Development and validation of a dissolution test for lodenafil carbonate based on in vivo data

Introduction: Lodenafil carbonate is a phosphodiesterase type 5 inhibitor used for the treatment of erectile dysfunction. Currently, there is no dissolution test reported for lodenafil carbonate and this drug is not listed in any pharmacopoeia.

Objective: The present study focused on the development and validation of a dissolution test for lodenafil carbonate tablets, using a simulated absorption profile based on in vivo data.

Methods: The appropriate conditions were determined after testing sink conditions. Different conditions as medium, surfactant concentration and rotation speed were evaluated. The percentage of dose absorbed was calculated by deconvolution, using the Wagner–Nelson method.

Results: According to the obtained results, the use of 0.1?M HCl?+?1.5% SLS (900?mL, at 37?+?0.5?°C) as the dissolution medium, paddles at 25?rpm were considered adequate. The samples were quantified by UV spectroscopy at 295?nm and the validation was performed according to international guidelines. The method showed specificity, linearity, accuracy and precision, within the acceptable range. Kinetics of drug release was better described by the first-order model.

Conclusion: The proposed dissolution test can be used for the routine quality control of lodenafil carbonate in tablets.     

Sperm surface changes and physiological consequences induced by sperm handling and storage

Spermatozoa interact with their immediate environment and this contact remodels the sperm surface in preparation for fertilisation. These fundamental membrane changes will be critically covered in this review with special emphasis on the very specific surface destabilisation event, capacitation. This process involves very subtle and intricate modifications of the sperm membrane including removal of suppression (decapacitation) factors and changes in the lateral organisation of the proteins and lipids of the sperm surface. Processing of sperm for assisted reproduction (storage, sex-sorting, etc.) subjects spermatozoa to numerous stressors, and it is possible that this processing overrides such delicate processes resulting in sperm instability and cell damage. To improve sperm quality, novel mechanisms must be used to stabilise the sperm surface during handling. In this review, different types of membrane stress are considered, as well as novel surface manipulation methods to improve sperm stability.     

Antimicrobial resistance of heterotrophic bacteria in sewage-contaminated rivers

Sewage-contaminated rivers are ecosystems deeply disturbed by human activity due to the release of heavy metals, organic pollutants and pharmaceuticals as well as faecal and pathogenic micro-organisms, which coexist with the autochthonous microbial population. In this study, we compared the percentage of resistance in faecal and heterotrophic bacteria in rivers with different degrees of sewage pollution. As a matter of fact, no correlation was found neither between the degree of sewage pollution and the percentage of antimicrobial resistant heterotrophic bacteria nor between the number of resistant faecal bacteria and that of resistant heterotrophic bacteria. Most of the resistant isolates from the Zenne river downstream Brussels were multi-resistant and the resistance patterns were similar among the strains of each phylogenetic group. The total microbial community in this polluted river (as evaluated through a 16S rRNA gene clone library analysis) appeared to be dominated by the phyla Proteobacteria and Bacteroidetes while the phylum TM7 was the third most represented.     

Carbon‐Based Anodes for Lithium Sulfur Full Cells with High Cycle Stability

The lithium sulfur battery system has been studied since the late 1970s and has seen renewed interest in recent years. However, even after three decades of intensive research, prolonged cycling can only be achieved when a large excess of electrolyte and lithium is used. Here, for the first time, a balanced and stable lithium sulfur full cell is demonstrated with silicon–carbon as well as all‐carbon anodes. More than 1000 cycles, a specific capacity up to 1470 mAh g^?1 _sulfur (720 mAh g^?1 _cathode), and a high coulombic efficiency of over 99% even with a low amount of electrolyte are achieved. The alternative anodes do not suffer from electrolyte depletion, which is found to be the main cause of cell failure when using metallic lithium anodes.     

Planar defect of the nano-structured zinc oxide as the site for stabilization of the copper active species in Cu/ZnO catalysts

The catalytic activity of CuZn catalysts in the synthesis of methanol is related to those reduced Cu species, which originate from the Cu_xZn_1−xO solid solution of wurtzite-like structure. Copper cations in the Cu_xZn_1−xO solid solution are localized in the extended stacking faults of the ZnO lattice. Copper sites could be supposedly described as the product of introducing (OH)Cu(OH) to the planar defects of zinc oxide structure. Hydroxyl groups stabilize the planar defects of ZnO. The process of the samples reduction leads to the formation of flat Cu⁰ particles over the surface of zinc oxide. The planar defects of ZnO structure are preserved in the reduced state. During the reoxidation, copper atoms return back to the extended stacking faults of ZnO as the tape-like clusters of flat-square coordinated copper cations.     

Nutrition and physical activity program to attenuate obesity and promote physical and metabolic fitness in elementary school children

Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was approximately 16% less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con.     

Family influences on school achievement in low-income, African American children.

The authors examined the achievement-related beliefs and behaviors of parents of economically disadvantaged African American youth, and the relations among parental factors and children's academic self-concept and achievement. Forty-one children and their primary caregivers were interviewed. Parents reported on their academic-related beliefs and behaviors. Children completed measures of academic self-concept and 2 standardized achievement tests: 1 during the summer and 1 at the end of the following school year. Significant and positive relations were found between parental belief and behavior measures within the domains of reading and math; however, parental beliefs were more strongly linked with child outcomes than were parents' achievement-oriented behaviors. The relation between parental beliefs and child outcomes was not mediated by children's academic self-concept. Results are discussed in light of models of family influences on achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genetic Associations of Alcohol Dehydrogenase With Alcohol Use Disorders and Endophenotypes in White College Students.

Associations of alcohol dehydrogenase (ADH) gene polymorphisms (ADH1B*2 and ADH1C*1) with a lifetime alcohol use disorder (AUD) were examined in White college students. Alcohol-related endophenotypes likely to be influenced by elevations in acetaldehyde were also assessed. Individuals with an ADH1B*2 allele had lower rates of AUDs, consumed a lower maximum number of drinks in a 24-hr period, reported a greater level of response to alcohol, were more likely to have experienced alcohol-induced headaches following 1 or 2 drinks, and reported more severe hangovers than those lacking this allele. These findings are consistent with the hypothesis that enhanced sensitivity to alcohol and lower levels of alcohol use reflect the mechanism by which ADH1B*2 protects against developing an AUD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)