Relationship between sensory processing patterns and gross motor function of children and adolescents with Down syndrome and typical development: a cross-sectional study.

BACKGROUND: Children and adolescents with Down syndrome (DS) may experience impairments in sensory and motor skills that can be interrelated. The purposes of this study were (i) to compare the sensory processing patterns and gross motor function between children and adolescents with DS and with typical development (TD) and (ii) to explore associations between these areas in both DS and TD groups. METHOD: This cross-sectional study involved a sample size of 25 participants with DS (mean age 10.24 ± 2.04 years) and 25 participants with TD (mean age 10.04 ± 2.82 years). The sensory processing patterns were assessed using the Sensory Profile Second Version questionnaire, and the gross motor function was measured with the Gross Motor Function Measure (GMFM-88) dimensions (D) standing, and (E) walking, running, and jumping. Differences between groups were tested using the Mann-Whitney test, and the relationship between the variables was examined using Spearman's correlation tests, with a significance level set at 5%. RESULTS: Children with DS showed greater difficulties with sensory processing than TD children in Seeker (P < 0.001), Avoider (P < 0.001), Sensitivity (P < 0.001), Registration (P < 0.001), Auditory (P < 0.001), Touch (P = 0.001), Movements (P = 0.001), Oral (P = 0.028), Conduct (P = 0.005), Socioemotional (P < 0.001), and Attentional (P < 0.001) domains. Additionally, children with DS presented lower gross motor function than TD in GMFM-88, standing (P < 0.001) and walking, running, and jumping (P < 0.001). Correlations were found between greater difficulties with sensory processing in Touch and lower gross motor function in walking, running, and jumping for the DS group. CONCLUSION: Our results suggest there are more difficulties in sensory processing patterns and gross motor function in children with DS than in TD. Also, there is a single association between more difficulties in sensory processing and less well-developed motor function in the DS group. Therefore, a comprehensive assessment of all these aspects should be performed in children and adolescents with DS, along with the provision of relevant interventions addressing specific needs.

Alterations promoted by acid straightening and/or bleaching in hair microstructures.

Human hair is a biopolymer constituted mainly of keratin intermediate filaments, lipids, pigments and water. Cosmetic treatments usually interact with the hair at the molecular level, inducing changes in its components and modifying the physicochemical and mechanical properties of the fibers. Here, the effect of acid straightening on the morphology and ultrastructure of Caucasian hair was investigated by a group of complementary experimental methods: wide-, small- and ultra-small-angle X-ray scattering; high-resolution 3D X-ray microscopy; quasi-elastic neutron scattering and inelastic neutron scattering; thermogravimetry-mass spectrometry; and differential scanning calorimetry (DSC). X-ray diffraction patterns showed that acid straightening associated with a flat iron (∼180°C) changed the cortex of the fiber, shown by denaturation of the intermediate filaments (measured by DSC). The increase in the spacing of the lipid layers and the observation of the dehydration behavior of the fiber provided indications that water may be confined between these layers, while neutron spectroscopy showed alterations in the vibration mode of the CH2 groups of the lipids and an increase of the proton (H+) mobility in the hair structure. The latter may be associated with the extremely low pH of the formulation (pH ≃ 1). Additionally, this investigation showed that bleached hair (one-time bleached) is more damaged by the action of acid straightening than virgin hair, which was shown by a threefold increase in the percentage of total porosity of the tresses. The obtained results demonstrate that the investigation approach proposed here can provide very important thermodynamic and structural information on induced changes of hair structure, and certainly can be applied for the evaluation of the action mode and efficiency of cosmetic treatments.

Anionic and cationic drug sorption on interpolyelectrolyte complexes.

Interpolyelectrolyte complexes of chitosan and poly(sodium 4-styrenesulfonate) [NaPSS] were synthesized and obtained in the form of solid particles, with two different sulfonate to aminium molar ratios: 0.7, resulting in particles with positive zeta potential (IPEC+), and 1.4, yielding particles with negative zeta potential (IPEC-). Both particles were characterized as potential drug sorbents using differently charged drugs: sodium cromoglycate (negatively charged), and tetracycline hydrochloride (positively charged). The adsorption isotherm for cromoglycate and tetracycline on IPEC+ was adequately described by the Langmuir model, while the IPEC- sorption of tetracycline followed the Redlich-Peterson isotherm without the occurrence of cromoglycate sorption. The sorption kinetics consisted of two processes, one fast and the other slow, which were correlated to purely surface-related interactions and processes that resulted in diffusion and/or destruction/rearrangement on the particle surface and subsurface, respectively. Charge build up equilibrium and kinetics were also monitored via zeta potential measurements, and the differences between mass drug uptake and particle charging were used to propose adsorption mechanisms for the systems studied in this work.

Histological and morphometric characteristics of the corneal layer of buffalo hoof capsules / Características histológicas y morfométricas de la capa cornea de las cápsulas del casco de búfalo

SUMMARY: This study aimed to evaluate the microstructure of the buffalo's hoof capsule using hystomorphometry and computerized light microscopy. The length, thickness, gap and number of epidermal papillae and the morphology of the corneal tubules of the hoof were described in this paper. This study used 56 hoof capsules from hooves of 14 adults - age ranging from 24 to 60 months old - female buffaloes of the Jafarabadi breed; weighing around 650 kg. Fifty-six samples, 28 from thoracic limb and 28 from pelvic limbs, were analyzed, resulting in a total of 112 digits. Clinical specimens were collected at the coronary corium, laminar corium of the abaxial wall and pre-bulbar soles. The study concluded that the microstructure of the hoof capsule of buffalo hooves are made of epidermal papillae measuring 1,721.59 mm of length, 62.94 mm of thickness and 49.02 mm of gap between the papillae. This study determines that the coronary corium has more epidermal papillae than the laminar corium of the abaxial wall and pre-bulbar soles. The corneal tubules of the hoof capsules exhibit helical fashion and points to the possibility of applying this feature to the hooves of the biungulate species as well. In this research, we have been able to determine morphological parameters not yet described in scientific literature. These findings can be used in future comparative studies of healthy cattle and buffaloes and speculate evidence about the hooves' vulnerability facing different hoof diseases.

RESUMEN: El objetivo del estudio fue evaluar la microestructura de la cápsula del casco del búfalo mediante histomorfometría y microscopía óptica computarizada. Se describe la longitud, el espesor, el espacio y el número de papilas epidérmicas y la morfología de los túbulos corneales del casco. Utilizamos 56 cápsulas de cascos de 14 hembras adultas entre 24 a 60 meses de edad de la raza Jafarabadi, cuyo peso aproximado era de 650 kg. Analizamos 56 cascos, 28 del miembro torácico y 28 del miembro pélvico, con un total de 112 dedos. Se recogieron especímenes clínicos en el corion coronario, corion laminar de la pared abaxial y suelas pre-bulbares. Concluimos que la microestructura de la cápsula de los cascos de los búfalos está formada por papilas epidérmicas de 1.721,59 mm de longitud, 62,94 mm de espesor y 49,02 mm de espacio entre papilas. Se determinó que el corion coronario tiene más papilas epidérmicas que el corion laminar de la pared axial y las suelas pre-bulbares. Los túbulos córneos de las cápsulas de casco presentan una forma helicoidal y existe la posibilidad de que esta característica también se aplique a las pezuñas de otras especies de animales biungulados. También se determinaron algunos parámetros morfológicos no descritos en la literatura científica. Estos hallazgos pueden ser útiles en estudios comparativos de ganado bovino y bubalino saludable y en consideración de la 'vulnerabilidad' frente a diferentes enfermedades del casco.

Microtomographic Parameters and Nanoindentation of the Hoof of Girolando Cattle.

The aim of this study was to describe the microstructure of the pigmented and depigmented hoof capsule of Girolando cattle by bi- and tridimensional microtomography and nanoindentation, analysing the possible relation between these findings and the susceptibility of such animals to podal diseases. To carry out the microtomography and the nanoindentation, duplicated samples were collected from the dorsal wall, abaxial wall and pre-bulbar sole of the hoof capsule. Material collection was performed in 40 medial digits of thoracic limbs and 40 lateral digits of pelvic limbs. The bidimensional microtomography showed that the dorsal wall of the thoracic and pelvic limbs presented higher density, followed by the abaxial wall, and finally by the sole, with the lowest density. Moreover, the hoof capsule of cows of Girolando breed is a compact, non-porous material, and constituted by extratubular and intratubular keratin. By the tridimensional microtomography, it was possible to measure the angles of the corneal tubules in relation to the periople and the claws in the different regions of the hoof capsule, which were 90° for the dorsal wall, 55° for the abaxial wall and 70° for the sole. The tridimensional microtomography also showed corneal tubules of different diameters: 17, 51, 85, 119 and 153 µm. The nanoindentation test, when performed in different regions of the hoof capsule, did not reveal significant difference of Vickers hardness in the evaluated areas. However, we verified a larger elastic module of these regions on the transversal cut of the corneal tubules compared to the longitudinal cut.

Microstructure and Hardness of Buffalo's Hoofs.

The aim of this study was to describe the microstructure of hoof capsules of the buffalo. In addition, the study emphasized the morphometric aspects of the horn tubules, the Vickers nanohardness of the dorsal and abaxial walls and sole of the digits of the thoracic and pelvic limbs of the buffalo. The abaxial wall in the thoracic and pelvic digits showed larger diameter of the horn tubules when compared to all dorsal wall and sole. In addition, the abaxial wall of the thoracic digits showed larger diameter of the horn tubules when compared with the pelvic digits. According to the three-dimensional microtomography, the dorsal wall was higher in density compared with the abaxial wall. The latter exhibited an intermediate density, while the sole showed the lowest density. The Vickers nanohardness test showed that there was no difference in hardness and resistance between the experienced regions. However, the elastic modulus was greater on the transversal section of the hoof capsule. In conclusion, the results of the current study show that modern technologies such as microtomography and subsequent imaging can be used to investigate details of the basic morphology in different regions of the buffalo's hoof.

Biochemical composition of the hoof capsule of buffaloes and its influence on hoof quality / Composição bioquímica do estojo córneo de bubalinos e sua influência na qualidade do casco

The purpose of this study was to establish the biochemical parameters of the abaxial wall, dorsal wall and sole of the hoof of the medial thoracic, lateral, and medial pelvic digits of buffalos. The hoof samples were subjected to destructive biochemical analyses to identify the dry material (DM), mineral matter (MM), organic matter (OM), crude protein (CP) and ether extract (EE) contents. Sulfur (S), calcium (Ca), potassium (K), phosphorus (P), zinc (Zn) and copper (Cu) levels were determined based on nondestructive biochemical analyses. The parameters of dry material, mineral matter, organic matter, crude protein and ether extract of hoof capsule of the digits of buffalos can be determined by means of both destructive and nondestructive biochemical analysis. In addition, this study revealed that the highest concentrations of DM, CP and minerals such as, K, Zn and Cu are concentrated in the digits that bear the greatest body mass weight, suggesting that there is a positive correlation between the aforementioned parameters and the strength and growth of the hoof capsule in the digits. As for the element S, this study demonstrated that its highest concentration is located in the lateral digits of the pelvic members.(AU)

O presente estudo objetivou estabelecer os parâmetros bioquímicos da muralha abaxial, muralha dorsal e sola do casco dos dígitos torácico medial e pélvico lateral dos bubalinos. Foram realizadas analises bioquímicas destrutivas das amostras dos cascos para se obterem os teores de matéria seca (MS), matéria mineral (MM), matéria orgânica (MO), proteína bruta (PB) e extrato etéreo (EE). As análises bioquímicas não destrutivas foram empregadas para se avaliarem os níveis de enxofre (S), cálcio (Ca), potássio (K), fósforo (P), zinco (Zn) e cobre (Cu). Concluiu-se que os parâmetros matéria seca, matéria mineral, matéria orgânica, proteína bruta e extrato etéreo do estojo córneo dos dígitos de bubalinos podem ser definidos por análises bioquímicas destrutivas e não destrutivas. Os maiores valores dos elementos minerais estão concentrados nos dígitos que suportam o maior peso do animal, sugerindo que existe uma relação positiva entre esses parâmetros. Além disso, este estudo revelou que as maiores concentrações de MS, PB e minerais como, K, Zn e Cu estão nos dígitos que carregam o maior peso de massa corporal, o que indica que há uma correlação positiva entre os parâmetros acima referidos, resistência e crescimento do estojo córneo dos dígitos. Em relação ao elemento de S, este estudo demonstrou que a sua maior concentração situa-se nos dígitos laterais dos membros pélvicos.(AU)

Insertion of the LINE-1 element in the C-MYC gene and immunoreactivity of C-MYC, p53, p21 and p27 proteins in different morphological patterns of the canine TVT / Inserção do elemento LINE - 1 no gene C-MYC e imunorreatividade das proteinas C-MYC, p53, p21 e p27 nos diferentes padrões morfológicos do tumor TVT

The canine transmissible venereal tumor (TVT) affects the external genitalia of dogs by the natural transplant of viable tumor cells. Thus, this research aimed to diagnose and characterize TVT morphological patterns, identify the insertion of the LINE-1 element in C-MYC gene, by means of the polymerase chain reaction (PCR), and evaluate the immunohistochemical expression of C-MYC, p53, p21 and p27 proteins. The relationship between C-MYC and p53 proteins and their interference on the expression of p21 and p27 were also studied. For that, 20 samples of naturally occurring TVT were used, subjected to cytopathological, histopathological and immunohistochemical analysis, and to molecular diagnosis of neoplasia. The increased tissue expression and the correlation among C-MYC, p53, p21 and p27 proteins indicate reduction and/or loss of their functionality in the TVT microenvironment, with consequent apoptotic suppression, maintenance of cell growth and progression of neoplasia.(AU)

O tumor venéreo transmissível canino (TVT) afeta a genitália externa de cães pelo transplante natural de células tumorais viáveis. Assim, esta pesquisa teve como objetivo diagnosticar e caracterizar TVT em padrões morfológicos, identificar a inserção do elemento LINE-1 em gene C-MYC, por meio da reação em cadeia da polimerase (PCR), e avaliar a expressão imuno-histoquímica do C-MYC, p53, p21 e p27. A relação entre C-MYC e as proteínas p53 e a sua interferência na expressão de p21 e p27 foram também estudadas. Para isso, foram utilizadas 20 amostras de ocorrência natural de TVT, submetido a exame citopatológico, histopatológica e imuno-histoquímica e ao diagnóstico molecular de neoplasia. A expressão aumentada do tecido e a correlação entre a C-MYC e as proteínas p53, p21 e p27 indicam redução e/ou perda de funcionalidade na TVT em seu microambiente, com consequente supressão apoptótica, manutenção do crescimento celular e progressão da neoplasia.(AU)

Assessment of quantitative and qualitative changes of proteoglycans and glycosaminoglycans in normal breast tissue during the follicular and luteal phases of the menstrual cycle.

The effect of sex hormones on extracellular matrix compounds, such as proteoglycans (PGs) and glycosaminoglycans (GAGs), in mammary tissue remains poorly understood. The elucidation of extracellular matrix component functions could clarify pathophysiological conditions, such as cyclical mastalgia (breast pain). The authors examined the quantitative and qualitative changes of PGs and GAGs in normal breast tissue during the follicular and luteal phases of the menstrual cycle. Twenty-eight eumenorrheic patients with benign breast nodules were divided into groups: Group A included 15 follicular patients and Group B included 13 luteal phase patients. Breast tissue adjacent to the nodules was biochemically analyzed to evaluate the types and concentrations of PGS and GAGs. The distribution of proteoglycans during the menstrual cycle was analyzed with immunofluorescence. PG concentrations were elevated (p < 0.01) during the luteal phase compared with the follicular phase, whereas the concentrations of GAGs did not differ significantly. Immunofluorescence revealed that decorin was mainly found in the intralobular stroma. PG concentrations were elevated during the luteal phase, likely due to the influence of sex hormones on macromolecular synthesis. The PG decorin was observed in normal breast tissue in the intralobular stroma. Although the concentration of GAGs, including dermatan and heparan sulfate, varied cyclically, the differences were not significant.

Histomorphological evaluation of the digital coronary region at different fetal development stages of Holstein cattle / Avaliação histomorfológica da região coronária digital em diferentes fases de desenvolvimento fetal de bovinos da raça Holandesa

The scientific literature lacks detailed morphological descriptions of the histological development and cell differentiation of fetal bovine hoof. In this study, 40 extremity members of Holstein bovine fetuses were collected and divided into four groups (G1 to G4) based on the estimated age. Fragments were removed from wall and sole, processed and stained with hematoxylin - eosin (HE) for light microscopy observation. In G1, it was found that the epidermis was very thin, including keratinocyte layers and clusters of mesenchymal cells. In group G2 it was observed that the thickness of the epidermis covering the limbs remained variable and laminar corium developed in the germinal layer. In group G3 it was noted that in the germinal epithelium there were papillae in little advanced development and cells of the stratum corneum in the initial process of keratinization. In G4, the epidermis was well developed with layers distributed homogeneously, containing symmetrical and long papillae and intense production of keratin. In this work, the most important cellular events for the formation of the fetal hoof in Holstein cattle were first described in different stages of their formation.

A literatura científica carece de descrições morfológicas detalhadas sobre o desenvolvimento histológico e diferenciação celular do casco fetal bovino. Neste estudo, 40 extremidades de membros de fetos bovinos da raça Holandesa foram coletados e divididos em quatro grupos (G1 a G4) com base na estimativa da idade. Desses membros, foram retirados fragmentos da parede e sola, processados e corados por hematoxilina-eosina (HE) para observação em microscopia óptica. No grupo G1, observou-se que a epiderme era bastante delgada, incluindo camadas de queratinócitos e conjuntos de células mesenquimais. No grupo G2, foi observado que a espessura da epiderme, cobrindo as extremidades dos membros, permaneceu variável, e o cório laminar desenvolveu-se na camada germinativa. No grupo G3, notou-se, no epitélio germinal, papilas em desenvolvimento pouco avançado e células da camada córnea no processo inicial de queratinização. No grupo G4, a epiderme apresentava-se bem desenvolvida, com camadas distribuídas de forma homogênea, contendo papilas simétricas e longas e com intensa produção de queratina. Neste trabalho, os eventos celulares mais importantes para a formação do casco fetal em bovinos da raça Holandesa foram descritos pela primeira vez, em diferentes etapas da sua formação.

Prolonged respiratory viral shedding in transplant patients.

Respiratory viral infections are frequent causes of morbidity in transplant patients. We screened symptomatic adult transplant recipients for respiratory viruses in a cohort of patients attending a referral medical center in Brazil. The duration of viral shedding and the prevalence of viral codetections were also determined. During a 1-year period (2011-2012), swabs were obtained from 50 patients. An in-house polymerase chain reaction panel designed to detect 10 viruses was used. Viruses were identified in 19 (38%) patients, particularly parainfluenza III (32%) and the respiratory syncytial virus (20%); multiple viruses were identified in 26% of patients. Prolonged viral shedding was observed with 60% of individuals excreting viruses for >10 days. The clinical and epidemiologic relevance of prolonged viral shedding remains to be determined.

Equilibrium and kinetic aspects of sodium cromoglycate adsorption on chitosan: mass uptake and surface charging considerations.

Chitosan has more and more been suggested as a material for use as adsorbent in the treatment of effluents as well as in the synthesis of drug-loaded nanoparticles for controlled release. In both cases, a good understanding of the process of adsorption, both kinetically and in terms of equilibrium, has an importance of its own. In this manuscript we study the interaction between sodium cromoglycate, a drug used in asthma treatment, and chitosan. Equilibrium experiments showed that Sips (or Freundlich-Langmuir) isotherm described well the resultant data and adsorption possibly occurred as in multilayers. A model based on ordinary reaction-rate theory, compounded of two processes, each one with a correlated velocity constant, described the kinetics of sorption. Kinetic and equilibrium data suggested the possibility of surface rearrangement, favored by the increase of temperature.

Tetracycline adsorption on chitosan: a mechanistic description based on mass uptake and zeta potential measurements.

Adsorption phenomena occurring at the solid/liquid interface of chitosan particles are of extreme importance in the kinetics of drug release/upload as well as in effluent treatment by adsorption. In this work, equilibrium and kinetic aspects of protonated tetracycline adsorption on chitosan are explored using classic solution depletion method and zeta potential measurements. Equilibrium experiments showed that for solutions with tetracycline initial concentration of ca. 1.2 g L(-1), corresponding to a pH around 3, chitosan structure disrupted, as indicated by an increase in magnitude of tetracycline sorption. Adsorption and zeta potential isotherms before disruption suggested that the process of adsorption had a Langmuir character up to a point at which subsurface was exposed to adsorption; at this point, a second mode of sorption began: zeta potential tended to an equilibrium value, following Sips isotherm and tetracycline sorption had a linear dependence on its continuous phase concentration. The kinetics of tetracycline sorption suggested that sorption of tetracycline was divided between the sorption of protonated and non-protonated tetracycline; tetracycline in its non-protonated form seemed to rule the sorption of tetracycline.

Anti-diabetic activity of extract from Persea americana Mill. leaf via the activation of protein kinase B (PKB/Akt) in streptozotocin-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Persea americana Mill. (Lauraceae) have been popularly used in the treatment of diabetes in countries in Latin America and Africa. AIM OF THE STUDY: To investigate the hypoglycaemic properties and to determine the molecular mechanism by which the hydroalcoholic extract of the leaves of Persea americana reduce blood glucose levels in streptozotocin (STZ)-induced diabetes in rats via the enzymatic pathway of protein kinase B (PKB/Akt). METHODS: The hydroalcoholic extract of the leaves of Persea americana (0.15 and 0.3g/kg/day), vehicle and metformin (0.5g/kg/day) were administered orally to STZ-diabetic rats (n=7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation and the expression of PKB in the liver and soleus muscle were determined by Western blot. RESULTS: The hydroalcoholic extract of the leaves of Persea americana reduced blood glucose levels and improved the metabolic state of the animals. Additionally, PKB activation was observed in the liver and skeletal muscle of treated rats when compared with untreated rats. CONCLUSION: The results indicate that the hydroalcoholic extract of the leaves of Persea americana has anti-diabetic properties and possibly acts to regulate glucose uptake in liver and muscles by way of PKB/Akt activation, restoring the intracellular energy balance.

DMAICR in an ergonomic risks analysis.

The DMAICR problem-solving methodology is used throughout this paper to show you how to implement ergonomics recommendations. The DMAICR method consists of the following five six steps by which you can solve ergonomic design problems: The steps of the proposed method, adapting DMAICR, are the following: In the steep D, there is the definition of the project or the situation to be assessed and its guiding objectives, known as demand. In the step M, it relates to the work, tasks and organizational protocols and also includes the need of measuring. In the step A, all concepts are about the analysis itself. The step I is the moment of improving or incrementing. In the step C, control, prevention from prospective troublesome situation and implementation of management are the activities controlling the situation. R is Report. Some relevant technical and conceptual aspects for the comparison of these methodologies are illustrated in this paper. The steps of DMAICR were taken by a multifunctional team (multi-professional and multi-disciplinary) termed as focus group, composed by selected members of the company and supported by experts in ergonomics.

Separação e identificação de ácidos graxos em formulações cosméticas contendo óleo de castanha do Brasil por eletroforese capilar / Separation and identification of fatty acids in cosmetic formulations containing Brazil nut oil by capillary electrophoresis

An analytical method based on capillary electrophoresis (CE) with a partially aqueous electrolyte system was developed to enable the free fatty acids of Brazil nut oil to be identified in cosmetic formulations. In this study, a gel cream formulation was developed and its oil phase was extracted with a mixture of chloroform-methanol-water (1:2:0.8 v/v/v). The chloroform layer was saponified with a methanolic solution of NaOH (0.5 mol L-1) at 75-80 °C for 25 minutes. Experiments were carried out on a Beckman PACE/MDQ CE system (Fullerton, CA, USA) equipped with an on-column, diode-array detection system set at 254 nm and at 25ºC. The electrolyte consisted of 12.5 mmol L-1 sodium tetraborate buffer pH 7.0, 12.5 mmol L-1 polyoxyethylene 23-lauryl ether, 7.5 mmol L-1 sodium dodecylbenzenesulfonate (used as chromophore for indirect UV detection) and acetonitrile (35% v/v). The proposed method allowed the separation and identification of the fatty acids of Brazil nut oil in a cosmetic gel cream, as well as enabling possible interference by the oily phase components in the formulation to be identified.

Um método de análise por eletroforese capilar com sistema de eletrólito parcialmente aquoso foi desenvolvido para identificar os ácidos graxos livres do óleo de Castanha do Brasil em formulações cosméticas. No presente trabalho foi desenvolvida uma formulação cosmética (gel creme) cuja fase oleosa foi extraída com uma mistura de clorofórmio-metanol-água (1:2:0.8 v/v/v). A camada de clorofórmio, foi saponificada com solução de NaOH em metanol (0,5 mol L-1) a 75-80 °C durante 25 minutos. Os experimentos foram realizados em sistema de eletroforese capilar Beckman PACE/MDQ (Fullerton, CA, USA), com detecção de arranjo de diodos a 254 nm e a 25 ºC. O eletrólito utilizado foi 12,5 mmol L-1 de tetraborato de sódio tampão a pH 7,0, 12,5 mmol L-1 de éter de polioxietileno 23-lauril, 7,5 mmol L-1 de dodecilbenzenosulfonato de sódio (utilizado como agente cromóforo para detecção UV indireta) e acetonitrila (35% v/v). O método proposto permitiu a separação e a identificação dos ácidos graxos do óleo de Castanha do Brasil em formulações cosméticas, bem como possibilitou a identificação de interferências presentes na fase oleosa da formulação.

The kinetics of adsorption of tetracycline on chitosan particles.

Experiments to monitor and characterize the kinetics of adsorption of tetracycline on chitosan particles are reported in this work. The same pseudo-order kinetics that has been widely used for describing the adsorption in systems related to wastewater purification and drug loading was used to treat the present data. As some unexpected results came out from the experiments, it was necessary a detailed deduction for this sort of kinetics to be carried out, so that approximations related to short and long times were obtained. Firstly it was shown that an apparently linear t/q(t) versus t relationship did not imply a pseudo-second-order sorption kinetics, differently of what has been repeatedly reported in the literature. It was found that this misinterpretation could be avoided by using non-linear regression. Finally, the adsorption of tetracycline on chitosan particles was analyzed, using the insights obtained from theoretical analysis, and the parameters generated were used to analyze to adsorption kinetics and to propose an adsorption mechanism.

Determination of tocopheryl acetate and ascorbyl tetraisopalmitate in cosmetic formulations by HPLC.

A rapid HPLC method was developed for the assay of tocopheryl acetate and ascorbyl tetraisopalmitate in cosmetic formulations. The validated method was applied for quantitative determination of these vitamins in simulated emulsion formulation. Samples were analysed directly on a RP-18 reverse phase column with UV detection at 222 nm. A mixture of methanol and isopropanol (25 : 75 v/v) was used as mobile phase. The retention time of tocopheryl acetate and ascorbyl tetraisopalmitate were 3.0 min and 5.9 min, respectively. Recovery was between 95% and 104%. In addition, the excipients did not interfere in the analysis. The method is simple, reproducible, selective and is suitable for routine analyses of commercial products.

Acute and subacute toxicity of the Carapa guianensis Aublet (Meliaceae) seed oil.

Carapa guianensis (Meliaceae), known as Andiroba in Brazil, has been used by Amazon Rainforest indigenous communities for treatment of coughs, convulsions, skin diseases, arthritis, rheumatism, ear infections, to heal wounds and bruises and as an insect repellent. Carapa guianensis seed oil (SO) was evaluated for its acute and subacute toxicity (30 days) by the oral route in Wistar rats. In the acute toxicity test, SO (0.625-5.0g/kg, n=5/sex) did not produce any hazardous symptoms or deaths. The subacute treatment with SO (0.375, 0.75 and 1.5g/kg, n=10/group) failed to change body weight gain, food and water consumption. Hematological analysis showed no significant differences in any of the parameters examined. However, in the biochemical parameters, there was an increase in the alanine aminotransferase (ALT) serum level (29%) in the group SO 1.5g/kg. In addition, absolute and relative liver weights were increased at the doses of 0.75g/kg (23.4 and 19.1%) and 1.5g/kg (18.7 and 33.1%). In conclusion, acute and subacute administration of Carapa guianensis seed oil did not produce toxic effects in male Wistar rats. However, the increase in the ALT serum level and in both absolute and relative liver weights may indicate a possible hepatic toxicity.