Compounds used to produce cloned animals are genotoxic and mutagenic in mammalian assays in vitro and in vivo

The compounds 6-dimethylaminopurine and cycloheximide promote the successful production of cloned mammals and have been used in the development of embryos produced by somatic cell nuclear transfer. This study investigated the effects of 6-dimethylaminopurine and cycloheximide in vitro, using the thiazolyl blue tetrazolium bromide colorimetric assay to assess cytotoxicity, the trypan blue exclusion assay to assess cell viability, the comet assay to assess genotoxicity, and the micronucleus test with cytokinesis block to test mutagenicity. In addition, the comet assay and the micronucleus test were also performed on peripheral blood cells of 54 male Swiss mice, 35 g each, to assess the effects of the compounds in vivo. The results indicated that both 6-dimethylaminopurine and cycloheximide, at the concentrations and doses tested, were cytotoxic in vitro and genotoxic and mutagenic in vitro and in vivo, altered the nuclear division index in vitro, but did not diminish cell viability in vitro. Considering that alterations in DNA play important roles in mutagenesis, carcinogenesis, and morphofunctional teratogenesis and reduce embryonic viability, this study indicated that 6-dimethylaminopurine and cycloheximide utilized in the process of mammalian cloning may be responsible for the low embryo viability commonly seen in nuclear transfer after implantation in utero.

Morphological features of pycnodysostosis with emphasis on clinical and radiographic maxillofacial findings / Características morfológicas de la picnodisostosis con énfasis en hallazgos clínicos y radiológicos maxilofaciales

Pycnodysostosis is a rare genetic syndrome characterized by short stature, obtuse mandibular angle, frontal, parietal and occipital bossing, open fontanels and cranial sutures, midfacial hypoplasia, acro-osteolysis of the distal phalanges, increased bone density, absence or hipopneumatization of the paranasal sinuses and normal laboratory studies. We report the case of a 35-year-old Brazilian man that was referred to a private clinic with history of dysmorphic facies for evaluation. The clinical and radiological features exhibited by the patient led to a diagnosis of pycnodysostosis. We describe the morphological features of pycnodysostosis with emphasis on the clinical and radiographic maxillofacial findings comparing the data obtained from our case with a literature review.

La picnodisostosis es un síndrome genético raro caracterizado por baja estatura, ángulo de la mandíbula obtuso, prominencias frontal, parietal y occipital, suturas craneales y fontanelas abiertas, hipoplasia del tercio medio de la cara, acroosteolisis de las falanges distales, aumento de la densidad ósea, ausencia o hiponeumatización de los senos paranasales y exámenes de laboratorio normales. Se presenta un caso de paciente brasileño, 35 años de edad, sexo masculino, remitido a clínica privada con historia de facies dismórfico para evaluación. Las características clínicas y radiológicas exhibidas por el paciente llevaron al diagnóstico de picnodisostosis. Se describe las características morfológicas de la picnodisostosis con énfasis en los hallazgos clínicos y radiológicos maxilofaciales, comparando los datos obtenidos en nuestro caso con los hallazgos reportados en la literatura revisada.

Identification of sarcopenic obesity in postmenopausal women: a cutoff proposal

Sarcopenic obesity is the combination of reduced fat-free mass (FFM) and increased fat mass (FM) with advancing age but there is lack of clear criteria for its identification. The purposes of the present investigation were: 1) to determine the prevalence of postmenopausal women with reduced FFM relative to their FM and height, and 2) to examine whether there are associations between the proposed classification and health-related variables. A total of 607 women were included in this cross-sectional study and were separated into two subsets: 258 older women with a mean age of 66.8 ± 5.6 years and 349 young women aged 18-40 years (mean age, 29.0 ± 7.5 years). All volunteers underwent body composition assessment by dual-energy X-ray absorptiometry. The FFM index relative to FM and height was calculated and the cutoff value corresponded to two standard deviations below the mean of the young reference group. To examine the clinical significance of the classification, all older participants underwent measurements of quadriceps strength and cardiorespiratory fitness. Values were compared between those who were classified as low FFM or not, using an independent samples t-test and correlations were examined. The cutoff corresponded to a residual of -3.4 and generated a sarcopenic obesity prevalence of 19.8 percent that was associated with reduced muscle strength and aerobic fitness among the older participants. Also, the index correlated significantly with the health-related fitness variables. The results demonstrated reduced functional capacity for those below the proposed cutoff and suggested applicability of the approach as a definition for sarcopenic obesity.

Inhibition of Gelatinases by Vegetable Extracts of the Species Tapirira guianensis (Stick Pigeon).

Tapirira guianensis (Stick pigeon), a widely-used herbal medicine, has been reported to possess various biological activities. The aim of this study was the phytochemical analysis of the fractions of extracts of T. guianensis and the investigation of the action of these extracts on the activity of gelatinases using zymography. Matrix metalloproteinases (gelatinases) have prognostic influences in human cancers, where higher expressions of these enzymes are associated with increased aggressiveness and biological behavior of tumors. Many natural products have been tested on several stages of carcinogenesis to demonstrate their effectiveness in the inhibition or activation of molecules that are important for tumor progression. This study identified the fractions obtained from the crude extract of T. guianensis (Stick pigeon), which efficiently inhibited gelatinases.

Flow rate, pH and calcium concentration of saliva of children and adolescents with type 1 diabetes mellitus

Alterations in salivary parameters may increase the caries risk in diabetic children, but, contradictory data on this issue have been reported. The aims of this study were to compare salivary parameters (flow rate, pH and calcium concentration) between healthy and type 1 diabetes mellitus (T1DM) individuals. The sample consisted of 7- to 18-year-old individuals divided into two groups: 30 subjects with T1DM (group A) and 30 healthy control subjects (group B). Fasting glucose levels were determined. Unstimulated and stimulated saliva was collected. The pH of unstimulated saliva was measured with paper strips and an electrode. Calcium concentrations in stimulated saliva were determined with a selective electrode. Group A individuals had inadequate blood glucose control (HbA1C >9%), with means ± SD unstimulated salivary flow rate of 0.15 ± 0.1 mL/min compared to 0.36 ± 0.2 mL/min for group B (P < 0.01). Stimulated salivary flow rate was similar by both groups and above 2.0 mL/min. Saliva pH was 6.0 ± 0.8 for group A and significantly different from 7.0 ± 0.6 for group B (P < 0.01). Salivary calcium was 14.7 ± 8.1 mg/L for group A and significantly higher than 9.9 ± 6.4 mg/L for group B (P < 0.01). Except for elevated calcium concentrations in saliva, salivary parameters favoring caries such as low saliva pH and unstimulated salivary flow rate were observed in T1DM individuals.

Efeitos de diferentes intervalos de recuperação no desempenho muscular isocinético em idosos / Effects of different rest intervals on isokinetic muscle performance among older adults

OBJETIVO: Comparar os efeitos de diferentes intervalos de recuperação (IR) entre séries de contração isocinética no desempenho muscular em idosos. MÉTODOS: Vinte idosos voluntários (66,9±3,9 anos, 76,1±13,4kg, 169±5,2cm) foram submetidos a três sessões de exercício resistido isocinético unilateral da musculatura extensora do joelho com diferentes IR (1 minuto, 2 minutos, e 3 minutos) na velocidade de 60°•s-1. Cada sessão consistia em três séries de 10 repetições durante as quais foram avaliados o pico de torque (PT), trabalho total (TT) e índice de fadiga (IF). ANOVA fatorial para medidas repetidas, com a análise de Post hoc por Bonferroni, foi utilizada para identificar possíveis diferenças entre os IR. O nível de significância estatístico utilizado foi de p<0,05. RESULTADOS: Não foram observadas diferenças no desempenho muscular entre as 1as séries nos diferentes IR (p>0,05). Apesar de ter sido observado menor desempenho muscular na 3ª série em todos os IR, maiores quedas no PT, TT e IF foram observadas quando adotado o IR de 1minuto (p<0,05). CONCLUSÃO: Os resultados mostraram que a variável IR exerce importante influência sobre o desempenho muscular isocinético em idosos, principalmente a partir da 3ª série, o que sugere incrementos no IR à medida que séries subsequentes forem executadas durante a mesma sessão de exercícios.

OBJECTIVE: To compare the effects of different rest intervals (RI) between sets of isokinetic contractions on muscle performance in older adults. METHODS: Twenty older participants (66.9±3.9 years; 76.1±13.4kg; 169±5.2cm) underwent three sessions of unilateral isokinetic training for the knee extensor muscles, with different RI (1 minute, 2 minutes and 3 minutes) at an angular velocity of 60°•s-1. Each session consisted of three sets of 10 repetitions, during which the peak torque (PT), total work (TW) and fatigue index (FI) were evaluated. Factorial ANOVA for repeated measurements, with Bonferroni post-hoc analysis, was used to identify possible differences between the RI. The statistical significance level was set at p<0.05. RESULTS: No differences in muscle performance during the first sets were observed between the different RI (p>0.05). Although muscle performance was lower during the third sets with all RI, the greatest decreases in PT, TW and FI occurred with the 1 minute RI (p<0.05). CONCLUSIONS: The results showed that the RI variable has an important influence on isokinetic muscle performance in older adults, particularly from the third sets onwards, which suggests that RI should be increased as successive sets are performed within the same exercise session.

Efeitos do Tai Chi Chuan na força dos músculos extensores dos joelhos e no equilíbrio em idosas / Effects of Tai Chi Chuan on knee extensor muscle strength and balance in elderly women

CONTEXTUALIZAÇÃO: Alguns estudos têm indicado que o Tai Chi Chuan (TCC) é capaz de melhorar o condicionamento físico, a força muscular e o equilíbrio entre os praticantes idosos, prevenindo quedas, fraturas e dependência física. OBJETIVO: Verificar os efeitos do TCC no equilíbrio (EQ) e na força dos músculos extensores dos joelhos (F) em mulheres idosas. MATERIAIS E MÉTODOS: Participaram do estudo 77 mulheres saudáveis, não praticantes de atividade física orientada. No Grupo Experimental (G1) foram incluídas 38 voluntárias (68 ± 5 anos) e no Grupo Controle (G2), 39 voluntárias (69 ± 7 anos). O G1 praticou o TCC estilo Yang de 24 movimentos durante 12 semanas, três vezes por semana, com duração de 50 minutos. O G2 não realizou atividades físicas orientadas. A força foi mensurada pelo teste de 1-RM na cadeira extensora e o equilíbrio foi avaliado utilizando o teste de apoio unipodal com os olhos fechados. Na análise estatística, utilizou-se teste de normalidade, split-plot análise de variância (ANOVA) e correlação de Pearson. RESULTADOS: O Grupo Experimental apresentou incrementos de 17,83 por cento na F e 26,10 por cento no EQ. O Grupo Controle não apresentou alteração significativa em nenhuma variável. Não foi observada correlação significativa entre estas duas variáveis no G1 (r= 0,09; p= 0,554) e no G2 (r= 0,07; p= 0,660). CONCLUSÕES: Estes resultados sugerem que o TCC melhora F e EQ em mulheres idosas. Entretanto, a força dos músculos extensores dos joelhos não está necessariamente ligada ao equilíbrio nesta modalidade.

BACKGROUND: Some studies have indicated that Tai Chi Chuan (TCC) is capable of improving physical fitness, muscle strength and balance in elderly people. This improvement could prevent falls, fractures and physical dependence. OBJECTIVE: To investigate the effects of TCC on balance and knee extensor muscle strength among elderly women. METHODS: Seventy-seven healthy women who were not engaged in any guided physical activity participated in this study. There were 38 volunteers (68 ± 5 years) in the Experimental Group and 39 volunteers (69 ± 7 years) in the Control Group. The Experimental Group practiced 24-movement Yang-style TCC for 12 weeks, consisting of 50-minute sessions three times per week. The Control Group did not perform any guided physical activities. Strength was measured using the one maximum repetition test in an extensor chair and balance was evaluated using the unipodal support test with the eyes closed. The statistical analysis consisted of the normality test, split-plot analysis of variance (ANOVA) and Pearson's correlation coefficient. RESULTS: The Experimental Group presented increases of 17.83 percent in knee extensor muscle strength and 26.10 percent in balance. The Control Group did not show any significant changes in these variables. No significant correlation was observed between these two variables in the Experimental (r= 0.09; p= 0.554) or in the Control Groups (r= 0.07; p= 0.660). CONCLUSIONS: These results suggest that TCC improves knee extensor muscle strength and balance among elderly women. However, knee extensor muscle strength was not necessarily linked to balance in this activity.

A multiplex single-base extension protocol for genotyping Cdx2, FokI, BsmI, ApaI, and TaqI polymorphisms of the vitamin D receptor gene

The well-described role of the vitamin D endocrine system in bone metabolism makes its receptor a widely investigated candidate gene in association studies looking for the genetic basis of complex bone-related phenotypes. Most association studies genotype five polymorphic sites along the gene using PCR-RFLP and allele-specific amplification methods, which may not be the better choice in large case/control or cross-sectional studies. In this case, genotyping SNPs in parallel and using automated allele-calling methods are important to decrease genotyping errors due to manual data handling and save sample in cases where the amount of DNA is limited. The aim of this study was to present a straightforward method based on multiplex PCR amplification followed by multiplex single-base extension as a simple way to genotype five vitamin D receptor gene polymorphisms in parallel, which may be implemented in medium- to large-scale case/control or cross-sectional studies. The results regarding method feasibility and optimization are presented by genotyping eight paternity trios and seven samples of Brazilian postmenopausal women who took part in an ongoing association study carried out by members of our group.

Atividade clastogênica e genotóxica de altas concentrações do extratoaquoso de Agaricus brasiliensis e diferentes respostas quando associadoaos inibidores de reparo de DNA, ARA-C e 3DEOT, in vitro / Clastogenic and genotoxic activity of high concentrations of Agaricus

O Agaricus brasiliensis Wasser & Didukh – Ab (=Agaricus blazei Murrill ss. Heinemann) é um basidiomiceto que vem sendo consumido em diversas partes do mundo no combate e tratamento de muitas doenças. Neste estudo, foram testados, em células de ovário de hamster chinês (CHO-k1), os efeitos clastogênicos e genotóxicos de altas concentrações de Ab e seu potencial protetor, por meio dos ensaios de aberração cromossômica (AC) e cometa (SCGE), associados a dois bloqueadores de reparodo DNA (citosina arabinoside trifosfato - Ara-C - inibidor de DNA polimerase α e 3’deoxitimidina5’trifosfato - 3DeoT - inibidor de DNA polimerase β), na presença ou não de um agente alquilante(metilmetanosulfonato). No teste de clastogenicidade, verificou-se que as concentrações 0,2 e 0,4 não se mostraram indutoras de dano, ao contrário da maior concentração (0,6). Nos tratamentos de genotoxicidade no SCGE, a concentração de 0,2 do extrato não mostrou atividade genotóxica, ao contrário das concentrações de 0,4 e 0,6, as quais foram efetivas indutoras de danos no DNA. Os resultados de anticlastogenicidade indicaram que, na maioria dos tratamentos realizados, o extrato aquoso de Ab não apresentou atividade protetora contra danos no DNA, induzidos pela Ara-C e Ara-C + MMS. Pelo SCGE, Ab, nas três concentrações testadas, não mostrou atividade antigenotóxica. Os dados sugerem cuidado no consumo e ingestão de Ab por seres humanos, principalmente em altas concentrações.