Cholesterol and ergosterol affect the activity of Staphylococcus aureus antibiotic efflux pumps.

The aim of this study is to evaluate the effect of ergosterol on steroids and cholesterol efflux pumps in multidrug resistant strains of S. aureus. Were used RN4220 harboring plasmid pUL5054, which carries the gene encoding the MsrA macrolide efflux protein; and IS-58, which possesses the TetK tetracycline efflux protein; 1199B resists hydrophilic fluoroquinolones via a NorA-mediated mechanism and wild strain 1199B. The Minimal Inhibitory Concentration (MIC) was determined and the evaluation of possible inhibition of efflux pumps by reduction of MIC. Some of the detrimental effects on bacterial cells can be attributed to the detergent properties of cholesterol and ergosterol on account of their amphipathic structure. Besides the cholesterol did not affect directly the pump structure, a synergism was observed, maybe due the interaction with the cell membrane and interference in the lipid bilayer.

The effect of thermal treatment of whole soybean flour on the conversion of isoflavones and inactivation of trypsin inhibitors.

The aim of this paper was to evaluate the effect of the thermal treatment of whole soybean flour (WSF) on the conversion of isoflavones and the inactivation of trypsin inhibitors. Soybeans were ground and whole soybean flour was obtained and subjected to heat treatment in an oven for 10, 15 and 20min at 100, 150 and 200°C according to a 3(2) experimental design. The response functions were taken to be the contents of different isoflavone forms and the residual activity of trypsin inhibitors. The thermal treatment in the oven altered the content and profile of the different isoflavones forms. At 200°C for 20min, there was a higher conversion of malonylglycosides to acetylglycosides, ß-glycosides and aglycones and a significant reduction in the activity of trypsin inhibitors. Mathematical models were established to estimate the process parameters in obtaining the WSF with isoflavone conversions and reductions in trypsin inhibitor activity.

Viability of in vitro produced embryos of gyr cattle (Bos indicus) after cryopreservation by vitrification under field conditions / Viabilidade de embriões gir (Bos indicus) produzidos in vitro após criopreservação em condições de campo pela vitrificação

The aim of this study was to evaluate the pregnancy rate of in vitro produced embryos of Gyr cattle (Bos indicus) after cryopreservation by the vitrification method under field conditions. Blastocysts in different developmental stages were transferred to recipient cows either fresh (n = 140) or warmed after vitrification (n = 138). The pregnancy rates obtained for fresh embryos were 46.15% (initial blastocyst), 46.93% (blastocyst) and 50.0% (expanded blastocyst) at 35 days post-fertilization, and 43.58% (initial blastocyst), 46.93% (blastocyst) and 50.0% (expanded blastocyst) at 60 days. The pregnancy rates after embryo vitrification were 35.0% (initial blastocyst), 42.30% (blastocyst) and 43.47% (expanded blastocyst) at 35 days post-fertilization, and 32.50% (initial blastocyst), 38.46% (blastocyst) and 43.47% (expanded blastocyst) at 60 days. Embryo vitrification or blastocyst developmental stage did not affect pregnancy rates or incidence of embryonic death. In conclusion, vitrification of Gyr (Bos indicus) embryos under field conditions is an efficient method that can be implemented to use surplus in vitro produced embryos without affecting pregnancy rates...

Objetivou-se com o trabalho avaliar a taxa de prenhez a partir de embriões de bovinos da raça Gir (Bos indicus) produzidos in vitro após criopreservação em condições de campo pelo método de vitrificação. Blastocistos em diferentes estádios de desenvolvimento foram transferidos a fresco (n = 140) ou aquecidos após a vitrificação (n = 138). As taxas de prenhez de embriões frescos foram 46,15% (blastocisto inicial), 46,93% (blastocisto) e 50,00% (blastocisto expandido) aos 35 dias e 43,58% (blastocisto inicial), 46,93% (blastocisto) e 50,00% (blastocisto expandido) aos 60 dias pós-fertilização, respectivamente. As taxas de prenhez após a vitrificação foram 35,00% (blastocisto inicial), 42,30% (blastocisto) e 43,47% (blastocisto expandido) aos 35 dias e 32,50% (blastocisto inicial), 38,46% (blastocisto) e 43,47% (blastocisto expandido) aos 60 dias pós-fertilização, respectivamente. A vitrificação do embrião ou estádio do desenvolvimento não afetaram as taxas de prenhez ou incidência de morte embrionária. Em conclusão, a vitrificação de embriões de bovinos da raça Gir (Bos indicus) sob condições de campo é um método eficiente que pode ser implementado para aproveitar os embriões produzidos in vitro excedentes sem afetar a taxa de prenhez...

Viability of in vitro produced embryos of gyr cattle (Bos indicus) after cryopreservation by vitrification under field conditions / Viabilidade de embriões gir (Bos indicus) produzidos in vitro após criopreservação em condições de campo pela vitrificação

The aim of this study was to evaluate the pregnancy rate of in vitro produced embryos of Gyr cattle (Bos indicus) after cryopreservation by the vitrification method under field conditions. Blastocysts in different developmental stages were transferred to recipient cows either fresh (n = 140) or warmed after vitrification (n = 138). The pregnancy rates obtained for fresh embryos were 46.15% (initial blastocyst), 46.93% (blastocyst) and 50.0% (expanded blastocyst) at 35 days post-fertilization, and 43.58% (initial blastocyst), 46.93% (blastocyst) and 50.0% (expanded blastocyst) at 60 days. The pregnancy rates after embryo vitrification were 35.0% (initial blastocyst), 42.30% (blastocyst) and 43.47% (expanded blastocyst) at 35 days post-fertilization, and 32.50% (initial blastocyst), 38.46% (blastocyst) and 43.47% (expanded blastocyst) at 60 days. Embryo vitrification or blastocyst developmental stage did not affect pregnancy rates or incidence of embryonic death. In conclusion, vitrification of Gyr (Bos indicus) embryos under field conditions is an efficient method that can be implemented to use surplus in vitro produced embryos without affecting pregnancy rates...(AU)

Objetivou-se com o trabalho avaliar a taxa de prenhez a partir de embriões de bovinos da raça Gir (Bos indicus) produzidos in vitro após criopreservação em condições de campo pelo método de vitrificação. Blastocistos em diferentes estádios de desenvolvimento foram transferidos a fresco (n = 140) ou aquecidos após a vitrificação (n = 138). As taxas de prenhez de embriões frescos foram 46,15% (blastocisto inicial), 46,93% (blastocisto) e 50,00% (blastocisto expandido) aos 35 dias e 43,58% (blastocisto inicial), 46,93% (blastocisto) e 50,00% (blastocisto expandido) aos 60 dias pós-fertilização, respectivamente. As taxas de prenhez após a vitrificação foram 35,00% (blastocisto inicial), 42,30% (blastocisto) e 43,47% (blastocisto expandido) aos 35 dias e 32,50% (blastocisto inicial), 38,46% (blastocisto) e 43,47% (blastocisto expandido) aos 60 dias pós-fertilização, respectivamente. A vitrificação do embrião ou estádio do desenvolvimento não afetaram as taxas de prenhez ou incidência de morte embrionária. Em conclusão, a vitrificação de embriões de bovinos da raça Gir (Bos indicus) sob condições de campo é um método eficiente que pode ser implementado para aproveitar os embriões produzidos in vitro excedentes sem afetar a taxa de prenhez...(AU)

Análise fitoquímica e atividade antifúngica do óleo essencial de folhas de Lippia sidoides Cham. e do Timol contra cepas de Candida spp / Phytochemical analysis and antifungal activity of the essential oil of Lippia sidoides Cham. and of the Thymol against Candida strains

RESUMO A resistência de fungos do gênero Candida aos fármacos químicos tem lançado o desafio de se identificar novas substâncias que possuam atividade antibiótica ou venham a modular o efeito de produtos atualmente usados contra candidíase. O presente estudo avaliou a atividade antifúngica do óleo essencial de Lippia sidoides Cham. e do timol, sobre cepas de Candida. Inicialmente os produtos foram testados frente a 16 cepas fúngicas pela técnica de difusão em meio sólido, o que permitiu selecionar linhagens para continuidade da pesquisa. Com as linhagens de Candida krusei (CK LMBM 01, CK LMBM 02), Candida albicans (CA LM 62) e Candida tropicalis (CT LM 20), procedeu-se, por microdiluição em caldo, a determinação da Concentração Inibitória Mínima (CIM) e em meio sólido, a Concentração Fungicida Mínima (CFM) dos produtos foi identificada. O microcultivo das leveduras em meio empobrecido foi realizado para verificação de alterações morfológicas e, além disso, uma análise da composição química do óleo foi realizada por Cromatografia Gasosa acoplada à espectrometria de massas (CG-EM). Nesta análise, o constituinte majoritário foi o timol (84,95%), seguido de compostos como p-cimeno e Éter metil carvacrol, entre outros. A CIM do óleo essencial de Lippia sidoides Cham. frente às cepas variou entre 64 e 256 μg/mL, enquanto a CIM do timol foi estabelecida entre 32 e 64 μg/mL. A CFM do óleo essencial foi determinada entre 128 e 512 μg/mL e para o timol foram encontrados valores entre 64 e 128 μg/mL. Em relação à análise micromorfológica, verificada nas concentrações de CIM e CIM x 2, o óleo essencial inibiu o dimorfismo das cepas CK 01 e CT 20 na CIM e quando foi ensaiado o timol, este, na CIM, impediu a transição morfológica das cepas CK 01 e CA 62. Uma redução da morfogênese também foi obsevada na cepa CT 20, porém apenas em CIM x 2 e de forma mais discreta. Os resultados enaltecem o potencial antifúngico de L. sidoides e de seu composto majoritário timol tanto no combate à Candida quanto na neutralização de um dos fatores de virulência, a capacidade invasiva por formação de hifas e pseudohifas verificado na condição patogênica da candidíase. Estes dados são promissores e poderão incentivar futuras pesquisas sobre os aspectos fitoquímicos, toxicológicos e farmacológicos tanto do óleo essencial de Lippia sidoides como também de seus componentes químicos.

ABSTRACT The resistance of the Candida against drugs has been a challenge to the discovery of new substances with antimicrobial or modulatory effects that could be used against the cadidiasis. This work evaluated the antifungal activity of the essential oil of Lippia sidoides Cham. and of the Thymol against Candida strains. The products were tested towards 16 strains of Candida using the diffusion method, which allowed to select the strains in order to proceed with the research. The strains of Candida krusei (CK LMBM 01, CK LMBM 02), Candida albicans (CA LM 62) and Candida tropicalis (CT LM 20) were assayed by the microdilution method so that the Minimal Inhibitory Concentration (MIC) and the Minimal Fungicide Concentration (MFC) could be determined. The morphogenesis of the Candida was evaluated using poor environment in order to observe morphological changes. The composition of the essential oil was determined by GC-MS. The main compound observed was the thymol (84.95%). The MIC of the essential oil of L. sidoides and Thymol ranged between 64 to 256 μg/mL, and between 32 to 64 μg/mL respectively. The MFC of the essential oil and the thymol varied between 128 to 512 μg/mL and 64 to 128 μg/mL respectively. The morphogenesis of different Candida strains was inhibited in the MIC and MICx2 to the essential oil and thymol. The results indicated the antifungal potential of the L. sidoides and of the Thymol due to the inhibition of the invasive capacity, one of the most important virulence factors for the candidiasis` development. These results are promising to new researches about the phytochemical, toxicological and pharmacological aspects of the essential oil of L. sidoides and its phytochemical compounds.

Phenolic compounds and interaction between aminoglycosides and natural products of Lygodium venustum SW against multiresistant bacteria.

BACKGROUND: The aim of this work was to evaluate the interactions between aminoglycosides and the ethyl-acetate fraction of the fern Lygodium venustum SW (EAFLV) METHODS: The ethyl-acetate fraction was obtained from the ethanol extract of L. venustum and was assayed via the checkerboard method associated with aminoglycosides against two bacterial strains multiresistant to antibiotics. RESULTS: The antibiotic activity of all drugs, when associated with the ethyl-acetate fraction, was enhanced in an additive manner, except for the association between EAFLV and amikacin, which showed a synergistic interaction against the Escherichia coli strain. CONCLUSIONS: The results indicated that L. venustum can be a source of secondary metabolites to be used in association with antibiotics like aminoglycosides in antibiotic chemotherapy against resistant bacteria.

Structural analysis of zeolite NaA synthesized by a cost-effective hydrothermal method using kaolin and its use as water softener.

Zeolite 4A (LTA) has been successfully synthesized by a hydrothermal method, where kaolin was used as silica and alumina source. The synthesized zeolite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser granulometry, and FTIR spectroscopy. XRD data from the Rietveld refinement method confirmed only one crystallographic phase. Zeolite A morphology was observed by SEM analysis, and it showed well-defined crystals with slightly different sizes but with the same cubic shape. Particle size distribution of the crystals was confirmed by laser granulometry, whereas FTIR spectroscopy revealed significant structural differences between the starting material and the final zeolite product used as water softener.

Viabilidade in vitro de células espermáticas ovinas submetidas a diferentes diluentes e a refrigeração / In vitro viability of ovine sperm cells submitted to different diluents and refrigeration

Avaliou-se a viabilidade in vitro de células espermáticas após a adição de três diluentes comerciais, que foram comparados com o diluente tradicional Tris-gema, utilizados no processo de refrigeração do sêmen ovino, em até 48h de armazenamento. Foram utilizados nove ejaculados diários, obtidos de três reprodutores Dorper, com vagina artificial, em três repetições com intervalo de três dias. O sêmen foi mantido a 30ºC, e foram avaliadas suas características macro e microscópicas. Após formação do pool, repetiram-se as avaliações acrescidas da concentração espermática e da integridade do DNA e do acrossoma. Dividiu-se o pool em cinco tratamento, cada um constituído de uma parte de sêmen para três partes dos respectivos diluentes: Equimix (DI), Laiciphos Green Ovine (DII), FR 4 (DIII), Equimix-Gema- Equimix com gema de ovo (DIV) e Tris-Gema (DV). O material obtido em cada tratamento foi subdividido em quadruplicata, refrigerado e mantido a 4ºC até as avaliações da motilidade individual progressiva (MIP), do vigor e da integridade do DNA e do acrossoma, correspondendo a zero, 12, 24, 36 e 48h. Nas avaliações do sêmen, com o DI ocorreu a maior queda de MIP às 12h em relação aos demais grupos (P<0,05). Às 24h, os tratamentos DII, DIV e DV apresentaram a melhor MIP (P<0,05), que não divergiram (P>0,05) entre si; às 48h, o DII e o DV foram melhores (P<0,05) que os demais. Com relação ao vigor, os tratamentos DII e DV apresentaram valores mais elevados (P<0,05) em relação ao DI e DIII, a partir das 12h, e ao DIV, a partir das 24h (P<0,05). Concluiu-se que o diluente Laiciphos Green Ovine, da mesma forma que o Tris-gema, pode ser utilizado na conservação do sêmen a 4ºC por 48h, enquanto o Equimix, acrescido de 20 por cento de gema de ovo, pode ser seja utilizado no armazenamento do sêmen (4ºC) por até 24h.(AU)

The in vitro viability of sperm cells following the addition of three commercial diluents was evaluated and compared with the traditional Tris-yolk diluent for the refrigeration of ovine sperm up to 48h of storage. Nine daily ejaculates were obtained from three Dorper breeders using an artificial vagina; three repetitions were performed in a three-day interval. The semen was kept at 30ºC and macro and microscopic characteristics were evaluated. The samples were pooled and the evaluations were repeated, along with assessments of sperm concentration, DNA integrity, and acrosome integrity. The pool was distributed into five treatments, each with one part of semen to three parts of the following diluents: Equimix (DI), Laiciphos Green Ovine (DII), FR 4 (DIII), Equimix-Yolk-Equimix with egg yolk (DIV), and Tris-Yolk (DV). The material of each treatment was aliquoted in quadruplicate, refrigerated, and maintained at 4ºC until the evaluations of the individual progressive motility (IPM), vigor, DNA integrity, and acrosome integrity, corresponding to 0, 12, 24, 36, and 48h. The highest decrease of IPM occurred with DI (at 12h) in comparison to the other diluent groups (P<0.05). At 24h, DII, DIV and DV had the best IPM (P<0.05) and did not diverge from one another (P>0.05). At 48h, DII and DV had the highest values (P<0.05). Regarding vigor, DII and DV had higher values (P<0.05) than DI and DIII at 12h and higher values than DIV at 24h (P<0.05). From the results, like Tris-Yolk, and Laiciphos Green Ovine can be used for the conservation of semen at 4ºC for 48h, whereas Equimix plus 20 percent egg yolk may be used for the storage of semen at 4ºC for up to 24h.(AU)

Viabilidade in vitro de células espermáticas ovinas submetidas a diferentes diluentes e a refrigeração / In vitro viability of ovine sperm cells submitted to different diluents and refrigeration

Avaliou-se a viabilidade in vitro de células espermáticas após a adição de três diluentes comerciais, que foram comparados com o diluente tradicional Tris-gema, utilizados no processo de refrigeração do sêmen ovino, em até 48h de armazenamento. Foram utilizados nove ejaculados diários, obtidos de três reprodutores Dorper, com vagina artificial, em três repetições com intervalo de três dias. O sêmen foi mantido a 30ºC, e foram avaliadas suas características macro e microscópicas. Após formação do pool, repetiram-se as avaliações acrescidas da concentração espermática e da integridade do DNA e do acrossoma. Dividiu-se o pool em cinco tratamento, cada um constituído de uma parte de sêmen para três partes dos respectivos diluentes: Equimix (DI), Laiciphos Green Ovine (DII), FR 4 (DIII), Equimix-Gema- Equimix com gema de ovo (DIV) e Tris-Gema (DV). O material obtido em cada tratamento foi subdividido em quadruplicata, refrigerado e mantido a 4ºC até as avaliações da motilidade individual progressiva (MIP), do vigor e da integridade do DNA e do acrossoma, correspondendo a zero, 12, 24, 36 e 48h. Nas avaliações do sêmen, com o DI ocorreu a maior queda de MIP às 12h em relação aos demais grupos (P<0,05). Às 24h, os tratamentos DII, DIV e DV apresentaram a melhor MIP (P<0,05), que não divergiram (P>0,05) entre si; às 48h, o DII e o DV foram melhores (P<0,05) que os demais. Com relação ao vigor, os tratamentos DII e DV apresentaram valores mais elevados (P<0,05) em relação ao DI e DIII, a partir das 12h, e ao DIV, a partir das 24h (P<0,05). Concluiu-se que o diluente Laiciphos Green Ovine, da mesma forma que o Tris-gema, pode ser utilizado na conservação do sêmen a 4ºC por 48h, enquanto o Equimix, acrescido de 20 por cento de gema de ovo, pode ser seja utilizado no armazenamento do sêmen (4ºC) por até 24h.

The in vitro viability of sperm cells following the addition of three commercial diluents was evaluated and compared with the traditional Tris-yolk diluent for the refrigeration of ovine sperm up to 48h of storage. Nine daily ejaculates were obtained from three Dorper breeders using an artificial vagina; three repetitions were performed in a three-day interval. The semen was kept at 30ºC and macro and microscopic characteristics were evaluated. The samples were pooled and the evaluations were repeated, along with assessments of sperm concentration, DNA integrity, and acrosome integrity. The pool was distributed into five treatments, each with one part of semen to three parts of the following diluents: Equimix (DI), Laiciphos Green Ovine (DII), FR 4 (DIII), Equimix-Yolk-Equimix with egg yolk (DIV), and Tris-Yolk (DV). The material of each treatment was aliquoted in quadruplicate, refrigerated, and maintained at 4ºC until the evaluations of the individual progressive motility (IPM), vigor, DNA integrity, and acrosome integrity, corresponding to 0, 12, 24, 36, and 48h. The highest decrease of IPM occurred with DI (at 12h) in comparison to the other diluent groups (P<0.05). At 24h, DII, DIV and DV had the best IPM (P<0.05) and did not diverge from one another (P>0.05). At 48h, DII and DV had the highest values (P<0.05). Regarding vigor, DII and DV had higher values (P<0.05) than DI and DIII at 12h and higher values than DIV at 24h (P<0.05). From the results, like Tris-Yolk, and Laiciphos Green Ovine can be used for the conservation of semen at 4ºC for 48h, whereas Equimix plus 20 percent egg yolk may be used for the storage of semen at 4ºC for up to 24h.

Relationship between surgical trauma and albumin concentration in the postoperative period of digestive system operations.

AIM: Surgical trauma can provoke systemic alterations including changes in hepatic protein synthesis. Thus, it is important to point out the influence of this phenomenon on serum albumin concentration. The objective of the present work was to assess the effect of surgical trauma on serum albumin concentration during the immediate postoperative period in gastrointestinal procedures. METHODS: The study was conducted on 150 randomized adult patients submitted to elective major surgeries (Group 1) and to medium size surgeries (Group 2) of the gastrointestinal system, identified according to sex, age and skin color. Blood samples for the determination of serum albumin concentration were obtained on the day preceding and following the surgical procedure. RESULTS: There was a reduction in serum albumin both in Group 1 (P < 0.0001) and Group 2 (P < 0.0001), with no difference between sexes or patient skin colors for major surgeries. However, women showed a lower reduction in serum albumin than men in medium-sized surgeries. Also, the reduction of albumin was lower in black-skinned patients than in colored and lower in the latter than in white-skinned patients. With respect to age range, a greater reduction of albumin was observed in both groups among patients over 65 years, followed by younger patients (< 45 years) and by patients aged 45 to 65 years. CONCLUSION: Medium-sized and majors operations provoked an acute reduction in albuminemia, which was less intense among women, among the patients aged 45 to 65 years and among dark-skinned patients.

The effect of surgical procedures on serum albumin concentration.

PURPOSE: To assess the effect of surgical trauma on serum albumin concentration during the immediate postoperative period. METHODS: 200 consecutive adult patients submitted to elective major surgeries (Group 1) and to medium size surgeries (Group 2) were identified according to gender, age and skin color. Blood samples for the determination of serum albumin concentration were obtained on the day preceding and the one following the surgical procedure. Pre- and postoperative albumin data were compared by the paired t test. The gender was compared by the Student t test. The skin color and the age were compared by the repeated measured one-way ANOVA and the Tukey-Kramer tests. The level of significance was set at P < 0.05. RESULTS: There was a reduction in serum albumin in Group 1 (p < 0.0001) and Group 2 (p < 0.0001), with no difference between gender or skin colors for major surgeries. However, women showed a lower reduction than men in serum albumin in medium-sized surgeries. In medium-sized surgeries, black patients had the lowest reduction in albuminemia. The greater reduction in albuminemia occurred in patients older than 65 years old. CONCLUSION: Medium-sized and majors operations provoked an acute reduction in albuminemia, which was more intense in aged white men.

AVALIAÇÃO IMUNO-HISTOQUÍMICA DO GENE P53 NAS NEOPLASIAS MAMÁRIAS CANINAS.

O estudo dos tumores mamários em cadelas revela-se como um excelente modelo para a investigação clínicopatológica,diagnóstica e prognóstica de neoplasias mamárias que acometem a espécie humana. A Síndrome de Li Fraumenié descrita como uma condição hereditária responsável pela mutação do gene p53 levando indivíduos jovens aodesenvolvimento do câncer. A expressão do gene supressor de tumor p53 em cortes histológicos tem demonstrado valorprognóstico para tumores mamários caninos e se relaciona com malignidade e baixa taxa de sobrevivência. O presentetrabalho pesquisou a expressão celular do gene p53 na determinação do prognóstico para o paciente com câncer e sua associação com fatores prognósticos relacionados à evolução clínica do paciente. Foram analisados 73 tumores e aexpressão do anticorpo policlonal P53 foi classificada pelo sistema de cruzes, tendo sido considerada alta (acima de 50%das células marcadas) em tumores malignos. Pela Regressão Logística Nominal não houve correlação estatística de suaexpressão com morte por neoplasia, pequeno tempo de sobrevida e tempo livre da doença. Entretanto, sua expressãomostrou associação com a idade jovem das cadelas acometidas, evidenciando o seu acúmulo na célula e deixando a fêmea susceptível ao crescimento neoplásico, numa idade onde existiria, em tese, a proteção por este gene. Esta síndrome foi descrita na literatura para a espécie

The use of steroid hormones in superovulation of Nelore donors at different stages of estrous cycle.

The objective of the present study was to evaluate the superovulatory response and ova/embryo recovery from Nelore donors following treatment with a controlled internal drug releasing device and estradiol benzoate (CIDR-B program) at different stages of the estrous cycle. The control group (TI; n=40) received a standard superovulation protocol with females of this group being between days 9 and 12 of the estrous cycle (estrus = day 0). The donors that received a CIDR-B program containing 1.9 g progesterone and an intramuscular injection of estradiol benzoate (2 mg) were at day 0 (TII; n=30), between days 2 and 6 (TIII; n=30), days 7 and 12 (TIV; n=30), days 13 and 16 (TV; n=30) and days 17 and 20 (TVI; n=30) of the estrous cycle. Superovulation was induced with 400 IU of p-FSH, divided into eight decreasing doses (80/80; 60/60; 40/40; 20/20) at intervals of 12h. The donors received PGF2alpha (Cloprostenol) 48 h after beginning the treatment and CIDRs were removed 12h later. Artificial inseminations (AI) were performed 12 and 22 h after the initiation of estrus and embryos were collected 7 days after AI. The mean numbers (+/-S.E.M.) of total ova and embryos, viable (transferable) and degenerated embryos were 14.2+/-11.3, 7.4+/-6.9 and 3.2+/-3.5 (TI), 13.3+/-10.4, 7.1+/-6.2 and 3.3+/-4.3 (TII), 13.5+/-7.0, 8.1+/-6.7 and 2.3+/-3.0 (TIII), 17.4+/-9.9, 9.4+/-6.9 and 4.0+/-4.4 (TIV), 16.9+/-8.8, 9.8+/-8.1 and 2.7+/-2.5 (TV) and 13.0+/-7.8, 7.2+/-6.9 and 2.3+/-2.5 (TVI), with no significant differences (P>/=0.05) among groups. Pregnancy rates of 67.1% (TI; n=86/128), 60.8% (TII; n=59/97), 62.5% (TIII; n=73/115), 64.1% (TIV; n=84/131), 72.3% (TV; n=81/112) and 60.6% (TVI; n=63/104) were obtained with embryos transferred from these collections and did not differ significantly (P>/=0.05) among groups. The results of the present study allow us to conclude that a combination of steroid hormones may be used prior to superovulation in Nelore donors, at any stage of the estrous cycle without affecting the efficiency of embryo transfer programs.

Behavior of dense and porous hydroxyapatite implants and tissue response in rat femoral defects.

Porous and dense hydroxyapatite cylinders (PHA and DHA) were implanted into cavities produced in rat femora and the sites of implantation were examined at different times over a period of 24 weeks by microradiologic and histological techniques. Microradiographs showed the presence of a layer of trabecular bone around the implants, which became more radiopaque and thinner along the experimental time. The microradiologic methodology used was suitable for the evaluation of the interface between hydroxyapatite and newly formed bone in nondecalcified materials. Microscopic observations showed that young bone grew over the surface of both types of implants after 1 and 2 weeks of surgery and that bone also grew inside PHA implants. Progressive bone absorption was observed in both types of implants after the fourth week. A layer of fibrous tissue was formed in the interface between new bone and DHA. Mature bone with haversian systems surrounded DHA implants and filled the pores of PHA implants throughout the experimental period. The pores of PHA implants were smaller than those commonly reported, which should have been a disadvantage, although it was observed that the extra cellular fluid induced disintegration of the ceramic granules, allowing the gradual growth of bone tissue into the spaces among them, without the interposition of fibrous tissue.

Use of steroid hormone treatments prior to superovulation in Nelore donors.

The objective of this study was to evaluate the effectiveness of synchronization of follicular wave emergence using steroid hormone treatments in Nelore cows. Donors were placed into three groups. Those that were between days 9 and 12 of their cycle (estrus=day 0) formed the TI group (n=60), whilst those that were in any other stages of their estrus cycle constituted groups TII (n=60) and TIII (n=60). TI donors were submitted to a standard protocol of superovulation, however, TII and TIII donors were treated with the Syncro-Mate-B (SMB) or Controlled Internal Drug Releasing Device (CIDR-B) programs, respectively. Superovulation was induced with p-FSH, divided into eight decreasing doses at intervals of 12h. The donors received cloprostenol 48h after the beginning of the treatment and progestagens were removed 12h later. Artificial inseminations (AI) were done at 12 and 22h after the initiation of estrus and the embryo collections were done 7 days after AI. In the donors which displayed behavioral estrus, mean (+/-S.E.M.) total ova and viable (transferable) embryos were 15.8+/-1.4 and 8.3+/-1.0 (TI, n=56); 15.6+/-1.3 and 8.9+/-1.0 (TII, n=56); 17.3+/-1.0 and 9.9+/-0.9 (TIII, n=57), respectively, with no significant difference (P > or =0.05) among groups. In those animals that did not displayed behavioral estrus, the mean values of total ova and viable embryos were 3.5+/-1.6 and 0.7+/-0.5 (TI, n=4); 11.5+/-3.9 and 9.0+/-4.4 (TII, n=4); 8.7+/-5.0 and 5.0+/-2.9 (TIII, n=3), respectively, with no significant differences (P > or =0.05) among groups. Pregnancy rates of 62.2% (TI, n=235); 66.4% (TII, n=284) and 65.1% (TIII, n=244) were obtained with embryos transferred from these collections and did not differ significantly (P > or =0.05) among groups. It was concluded that the synchronization of the emergence of follicular waves in Nelore donors is usable and does not harm the efficiency of embryo transfer programs. In addition, in contrast to the standard superovulation protocol, this method permits the use of a large number of donors in a short time period, at any stage of the estrus cycle, minimizing the costs of embryo transfer.

Determination of molybdenum in steel by adsorptive stripping voltammetry in a homogeneous ternary solvent system.

A new alternative approach for the determination of molybdenum in steel is proposed, using adsorptive stripping voltammetry (AdSV). The determinations are performed in a homogeneous ternary solvent system (HTSS) composed of N,N-dimethylformamide, ethanol and water, with alpha-benzoinoxime (alpha BO) as the complexing agent and a sodium acetate-acetic acid buffer as the support electrolyte. The HTSS composition was optimized by mixture design modelling. The AdSV measurements were performed in the differential pulse mode using an accumulation potential of -1050 mV. Under these optimized experimental conditions, the Mo(VI)-alpha BO reduction current peak potential is observed at potentials near -1250 mV, much lower than those usually reported, and the calibration plot follows the polynomial equation I = 0.359 + 0.265 [CMo(VI)] - 0.015 [CMo(IV)]2 (r2 = 0.997), for Mo concentrations up to 10.0 micrograms L-1. There is a linear range in this calibration plot for Mo(VI) concentrations up to 0.20 microgram L-1, defined by the equation I = 0.353 + 0.385 [CMo(VI)] (r2 = 0.980). In both cases, I is the absolute value for the current in microA and CMo(VI) is the concentration of Mo in microgram L-1. The detection limit for this linear concentration range was estimated as 20 pg L-1. A RSD of 0.43% is associated with the signals at a Mo(VI) level of 0.72 microgram L-1. From the common method-interfering species tested, only iron at Fe/Mo(VI) ratios above 500 and vanadium and tungsten at M/Mo(VI) ratios above 100 appear to affect the analytical response significantly. Phosphorous may also reduce the analytical signal at P/Mo(VI) ratios above 100, due to the formation of the competitive P-Mo complex. The suggested routine procedure was tested by analyzing four stainless steel samples and the results compared well with the ICP-AES measurements. The higher sensitivity of this method permits direct determination of Mo(VI) in steels, eliminating the need of analyte concentration or separation steps in the sample processing procedure.

[Surgical treatment of colorectal cancer. 10-year experience at the INCMNSZ]. / Tratamiento quirúrgico del cáncer colorrectal. Experiencia de 10 años en el INCMNSZ.

OBJECTIVE: To analyze the short- and long-term outcomes of the surgical treatment for colorectal cancer at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ) in Mexico City. BACKGROUND: Colorectal cancer is the second most frequent malignant tumor of the digestive tract in Mexico. Its incidence is rising, and its identification in early stages is important to offer a curative surgical treatment. METHODS: Retrospective, descriptive observational trial. We studied 165 patients who underwent colorectal surgery for treatment of cancer between 1985 and 1994 at the INCMNSZ. We compared the variables of patients and the surgical procedures and their relationship with morbidity and mortality with 5-year survival. RESULTS: Survival was greater in curative-attempting procedures of the colon than of the rectum (p < 0.05). Survival rate was also greater in earlier stages of the disease at the moment of diagnosis. Surgical morbidity occurred in 30% due to wound infections in most cases. Mortality rate was 3.6%, while the main cause was sepsis. Patients > 65 years of age had a higher mortality rate. Rectal surgery had higher morbidity than colonic surgery. CONCLUSIONS: Detecting patients at earlier stages of the disease is required to offer them a curative-attempting surgery procedure. Stage at moment of diagnosis correlates with survival rates. Age was a risk factor for surgical mortality, and rectal surgery, a risk factor for morbidity.