Comparative study of disk diffusion and microdilution methods for evaluation of antifungal activity of natural compounds against medical yeasts Candida spp and Cryptococcus sp

Antifungal activity of natural products has been tested by adapting methods designed for synthetic drugs. In this study, two methods for the determination of antifungal activity of natural products, agar diffusion and broth microdilution, the CLSI reference methods for synthetic drugs, are compared and discussed. The microdilution method was more sensitive. The minimal inhibitory concentrations (MIC) of crude extracts, fractions and pure substances from different species of the plant families Piperaceae, Rubiaceae, Clusiaceae, Fabaceae and Lauraceae, from the Biota project, were determined. Antifungal activities against Candida albicans, C.krusei, C.parapsilosis and Cryptococcus neoformans were produced by several samples.

Preparação e caracterização inicial de complexo de inclusão entre nitrofurazona e 2-hidroxipropil-β-ciclodextrina

Nitrofurazone (NF), 5-nitro-2-furaldehyde semicarbazone, a broad-spectrum antibiotic, has reported toxic effects and low solubility in water. It would be of great interest to form inclusion complexes between NF and a cyclodextrin, to develop more effective and safer antibiotic formulations. This paper focuses on the preparation of inclusion complexes of NF with 2-hydroxypropyl-β- cyclodextrin (HP-β-CD) and their initial characterization by evaluating rates of complex formation, photostability, solubility isotherms, release rate profiles, stoichiometry of the complexes and their morphology, as revealed by scanning electron microscopy. The kinetic tests of complex formation revealed that 17,3 h is enough for stabilization of the NF-cyclodextrin complex. The solubility isotherm studies showed that the isotherm changes from type A to type B, as a function of temperature. The photostability experiments showed that the insertion of the NF in the HP-β-CD cavity protects the drug from photodecomposition. The release kinetic tests showed that the profile of NF release from the complex is altered by the presence of HP-β-CD in the medium. A Job's plot indicated that the stoichiometry of the complex was 1:1 NF:HP-β-CD. The scanning electron micrographs showed changes in the crystal structure of NF in the complex. This study focused on the physicochemical properties of drug-delivery formulations that could potentially be developed into a novel type of therapy with NF.

Potencialização do efeito antiinflamatório e antinociceptivo do diclofenaco e da nimesulida por vitaminas do complexo B

The effects of a combination of some B vitamins and diclofenac or nimesulide on chemical nociception in mice or paw edema in rats were investigated. While the vitamins alone had no effect, combination of thiamine (B1), pyridoxine (B6) and cyanocobalamin (B12), given i.p. in doses of 100mg and 5mg/kg, respectively, potentiated the inhibition by nimesulide (5mg/kg) of paw edema induced by carrageenin in rats. Antinociceptive effects of diclofenac and nimesulide (inhibition of abdominal writhing induced by acetic acid in mice) were also potentiated by the combination of the vitamins B1, B6 and B12. Thiamine, pyridoxine and cyanocobalamin given singly were effective in potentiating antinociceptive effects of nimesulide, but only cyanocobalamin potentiated these effects of diclofenac, probably reflecting the differing mechanisms of action of the two drugs. The results document the positive influence of B vitamins on the antinociceptive effects of diclofenac or nimesulide and support the use of B vitamins to shorten the treatment time and reduce the daily dose of anti-inflammatories.

Detecção da produção de slime por estafilococos coagulase-negativa isolados de cateter venoso central

Slime production is an important virulence factor of coagulase-negative Staphylococcus spp., allowing them to attach to smooth surfaces of biomaterials, and it has been associated with infections of implanted medical devices. In the present study the production of slime capsules in 27 strains of coagulase-negative Staphylococcus was investigated by culture in Congo Red agar (77.7% positivity), spectrophotometric or microplate method (81.4% positivity) and scanning electron microscopy (88.9% positivity). The resistance of coagulase-negative strains of Staphylococcus to various antimicrobial agents was also determined by agar disk diffusion. The proportion of strains resistant to penicillin G, oxacillin, erythromycin, clindamycin and gentamicin among the slime-producing staphylococci was 88.9%, 70.4%, 81.5%, 66.7% and 59.2%, respectively; all of the coagulase-negative staphylococci were susceptible to vancomycin. The strains isolated from central venous catheters were identified by a conventional method and the API Staph system. The 27 coagulase-negative Staphylococcus strains were identified as: S. saprophyticus (3.7%), S. xylosus (7.4%), S. haemolyticus (14.8%), S. epidermidis (37.0%), S. warneri (14.8%), S. lugdunensis (7.4%), S. hominis (7.4%), S. schleiferi (3.7%) and S. chromogenes (3.7%). It can be concluded that in the most of the coagulase-negative Staphylococcus species there was an association between slime production, the nosocomial origin of the strains and reduced sensitivity to the antibiotics, suggesting a pathogenic potential in the hospital environment.

Influência das propriedades de granulados de lactose nas características físicas dos comprimidos

The compaction behavior of powdered solids used in tablets can be dominated by the physical-chemical properties of the excipients because, frequently, they are present in much larger amounts than the drug in tablet formulation. The aim of this study was to evaluate the influence of the size of lactose granules on the physical characteristics of tablets produced in punches of various diameters, since this relation has not been explored in the literature. Granules were produced in several sizes by wet granulation and compressed in punches of different diameters by applying different forces. Size distribution, apparent density and flow of granules were evaluated, as well as the physical characteristics of the tablets (weight, friability, hardness and disintegration time). The results indicate that in situations where excipient characteristics predominate due to low drug content, as in the 7 mm punch, the selection of granule size is important for the mechanical strength of tablet. On the other hand, with the 9, 11 and 13mm punches, it was possible to produce strong tablet from all sizes of granules.

Fatores de risco para doenças cardiovasculares em idosos com diabetes mellitus tipo 2

The aim of this study was to analyze the risk factors related to the cardiovascular diseases (CVRF) in elderly type 2 diabetics. A cross-sectional observational study was carried out on 100 elderly patients attending the Rehabilitation Center of Araraquara (CRRA), São Paulo State, Brazil, from March to December, 2004. The majority were married, female, white, with a low income and low educational level. Regarding habits and style of life, the subjects had an adequate diet, were sedentary, non-smoking and non-drinking. In the population of 100, 42% were overweight, 42% obese, 71% had above-normal waist measurements and 84% high waist-to-hip ratios. Concerning the CVRF, it was observed that more than half had hypertension, hypercholesterolaemia and hypertriglyceridaemia. 84% had high values of LDL-cholesterol and 59% HDL-cholesterol levels below the reference values, 78% high levels of fasting glycemia, 76% glycohemoglobin and 57% fibrinogen and thus subject to cardiovascular risk. The results showed a high frequency of cardiovascular risk factors, differing according to sex and the age.

Síntese e atividade biológica do derivado 6-formil-oxamniquina

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 MnO 2, applying CH 2Cl 2 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®).

Panoramic view of the occurrence of Yersinia species other than Y. pestis in Brazil

Data on the occurrence of Yersinia species, other than Y. pestis in Brazil are presented. Over the past 40 years, 767 Yersinia strains have been identified and typed by the National Reference Center on Yersinia spp. other than Y. pestis, using the classical biochemical tests for species characterization. The strains were further classified into biotypes, serotypes and phagetypes when pertinent. These tests led to the identification of Yersinia cultures belonging to the species Y. enterocolitica, Y. pseudotuberculosis, Y. intermedia, Y. frederiksenii and Y. kristensenii. Six isolates could not be classified in any of the known Yersinia species and for this reason were defined as Non-typable (NT). The bio-sero-phagetypes of these strains were diverse. The following species of Yersinia were not identified among the Brazilian strains by the classical phenotypic or biochemical tests: Y. aldovae, Y. rhodei, Y. mollaretti, Y. bercovieri and Y. ruckeri. The Yersinia strains were isolated from clinical material taken from sick and/or healthy humans and animals, from various types of food and from the environment, by investigators of various Institutions localized in different cities and regions of Brazil.

Caracterização de biotérios, legislação e padrões de biossegurança

The use of laboratory animals in conjunction with research on the human organism provides a basis for on understanding of several important physiological and pathological processes. Besides, the results of experimental studies enable technical and safety improvements to be made in surgical techniques used in the medical clinic. As living biological material is involved, we should guarantee its physical well-being, taking into account microbiological contamination and the genetics, nutrition and correct manipulation of the animals, in order to avoid incorrect conclusions from the experiments or unnecessarily large numbers of animals being used. In parallel with the concerns and legislation on the use of laboratory animals, there is also a growing preoccupation with the welfare and safety of those who handle the laboratory animals, since they run the risk of acquiring occupational diseases through contact with zoonotic pathogens or developing allergies. Prevention requires the application of modern technological advances in the design of the animal house and in the work routines. Unfortunately, few establishments in Brazil possess staff with adequate training and a basic infrastructure of research that includes the laboratory animal breeding centers, equivalent to those existing ones in the United States and Europe.

Influência das propriedades de granulados de celulose nas características físicas dos comprimidos

The compaction behavior of powdered solids can be strongly influenced by the physicochemical properties of excipients because they are frequently present in the tablet in larger amounts than the drug itself. The aim of this study was to assess the influence of the granule size of the cellulose on the physical characteristics of tablets produced in punches of different diameters, since this relation has never been explored in the literature. Granules of several sizes were produced by wet granulation and compressed in punches of various diameters by applying different forces. Size distribution, apparent density and flow of granules were assessed, as well as physical characteristics of the tablets (weight, hardness, friability and disintegration time). Reducing the granule size resulted in tablets of adequate crushing strength and fast disintegration; moreover, it allowed tablets to be produced without the need to use forces near the upper limit of the press, thus avoiding premature wear on the tabletting machine. Thus, once a suitable size for a given tablet formulation has been chosen, the granule size selected has been shown to determine the crushing strength of the tablet.

Análise da prescrição de medicamentos de pacientes hipertensos atendidos pelo SUS da rede municipal de saúde de Rincão - SP

The purpose of this study was to identify the drugs most often prescribed for hypertension at the Municipal Health Care Center of the town of Rincäo, State of São Paulo, Brazil, and the principal interactions arising from their association with other drugs, both anti-hypertensives and those in other classes. The study included 725 hypertensive patients registered at this health care center who were regularly seen by a physician every three months. Data were collected on age, sex, occurrence of diabetes, smoking, sedentary lifestyle and overweight, to obtain a profile of the hypertensive population of the area. Control records of all patients were available at the pharmacy in the health care center, where patients obtained their drugs once a month. Of the 725 patients, 38% were male and 62% female. Most (57%) were between 50 and 70 years of age, 21% used tobacco and 43% led a sedentary lifestyle. Single-drug therapy accounted for 33% of the prescriptions, multidrug therapy for 66%. In addition to anti-hypertensives, 50% of the patients took drugs of other therapeutic classes. Of those receiving multidrug therapy, 34% used three or more anti-hypertensives and 66% used only two of these drugs. Drug interactions were detected in as many as 47% of the prescriptions. Captopril was the drug that showed most interactions with others (54%), followed by hydrochlorothiazide (27%), furosemide (14%), propanolol (4%), and nifedipine (1%). The analysis revealed that drug consumption by the patients investigated is high, with a concomitantly high number of episodes of drug interaction.

Fatores relacionados à adesão das drogarias e farmácias de Tatuí-SP no projeto Farmácias Notificadoras

Pharmacovigilance is accomplished by voluntary notification of suspected adverse reactions, medication errors, and deviations from quality, by users and health professionals, through the filling in of forms that are sent to a data bank. To broaden the sources of notifications, the National Health Surveillance Agency (ANVISA), in partnership with the Regional Pharmacy Council (CRF) and Center for Health Surveillance (CVS) of each state, introduced the scheme of Notifying Pharmacies. The present study was aimed at determining the factors influencing the decision of drugstores and private pharmacies in Tatuí/SP in 2007, to join this project A descriptive, observational survey of knowledge, attitude and practice (KAP) was applied to volunteer pharmacists in the town. The results showed that the professionals are awave of pharmacovigilance, (95.24%) and have attitude (95.24%). However, practice is limited (6.0%). Based on this information we concluded that the low support of the project was due to lack of time, interest and no information about the benefits to society of such activity and a lack of support from the pharmacists' organizations. This situation is expected to change with the current introduction of a professional profile, the fusion of professional bodies and the promotion of social awareness on pharmacovigilance.

Determinação de cetamina em plasma por HPLC: Aplicação em um estudo de farmacocinética de associação medicamentosa em cães

A S(+) cetamina é um fármaco amplamente utilizado na medicina para induzir anestesia e a associação com midazolam é empregada para minimizar seus efeitos adversos. Associações medicamentosas podem resultar em interações farmacocinéticas e a disponibilidade de métodos bioanalíticos para a determinação da cetamina em plasma constitui ferramenta útil para a avaliação do perfil cinético do fármaco administrado isoladamente ou em associação. O presente estudo teve como objetivo o desenvolvimento e validação de um método analítico para determinação da cetamina em plasma por cromatografia líquida de alta eficiência (HPLC) e a investigação do perfil farmacocinético da cetamina em quatro cães hígidos da raça Beagle. A S(+) cetamina (10mg/kg) foi administrada pela veia cefálica em dose única isoladamente (protocolo I) ou associada ao midazolam (0.2mg/kg) (protocolo II) em estudo cruzado com intervalo de uma semana para washout. Amostras seriadas de sangue foram coletadas no intervalo de oito horas e analisadas por HPLC para a avaliação do perfil farmacocinético utilizando modelo bicompartimental. O método bioanalítico apresentou limites de confiança aceitáveis para sua aplicação em estudos de farmacocinética e os parâmetros área sob a curva (ASC0-8), volume de distribuição (Vd), clearance total (Clt), meia vida de eliminação (t/12 ß), constante de eliminação (ß), meia vida de distribuição (t1/2α) e constante de distribuição (α) não mostraram diferenças estatísticas significativas entre os grupos (p < 0.05, Wilcoxon). Os resultados obtidos sugerem que a redução dos efeitos colaterais da cetamina decorrente do uso da associação cetamina-midazolam não está relacionada a alterações no perfil farmacocinético da cetamina.

Determination of calcium and magnesium in hydroethanolic extracts of propolis by atomic absorption flame spectrophotometry

Propolis is a natural product collected by honeybees and has a large range of pharmacological activity, including antimicrobial, antitumoral, antioxidant and anti-inflammatory. Its use as a popular medicine is increasing all over the world, creating a need for quality control of the commercial products. In this study the levels of calcium and magnesium in commercial hydroalcoholic propolis extracts from varies states of Brazil were determined by atomic absorption flame spectrophotometry and different values were obtained for northern and southern states. This study can be extended to the analysis of metals that are harmful to health. The results showed that the calibration curves were linear over a wide concentration range (0.5-4.0 μg.mL -1 for calcium and 0.05-0.4 μg.mL -1 for magnesium) with good correlation coefficients (0.999 and 0.988, respectively). Good analytical recovery (94%) was obtained. The proposed method showed adequate precision and relative standard deviation lower than 2 %. The method is accurate and precise as well as having advantages such as simplicity and speed.

Protocolo para ensaios físico-químicos de estabilidade de fitocosméticos

The growing demand for stable, safe and effective cosmetics has required increasingly complex studies by the scientific community and the use of more efficient techniques to determine the stability of these products. The use of active principles from the Brazilian flora has led to the development of numerous products, in the most varied pharmaceutical forms, making it, even more difficult to standardize experimental protocols to certify the stability of cosmetic preparations. While in Brazil there is no one protocol that standardizes the tests that should be carried out to determine product stability, several studies have been conducted in academic laboratories to determine the stability of specific raw materials. The rheological properties of topical use products have to be taken into account in their manufacture, storage and application. The determination of the rheological behavior of a formulation helps in evaluating the physicochemical nature of the vehicle, allowing early signs of physical instability to be detected and thus enabling quality control of the constituents, test formulations and final products. Thermal analysis has also been used to assist in the study of cosmetic stability and differential scanning calorimetry to guide the development of new products. Other tools, such as fluorimetry and laser granulometry can be used to help the study and development of both emulsified and non-emulsified systems. The aim of the present study is to develop a protocol for the investigation of the physical and chemical stability of phytocosmetics - systems containing active compounds extracted from the Brazilian biodiversity.