Nematic-isotropic transition in a density-functional theory for hard spheroidal colloids.

We introduce a density-functional formalism based on the Parsons-Lee and the generalized van der Waals theories in order to describe the thermodynamics of anisotropic particle systems with steric interactions. For ellipsoids of revolution, the orientational distribution function is obtained by minimizing the free energy functional and the equations of state are determined. The system exhibits a nematic-isotropic discontinuous transition, characterized by a phase separation between nematic and isotropic phases at finite as well low packing fractions. The model presents a phase behavior which is in good agreement with Monte Carlo simulations for finite aspect ratios.

Nuclear organization and morphology of cholinergic neurons in the brain of the rock cavy (Kerodon rupestris) (Wied, 1820).

The aim of this study was to conduct cytoarchitectonic studies and choline acetyltransferase (ChAT) immunohistochemical analysis to delimit the cholinergic groups in the encephalon of the rock cavy (Kerodon rupestris), a crepuscular Caviidae rodent native to the Brazilian Northeast. Three young adult animals were anesthetized and transcardially perfused. The encephala were cut in the coronal plane using a cryostat. We obtained 6 series of 30-µm-thick sections. The sections from one series were subjected to Nissl staining. Those from another series were subjected to immunohistochemistry for the enzyme ChAT, which is used in acetylcholine synthesis, to visualize the different cholinergic neural centers of the rock cavy. The slides were analyzed using a light microscope and the results were documented by description and digital photomicrographs. ChAT-immunoreactive neurons were identified in the telencephalon (nucleus accumbens, caudate-putamen, globus pallidus, entopeduncular nucleus and ventral globus pallidus, olfactory tubercle and islands of Calleja, diagonal band of Broca nucleus, nucleus basalis, and medial septal nucleus), diencephalon (ventrolateral preoptic, hypothalamic ventrolateral, and medial habenular nuclei), and brainstem (parabigeminal, laterodorsal tegmental, and pedunculopontine tegmental nuclei). These findings are discussed through both a functional and phylogenetic perspective.

Effect of hop ß-acids as dietary supplement for broiler chickens on meat composition and redox stability.

Addition of ß-acids extracted from hop at different levels (0, 30mgkg-1, 60mgkg-1, 240mgkg-1) to the diet of broiler chickens demonstrated significant effects on the average concentration of polar metabolites and fatty acids of relevance for meat quality. The largest metabolic differences between control group and chicken fed different levels of ß-acids were achieved using 30mgkg-1 of supplement. As determined by EPR spin-trapping, increased redox stability was also obtained for meat from chicken fed 30mgkg-1 of ß-acids which also had highest level of endogenous antioxidants, especially anserine, carnosine, NADH and PUFAs. Diet and storage period were found to affect protein oxidation and myosin and actin were recognized as the main targets of protein oxidation. Myofibrillar proteins from chicken fed hop ß-acids showed to be less susceptible to oxidation. A moderated level of hop ß-acids as dietary supplement accordingly improve the overall redox stability, protecting myofibrillar proteins and fatty acids against oxidation and improve the nutritional properties of meat from broiler chickens.

Traceability from governmental producers of radiopharmaceuticals in measuring (18)F in Brazil.

Since the inception of its proficiency test program to evaluate radionuclide measurement in hospitals and clinics, the National Metrology Laboratory of Ionizing Radiation-LNMRI, that represents Brazilian National Metrology Institute (NMI) for ionizing radiation has expanded its measurement and calibration capability. Requirements from the National Health Surveillance Agency from Ministry of Health (ANVISA), to producers of radiopharmaceuticals provided an opportunity to improve the full traceability chain to the highest level. Fluorodeoxyglucose (FDG-(18)F) is the only radiopharmaceutical simultaneously produced by all Brazilian radiopharmaceutical production centers (RPCs). By running this proficiency test, LNMRI began to provide them with the required traceability. For evaluation, the ratio of RPC to reference value results and ISO/IEC17043:2010 criteria were used. The reference value established as calibration factor on the secondary standard ionization chamber was obtained from three absolute measurements systems, and routinely confirmed in each round of proficiency test by CIEMAT/NIST liquid scintillation counting. The γ-emitting impurities were checked using a High-Purity Germanium (HPGe) detector. The results show that Brazilian RPCs are in accordance with (accuracy within ±10%) the Brazilian standard for evaluation of measurements with radionuclide calibrators (CNEN NN 3.05., 2013). Nevertheless, the RPCs should improve the methodology of uncertainty estimates, essential when using the statistical criteria of ISO/IEC 17043 standard, in addition to improving accuracy to levels consistent with their position in the national traceability chain.

Astaxanthin diferulate as a bifunctional antioxidant.

Astaxanthin when esterified with ferulic acid is better singlet oxygen quencher with k2 = (1.58 ± 0.1) 10(10) L mol(-1)s(-1) in ethanol at 25°C compared with astaxanthin with k2 = (1.12 ± 0.01) 10(9) L mol(-1)s(-1). The ferulate moiety in the astaxanthin diester is a better radical scavenger than free ferulic acid as seen from the rate constant of scavenging of 1-hydroxyethyl radicals in ethanol at 25°C with a second-order rate constant of (1.68 ± 0.1) 10(8) L mol(-1)s(-1) compared with (1.60 ± 0.03) 10(7) L mol(-1)s(-1) for the astaxanthin:ferulic acid mixture, 1:2 equivalents. The mutual enhancement of antioxidant activity for the newly synthetized astaxanthin diferulate becoming a bifunctional antioxidant is rationalized according to a two-dimensional classification plot for electron donation and electron acceptance capability.

Maier-Saupe model for a mixture of uniaxial and biaxial molecules.

We introduce shape variations in a liquid-crystalline system by considering an elementary Maier-Saupe lattice model for a mixture of uniaxial and biaxial molecules. Shape variables are treated in the annealed (thermalized) limit. We analyze the thermodynamic properties of this system in terms of temperature T, concentration c of intrinsically biaxial molecules, and a parameter Δ associated with the degree of biaxiality of the molecules. At the mean-field level, we use standard techniques of statistical mechanics to draw global phase diagrams, which are shown to display a rich structure, including uniaxial and biaxial nematic phases, a reentrant ordered region, and many distinct multicritical points. Also, we use the formalism to write an expansion of the free energy in order to make contact with the Landau-de Gennes theory of nematic phase transitions.

Pharmacokinetics of tetracycline in plasma, synovial fluid and milk using single intravenous and single intravenous regional doses in dairy cattle with papillomatous digital dermatitis.

The purpose of this study was to compare the pharmacokinetics of tetracycline in plasma, synovial fluid, and milk following either a single systemic intravenous (i.v.) injection or a single i.v. regional antibiosis (IVRA) administration of tetracycline hydrochloride to dairy cattle with papillomatous digital dermatitis (PDD). To this end, plasma and synovial fluid tetracycline concentrations were compared with the minimal inhibitory concentration (MIC) values of the major bacteria, which are known to cause digital diseases and thus assess its efficacy in PDD. Residual tetracycline concentrations in milk from cows treated by both methods were also determined. Twelve Holstein cows with various stages of PDD were randomly assigned to two groups of six animals. Group 1 received a single systemic i.v. injection of 10 mg/kg of tetracycline hydrochloride. Group 2 received 1000 mg of tetracycline hydrochloride by IVRA of the affected limb. Blood, synovial fluid and milk samples were taken prior to tetracycline administration (time 0 control), and then at 22, 45 and 82 min, and 2, 3, 4, 6, 8, 12, 24, 48, 72, 96, and 120 h following drug administration. Tetracycline concentrations were determined by high-performance liquid chromatography. Mean tetracycline plasma and milk concentrations in Group 1 were higher than Group 2. The opposite was observed for synovial fluid concentrations. Group 2 synovial fluid concentrations were higher than the MIC value over 24 h for the bacteria most frequently responsible for claw disease. Compared with i.v. administration, IVRA administration of tetracycline produced very high synovial fluid and low plasma and milk concentrations.

Comparação entre as administrações tópica e sistêmica de oxitetraciclina no tratamento de vacas com dermatite digital papilomatosa / Efficacy of topical and systemic treatments with oxytetracycline for papillomatous digital dermatitis in cows

Comparou-se a eficiência dos tratamentos tópico e sistêmico com oxitetraciclina em vacas com dermatite digital papilomatosa (DDP) e determinaram-se a presença de resíduos desse antimicrobiano no leite e sua concentração no líquido sinovial e no plasma. Utilizaram-se o tratamento tópico com oxitetraciclina em pó (grupo 1) e o sistêmico de longa ação (grupo 2) em 16 vacas holandesas em lactação, acometidas por DDP. Obtiveram-se amostras de plasma, líquido sinovial e leite nos momentos: M0, antes dos tratamentos; M1, seis horas após o tratamento e em intervalos de 12 horas até M23 (264 horas pós-tratamentos). Avaliaram-se o grau de claudicação, a extensão da lesão e a concentração da oxitetraciclina pela cromatografia líquida de alta eficiência. Nas vacas do grupo 1, ocorreu redução das lesões e da claudicação, quando comparadas com as do grupo 2. Nenhuma das amostras de leite, de líquido sinovial e de plasma nos animais do grupo 1 foi positiva para oxitetraciclina. As amostras de leite dos animais do grupo 2, entre M1 e M23, apresentaram valores acima do limite máximo residual permitido para esse antimicrobiano. O tratamento tópico foi eficiente no tratamento de DDP, sem produzir resíduos no leite ou concentrações no plasma e no líquido sinovial. O tratamento sistêmico foi ineficiente para DDP, resultando em resíduos no leite, durante a avaliação.

The efficacy of topical versus systemic treatment with oxytetracycline for papillomatous digital dermatitis (PDD) in dairy cows was compared. Antimicrobial residues in milk and their concentrations in synovial fluid and plasma were analysed. Sixteen lactating Holstein cows with PDD lesions were topically treated with oxytetracycline powder (group 1) or long-acting oxytetracycline (group 2). Plasma, synovial fluid, and milk samples were collected in the following moments: M0 (before treatments); at six hours after treatments (M1), and at 12-hour intervals until 264 hours after treatments (M23). Lameness score and lesion size were evaluated. Analysis of oxytetracycline concentration was performed by high-performance liquid chromatography (HPLC). Cows in group 1 showed reduced lesion size and lameness score when compared to cows in group 2. None of the plasma, synovial fluid, or milk samples collected from cows in group 1 were positive to oxytetracycline. However, violative antimicrobial residues were detected in milk samples collected from cows in group 2, from M1 until M23. Topical application of oxytetracycline powder was an efficient treatment for PDD with no risk of violative antimicrobial residues in milk or increases its concentration in plasma or synovial fluid. The systemic administration of oxytetracycline was inefficient to treat PDD and caused violative residues in milk.

Calcium-binding proteins in the circadian centers of the common marmoset (Callithrix jacchus) and the rock cavy (Kerodon rupestris) brains.

The hypothalamic suprachiasmatic nucleus (SCN) and the thalamic intergeniculate leaflet (IGL) are considered to be the main centers of the mammalian circadian timing system. In primates, the IGL is included as part of the pregeniculate nucleus (PGN), a cell group located mediodorsally to the dorsal lateral geniculate nucleus. This work was carried out to comparatively evaluate the immunohistochemical expression of the calcium-binding proteins calbindin D-28k (CB), parvalbumin (PV), and calretinin (CR) into the circadian brain districts of the common marmoset and the rock cavy. In both species, although no fibers, terminals or perikarya showed PV-immunoreaction (IR) into the SCN, CB-IR perikarya labeling was detected throughout the SCN rostrocaudal extent, seeming to delimit its cytoarchitectonic borders. CR-IR perikarya and neuropil were noticed into the ventral and dorsal portions of the SCN, lacking immunoreactivity in the central core of the marmoset and filling the entire nucleus in the rock cavy. The PGN of the marmoset presented a significant number of CB-, PV-, and CR-IR perikarya throughout the nucleus. The IGL of the rocky cavy exhibited a prominent CB- and CR-IR neuropil, showing similarity to the pattern found in other rodents. By comparing with literature data from other mammals, the results of the present study suggest that CB, PV, and CR are differentially distributed into the SCN and IGL among species. They may act either in concert or in a complementary manner in the SCN and IGL, so as to participate in specific aspects of the circadian regulation.

Influence of temperature on microsporidia infections in a natural population of Simulium pertinax Kollar, 1832 (Diptera; Simuliidae).

During the studies involving the correlation between the water temperature of the breeding site of Simulium pertinax larvae and the infection prevalence by microsporidia, developed in the Andorinhas river, Magé, RJ, weekly samples of blackfly larvae were taken within a two-year period (2001-2002 and 2003-2004), and it was noticed that the infections by Amblyospora sp. were more prevalent when compared to infections by Polydispyrenia sp. in larvae. It was also observed that the infections do not follow the same pattern, since the genus Amblyospora was recorded almost every month during the study with the exception of December, 2001. In the results of correlation between the environmental water temperature and the microsporidia infection rates, it was observed that for the first period studied, there was a high negative correlation, while during the second period there was absence correlation. On the other hand, the Amblyospora sp. infection rates prove that the correlation was high and significant in the first period, but was not significant in the second sampling period and Polydispyrenia sp. showed absence correlation in both periods.

Influence of temperature on microsporidia infections in a natural population of Simulium pertinax Kollar, 1832 (Diptera; Simuliidae)

During the studies involving the correlation between the water temperature of the breeding site of Simulium pertinax larvae and the infection prevalence by microsporidia, developed in the Andorinhas river, Magé, RJ, weekly samples of blackfly larvae were taken within a two-year period (2001-2002 and 2003-2004), and it was noticed that the infections by Amblyospora sp. were more prevalent when compared to infections by Polydispyrenia sp. in larvae. It was also observed that the infections do not follow the same pattern, since the genus Amblyospora was recorded almost every month during the study with the exception of December, 2001. In the results of correlation between the environmental water temperature and the microsporidia infection rates, it was observed that for the first period studied, there was a high negative correlation, while during the second period there was absence correlation. On the other hand, the Amblyospora sp. infection rates prove that the correlation was high and significant in the first period, but was not significant in the second sampling period and Polydispyrenia sp. showed absence correlation in both periods.

Este estudo envolvendo a correlação entre a temperatura da água do criadouro de larvas de Simulium pertinax e a prevalência de infecção por microsporídeos, foi desenvolvido no rio Andorinhas, Magé, RJ, onde foram realizadas coletas semanais de larvas de simulídeos no período de dois anos (2001-2002 e 2003-2004), e foi observado que as infecções por Amblyospora sp. apresentaram maior prevalência quando comparadas com as infecções por Polydispyrenia sp. Com isso, verificou-se que as infecções não seguem o mesmo padrão, onde o gênero Amblyospora foi relatado em quase todos os meses de desenvolvimento do estudo, com exceção apenas de dezembro de 2001. Nos resultados de correlação entre a temperatura ambiente e a taxa de infecção por microsporídeos no primeiro período de estudo, foi observada uma forte correlação negativa, porém foi verificada ausência de correlação no segundo período. Embora tenha sido evidenciada uma forte e significante correlação com a taxa de infecção por Amblyospora sp. no primeiro período, esta correlação mostrou-se não significativa no segundo período de amostragem e Polydispyrenia sp. apresentou ausência de correlação em ambos os períodos de estudo.

[Trajectory and campaign of the Brazilian Nurses Association in Minas Gerais]. / Trajetória e luta da Associação Brasileira de Enfermagem em Minas Gerais.

The present article describes the trajectory, the work and the achievements of the Brazilian Association of Nursing (ABEn) in Minas Gerais. It describes some contributions of the association for the growth and development of the nursing profession in Minas Gerais and in the whole country. The facts and events reported in this investigation were taken from meeting minutes, newspaper articles, journals of the association, records and summaries of events, and oral interviews. The study initially outlines the origin of the association in Brazil, establishing connections with the foundation and development of ABEn Minas Gerais. It also describes the most important events, struggles and achievements promoted by the twenty-two administrations of the association, which consolidated ABEn-Minas Gerais. The conclusion of the study is that the solidification of this branch was achieved due to the effort and involvement of people who really valued and wanted to develop the nursing profession.

Methanol reference values in urine from inhabitants of Brazil.

In order to properly evaluate the results of the occupational biomonitoring of chemicals it is necessary to establish reference values for the biomarkers of exposure. The aim of this study was to determine the reference values for methanol in urine of the general population non-occupationally exposed to the xenobiotic under study. Thus, urinary methanol was measured in 84 occupationally non-exposed subjects from the city of São Paulo, Brazil, by means of headspace gas chromatography with a flame ionization detector. The results revealed a mean of 2.26 +/- 1.26 mg methanol/l urine and a geometric mean of 2.10 mg/l for the studied population. The reference values varied within the range of 0.50-4.78 mg/l (mean +/- 2 S.D.). Methanol levels in urine did not differ statistically between male and female subjects. Urinary methanol in the total population was less than 4.80 mg/l in 95% of cases.

[Biology of Methona themisto (Hübner, 1818) (Lepidoptera, Nymphalidae, Ithomiinae) adults in public plazas in Uberlândia, Minas Gerais, Brazil]. / Biologia dos adultos de Methona themisto (Hübner, 1818) (Lepidoptera, Nymphalidae, Ithomiinae) em praças públicas de Uberlândia, Minas Gerais, Brasil.

From April 1992 to September 1993 Methona themisto (Hübn.) adults were weekly marked and recaptured in two downtown plazas in Uberlândia, MG. Females accounted for a third of the 637 individuals marked. Nearly 10% of the butterflies were recaptured, with the maximum residence time of 62 days. The presence of the larval host plant (Brunfelsia uniflora (Pohl) D. Don, Solanaceae) in one of the plazas enhanced a higher abundance of the butterfly throughout the research and a higher proportion of new individuals, and frequency of migrants than the other plaza which lacked the host plant. Methona themisto adults were active through the sampling period with overlapping generations. Its abundance in plazas with polluted air and exotic flora, long adult life, and tolerance to humans in its vicinities place M. themisto among the ones indicated to have its life conditions improved in downtown areas of brazilian cities. Simple managing practices which benefit the lepitopteran are suggested.

[The nursing school of the Federal University of Minas Gerais: from its creation until today]. / A escola de enfermagem da UFMG: da criação aos dias atuais.

The purpose of this work was to bring back some historical aspects of the Federal University of Minas Gerais Nursing School--EEUFMG, since its creation in 1933 until 1998.

Determination of synthetic estrogens in illegal veterinary formulations by HPTLC and HPLC.

To determine the actual amount of diethylstilbestrol, hexestrol, and dienestrol in formulations such as pellets and oily injections that are illegally available on the Brazilian market, a simple methanol extraction is used for the analysis of the pellets and an ether extraction with Sephadex columns (for clean-up) is used for the oily injections. High-performance thin-layer chromatography is used for identification (as a qualitative and semiquantitative method), and high-performance liquid chromatography is used for quantitation. The results of the analysis show that all the formulations are not in accordance with the information listed on their labels.

Determination of xanthines by high-performance liquid chromatography and thin-layer chromatography in horse urine after ingestion of Guaraná powder.

The seeds of Guaraná are rich in xanthines and are used for the preparation of guaraná powder which is very commonly given to horses as a 'tonic' in Brazil. In this paper, the xanthine content of guaraná powder was determined, in addition to its clearance time in horses. Thin-layer chromatography was used as a screening procedure and high-performance liquid chromatography was performed to quantify the drugs in both the powder and urine samples. The guaraná powder was found to contain 2.16, 1.10 and 36.78 mg g-1 of theobromine (TB), theophylline (TP) and caffeine (CF), respectively, and in urine it was possible to detect TB and TP up to 13 d and CF up to 9 d after the administration of guaraná powder.