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From an evolutionary point of view, the gametes are the cells in the body that matter the most as they are the ones who transmit their genes to the next generation ensuring continuation of the species. Being able to generate mature oocytes in vitro is of great interest. Oocytes are the key to totipotency and are able to reprogram somatic cells in approximately one day. In addition, in contrast to a clump of pluripotent stem cells, once the developmental program has started, fertilized oocytes develop into a clump of cells with positional in formation and the possibility to differentiate into both the embryonic and the extraembryonic lineages that form a complete developing and viable organism. How to instruct pluripotent stem cells to become oocytes in vitrois still unclear and even though the first steps to obtain mouse oocytes have recently been successfully demonstrated, inducing meiosis progression and folliculogenesis in vitro are still far from being understood and have not yet been accomplished. In humans, the specific molecular niche that leads to correct oogenesis is less understood. Here, we discuss the current status of in vitro differentiation of human pluripotent stem cells into gametes, in particular to oocytes.

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From an evolutionary point of view, the gametes are the cells in the body that matter the most as they are the ones who transmit their genes to the next generation ensuring continuation of the species. Being able to generate mature oocytes in vitro is of great interest. Oocytes are the key to totipotency and are able to reprogram somatic cells in approximately one day. In addition, in contrast to a clump of pluripotent stem cells, once the developmental program has started, fertilized oocytes develop into a clump of cells with positional in formation and the possibility to differentiate into both the embryonic and the extraembryonic lineages that form a complete developing and viable organism. How to instruct pluripotent stem cells to become oocytes in vitrois still unclear and even though the first steps to obtain mouse oocytes have recently been successfully demonstrated, inducing meiosis progression and folliculogenesis in vitro are still far from being understood and have not yet been accomplished. In humans, the specific molecular niche that leads to correct oogenesis is less understood. Here, we discuss the current status of in vitro differentiation of human pluripotent stem cells into gametes, in particular to oocytes.(AU)

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The chicken (Gallus gallus) embryo has been used as a classic model system for developmental studies because of its easy accessibility for surgical manipulation during embryonic development. Sex determination in birds is chromosomally based (ZZ for males and ZW for females); however, the basic mechanism of sex determination is still unknown. Here, the dynamics of expression of candidate genes implicated in vertebrate sex determination and differentiation were studied during embryonic chicken gonadal development. Gene expression profiles were obtained before, during, and after gonadal sex differentiation in females and males for DMRT1, SOX3, SOX9, DAX1, SCII, HINTZ, HINTW, and the male hypermethylated (MHM) region. Transcripts for the HINTZ, DMRT1, DAX1, SCII, and SOX9 genes were observed in both sexes, but expression was higher in male gonads and may be correlated with testicular differentiation. The expression patterns of HINTW, SOX3, and MHM suggest that they may act in ovary development and may be involved in meiosis entry. MHM was upregulated and DMRT1 was downregulated in females at the same developmental stage. This may indicate a regulation of DMRT1 by MHM ncRNA. Similar dynamics were observed between HINTW and HINTZ. This study reports on the MHM expression profile during gonadal development and its correlation with the expression of genes involved in vertebrate sex determination.

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This contribution describes and illustrates the male genitalia of two new species of Ectobiidae belonging to Pseudophyllodromiinae, Chorisoneura Brunner von Wattenwyl, and Blattellinae, Xestoblatta Hebard. Both species were collected in the Santa Lúcia Biological Reserve in the state of Espírito Santo, Brazil.

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Neoblattella mista sp. nov. is described and illustrated based on male genitalia and morphological characters of a single specimen collected in the town of Coari, State of Amazonas, Brazil. By studying the literature on the genus, we determined that N. mista sp. nov. differs from the other four known complexes in the morphology of its genital structures, including the supra-anal plate, subgenital plate, right and left phallomeres, median genital sclerite and tergal modification in the abdomen, and is placed in the new "mista complex".

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Objetivo: Avaliar a influência da frequência estimulatória envolvida na analgesia induzida por eletroacupuntura em cervicalgia. Métodos: Comparou-se o desempenho da analgesia produzida em 2Hz, 100Hz, 1000Hz, 2500Hz e um grupo só com acupuntura, sem estímulo elétrico, avaliado por meio de algometria de pressão, Escala Visual Analógica (EVA) e frequência cardíaca. Utilizou-se um estimulador elétrico microprocessado, com forma de pulso em padrão pulsado, monofásico, retangular, balanceado assimétrico, comfase secundária em exponencial decrescente, com período de estimulação de 4 segundos e repouso de 3 segundos. A amostra contou com 66 voluntários com cervicalgia tensional, idade média de 33,67±9,97 anos, 89,5% do gênero feminino e 10,5% do masculino. Resultados: Não houve diferenças entre os grupos para as variáveis nota atribuída à dor pela EVA e frequência cardíaca, sendo que em todos os grupos houve melhoras analgésicas. No entanto, quando comparado o comportamento antes-depois, por meio da algometria de pressão, para um mesmo indivíduo, dentro de seu próprio grupo, houve vantagens analgésicas para o uso de 2500Hz (p=0,006 para a base da região occiptal; p=0,003 para o trapézio direito; e p=0,013 para o trapézio esquerdo), seguido de 100Hz(p=0,035, p=0,016 e p=0,038, para as mesmas regiões, respectivamente). Conclusão: Recomenda-se preferencialmente a aplicação de 2500Hz e 100Hz em eletroacupuntura para analgesia em cervicalgia tensional.

Objective: To assess the influence of the stimulating frequency involved in analgesia induced by electroacupuncture for neck pain. Methods: The performance of the analgesia produced by 2Hz, 100Hz, 1000Hz and 2500Hz was compared with a group withacupuncture alone (without electrical stimulation), by means of pressure algometry, a visual analog scale (VAS) and heart rate. We used an electrical stimulator with a microprocessor yielding standard, single-phase, rectangular and asymmetrical balanced pulsed waveforms with a secondary phase decreasing exponentially. Stimulation periods were 4s, and resting periods were 3s. The sample included 66 volunteers with neck pain due to muscular tension, mean age 33.67±9.97 years, 89.5% female and 10.5% male. Results: There were no differences between the groups regarding the variables of degree of pain (according to the VAS) and heart rate, and all groups presented analgesic improvement. However, when comparing pressure algometry findings for the same individual before and after the treatment, within the same group, we found analgesic advantages in using 2500Hz (p=0.006 for the base of the occipital region, p=0.003 for the right trapezius and p=0.013 for the left trapezius), followed by 100Hz (p=0.035, p=0.016 and p=0.038 for thesame regions, respectively). Conclusion: We preferentially recommend 2500Hz and 100Hz applications of electroacupuncture for analgesia of neck pain due to muscular tension.

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The nutritive value of manioc flour (Manihot esculenta) enriched with yeast protein (Saccharomyces cerevisiae) added to a food mixture most frequently consumed by low-income populations was assessed in female Wistar rats (n = 30; 100-120 days old). Animals were divided into three groups, mated and had free access to diets and water. Diets were as follows: beans, rice, yeast-enriched manioc flour (BRYMF17); beans, rice, manioc flour (BRMF13); casein (17% protein) (CAS17). Body weight gains and food consumption were recorded during pregnancy and lactation. At the parturition, the number of pups per litter was recorded and offspring were uniformly distributed (7 pups per litter). Weight gains were determined until weaning (21 days). At weaning two youngs were selected from each litter and individually housed. Weight gains, food consumption and the length of the tail were measured until rats were 70 days old. Rats had their liver and brain removed for protein determination and wet and relative weights. Liver samples were histologically examined. Blood hemoglobin, hematocrit and proteins, as well as the Food Efficiency Ratio (FER), were determined. ANOVA and Tukey's test were used. The experimental diet had not significant effect on pregnant and lactating dams. Values for the investigated parameters were higher in experimental youngs than in their controls and lower than in the standard group. This yeast protein-enriched manioc flour proved to be valid in terms of dietary supplementation.

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A Multimistura (MM)--sweet cassava (Manihot esculenta Crantz) leaf flour, wheat bran (Tritium aestivum L.), egg shell powder, pumpkin (Cucurbita Spp) and sunflower (Heliantus annus) seed flours--was added to a mixture of Beans, 7% (Phaseolus vulgaris) and Rice, 3% (Oryza sativa) and its effects, were assessed in weanling, male albino (Wistar) rats (n = 60). Animals were divided into 6 groups: groups 1, 2 and 3 were fed beans + rice + multimixture (B + R + MM), beans + rice (B + R) and 10% Casein, respectively; the remaining groups were maintained on a protein-free diet (PFD) for 14 d and then submitted to the same feeding protocol. Microbiological assays were performed in all MM samples. The Coefficient of Digestablity (CD), the Food Efficiency Ratio (FER), Protein Efficiency Ratio (PER), Net Protein Utilization (NPR), serum hemoglobin (Hb) and hematocrit (Ht), carcass total lipids were determined. Rats had their liver, brain, gonads, testes, spleen and left kidney removed for wet dry weights. Liver samples were histologically examined. The Mann-Whitney test was used. The protein content of B + R diet increased slightly after MM addition (0.23 g/100 g). Three out of four MM samples had moulds and yeasts. CD values were 90% and 70% for casein and B + R + MM-fed rats, respectively. The highest values for FER, PER and NPR were seen in the casein-fed rats without protein depletion. The casein-fed group had heavier organs (wet and dry weights) and higher values for carcass fat and serum Hb and Ht. Steatosis was present in both groups, with or without protein depletion. Short or long-term MM consumption, at least under our experimental conditions, had no significant effects on investigated parameters.

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Um estudo em 20 casos utilizando a tecnica de Sarmiento e col. foi realizado, com pequena variacao de tecnica. Os resultados determinam que quando utilizamos a posicao supinada os resultados sao superiores

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