Early Aggregation of Amyloid-ß(1-42) Studied by Fluorescence Correlation Spectroscopy.

Alzheimer's disease (AD) is a progressive neurodegenerative disease affecting cognitive and memory abilities and is believed to be linked to the formation and accumulation of neurotoxic aggregates of the Amyloid-ß peptide (Aß). In particular, it is the formation of soluble pre-fibrillar oligomers within the early stage of Aß aggregation which is thought to represent a key step in the development of AD, thus underlining the interest in characterizing the aggregation process and the nature of these aggregates. In this context, fluorescence correlation spectroscopy (FCS) has emerged as a valuable alternative for the study of these systems in solution. Indeed, the use of FCS to study terminally labelled Aß provides a means to detect changes in the size and concentration of initially monomeric Aß samples by monitoring these fluorescently labelled species freely diffusing in solution with single-molecule resolution. Herein, we show how to employ FCS to study the early aggregation process of Aß(1-42) and how this can be used to estimate the critical concentration for oligomer formation and to characterize the aggregates formed.

Perfil epidemiológico e letalidade de pacientes com doença renal crônica em tratamento dialítico pelo SUS, no estado de São Paulo, no período de 2008 a 2017 / Epidemiological profile and lethality of patients with chronic kidney disease undergoing dialysis, treated at SUS, in the State of São Paulo, from 2008 to 2017

Introdução - A doença renal crônica (DRC) tem sido considerada um importante problema na saúde pública por ser uma doença silenciosa nos estágios iniciais e, no estágio avançado, apresentar complicações que demandam tratamento dialítico ou transplante renal, denominados de Terapia Renal Substitutiva (TRS). No Brasil, o sistema de informação ambulatorial recebe das instituições vinculadas ao Sistema Único de Saúde (SUS), por meio da Autorização de Procedimentos de Alta Complexidade/TRS (APAC/TRS), as informações dos pacientes em tratamento dialítico. Seus dados possibilitam conhecer o perfil epidemiológico desses pacientes. Objetivo - Descrever o perfil epidemiológico e letalidade dos pacientes com DRC, no estágio 5, em tratamento dialítico (DRC G5D) pelo SUS, no estado de São Paulo (ESP), no período de 2008 a 2017. Métodos - Trata-se de um estudo descritivo e retrospectivo, de abordagem quantitativa, que utiliza como base o banco da APAC/TRS. Os dados foram analisados para os 17 Departamentos Regionais de Saúde (DRS) do estado. Foi feita a série temporal dos casos prevalentes, casos novos e letalidade dos pacientes em tratamento dialítico no SUS, estratificados por sexo e faixa etária. As curvas de sobrevida foram estimadas pelo método de Kaplan Meyer e comparadas pelo teste de log-rank. A produção ofertada de diálise no SUS foi comparada com o parâmetro de cobertura assistencial estabelecido na Portaria ministerial 1631, de 2015. As causas dos óbitos foram retiradas do Sistema de Informações de Mortalidade. Resultados - No período observado foram realizados 275.778 procedimentos de diálise para 86.381 pacientes, sendo inseridos 70.615 casos novos e houve 30.784 óbitos. O perfil sociodemográfico geral mostrou um predomínio do sexo masculino, raça branca e média de idade dos pacientes em diálise de 56,5 anos, sendo a hemodiálise o procedimento principal em 92% dos casos. Os dados referentes às causas dos óbitos mostram em primeiro lugar a doença cardiovascular (20,1%) - sendo 10,5% correspondente à hipertensão e 9,6% ao infarto agudo do miocárdio, seguida de diabetes (18,1%), broncopneumonia (15,6%) e septicemia (13,8%). Na série temporal houve uma tendência crescente para casos prevalentes e níveis estacionários para casos novos e letalidade. A média geral de sobrevida dos pacientes em diálise foi de 75,9 meses. Em 2017, o ESP apresentou produção de diálise de 69/100.000 hab., menor que o parâmetro de cobertura assistencial, estimado em 75/100.000 hab., com heterogeneidade entre os DRS. No período analisado verificou-se uma ampliação de cerca de 10% de serviços de diálise para o SUS. Conclusão - Houve aumento de serviços de diálise e de casos prevalentes no ESP, embora a oferta de procedimentos de diálise tenha sido menor que o parâmetro de cobertura assistencial, estimado para a população. A análise dos dados da APAC, mesmo tendo como finalidade o pagamento dos procedimentos médico hospitalares, contribuiu para avaliar o perfil epidemiológico dos pacientes portadores de DRC G5D, no SUS, e identificar diferenças regionais de oferta de diálise, de pacientes dialisados e na sobrevida. Esses resultados podem orientar outras análises que permitam entender melhor essas desigualdades e subsidiar ações para minimizá-las.

Introduction - Chronic kidney disease (CKD) has been considered an important public health problem, for being a silent disease in the early stages and presenting complications in the advanced stage that will require dialysis i.e. Renal Replacement Therapy (TRS) or kidney transplantation. In Brazil, the outpatient information system, receives information from patients undergoing dialysis treatment from institutions linked to the Unified Health System (SUS), through the Authorization for High Complexity Procedures/TRS (APAC/TRS). Its data make it possible to know the epidemiological profile of these patients. Objective - Describe the epidemiological profile and lethality of patients with CKD, in stage 5, undergoing dialysis treatment (CKD G5D) at SUS, in the State of São Paulo (ESP), from 2008 to 2017.Methods - This is a descriptive and retrospective study, which applies a quantitative approach that uses the database of APAC/TRS. Data was analyzed for the State's 17 Regional Health Departments (DRS). A time series was made considering prevalent cases, new cases and the lethality of patients undergoing dialysis treatment at SUS, stratified by sex and age group. Survival curves were estimated using the Kaplan Meyer method and compared using the log-rank test. The offered production of dialysis in SUS was compared with the parameter of care coverage established in Ministerial Decree 1631, from 2015. The causes of death were removed from the Mortality Information System. Results - With regards to the observed period, 275.778 dialysis procedures were performed, on 86.381 patients, from which 70.615 were inserted as new cases, and 30.784 died. The general sociodemographic profile showed a predominance of male, white and average age of 56.5 years of patients on dialysis, with hemodialysis being the main procedure in 92% of the cases. Data related to causes of death show cardiovascular disease (22.1%) in the first place, with 10.5% corresponding to hypertension and 9.6% to acute myocardial infarction; followed by diabetes (18.1%), bronchopneumonia (15.6%) and septicemia (13.8%). In the assessed time series, there was an increasing trend for prevalent cases, but new cases and lethality remained at stationary levels. The overall average survival of patients on dialysis was 75.9 months. In 2017, the state presented a dialysis production rate of 69/100,000 hab., which was less than the parameter of assistance coverage, estimated at 75/100,000 hab., with heterogeneity between the DRS, and an increase of about 10% in the offer of dialysis services for SUS, in the analyzed period. Conclusion - There was an increase in dialysis services as well as prevalent cases in the State of São Paulo (ESP), although the number of dialysis procedures performed was less than the the parameter of assistance coverage for the population. The analysis of the APAC data, even though its main purpose is for paying for hospital medical procedures, contributed to the assessment of the epidemiological profile of patients with DRC G5D, treated at SUS, as well as to identify regional differences in the supply of dialysis, dialysis patients and survival rates. These results may guide other analyzes that would allow for a better understanding of these inequalities and subsidize actions to minimize them.

Critical aggregation concentration for the formation of early Amyloid-ß (1-42) oligomers.

The oligomers formed during the early steps of amyloid aggregation are thought to be responsible for the neurotoxic damage associated with Alzheimer's disease. It is therefore of great interest to characterize this early aggregation process and the aggregates formed, especially for the most significant peptide in amyloid fibrils, Amyloid-ß(1-42) (Aß42). For this purpose, we directly monitored the changes in size and concentration of initially monomeric Aß42 samples, using Fluorescence Correlation Spectroscopy. We found that Aß42 undergoes aggregation only when the amount of amyloid monomers exceeds the critical aggregation concentration (cac) of about 90 nM. This spontaneous, cooperative process resembles surfactants self-assembly and yields stable micelle-like oligomers whose size (≈50 monomers, R h ≈ 7-11 nm) and elongated shape are independent of incubation time and peptide concentration. These findings reveal essential features of in vitro amyloid aggregation, which may illuminate the complex in vivo process.

Antinociceptive and Anti-inflammatory Effects of Triterpenes from Pluchea quitoc DC. Aerial Parts.

BACKGROUND: Pluchea quitoc DC. (Asteraceae), a medicinal plant known as "quitoco," "caculucage," "tabacarana" and "madre-cravo," is indicated for inflammatory conditions such as bronchitis, arthritis, and inflammation in the uterus and digestive system. OBJECTIVE: This study evaluated the analgesic and anti-inflammatory activities of the triterpenes compounds obtained from P. quitoc aerial parts. MATERIALS AND METHODS: The triterpenes compounds ß-amyrin, taraxasterol and pseudo-taraxasterol in a mixture (T); ß-amyrin, taraxasterol and pseudo-taraxasterol acetates in a mixture (Ta); ß-amyrin, taraxasterol, pseudo-taraxasterol acetates in a mixture with ß-amyrin, taraxasterol and pseudo-taraxasterol myristates (Tafe) were analyzed in the models of nociception and inflammation. The evaluation of antinociceptive activity was carried out by the acetic acid-induced writhing and tail-flick tests while leukocyte migration to the peritoneal cavity was used for anti-inflammatory profile. RESULTS: The oral administration of T or Tafe (40 mg/kg and 70 mg/kg) and Ta (70 mg/kg) to mice reduced acetic acid-induced writhing. The tail-flick response of mice was not affected by T or Tafe (40 mg/kg). T or Tafe (40 mg/kg) and Ta (70 mg/kg) also inhibited peritoneal leukocyte infiltration following the injection of carrageenan. CONCLUSION: The results demonstrate the anti-inflammatory and peripheral antinociceptive activity of the triterpenes ß-amyrin, taraxasterol, and pseudo-taraxasterol that were decreased when these were acetylated; while the acetylated triterpenes in mixture with myristyloxy triterpenes improved this activity. These compounds seem, at least in part, to be related to the plant's reported activity. SUMMARY: The mixtures of hydroxylated, acetylated, and myristate triterpenes isolated from hexanic extracts of Pluchea quitoc DC. were analyzed in the models of nociception and inflammation in mice. The results demonstrate the anti-inflammatory and peripheral antinociceptive activity of the triterpenes ß-amyrin, taraxasterol, and pseudo-taraxasterol. This study showed too that the activity of triterpenes may be decreased by their being acetylated, while the acetylated triterpenes in mixture with myristate triterpenes improved this activity.Abbreviations Used: T: Triterpenes compounds ß-amyrin, taraxasterol, and pseudo-taraxasterol in a mixture, Ta: Triterpenes compounds ß-amyrin, taraxasterol and pseudo-taraxasterol acetates in a mixture, Tafe: Triterpenes compounds ß-amyrin, taraxasterol, pseudo-taraxasterol acetates in a mixture with ß-amyrin, taraxasterol and pseudo-taraxasterol myristates, Ctrl: Control, Indo: Indomethacin, Dexa: Dexamethasone, EtOAc: Ethyl acetate, MeOH: Methanol.

Towards ratiometric sensing of amyloid fibrils in vitro.

The aggregation of amyloid-ß peptide and its accumulation in the human brain has an important role in the etiology of Alzheimer's disease. Thioflavin T has been widely used as a fluorescent marker for these amyloid aggregates. Nevertheless, its complex photophysical behavior, with strong wavelength dependencies of all its fluorescence properties, requires searching for new fluorescent probes. The use of 2-(2'-hydroxyphenyl)imidazo[4,5-b]pyridine (HPIP), which shows two emission bands and a rich excited-state behavior due to the existence of excited-state intramolecular processes of proton transfer and charge transfer, is proposed. These properties result in a high sensitivity of HPIP fluorescence to its microenvironment and cause a large differential fluorescence enhancement of the two bands upon binding to aggregates of the amyloid-ß peptide. Based on this behavior, a very sensitive ratiometric method is established for the detection and quantification of amyloid fibrils, which can be combined with the monitoring of fluorescence anisotropy. The binding selectivity of HPIP is discussed on the basis of the apparent binding equilibrium constants of this probe to amyloid-ß (1-42) fibrils and to the nonfibrillar protein bovine serum albumin. Finally, an exhaustive comparison between HPIP and thioflavin T is presented to discuss the sensitivity and specificity of these probes to amyloid aggregates and the significant advantages of the HPIP dye for quantitative determinations.

Antihypertensive Effect of Syzygium cumini in Spontaneously Hypertensive Rats.

This study evaluated the in vivo potential antihypertensive effect of hydroalcoholic extract of Syzygium cumini leaves (HESC) in normotensive Wistar rats and in spontaneously hypertensive rats (SHR), as well as its in vitro effect on the vascular reactivity of resistance arteries. The hypotensive effect caused by intravenous infusion of HESC (0.01-4.0 mg/kg) in anesthetized Wistar rats was dose-dependent and was partially inhibited by pretreatment with atropine sulfate. SHR received HESC (0.5 g/kg/day), orally, for 8 weeks and mean arterial pressure, heart rate, and vascular reactivity were evaluated. Daily oral administration of HESC resulted in a time-dependent blood pressure reduction in SHR, with a maximum reduction of 62%. In the endothelium-deprived superior mesenteric arteries rings the treatment with HESC reduced by 40% the maximum effect (E max⁡) of contraction induced by NE. The contractile response to calcium and NE of endothelium-deprived mesenteric rings isolated from untreated SHR was reduced in a concentration-dependent manner by HESC (0.1, 0.25, and 0.5 mg/mL). This study demonstrated that Syzygium cumini reduces the blood pressure and heart rate of SHR and that this antihypertensive effect is probably due to the inhibition of arterial tone and extracellular calcium influx.

The toxicity evaluation of Syzygium cumini leaves in rodents

This study aimed to evaluate the safety of the hydroalcoholic extract (HE) of Syzygium cumini (L.) Skeels, Myrtaceae, leaves in rodents. Acute toxicity was evaluated through the determination of a LD50 in mice and rats (up to 14 days). In mice, the oral administration (p.o.) of the HE (0.1 at 6 g/kg) did not cause any death. When administered by intraperitoneal route (i.p.) the HE (0.1 at 1 g/kg) caused death of the animals (LD50 of 0.489 g/kg). In rats, the HE (0.5, 1 and 2 g/kg, p.o.) did not cause any death, while by i.p., only the 2 g/kg dose was lethal to 67 percent of the animals. To evaluate chronic toxicity, groups of rats daily received the HE (0.05, 0.1 and 0.25 g/kg) through p.o., during 30, 90 or 180 days and the effects on behavior, body weight, feed consumed were measured. Histology, hematology and biochemical parameters were measured at the end of the treatment. After a 30-day treatment, the HE caused changes in some biochemical parameters. Histological examination of the liver, kidneys, lungs, heart, stomach, intestine and pancreas showed normal architecture suggesting no morphological disturbances. These data may mean that the HE of S. cumini does not exert acute or chronic toxic effects by oral administration.

Antiulcerogenic activity of the extracts of Struthanthus marginatus

The gastroprotective action of the aqueous extract (AE) and the hydroalcoholic extract obtained from the leaves of Struthanthus marginatus (Desr.) Blume, Loranthaceae, were performed with in vivo models in rodents using: ethanol, indomethacin or stress-induced ulcers, determination of gastric secretion and the mucus production. The scavenger activity of AE in vitro was tested by the DPPH method. The treatment with the extracts (125-1000 mg/kg) significantly inhibited ulcerative lesions in comparison with the negative control groups in all the models evaluated and demonstrated greater effectiveness of the aqueous extract. Regarding the model of gastric secretion, a reduction in volume of gastric juice and total acidity was observed, as well as an increase in the gastric pH. The treatment of rats raised the gastric mucus production. Significant DPPH scavenging activity was evident in the AE. No sign of toxicity was observed. These results show that S. marginatus possesses gastroprotective activity. There are indications that the mechanisms involved in anti-ulcer activity are related to a decrease in acid secretion and an increase in gastric mucus content. Also, there is evidence for the involvement of antioxidant activity in the gastroprotective mechanism.

Antispasmodic effect of Jatropha gossypiifolia is mediated through dual blockade of muscarinic receptors and Ca2+ channels

The antispasmodic activity of Jatropha gossypiifolia L., Euphorbiaceae, aerial parts was investigated in rodents using the mouse intestinal transit model and acetylcholine (ACh, 10-9 to 10-4 M) and calcium (CaCl2, 10-4 to 10-1 M)-induced contractions of isolated rat jejunum. Similar to atropine (1 mg/kg), oral doses of ethanolic extract (EE) of J. gossypiifolia (500, 1000 and 2000 mg/kg) produced a decrease in intestinal transit (37.6 to 57.1 percent) when compared with control. The ACh-induced contraction in the jejunum was inhibited by EE (0.5, 1.0 and 2.0 mg/mL), chloroformic (CF) and aqueous fractions (0.1 and 0.5 mg/mL) and methanolic subfraction (0.05 and 0.25 mg/mL), suggesting an antimuscarinic mechanism. CaCl2 - induced responses in jejunum were also attenuated in the presence of CF (0.05 and 0.1 mg/mL) implying a direct interference of CF with the influx of calcium ions in the cells. Only the organic fraction of the extract had a calcium-antagonist effect, whereas both chloroformic and aqueous fractions had anticholinergic effect. These results suggest that the antispasmodic effect of J. gossypiifolia may be due a combination of anticholinergic and calcium antagonist mechanisms.

Role of electrostatic and hydrophobic forces in the interaction of ionic dyes with charged micelles.

The nature and strength of the interactions between a cationic fluorophore, Rhodamine 123 (R123), and surfactants of different head charge are investigated. Series of absorption and fluorescence emission spectra and of fluorescence decays are measured. R123 does not interact with the monomers of both nonionic and cationic surfactants but it presents affinity to their micelles. A partition equilibrium model was proposed and the corresponding equilibrium constants were obtained, as well as the photophysical properties of the dye bound to the micelles. In the case of the cationic surfactants, changes of the fluorescence properties were already observed below the critical micellar concentration (CMC) due to dynamic quenching caused by the free counterions. In the presence of anionic surfactants R123 shows a very different behaviour with dramatic spectral changes below the CMC. The observed variations are attributed to a first, strong interaction between R123 and the surfactant monomers, which yields ionic pairs of singular photophysical properties and dominates at low surfactant concentrations, followed by the association of R123 with the surfactant premicellar and micellar aggregates at higher surfactant concentrations near the CMC. This behaviour results from the competition between the strong electrostatic interactions of the cationic dye with the anionic surfactant head groups and the hydrophobic forces stabilizing the dye inside the micelles. The results of this work illustrate the complex physicochemical and photophysical behaviour of a charged dye in micellar systems, which resembles the expected situation in similar systems such as biological membranes.

In vivo inhibition of gastric acid secretion by the aqueous extract of Scoparia dulcis L. in rodents.

The freeze-dried aqueous extract (AE) from the aerial parts of Scoparia dulcis was tested for its effects on experimental gastric hypersecretion and ulcer in rodents. Administration of AE to animals with 4h pylorus ligature potently reduced the gastric secretion with ED(50)s of 195 mg/kg (rats) and 306 mg/kg (mice). The AE also inhibited the histamine- or bethanechol-stimulated gastric secretion in pylorus-ligated mice with similar potency suggesting inhibition of the proton pump. Bio-guided purification of the AE yielded a flavonoid-rich fraction (BuF), with a specific activity 4-8 times higher than the AE in the pylorus ligature model. BuF also inhibited the hydrolysis of ATP by H(+),K(+)-ATPase with an IC(50) of 500 microg/ml, indicating that the inhibition of gastric acid secretion of Scoparia dulcis is related to the inhibition of the proton pump. Furthermore, the AE inhibited the establishment of acute gastric lesions induced in rats by indomethacin (ED(50)=313 mg/kg, p.o.) and ethanol (ED(50)=490 mg/kg, p.o.). No influence of the AE on gastrointestinal transit allowed discarding a possible CNS or a cholinergic interaction in the inhibition of gastric secretion by the AE. Collectively, the present data pharmacologically validates the popular use of Scoparia dulcis in gastric disturbances.

Uptake of phenol from aqueous solutions by adsorption in a Pinus pinaster bark packed bed.

The adsorption of phenol from aqueous solutions using a column packed with pre-treated Pinus pinaster bark was studied. The influence of the inlet phenol concentration (0.01 or 0.1 g/L) and the flow rate (6, 15.6 or 30 mL/min) on the breakthrough curves was analysed. An increase in the flow rate, decreased the time necessary to reach the breakthrough point and, for the highest inlet concentration, the dynamic capacity of the bed, from 7.5 to 0.4 min and from 0.38 to 0.15 mg phenol/go.d. bark, respectively, at 0.1 g/L. The LUB Design Approach was used to determine the equivalent length of unused bed. The lower LUB values, which imply a better utilization of the bark bed, were obtained at the higher flow rate. A model which considered the effect of axial dispersion was successfully used to describe the fixed-bed operation behaviour for the lower flow rates. For the lowest inlet phenol concentration, the axial dispersion coefficient increased significantly when the flow rate increased.

Efeito da ropivacaína na recaptação neuronal de noradrenalina em músculo liso / Effect of ropivacaine on neuronal norepinephrine reuptake in smooth muscle

JUSTIFICATIVA E OBJETIVOS: Além da ação anestésica local, a ropivacaína apresenta efeito vasoconstritor, clinicamente significativo, que pode ser observado quando da anestesia infiltrativa, o que a torna um anestésico importante no bloqueio de campo. Este trabalho teve por objetivo caracterizar o mecanismo de ação constritora da ropivacaína em músculo liso. MÉTODO: Em preparações isoladas de ducto deferente de ratos foram construídas curvas concentração-efeito de noradrenalina na ausência ou na presença da ropivacaína. Em outra série de experimentos os ratos foram tratados com reserpina (10 mg.kg-1, por via intraperitoneal) para avaliar a reatividade dos ductos deferentes à tiramina ou noradrenalina, na ausência ou presença da ropivacaína. RESULTADOS: A ropivacaína nas concentrações de 5 ou 10 æg.mL-1 potencializou o efeito máximo (Emax) da noradrenalina em 47 por cento e 35 por cento, respectivamente, enquanto que nas concentrações de 50 ou 100 æg.mL-1 inibiu o efeito máximo produzido por este agonista. Em ductos deferentes isolados de ratos reserpinizados, a ropivacaína (10 ou 20 æg.mL-1) potencializou (150 por cento e 25 por cento, respectivamente) as contrações induzidas pela noradrenalina, enquanto que as concentrações de 50 ou 100 æg.mL-1 não alteraram as respostas à noradrenalina. CONCLUSÕES: Os resultados obtidos permitem concluir que a ropivacaína bloqueia a recaptação neuronal de noradrenalina pelos terminais nervosos simpáticos.

[Effect of ropivacaine on neuronal norepinephrine reuptake in smooth muscle.]. / Efeito da ropivacaína na recaptação neuronal de noradrenalina em músculo liso.

BACKGROUND AND OBJECTIVES: In addition to local anesthetic action, ropivacaine has clinically significant vasoconstrictor effects, which may be observed at infiltrative anesthesia, making it an important anesthetic for field blockade. This study aimed at characterizing the constrictor mechanism of ropivacaine on smooth muscles. METHODS: Norepinephrine concentration-effect curves in the absence or presence of ropivacaine were plotted on isolated preparations of vas deferens of rats. In another series of experiments rats were treated with reserpine (10 mg.kg-1, i.p.) to evaluate vas deferens reactivity to tyramine or norepinephrine, in the absence or presence of ropivacaine. RESULTS: Ropivacaine 5 or 10 microg.mL-1 potentiated maximum norepinephrine effect (Emax) in 47% and 35%, respectively, while higher concentrations (50 or 100 microg.mL-1) inhibited its maximum effect. In isolated vas deferens of rats treated with reserpine, ropivacaine (10 or 20 microg.mL-1) potentiated (150% and 25%, respectively) norepinephrine-induced contractions, while higher concentrations (50 or 100 microg.mL-1) have not changed responses to norepinephrine. CONCLUSIONS: Ropivacaine blocks neuronal norepinephrine reuptake by sympathetic nerve terminals.

Hypotensive and vasorelaxant effects of ethanolic extract from Jatropha gossypiifolia L. in rats.

The present work was carried out to examine the hypotensive effects of ethanolic extract (EE) from Jatropha gossypiifolia L. The oral administration of EE (125 or 250 mg kg(-1) day(-1)) caused a significant and dose-dependent reduction of the systolic blood pressure. The concentration-response curves to norepinephrine (NE) or Ca(2+) were non-parallelly shifted to the right and the maximum contractile responses were concentration dependently depressed by EE (0.1 or 0.5 mg/ml) in endothelium-deprived mesenteric artery. The cumulative additions of EE (0.1-30 mg/ml) caused a concentration-dependent relaxant response in endothelium-deprived mesenteric artery precontracted with NE or Ca(2+). In conclusion, our results have shown that the EE from J. gossypiifolia L. can elicit hypotension, by oral via, in conscious normotensive rats and vasorelaxant activity on rat mesenteric rings precontracted with NE or Ca(2+).

Morphological, cytological, and cultural aspects of Curvularia pallescens

Curvularia pallescens Boedijn (Hyphomycetes) is redescribed with the aid of scanning electron microscope, and the optimal cultural conditions for growing this fungus are discussed. Cytological analysis and nuclear condition, observed through the HCl-GIEMSA techique, showed vegetative and reproductive structures (hypha and conidia) formed by uni, bi, tri, and multinucleated segments. Cultures of C. pallescens in Complete Medium and in Potato Dextrose Agar varied on growth, on aspects of the border of the colonies and also on medium pigmentation. The Complete Medium and the temperature between 25-28degreeC were the most indicated for growth of C. pallescens.

Analgesic activity of a triterpene isolated from Scoparia dulcis L. (vassourinha)

Analgesic and anti-inflammatory activities of water (WE) and ethanolic (EE) extracts of Scoparia dulcis L. were investigated in rats and mice, and compared to the effects induced by Glutinol, a triterpene isolated by purification of EE. Oral adminsitration (p.o.) of either WE or EE (up to 2 g/Kg) did not alter the normal spontaneous activity of mice and rats. The sleeping time induced by sodium pentobarbital (50 mg/Kg, i.p.) was prolonged by 2 fold in mice pretreated with 0.5 g/Kg EE, p.o. Neither extract altered the tail flick response of mice in immersion test, but previous administration of EE (0.5 g/Kg, p.o.) reduced writhings induced by 0.8% acetic acid (0.1 ml/10 g, i.p.) in mice by 47% EE (0.5 and 1 g/Kg, p.o.) inhibited the paw edema induced by carrageenan in rats by respectively 46% and 58% after 2 h, being ineffective on the paw edema induced by dextran. No significant analgesic or anti-edema effects were detected in animals pretreated with WE (1 g/Kg, p.o.). Administration of Glutinol (30 mg/Kg, p.o.) reduced writhing induced by acetic acid in mice by 40% and the carrageenan induced paw edema in rats by 73%. The results indicate that the analgesic activity of S dulcis L. may be explained by explained by an anti-inflammatory activity probably related to the triterpene Glutinol.