Traceability of animal meals in Japanese quail eggs using the technique of 13C e 15N* stable isotopes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fighting by sleep-deprived rats as a possible manifestation of panic: effects of sodium lactate

Increased fighting is an effect of desynchronized sleep deprivation (DSD) in rats, and recently this behavior has been suggested to be spontaneous panic and equivalent to panic disorder. In the present study we tested this hypothesis by evaluating the effect of sodium lactate on this aggressiveness, because this substance is recognized to induce spontaneous panic attacks in patients. A total of 186 male albino Wistar rats, 250-350 g, 90-120 days of age, were submitted to DSD (multiple platform method) for 0, 4, or 5 days. At the end of the deprivation period the rats were divided into subgroups respectively injected intraperitoneally with 1.86, 2.98 and 3.72 g/kg of 1 M sodium lactate, or 1.86 and 3.72 g/kg of 2 M sodium lactate. The control animals were submitted to the same procedures but received equivalent injections of sodium chloride. Regardless of DSD time, sleep-deprived animals that received sodium lactate presented a significantly higher mean number of fights (0.13 ± 0.02 fights/min) and a longer mean time spent in confrontation (2.43 ± 0.66 s/min) than the controls (0.01 ± 0.006 fights/min and 0.12 ± 0.07 s/min, respectively; P<0.01, Student t-test). For the sodium lactate group, concentration of the solution and time of deprivation increased the number of fights, with the mean number of fights and mean duration of fighting episodes being greater with the 2.98 g/kg dose using 1 M lactate concentration. These results support the hypothesis that fighting induced by DSD is probably a spontaneous panic manifestation. However, additional investigations are necessary in order to accept this as a promising animal model for studies on panic disorder.

Riscos para o excesso de peso entre adolescentes de diferentes classes socioeconômicas

OBJETIVO: Analisar a associação entre fatores de risco e a presença do excesso de peso entre adolescentes de diferentes classes socioeconômicas. MÉTODOS: Análise transversal, da qual participaram 888 jovens de ambos os sexos e com idade variando entre 11 e 17 anos. O índice de massa corporal foi calculado por meio dos valores de massa corporal e estatura, e utilizado como indicador do excesso de peso. A atividade física, a ingestão alimentar e a classe socioeconômica (alta e baixa) foram analisadas mediante a aplicação de questionários. Os dados foram analisados estatiscamente por meio dos testes Qui quadrado e regressão logística binária. RESULTADOS: Para os adolescentes de classe socioeconômica baixa, uma inadequada ingestão alimentar (Razão de chance [RC]= 4,59) e o sobrepeso dos pais (RC= 5,33) foram associados à presença do excesso de peso. Entre os adolescentes de classe socioeconômica alta, a escolaridade materna (RC= 0,57), estudar em escola privada (RC= 3,04) e o sobrepeso dos pais (RC= 3,47) foram associados à presença do excesso de peso. CONCLUSÃO: em ambas as classes socioeconômicas, o sobrepeso dos pais foi um importante fator de risco associado ao excesso de peso. Os outros fatores de risco diferiram entre as classes socioeconômicas.

Ocorrência de infecção hospitalar em idosos internados em hospital universitário

OBJETIVO: A infecção hospitalar é uma importante causa de morbidade e mortalidade na população idosa. O estudo realizado teve como objetivo avaliar a ocorrência e os fatores de risco da infecção hospitalar. MÉTODOS: Realizou-se estudo prospectivo em uma amostra de 322 idosos com 60 anos e mais, internados em um hospital universitário, entre setembro de 1999 e fevereiro de 2000. O cálculo da amostra foi feito pela fórmula de Fisher e Belle, com intervalo de confiança de 0,95%, de um total de 760 idosos internados, proporcionalmente ao número de pacientes em cada unidade de internação, no ano de 1997. Os critérios para definição da infecção hospitalar foram os do Center for Diseases and Prevention Control. Para a análise estatística dos dados foram utilizados o odds ratio e regressão logística. RESULTADOS: A taxa de infecção hospitalar encontrada foi de 23,6%. As topografias prevalentes de infecção hospitalar foram infecção respiratória (27,6%), do trato urinário (26,4%) e do sítio cirúrgico (23,6%). O tempo de internação dos pacientes sem infecção hospitalar foi de 6,9 dias e dos com infecção hospitalar foi de 15,9 (p<0,05). A taxa de mortalidade dos pacientes internados foi de 9,6% e a de letalidade dos pacientes com infecção hospitalar de 22,9% (p<0,05). Os fatores de risco encontrados para infecção hospitalar foram colangiografia (odds ratio (OR)=46,4, intervalo de confiança 95% (IC 95%)=4,4-485); diabetes melito (OR=9,9, IC 95%=4,4-22,3); doença pulmonar obstrutiva crônica (OR=8,3, IC 95%=2,9-23,7); cateterismo urinário (OR=5, IC 95%=2,7-11,8); internação com infecção comunitária (OR=3,9, IC 95%=1,7-8,9) e ventilação mecânica (OR=3,8, IC 95%=1,9-6,3). CONCLUSÕES: A infecção hospitalar apresentou incidência e letalidade elevadas e aumentou o tempo de internação dos idosos estudados.

Case-case-control study of risk factors for nasopharyngeal colonization with methicillin-resistant Staphylococcus aureus in a medical-surgical intensive care unit

Nasopharyngeal colonization with methicillin-resistant Staphylococcus aureus (MRSA) often precedes the development of nosocomial infections. In order to identify risk factors for MRSA colonization, we conducted a case-case-control study, enrolling 122 patients admitted to a medical-surgical intensive care unit (ICU). All patients had been screened for nasopharyngeal colonization with S. aureus upon admission and weekly thereafter. Two case-control studies were performed, using as cases patients who acquired colonization with MRSA and methicillin-susceptible S. aureus (MSSA), respectively. For both studies, patients in whom colonization was not detected during ICU stay were selected as control subjects. Several potential risk factors were assessed in univariate and multivariable (logistic regression) analysis. MRSA and MSSA were recovered from nasopharyngeal samples from 27 and 10 patients, respectively. Independent risk factors for MRSA colonization were: length-of-stay in the ICU (Odds Ratio [OR]=1.12, 95%Confidence Interval[CI]=1.06-1.19, p<0.001) and use of ciprofloxacin (OR=5.05, 95%CI=1.38-21.90, p=0.015). The use of levofloxacin had a protective effect (OR=0.08, 95%CI=0.01-0.55, p=0.01). Colonization with MSSA was positively associated with central nervous system disease (OR=7.45, 95%CI=1.33-41.74, p=0.02) and negatively associated with age (OR=0.94, 95%CI=0.90-0.99, p=0.01). In conclusion, our study suggests a role for both cross-transmission and selective pressure of antimicrobials in the spread of MRSA.

Composição química do capim-elefante cv. Roxo cortado em diferentes alturas

O objetivo deste trabalho foi verificar o efeito dos cortes efetuados a 0, 15, 30 e 45 cm sobre a composição química do capim-elefante (Pennisetum purpureum, Schum.) cv. Roxo, em épocas seca e chuvosa. As amostras foram obtidas de uma área útil de 8,4 m² de cada parcela. Após o corte de uniformização, efetuaram-se dois cortes no período seco, em intervalos de 90 dias, e três no período chuvoso, em intervalos de 60 dias. de cada parcela foi tomada uma amostra de 3 a 5 perfilhos, desidratada em estufa e triturada para analises laboratoriais. Foram avaliados os percentuais de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), celulose (CEL), hemicelulose (HCEL), lignina (LIG) e cinzas. As alturas de corte não influenciaram a composição química da forrageira, nem houve interação com as épocas. Com exceção de hemicelulose e cinzas, os cortes na época seca mostraram resultados superiores à chuvosa. As médias nas duas épocas foram 19,70 e 17,44% para MS; 7,74 e 7,25% para PB; 76,41 e 71,13% para FDN; 42,75 e 41,02% para FDA; 31,44 e 30,43% para CEL; 30,66 e 30,28% para HCEL; 9,25 e 7,83% para LIG; e 1,97 e 3,38% para cinzas, nos períodos seco e chuvoso, respectivamente.

Perfilhamento e algumas características morfológicas do capim-elefante cv. Roxo sob quatro alturas de corte em duas épocas do ano

O objetivo deste trabalho foi verificar o efeito dos cortes efetuados a 0, 15, 30 e 45 cm sobre algumas características morfofisiológicas do Pennisetum purpureum, Schum. cv. Roxo nas épocas seca e chuvosa no Brejo Paraibano. As amostras foram obtidas de uma área útil de 8,4 m² de cada parcela. Após o corte de uniformização, efetuaram-se dois cortes no período seco, em intervalos de 90 dias, e três no período chuvoso, em intervalos de 60 dias. Foram avaliados os seguintes parâmetros: perfilhamento, altura das plantas, porcentagens de folhas e colmos e relação folha/colmo (RF/C). Aos 25 dias após cada corte, foram feitas as contagens dos perfilhos existentes nas parcelas. de cada parcela tomou-se uma amostra de 3 a 5 perfilhos, seca em estufa, e separaram-se as frações de folhas e colmos. Houve interação dos fatores (altura x época do corte) quanto ao número de perfilhos por m² e à RF/C. No período chuvoso, houve mais perfilhos basais que no período seco, e o número de perfilhos aéreo foi superior em todos os cortes acima do nível do solo. A RF/C foi superior na época chuvosa nas alturas de 30 e 45 cm do solo. Cortes mais altos apresentaram maior proporção de folhas e menor proporção de colmos. Os percentuais de folhas na época chuvosa foram maiores que os da época seca.

Chemical treatment of post-harvest Marandu grass seed residues with different moisture contents

Objetivou-se avaliar o efeito do tratamento químico com ureia (3 ou 5% na MS) e amônia anidra (3% na MS) no feno de resíduo pós-colheita de sementes de Brachiaria brizantha, cv. Marandu, contendo diferentes teores de umidade (15, 25 ou 30%). O delineamento experimental foi em blocos ao acaso com oito tratamentos e quatro repetições (camadas de fardos dentro das pilhas). O feno tratado com 3% de amônia anidra com 15% de umidade ocasionou redução de 84,3 para 79,1% nos teores de fibra em detergente neutro (FDN) e elevação de 37,3 para 55,5% na digestibilidade in vitro da matéria seca (MS) em relação ao grupo controle. A variação na umidade não alterou de maneira significativa a ação da amônia, cujos valores médios foram 77,6% de FDN e 57,3% de digestibilidade in vitro da MS. O feno com 5% de ureia reduziu os teores de FDN de 84,3 para 79,6% em relação ao feno não-tratado, o que tornou necessário o aumento da umidade para 30% para maior efeito sobre a digestibilidade da MS, que aumentou 12 unidades percentuais.

Anxiolytic-like effects of median raphe nucleus lesion in the elevated T-maze

The cell bodies of 5-HT containing neurons that innervate the limbic forebrain are mainly found in the dorsal raphe nucleus and in the median raphe nucleus (MRN). To assess the role of the median raphe nucleus in anxiety, rats bearing either electrolytic or 5-HT-selective neurotoxic lesion of the MRN were tested in the elevated T-maze. This apparatus consists of two opposed open arms perpendicular to one enclosed arm. Two tasks are performed in succession by the same rat in one experimental session, namely inhibitory avoidance of the open arm, taken as a measure of conditioned anxiety and one-way escape from the open arm, considered as a measure of unconditioned fear. The test was performed 7 days after the electrolytic lesion (3 mA, 10 s) or 14 days after the neurotoxic lesion (5,7-DHT, 8 mug/1 mul). The results showed that while the electrolytic lesion impaired both inhibitory avoidance and one-way escape, the neurotoxic lesion impaired only inhibitory avoidance. Therefore, serotonergic pathways originating in the MRN seem to participate in the modulation of conditioned anxiety but not unconditioned fear. Other neurotransmitter systems that either originate in or pass through the MRN may regulate unconditioned fear. (C) 2003 Elsevier B.V. All rights reserved.

Serotonergic mechanisms of the lateral parabrachial nucleus in renal and hormonal responses to isotonic blood volume expansion

This study investigated the involvement of serotonergic mechanisms of the lateral parabrachial nucleus (LPBN) in the control of sodium (Na+) excretion, potassium (K+) excretion, and urinary volume in unanesthetized rats subjected to acute isotonic blood volume expansion (0.15 M NaCl, 2 ml/100 g of body wt over 1 min) or control rats. Plasma oxytocin (OT), vasopressin (VP), and atrial natriuretic peptide (ANP) levels were also determined in the same protocol. Male Wistar rats with stainless steel cannulas implanted bilaterally into the LPBN were used. In rats treated with vehicle in the LPBN, blood volume expansion increased urinary volume, Na+ and K+ excretion, and also plasma ANP and OT. Bilateral injections of serotonergic receptor antagonist methysergide (1 or 4 mu g/200 eta 1) into the LPBN reduced the effects of blood volume expansion on increased Na+ and K+ excretion and urinary volume, while LPBN injections of serotonergic 5-HT2a/HT2c receptor agonist, 2.5-dimetoxi-4-iodoamphetamine hydrobromide (DOI;1 or 5 mu g/200 eta 1) enhanced the effects of blood volume expansion on Na+ and K+ excretion and urinary volume. Methysergide (4 mu g) into the LPBN decreased the effects of blood volume expansion on plasma ANP and OT, while DOI (5 mu g) increased them. The present results suggest the involvement of LPBN serotonergic mechanisms in the regulation of urinary sodium, potassium and water excretion, and hormonal responses to acute isotonic blood volume expansion.

Different methods of finishing and polishing enamel

Statement of problem. Highly polished enamel surfaces arc recommended for axial tooth surfaces that will serve as guiding planes and be contacted by component parts of a removable partial denture. There is little evidence to support the assumption that this tooth modification will provide accurate adaptation of the framework and prevent build-up of plaque.Purpose. The aim of this investigation was to evaluate the surface roughness of the tooth enamel, prepared to serve as guiding planes, with different polishing systems.Material and methods. Four different methods (designated A, B, C, and D) for finishing and polishing the prepared enamel surfaces of 20 freshly extracted third molar teeth were studied. Each method involved 3, 4, or 5 different steps. The roughness of each specimen was measured at the start of each method before recontouring, after recontouring, and after each step of the 4 finishing and polishing procedures. The 4 experimental finishing methods were applied after recontouring the axial surfaces (buccal, lingual, and proxinial) of each tooth. Thus the 20 teeth (60 surfaces) were finished and polished by use of 1 of the experimental methods. Surface roughness was measured with a profilometer (mum); the readings of the unpolished enamel Surfaces were recorded as control measurements. Results were statistically analyzed with one-way analysis of variance followed by Tukey's test at the 95% level of confidence.Results. The highest roughness mean values (14.41 mum to 16.44 mum) were found when the diamond bur was used at a high speed for tooth preparation. A significant decrease in roughness values was observed with the diamond bur at a low speed (P<.05). Analysis of the roughness values revealed that all polishing methods produced surface roughness similar to that of the corresponding control teeth.Conclusion. Within the limitations of this study, all finishing procedures tested effectively promoted an enamel surface similar to the original unpolished enamel.

Influence of management and environmental factors on mating success of Africanized queen honey bees

Environmental factors and management techniques were evaluated in São Paulo, Brazil, for enhanced production of Africanized queen honey bees. Queens were reared by the Doolittle method; 12 breeder, 6 cell-builder, and 36 3-frame nucleus colonies were used. Nine groups of four virgin Africanized queen honey bees were subjected to the following treatments: queens were either 1-2, 3-4 or 5-6 days old and were released into mating nuclei containing either capped brood, uncapped brood or no brood. This was repeated sixteen times between August 1990 and August 1992. Seven repetitions occurred during nectar flow periods and nine repetitions occurred during nectar-dearth periods. Overall, 59% of 576 queens were successfully introduced and mated. The best results (93% success) were obtained during nectar flows, with 3- to 4-day-old queens released into nuclei containing capped brood. During nectar dearths the best mating success came from queens introduced into broodless nuclei (63%), the age of the queen did not influence mating success. Mating success decreased when wind velocity increased; this was the only significant meteorological effect found.

In vitro evaluation of acidified toothpastes with low fluoride content

Fluoride toothpastes are a risk factor for the development of dental fluorosis. Products with low fluoride content offer a higher security, but their effectiveness must be proven. The aim of this in vitro study was to compare two acidified toothpastes with low fluoride concentration (412 and 550 mu g F/g) with neutral toothpastes. Bovine enamel blocks were selected by surface microhardness (SMH) and randomized to twelve groups of 13, according to the fluoride concentration in toothpaste (placebo, 275, 412, 550 or 1,100 jig F/g) and pH (7.0 or 5.5). Two commercially available toothpastes were also studied: a 1,100-mu g F/g, pH 7.0 paste (positive control) and a children's paste (500 mu g F/g, pH 7.0). The blocks were subjected to pH cycling for 7 days. The toothpaste treatment was done twice daily. Surface and cross-sectional microhardnesses were assessed to calculate the percentage change of SMH (%SMH) and the mineral loss (Delta Z). The amount of fluoride, calcium and phosphorus in the solutions after the pH cycling was also analyzed. Compared to neutral toothpastes, the acidified toothpastes reduced the %SMH in all F concentrations. Higher F and lower Ca and P concentrations were found in solutions for the acidified toothpastes. Regarding AZ, only the positive control, 1,100-mu g F/g (acidified and neutral) groups were not statistically different. The acidified toothpastes showed a dose-response relationship with all variables. For the low-fluoride toothpastes evaluated, only the 550-mu g F/g acidified paste had the same anticariogenic action as the 1,100-mu g F/g neutral paste.

Influence of ceramic surface conditioning and resin cements on microtensile bond strength to a glass ceramic

Statement of problem. It is not clear how different glass ceramic surface pretreatments influence the bonding capacity of various luting agents to these surfaces.Purpose. The purpose of this study was to evaluate the microtensile bond strength (mu TBS) of 3 resin cements to a lithia disilicate-based ceramic submitted to 2 surface conditioning treatments.Material and methods. Eighteen 5 X 6 X 8-mm ceramic (IPS Empress 2) blocks were fabricated according to manufacturer's instructions and duplicated in composite resin (Tetric Ceram). Ceramic blocks were polished and divided into 2 groups (n=9/treatment): no conditioning (no-conditioning/control), or 5% hydrofluoric acid etching for 20 seconds and silanization for 1 minute (HF + SIL). Ceramic blocks were cemented to the composite resin blocks with I self-adhesive universal resin cement (RelyX Unicem) or 1 of 2 resin-based luting agents (Multilink or Panavia F), according to the manufacturer's instructions. The composite resin-ceramic blocks were stored in humidity at 37 degrees C for 7 days and serially sectioned to produce 25 beam specimens per group with a 1.0-mm(2) cross-sectional area. Specimens were thermal cycled (5000 cycles, 5 degrees C-55 degrees C) and tested in tension at 1 mm/min. Microtensile bond strength data (MPa) were analyzed by 2-way analysis of variance and Tukey multiple comparisons tests (alpha=.05). Fractured specimens were examined with a stereomicroscope (X40) and classified as adhesive, mixed, or cohesive.Results. The surface conditioning factor was significant (HF+SIL > no-conditioning) (P<.0001). Considering the unconditioned groups, the mu TBS of RelyX Unicem was significantly higher (9.6 +/- 1.9) than that of Multilink (6.2 +/- 1.2) and Panavia F (7.4 +/- 1.9). Previous etching and silanization yielded statistically higher mu TBS values for RelyX Unicem (18.8 +/- 3.5) and Multilink (17.4 +/- 3.0) when compared to Panavia F (15.7 +/- 3.8). Spontaneous debonding after thermal cycling was detected when luting agents were applied to untreated ceramic surfaces.Conclusion. Etching and silanization treatments appear to be crucial for resin bonding to a lithia disilicate-based ceramic, regardless of the resin cement used.

Infecção experimental pelo Encephalitozoon cuniculi em camundongos imunossuprimidos com dexametasona

Objective Microsporidian Encephalitozoon cuniculi has been recognized as an opportunistic pathogen in immunosuppressed individuals, such as AIDS patients. The objective of the study was to develop pharmacologically immunosuppressed animals as a model of the natural occurring E. cuniculi infection.Methods Distint groups of adult Balb-C mice were immunosuppressed with different doses of dexamethasone (Dx, 3 or 5 mg/kg/day, intraperitoneal route - IP) and inoculated with E. cuniculi spores by IP route intraperitoneally. Control groups (inoculated animals but non-immunosuppressed and non-inoculated animals but immunosuppressed) were also used. The spores of E. cuniculi were previously cultivated in MDCK cells. The animals were sacrificed and necropsied at 7, 14, 21, 28 and 35 days post-inoculation. Tissue fragments were collected and processed for light microscopy studies, using Gram-chromotrope and hematoxylin-eosin staining techniques.Results In all immunosupressed and inoculated inoculated immunosuppressed mice,specially in those that received 5 mg/kg/day of dexamethasone, the most prominent necropsy findings were hepatomegaly and splenomegaly. The experimental inoculation resulted in a disseminated non-lethal infection, characterized by granulomatous lesions in several organs (liver lungs, kidneys, gut and brain) but notably in the hepatic tissue. Spores of E. cuniculi were only seen in few animals treated with 5 mg/kg/day of Dx at 35 days post-infection.Conclusions Microsporidiosis in Dx-immunosuppressed mice provides a useful model for studies of the microsporidial infection, resembling that one naturally occurring in immunodeficient individuals with AIDS.