This cross-sectional study describes the occurrences of maltreatment recorded over three years (1... more This cross-sectional study describes the occurrences of maltreatment recorded over three years (1997-1999) in a Brazilian Police Department for the Protection of the Child and the Adolescent. Socio-demographic and physical data of victims, aggressors and denouncers were investigated in a sample consisting of 2073 cases. The victims were aged between 0-18 years, of which 56.1% were girls. Data were entered into EPI INFO 2000 software and analyzed using descriptive statistics and chi-square test to determine significant differences (p<0.05). All manifestations of abuse, except physical abuse, tend to occur more frequently in females, and tend to be more prevalent in the 11-to-15 year-old subgroup. Physical abuse was the most common offense (64.7%). Injuries of face and jaw were found in 65.3% of the cases. Most of the aggressors were males (71.8%). There was a positive correlation between gender (female) and sexual abuse. Physical violence against boys was more intensive, as indicated by the presence of more severe body lesions. Health professionals should increase their diagnostic skills and raise the awareness of their communities to take action for reducing the incidence and the impact of violence upon children and adolescents.
A.; PUGLIESE, L. S.; REIS, S. R. de A. Contribuição ao estudo da cárie dentária em crianças de 0-... more A.; PUGLIESE, L. S.; REIS, S. R. de A. Contribuição ao estudo da cárie dentária em crianças de 0-30 meses. Pesqui Odontol Bras, v. 15, n. 3, p. 215-222, jul./set. 2001. Este estudo avaliou as condições de saúde bucal de 340 crianças de 0-30 meses de idade (21,3 ± 5,6), sendo 54,4% meninos, 45,6% meninas, de 20 creches de Salvador, considerando lesões incipientes e relacionando-as a alguns fatores determinantes da cárie. Os exames foram realizados por um único examinador utilizando-se espelho, sonda e lanterna. Os dentes foram limpos, secos com gaze e as lesões classificadas de acordo com o grau de severidade em cinco níveis (C0-C4; ativa/inativa). Um questionário avaliou o conhecimento sobre a cárie, fatores de risco, instrução, renda familiar e uso de flúor. Foram incluídos 229 questionários (67,35%). A análise dos dados foi realizada no Epi-info 6.02. Observou-se uma prevalência de cárie de 55,3% quando todos os estágios da lesão foram considerados: 25% entre 0-12 meses; 51,18% entre 13-24 meses; 71,03% entre 25-30 meses (χ 2 = 25,31; p < 0,01). Avaliando-se apenas manchas brancas ativas, 49,7% das crianças mostraram-se afetadas e 17,6%, apenas com lesões cavitadas. Das crianças afetadas, 90,96% apresentavam apenas dentes anteriores afetados: 80% das lesões eram incipientes e 20%, cavitadas. Não foi observada diferença significante entre sexos. O aumento da quantidade de biofilme dental mostrou associação positiva com a cárie nesta faixa etária (χ 2 = 67,61; p < 0,01) e a porcentagem de crianças afetadas mostrou-se maior na presença de aleitamento noturno (χ 2 = 0,24; p = 0,62). Foi observado um aumento da prevalência de cárie com a idade (χ 2 = 25,31; p < 0,01) e com o número de dentes irrompidos ( χ 2 = 122,95; p < 0,01). Sugere-se atenção precoce à saúde bucal para o diagnóstico de lesões incipientes e adoção de medidas educativas e preventivas, incentivando mudanças na higiene bucal e dieta.
The native CD34+/CD31− cell population present in the stroma-vascular fraction of human adipose t... more The native CD34+/CD31− cell population present in the stroma-vascular fraction of human adipose tissue (hAT) displays progenitor cell properties since they exhibit adipocyte- and endothelial cell-like phenotypes under appropriate stimuli. To analyze the signals within hAT regulating their phenotypes, the influence of hAT-derived capillary endothelial cells (CECs) was studied on the chemotaxis and differentiation of the hAT-CD34+/CD31− cells. Conditioned medium from hAT-CECs led to a strong chemotaxis of the hAT-CD34+/CD31− cells that was inhibited with pretreatments with pertussis toxin, CXCR-4 antagonist, or neutralizing antibodies. Furthermore, hAT-CECs produced and secreted the CXCR-4 ligand, that is, the stromal derived factor-1 (SDF-1). Finally, hAT-CECs induced the differentiation of hAT-CD34+/CD31− cells toward an endothelial cell (EC) phenotype. Indeed, hAT-CECs and -CD34+/CD31− cell coculture stimulated in a two-dimensional system the expression of the EC CD31 marker by the hAT-progenitor cells and, in a three-dimensional approach, the formation of capillary-like structures via a SDF-1/CXCR-4 dependent pathway. Thus, the migration and differentiation of hAT progenitor cells are modulated by hAT-CEC-derived factors. SDF-1, which is secreted by hAT-derived CECs, and its receptor CXCR-4, expressed by hAT-derived progenitor cells, may promote chemotaxis and differentiation of hAT-derived progenitor cells and thus contribute to the formation of the vascular network during the development of hAT.Disclosure of potential conflicts of interest is found at the end of this article.
Journal of Pharmacology and Experimental Therapeutics, 2006
In a previous publication, we reported that human immunodeficiency virus (HIV) protease inhibitor... more In a previous publication, we reported that human immunodeficiency virus (HIV) protease inhibitors (PIs) inhibited the differentiation of human preadipocytes in primary culture, reducing the expression and secretion of matrix metalloproteinase 9 (MMP-9). The present work was performed to clarify this mechanism. Interestingly, HIV-PIs have been reported to be inhibitors of the proteasome complex, which is known to regulate nuclear factor (NF)-B activation and transcription of its target genes, among them MMP-9. We thus investigated the potential involvement of the proteasome in the antiadipogenic effects of HIV-PIs. The effect of four HIV-PIs was tested on preadipocyte proteasomal activity, and chronic treatment with the specific proteasome inhibitor lactacystin was performed to evaluate alterations of adipogenesis and MMP-9 expression/secretion. Finally, modifications of the NF-B pathway induced by either HIV-PIs or lactacystin were studied. We demonstrated that preadipocyte proteasomal activity was decreased by several HIV-PIs and that chronic treatment with lactacystin mimicked the effects of HIV-PIs by reducing adipogenesis and MMP-9 expression/secretion. Furthermore, we observed an intracellular accumulation of the NF-B inhibitor, IB, with chronic treatment with HIV-PIs or lactacystin as well as a decrease in MMP-9 expression induced by acute tumor necrosis factor-␣ stimulation. These results indicate that inhibition of the proteasome by specific (lactacystin) or nonspecific (HIV-PIs) inhibitors leads to a reduction of human adipogenesis, and they therefore implicate deregulation of the NF-B pathway and the related decrease of the key adipogenic factor, MMP-9. This study adds significantly to recent reports that have linked HIV-PI-related lipodystrophic syndrome with altered proteasome function, endoplasmic reticulum stress, and metabolic disorders.
Several laboratories have shown that the cells from the stroma-vascular fraction of the human adi... more Several laboratories have shown that the cells from the stroma-vascular fraction of the human adipose tissue express, depending on cell culture conditions, biochemical markers of multiple cell lineages including adipogenic, osteogenic, chondrogenic, myogenic, endothelial, neuronal and epithelial cell lineage. Furthermore, various in vivo approaches revealed the ability of the cells derived from the stroma-vacsular fraction of adipose tissue to repair
Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because th... more Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because they have been shown to accumulate with an increase in fat mass and to be involved in the genesis of insulin resistance in obese mice. However, the phenotype and functions of human ATMs are still to be defined. Methods and Results-The present study, performed on human subcutaneous AT, showed that ATMs from lean to overweight individuals are composed of distinct macrophage subsets based on the expression of several cell surface markers: CD45, CD14, CD31, CD44, HLA-DR, CD206, and CD16, as assessed by flow cytometry. ATMs isolated by an immunoselection protocol showed a mixed expression of proinflammatory (tumor necrosis factor-␣, interleukin-6 [IL-6], IL-23, monocyte chemoattractant protein-1, IL-8, cyclooxygenase-2) and antiinflammatory (IL-10, transforming growth factor-, alternative macrophage activation-associated cc chemokine-1, cyclooxygenase-1) factors. Fat mass enlargement is associated with accumulation of the CD206 ϩ /CD16 Ϫ macrophage subset that exhibits an M2 remodeling phenotype characterized by decreased expression of proinflammatory IL-8 and cyclooxygenase-2 and increased expression of lymphatic vessel endothelial hyaluronan receptor-1. ATMs specifically produced and released matrix metalloproteinase-9 compared with adipocytes and capillary endothelial cells, and secretion of matrix metalloproteinase-9 from human AT in vivo, assessed by arteriovenous difference measurement, was correlated with body mass index. Finally, ATMs exerted a marked proangiogenic effect on AT-derived endothelial and progenitor cells. Conclusions-The present results showed that the ATMs that accumulate with fat mass development exhibit a particular M2 remodeling phenotype. ATMs may be active players in the process of AT development through the extension of the capillary network and in the genesis of obesity-associated cardiovascular pathologies. (Circulation. 2008;117:806-815.)
Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because th... more Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because they have been shown to accumulate with an increase in fat mass and to be involved in the genesis of insulin resistance in obese mice. However, the phenotype and functions of human ATMs are still to be defined. Methods and Results-The present study, performed on human subcutaneous AT, showed that ATMs from lean to overweight individuals are composed of distinct macrophage subsets based on the expression of several cell surface markers: CD45, CD14, CD31, CD44, HLA-DR, CD206, and CD16, as assessed by flow cytometry. ATMs isolated by an immunoselection protocol showed a mixed expression of proinflammatory (tumor necrosis factor-␣, interleukin-6 [IL-6], IL-23, monocyte chemoattractant protein-1, IL-8, cyclooxygenase-2) and antiinflammatory (IL-10, transforming growth factor-, alternative macrophage activation-associated cc chemokine-1, cyclooxygenase-1) factors. Fat mass enlargement is associated with accumulation of the CD206 ϩ /CD16 Ϫ macrophage subset that exhibits an M2 remodeling phenotype characterized by decreased expression of proinflammatory IL-8 and cyclooxygenase-2 and increased expression of lymphatic vessel endothelial hyaluronan receptor-1. ATMs specifically produced and released matrix metalloproteinase-9 compared with adipocytes and capillary endothelial cells, and secretion of matrix metalloproteinase-9 from human AT in vivo, assessed by arteriovenous difference measurement, was correlated with body mass index. Finally, ATMs exerted a marked proangiogenic effect on AT-derived endothelial and progenitor cells. Conclusions-The present results showed that the ATMs that accumulate with fat mass development exhibit a particular M2 remodeling phenotype. ATMs may be active players in the process of AT development through the extension of the capillary network and in the genesis of obesity-associated cardiovascular pathologies. (Circulation. 2008;117:806-815.)
The results of a preliminary investigation of a series of polymer electrolytes based on a novel p... more The results of a preliminary investigation of a series of polymer electrolytes based on a novel polymer host, poly(trimethylene carbonate) or p(TMC), with lithium triflate or lithium perchlorate and various plasticizing additives, are described in this presentation. Electrolytes with lithium salt compositions of about n = 10 (where n represents the molar ratio of
The results of an investigation of a polymer electrolyte system based on the poly(trimethylene ca... more The results of an investigation of a polymer electrolyte system based on the poly(trimethylene carbonate) host matrix, designated as p(TMC), with lithium tetrafluoroborate guest salt are described in this presentation. Electrolytes with lithium salt compositions with n between 3 and 80 (where n represents the number of (O=COCH 2 CH 2 CH 2 O) units per lithium ion) were prepared by co-dissolution of salt and polymer in anhydrous tetrahydrofuran. The homogeneous solutions obtained by this procedure were evaporated, within a preparative glovebox and under a dry argon atmosphere, to form thin films of electrolyte.
Preparation of novel poly(alkylamine)-derived hydrogels is described. Polymers are prepared via r... more Preparation of novel poly(alkylamine)-derived hydrogels is described. Polymers are prepared via reaction of various diamines with dihalo compounds or diepoxides. N-substituted polymers are readily prepared by reaction of primary amines with dihalo compounds. The resulting covalently cross-linked polymers exhibit hydrogel behavior (high swell with water) when ionized to polyammonium species at low pH. At high pH, the polymers reside in the free base polyamine form and lose all hydrogel character (they no longer swell in water). Characterization of polymer structure with carbon-13 NMR, thermal analysis, and swell behavior reveals a structure which is highly branched and only loosely cross-linked. In the ionic polyammonium form thermal stability up to ∼300°C is observed. The polymers exhibit activity as bile acid sequestrants significantly superior to cholestyramine, as evidenced by their ability to efficiently bind quantities of cholate when tested in vitro. This behavior indicates that these hydrogels should be very useful for the treatment of hypercholesterolemia.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and c... more Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and containing a wide concentration range of potassium triflate, KCF3SO3, have been analyzed by x-ray diffraction and differential scanning calorimetry. The pseudo-phase diagram proposed has been taken into account in the interpretation of the complex impedance measurements. The xerogels prepared are obtained as transparent, thin monoliths. At room temperature the highest conductivity found was 2 × 10−6 Ω−1 cm−1.
A economia se ocupa das questões relativas a satisfação das necessidades dos indivíduos e da soci... more A economia se ocupa das questões relativas a satisfação das necessidades dos indivíduos e da sociedade.
This cross-sectional study describes the occurrences of maltreatment recorded over three years (1... more This cross-sectional study describes the occurrences of maltreatment recorded over three years (1997-1999) in a Brazilian Police Department for the Protection of the Child and the Adolescent. Socio-demographic and physical data of victims, aggressors and denouncers were investigated in a sample consisting of 2073 cases. The victims were aged between 0-18 years, of which 56.1% were girls. Data were entered into EPI INFO 2000 software and analyzed using descriptive statistics and chi-square test to determine significant differences (p<0.05). All manifestations of abuse, except physical abuse, tend to occur more frequently in females, and tend to be more prevalent in the 11-to-15 year-old subgroup. Physical abuse was the most common offense (64.7%). Injuries of face and jaw were found in 65.3% of the cases. Most of the aggressors were males (71.8%). There was a positive correlation between gender (female) and sexual abuse. Physical violence against boys was more intensive, as indicated by the presence of more severe body lesions. Health professionals should increase their diagnostic skills and raise the awareness of their communities to take action for reducing the incidence and the impact of violence upon children and adolescents.
A.; PUGLIESE, L. S.; REIS, S. R. de A. Contribuição ao estudo da cárie dentária em crianças de 0-... more A.; PUGLIESE, L. S.; REIS, S. R. de A. Contribuição ao estudo da cárie dentária em crianças de 0-30 meses. Pesqui Odontol Bras, v. 15, n. 3, p. 215-222, jul./set. 2001. Este estudo avaliou as condições de saúde bucal de 340 crianças de 0-30 meses de idade (21,3 ± 5,6), sendo 54,4% meninos, 45,6% meninas, de 20 creches de Salvador, considerando lesões incipientes e relacionando-as a alguns fatores determinantes da cárie. Os exames foram realizados por um único examinador utilizando-se espelho, sonda e lanterna. Os dentes foram limpos, secos com gaze e as lesões classificadas de acordo com o grau de severidade em cinco níveis (C0-C4; ativa/inativa). Um questionário avaliou o conhecimento sobre a cárie, fatores de risco, instrução, renda familiar e uso de flúor. Foram incluídos 229 questionários (67,35%). A análise dos dados foi realizada no Epi-info 6.02. Observou-se uma prevalência de cárie de 55,3% quando todos os estágios da lesão foram considerados: 25% entre 0-12 meses; 51,18% entre 13-24 meses; 71,03% entre 25-30 meses (χ 2 = 25,31; p < 0,01). Avaliando-se apenas manchas brancas ativas, 49,7% das crianças mostraram-se afetadas e 17,6%, apenas com lesões cavitadas. Das crianças afetadas, 90,96% apresentavam apenas dentes anteriores afetados: 80% das lesões eram incipientes e 20%, cavitadas. Não foi observada diferença significante entre sexos. O aumento da quantidade de biofilme dental mostrou associação positiva com a cárie nesta faixa etária (χ 2 = 67,61; p < 0,01) e a porcentagem de crianças afetadas mostrou-se maior na presença de aleitamento noturno (χ 2 = 0,24; p = 0,62). Foi observado um aumento da prevalência de cárie com a idade (χ 2 = 25,31; p < 0,01) e com o número de dentes irrompidos ( χ 2 = 122,95; p < 0,01). Sugere-se atenção precoce à saúde bucal para o diagnóstico de lesões incipientes e adoção de medidas educativas e preventivas, incentivando mudanças na higiene bucal e dieta.
The native CD34+/CD31− cell population present in the stroma-vascular fraction of human adipose t... more The native CD34+/CD31− cell population present in the stroma-vascular fraction of human adipose tissue (hAT) displays progenitor cell properties since they exhibit adipocyte- and endothelial cell-like phenotypes under appropriate stimuli. To analyze the signals within hAT regulating their phenotypes, the influence of hAT-derived capillary endothelial cells (CECs) was studied on the chemotaxis and differentiation of the hAT-CD34+/CD31− cells. Conditioned medium from hAT-CECs led to a strong chemotaxis of the hAT-CD34+/CD31− cells that was inhibited with pretreatments with pertussis toxin, CXCR-4 antagonist, or neutralizing antibodies. Furthermore, hAT-CECs produced and secreted the CXCR-4 ligand, that is, the stromal derived factor-1 (SDF-1). Finally, hAT-CECs induced the differentiation of hAT-CD34+/CD31− cells toward an endothelial cell (EC) phenotype. Indeed, hAT-CECs and -CD34+/CD31− cell coculture stimulated in a two-dimensional system the expression of the EC CD31 marker by the hAT-progenitor cells and, in a three-dimensional approach, the formation of capillary-like structures via a SDF-1/CXCR-4 dependent pathway. Thus, the migration and differentiation of hAT progenitor cells are modulated by hAT-CEC-derived factors. SDF-1, which is secreted by hAT-derived CECs, and its receptor CXCR-4, expressed by hAT-derived progenitor cells, may promote chemotaxis and differentiation of hAT-derived progenitor cells and thus contribute to the formation of the vascular network during the development of hAT.Disclosure of potential conflicts of interest is found at the end of this article.
Journal of Pharmacology and Experimental Therapeutics, 2006
In a previous publication, we reported that human immunodeficiency virus (HIV) protease inhibitor... more In a previous publication, we reported that human immunodeficiency virus (HIV) protease inhibitors (PIs) inhibited the differentiation of human preadipocytes in primary culture, reducing the expression and secretion of matrix metalloproteinase 9 (MMP-9). The present work was performed to clarify this mechanism. Interestingly, HIV-PIs have been reported to be inhibitors of the proteasome complex, which is known to regulate nuclear factor (NF)-B activation and transcription of its target genes, among them MMP-9. We thus investigated the potential involvement of the proteasome in the antiadipogenic effects of HIV-PIs. The effect of four HIV-PIs was tested on preadipocyte proteasomal activity, and chronic treatment with the specific proteasome inhibitor lactacystin was performed to evaluate alterations of adipogenesis and MMP-9 expression/secretion. Finally, modifications of the NF-B pathway induced by either HIV-PIs or lactacystin were studied. We demonstrated that preadipocyte proteasomal activity was decreased by several HIV-PIs and that chronic treatment with lactacystin mimicked the effects of HIV-PIs by reducing adipogenesis and MMP-9 expression/secretion. Furthermore, we observed an intracellular accumulation of the NF-B inhibitor, IB, with chronic treatment with HIV-PIs or lactacystin as well as a decrease in MMP-9 expression induced by acute tumor necrosis factor-␣ stimulation. These results indicate that inhibition of the proteasome by specific (lactacystin) or nonspecific (HIV-PIs) inhibitors leads to a reduction of human adipogenesis, and they therefore implicate deregulation of the NF-B pathway and the related decrease of the key adipogenic factor, MMP-9. This study adds significantly to recent reports that have linked HIV-PI-related lipodystrophic syndrome with altered proteasome function, endoplasmic reticulum stress, and metabolic disorders.
Several laboratories have shown that the cells from the stroma-vascular fraction of the human adi... more Several laboratories have shown that the cells from the stroma-vascular fraction of the human adipose tissue express, depending on cell culture conditions, biochemical markers of multiple cell lineages including adipogenic, osteogenic, chondrogenic, myogenic, endothelial, neuronal and epithelial cell lineage. Furthermore, various in vivo approaches revealed the ability of the cells derived from the stroma-vacsular fraction of adipose tissue to repair
Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because th... more Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because they have been shown to accumulate with an increase in fat mass and to be involved in the genesis of insulin resistance in obese mice. However, the phenotype and functions of human ATMs are still to be defined. Methods and Results-The present study, performed on human subcutaneous AT, showed that ATMs from lean to overweight individuals are composed of distinct macrophage subsets based on the expression of several cell surface markers: CD45, CD14, CD31, CD44, HLA-DR, CD206, and CD16, as assessed by flow cytometry. ATMs isolated by an immunoselection protocol showed a mixed expression of proinflammatory (tumor necrosis factor-␣, interleukin-6 [IL-6], IL-23, monocyte chemoattractant protein-1, IL-8, cyclooxygenase-2) and antiinflammatory (IL-10, transforming growth factor-, alternative macrophage activation-associated cc chemokine-1, cyclooxygenase-1) factors. Fat mass enlargement is associated with accumulation of the CD206 ϩ /CD16 Ϫ macrophage subset that exhibits an M2 remodeling phenotype characterized by decreased expression of proinflammatory IL-8 and cyclooxygenase-2 and increased expression of lymphatic vessel endothelial hyaluronan receptor-1. ATMs specifically produced and released matrix metalloproteinase-9 compared with adipocytes and capillary endothelial cells, and secretion of matrix metalloproteinase-9 from human AT in vivo, assessed by arteriovenous difference measurement, was correlated with body mass index. Finally, ATMs exerted a marked proangiogenic effect on AT-derived endothelial and progenitor cells. Conclusions-The present results showed that the ATMs that accumulate with fat mass development exhibit a particular M2 remodeling phenotype. ATMs may be active players in the process of AT development through the extension of the capillary network and in the genesis of obesity-associated cardiovascular pathologies. (Circulation. 2008;117:806-815.)
Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because th... more Background-Adipose tissue macrophages (ATMs) have become a focus of attention recently because they have been shown to accumulate with an increase in fat mass and to be involved in the genesis of insulin resistance in obese mice. However, the phenotype and functions of human ATMs are still to be defined. Methods and Results-The present study, performed on human subcutaneous AT, showed that ATMs from lean to overweight individuals are composed of distinct macrophage subsets based on the expression of several cell surface markers: CD45, CD14, CD31, CD44, HLA-DR, CD206, and CD16, as assessed by flow cytometry. ATMs isolated by an immunoselection protocol showed a mixed expression of proinflammatory (tumor necrosis factor-␣, interleukin-6 [IL-6], IL-23, monocyte chemoattractant protein-1, IL-8, cyclooxygenase-2) and antiinflammatory (IL-10, transforming growth factor-, alternative macrophage activation-associated cc chemokine-1, cyclooxygenase-1) factors. Fat mass enlargement is associated with accumulation of the CD206 ϩ /CD16 Ϫ macrophage subset that exhibits an M2 remodeling phenotype characterized by decreased expression of proinflammatory IL-8 and cyclooxygenase-2 and increased expression of lymphatic vessel endothelial hyaluronan receptor-1. ATMs specifically produced and released matrix metalloproteinase-9 compared with adipocytes and capillary endothelial cells, and secretion of matrix metalloproteinase-9 from human AT in vivo, assessed by arteriovenous difference measurement, was correlated with body mass index. Finally, ATMs exerted a marked proangiogenic effect on AT-derived endothelial and progenitor cells. Conclusions-The present results showed that the ATMs that accumulate with fat mass development exhibit a particular M2 remodeling phenotype. ATMs may be active players in the process of AT development through the extension of the capillary network and in the genesis of obesity-associated cardiovascular pathologies. (Circulation. 2008;117:806-815.)
The results of a preliminary investigation of a series of polymer electrolytes based on a novel p... more The results of a preliminary investigation of a series of polymer electrolytes based on a novel polymer host, poly(trimethylene carbonate) or p(TMC), with lithium triflate or lithium perchlorate and various plasticizing additives, are described in this presentation. Electrolytes with lithium salt compositions of about n = 10 (where n represents the molar ratio of
The results of an investigation of a polymer electrolyte system based on the poly(trimethylene ca... more The results of an investigation of a polymer electrolyte system based on the poly(trimethylene carbonate) host matrix, designated as p(TMC), with lithium tetrafluoroborate guest salt are described in this presentation. Electrolytes with lithium salt compositions with n between 3 and 80 (where n represents the number of (O=COCH 2 CH 2 CH 2 O) units per lithium ion) were prepared by co-dissolution of salt and polymer in anhydrous tetrahydrofuran. The homogeneous solutions obtained by this procedure were evaporated, within a preparative glovebox and under a dry argon atmosphere, to form thin films of electrolyte.
Preparation of novel poly(alkylamine)-derived hydrogels is described. Polymers are prepared via r... more Preparation of novel poly(alkylamine)-derived hydrogels is described. Polymers are prepared via reaction of various diamines with dihalo compounds or diepoxides. N-substituted polymers are readily prepared by reaction of primary amines with dihalo compounds. The resulting covalently cross-linked polymers exhibit hydrogel behavior (high swell with water) when ionized to polyammonium species at low pH. At high pH, the polymers reside in the free base polyamine form and lose all hydrogel character (they no longer swell in water). Characterization of polymer structure with carbon-13 NMR, thermal analysis, and swell behavior reveals a structure which is highly branched and only loosely cross-linked. In the ionic polyammonium form thermal stability up to ∼300°C is observed. The polymers exhibit activity as bile acid sequestrants significantly superior to cholestyramine, as evidenced by their ability to efficiently bind quantities of cholate when tested in vitro. This behavior indicates that these hydrogels should be very useful for the treatment of hypercholesterolemia.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and c... more Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and containing a wide concentration range of potassium triflate, KCF3SO3, have been analyzed by x-ray diffraction and differential scanning calorimetry. The pseudo-phase diagram proposed has been taken into account in the interpretation of the complex impedance measurements. The xerogels prepared are obtained as transparent, thin monoliths. At room temperature the highest conductivity found was 2 × 10−6 Ω−1 cm−1.
A economia se ocupa das questões relativas a satisfação das necessidades dos indivíduos e da soci... more A economia se ocupa das questões relativas a satisfação das necessidades dos indivíduos e da sociedade.
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