14 research outputs found

    Evaluation of Scrotal Temperature in Different Testicular Shapes by Infrared Thermography in Braford Bulls

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    Background: The mechanisms of testicular thermoregulation may influence the blood flow provided by the testicular artery, where the proper blood supply to the testicle is crucial for promotingspermatogenesis and reproductive function in bulls. The size and shape of the testicles are determined by genetic mechanisms and environmental effects. A better understanding of the relationships between the anatomical characteristics of the testicles and scrotum can support a better reproductive assessment. The purpose of the current study was to evaluate the testicular temperature of different scrotal shapes using infrared thermography in bulls.Materials, Methods & Results: We evaluated 132 Braford bulls with an average age of 24 months. The evaluation of breeding bull semen was performed prior to the beginning of the experiment. Then, animals were selected on the basis of the size of their testes, which was determined by dividing the average width by the average length. The scrotal circumference was measured with a millimeter tape positioned around the largest circumference. Testicular and ocular temperature measurements and analysis were conducted using an infrared thermal camera, Flir T440 with emissivity of 0.98 and thermal sensitivity of 0.05°C. Testicular scrotum temperature and testicular shape were analyzed with one-way ANOVA using Minitab 16, and values of P < 0.05 were considered statistically significant. We observed that 67.42% of testicle shapes were long-oval, and 32.58% were long-moderate. The testicular temperature was higher in bulls with the long-moderate shape compared to those with the long-oval shape (P < 0.05). The mean length was higher in long-moderate shaped testicles compared to those of the long-oval shape (P < 0.01). There was no significant differences in rectal and ocular temperatures or in scrotal circumference between bulls with long-moderate and long-oval shapes (P > 0.05). In addition, the mean width was lower in testicles of long-moderate shape compared to those of the long-oval scrotal format (P < 0.01).Discussion: The results obtained showed that Braford bulls with the long-moderate testicular shape have a higher testicular temperature to maintain proper thermoregulation. The present study demonstrated that IRT can be used to evaluate the testicular temperature in animals with different scrotal conformations. In this study, Braford bulls showed lower length and width values for animals having long-moderate (9.21 and 5.22, respectively) and long-oval formats (8.56 and 5.56, respectively). In contrast, previous reports examining Nellore bulls between the ages of 17-20 months found a predominance of the long oval shape followed by the long-moderate shape, which indicates a change in testicular shape as age progresses, resulting in a rounder testicular shape. Perhaps other factors, such as the external cremaster muscle and tunica dartos, cause the testicles to be retracted towards the body at lower temperatures while at high temperatures, relaxation occurs. The prevailing testicular shape in Braford animals with a mean age of 24 months was the long-moderate shape. Thus, testicles with a larger surface area will have lower temperatures because they can dissipate heat more easily than testicles with lower surface area. The results suggest that the long-moderate scrotum format may influence the testicular temperature in mature Braford bulls

    Synthèse de nouveaux "Covalent Triazine Frameworks" pour la photoréduction du dioxyde de carbone

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    Using sunlight as a renewable source of energy to promote carbon dioxide (CO2) conversion is an interesting approach to address sustainable chemicals and fuels production as well as mitigation of climate change. However, in most photocatalytic systems, the utilization of a homogeneous photosensitizer represents a key limitation for long-term reactions due to its low stability. Therefore, novel, more efficient and stable photocatalyst materials and photocatalytic processes are required. Here, the strategy of structuration at the molecular-level of CTF photocatalysts is presented, seeking to enhance their long-term stability. The integration of photo-active centers into a molecularly defined support improve their photocatalytic stability. Moreover, the incorporation of chelating moieties, such as bipyridine, offers a unique possibility for heterogenization of organometallic complex, profiting at the same time from enhanced selectivity and activity from the molecular catalyst and easy handling and separation from its heterogeneous nature. Macroligands, a solid acting like the ligand in the corresponding molecular complex, is a pivotal strategy to bridge the gap between homogeneous and heterogeneous catalysis.In this thesis, the synthesis of simple CTFs through condensation was done in order to optimize the parameters and highlight the main advantages and drawbacks of this method. Additionally, the approach was extended to the synthesis of functionalized materials, based on bipyridine ligands. Using the strategy of modular design, the content of a ligand within the framework was precisely controlled for the first time. Additionally, by judiciously chosen the proper tailored precursor and its content, it is possible to carefully control properties like light absorption and porosity, pushing the boundaries of molecular control on the synthesis of CTFs. In this regard, CTFs based on bipyridine were precisely designed in order to contain both, a photoactive moiety and a chelating site for the heterogenization of molecular catalysts within the structure. In our all-in-one concept, a (Cp*)-Rhodium complex was heterogenized within CTFs macroligands containing different amounts of bipyridine. Those materials catalyze the carbon dioxide photoreduction to formate, driven by visible light at TOFs around 4 h-1L'utilisation de la lumière solaire comme source d'énergie renouvelable pour promouvoir la conversion du dioxyde de carbone (CO2) est une approche intéressante pour aborder la production durable de produits chimiques et de combustibles ainsi que pour lutter contre le dérèglement climatique. Cependant, dans la plupart des systèmes photocatalytiques, l'utilisation d'un photosensibilisateur homogène représente une limitation clé pour les réactions à long terme en raison de sa faible stabilité. Par conséquent, de nouveaux matériaux photocatalyseurs et processus photocatalytiques plus efficaces et stables sont nécessaires. Ici, la stratégie de structuration au niveau moléculaire des photocatalyseurs CTF est présentée, cherchant à améliorer leur stabilité à long terme. L'intégration de centres photoactifs dans un support moléculaire défini améliore leur stabilité photocatalytique. De plus, l'incorporation de fractions chélatantes, telles que la bipyridine, offre une possibilité unique d'hétérogénéisation de complexes organométalliques, bénéficiant à la fois d'une sélectivité et d'une activité améliorées comparées au catalyseur moléculaire analogue et d'une manipulation et d'une séparation facile grâce à sa nature hétérogène. L’utlisation de macroligand, solides agissant comme le ligand dans le complexe moléculaire correspondant, est une stratégie attrayante pour combler l'écart entre la catalyse homogène et hétérogène. Dans cette thèse, la synthèse de CTF simple par condensation a été réalisée afin d'optimiser les paramètres et de mettre en évidence les principaux avantages et inconvénients de cette méthode. De plus, l'approche a été étendue à la synthèse de matériaux fonctionnalisés, basés sur des ligands bipyridiniques. En utilisant la stratégie de conception modulaire, le contenu d'un ligand dans le matériaux a été précisément contrôlé pour la première fois. De plus, en choisissant judicieusement le précurseur adapté et son contenu, il est possible de contrôler soigneusement les propriétés comme l'absorption de la lumière et la porosité, repoussant les limites du contrôle moléculaire sur la synthèse des CTF. À cet égard, les CTF basés sur la bipyridine ont été précisément conçus afin de contenir à la fois un fragment photoactif et un site de chélation pour l'hétérogénéisation des catalyseurs moléculaires au sein de la structure. Dans notre concept tout-en-un, un complexe rhodium a été hétérogénéisé au sein de macroligands CTF contenant différentes quantités de bipyridine. Ces matériaux catalysent la photoréduction du dioxyde de carbone en formiate activée par la lumière visible avec des activité de l’ordre de 4 h-

    Synthesis of new Covalent Triazine Frameworks for Carbon Dioxide Photoreduction

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    L'utilisation de la lumière solaire comme source d'énergie renouvelable pour promouvoir la conversion du dioxyde de carbone (CO2) est une approche intéressante pour aborder la production durable de produits chimiques et de combustibles ainsi que pour lutter contre le dérèglement climatique. Cependant, dans la plupart des systèmes photocatalytiques, l'utilisation d'un photosensibilisateur homogène représente une limitation clé pour les réactions à long terme en raison de sa faible stabilité. Par conséquent, de nouveaux matériaux photocatalyseurs et processus photocatalytiques plus efficaces et stables sont nécessaires. Ici, la stratégie de structuration au niveau moléculaire des photocatalyseurs CTF est présentée, cherchant à améliorer leur stabilité à long terme. L'intégration de centres photoactifs dans un support moléculaire défini améliore leur stabilité photocatalytique. De plus, l'incorporation de fractions chélatantes, telles que la bipyridine, offre une possibilité unique d'hétérogénéisation de complexes organométalliques, bénéficiant à la fois d'une sélectivité et d'une activité améliorées comparées au catalyseur moléculaire analogue et d'une manipulation et d'une séparation facile grâce à sa nature hétérogène. L’utlisation de macroligand, solides agissant comme le ligand dans le complexe moléculaire correspondant, est une stratégie attrayante pour combler l'écart entre la catalyse homogène et hétérogène. Dans cette thèse, la synthèse de CTF simple par condensation a été réalisée afin d'optimiser les paramètres et de mettre en évidence les principaux avantages et inconvénients de cette méthode. De plus, l'approche a été étendue à la synthèse de matériaux fonctionnalisés, basés sur des ligands bipyridiniques. En utilisant la stratégie de conception modulaire, le contenu d'un ligand dans le matériaux a été précisément contrôlé pour la première fois. De plus, en choisissant judicieusement le précurseur adapté et son contenu, il est possible de contrôler soigneusement les propriétés comme l'absorption de la lumière et la porosité, repoussant les limites du contrôle moléculaire sur la synthèse des CTF. À cet égard, les CTF basés sur la bipyridine ont été précisément conçus afin de contenir à la fois un fragment photoactif et un site de chélation pour l'hétérogénéisation des catalyseurs moléculaires au sein de la structure. Dans notre concept tout-en-un, un complexe rhodium a été hétérogénéisé au sein de macroligands CTF contenant différentes quantités de bipyridine. Ces matériaux catalysent la photoréduction du dioxyde de carbone en formiate activée par la lumière visible avec des activité de l’ordre de 4 h-1Using sunlight as a renewable source of energy to promote carbon dioxide (CO2) conversion is an interesting approach to address sustainable chemicals and fuels production as well as mitigation of climate change. However, in most photocatalytic systems, the utilization of a homogeneous photosensitizer represents a key limitation for long-term reactions due to its low stability. Therefore, novel, more efficient and stable photocatalyst materials and photocatalytic processes are required. Here, the strategy of structuration at the molecular-level of CTF photocatalysts is presented, seeking to enhance their long-term stability. The integration of photo-active centers into a molecularly defined support improve their photocatalytic stability. Moreover, the incorporation of chelating moieties, such as bipyridine, offers a unique possibility for heterogenization of organometallic complex, profiting at the same time from enhanced selectivity and activity from the molecular catalyst and easy handling and separation from its heterogeneous nature. Macroligands, a solid acting like the ligand in the corresponding molecular complex, is a pivotal strategy to bridge the gap between homogeneous and heterogeneous catalysis.In this thesis, the synthesis of simple CTFs through condensation was done in order to optimize the parameters and highlight the main advantages and drawbacks of this method. Additionally, the approach was extended to the synthesis of functionalized materials, based on bipyridine ligands. Using the strategy of modular design, the content of a ligand within the framework was precisely controlled for the first time. Additionally, by judiciously chosen the proper tailored precursor and its content, it is possible to carefully control properties like light absorption and porosity, pushing the boundaries of molecular control on the synthesis of CTFs. In this regard, CTFs based on bipyridine were precisely designed in order to contain both, a photoactive moiety and a chelating site for the heterogenization of molecular catalysts within the structure. In our all-in-one concept, a (Cp*)-Rhodium complex was heterogenized within CTFs macroligands containing different amounts of bipyridine. Those materials catalyze the carbon dioxide photoreduction to formate, driven by visible light at TOFs around 4 h-

    Hormonal therapy in the senescence: Prostatic microenvironment structure and adhesion molecules

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    Hormonal replacement has been utilized to minimize the harmful effects of hormonal imbalance in elderly men. The development and progression of prostatic diseases and their relation to hormone therapy is still unclear. Thus, the aim herewith was to characterize the structure and dystroglycan molecule (DGs) reactivities in the ventral prostatic lobe from elderly rats submitted to steroid hormone replacement. Male rats (Sprague-Dawley) were divided into one Young group and six senile groups. The Young group (YNG) (4 months old) received peanut oil (5 mL/kg, s.c.). The senile rats (10 months old) were submitted to the following treatments: Senile group (SEN) (5 mL/kg peanut oil, s.c.); Testosterone group (TEST) (5 mg/kg testosterone cipionate, s.c.); Estrogen group (EST) (25 mu g/kg 17 beta-estradiol, s.c.); Castrated group (CAS) (surgical castration); Castrated-Testosterone (CT) (surgical castration and treatment similar to TEST group); and Castrated-Estrogen (CE) (surgical castration and treatment similar to EST group). After 30 days treatment, blood samples were collected for hormonal analysis and ventral prostate samples were processed for light and transmission electron microscopies, morphometrical analysis, immunohistochemistry and Western Blotting. The results showed decreased serum testosterone levels in the senescence and increased testosterone and estrogen plasmatic levels after hormone administration in the TEST and EST groups, respectively, highlighting the therapy efficiency. Hypertrophied stroma and inflammatory cells were verified in the SEN group. After hormone replacement in the senescence or following castration, atrophic epithelium, epithelial cells with clear cytoplasmic halo around the nucleus, microacini and maintenance of hypertrophied stroma were seen. Decreased DG levels were verified in the senescence. After hormonal therapy, increased protein levels of these molecules were observed, especially in those groups which received estradiol. Thus, the occurrence of inflammatory cells, stromal hypertrophy and the presence of cells with clear halo around the nucleus after hormonal therapy probably indicated prostatic paracrine signaling imbalance, suggesting a stromal reactive microenvironment favorable to the development of glandular lesions. However, the increase of DG levels characterized positive effect of steroid hormone replacement on the prostate in the senescence. Thus, it could be concluded that despite having positive effects on important molecules involved in the maintenance of epithelial-stromal interaction and glandular cytoarchitecture, such as DGs, hormonal therapy enhanced structural changes associated with senescence, probably due to increased hormonal imbalance between androgens and estrogens in the prostatic tissue. (C) 2011 Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Alcoholism and coagulating gland: Androgen and insulin like growth factor-1 receptor features

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    The aim of this work was to characterize the structural and molecular changes in the coagulating gland from rats submitted to long-term alcohol treatment, as well as the possibility of recovery of these parameters after interrupting the alcohol administration. Ten Wistar and twenty UChB rats were divided into: Control group received tap water; Alcoholic group received 10% (v/v) ethanol daily for 150 days; and Abstinent group, received 10% (v/v) ethanol daily for 120 days and then tap water like the control for another 30 days. After 150 days, samples from the coagulating glands were processed for morphological and immunohistochemical analyses. The results showed atrophied epithelium and hypertrophied stroma, especially in the alcoholic group. Intensed androgen receptor (AR) immunolocalization was verified in the epithelium and weak in the stroma of the control group in relation to the other groups. Intensed insulin-like growth factor receptor-1 (IGFR-1) immunolocalization was verified in the stroma of the alcoholic and abstinent groups. Thus, it could be concluded that the excessive alcohol consumption caused morphological and molecular changes in the coagulating gland, characterizing the inverse relation of AR and IGFR-1 localization. The alcohol was an important factor in cellular mitosis occurrence, which could be fundamental element involved in glandular lesions. (C) 2010 Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    An Aligned Framework of Actively-collected and Passively-monitored Clinical Outcome Assessments (COAs) for Measure Selection

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    Regulators and payers increasingly require Clinical Outcome Assessment (COA) data for approval and reimbursement. COAs can be collected actively or passively, yet no single resource provides a side-by-side comparison of tools that collect complementary or related COA measures. We propose how to align ontologies for actively-collected and passively-monitored COAs into a single framework to allow for rapid, evidence-based, and fit-for-purpose measure selection

    Recombinant protein-based nanocarriers and their association with cationic liposomes: Characterization and in vitro evaluation

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    A major bottleneck in the development of efficient protocols for gene therapy and DNA vaccination is the low efficiency of gene transfer by non-viral vectors. This is mainly attributed to the fact that, during the traffic to target cell nuclei, vectors must overcome a series of enzymatic, physical, and diffusional barriers. The objective of this work was the development and characterization of new multifunctional non-viral vectors, based on proteins and lipids, that are able to efficiently deliver the foreign plasmid DNA (pDNA) to the nucleus of mammalian cells. A model pDNA containing the reporter gene GFP was complexed to protamine or the recombinant modular protein T-Rp3 to form binary complexes. In addition, we studied the ability of the cationic liposome composed of EPC/DOPE/DOTAP to encapsulate the binary complexes to form pseudo-ternary complexes (pDNA/protein/liposome). Characterization of the complexes were performed by dynamic light scattering (DLS), zeta potential, transmission electron microscopy (TEM) and pDNA accessibility assay. The assays revealed that both proteins were able to condense pDNA and form positively charged complexes, that could be efficiently encapsulated, leading to the formation of pDNA/protein/liposome complexes. Transfection studies using HeLa cells indicated that pDNA/protein formed by T-Rp3 were far more efficient for pDNA delivery than protamine. The complexes formed by pDNA/T-Rp3/liposome presented the highest transfection level (25%). On the other hand, cytotoxicity assays showed a significant decrease on cell viability when using pDNA/T-Rp3/liposome, indicating that the association of T-Rp3 with liposome significantly increase the delivery efficiency whilst prompting a proportional negative impact on cytotoxicity. A better understanding of the mechanisms of cell uptake and intracellular trafficking regarding the synergic effect between proteins and lipids in these vectors may, in the near future, lead to the development of more efficient non-viral vectors able to mimic the abilities of viral nucleic acid delivery513110CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP471971/2011-1; 444412/2014-02007/58323-9; 2013/23780-1; 2012/23143-9; 2013/05969-

    Heterogenization of a Molecular Ni Catalyst within a Porous Macroligand for the Direct C-H Arylation of Heteroarenes

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    International audienceDirect C–H functionalization catalyzed by a robust and recyclable heterogeneous catalyst is highly desirable for sustainable fine chemical synthesis. Bipyridine units covalently incorporated into the backbone of a porous organic polymer were used as a porous macroligand for the heterogenization of a molecular nickel catalyst. A controlled nickel loading within the porous macroligand is achieved, and the nickel coordination to the bipyridine (bpy) sites is assessed at the molecular level using IR and solid-state NMR spectroscopy. The heterogenized Ni-bpy catalyst was successfully applied to the direct and fully selective C2 arylation of benzothiophenes, thiophene, and selenophene, as well as for the arylation of free NH-indole. Recyclability of the catalyst was achieved by employing hydride activators to reach a cumulative turnover number of more than 300 after seven cycles of catalysis, which corresponds to a total productivity of 12 g of 2-phenylbenzothiophene, chosen as model target biaryl, per gram of catalyst

    Africa and China: a strategic partnership?

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    Relations between Africa and China have increased over the years and become more dominated by China's economic interests. With an annual growth rate of 8-9 per cent, and a booming economy, China's dependency on accessing natural resources is a top priority and has accordingly expanded its horizons. Africa, with all its seemingly unlimited natural resources, is an ideal partner. In addition, the African continent as a whole offers a potential market for China's low-value manufactured commodities. This paper is an attempt to present an overview of contemporary Sino-African relations and the state of trade relations, with special emphasis on natural resources and the export market for Chinese products and investments in Afric
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