RESUMO
Preschool children are exposed daily to metals in their homes and at daycare centers (DCC). Metal exposure and health effects are associated even at low levels, and children comprise a group of public health concern. Nail metals have been studied for exposure biomonitoring and compared to other biological media. The aim of this study was to explore the applicability of preschool fingernail lead and cadmium as subchronic exposure biomarkers. Nail lead and cadmium levels (NLL and NCL) of 602 preschool children (age: 1-4 years) who attended 21 DCC in São Paulo, Brazil, in 2013 were analyzed. Results were compared against blood lead and cadmium levels (BLL and BCL) found in a previous study. Inductively coupled plasma mass spectrometry (ICP-MS) analyses were performed for both samples. DCC and metal contaminated sites (MCS) were georeferencing. Logistic regression tests were applied to verify associations between nail metal levels and risk factors (sex, age, maternal education, secondary smoking, DCC geographic district, vehicle flow density, relative altitude and distance between DCC and nearest MCS) (p < 0.05). BLL was stratified by exposure level (low: <5 µg.dL-1; high: >13.9 µg.dL-1; medium: ≥5 µg.dL-1 and ≤13.9 µg.dL-1) and also tested the associations in order to verify if nail lead levels are affected by exposure intensity defined by blood metals concentrations. Radius distance and relative altitude of DCC to nearest MCS were associated with high NLL and NCL. Abnormal appearance of nails was associated with high NLL and low NCL. Lead and cadmium exposure magnitude had no significant impact on NLL. NLL should only be used for initial screening, and when financial resources are scarce, especially in areas located near contaminated sites. Preschool children were co-exposed to both lead and cadmium, reinforcing the need for broader studies evaluating exposure to environmental pollutants for more than one chemical element.
Assuntos
Poluentes Ambientais , Chumbo , Biomarcadores , Brasil , Cádmio , Pré-Escolar , Exposição Ambiental , Humanos , Lactente , UnhasRESUMO
Risk factors that determine the severity of Covid-19 have not been fully elucidated. The aim of this study was to evaluate the role of coronary artery calcification (CAC) as a risk factor for death or mechanical ventilation (MV) of patients without known heart disease infected with Covid-19. We analyzed 283 consecutive in-patients with acute respiratory symptoms with chest computed tomography (chest-CT), without previous heart disease, and criteria for Covid-19 (RT-PCR positive and/or typical clinical and chest-CT findings). CAC was classified by the number of coronary segments affected as absent (0), mild (1-3), and severe calcification (more than 3). The association between CAC, CAC severity, and death or MV due to severe respiratory failure was assessed by logistic regression. The mean age was 58.7±15.7 years and 54.1% were men. Patients with CAC were older, more likely to have hypertension, and less likely to be obese. CAC was present in 75 patients (26.5%), of which 42 had a mild calcification and 33 had severe calcification, and was associated with death (OR=2.35, 95%CI: 1.01-5.48) or MV (OR=2.72, 95%CI: 1.20-6.20) adjusted for multiple confounders, with significant and increased odds ratio for the severe form of CAC (death: OR=3.70, 95%CI: 1.20-11.42; MV: OR=3.30, 95%CI: 1.09-9.95). We concluded that CAC was an independent risk factor for death or MV in Covid-19 patients without previous heart disease, particularly for those with severe calcification. CAC can be easily visualized on common chest-CT, widely used in evaluation of moderate to severe Covid-19.
Assuntos
Fatores de Risco de Doenças CardíacasRESUMO
Abstract Spatial and temporal distribution of two species of adult´s ostracods (Cyprideis sp. and Cyprideis salebrosa) were studied as a function of the rainfall patterns in the Guanabara Bay, Rio de Janeiro, Brazil. Samples were taken in ten stations, along six surveys representing three periods (Dry, Early and Late Rainy) for two years. Stations were nested in four areas (Outer, Central, EPA Guapimirim and Impacted). The bottom water (temperature, salinity, dissolved oxygen and oxygen saturation) were measured in each area to characterize the influence of seasonal variations by rainfall. Cyprideis sp. and Cyprideis salebrosa showed patterns distribution to seasonality/surveys (p = 0,002 and p <0,001, respectly). The spatial distribution of Cyprideis sp was significantly different areas studied (p <0.001) indicated well defined areas and distribution in along of the surveys. However, C. salebrosa showed homogeneous distribution in along of the areas within of each survey (p <0.001). Redundancy Analysis (RDA) for the two years evidenced environment preference of the Cyprideis sp. for areas with marine conditions (high influence for channel central) and C. salebrosa for brackish water (high influence of the rivers). This observation reinforces of the existence of areas created by the seasonality of pluviometric regime, a possible dispersion of the adult's ostracods and possibility the use with bioindicators.
Resumo A distribuição espacial e temporal de duas espécies de ostracodes adultos (Cyprideis sp. e Cyprideis salebrosa) foi estudada em função do padrão pluviométrico na Baía de Guanabara, Rio de Janeiro, Brasil. As amostras foram coletadas em dez estações ao longo de seis campanhas, representando três períodos (Seco, Pré e Pós Chuvoso) por dois anos. As estações foram agrupadas em quatro áreas (Externo, Central, EPA Guapimirim e Impactado). A água do fundo (temperatura, salinidade, oxigênio dissolvido e saturação de oxigênio) foi medida em cada área para caracterizar a influência das variações sazonais pela chuva. Cyprideis sp. e Cyprideis salebrosa mostrou distribuição de padrões para sazonalidade/campanhas (p = 0,002 e p <0,001, respctivamente). A distribuição espacial de Cyprideis sp. foi significativamente diferente das áreas estudadas (p <0,001) indicou áreas bem definidas e distribuição ao longo das campanhas. No entanto, C. salebrosa mostrou distribuição homogênea ao longo das áreas dentro de cada campanha (p <0,001). A Análise de Redundância (RDA) para os dois anos evidenciou a preferência ambiental dos Cyprideis sp. para áreas com condições marinhas (alta influência para o canal central) e C. salebrosa para águas salobras (alta influência dos rios). Essa observação reforça a existência de áreas criadas pela sazonalidade do regime pluviométrico, uma possível dispersão dos adultos de ostracodes e a possibilidade do uso como bioindicadores.
Assuntos
Animais , Estuários , Baías , Brasil , Crustáceos , RiosRESUMO
Stromal/stem cell differentiation is controlled by a vast array of regulatory mechanisms. Included within these are methods of mRNA gene regulation that occur at the level of epigenetic, transcriptional, and/or posttranscriptional modifications. Current studies that evaluate the posttranscriptional regulation of mRNA demonstrate microRNAs (miRNAs) as key mediators of stem cell differentiation through the inhibition of mRNA translation. miRNA expression is enhanced during both adipogenic and osteogenic differentiation; however, the mechanism by which miRNA expression is altered during stem cell differentiation is less understood. Here we demonstrate for the first time that adipose-derived stromal/stem cells (ASCs) induced to an adipogenic or osteogenic lineage have differences in strand preference (-3p and -5p) for miRNAs originating from the same primary transcript. Furthermore, evaluation of miRNA expression in ASCs demonstrates alterations in both miRNA strand preference and 5'seed site heterogeneity. Additionally, we show that during stem cell differentiation there are alterations in expression of genes associated with the miRNA biogenesis pathway. Quantitative RT-PCR demonstrated changes in the Argonautes (AGO1-4), Drosha, and Dicer at intervals of ASC adipogenic and osteogenic differentiation compared to untreated ASCs. Specifically, we demonstrated altered expression of the AGOs occurring during both adipogenesis and osteogenesis, with osteogenesis increasing AGO1-4 expression and adipogenesis decreasing AGO1 gene and protein expression. These data demonstrate changes to components of the miRNA biogenesis pathway during stromal/stem cell differentiation. Identifying regulatory mechanisms for miRNA processing during ASC differentiation may lead to novel mechanisms for the manipulation of lineage differentiation of the ASC through the global regulation of miRNA as opposed to singular regulatory mechanisms.
Assuntos
Tecido Adiposo/citologia , Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/biossíntese , Células Cultivadas , HumanosRESUMO
Abstract Spatial and temporal distribution of two species of adult´s ostracods (Cyprideis sp. and Cyprideis salebrosa) were studied as a function of the rainfall patterns in the Guanabara Bay, Rio de Janeiro, Brazil. Samples were taken in ten stations, along six surveys representing three periods (Dry, Early and Late Rainy) for two years. Stations were nested in four areas (Outer, Central, EPA Guapimirim and Impacted). The bottom water (temperature, salinity, dissolved oxygen and oxygen saturation) were measured in each area to characterize the influence of seasonal variations by rainfall. Cyprideis sp. and Cyprideis salebrosa showed patterns distribution to seasonality/surveys (p = 0,002 and p 0,001, respectly). The spatial distribution of Cyprideis sp was significantly different areas studied (p 0.001) indicated well defined areas and distribution in along of the surveys. However, C. salebrosa showed homogeneous distribution in along of the areas within of each survey (p 0.001). Redundancy Analysis (RDA) for the two years evidenced environment preference of the Cyprideis sp. for areas with marine conditions (high influence for channel central) and C. salebrosa for brackish water (high influence of the rivers). This observation reinforces of the existence of areas created by the seasonality of pluviometric regime, a possible dispersion of the adults ostracods and possibility the use with bioindicators.
Resumo A distribuição espacial e temporal de duas espécies de ostracodes adultos (Cyprideis sp. e Cyprideis salebrosa) foi estudada em função do padrão pluviométrico na Baía de Guanabara, Rio de Janeiro, Brasil. As amostras foram coletadas em dez estações ao longo de seis campanhas, representando três períodos (Seco, Pré e Pós Chuvoso) por dois anos. As estações foram agrupadas em quatro áreas (Externo, Central, EPA Guapimirim e Impactado). A água do fundo (temperatura, salinidade, oxigênio dissolvido e saturação de oxigênio) foi medida em cada área para caracterizar a influência das variações sazonais pela chuva. Cyprideis sp. e Cyprideis salebrosa mostrou distribuição de padrões para sazonalidade/campanhas (p = 0,002 e p 0,001, respctivamente). A distribuição espacial de Cyprideis sp. foi significativamente diferente das áreas estudadas (p 0,001) indicou áreas bem definidas e distribuição ao longo das campanhas. No entanto, C. salebrosa mostrou distribuição homogênea ao longo das áreas dentro de cada campanha (p 0,001). A Análise de Redundância (RDA) para os dois anos evidenciou a preferência ambiental dos Cyprideis sp. para áreas com condições marinhas (alta influência para o canal central) e C. salebrosa para águas salobras (alta influência dos rios). Essa observação reforça a existência de áreas criadas pela sazonalidade do regime pluviométrico, uma possível dispersão dos adultos de ostracodes e a possibilidade do uso como bioindicadores.
RESUMO
MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression through targeting and suppression of mRNAs. miRNAs have been under investigation for the past twenty years and there is a large breadth of information on miRNAs in diseases such as cancer and immunology. Only more recently have miRNAs shown promise as a mechanism for intervention with respect to diseases of the bone and adipose tissue. In mesenchymal stem cell (MSC) differentiation, alterations in miRNA expression patterns can differentially promote an osteogenic, adipogenic, or myogenic phenotype. This manuscript reviews the current literature with respect to miRNAs in the context of MSC function with a particular focus on novel avenues for the examination of miRNA associated with bone and adipose tissue biology and disease. Specifically we highlight the need for a greater depth of investigation on MSCs with respect to miRNA biogenesis, processing, strand selection, and heterogeneity. We discuss how these mechanisms facilitate both altered miRNA expression and function.
Assuntos
Tecido Adiposo/metabolismo , Osso e Ossos/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Transcriptoma , Adipogenia , Tecido Adiposo/patologia , Animais , Osso e Ossos/patologia , Humanos , Células-Tronco Mesenquimais/patologia , Desenvolvimento Muscular , OsteogêneseRESUMO
No cultivo de plantas medicinais as condições de salinidade e de luz podem exercer influência no rendimento e na qualidade final da produção de biomassa. O objetivo deste trabalho foi avaliar o efeito de diferentes luminosidades e níveis de salinidade na água de irrigação sobre o crescimento e tolerância de três espécies de plantas do gênero Plectranthus. O ensaio foi conduzido em parcelas subsubdivididas com cinco repetições, sendo as parcelas referente ao fator ambiente (pleno sol e telado), as subparcelas aos níveis de salinidade na água de irrigação - CEa (0,7; 1,9; 3,1; 4,3 e 5,5 dS m-1), e as subsubparcelas às três espécies do gênero Plectranthus (P. amboinicus, P. barbatus e P. grandis). As variáveis de resposta foram: índice relativo de clorofila (IRC), área foliar (AF), razão de área foliar (RAF), área foliar específica (AFE), matéria seca da parte aérea (MSPA), matéria seca das raízes (MSR), matéria seca total (MST), relação MSR/MSPA, grau de tolerância à salinidade, e teor dos íons Na+ e K+. O estresse salino reduziu o crescimento das plantas, sendo as maiores reduções observadas nas plantas expostas a pleno sol. A salinidade influenciou a partição de matéria seca, sendo as raízes mais afetadas do que a parte aérea. Com o aumento da CEa houve aumento expressivo no teor foliar de Na+, enquanto o teor de K+ e o IRC foram reduzidos. Entretanto, o acúmulo de Na+ foi menor em P. grandis. Considerando-se a MST, verificou-se que as três espécies se mostraram moderadamente tolerantes à salinidade de até 3,1 dS m-1, exceto P. grandis cultivada em telado, classificada como tolerante. Em relação ao grau de redução na produção MSPA (parte de interesse comercial), poderia se recomendar o cultivo de P. grandis quando a água de irrigação contiver CEa de até 3,1 dS m-1.
In the cultivation of medicinal plants, salinity and light can affect the yield and quality of biomass. The objective of this study was to evaluate the effect of light and salinity levels of the irrigation water on the growth and salt tolerance of three medicinal plant species of the genus Plectranthus. A completely randomized split-plot design with five repetitions was used. The plots were formed by the environment of cultivation (full sunlight and greenhouse), the subplots by the salinity in the irrigation water - ECw (0.7, 1.9, 3.1, 4.3 and 5.5 dS m-1), and the subsubplots by the three plant species (P. amboinicus, P. barbatus and P. grandis). The following variables were evaluated: relative chlorophyll index (RCI), leaf area (LA), leaf area ratio (LAR), specific leaf area (SLA), shoot dry mass (SDM), root dry mass (RDM), total dry mass (TDM), RDM/SDM ratio, relative salt tolerance, and concentration of Na+ and K+ in leaves. Salinity reduced plant growth, with the greatest reductions observed in plants exposed to full sunlight. Salinity affected the dry matter partitioning, and the roots were more affected than the shoot. With increasing ECw, there was a significant increase in the concentration of Na+ in the leaves, while K+ and RCI decreased. However, the increase in Na+ accumulation was lower in P grandis. The three species were moderately tolerant to salinity up to 3.1 dS m-1, considering the total dry mass production, except the P. grandis grown in greenhouse, classified as tolerant. Regarding the relative reduction in shoot dry mass (part of commercial interest), we could recommend the cultivation of P. grandis when the available irrigation water presents values of ECw up to 3.1 dS m-1.
Assuntos
Radiação/classificação , Plectranthus/crescimento & desenvolvimento , Salinidade , Biomassa , /análise , Irrigação Agrícola/instrumentação , Íons/farmacologiaRESUMO
In order to study the morphological changes that occur in cells of the testes of isogenic black mouse C57BL/6/Uni into three periods during spermatogenetic used 15 mice divided into 3 groups of 5 animals with 40, 50 and 60 days of age. The mice were sacrificed and weighed. Testicles were weighed and measured, and histologically processed and stained with HE, PAS and Masson Massom-H and evaluated under light microscopy. It was observed that group I with 40 days of age in the seminiferous tubules had a lumen with sparse small amount of interstitial tubular cells. In the seminiferous epithelium type A spermatogonia, intermediate and B were identified, which occupied the compartment adbasal and intermingled with these cells in spermatocytes I in Pachytene and leptotene was observed, whereas in the adluminal compartment Golgi phase spermatids we observed the presence of acrosomal granule. In group II, the cells of the seminiferous epithelium were developed and it was observed in round spermatids cephalic hood phase plus many elongated spermatids in acrosome phase and Sertoli cells. In group III, 60 days old, it was found that seminiferous epithelium which was of the tubules had elongated spermatids in acrosome phase and maturation, with elongated nuclei and acrosomal system typical of spermiation in the presence of sperm and residual bodies near the tubular lumen. Therefore morphological evolution of germ cell testicular spermatids can be checked and recognized in its four phases: golgi, cap, acrosome and maturation over the age of the animal.
Con el fin de estudiar los cambios morfológicos que ocurren en las células de los testículos del ratón negro isogénico C57BL/6/Uni en tres períodos durante el proceso espermatogenético, se utilizaron 15 ratones divididos en 3 grupos de 5 animales con 40, 50 y 60 días de edad. Los ratones fueron sacrificados y pesados. Luego se pesaron y midieron los testículos, para ser finalmete procesados histológicamente y teñidos con HE, PAS y tricrómico Massom-H y evaluados bajo microscopía de luz. Se observó en el grupo I con 40 días de edad que los túbulos seminíferos tenían un lumen pequeño con escaza cantidad de células tubulares intersticiales. En el epitelio seminífero se identificaron espermatogonias tipo A, intermedio y B, que ocuparon el compartimiento adbasal y entremezcladas con estas células, se observó los espermatocitos I en paquiteno y leptoteno, mientras que en el compartimiento adluminal se observaron espermátidas de fase Golgi en presencia de gránulos acrosomales. En el grupo II, las células del epitelio seminífero se desarrollaron y fue posible observar espermátidas redondas en fase de capuz cefálico además de numerosas espermátidas elongadas en fase acrosómica y células sustentaculares. En el grupo III, de 60 días de edad, se encontró que el epitelio seminífero que revestía los túbulos presentaban espermátidas alargadas en fase acrosómica y de maduración, con sus núcleos alargados y el sistema acrosomal típico de la espermiación, con la presencia de espermatozoides y cuerpos residuales cerca del lumen tubular. Así, se puede comprobar con el paso de la edad del animal, la evolución morfológica de las células germinativas testiculares y reconocer las espermátidas en sus cuatro fases: golgi, capuchón, acrosomal y de maduración.
Assuntos
Animais , Ratos , Células Intersticiais do Testículo , Maturidade Sexual , Espermatogênese , Testículo/anatomia & histologia , Testículo/citologia , Testículo/ultraestruturaRESUMO
In order to study the morphological changes that occur in cells of the testes of isogenic black mouse C57BL/6/Uni into three periods during spermatogenetic used 15 mice divided into 3 groups of 5 animals with 40, 50 and 60 days of age. The mice were sacrificed and weighed. Then weighed and measured the testicles, to be processed finalmete histologically and stained with HE, PAS and Masson Massom-H and evaluated under light microscopy. Was observed in group I with 40 days of age in the seminiferous tubules had a lumen with sparse small amount of interstitial tubular cells. In the seminiferous epithelium were identified type A spermatogonia, intermediate and B, which occupied the compartment adbasal and intermingled with these cells was observed in spermatocytes I in Pachytene and leptotene, whereas in the adluminal compartment Golgi phase spermatids observed in the presence of acrosomal granule. In group II, the cells of the seminiferous epithelium were developed and it was observed in round spermatids cephalic hood phase plus many elongated spermatids in acrosome phase and Sertoli cells. In Group III, 60 days old, it was found that the seminiferous epithelium which was of the tubules had elongated spermatids in acrosome phase and maturation, with elongated nuclei and acrosomal system typical of spermiation in the presence of sperm and residual bodies near the tubular lumen. So you can check the morphological evolution of germ cell testicular spermatids and recognize its four phases: Golgi, cap, acrosome and maturation over the age of the animal.
Con el fin de estudiar los cambios morfológicos que ocurren en las células del testículo del ratón negro isogénico C57BL/6/Uni en tres períodos diferentes del proceso espermatogenético; fueron utilizados 15 ratones divididos en 3 grupos (n=5) con 40, 50 y 60 días de edad respectivamente. Todos los animales fueron sacrificados y pesados. Posteriormente sus testículos se pesaron, midieron y procesaron histológicamente para HE, PAS y tricrómico Massom-H. Las muestras obtenidas fueron evaluados con microscopía de luz. En el grupo I con 40 días se observaron túbulos seminíferos con un lúmen pequeño y escaza cantidad de células intersticiales. En el epitelio seminífero se identificaron espermatogonias tipo A, intermedio y B, quienes ocuparon el compartimiento basal entremezclándose con espermatocitos I en paquiteno y leptoteno. En el compartimiento adluminal se observaron espermatidas de fase Golgi y presencia de gránulos acrosomales. En el grupo II de 50 días, se observaron células del epitelio seminífero desarrolladas, espermatidas en fase de capuz cefálico, muchas espermatidas elongadas en fase acrosomica y células sustentaculares. En el Grupo III de 60 días se observó el epitelio del túbulo seminífero con espermátidas alargadas en fase acrosómica y de maduración, con núcleos alargados y un sistema acrosomal típico de la espermiación, con presencia de espermatozoides y cuerpos residuales cerca del lúmen tubular. En conclusión se observa la evolución morfológica de las células germinativas testiculares y se reconocen las espermatides en sus cuatro fases: Golgi, capuchón, acrosomal y de maduración en las diferentes edades del animal.
Assuntos
Ratos , Espermatogênese , Testículo/anatomia & histologia , Testículo/citologia , Testículo/ultraestrutura , Camundongos Endogâmicos/anatomia & histologiaRESUMO
Os dados são provenientes de 234 touros da raça Nelore participantes de um teste de progênie, no período de 1996 a 2003. A diferença esperada na progênie (DEP) de sete características: peso aos 120 e 210 dias, efeito materno (DMPP120 e DMPP210), peso e perímetro escrotal aos 365 e 450 dias, efeito direto (DDP365, DDP450, DDPE365 e DDPE450) e idade ao primeiro parto (DDIPP) foi utilizada para classificar os animais em três grupos, assim como identificar quais as características possuíram maior poder discriminatório na formação de cada grupo. Para tanto, foram utilizados procedimentos estatísticos multivariados de análise de agrupamentos k-médias e componentes principais. Os resultados evidenciaram que, dos três grupos formados, dois se destacaram quanto aos valores médios das DEPs. A importância desses dois grupos de touros foi confirmada pela análise de componentes principais, que associou a eles valores superiores de DEPs diretas de peso e perímetro escrotal. A quantidade da variabilidade original retida pelos dois primeiros componentes principais foi de 70,22 por cento. Estes procedimentos mostraram-se eficientes e constituíram importantes ferramentas para classificar touros, discriminar variáveis, bem como resumir informações multivariadas, podendo ser usados como auxílio valioso na seleção de reprodutores para uso nos programas de melhoramento genético.
The data set is from 234 Nelore bulls which participate of a progeny test in the period from 1996 to 2003. The expected progeny diference (EPDs) of seven economic traits, weights at 120 e 210 days of age, maternal effect (DMPP120 and DMPP210), weights and scrotal circumferences at 365 e 450 days of age, direct effects (DDP365, DDP450, DDPE365 and DDPE450), and age at first calving (DDIPP), were used in order to classify these animals in three groups and verify which EPDs showed greatest discriminating power in forming the groups. The statistical applied techniques were: k-means clusters analysis and principal components analysis. From the three groups formed, two of them stood out in relation to values of the EPDs means. Evidence of the importance of these two groups was observed in the principal component analysis that associate to them higher values of direct EPDs of weight and scrotal circumference. The two first principal components accounted for 70.22 percent of the total original variability. Both techniques could be an important tools to sire classification, variable discrimination, as well as to resume multivariate information, and they could be applied to help selection in animal breeding program.
Assuntos
Animais , Bovinos/anatomia & histologia , Variação Genética , Melhoramento Genético/métodosRESUMO
Compararam-se os custos de seis esquemas de controle leiteiro (CL), estabelecidos com base em diferentes freqüências de controles (com possibilidade de controle trimestral supervisionado e aproveitamento do CL da fazenda), no número de ordenhas e na realização de análises qualitativas (composição do leite e/ou contagem de células somáticas). Computaram-se os percentuais que os custos totais do CL representariam na receita bruta mensal do leite (CL/RB) e na receita líquida mensal (CL/RL). O esquema tradicional (freqüência mensal) apresentou o mais elevado custo mensal e os maiores CL/RB e CL/RL. Esquemas com intervalo maior entre controles e amostragem em ordenhas alternadas resultaram na redução dos custos com diárias e quilometragem. O custo mensal do CL variou de 0,68% a 1,8% sobre a receita bruta do leite e de 6,6% a 17,0% sobre a receita líquida.
Assuntos
Animais , Feminino , Bovinos , Bovinos , Leite/economia , Leite/normas , Contagem de Células/normasRESUMO
In this study, a single-step duplex polymerase chain reaction procedure was developed for rapid, specific and sensitive identification of Entamoeba histolytica and for its diagnostic differentiation from E. dispar. Specific oligonucleotide primers were combined for the amplification of a cysteine proteinase 5 gene target sequence of 242 bp, present only in E. histolytica. Additionally, another oligonucleotide primer pair for both the E. histolytica and E. dispar actin gene target of 300 bp was designed to amplify only from amoebae DNA. The PCR developed was specific and efficiently identified and differentiated these parasites from each other in either cultured parasites or from stool material.
Assuntos
Disenteria Amebiana/parasitologia , Entamoeba histolytica/genética , Reação em Cadeia da Polimerase/métodos , Actinas/química , Actinas/genética , Animais , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , DNA de Protozoário/química , DNA de Protozoário/genética , Entamoeba histolytica/classificação , Entamoeba histolytica/enzimologia , Fezes/parasitologia , Humanos , Especificidade da EspécieRESUMO
Foram analisados dados de peso, altura e desempenho produtivo e reprodutivo de 1.272 novilhas da raça Holandesa, nascidas no período de 1990 a 1998. Estudaram-se o desenvolvimento em peso e altura do nascimento até o primeiro parto, as características peso ao primeiro parto (PP), idade ao primeiro parto (IP), produção de leite na primeira lactação (PL), primeiro intervalo de partos (IEP), e os parâmetros genéticos pertinentes. As equações para as curvas de peso e altura, estimadas pelo modelo proposto por von Bertalanffy, foram: Yi= 802,10 (1 - 0,630EXP (-0,0022t)) e Yi= 1,40 (1 - 0,208EXP (-0,0038t)), respectivamente. As novilhas atingiram o primeiro parto com altura média de 140cm e peso de 602kg aos 27 meses de idade. A produção total de leite na primeira lactação foi de 8.026kg e o primeiro IEP 420 dias. Na obtenção dos componentes de (co)variância utilizou-se o método da máxima verossimilhança restrita livre de derivada. As estimativas de herdabilidade foram 0,31, 0,35 e 0,34, respectivamente, para PP, IP e PL, e 0,10 para IEP, evidenciando variância genética aditiva média para as três primeiras características. As correlações genéticas apresentaram pequena magnitude para PP e PL, PL e IP, e IEP e PL. A correlação entre IEP e PP foi 0,49; entre IEP e IP o valor foi negativo, -0,69, indicando provável antagonismo entre as duas últimas características.
Assuntos
Animais , Feminino , Bovinos/crescimento & desenvolvimento , Bovinos/genética , Crescimento , Leite/provisão & distribuição , Peso ao Nascer/genética , Moldes GenéticosRESUMO
OBJETIVOS: Apresentar a experiência de um trabalho comunitário em creche de 410 crianças, vinculada a uma instituiçäo católica e que se constitue em aulas práticas da disciplina Políticas de Saúde em curso de graduaçäo em medicina. MÉTODOS: Através de conversa informal e brincadeiras, realiza-se observaçäo clínico-epidemiológica e levantamento de necessidades de saúde de crianças de três meses a seis anos. RESULTADOS: Foram diagnosticados quatro temas relevantes para a clientela : higiene, saúde bucal, saúde ocular e dependência química em pessoas da família. Para abordar essas questöes, organizou-se evento educativo interativo constituído de dramatizaçäo; gincana; filme e laboratório com peças anatômicas artificiais. CONCLUSÖES: Essas atividades proporcionaram oportunidade ao acadêmico de medicina de vivenciar uma realidade social até entäo pouco conhecida, e trabalhar sentimentos e compromisso com a saúde no nível coletivo
Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Ensino , Creches , Educação em Saúde , Promoção da Saúde , Higiene , Saúde Bucal , Saúde da Família , Relações Comunidade-Instituição , Transtornos Relacionados ao Uso de SubstânciasRESUMO
The conformational dependence of the gas-phase hydrogen/deuterium (H/D) exchange of nucleotide-5-monophosphate anions with the H/D exchange reagent D2S is reported here. The electrospray-generated [M-H]- anions of adenosine-5'-monophosphate, adenosine-5'-carboxylic acid, ribitol-5-phosphate, and 2-deoxy-ribitol-5-phosphate were reacted with D2S in the gas phase. Their reactivity (adenosine-5'-monophosphate exchanged 2 of 5 labile hydrogens, adenosine-5'-carboxylic acid exchanged 1 of 4, ribitol-5-phosphate exchanged 2 of 3, and 2-deoxy-ribitol-5-phosphate exchanged 1 of 2) suggests that the hydroxyl group in the 2 position of the ribose sugar and the amino hydrogen on the nucleobase do not exchange readily with D2S. Semiempirical molecular orbital calculations suggest that the labile hydrogens in these positions are thermodynamically facile to exchange but as a conformation inaccessible to the presumed phosphate anion, consistent with a mechanism in which the phosphate anion complexes with the exchange reagent and assists H/D exchange at a neighboring site.
Assuntos
Adenosina/química , AMP Cíclico/química , DNA/química , RNA/química , Adenosina/análogos & derivados , Monofosfato de Adenosina/análise , Modelos Moleculares , Conformação de Ácido Nucleico , Ribitol/química , Espectroscopia de Infravermelho com Transformada de Fourier , TermodinâmicaRESUMO
The gas-phase structures of protonated (deoxy)nucleoside-5'- and 3'-monophosphates (mononucleotides) have been examined by the use of gas-phase hydrogen/deuterium (H/D) exchange and high-field Fourier-transform ion cyclotron resonance mass spectrometry. These nucleotides were reacted with three different deuterating reagents: ND3, D2O, and D2S, of which ND3 was the most effective. All mononucleotides fully exchanged their labile hydrogen for deuterium with ND3 with the exception of deoxycytidine-3'-monophosphate, deoxyadenosine-5'-monophosphate, adenosine-5'-monophosphate, and adenosine-3'-monophosphate. Semiempirical calculations demonstrate the presence of hydrogen bonding upon protonation of the purine mononucleotides which may lead to incomplete H/D exchange. H/D exchange rates differed between the deoxymononucleotides and the ribomononucleotides, suggesting that the 2'-OH group plays an important role in the exchange process. Reactions of nucleosides and mononucleotides with D2O demonstrate that a structure-specific long-lived ion-molecule complex between D2O and the mononucleotide involving the phosphate group is necessary for exchange to overcome the high-energy activation barrier. In contrast, a structure-specific long-lived ion-molecule complex between the mononucleotides and ND3 is not required for exchange to occur.
Assuntos
Nucleotídeos/química , Ciclotrons , Deutério/química , Análise de Fourier , Hidrogênio/química , Cinética , Modelos Moleculares , Pirimidinas/química , Espectrometria de Massas por Ionização por Electrospray , TermodinâmicaRESUMO
No presente estudo foram utilizados 17.968 registros de produçäo de leite, referentes a 2.130 primeiras lactaçöes de vacas da raça Holandesa, paridas nos anos de 1988 a 1991, filhas de 136 touros e controladas pela Associaçäo Brasileira de Criadores (ABC). Os dados foram distribuídos em dez sub-arquivos de acordo com o número do controle (M1 e M10). As características estudadas foram: produçäo de leite no dia do controle (M) e produçäo aos 305 dias de lactaçäo (M305), as quais foram ajustadas para os seguintes fatores de variaçäo: idade da vaca ao parto em classes, intervalo parto-primeiro controle e subclasses de rebanho-ano-estaçäo de parto. Os componentes de (co)variância foram obtidos a partir de análises com duas características utilizando-se o método REML, sob um modelo de touro. As estimativas de herdabilidade para as M variaram de 0,04 a 0,32 sendo os maiores valores encontrados na segunda fase da lactaçäo (M5 a M7), enquanto que para a M305 este valor foi de 0,32. As correlaçöes genéticas entre as M e a M305 variaram de 0,78 a 1,00. Os resultados sugerem que as M podem ser utilizadas em substituiçäo à M305 nas avaliaçöes genéticas dos animais, visto que as herdabilidades no meio da lactaçäo foram semelhantes à encontrada para a M305. Além disso, a seleçäo antecipada pode levar a uma reduçäo no intervalo de geraçöes.
Assuntos
Animais , Bovinos/genética , LeiteRESUMO
The authors report a clinical case of a 60-year-old Caucasian man, with two episodes of arterial embolization in the lower limbs. A microscope investigation of the emboli revealed that they originated from fungal aortitis caused by Paracoccidioides brasiliensis. A review of aortic infections showed only one similar report of this rare clinical expression of blastomycosis. The authors suggest a routine postoperative search for emboli followed by culture and histopathology.
Assuntos
Aortite/microbiologia , Perna (Membro)/irrigação sanguínea , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/microbiologia , Artéria Poplítea , Tromboembolia/microbiologia , Angiografia , Aortite/diagnóstico por imagem , Embolectomia , Evolução Fatal , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Paracoccidioidomicose/diagnóstico por imagem , Tromboembolia/diagnóstico por imagem , Tromboembolia/cirurgia , Tomografia Computadorizada por Raios XRESUMO
The gas-phase reactions of the nitrosonium ion, NO+ with the amino acids glycine, alanine and valine and their N-methyl derivatives were investigated under chemical ionization mass spectrometric (CIMS) conditions. Two products were observed in all cases: the formation of the iminium ion and the formation of an [M-H]+ ion. The latter product is consistent with a reaction channel involving hydride abstraction by NO+, and was confirmed by (i) examining the Ar+CI mass spectra of the same amino acids under similar source conditions and (ii) examining the unimolecular fragmentation reactions of the [M + H]+ ions of the N-nitroso-N-methyl derivatives of each of the amino acids in a tandem mass spectrometer. Further insights into the reaction of glycine with NO+ were obtained by performing ab initio calculations (at the MP2/6-31G* parallel HF/6-31G* level). These results indicate that four reactions are thermodynamically viable for glycine: (i) hydride abstraction; (ii) iminium ion formation (with concomitant loss of HONO and CO); (iii) diazonium ion formation; and (iv) diazonium ion formation followed by loss of N2. Possible reasons why reactions (iii) and (iv) are not observed are discussed, and comparisons with solution reactivity and the gas-phase reactivity of NO+ are also made.
Assuntos
Alanina/química , Glicina/química , Compostos Nitrosos/química , Valina/química , Gases , Indicadores e Reagentes , Espectrometria de Massas , Metilação , Conformação Molecular , TermodinâmicaRESUMO
We used quantitative cell transplantation to evaluate the frequencies of the formation of radiogenic thyroid cancer per clonogenic rat thyroid epithelial cell in vivo. Irradiation of thyroid cells with 5 Gy 137Cs gamma rays before transplantation significantly increased the incidence of thyroid carcinoma formation in such grafts compared to similar grafts of unirradiated thyroid cells. We calculated the frequencies of radiogenic cancer by subtracting cancer incidences in unirradiated groups from incidences in irradiated groups and dividing by the number of clonogens grafted. The highest observed frequencies of radiogenic thyroid cancer so calculated were 0.141 and 0.046 cancers per surviving irradiated clonogenic cell. These cancer frequencies occurred in grafts containing averages of three and ten clonogens per site, respectively, and represent one cancer per approximately 7 and approximately 22 irradiated clonogens. We conclude that the highest observed frequencies of radiogenic cancer are likely to be the best estimates of the "real" frequency per irradiated clonogen in that virtually all the methodological sources of inaccuracy tend to decrease the observed frequency compared to the "real" frequency. Radiogenic initiation of cancer is thus a highly common cellular event among surviving irradiated clonogenic thyroid cells. To examine the role of endocrine-mediated tumor promotion on the expression of radiogenic cancer, we attenuated the intensity of thyrotropin (TSH)-mediated tumor promotion in some groups of recipient animals. We found that the incidence rates for radiation-associated cancer were significantly higher in rats with higher serum TSH levels compared to rats with lower TSH levels. We conclude from these data that (1) radiogenic thyroid cancer occurs with a high frequency and (2) chronic TSH stimulation accelerates progression of radiogenic neoplasms to overt carcinomas and promotes development of later-arising carcinomas in grafts of unirradiated thyroid clonogens.