso médio de 2,07±0,53g e comprimento total médio de 5,51±0,56cm. A benzocaína mostrou ser mais eficiente do que o eugenol em relação ao tempo, tanto para indução ao coma quanto para a recuperação à fuga e também no que diz respeito à sobrevivência. As doses de benzocaína com melhores resultados foram de 87,5 e 100mg.L-1. O eugenol proporcionou demora na indução e na recuperação dos animais, além de ter apresentado mortalidades quando as doses anestésicas foram elevadas.

The aim of this work was to evaluate the induction and recuperation time of quinguio (Carassius auratus) exposed to two anesthetics, eugenol and benzocaine. 128 juveniles with 2.07±0.53g of average weight and 5.51±0.56cm of total length were used. The benzocaine proved to be more efficient than the eugenol regarding the time in inducing a coma and recovering flight, as well as survival. The better results of benzocaine doses were 87.5 and 100mg.L-1. The eugenol resulted in a delay of animal induction and recovery, and also presented mortalities when the anesthetics doses were increased.

Digestibilidade do fósforo em dietas como estratégia nutricional para redução de efluentes da tilapicultura / Digestibility of phosphorus in feed as a nutritional strategy for reduce of effluents from tilapia culture

Avaliou-se a digestibilidade do fósforo em dietas isoproteicas e isoenergéticas contendo 28 por cento de proteína bruta e 3000kcal de ED/kg com porcentagens de 0,8 e 1,2 por cento de fósforo total para juvenis de tilápia-do-nilo (Oreochromis niloticus). Os parâmetros de qualidade da água apresentaram diferenças significativas (P<0,05) para o fósforo total, ortofosfato, DBO5 e condutividade. A digestibilidade das dietas foi de 75,3 por cento para os peixes alimentados com 0,8 por cento de fósforo total e de 77,5 por cento para os alimentados com 1,2 por cento de fósforo total. As taxas de eficiência da absorção do fósforo foram de 74,8 por cento e 76,3 por cento para as tilápias alimentadas com 0,8 por cento e 1,2 por cento de fósforo, respectivamente. O aumento do percentual de 0,4 por cento de fósforo na dieta levou ao acréscimo de 55 por cento de fósforo na água. Dessa forma, a utilização de valores abaixo de 0,8 por cento de fósforo total é uma estratégia que auxilia na redução do impacto causado pelos efluentes oriundos da criação de peixes, sem comprometer a eficiência do aproveitamento das dietas pelas tilápias.

The objective of this study was to evaluate the digestibility of phosphorus in isonitrogenous and isocaloric diets containing 28 percent crude protein and 3000kcal DE/kg at different levels of total phosphorus, 0.8 percent and 1.2 percent, in Nile tilapia juveniles (Oreochromis niloticus). The water quality parameters presented significant differences (P<0.5) for total phosphorus, orthophosphate, BOD5 and conductivity. The digestibility of diets was 75.3 percent for fish fed 0.8 percent total phosphorus and 77.5 percent for treatment with 1.2 percent total phosphorus. It was observed that the efficiency rate in phosphorus absorption among the treatments was 74.3 and 76.3 percent for tilapia fed 0.8 percent and 1.2 percent phosphorus, respectively. It can be concluded that a percentage increase of 0.4 percent phosphorus in tilapia diets contributes to the increase of 55 percent of phosphorus in water and the lower phosphorus input in the diet can be a nutritional strategy to be practiced. Thus, it will help to reduce the impact caused by effluents from fish farming, without lowering the efficiency of tilapia diet utilization.

[Religion and brain functioning (part 1): are our mental structures designed for religion?]. / Religion et fonctionnement du cerveau (partie 1): nos structures mentales nous prédisposent-elles à la religion?

Religions are seen everywhere in the world. Two main theories are competing to explain this phenomenon. The first one is based on the assumption that our cognitive structures are predisposing us to nurture religious beliefs. Religion would then be a by-product of mental functions useful for survival. Examples of these mental functions are children credulity, anthropomorphism and teleology. The second one hypothesizes that religion is maintained trough direct adaptation benefits occurring in cooperation exchanges. In particular, religion could function as an insurance mechanism given by the religious group. It is likely that both theories are complementary and useful to explain why religion is a universal phenomenon in the human species.

Dose proportionality of oral etoricoxib, a highly selective cyclooxygenase-2 inhibitor, in healthy volunteers.

To assess dose proportionality of etoricoxib across the anticipated clinical dose range, a single panel of 12 healthy subjects was administered single oral doses of etoricoxib of 5, 10, 20, 40, and 120 mg in an open, two-part, five-period crossover study. Plasma samples were collected aftereach dose and analyzed for etoricoxib concentrations. The pharmacokinetics of etoricoxib appear to be linear over the entire dose range examined, from 5 to 120 mg. Etoricoxib was found to be well tolerated across the 5 to 120 mg dose range.

MIB-1 immunohistochemistry in clinical stage I nonseminomatous testicular germ cell tumors predicts patients at low risk for metastasis.

BACKGROUND: The clinical Stage I of nonseminomatous germ cell tumors (NSGCT) is inaccurate in 30% of patients. In previous studies on tumor biologic risk factors, low tumor proliferation rates predicted a group of patients at low risk for occult metastatic disease. The goal of this study was to confirm the immunohistochemical assessment of tumor proliferation using MIB-1 (Ki-67 receptor) in a different patient cohort with different investigators to prove the method's reliability. METHODS: Orchiectomy specimens of 78 patients with clinical Stage I NSGCT (50 patients with pathologic Stage I and 28 patients with pathologic Stage II disease, all patients underwent retroperitoneal lymph node dissection) were retrospectively analyzed by histopathologic reevaluation and MIB-1 immunostaining. RESULTS: Mean MIB-1 values between the two pathologic stages differed significantly (51.5% MIB-1 positive tumors cells in pathologic Stage I and 75.1% MIB-1 positive tumor cells in pathologic Stage II disease; P = 0.02). Using a 70% cutoff value, pathologic stages were correctly classified in 69% of cases (sensitivity of 86%, specificity of 60%, negative predictive value of 88%, and positive predictive value of 55%). Compared with traditional risk factors such as percentage of embryonal carcinoma and vascular invasion, in multivariate analysis, MIB-1 was the best predictor of patients at low risk for metastasis. CONCLUSIONS: This study in a different patient population with different investigators confirmed previous results of MIB-1 staining to predict a group of patients with clinical Stage I NSGCT who were at low risk for metastasis. The method is simple and reproducible to improve risk classification in low stage testicular carcinoma. Using this technique, a group of patients at very low risk for metastasis can be identified. [See editorial counterpoint on pages 1641-5 and reply to counterpoint on page 1646, this issue.]

Treatment of Strongyloides stercoralis infection with ivermectin compared with albendazole: results of an open study of 60 cases.

Ivermectin is highly effective against animal intestinal nematodes and is used in the treatment of onchocerciasis in humans. A study was undertaken to compare the efficacy of the drug with that of albendazole in the treatment of uncomplicated strongyloidiasis. Sixty patients with confirmed Strongyloides stercoralis infection were enrolled in an open randomized study and given either albendazole, 400 mg/d for 3 d or ivermectin, 150-200 micrograms/kg in a single dose. Efficacy and tolerance were evaluated on days 7, 30 and 90. Each visit included a parasitological examination of 3 stool specimens, using saline and Kato smears and formalin-ether and Baermann concentrations. Fifty-three patients were eligible for evaluation. Parasitological cure was obtained in 24 of the 29 patients treated with ivermectin (83%) and in 9 of the 24 patients who were given albendazole (38%); ivermectin was significantly more effective than albendazole (P < 0.01). Clinical and biological adverse reactions were negligible in both treatment groups. The 20 patients who failed therapy were given a second treatment course with 150-200 micrograms/kg of ivermectin in a single dose or on 2 consecutive days. Sixteen patients were cured and the other 4 had only incomplete follow-up. Ivermectin therefore constitutes an acceptable therapeutic alternative for uncomplicated strongyloidiasis.

Ivermectin--clinical trials and treatment schedules in onchocerciasis.

Initial clinical trials with ivermectin were performed in patients with both roundworm infestation and onchocerciasis. Obvious clinical safety allowed for rapid progression through 5-30-50-100-150-200 mcg/kg in infected patients. Initial studies showed some effect at 50 mcg/kg; subsequent double-blind controlled studies, either with placebo or diethylcarbamazine (DEC), confirmed the efficacy of ivermectin as well as further defining its safety profile. Absence of adverse eye findings or serious systemic reactions justified the further open trials. Studies of patients treated at 6, 12, or 18 month intervals showed a long lasting effect of ivermectin in reducing skin microfilaria counts. Phase III studies confirmed safety and efficacy and further refined the dose to 150 mcg/kg every 12 months. Large trials in Liberia and other countries in West Africa, and subsequently under Onchocerciasis Control Program (OCP), included approximately 120,000 persons carefully followed during which few patients with serious adverse experiences were reported. These extensive field trials confirmed the relative safety allowing for broad distribution of ivermectin in programs not able to provide physician monitoring.

Ivermectin for human strongyloidiasis and other intestinal helminths.

Since ivermectin, a mixture of 2 closely related macrocyclic lactones, has proven highly effective against animal intestinal nematodes, trials were undertaken to determine its efficacy against human intestinal nematodes. We tested 110 patients with strongyloidiasis and 90 with enterobiasis; many had other intercurrent intestinal nematode infections. Stool examinations were done before and after patients were given a single dose of oral ivermectin capsules (50, 100, 150, or 200 micrograms/kg body wt); 55 recipients of 100 or 200 micrograms/kg doses received a second identical dose the next day. Kato and saline smears, ethyl acetate concentration, modified Baermann's technique, and Harada-Mori cultures were repeated; cure was defined as complete absence of eggs and/or larvae from stools tested 30 days after dosing. Ivermectin was well tolerated. Overall cure rates at all doses 30 days after therapy averaged 88% for strongyloidiasis, 100% for ascariasis, 85% for trichuriasis, and 85% for enterobiasis. Ancylostoma duodenale and Necator americanus were little affected.

Analysis of pharmaceutical dosage forms for oxfendazole: II. Simultaneous liquid chromatographic determination of oxfendazole and trichlorfon in equine paste.

A reverse phase liquid chromatographic procedure is described for the simultaneous determination of oxfendazole [2-(methoxycarbonylamino)-5-phenylsulfinylbenzimidazole] and trichlorfon [(2,2,2-trichloro-1-hydroxyethyl)phosphonic acid dimethyl ester] in equine paste. The sample is extracted by sonication in methanol. Insoluble excipients are removed by centrifugation and an aliquot plus internal standard are diluted with dilution solvent (water-acetonitrile-phosphoric acid, 80 + 20 + 1). The samples are filtered and injected onto a Partisil-5 ODS-3 column with acetonitrile-0.01 M phosphate buffer pH 6.0 (20 + 80) as mobile phase. Method specificity is confirmed using an absorbance rationing technique. The method yields mean recoveries of 100.9 and 100.0% for trichlorfon and oxfendazole, respectively. Dependence of chromatographic performance characteristics on mobile phase organic content, pH, and buffer concentration is also reported.

Analysis of pharmaceutical dosage forms for oxfendazole: I. Reverse phase liquid chromatographic determination of oxfendazole in swine premix.

A reverse phase liquid chromatographic (LC) procedure is described for quantitating oxfendazole (2-(methoxycarbonylamino)-5-phenylsulfinylbenzimidazole] in swine premix. Sample preparation consists of extracting oxfendazole with an acetone-methanol mixture. An aliquot of the extract is then centrifuged to separate undissolved premix excipients. Internal standard is added to the supernate and the sample is further diluted with water-acetonitrile-phosphoric acid (80 + 20 + 1). Oxfendazole is quantitatively determined using a Partisil-5-ODS-3 column with acetonitrile-0.01 M phosphate buffer (pH 6.0) as the mobile phase. The method is stability specific and yields a mean recovery of 101.1 +/- 0.4% for the 1.35% premix formulation. The dependence of chromatographic performance characteristics on mobile phase organic content, pH, and buffer concentration is also reported.

Diflunisal ('Dolobid') once-a-day in the treatment of rheumatoid arthritis.

A 4-week, double-blind, controlled multi-centre study was carried out in 235 patients with active rheumatoid arthritis to compare the efficacy and tolerance of 500 mg or 1000 mg diflunisal per day administered once daily, in the evening, or in divided, twice daily dosage. The results showed that diflunisal given once daily was at least as effective as diflunisal given twice daily. Day pain, morning stiffness, average grip strength and erythrocyte sedimentation rate improved similarly in both groups. Significant differences favouring the once-daily regimen were observed for improvement in night pain, Ritchie index and overall assessments by patient and investigator. Adverse experiences were slightly more common in patients taking diflunisal once daily (24% vs 19%) but this difference was not significant. It is concluded, therefore, that diflunisal once-a-day is an alternative regimen for the treatment of rheumatoid arthritis. It is at least as effective as the twice-daily regimen and may provide additional convenience to the patient and potential enhancement of compliance.

HPLC analysis of thimerosal in ophthalmic solution. Comparing electrochemical with spectrophotometric detectors.

Electrochemical and spectrophotometric detectors for the reversed phase HPLC analysis of thimerosal in an ophthalmic formulation were evaluated with respect to response linearity, recovery, and lower limit of detection. The electrochemical oxidation of thimerosal at a glassy carbon electrode was characterized by both cyclic voltammetry and thin layer amperometry. The hydrodynamic half-wave potential for thimerosal (+0.6 V) was determined using a coulometric detector. The relatively low oxidation potential for thimerosal forms the basis for this highly sensitive and selective analytical technique. The amperometric lower limit of detection for thimerosal (at signal/noise = 2) was less than 400 pg. The detection limit with spectrophotometric detection at 254 nm was approximately 20 ng, a 50 fold increase.