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This study seeks to investigate the local reinforcement of low carbon cast steel specimens with WC–metal matrix composites (WC–MMCs), to obtain a new material effective in competing with hard alloy steels. For this purpose, a powder compact of tungsten carbide (WC) and iron (Fe) was prepared and placed in the mold cavity before casting. The reactions that occurred with the molten steel led to the formation of the WC–MMC and, consequently, to the local reinforcement of the steel. The microstructure of the WC–MMC reinforcement was characterized by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and electron backscatter diffraction (EBSD). The results showed a microstructural variation throughout the depth of the reinforcement. In the surface region, most of the original WC particles retain their polygonal morphology, but towards the base metal, the dissolution of the WC particles increased with the formation of (Fe,W)6C carbides. Closer to the base metal, dendritic eutectic carbides of (Fe,W)6C and fine (Fe,W)23C6 precipitates in a matrix of martensite were formed. The mechanical properties of the reinforcement were evaluated by hardness and ball-cratering abrasion tests. The results revealed a significant increase in hardness, being three times harder than the base metal, and a decrease of 39% in the wear rate.

In this work, austenitic stainless steel specimens were locally reinforced with WC particles. The reinforcements were fabricated via an ex situ technique based on powder technology. Mixtures of WC, Fe, and M0101 binder were cold-pressed to obtain powder compacts. After debinding and sintering, the porous WC–Fe inserts were fixed in a mold cavity, where they reacted with liquid metal. Microstructural analysis was conducted for characterization of the phases constituting the produced reinforcement zone and the bonding interface. The results revealed that the reinforcement is a graded material with compositional and microstructural gradients throughout its thickness. The zone nearest to the surface has a ferrous matrix with homogeneously distributed WC particles and (Fe,W,Cr)6C and (Fe,W,Cr)3C carbides, formed from the liquid metal reaction with the insert. This precipitation leads to austenite destabilization, which transforms into martensite during cooling. A vast dissolution of the WC particles occurred in the inner zones, resulting in more intense carbides formation. Cr-rich carbides ((Fe,Cr,W)7C3, and (Fe,Cr,W)23C6) formed in the interdendritic regions of austenite; this zone is characterized by coarse dendrites of austenite and a multi-phase interdendritic network composed of carbides. An interface free of discontinuities and porosities indicates good bonding of the reinforcement zone to stainless steel., This research was funded by FEDER through the program P2020|COMPETE, Projetos em Copromoção (project POCI-01-0247-FEDER-033417), and the program P2020|Norte2020, Programas doutorais (NORTE-08-5369-FSE-000051).

Super duplex stainless steels are prone to the formation of undesirable secondary phases, particularly when exposed to slow cooling rates. In the current study, the mechanisms of formation of secondary phases have been characterized using a combination of optical microscopy, scanning electron microscopy, and transmission electron microscopy, on samples aged at temperatures ranging between 700 °C and 1000 °C. Among the possible secondary phases, χ-phase and σ-phase were detected and identified as the main phases responsible for the destabilization of the duplex microstructure. The kinetics of both phases were assessed. In particular, the χ-phase forms prior to σ-phase, until it starts to convert into σ-phase. Finally, the TTT curves for the stable σ-phase were calculated. We found that the precipitation of the σ-phase starts as early as 30 seconds at 950 °C.

This literature review aims to summarize the research conducted on the production of locally reinforced ferrous castings based on metal matrix composites reinforced with TiC (TiC-MMCs). One way to improve the wear resistance of cast components is to reinforce critical regions locally with metal matrix composites (MMCs) without changing the toughness of the component core. The in situ method of self-propagating high-temperature synthesis is one of the main approaches for the production of this enhanced material. Using this approach, the reinforcement is formed from a powder compact inserted in the mold cavity. The temperature of the liquid metal then produces the combustion reactions of the powders, which promote the formation of the ceramic phase. This paper focuses on eight powder systems used to synthesize TiC: Ti-C, Ni-Ti-C, Ni-Ti-B4C, Fe-Ti-C/Fe-Cr-Ti-C, Cu-Ti-B4C, Al-Ti-C, and Al-Ti-B4C, and provides an overview of the methodologies used as well as the effect of processing variables on the microstructural and mechanical characteristics of the reinforcement zones.

Chemical, physical, thermal, and mechanical behavior of complex alloys, such as super-duplex stainless steels (SDSS), is largely dependent on the characteristics of its multiphase microstructure which is controlled by chemical composition and cooling rate in the temperature range of 1000 to 300 ℃. During solidification, a microstructure composed of ferrite, austenite, and non-ideal phases can be formed, introducing residual stresses due to the different coefficient of thermal expansion and elastoplastic properties of the phases. Since residual stresses may have a significant impact on components, causing distortion and early failure, it is critical to understand their origin (at the microscale) and effect (at the macroscale). Multiscale material modeling provides an opportunity to analyze the material in different scales, leading to the optimization of material design and behavior. This work addresses the effect of distribution and volume fraction of phases on the magnitude and gradient of residual stresses on a cast SDSS specimen. The numerical method for the homogenization of the material properties is also addressed. The procedure followed consisted of modeling the microstructure by assigning phases properties to the features in optical micrographs and generating a finite element mesh to compute the macroscopic material properties. The software OOF was used to model the microstructures and ABAQUSTM/CAE was applied to simulate the cooling of the specimen and to analyze the residual stresses.

High-chromium white cast iron (WCI) specimens locally reinforced with WC&ndash, metal matrix composites were produced via an ex situ technique: powder mixtures of WC and Fe cold-pressed in a pre-form were inserted in the mold cavity before pouring the base metal. The microstructure of the resulting reinforcement is a matrix of martensite (&alpha, &rsquo, ) and austenite (&gamma, ) with WC particles evenly distributed and (Fe,W,Cr)6C carbides that are formed from the reaction between the molten metal and the inserted pre-form. The (Fe,W,Cr)6C precipitation leads to the hypoeutectic solidification of the matrix and the final microstructure consists of martensite, formed from primary austenite during cooling and eutectic constituent with (Fe,Cr)7C3 and (Fe,W,Cr)6C carbides. The presence of a reaction zone with 200 &micro, m of thickness, between the base metal and the composite should guarantee a strong bonding between these two zones.

In sand casting of metallic alloys, the cooling rate is a key parameter that affects the microstructure and the appearance of defects and residual stresses in the end cast components. In this work, a numerical model was developed to simulate the cooling of a duplex stainless steel casting on a furan-bonded sand mold. The heat transfer coefficient (HTC) as a function of temperature was determined by an inverse method. A good agreement between experimental and numerical cooling curves was achieved, showing the importance of estimating HTC as a function of temperature. On the basis of these results, it is possible to calculate thermal residual stresses and model the microstructure of duplex stainless steel castings with complex geometries.

An overview of several candidate architectures for 100 Gb/s capable optical access networks is presented. Considerations for their system requirements are outlined in regards to performance, cost and energy efficiency, towards addressing the design issues for the next generation EPON.

High-chromium white cast irons are widely used in a variety of applications that require high wear resistance. This outstanding performance is due to the presence of large amounts of chromium carbides which exhibit high hardness. However, for wear-resistant applications exposed to impact, ductile cast iron is a candidate material due to its good wear behaviour, reduced brittleness and lower production costs. That is the case of the working rolls employed in clay mass rolling operations which operate under significant wear conditions and impacts (due to foreign bodies mixed in the ceramic mass). In the present study, the effect of the chemical composition on microstructure and abrasion wear of two high-chromium white cast irons (13% Cr and 19% Cr) and a chilled ductile cast iron with 0.6% Cr was investigated. The microstructural characteristics and hardness were evaluated and correlated with the wear data. Ball cratering tests, using abrasive slurry containing SiC particles, were carried out to rank the abrasive wear resistance of the alloys, in the as-cast condition, obtained by permanent mould casting. The alloy with the highest chromium content (and higher ratio Cr/C = 6.8) presents a larger volume fraction of chromium-richer carbides providing better wear resistance. Ductile iron exhibits good wear performance in the chilled region due to a fine abrasion-resistant carbide network.

The purpose of this study was to test the hypotheses that in obese children: 1) hypocaloric diet (D) improves both heart rate recovery at 1 min (Δ HRR1) cfter an exercise test, and cardiac autonomic nervous system activity (CANSA) in obese children; 2) Diet and exercise training (DET) combined leads to greater improvement in both Δ HRR1 after an exercise test and in CANSA, than D alone. Moreover, we examined the relationships among Δ HRR1, CANSA, cardiorespiratory fitness and anthropometric variables (AV) in obese children submitted to D and to DET. 33 obese children (10 ± 0.2 years; body mass index (BMI) >95 (th) percentile) were divided into 2 groups: D (n=15; BMI=31 ± 1 kg/m²)) and DET (n=18; 29 ± 1 kg/m²). All children performed a maximal cardiopulmonary exercise test on a treadmill. The Δ HRR1 or LF/HF ratio (P>0.05). In contrast, the DET group showed increased peak VO₂ ( P=0.01) and improved Δ HRR1 (Δ HRR1=37.3 ± 2.6; P=0.01) and LF/HF ratio ( P=0.001). The DET group demonstrated significant relationships among Δ HRR1, peak VO₂ and CANSA (P

This study examined forearm vasodilatation during mental challenge and exercise in 72 obese children (OC; age = 10 ± 0.1 years) homozygous with polymorphism in the allele 27 of the β2-adrenoceptors: Gln27 (n = 61) and Glu27 (n = 11). Forearm blood flow was recorded during 3 min of each using the Stroop color-word test (MS) and handgrip isometric exercise. Baseline hemodynamic and vascular measurements were similar. During the MS, peak forearm vascular conductance was significantly greater in group Glu27 (Δ = 0.35 ± 0.4 vs. 0.12 ± 0.1 units, respectively, p = .042). Similar results were found during exercise (Δ = 0.64 ± 0.1 vs. 0.13 ± 0.1 units, respectively, p = .035). Glu27 OC increased muscle vasodilatory responsiveness upon the MS and exercise.

Summary Background Leprosy is characterized by a disease spectrum having two polar clinical forms dependent on the presence or not of cell-mediated immunity. In the tuberculoid forms, granuloma-activated macrophages kill Mycobacterium leprae in conjunction with a Th1 response while, in multibacillary (MB) lesions, M. leprae nonactivated macrophages infiltrate the nerves and internal organs together with a Th2 response. The functional properties and activation pathways of macrophages isolated from patients with MB leprosy remain only partially understood. Objectives To establish an ex vivo methodology capable of evaluating the activation pathways, grade and fate of cultured macrophages isolated from MB lesions. Methods Skin biopsies from patients with borderline tuberculoid, bordeline lepromatous and lepromatous leprosy (LL) were characterized by immunohistochemistry and transcriptional analysis. To isolate inflammatory cells, a portion of the samples was submitted to enzymatic digestion. These same cells, maintained in culture for a minimum 7-day period, were characterized morphologically and via flow cytometry at different culture time points. Cytokine [interferon (IFN)-γ, tumour necrosis factor (TNF)-α and interleukin (IL)-10] mRNA levels were quantified by real-time polymerase chain reaction and protein secretion in the culture supernatants was measured by enzyme-linked immunosorbent assay and the nitric oxide levels by Griess reagent. Results RNA expression in tuberculoid and MB lesions showed the profile expected of characteristic Th1 and Th2 responses, respectively. The inflammatory cells in all biopsies were successfully isolated. Although the number of cells varied between biopsies, it was highest in LL biopsies. The frequency of isolated CD14+ and CD3+ cells measured by flow cytometry correlated with the percentages of macrophages and lymphocytes in the lesions. Throughout the culture period, CD68+ macrophages showed morphological changes. A progressive increase in cell number and reduction of infected cells were perceptible in the cultures. In contrast to the biopsies, TNF-α, IFN-γ and IL-10 expression in the tuberculoid and MB leprosy cells in 24-h culture and the cytokine levels in the supernatants did not differ significantly. During the culture period, cytokine expression in the MB cells progressively declined, whereas, from days 1 to 7, nitrite levels progressively increased. After day 40, the remaining macrophages were able to ingest fluorescein isothiocyanate-labelled M. leprae. These data need to be confirmed. Conclusions This study confirmed the feasibility of obtaining ex vivo macrophages from leprosy lesions and keeping them in long-term culture. This procedure may open new pathways to studying the interaction between M. leprae and human macrophages, which might, in turn, lead to the development of therapeutic tools capable of overcoming the specific anergy found in patients with MB leprosy.

Three-hundred-and-ninety-seven children aged 2-59 mo presenting to the paediatric emergency departments of five public hospitals in Sao Paulo Brazil with an acute episode of lower respiratory disease were examined. The children were classified into the following diagnostic categories: acute bronchitis acute bronchiolitis pneumonia asthma post-bronchiolitis wheezing and wheezing of uncertain aetiology. Three years after the initial study the homes of the children diagnosed as asthmatic or as having wheezing of uncertain aetiology were visited to collect information on subsequent episodes of lower respiratory disease. This paper reports the proportional incidence of different categories of lower respiratory disease and the results of an analysis to investigate clinical features that might distinguish wheezing children between those with asthma and those with an infectious disease. The predictions made for children with wheezing of uncertain aetiology were then compared with the follow-up data. Recurrent wheezing disorders (asthma post-bronchiolitis wheezing) were common in the study sample (47% of children). Thirty-six percent of children with an initial diagnosis of wheezing of uncertain aetiology were diagnosed as asthmatic by another doctor over the next 3 y. We were unable to identify any clinical features that were useful in identifying those children likely to be diagnosed subsequently as asthmatic. The use of a diagnostic category similar to that which we have called "wheezing of uncertain aetiology" might help to alert physicians early to the possibility of asthma without interfering in the management of the illness. Such a classification might also be useful in epidemiological investigations of the aetiology of lower respiratory diseases. (authors)

The intake of mycotoxin-contaminated feeds can lead to nutrient losses and may have adverse effects on animal health and on productivity. The aims of this study were (1) to determine the mycobiota present in poultry feed samples, and (2) to evaluate the natural occurrence of aflatoxin B(1), fumonisin B(1) and zearalenone. Fungal counts were similar between all culture media tested (10(3 )CFU g(-1)). The most frequent genus isolated was Penicillium spp. (41.26%) followed by Aspergillus spp. (33.33%) and Fusarium spp. (20.63%). High precision liquid chromatography was applied to quantify aflatoxin B(1) and fumonisin B(1). Thin layer chromatography was used to determine zearalenone levels. Aflatoxin B(1 )values ranged between 1.2 and 17.5 microg kg(-1). Fumonisin B(1) levels ranged between 1.5 and 5.5 microg g(-1). Zearalenone levels ranged between 0.1 and 7 microg g(-1). The present study shows the simultaneous occurrence of two carcinogenic mycotoxins, aflatoxin B(1) and fumonisin B(1), together with another Fusarium mycotoxin (zearalenone) in feed intended for poultry consumption. Many samples contained AFB(1 )levels near the permissible maximum and it could affect young animals. A synergistic toxic response is possible in animals under simultaneous exposure.

Dieta hipocalórica e atividade física aeróbia promovem perda de peso e melhora do perfil lipídico de adultos obesos, entretanto pouco se conhece em crianças obesas, sendo este o objetivo do trabalho. Estudamos cinqüenta crianças obesas e dividimos em dois grupos pareados: Grupo D (dieta com 55% de carboidrato, 30% de gordura e 15% de proteína - 1.500 e 1.800 kcal) e Grupo DE (mesma dieta + atividade física aeróbia 1 hora por dia, três vezes por semana). Após cinco meses, avaliamos: índice de massa corpórea (IMC), triglicerídeos, colesterol total (CT) e frações. Nenhuma modificação foi observada nos triglicerídeos, CT e lipoproteína de baixa-densidade colesterol (LDL-C) em ambos os grupos. Houve, porém, aumento da lipoproteína de alta-densidade colesterol (HDL-C) apenas no grupo DE (+10,3%, p< 0,01). Selecionando pacientes com CT > 170 mg/dL, LDL-C > 110 mg/dL e HDL-C < 35 mg/dL, observou-se redução semelhante do CT nos dois grupos (-6,0% x -6,0%; p= ns), assim como da LDL-C de ambos (-14,2% x -13,5%; p= ns), e um acréscimo da HDL-C apenas no grupo DE (+10,0%; p< 0,05). Conclusões: 1) Dieta hipocalórica (DH) e atividade física aeróbia promovem aumento da HDL-C, independente do valor basal, em crianças obesas quando comparado à DH isoladamente; 2) DH isoladamente ou associada a exercício aeróbio reduz CT e LDL-C, quando estes estão em níveis acima do valor normal, em crianças obesas. Diet and exercise help improve obese adults' lipid profile. However, their effect on obese children, the aim of the present study, is poorly known. Fifty obese children were studied into 2 paired groups: Group D (1,500 - 1,800 kcal diet: 55% carbohydrate, 30% fat, 15% protein), and Group DE (same diet + aerobic physical activity 1 hour/day 3 times a week). After 5 months BMI, triglycerides, total cholesterol (TC) and fractions were assessed. No change in triglycerides, TC and low-density lipoprotein cholesterol (LDL-C) levels were reported in both groups. However, high-density lipoprotein cholesterol (HDL-C) increased (+10.3%; p< 0.01) only in DE Group. Screening patients with TC > 170 mg/dL, LDL-C > 110 mg/dL and HDL-C < 35 mg/dL we had: similar reduction for TC in both groups (-6.0% x -6.0%; p= ns), LDL-C reduction in both groups (-14.2% x -13.5%; p= ns), and HDL-C increase only in DE Group (+10.0%; p< 0.05). Conclusions: 1) Hypocaloric diet (HD) + exercise, rather than diet only, increase obese children's HDL-C levels irrespective of baseline levels; 2) HD only and HD + exercise lead to TC and LDL-C reduction in obese children with TC and LDL-C above normal values.

Aims: The objective of this study was to determine the ochratoxin (OT) and aflatoxin (AF) production by three strains of Aspergillus spp. under different water activities, temperature and incubation time on barley rootlets (BR). Methods and Results: Aspergillus ochraceus and Aspergillus flavus were able to produce mycotoxins on BR. Aspergillus ochraceus produced ochratoxin A (OTA) at 0AE80 water activity (aw), at 25 and 30� C as optimal environmental conditions. The OTA production varies at different incubation days depending on aw. Aflatoxin B1 (AFB1) accumulation was obtained at 25� C, at 0AE80 and 0AE95 aw, after 14 and 21 incubation days respectively. Temperature was a critical factor influencing OTA and AFB1 production. Conclusions: This study demonstrates that BR support OTA and AFB1 production at relatively low water activity (0AE80 aw) and high temperatures (25‐30� C). Significance and Impact of the Study: The study of ecophysiological parameters and their interactions would determine the prevailing environmental factors, which enhance the mycotoxin production on BR used as animal feed.

PurposeTo provide the basis for the development of a specific benchmarking methodology for the foundry industry.Design/methodology/approachThe methodology was developed with the support of the Portuguese Foundry Association (APF). The project was structured in two stages: developing the model for the performance assessment (including performance indicators specially designed for the foundry companies); and conducting a pilot benchmarking exercise in order to validate the model. Both stages received the contribution of eight relevant national foundries.FindingsProvides information about expectations of the benchmarking partners group. Make available a specific benchmarking model for assessing the foudries' performance based on critical factors. Provides foundry‐oriented indicators. Confirms that benchmarking is a time‐consuming tool, demanding continuous commitment of the top‐managers.Research limitations/implicationsA limitation of the study is the number of benchmarking partners (eight foundries). The statistical analysis of the results based on this small sample was not practicable, preventing the definition of the presumed causal relations between improvement practices and performance outcomes.Practical implicationsThe benchmarking model is now available at the APF. From now on, this institution can provide its members with a tool for promoting the co‐operation among companies and to enhance and enlarge significantly the available information about this sector. This activity will, certainly, help to improve organisations' performance, upgrading the competitiveness of the metalcasting industry in Portugal.Originality/valueThis paper helps the development of benchmarking in the metalcasting industry in which the number of published studies is very limited.

Background— The effects of diet and diet plus exercise training on muscle vasodilatation during physiological maneuvers in obese children are unknown. We tested the hypothesis that (1) blood pressure (BP) and forearm vascular conductance (FVC) responses during handgrip exercise and mental stress would be altered in obese children and (2) diet plus exercise training would restore BP and FVC responses during exercise and mental stress in obese children. Methods and Results— Thirty-nine obese children (aged 10±0.2 years) were randomly divided into 2 groups: diet plus exercise training (n=21; body mass index [BMI]=28±0.5 kg/m 2 ) and diet (n=18; BMI=30±0.4 kg/m 2 ). Ten age-matched lean control children (BMI=17±0.5 kg/m 2 ) were also studied. Forearm blood flow was measured by venous occlusion plethysmography. BP was monitored noninvasively. Handgrip exercise was performed at 30% maximal voluntary contraction for 3 minutes. Stroop color word test was performed for 4 minutes. Baseline BP was significantly higher and FVC was significantly lower in obese children. During exercise and mental stress, BP responses were significantly higher and FVC responses were significantly lower in obese children. Diet and diet plus exercise training significantly reduced body weight. Diet and diet plus exercise training significantly decreased BP levels during exercise and mental stress. Diet plus exercise training, in contrast to diet alone, significantly increased FVC responses during exercise (3.7±0.3 versus 5.6±0.4 U; P =0.01) and mental stress (3.5±0.5 versus 4.5±0.4 U; P =0.02). After diet plus exercise training, BP and FVC responses during exercise and mental stress were similar between obese children and the control group. Conclusions— Obesity exacerbates BP responses and impairs FVC responses during exercise and mental stress in children. Diet and exercise training restore BP and FVC responses in obese children.

A aflatoxina M1 (AFM1) tem sido detectada em leite de animais alimentados com ração contaminada por aflatoxina B1 (AFB1), possuindo efeitos tóxicos e carcinogênicos muito próximos. Constitui-se um problema de Saúde Pública, pois sua toxidez é preocupante, quando os indivíduos mais jovens estão entre os maiores consumidores de leite e estes são os mais sensíveis a seus efeitos. O objetivo deste trabalho foi determinar a presença de aflatoxinas em alimentos destinados a bovinos e de AFM1 em amostras de leite cru e após pasteurização. Trabalhou-se inicialmente com 12 produtores de leite, permanecendo apenas 2 produtores que apresentavam valores significativos de aflatoxina M1. A coleta de leite foi realizada 24 h após a coleta do alimento. O método utilizado para a detecção de aflatoxinas no alimento foi a cromatografia em camada delgada. A determinação de AFM1 em leite foi realizada empregando-se coluna de imunoafinidade para a purificação e detecção por cromatografia líquida de alta eficiência em fase reversa. Não foram detectadas aflatoxinas nas amostras de ração. Entretanto, detectou-se AFM1 em 19 (52,8%) das 36 amostras de leite cru, em valores que variaram de traços a 74,1 ng L-1. Em leite pasteurizado, a AFM1 foi detectada em 13 (38,2%) das 34 amostras, em níveis que variaram desde traços a 58,9 ng L-1. Os valores encontrados de aflatoxina no leite estão dentro dos padrões tolerados pela legislação brasileira. As concentrações de aflatoxina nos leites cru e pasteurizado não diferiram entre si (p>0,05). O fato de não se ter detectado aflatoxinas na ração pode ser explicado pela sua ocorrência em baixas concentrações, isto é, inferiores ao limite de detecção do método utilizado (2 mg/Kg), o que não impediria o aparecimento da AFM1 no leite e a detecção mediante metodologia mais sensível (2 ng/L). The M1 (AFM1) aflatoxin has been detected in milk from animal fed with aflatoxin B1 (AFB1) contaminated ration, with close toxic and carcinogenic effects. This is a potential a health public problem, because young individuals are among the greater milk consumers and more sensible to their effects. This study was developed to determine the aflatoxins presence in ration and AFM1 in raw and pasteurized milk. Twelve milk producers were used, and only two presented significant aflatoxin M1 values in milk. Milk samples were taken 24 hours after the collection of the ration. The method used for the aflatoxins detection was a thin layer in silica 60 G chromatography. For determination of AFM1 in milk, the immunoafinity column method was used for purification, with subsequent detection by reverse phase HPLC. The aflatoxins were not detected in ration samples, with the quantification limit being 2 µg Kg-1. In milk samples, where the quantification limit was much lower (2 ng L-1), AFM1 was detected in 19 (52,8%) from 36 raw milk samples in trace values of about 74.1 ng L-1. In pasteurized milk, the AFM1 was detected in 13 (38.2%) from 34 samples, in trace values of about 58.9 ng L-1. The aflatoxin concentrations found are within tolerated standard according to Brazilian legislation. There was no difference among the aflatoxin concentration in raw and pasteurized milk.

SummaryMultidrug-resistant tuberculosis (MDR-TB) is known as having a poor prognosis with a weak response to therapy and very high death rates. The aim of this work was to assess the immune response to the RD1-encoded antigen ESAT-6 of Mycobacterium tuberculosis in MDR-TB patients and compare to non-resistant (NR) TB patients and healthy controls (HC). Evaluation of interferon (IFN)-γ production showed that, although 55% of the MDR patients were responsive to ESAT-6, they produced lower IFN-γ levels (553 ± 11 pg/ml) when compared to NR-TB (1179 ± 163 pg/ml; P

Nesse contexto, o objetivo dessa revisão de literatura foi investigar agentes naturais por apresentarem baixa toxicidade além de serem recursos sustentáveis, viáveis para uso odontológico, que se apresentam como potenciais agentes biomodificadores. Para isso, foram selecionados artigos publicados entre os anos 2000 e 2017 na língua inglesa, usando as base de dados PubMed, Bireme e Scielo com. Foi possível constatar na literatura que agentes como as proantocianidinas (PACs), epigalocatequina-3-galato (EGCG) entre outras catequinas, resveratrol, cardol, cardanol, PA oligoméricas, genipina, hesperidina e outros polifenóis são benéficos na inativação de metaloproteinases de matriz (MMPs) e na biomodificação do colágeno podendo ser aplicados clinicamente como pré- tratamento dentinário ou incorporados ao adesivo.Palavras-chave: Crosslink. Colágeno. Polifenol.

O objetivo desta revisão de literatura foi investigar os critérios de classificação de lesões cariosas associados ao diagnóstico precoce e à técnica minimamente invasiva. Para isso, foram selecionados artigos publicados no período de 2000 a 2017, na língua inglesa, com base de dados em PUBMED e utilizando os seguintes descritores: Dental Caries, DMF index, Health services epidemiology. Dos 27 artigos encontrados foram selecionados 17 artigos que se adequavam à pesquisa. O diagnóstico precoce e correto das lesões cariosas são a chave do sucesso de tratamentos minimamente invasivos na Odontologia, apesar de que, antes de qualquer tratamento preventivo ou restaurador, há a necessidade de calibração sobre a avaliação das lesões dentárias em questão.Palavras-chave: Dental Caries. DMF Index. Health Services Epidemiology.

O objetivo da pesquisa foi comparar o efeito da Epigalocatequina-3-galato (EGCG), na forma pura e microencapsulada, incorporado ao sistema adesivo convencional e aplicado como pré-tratamento dentinário, na resistência de união à dentina. Primeiramente, realizou-se o grau de conversão (%GC) pelo Espectrofotômetro FT-IR e ensaio de liberação dos adesivos para avaliar o desempenho das micropartículas poliméricas carregadas com EGCG. Em seguida, 45 terceiros molares humanos foram divididos em 5 grupos (n9) de acordo com a solução de pré-tratamento e sistema adesivo utilizado e foram submetidos ao teste de microtração em uma máquina de ensaios universais. Não houve diferença estatística significante entre as médias do grau de conversão. (p>0,05). Em relação ao ensaio de liberação, o grupo PLGA50:50/EGCG a 1,0% apresentou melhores resultados, alcançando a maior liberação em termos quantitativos. Nenhuma diferença estatisticamente significante foi encontrada entre as médias dos valores de resistência de união (p>0,05). A incorporação das micropartículas poliméricas carregadas com EGCG não interferiu no grau de conversão dos adesivos. O sistema adesivo com micropartículas carregadas com EGCG incorporado em sua composição foi capaz de liberar EGCG. Porém, o EGCG não teve efeito estatisticamente significante quando incorporado ao sistema adesivo convencional ou aplicado como pré-tratamento da dentina, de forma pura e microencapsulada, na resistência de união imediata porém, pode aumentar a durabilidade da interface de união ao longo do tempo.Palavras-chave: Adesivos. Polímeros. Catequina. Metaloproteinases da Matriz.

To study the relationship between the sympathetic nerve activity and hemodynamic alterations in obesity, we simultaneously measured muscle sympathetic nerve activity (MSNA), blood pressure, and forearm blood flow (FBF) in obese and lean individuals. Fifteen normotensive obese women (BMI = 32.5 +/- 0.5 kg/m2) and 11 age-matched normotensive lean women (BMI = 22.7 +/- 1.0 kg/m2) were studied. MSNA was evaluated directly from the peroneal nerve by microneurography, FBF was measured by venous occlusion plethysmography, and blood pressure was measured noninvasively by an autonomic blood pressure cuff. MSNA was significantly increased in obese women when compared with lean control women. Forearm vascular resistance and blood pressure were significantly higher in obese women than in lean women. FBF was significantly lower in obese women. BMI was directly and significantly correlated with MSNA, blood pressure, and forearm vascular resistance levels, but inversely and significantly correlated with FBF levels. Obesity increases sympathetic nerve activity and muscle vascular resistance, and reduces muscle blood flow. These alterations, taken together, may explain the higher blood pressure levels in obese women when compared with lean age-matched women.

When properly applied, statistical tools are an effective way for improving process quality. Although training on statistical process control (SPC) is increasing, unfortunately it is likely to find examples where the SPC implementation does not lead to any kind of process improvement. In fact, SPC implementation is not a simple and automatic task. Frequently, the blind use of these tools causes more perplexity than value. The availability of statistical software together with the pressure for ISO 9000 registration can partially explain this situation. In this paper, the basic principles of some statistical tools are clarified, and a case-study from a ferrous castings foundry is presented, describing a situation in which the traditional inference SPC tools are not recommended. Alternatively, graphical aids are applied in order to support process management decisions.

The functioning of the immune system partially relies on T-cell exportation from the thymus, the major site of T-cell differentiation. Although the molecular mechanisms governing this process begin to be elucidated, it is not clear if thyroid hormones can alter the homing of recent thymic emigrants (RTE) to peripheral lymphoid organs. Herein, we investigated whether triiodothyronine (T(3)) could influence the homing of thymus-derived T cells. For that we used intrathymic injection of T(3) in combination with fluorescein isothiocyanate (FITC) to trace, 16 h later, FITC(+) cells, termed RTE, in peripheral lymphoid organs. We observed that T(3) stimulated thymocyte export, increasing the frequency of CD4(+) RTE and CD8(+) RTE in the subcutaneous and mesenteric lymph nodes. By contrast, the relative numbers of CD4(+) RTE in the spleen were decreased. T(3) also changed the differential distribution pattern of CD4(+) RTE, and to a lesser extent CD8(+) RTE in the peripheral lymphoid organs. Moreover, the expression of extracellular matrix (ECM) components, such as laminin and fibronectin, which are known to be involved in T-cell migration, increased in the lymph nodes but not in the spleen following intrathymic T(3) treatment. In conclusion, our data correspond to the first demonstration that in vivo treatment with thyroid hormone stimulates thymic T-cell homing and T-cell distribution in peripheral lymphoid organs.

Triiodothyronine (T(3)) exerts several effects on thymus physiology. In this sense, T(3) is known to stimulate thymic microenvironmental cells to enhance the production of extracellular matrix (ECM) moieties, which are relevant in thymocyte migration. Here, we further investigated the in vivo influence of T(3) on ECM production, as well as on ECM-related T-cell migration events. For this, BALB/c mice were subjected to two protocols of T(3) treatment: long-term (30 days) i.p. daily T(3) injections or short-term (16 h) after a single T(3) intrathymic injection. These two treatments did promote an enhancement in the expression of fibronectin and laminin, in both cortex and medullary regions of the thymic lobules. As revealed by the long-term treatment, the expression of ECM protein receptors, including VLA-4, VLA-5 and VLA-6, was also increased in thymocyte subsets issued from T(3)-treated mice. We further used thymic nurse cells (TNC) as an in vitro system to study the ECM-related migration of immature thymocytes in the context of thymic epithelial cells. Even a single intrathymic injection of T(3) resulted in an increase in the ex vivo exit of thymocytes from TNC lymphoepithelial complexes. Accordingly, when we evaluated thymocyte migration in transwell chambers pre-coated with ECM proteins, we found an increase in the numbers of migrating cells, when thymocytes were derived from T(3)-treated mice. Overall, our data show that in vivo intrathymic short-term i.p. long-term T(3) treatments are able to modulate thymocyte migration, probably via ECM-mediated interactions.

Feed contamination can lead to nutrient losses and detrimental effects on animal health and production. The purposes of this study were to investigate the mycobiota in equine mixed feeds and to determine natural contamination with aflatoxin B1 (AFB1) and fumonisin B1 (FB1). Fungal enumeration of equine feed samples was done. A commercially available enzyme-linked immunosorbent assay kit was applied to quantify AFB1 and FB1. A comparison between ELISA and HPLC was carried out. Feed mould counts ranged from1 x 10(2) to 1 x 10(5) cfu/g. The most frequent genus isolated was Aspergillus (40.54%), followed by Penicillium (18.38%) and Fusarium (16.22%). The most prevalent Aspergillus sp. was A. flavus (36%). AFB1 values ranged between 0.01 and 99.4 microg/kg. FB(1) levels ranged between 0.01 and 7.49 microg/kg. HPLC and ELISA methods showed positive correlation for AFB1 and FB1 determinations (r = 0.9851 and r = 0.9791, respectively). The ELISA analytical method was efficient for AFB1 and FB1 detection. The scarcity of studies on natural fungal contamination and on the presence of AFB1 and FB1 in materials used as equine feed ingredients highlights the value and contribution of this study.

In Brazil, commercial feedstuffs are an important component in modern animal husbandry, but there is no information available about fungal contamination and ochratoxin A (OTA) production. The aims of this study were to determine the mycoflora incidence in poultry feeds and evaluate OTA production. In addition, the ability to produce OTA by several Aspergillus and Penicillium species was investigated. A total of 96 samples of poultry feeds were collected from four factories in Rio de Janeiro. Samples were examined for total moulds, for Aspergillus and Penicillium spp. occurrence and for their relative densities on dichloran rose bengal chloramphenicol and dichloran 18% glycerol media. The capacity to produce ochratoxin A by selected Aspergillus and Penicillium species was determined by HPLC. Total mould counts were generally higher than 1 x 10(5 )CFU ml(-1). Aspergillus and Penicillium species were isolated in the highest numbers. Aspergillus flovus and Penicillium citrinum were the most prevalent species. There was a high percentage of potential OTA producers (46%). The amount of OTA produced on this substrate was enough to cause adverse effects in animals. Several strains isolated from poultry feeds were able to produce high levels of OTA on chloramphenicol yeast medium. OTA in raw materials needs to be surveyed and storage practices must be investigated to determine occurrence and establish the livestock toxicological risk in poultry feed.

We compared the genetic variation of Pinus pinaster populations using amplified fragment length polymorphism (AFLP) and chloroplast simple-sequence repeat (cpSSR) loci. Populations' levels of diversity within groups were found to be similar with AFLPs, but not with cpSSRs. The high interlocus variance associated with the AFLP loci could account for the lack of differences in the former. Although AFLPs revealed much lower genetic diversity than cpSSRs, the levels of among-population differentiation found with the two types of marker were similar, provided that loci showing fewer than four null-homozygotes, in any population, were pruned from the AFLP data. Moreover, the French and Portuguese populations were clearly differentiated from each other, with both markers. The Mantel test showed that the genetic distance matrix calculated using the AFLP data was correlated with the matrix derived from the cpSSRs. Because of the concordance found between markers we conclude that gene flow was indeed the predominant force shaping nuclear and chloroplastic genetic variation of the populations within regions, at the geographical scale studied.

Three-hundred-and-ninety-seven children aged 2-59 mo presenting to the paediatric emergency departments of five public hospitals in São Paulo, Brazil, with an acute episode of lower respiratory disease were examined. The children were classified into the following diagnostic categories: acute bronchitis, acute bronchiolitis, pneumonia, asthma, post-bronchiolitis wheezing and wheezing of uncertain aetiology. Three years after the initial study, the homes of the children diagnosed as asthmatic or as having wheezing of uncertain aetiology were visited to collect information on subsequent episodes of lower respiratory disease. This paper reports the proportional incidence of different categories of lower respiratory disease and the results of an analysis to investigate clinical features that might distinguish wheezing children between those with asthma and those with an infectious disease. The predictions made for children with wheezing of uncertain aetiology were then compared with the follow-up data. Recurrent wheezing disorders (asthma, post-bronchiolitis wheezing) were common in the study sample (47% of children). Thirty-six percent of children with an initial diagnosis of wheezing of uncertain aetiology were diagnosed as asthmatic by another doctor over the next 3 y. We were unable to identify any clinical features that were useful in identifying those children likely to be diagnosed subsequently as asthmatic.The use of a diagnostic category similar to that which we have called "wheezing of uncertain aetiology" might help to alert physicians early to the possibility of asthma without interfering in the management of the illness. Such a classification might also be useful in epidemiological investigations of the aetiology of lower respiratory diseases.

The authors analyzed twelve patients with symptomatic essential throthrombocythemia (E.T.) diagnosed from 1983 to 1991. Haemorrhagic and thrombotic phenomena were the main presenting features. Treatment consisted mostly of alpha-interferon (IFN-alpha 2b) subcutaneously in dosage ranging from 3 to 5 MU/m2 and hydroxyurea (HU) in conventional dosage. A clinical response was seen in seven patients treated with IFN-alpha 2b (4 CR and 2 PR), and in four patients treated with HU (3 CR and 1 PR). No significant side effects were observed. Our findings indicate that IFN-alpha 2b offers a non-leukaemogenic and very promising therapeutic alternative for E.T.