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STUDY QUESTION: What is the best source of ovarian cells for the artificial ovary: medulla or cortex, cryopreserved or fresh? SUMMARY ANSWER: Ovarian cells from fresh medullary tissue, which can be isolated in larger numbers, show higher viability and are able to improve graft vascularization. WHAT IS KNOWN ALREADY: In a previous study, addition of endothelial cells along with ovarian cells was found to be crucial for formation of a well-vascularized ovary-like structure. This study is the first to evaluate both the effect of cryopreservation and the source of ovarian tissue on isolated ovarian cells. STUDY DESIGN, SIZE, DURATION: Prospective experimental study in an academic research unit using ovarian tissue from seven patients undergoing surgery for benign gynecologic disease. participants/materials, setting, methods: Ovarian tissue was retrieved from seven patients, with one half processed as fresh (fresh group) and the other half frozen and thawed before processing (frozen group). In each group, ovarian cells from the cortex and medulla were isolated separately, and their viability was tested using a calcein AM/ethidium homodimer viability assay. Fifty thousand cells were then encapsulated in fibrin and grafted to peritoneal pockets in nude mice (14 in all). Grafts recovered after 7 days were analyzed by immunohistochemistry for the presence of ovarian cells (vimentin), proliferation (Ki67) and graft vascularization (double CD34). Cell apoptosis was analyzed by TUNEL assay. MAIN RESULTS AND THE ROLE OF CHANCE: Cryopreservation decreased ovarian cell yield (-2804 cells/mg, P = 0.015) and viability (-9.72%, P = 0.052) before grafting and had a considerable (5-fold, P = 0.2) but non-significant negative impact on ovarian cell presence in grafts. The medulla yielded many more cells (+3841 cells/mg, P < 0.001 ) with higher viability (+ 18.23%, P < 0.001 ) than did the cortex. Moreover, grafts with cells from the medulla exhibited a statistically significant 6.44- and 2.47-fold increase in human and total vascular surface area, respectively. P-values were adjusted for multiple testing using the Benjamini-Hochberg method to achieve a 10% false discovery rate and adjusted P-values, 0.1 were therefore considered significant. limitations, reasons for caution: Pilot study involving a limited number of experiments. WIDER IMPLICATIONS OF THE FINDINGS: Knowing that fresh medullary tissue is the best source of stromal cells is important for construction of the artificial ovary, as isolated follicles require structural support and a rich vascular network for their survival and development. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (5/4/150/5 and 7.45 18.12F), Fonds Spéciaux de Recherche, Fondation Saint Luc and Foundation Against Cancer, and donations from Mr Pietro Ferrero, Baron Frère and Viscount Philippe de Spoelberch. None of the authors have any conflicting interests to declare. [ABSTRACT FROM AUTHOR]

Several studies have reported the adverse effects of recalcitrant compounds and emerging contaminants present in industrial effluents, which are not degradable by ordinary biological treatment. Many of these compounds are likely to accumulate in living organisms through the lipid layer. At concentrations above the limits of biological tolerance, these compounds can be harmful to the ecosystem and may even reach humans through food chain biomagnification. In this regard, advanced oxidation processes (AOPs) represent an effective alternative for the removal of the pollutants. This study focused on the AOP involving the use of ultraviolet radiation in homogeneous and heterogeneous systems. Based on the literature review, comparisons between natural and artificial light were established, approaching photoreactors constructive and operational characteristics. We concluded that the high availability of solar power in Brazil would make the implementation of the AOP using natural solar radiation for the decontamination of effluents feasible, thereby contributing to clean production and biodiversity conservation. This will serve as an important tool for the enforcement of environmental responsibility among public and private institutions. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the degradation and mineralization of ethylenethiourea (ETU) in water by ozonation at different pH values and in the presence of hydrogen peroxide. Degradation experiments were performed using an initial ETU concentration of 50 ppm for 180 min with a gas flux of 0.25 dm min and an O production rate of 12.1 mg min. Degradation of by-products was monitored by direct injection electrospray ionization mass spectrometry (ESI-MS), ETU concentration was determined by HPLC-UV, and its mineralization was detected by total organic carbon (TOC) analysis. Optimum degradation of ETU in water was observed at pH = 11, whereas at pH = 3, the degradation of ETU was slowest, indicating that the reaction occurred through different mechanisms. The additional effects of hydroxyl radicals formed at the highest pH can be used to explain the results obtained in this study. Peroxone experiments were carried out in the presence of 400 and 800 mg L HO; the degradation of ETU was faster at 400 mg L HO. This was attributed to the scavenging effect of the excess HO. ETU treatment by ozonation produced several by-products of degradation such as ethylene urea and 2-imidazoline. [ABSTRACT FROM AUTHOR]

Healthy individuals were examined in terms of the pattern of activity of the masseter and temporal muscles in their anterior portion of both right and left sides, respectively, with the maximum bite force. The study consisted in seventeen adult volunteers with no sign of apparent temporomandibular dysfunction, of both genders, connected to the School of Dentistry of Piracicaba, with average age of 25 years old. The electromyography data were obtained, bilaterally, of the masseter, anterior portion of temporal and suprahyoid muscles in the postural and isometric positions. Were utilized surface passive electrodes for kids of Ag/AgCl, of circular format and dischargeable of Meditrace® Kendall-LTP, model Chicopee MA01, attached to a pre-amplifier with gain of 20 times forming a differential circuit. The records of the electrical signs were captured by the equipment EMG-8OOC of EMG System of Brazil Ltd. of eight channels, with frequency of 2 KHz and 16 bits of resolution, digital filter with band pass of 20 to 500Hz. It was utilized also a pressurized transductor which consists of a pressurized rubber tube connected to a sensor element (MPX 5700) to obtain the maximum bite force. The statistic tests used were linear correlation, test t in pair and analysis of variance. Probability of p<0, 05 were significant considered statistically. The results showed a certain degree of muscular asymmetry for the masseter and anterior portion of temporal muscles that depended on the task performed or contraction level. The index of asymmetry was lower in the postural position than in the maximum bite force. [ABSTRACT FROM AUTHOR]

Contents The aim of this study was to evaluate the efficiency of 1 M dimethylsulphoxide (DMSO), ethylene glycol (EG), propylene glycol (PROH) and glycerol (GLY) to cryopreserve primordial follicles. The first evaluation was performed soon after cryopreservation and the second evaluation after 4 days of in vitro culture, using the cryoprotectants that allowed the higher results (higher follicular survival rate) after cryopreservation. The results after follicular isolation (control) and cryopreservation using 1 M DMSO, EG, PROH and GLY showed that the mean number (± SEM) of live follicles per millilitre was 3204 (100%) ± 319.27, 2798 (87%) ± 239.14, 2492 (78%) ± 345.8, 448 (14%) ± 46.3 and 208 (7%) ± 75.26, respectively. Higher follicular survival was reported when DMSO and EG were used. Control follicles and follicles cryopreserved with these two cryoprotectants were cultured and the percentage of follicular survival was 55% (control), 42% (EG) and 34% (DMSO). Similar results were found between control and follicles cryopreserved with EG. In conclusion, 1 M EG is the most effective cryoprotectant to preserve primordial follicles isolated from ovaries of sheep. [ABSTRACT FROM AUTHOR]

Contents The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre-antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20°C for 6, 12 or 18 h. After storage, pre-antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20°C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4°C for 18 h and at 20°C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4°C for up to 18 h or at 20°C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro. [ABSTRACT FROM AUTHOR]

A pesquisa discute as proposições de ensino da oralidade presentes em duas coleções de livros didáticos de língua portuguesa (doravante C1 e C2) destinadas aos anos iniciais de escolarização (1ª ao 5ºanos). Visa compreender de que forma o livro didático, enquanto suporte para o ensino-aprendizagem, contribui para o trato do oral, objeto didático em busca de afirmação nas práticas cotidianos dos professores (MARCUSCHI, 2008; MARTINS; 2012). Subsidiamos a discussão teórica à luz da noção de língua como interação (BAKHTIN, 1992) e da noção de oralidade enquanto prática social interativa para fins comunicativos (MARCUSCHI, 2001; SCHNEUWLY e DOLZ, 2004). No trato metodológico, destacamos um conjunto de atividades recorrentes ao longo do projeto didático das obras, cujo objetivo anunciado encaminhava-se para ensinar a oralidade. Estruturamos a análise a partir de uma dimensão qualitativa de pesquisa (MINAYO, 1994) agrupando os dados nas categorias 1) Ensino do Gênero Oral e 2) Ensino da Relação Fala-Escrita. Os resultados demonstram que as coleções favorecem a reflexão sobre a oralidade através de gêneros textuais pertinentes ao trabalho com o referido eixo, contudo, as atividades se concentram em explorar a oralidade no espaço escolar, sem refletir sobre o seu uso em ambiente real de produção. No âmbito da relação fala-escrita, as coleções apresentam perfis diferenciados de compreensão, enquanto a C1 aborda as modalidades na dimensão do contínuo tipológico dos gêneros textuais, a C2 polariza seu olhar e assume uma perspectiva dicotômica. Essa realidade pode ser caracterizada pela incipiência do cenário teórico-metodológico na exploração do referido objeto de ensino. Palavras-chave: livros didáticos de língua portuguesa; gêneros textuais orais; ensino da oralidade; relação fala – escrita.