Revista Brasileira de Ciências Farmacêuticas
A origem da Revista Brasileira de Ciências Farmacêuticas / Brazilian Journal of Pharmaceutical Sciences remonta aos “Anais de Farmácia e Odontologia da USP”, periódico iniciado em 1939. Em 1963, com o vol.1, teve início a “Revista da Faculdade de Farmácia e Bioquímica da Universidade de São Paulo”, que, em 1970, recebeu o título de “Revista de Farmácia e Bioquímica da Universidade de São Paulo”. Em 1999, foi totalmente reformulada, recebendo a denominação de Revista Brasileira de Ciências Farmacêuticas/Brazilian Journal of Pharmaceutical Sciences. OBS.: O revista mudou de título em 2009 para Brazilian Journal of Pharmaceutical Sciences
Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Antioxidant properties in cashew apple byproduct (Anacardium occidentale L.): effect on lipoperoxidation and on the polyunsaturated fatty acids profile in rats
The cashew apple (Anacardium occidentale L.) contains phenolic compounds usually related with antioxidant properties. Then, the aim of this study was to investigate its antioxidant capacity. The antioxidant capacity of the hydroalcoholic extract of the cashew apple pulp (EHAlc.) was assessed for the scavenging of the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) by in vitro method and by an in vivo essay. For this essay a 30-day oral (gavage, EHAlc. 200 and 400 mg/kg) study was conducted in Wistar male rats, evaluating hepatic, plasma and brain tissues. In DPPH model, the extract demonstrated antioxidant activity of 95 % (largest concentration, 1000 µg/ mL). There were found no relevant peroxidation comparing the treated animals with the control group. However, the treated group presented a lower level of brain lipoperoxidation. Also in the treated animals brain tissue was found the largest amount of polyunsaturated fatty acids (PUFA), mainly docosahexaenoic (DHA). Therefore, the analyzed extract from cashew apple pulp clone CCP-76 contains effective natural antioxidants, responsible for free radical scavenging in vitro and also for decreasing the brain lipoperoxidation and keeping the PUFAS levels in Wistar rats.
A investigação qualitativa em Farmácia: aplicação em Atenção Farmacêutica
O estado da arte da metodologia de investigação qualitativa no campo das Ciências Farmacêuticas é apresentado neste artigo, dando ênfase especial à área da Atenção Farmacêutica. Apresentamos os pressupostos teóricos e as investigações qualitativas mais importantes realizadas na área das ciências da saúde e no setor farmacêutico internacional. A partir da informação exposta, observamos que apesar do uso considerável dos métodos de investigação qualitativa no ambiente sanitário, sua aplicação no campo da Farmácia Assistencial e da Atenção Farmacêutica é ainda insuficiente, o que parece transcender para a América Latina, na qual o exercício desta nova filosofia de prática profissional ainda não se apresenta como atividade amplamente estabelecida. A avaliação do estado da profissão farmacêutica sob perspectiva social, a partir da percepção de pacientes, farmacêuticos e outros profissionais sanitários, assim como compreensão mais aprofundada dos principais desafios para a implementação da Atenção Farmacêutica, do ponto de vista qualitativo, podem contribuir fortemente para o avanço das atividades farmacêuticas clínicas, e, conseqüentemente, para o uso mais racional dos medicamentos para qualidade de vida dos pacientes.
Ciências Farmacêuticas^i2^spesquisa qualitat
Evaluation of the production of nitric oxide in mice, submitted to aerobic and anaerobic exercises
Nitric Oxide (NO) exerts important influences in several physiological processes. In this work we evaluated the production of sanguine NO in Wistar rats, submitted to the acute aerobic and anaerobic exercises. The formation of nitric oxide was verified through the dosage of the end products of oxidation of the metabolism of nitric oxide (nitrates). For this we used the colorimetric Griess method. We verified the existence of a significant difference (p = 0.000261) in the production of NO among the accomplishment of the aerobic swimming and the anaerobic, where the aerobic was shown more efficient in the promotion of higher levels. The acute aerobic exercise with duration of at least 10 minutes was shown more effective in the requirement production of NO in relation to the 5 minutes exercise. The positive relationship observed between the aerobic exercise and the formation of NO can help to explain the beneficial effects of the exercise in the cardiovascular health. We know that the practice of aerobic exercise and your duration increases the biodisponibility of NO, which is an important physiologic regulator of the blood pressure.
Vanessa Guimarães de Freitas Cruvelo D'Ávila
Synthesis and biological activity of 6-formyl-oxamniquine derivative
Schistosomiasis, an important disease in Brazil, is caused by a trematode of the genus Schistosoma, reaching millions of person in one of the most endemic region of this disease in the whole globe. The main goal of this work was to syntetize the 6-formyl-oxamniquine derivative and evaluate its biological activity. The 6-formyl-oxamniquine derivative was obtained by the oxidation of oxamniquine with MnO2, applying CH2Cl2 as solvent at room temperature for 24 hours. The obtaintion of 6-formyl-oxamniquine derivative compound was confirmed by IR spectroscopy and 13C NMR and ¹H NMR, presenting similar activity when compared to the commercial oxamniquine (Mansil®).
Importance of regulatory cytokine gene polymorphisms in hematopoietic stem cell transplantation
HLA genetic matching of donor and recipient is an important requirement for optimizing outcome following hematopoietic stem cell transplantation (HSCT). However, other non-HLA genes are being investigated for their role in graft-versus-host disease incidence and severity and in survival, by modulating the intensity of inflammation and tissue injury. These non-HLA-encoded genes include cytokine genes with polymorphisms within the 5' or 3' regulatory sequences of the genes. The polymorphisms or microsatellites may alter the transcription factor binding sites within the gene promoters and the amount of cytokine produced. This chapter summarizes the potential role of these genetic polymorphisms regarding the cytokines in predicting outcome of HSCT.
Hematopoietic stem cell^i2^stransplantat
Pharmaceutical care in the context of the family health strategy
The main objective of pharmaceutical policy management within the scope of SUS (Brazilian National Health System) is to guarantee the supply of drugs to local health centers, therefore displacing patient care When drug-related problems (DRP) and difficulties in adhering to the prescribed treatment are identified during the development of pharmaceutical follow-up, family and social issues have been shown to be reasons for unsuccessful treatment. They are key points to be considered during Pharmaceutical Care. The methodology chosen for this study was the pharmaceutical care of four patients monitored in a Health Unit in the city of Florianópolis. To solve drug related problems an approach was adopted that included family and social contexts using tools such as genogramming, ecomapping and interdisciplinary work. Family and support groups were shown to be important in addressing DRPs and there appears to be a need for the pharmacist to improve Pharmaceutical Care Practice by using these tools. The importance of home visits to gain a better understanding of the family environment was also observed, as well as the necessity of interdisciplinary work to improve the quality of care.
Antiamnesic evaluation of C. phlomidis Linn. bark extract in mice
Clerodendron phlomidis Linn. (Verbenaceae) is known as Agnimantha in sanskrit. Bark of the plant is used in treating various nervous disorders. In the present study C. phlomidis was investigated for its potential as a nootropic agent in mice. The aqueous extract of the C. phlomidis (100 and 200 mg/kg, p.o.) was administered for 6 successive days to both young and aged mice. Exteroceptive behavioral models such as elevated plus maze and passive avoidance paradigm were employed to evaluate short term and long term memory respectively. Scopolamine (0.4 mg/kg, i.p.), diazepam (1 mg/kg, i.p.) were employed to induce amnesia in mice. To delineate the mechanism by which C. phlomidis exerts nootropic action, its effect on brain acetyl cholinesterase levels were determined. Piracetam (200 mg/kg, i.p.) was used as a standard nootropic agent. Pretreatment with C. phlomidis (100 and 200 mg/kg, p.o.) for 6 successive days significantly improved learning and memory in mice. It reversed the amnesia induced by scopolamine, diazepam and natural ageing. It also decreased the acetyl cholinesterase levels in the whole brain. The bark of C. phlomidis can be of enormous use in the management of treatment of cognitive disorders such as amnesia and Alzheimer's disease.
Antinociceptive activity and toxicological study of aqueous extract of Egletes viscosa Less (Asteraceae)
Egletes viscosa Less (Asteraceae), popularly known as "macela" or "macela-da-terra", is a plant widely used in popular medicine due to its anti-inflammatory, bactericidal, antidiarrhoea, mio-relaxant, antispasmodic, antinociceptive, digestive, and anti-viral properties. Phytochemical screening of aqueous extract of Egletes viscosa (AEEV) revealed the high presence of flavonoids. This study examined the oral antinociceptive potential of AEEV in rodents using different concentrations (100, 200, and 400 mg/kg, p.o.). The results showed significant antinociceptive action when tested in writhing (200 and 400 mg/kg-p<0.05) and in the second phase of formalin tests (200 mg/kg-p<0.01 and 400 mg/kg-p<0.001). The inhibition (%) of extract in the writhing test was 63.4, 56.7, and 79.2% respectively for 200, 400, and acetyl salicylic acid (300 mg/kg); for the formalin test (second phase) results were 66.1, 84.7, and 96.2% respectively for 200, 400, and acetyl salicylic acid (300 mg/kg). Collectively, these observations suggest that AEEV is effective against continuous inflammatory pain. AEEV was well tolerated. In an acute toxicity test, oral administration of 5 g/kg of AEEV was performed and no mortality rate was observed. Similarly, in a subchronic toxicity study, no mortality was observed after 30 days of daily oral administration of 100 mg/kg of AEEV. There was no significant difference in the body and organ weights between control and experimental animals in both acute and subchronic toxicity tests. Pathological assays did not reveal any evidence of detectable differences in the gross appearance, as well as in the architectural or cellular pattern characteristics of the internal organs of the animals in both acute and subchronic tests. Nevertheless, significant differences were verified between males of the experimental and control groups regarding the levels of hemoglobin and leukocytes. In conclusion, AEEV did not induce any hazardous effects on the majority of the parameters studied. Additionally, an antinociceptive activity of the extract was verified. However, the increase in the levels of hemoglobin and leukocytes should be investigated in more detail.
Faecal fat excretion of mice (Rattus norvegicus, Wistar), submitted to hypercholesterolemic and hyperlipidic diets supplemented with chitosan
The effect of two comercial brands of chitosan in the faecal fat excretion was investigated in mice submitted to hypercholesterolemic and hyperlipidic diets. 32 rats Wistar, recently weaned, distributed randomly in four groups (n=8): control group (CG), received diet of AIN93G; hyperlipidic group (HG): diet of AIN-93G modified in the lipids content (12%) and supplemented with cholesterol (1%); and the chitosan hyperlipidic groups 1 (QHG1) and chitosan hyperlipidic 2 (QHG2), that received the same diet of the HG, supplemented with their respective chitosan (5%). The faecal collection was conducted on the days 0, 14th and 28th of the experiment. The faecal fat determination (g) was conducted through the Soxhlet method. No significant statistical differences (p>;0.05) were observed among the 4 groups as to the fat content in the beginning of the experiment. On the 14th day, the GHQ1 group had a significant increase of faecal fat when compared to the other three groups (p<0.05). On the 28th day, in the GHQ1 group, the faecal fat excretion was larger than in the other groups (p<0.05), while the group GHQ2 had not statistically differed from the group GH. The results suggest that the differences between these two groups can be caused by the purity degree, viscosity and deacetylation degree of the chitosans.
Dietetic supplements^i2^sexperimental st
Hypercholesterolemic diets^i2^sexperimental st
Hypercholesterolemia^i2^sexperimental st
Pharmaceutical intervention and prevention of drug related problems
In the present study, we describe the pharmaceutical interventions performed by the pharmacy service of a public orthopaedic hospital at Rio de Janeiro, Brazil. In a retrospective study, we analysed the pharmaceutical interventions performed during a year (from june 2004 to june 2005). The pharmacy service assisted 13.6% of the 5476 patients that were submitted to internation. In 30.4 % of the patients that were directly assisted by the pharmacist was identified the necessity of pharmaceutical interventions, reaching 227 interventions during the period of the study. The physicians were the most requested professionals (71.1%), followed by nurses 16.9%. Eighty four percent of the problems that were detected were related to potential medication errors. Forty nine percent of these errors were prevented by the pharmacists. It was possible to predict some of the potential drug related problems that could be related to these patients as well. Seventy percent of the pharmaceutical interventions were accepted by the professionals. For the interventions related to prescription, sixty percent were accepted. The results suggest that pharmaceutical interventions were effective to prevent drug adverse events, reinforcing the important role of pharmacists in hospital assistance.
Validation of spectrophotometric methodology for quantify flavonoid content in Bauhinia cheilantha (Bongard) Steudel
Phytotherapeutic laboratories require access to methodologies that guarantee quality control for their products when these items are not already registered in pharmacopeias or official monographs. As such, the present study sought to validate analytical methodologies for quantifying natural flavonoids contained in extracts of "pata-de-vaca" (Bauhinia cheilantha [Bong.] Steudel) using visible light spectrophotometry and a rutin standard (µg/ml). All of the parameters required by ANVISA were evaluated. The specificity test revealed a maximum absorption peak at 420 nm. The methodology was considered linear and of high quantification sensitivity (2.51 µg/ml). The methodology also proved to be robust, and had high recovery levels (98.36%). The results obtained for repeatability, intermediate precision (intra- and inter-day), and reproducibility all certified the precision of the method, with values between 0.31 and 3.58%; the methodology was also considered exact (95.71-105.50%). This study demonstrated that the proposed methodology can be considered specific, precise, reproducible, exact, of low cost, and easy to perform.
Study utilization of parenteral medications in pediatric unit of universitary hospital
Parenteral drug administration has clinical relevance in pediatric care and the risk of acquire nosocomial infection. The purpose of this observational cross-sectional study was to describe the utilization of parenteral drugs in a pediatric unit. A research questionnaire was created. The variables about pharmacotherapy were collect in prescriptions. The descriptive statistical analysis was performed using SPSS A total of 75 patients were admitted, 56% were male. The age range most frequently was the infants. The length of hospitalization was over 20 days (24.0%), 6 to 10 days (21.3%) and less than 3 days (17.3%). Parenteral route was used to 56 (74.7%) patients, so 19 (25.3%) used other routes or did not use medicine. Intravenous route was used to 52 (92.9%) patients. Overall, 47 different parenteral drugs were prescribed . The average of 4 drugs per patient requires more time of nursing team in activities related with drug administration. The high number of drug prescribed per patient raise concern about safety. The pharmacist should stimulate conversion from parenteral to oral administration .
Investigation of the antimycobacterial activity of 36 plant extracts from the brazilian Atlantic Forest
Thirty-six plant extracts from the brazilian Atlantic Forest were tested for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv and M. kansasii, using the method REMA in seriate concentrations of 100 to 0.20 µg/mL. Among the thirty six extracts tested, five were active against M. tuberculosis, and three of these extracts also showed activity against M. kansasii. Cytotoxicity test with VERO cells was performed with the five extracts active against M. tuberculosis. Only the extract of Peschiera affinis was identified as non-toxic in the concentration of 100µg/mL.
Plant extracts^i1^santimycobacterial activ
Effect of processing on nutritional value of the mandim fish (Arius spixii)
In an attempt to analyze how processing enhances the nutritional value of the mandim fish (Arius spixii) marketed in Maceió-AL, Brazil, the following nutritional components were determined in fresh and processed (salted-dried) fish: centesimal composition, calorie count, chloride, fatty acid and cholesterol profile. The presence of cholesterol oxides was also investigated. Respective results for fresh and processed mandim fish were: moisture (70.13% and 40.31%), proteins (51.73% and 38.07%, dried), carbohyrdrates (4.67% and 2.24%, dried), calories (486 kcal/100g and 367 kcal/100g, dried), fatty acids (polyunsaturared 14,54% and 15,49%, ômega-3 8,51% and 6,51%), cholesterol (82.66 mg/100g and 61.30 mg/100g) and oxides (7-ketocholesterol 8.31 µg/g and 17.90 µg/g). These figures clearly showed that processing led to significant change in the nutritional value of the mandim fish.
Cholesterol oxides^i2^sdetermination in f
Elizabeth Aparecida Ferraz da Silva Torres
Spectrophotometric determination of fenoterol hydrobromide in pharmaceutical preparations
A simple spectrophotometric method has been developed for the determination of fenoterol hydrobromide (FH) in tablets, drops and syrup, as the only active principle and associated with ibuprofen. The method is based on the oxidative coupling reaction of the FH with 3-methyl-2-benzothiazolinone hydrazone (MBTH) and ceric sulphate as oxidant reagent. The mixture of the drug, MBTH and ceric sulfate, in acid medium, produces a red brown color compound, with absorption maximum at 475 nm. The calibration curve was linear over a concentration range from 3.0 to 12.0 µg/mL, with correlation coefficient of 0.9998. The different experimental parameters affecting the development and stability of the color compound were carefully studied and optimized. The method was applied successfully to assay FH in dosage forms and simulated samples. The coefficient of variation was from 0.25 % to 0.82 % and average recoveries of the standard from 98 % to 102 %. The excipients (tablets and drops) did not interfere in the analysis and the results showed that method can be used for determination of the FH isolated or associated with ibuprofen with precision, accuracy and specificity. In case of syrup, the interference in the analysis suggests a possible reaction between vehicle components with MBTH.
Development and validation of an analytical method for Nystatin vaginal cream by high performance liquid chromatography
Nystatin is a polyenic antibiotic with fungistatic and fungicide characteristics that acts by de-structuring the cellular membrane of fungi and yeast. The nystatin vaginal cream is used for the treatment of vaginal candidiasis. Until recently, the official compendia professed the microbiological trial for dosing this antibiotic, method considered as non-feasible in the routine of quality control centers due to the excessive time for release of results. Aiming at obtaining an alternative method for dosing nystatin vaginal cream, a chromatographic method (HPLC) was developed and validated. The method developed used a reversible phase column of C18, 3.9 x 150 mm, 4 mm, at 30 ºC. The mobile phase was made up of a 0.25 mM sodium phosphate buffer and 0.025 mM EDTA, pH 6.00, methanol and acetonitrile (40:30:30), rate of 1.0 mL/minute and wavelength of 305 nm. The validated method showed to be accurate, precise, robust, linear and specific, in addition to being fast and practical, able to be used for analytic dosing of nystatin vaginal cream.
High Performance Liquid Chromatography^i2^smethod's validat
Medicinal plants used by the population assisted by the "Programa de Saúde da Família" (Family Health Program) in Governador Valadares County - MG, Brazil
This study was conducted to evaluate the use of medicinal plants by the population assisted by the "Programa de Saúde da Família" in Governador Valadares -MG, in order to rescue, preserve and use this knowledge in works carried out with the community. The preestablished questionnaire methodology was used. Those questionnaires were applied by the Family Health Agents. The study was accomplished in 27 residential quarters, as being applied 2454 questionnaires, and 232 plants were mentioned as medicinal ones by the interviewed population. The main indications for using the medicinal plants were: as sedative (10%), against influenza (18%) and infections (9%). Most plants under use are prepared as tea (78%) and are obtained in own cropping (57%). In general, the knowledge on the use and preparation of the medicinal plants proceeded from their relatives (67%). Most mentioned and popularly used species have pharmacological activity already proven in the literature. However, this population needs a correct orientation on their cropping and therapeutic use.
Validation of a UV-spectrophotometric analytical method for the determination of usnic acid in liposomes
The secondary lichen metabolite usnic acid [2,6-diacetyl-7,9-dihydroxy-8,9b-dimethyl-1,3(2H,9bH)-dibenzofuran] has demonstrated pharmacological potential activities such as antitumor, antimicrobial, antiviral, antiproliferative, and anti-inflammatory. Liposomes are vesicles composed of phospholipid bilayers surrounding aqueous compartments and they have been used as colloidal drug carriers. The aim of this study was to develop and validate a quantitative UV spectrophotometric method for determination of usnic acid in liposomal formulations. The validation parameters were assessed according to The International Conference on Harmonization (ICH) and American Pharmacopoeia guidelines. The linearity range was of 3-15 µg.mL-1, regression equation: absorbance = 0.070 x UA concentration (µg.mL-1) + 0.013, and r = 0.9997. The repeatability (relative standard deviation) of the method was 1.96% and intermediate precision indicated that the difference among mean was statistically insignificant (P < 0.05). The accuracy revealed a mean percentage recovery of 100.4% of usnic acid. The method was robust for the variation of temperature and solvent. The detection and quantization limits were found to be 0.34 and 1.13 µg.mL-1, respectively. The content of usnic acid in liposomes was of 96.8% (± 0.2). The proposed method is accurate, precise and reproducible for estimation of usnic acid as raw material and in pharmaceutical dosage forms such as liposomes.
Quantitative analysis^i2^smethod's validat
Diazepam, in a single dose, inhibits cellular chemotaxis, macrophage stimulation, and TNF-α activity in LPS-induced acute inflammatory responses in mice
Benzodiazepines are one of the most frequently prescribed drugs due to their anxiolytic properties. The aim of this study was to evaluate the effects of diazepam on lipopolysaccharide-induced peritoneal acute inflammatory responses. Swiss mice were treated with diazepam in a single dose of 1 or 10 mg/kg- subcutaneously 1 h before an intraperitoneal injection of lipopolysaccharide or sterile saline solution. The mice were killed 16 h after and the cells were washed from the peritoneal cavity to determine the total number of cells and the mononuclear and polimorfonuclear subpopulations, as well as the TNF-alpha activity and percentage of spread macrophages. Our results showed that the diazepam treatment (1 and 10 mg/kg) induced a significant reduction in the LPS-induced macrophage stimulation and TNF-α activity. Diazepam (10 mg/kg) also reduced the inflammatory cellular migration when compared to the control. It can be concluded that the diazepam treatment in a single dose is able to influence the inflammatory cellular influx, macrophage stimulation and TNF-α activity in the acute inflammatory response in mice, having possible implications on the anti-infectious response efficiency.
The evolution of pharmaceutical care and the prospect for the Brazil
The Pharmaceutical Care, recent practice of the pharmaceutical activity, prioritizes the orientation and the pharmacotherapeutic follow up, besides direct relation among the pharmacist and the medicine's user. In most developed countries the Pharmaceutical Care is already a reality and has demonstrated efficacy in the reduction of aggravation in the chronical diseases and in the cost of the health system. In Brazil, this activity is still incipient due to the difficulty of access to the medicines by the users of the Health System, absence of pharmacists in the Basic Units of Health and absence of scientific documentation that may demonstrate to the managers of the public and private system of Health that the implementation of Pharmaceutical Care represent investment and not cost. However, for being a new activity of the pharmacist, it is demanding that the pharmaceutical education institutions promote the necessary adaptations, providing the formal knowledge for the practice of this activity. This paper discuss the Pharmaceutical Care in countries that present more evolution in your desenvelopment according with MedLine/Pubmed (www.ncbi.nlm.nih.gov/PubMed). This article compared the difficulties of the Brazil and others countries for the implantation of Pharmaceutical Care and the prospect for the future.
The emergence and dissemination of antimicrobial resistance are problems of great importance worldwide, particularly between nosocomial pathogens of clinical importance such as nonfermentative Gram-negative bacilli and members of the family Enterobacteriaceae. The main mechanism of resistance these pathogens is the production of β-lactamases, which are enzymes that hydrolyzing the ring β-lactam hindering the action of antimicrobial β-lactam. The β- lactamases were classified into four classes of according its primary structure and may also be classified in two groups based on their catalytic mechanism, that is, serine-β-lactamases (Classes A, C and D) e metallo-β-lactamases (Class B). The metallo-β-lactamases (MβL) using ions divalentes, commonly zinc, as co-factor for its catalytic activity and currently represent one the most important class of enzymes, due of their ability to hydrolyze all antimicrobial β-lactam, including carbapenens, which are used in the treatment of Gram-negative bacteria multidrug-resistant and to remain stable before the serine-β-lactamases. The detection of samples producing of MβL helps infection control practioners to prevent the dissemination of this mechanism of resistance in the nosocomial environment and to prevent it come to the community, and emphasize the rational use of antimicrobial currently available for clinical use, since there are few investments in the pharmaceutical industry in search of new antimicrobial agents.
Current aspects of branched chain amino acid and exercise
In healthy humans, nine amino acids are considered to be essential once they cannot be endogenously synthesised and must therefore be ingested in the diet. Amongst the essential amino acids are the three branched chain amino acids, namely, leucine, valine and isoleucine. These amino acids participate in the regulation of protein balance in addition to being nitrogen sources for the synthesis of alanine and glutamine. As to the regulation of muscle protein synthesis, leucine acts in the stimulation of initiation of mRNA translation into protein, both through mechanisms that are dependent and independent of insulin. In the physiology of physical exercise, these branched amino acids play a role in central fatigue hypothesis, in muscle protein balance, in the secretion of insulin, in the modulation of the immune response, in performance enhancement of individuals who work out in hot environments, and in avoiding muscle lesion. This review approaches all aspects of the metabolism of and supplementation with branched chain amino acids in physical exercise.
Growth hormone and physical exercise: current considerations
Although growth hormone (GH) is one of the most extensively studied hormones, various aspects related to this hormone have not been completely established, including its relationship with physical exercise. Recent studies have contributed to the understanding of the mechanisms of action of GH, which can be divided into 1) direct actions mediated by intracellular signals that are triggered by the binding of GH to its receptor on the plasma membrane, and 2) indirect actions mediated mainly by the regulation of the synthesis of insulin-like growth factors (IGF). Physical exercise has been shown to be a potent stimulator of GH release, especially in young men and women. The magnitude of this increase is influenced by several factors, especially the intensity and volume of exercise, in addition to training status. In this respect, athletes normally present a lower exercise-induced GH release than sedentary or poorly trained individuals. Experimental evidence indicates that GH may 1) favor the mobilization of free fatty acids from adipose tissue for energy generation, 2) increase the capacity of fat oxidation, and 3) increase energy expenditure.
Mucoadhesion studies in the gastrointestinal tract to increase oral drug bioavailability
The oral bioavailability of many drugs can be limited by the residence time of pharmaceutical dosage forms in the gastrointestinal tract. Mucoadhesion has been proposed as a method to increase residence time at a specific area, hence increasing the therapeutic effect of drugs. Most research efforts on mucoadhesion have focused on the stomach and small intestine, with promising results observed from in in vitro studies. However, γ-scintigraphy data obtained in human studies have revealed the lack of success of mucoadhesion approaches in order to increase the contact time of formulations in the upper gut. The lack of in vitro/in vivo correlation can be attributed to the complex nature of the human gastrointestinal tract, with most in vitro models providing little resemblance to the in vivo situation, such as motility, pH, mucus thickness and mucus turnover, presence of enzymes and food. In the colon, the mucus turnover, the sensibility to mucus secretory stimulus and motility are lower than in the stomach and small intestine. Therefore, colonic mucoadhesion may be a more successful approach. Nevertheless, more studies in animals and humans are needed to evaluate its potential, as well as, pharmacokinetic studies to investigate drug release and absorption from mucoadhesive systems.
Mucoadhesion^i2^sin vitro and in vivo stud
Gastrointestinal tract^i2^smucoadhesion st
Biomarker methods in drug discovery and development
The nutritional biochemistry of chromium (III)
Structural proteomics: high-throughput methods