Avaliação da expressão imuno-histoquímica de marcadores de hipóxia em carcinoma epidermóide de língua

The tumor hypoxia modulates a series of genetic changes related to adaptive development, invasion and metastasis of various human cancers, among which squamous cell carcinoma of the tongue (SCCT). The objective of this study was to analyze clinical, morphological and immunohistochemical expression by HIF-1α, GLUT-1 and CA-IX in 57 cases of CEL and correlated this expression to clinical parameters and morphological. After a descriptive analysis of data on gender, age, race, and habits of patients, it was found that the results were consistent with the literature. The clinical and morphological parameters analyzed and the expression of these markers of hypoxia were subjected to statistical analysis (Qui2 test), verifying that they can be used as indicators of the biological behavior of CEL. Among the results of this study, we observed that the intensity of expression for HIF-1α, in most cases located in the cytoplasm and nucleus, statistically correlated with clinical staging (p = 0.011) and histological grading (p = 0.002). As for the relationship between the distribution of labeling for HIF-1α and metastasis, the chi-square (Qui2) showed that there was statistically significant differences between the groups (p = 0.040). 75.8% of the sample who had metastases, there was the predominance of diffuse marking. The immunoexpression cytoplasmic/membrane GLUT-1 showed a statistically significant correlation with the clinical stage (p = 0.002) and histological grading (p = 0.000). Concerning the location of markings for GLUT-1 tumor on the island, there was a predominance of peripheral marking specimens in most low-grade (78.6%). In the sample of high-grade, prevailed the location center/periphery (55.8%). According to the chi-square (Qui2), the location on the island of the tumor (p = 0.025) showed statistically significant difference in histological grading. The immunoreactivity of CA-IX, in most cases located in the membrane and cytoplasm, exhibited a statistically significant correlation with histological grading (p = 0.005). Based on these results, we can conclude a broad participation of these markers of hypoxia in oral carcinogenesis and its possible use as markers of biological behavior and tumor progression in CEL

Expressão imuno-histoquímica das integrinas α2ß1, α3ß1, e α5ß1, em mucosa oral normal, hiperplasia fibroepitelial inflamatória oral e displasia epitelial oral

The objective of this study was perform by the streptoavidin-biotin technique an immunohistochemical analysis of α2β1, α3β1e α5β1 integrins in 11 normal oral mucosa (NOM), 16 oral inflammatory fibroepithelial hyperplasia (OIFH) and 25 oral epithelial dysplasia (OED) (16 mild, 2 moderates and 7 severe), to determine if exists qualitative alteration in the expression of these integrins and if this guard relation with the oral epithelial modifications. It was observed that for the α2β1 integrin the majority of the sample showed a predominantly intense labeling diffusely distributed in the intercellular contacts and the cytoplasm of cells of the basal and suprabasal layers, without difference of this profile between the different types of specimens, however with a trend to weak or loss of expression in 21.1% of the OEDs, being all the specimens that had not expressed this heterodimer, severe OEDs. For the α3β1 integrin the majority of the sample showed a weak or absent labeling in basal layer. The α5β1 integrin showed a predominant strong diffuse labeling in the intercellular contacts and cytoplasm in the suprabasal layer, with difference only in the labeling intensity between the types of specimens, inhabiting this difference in the OEDs, where 12 (48%) specimens had shown a weak labeling. It was concluded that the evaluated integrins can be involved in the cell-cell, cell-ECM interactions modulating the cellular differentiation and maintenance of the epithelial structural arrangement. The variable expression of the α5β1 integrin in the OEDs, could suggest, respectively, a role of this molecule in the cellular survival, with intention to perpetuate the modified phenotype in these lesions, or a suppressor role on the modified phenotype due to lack of interaction of this molecule with the fibronectina of the MEC

Expressão imuno-histoquímica das integrinas α2ß1, α3ß, e α5ß1, em carcinoma epidermóide de lábio inferior e língua

The unpredictable biologic behavior of the oral squamous cells carcinoma has determined extensive research on the evolution of such tumor. Due to the existing relation between the outer cell matrix and the tumor cells, the integrins have been used as markers in the predictive study of the cell behavior. This study aims to analyze immunohistochemically the expression of the integrin α2β1, α3β1, and α5β1 connections for the collagen, the laminin and the fibronectin respectively in 15 cases of squamous cells carcinoma from the lower lip and 15 from the tongue, with different scores of malignance grading. A predominantly diffuse, cytoplasm and granular immunological marking was observed in the majority of the analyzed cases. According to the marking intensity, integrin α2β1 appeared positive in 80% of the lip and in 93,3% of the tongue cases. The immunological reactivity of integrin α3β1 was classified as positive in 60% of both the tongue and lip cases. For this integrin, 20% and 33.3% of the tongue and lip cases, respectively, were negative. In relation to integrin α5β1 the intensity was classified as positive in 53,3% of the cases and strongly positive in 46,7% of those located in the lip. In the tongue carcinomas, the intensity was positive in 46,7% of the cases and strongly positive in 53,3%. The statistic analysis did not show any significant differences or correlation of expression between these integrins nor between the anatomical sites or between different scores of malignancy grading. The expressive immunological marking of the integrins, α2β1, α3β1, and α5β1 in the studied cases of squamous cell carcinomas leads us to think of a great participation of these proteins in oral carcinogenesis; however, our results do not allow us to correlate its expression as an indicator of variations in the biological behavior of this neoplasia

Interações físicas e psicossociais em mulheres com fibromialgia

Fibromyalgia (FM) is a non-inflammatory rheumatic syndrome of unknown etiology, with symptoms of diffuse musculoskeletal pain and presence of specific anatomic sites called tender points. The symptoms are often associated with fatigue, sleep disturbances, morning stiffness, alterations in pain perception, anxiety and depression. Fibromyalgia exhibits a correlation between physical and behavioral symptoms, which have a negative influence on the quality of life of patients. Emotional skills are important factors since they are related to subjective well-being, personal productivity, social interaction and interpersonal relationships. We aim to describe the physical and psychosocial interactions in women with FM, showing the association between perceived social support and affect with symptoms of pain, functionality and mood. We will also describe a body representation of pain in women with FM. Data were collected over 3 years and the sample size ranged between studies. This is an exploratory cross-sectional study conducted with a convenience sample of 63 women with FM and 42 healthy women as a control group (CT), aged 20-76 years, recruited through spontaneous demand at Onofre Lopes University Hospital (HUOL) and the Clinical School of Physiotherapy of Universidade Potiguar (UNP). The Fibromyalgia Impact Questionnaire (FIQ), Beck Depression Inventory (BDI), Social Support Scale (MOS), Hamilton Anxiety Scale and Scale of Positive and Negative Affect Schedule (PANAS), in addition to pressure algometry were used. For data analysis, we used parametric and non-parametric tests and a general linear model with adjustment variables and analysis of variance. A significant difference was found between pain threshold and tolerance, functionality, depression, anxiety, social support, and positive and negative affect between the groups. Affective states and social support were associated with anxiety, depression and functionality. A body was drawn representing pain with higher incidences in trapeze, supraspinatus and second ribs. The reason for studying sensory aspects, affective behavior and social support in FM patients opens perspectives for scientific and clinical research of this syndrome. Women with chronic pain such as FM appear to have altered mood states, less social support and affective dysfunctions, influencing the other symptoms of the syndrome

Boto cinza (Sotalia guianensis, Van Benédén, 1864) (Cetacea, Delphinidae): Atividade aérea, forrageio e interações inter-específicas, na Praia de Pipa (Tibau do Sul RN) e estudo comparativo entre duas populações do Nordeste do Brasil

Sotalia guianensis is a small cetacean of the Delphinidae family, with coastal habits and whose area of distribution ranges from Florianópolis (27º35'S, 48º34'W), in Brazil, to Honduras (15º58'N, 85º42'W). At Pipa beach, on the south coast of RN state, in Brazil, the species occur throughout the year. The present study was carried out in two bays, which are bordered by cliffs. The animals were monitored from vantage points, using the "Ad libitum" and "all the occurrences" methods; during the years of 1999 and 2004. The study was divided in 4 chapters: Behavioral standards of two populations of gray dolphin, (Sotalia guianensis, Van Benédén, 1864) in the northeast of Brazil; Aerial activity of the gray dolphin: its possible function and the influence of environmental and behavioral factors; The influence of daily and monthly variation of the tides, of the period of the day and group size on the gray dolphin forage activity; kleptoparasitism interactions of frigatebird (Fregata magnificens, Mattheus, 1914) during the gray dolphin forage activity. The results have shown that the gray dolphin has a varied and complex behavioral repertoire. The leap is the most frequent behavior; the aerial activity is diffuse during daylight and is influenced by some factors, such as the level of the tide and social factors. The gray dolphin, when in the bay, most frequently feeds isolate or in small groups. The forage is diffuse during daylight; however, being more frequent in the morning and is influenced by the daily and monthly variation of the tide. At Pipa beach, kleptoparasitarian interactions were registered between the gray dolphin and the frigatebird (Fregata magnificens). The frigatebird forage strategy consists basically of two ways: to fly over great extensions searching for dead fish and to steal food (kleptoparasitism). These interactions were predominantly carried out between immature and female adult birds and adult and immature dolphins, and occurred during daylight. The present study can be considered an initial landmark to a better knowledge on the gray dolphin surface behavior, especially regarding the aerial behavioral repertoire and forage strategy of this species. However, it is necessary to continue these studies, so that we can understand better the complex social life of these animals and thus create effective measures for its conservation

Preferências e escolhas românticas entre universitários

Several studies have found different patterns of preferences to men and women for short term and long term relationship romantic partners. It is known that the preferences vary with the sex of individuals, the expected involvement level of the relationship and according to the perceptions that subjects have about themselves. In the present study, we investigate whether the preferences typically founded for sexes are also founded between Brazilian undergraduate students. We also investigated if the individuals choose partners in accord of the sex preferences and if the ideal preferences are really expressed in real choices. For these investigations, 370 undergraduate students described profiles of an ideal partner for a short-term and a long-term relationship, through the joint evaluation of nine characteristics. Each ideal s profile has been described over three simulations, in which the amount of points available to be invested were limited and gradually reduced. After the descriptions of these profiles, the participants described the current or previous partner (if they were not in a relationship) and performed a self-assessment with the same characteristics used in the description of preferences. Overall, the results obtained in several countries were observed in Brazil. For short-term relationships men prioritize physical attributes and women value physical and personal attributes. For long-term, personal traits gained in importance on masculine preferences and women emphasized personal traits and the partner disposition to acquire resources. We also identified similar preferences profiles for both sexes and that the romantic preferences reflect similarities with the own individual s characteristics, in addition to the typical sexual preferences expected for the Parental Investment Theory. When evaluated their real partners, men considerate them more physically attractive than themselves but less intelligent, good humorous and ambi tion/willing to work. Women, in turn, described their partners as good as them. Finally, we observed equivalence between characteristics of the subjects and those of its partners, this effect being more pronounced among men. The last partners were described only as less sincere. The interpretation of the most part of our results was possible from evolutionist s and socio-cultural s explanations and was discussed under the two perspectives. We conclude this study stressing that the traditional romantic preferences occur in Brazil and that the sex, the kind of relationship and the vision that people have about their own characteristics affect the preferences, which are expressed in the real partner choices

Avaliação do cortisol, dehidroepiandrosterona sulfato e dos perfis lipídico e imunológico e suas correlações com a sensibilidade dolorosa, depressão e funcionalidade em mulheres com fibromialgia na pós-menopausa

Fibromyalgia (FM) is a non-inflammatory rheumatic syndrome characterized by widespread musculoskeletal pain with palpable tender points, muscle stiffness, fatigue, and sleep disturbances. Patients with FM have hormonal changes that are directly correlated with symptoms of the syndrome. The neuroendocrine regulation may be impaired, with abnormalities in the hypothalamus-pituitary-adrenal (HPA) axis with various hormones showing changes in their levels. In women in fertile period, various gonadal hormones are associated with symptoms of the syndrome, but studies focusing only a population of women in post-menopausal period who do not use hormone replacement are rare. We developed an analytical cross sectional study to assess the plasma levels of cortisol and dehidroepiandrosterona sulfate (DHEA-S) with quimioluminescence method in a group of 17 women with FM and 19 healthy women in post-menopause who do not use hormone replacement and observe the correlation with the symptoms of pain through algometry, depression and physical functional capacity measured from the Beck Depression Index (BDI) and the Fibromyalgia Impact Questionnaire (FIQ). Three blood samples were collected in the morning (between 8:00 9:30) with an interval of 24 hours for the measurements of hormonal levels and biochemical profile. There were no immunological or lipid changes in patients with FM. Comparing the two groups, there is no difference in levels of cortisol and a tangential effect for DHEA-S (p=0,094) with the lowest levels in the FM. DHEA-S also correlated with pain threshold (r=0,7) and tolerance (r=0,65) in group FM. We found the presence of depressive state and low physical functional capacity in FM. It was also evident that women in post-menopausal period, DHEA-S should influence the symptoms of increased sensitivity to pain, but not the presence of depressive status and low physical functional

Participação e ação política dos psicólogos frente à política de saúde mental no Piauí

It is intended to problematize forms of participation and political action of psychologists toward mental health policy in Piauí. The study was motivated through challenges faced by the local Psychiatric Reform movement, and the one underway in the country, which needs support technical-assistence and sociopolitical to guarantee accomplishments and to move on with the complete reversion of the asylum to psychosocial model. The method was based on institutional analysis and counted with three insertion moments for the field research: a) to identify historical and political events that configure the local Psychiatric Reform (documental research/oral memory) and to identify psychologists that act in Mental Health; b) to realize participant observation and semi-structured interview with 33 psychologists which act in Mental Health in Teresina; c) to follow the sociopolitical contexts/events of the local Psychiatric Reform (participant observation and conversation circles). The data were analyzed considering four discussion axes, achieved through categorization of the collected material: 1) ways of professional insertion of psychologists in mental health; 2) knowledge and practices used to act in this work context of the profession; 3) political professional movements of workers of the reformist local process; 4) political action of psychologists toward the course of Piauí mental health policy. We concluded identifying that the participation of psychologists in Piauí mental health finds strength by the conduction of its macro and micropolitical professional action. The first one follows oriented by the lemma of social commitment, despite this movement doesn t have equivalence in the transformation of practices and political-professional postures of psychologists in the daily of services. The second is constituted in the every day of work, standing to the political action of the profession implicated with the preservation of the classic modus operandi of being psychologist. Therefore, it is about the actions that give little sustainability technicalassistance to the Psychiatric Reform underway in the State, and why not say in the country

Motivação para o trabalho: um estudo com os profissionais de saúde das unidades básicas de saúde do município de Natal RN

This thesis studied the motivation to work among health professionals of the Basic Unities (BUH) in the health network of the city of Natal (RN). It was understood that the work motivation is a process. Then, the expectation theory was applied and motivation components (results of work, expectative, valence, instrumentality, and motivational force) were used to analyses. It s understanding the motivation as multifaceted phenomenon, the psycho sociological perspective was adopted. The research was developed in two phases: one with application of Work Motivation and Meaning Inventory (WMMI), and another with interview. In the first phases, the analysis of results revealed that the major factors contributing to increase the motivational force to health professionals in the BUH´s are: in valence, Self Expression and Personal Realization (VF2), Personal and Family Survival (VF3); in expectative, Self Expression and Work Justice (EF1), Safety and Dignity (EF2) and Responsibility (EF4); in instrumentality, Involvement (IF1) and Recognition and Economic Independence (IF4). In opposition, the factors that more contribute to reduce the motivational force are Wear and Dehumanization factors in valence (VF4), in expectative (EF3), and in instrumentality (IF4), behind the Work Justice Factor (IF2). Basing in content analysis of interviews, it was possible to associate by equivalence, the senses presented by health professionals with obtained results of first phase, indicating that the results of second phase corroborated and complemented those of first one. This possibility broadened the comprehension of the studied phenomenon. In speaking of the respondents, it was visible the presence of contents showing that they perceive the Health System and BUH´s in degradation. In the first phase, the participants´ instruction also predict the results in motivation, and in the interviews can be saw that the instruction is associated with the opportunities in outside of system. As work motivation is a process, the impact of personal and occupational characteristics tend to interact with contextual aspects. It was concluded the majority of health professionals present the moderated motivational force, but it was falling because they experience and perceive a degrading context with work condition increasingly unfavorable.

Medida da preditividade de instrumentos psicológicos nas avaliações psicológicas de condutores

The object of this study was to identify the possibility of predicting the involvement in traffic infractions from the results of the psychological tests carried out by psychologists specialized in the process of driver licensing in the state of Rio Grande do Norte (RN). The proposal consisted in identifying the penalty points recorded in national driving licenses (CNH) and identifying the corresponding tests and scores obtained, verifying if the average scores in the tests of drivers with and without an infraction record were significantly different and if there is any relation between the test scores and the frequency of the infractions. The results of the psychological instruments were collected in two moments the first being in the act of acquisition of the CNH and the second being during license renewal at the only certified clinic and at the DETRAN-RN. A population of 839 drivers of 14 municipalities were identified. 127 protocols of psychological tests were identified in the records of the DETRAN-RN (2002) and 76 at the clinic (2007), pointing out failures in the process of safekeeping of the psychological material, as well as in its retrieval from the record files. The sample was thus reduced to 68 drivers, all male, with age range between 18 and 41 years old, mean of 21,72 years old (DP = 5,24). 54 drivers were identified without a record of infraction, and 14 with a record. The latter committed 29 infractions. The penalty points recorded in their CNH ranged from 0 to 35 and the typical value of points (median) was zero. In the group with a record of infractions the number of points ranged between 3 and 35, mean of 10,79 (DP = 7,73). Differences were observed in the composition of the battery of tests in the two moments with the same subjects. The use of different tests to assess the same construct of the subject, first and second moment of assessment, did not allow for some analyzes with more efficient statistical proof. It was pointed out that five tests were not carried out and 118 were not corrected/analyzed. Significant differences between the groups were not identified with the psychological instruments used. In another attempt to establish differences between the means, the application of the independent t-Test evidenced a significant difference in the scores of the instruments of concentrated attention in 2002 (t = 2,21, gl = 25, p = 0.037) and of diffuse attention in 2002 (t = 2,37, gl = 24, p = 0.026). The results also did not evidence significant correlation between the scores of the tests and the penalty points of the infractions. Based on this study, it cannot be concluded with precision that the high or low scores are good criteria to determine that a driver will commit more or less traffic infractions, nor that the drivers with higher scores in the tests commit less infractions and vice-versa. Furthermore, the problems to find the instruments and the most basic data require a stronger monitoring on the part of the certified clinic and of the DETRAN-RN.

Adaptação e validação da escala de dependência de exercício físico em versão tradicional e informatizada

While providing physical and psychological benefits, excessive exercise could be or cause a compulsive behavior, making the individual dependent on it. In a parallel discussion, computerized psychological instruments, for a hand, reflects the development of information technology and your applicability to other areas, but also shows little advance for Psychological Assessment. In this perspective, this study aims to adapt the Exercise Dependence Scale (EDS-R) in two formats (paper-and-pencil and computerized) and evaluate evidence of factorial and convergent validity, and reliability of each version and compare them with each other. It is also proposed to observe the relationship of some bio-demographic (Sex, age, frequency, duration and intensity of practice exercise) and the exercise dependence (DEF). For this purpose, 709 regular physical activity practitioners, selected by procedures non-probabilistic sampling, responded a adapted version of EDS-R, Muscle Appearance Satisfaction Scale (MASS), Body Modification Scale (BMS) and a demographic questionnaire, analyzed through Exploratory Factor Analysis, Cronbach's Alpha and not parametric tests. Both the traditional version and the computer showed a seven factors structure, explaining 57 and 62% of the variance, respectively, and Cronbach's alphas of 0.83 and 0.89. Factors were: (1) intentionality, (2) continuity, (3) tolerance, (4) reduction of other activities, (5) lack of control, (6) abstinence and (7) time spent on exercise. Relationships were observed between the Exercise Dependence and the variables: age, diets, consumption of food supplements and medicines for weight change, desire to do plastic surgery and body satisfaction. We observed also a positive correlation between the DEF and the frequency, duration and intensity of exercise, and the factor "Dependence on exercising" from MASS, indicating convergent validity of the EDS-R. Finally, comparisons between the two formats were equivalent, with few changes: computerized version achieved higher DEF scores. Based on these results, it can be concluded that the EDS-R has factorial and convergent validity, reliability, to measure exerceise dependence on traditional e computerized formats. DEF is related to actions used to body modification and behaviors toward exercise. Finally, it was found equivalence between the formats, especially in psychometric parameters, thus suggesting feasibility of a computerized assessment. However, it was observed that the computerized data has sample recruiting strategies more limited

Adaptação transcultural para o Português/Brasil do instrumento vulnerability to abuse screening scale (VASS)

Esse trabalho objetivou promover a adaptação transcultural para o Brasil da VASS. Os passos para adaptação transcultural seguirão a proposta de operacionalização alicerçado na apreciação de diferentes tipos de equivalência: a conceitual e de itens, a semântica e a de mensuração. Para alcançar as duas primeiras etapas utilizou-se as técnicas de tradução e retrotradução associada ao procedimento intitulado Painel de Especialistas. Para o pré-teste e verificação de equivalência de mensuração, aplicou-se o questionário com uma população de 30 e 66 idosos, respectivamente. Para as análises dos resultados foi utilizada a estatística descritiva e inferencial, em especial o KR-20, teste T de student, correlação de Pearson e ANOVA univariada, bem como o método kappa de Fleiss para verificação do índice de confiabilidade. Verificou-se que o conceito utilizado para construção do instrumento, bem como seus itens se mostram adequados à investigação do fenômeno. Evidenciou-se boa equivalência semântica entre os itens das retrotraduções e do instrumento original, especialmente quanto aos resultados de T1 R1. Os juízes optaram pelo uso de 11 itens de T1 à versão-síntese. A equivalência operacional mostrou-se satisfatória. Em geral, os resultados apresentados mostraram-se aceitáveis. Quanto à etapa da equivalência de mensuração, verificou-se que a idade dos participantes variou entre 60 a 84 anos, prevalecendo respondentes idosas (n = 38), representando 57,6% da amostra estudada. O valor do KR-20 para o escore geral do instrumento foi de 0,688 (IC95%: 0,670). Os valores encontrados para as quatro dimensões propostas pelos autores do estudo inicial do instrumento foram 0,528, 0,289, 0,552 e 0,303, respectivamente. Apenas os valores de consistência interna das subescalas Vulnerabilidade e Coerção mostraram-se aproximados aos encontrados no estudo original, a saber, 0,550 e 0,390, respectivamente. Verificou-se que com a retirada dos itens nº 04, nº 06 e nº 10, houve aumento do índice de consistência interna da escala total. Já quanto aos valores da consistência interna das subescalas, percebeu-se que apenas com a retirada dos itens nº 09, referente à escala que dimensiona o Desânimo, e nº 12, item da subescala Coerção, é que houve acréscimo nesses valores. Destaca-se que esses são resultados preliminares, uma vez que após a verificação da adequabilidade e de padrões psicométricos iniciais acerca do uso do instrumento para a população idosa, ainda há de se dar continuidade à etapa concernente à verificação de propriedades psicométricas robustas do instrumento, que indiquem, por exemplo, evidências de fidedignidade em situação de teste-reteste, validade de constructo e de critério, se possível e aplicável. A principal limitação do estudo é a falta de um instrumento padrão-ouro para testar a fidedignidade, sensibilidade e especificidade do instrumento em questão. Apesar desta limitação, a adaptação transcultural e a verificação de propriedades psicométricas preliminares do instrumento de uma medida de autorrelato que afere indicativo de violência doméstica contra o idoso tem sua relevância e foi satisfatória

Ferramentas quimiométricas aplicadas a classificação de amostras de leite em pó e quantificação de proteínas

In this work we used chemometric tools to classify and quantify the protein content in samples of milk powder. We applied the NIR diffuse reflectance spectroscopy combined with multivariate techniques. First, we carried out an exploratory method of samples by principal component analysis (PCA), then the classification of independent modeling of class analogy (SIMCA). Thus it became possible to classify the samples that were grouped by similarities in their composition. Finally, the techniques of partial least squares regression (PLS) and principal components regression (PCR) allowed the quantification of protein content in samples of milk powder, compared with the Kjeldahl reference method. A total of 53 samples of milk powder sold in the metropolitan areas of Natal, Salvador and Rio de Janeiro were acquired for analysis, in which after pre-treatment data, there were four models, which were employed for classification and quantification of samples. The methods employed after being assessed and validated showed good performance, good accuracy and reliability of the results, showing that the NIR technique can be a non invasive technique, since it produces no waste and saves time in analyzing the samples

Construção de modelos multivariados para determinação de lipídios totais e unidade em leite em pó comercial utilizando espectroscopia no infravermelho próximo

In this work calibration models were constructed to determine the content of total lipids and moisture in powdered milk samples. For this, used the near-infrared spectroscopy by diffuse reflectance, combined with multivariate calibration. Initially, the spectral data were submitted to correction of multiplicative light scattering (MSC) and Savitzsky-Golay smoothing. Then, the samples were divided into subgroups by application of hierarchical clustering analysis of the classes (HCA) and Ward Linkage criterion. Thus, it became possible to build regression models by partial least squares (PLS) that allowed the calibration and prediction of the content total lipid and moisture, based on the values obtained by the reference methods of Soxhlet and 105 ° C, respectively . Therefore, conclude that the NIR had a good performance for the quantification of samples of powdered milk, mainly by minimizing the analysis time, not destruction of the samples and not waste. Prediction models for determination of total lipids correlated (R) of 0.9955, RMSEP of 0.8952, therefore the average error between the Soxhlet and NIR was ± 0.70%, while the model prediction to content moisture correlated (R) of 0.9184, RMSEP, 0.3778 and error of ± 0.76%

Estudo de titanatos nanoestruturados obtidos por tratamento hidrotérmico de óxido de titânio em meio alcalino

TiTanate NanoTubes (TTNT) were synthesized by hydrothermal alkali treatment of TiO2 anatase followed by repeated washings with distinct degrees of proton exchange. TTNT samples with different sodium contents were characterized, as synthesized and after heattreatment (200-800ºC), by X-ray diffraction, scanning and transmission electron microscopy, electron diffraction, thermal analysis, nitrogen adsorption and spectroscopic techniques like FTIR and UV-Vis diffuse reflectance. It was demonstrated that TTNTs consist of trititanate structure with general formula NaxH2−xTi3O7·nH2O, retaining interlayer water in its multiwalled structure. The removal of sodium reduces the amount of water and contracts the interlayer space leading, combined with other factors, to increased specific surface area and mesopore volume. TTNTs are mesoporous materials with two main contributions: pores smaller than 10 nm due to the inner volume of nanotubes and larger pores within 5-60 nm attributed to the interparticles space. Chemical composition and crystal structure of TTNTs do not depend on the average crystal size of the precursor TiO2-anatase, but this parameter affects significantly the morphology and textural properties of the nanostructured product. Such dependence has been rationalized using a dissolution-recrystallization mechanism, which takes into account the dissolution rate of the starting anatase and its influence on the relative rates of growth and curving of intermediate nanosheets. The thermal stability of TTNT is defined by the sodium content and in a lower extent by the crystallinity of the starting anatase. It has been demonstrated that after losing interlayer water within the range 100-200ºC, TTNT transforms, at least partially, into an intermediate hexatitanate NaxH2−xTi6O13 still retaining the nanotubular morphology. Further thermal transformation of the nanostructured tri- and hexatitanates occurs at higher or lower temperature and follows different routes depending on the sodium content in the structure. At high sodium load (water washed samples) they sinter and grow towards bigger crystals of Na2Ti3O7 and Na2Ti6O13 in the form of rods and ribbons. In contrast, protonated TTNTs evolve to nanotubes of TiO2(B), which easily convert to anatase nanorods above 400ºC. Besides hydroxyls and Lewis acidity typical of titanium oxides, TTNTs show a small contribution of protonic acidity capable of coordinating with pyridine at 150ºC, which is lost after calcination and conversion into anatase. The isoeletric point of TTNTs was measured within the range 2.5-4.0, indicating behavior of a weak acid. Despite displaying semiconductor characteristics exhibiting typical absorption in the UV-Vis spectrum with estimated bandgap energy slightly higher than that of its TiO2 precursor, TTNTs showed very low performance in the photocatalytic degradation of cationic and anionic dyes. It was concluded that the basic reason resides in its layered titanate structure, which in comparison with the TiO2 form would be more prone to the so undesired electron-hole pair recombination, thus inhibiting the photooxidation reactions. After calcination of the protonated TTNT into anatase nanorods, the photocatalytic activity improved but not to the same level as that exhibited by its precursor anatase