Homogalactanas sulfatadas da alga Codium isthmocladum com atividade anticoagulante

Since the first description of sulfated polysaccharides from seaweeds, the biological activities of these compounds have been evaluated under different aspects and experimental procedures. Among the broad biological activities presented by seaweed polysaccharides, anticoagulant action appears as a promising function. In this present study we have obtained sulfated polysaccharides from the green seaweed Codium isthmocladium by proteolytic digestion, followed by separation into five fractions (0.3, 0.5, 0.7, 0.9 and 1.2) by sequential acetone precipitation. The chemical analyses have demonstrated that all fractions are composed mainly by sulfated polysaccharides. The anticoagulant activity of these fractions was determined by activated partial thromboplastin time (aPTT) and prothrombin time test (PT) using citrate normal human plasma. None fraction has shown anticoagulant activity by PT test. Furthermore, all of them have shown anticoagulant activity by aPTT test. These results indicated that the molecular targets of these sulfated polysaccharides are mainly in the intrinsic via of the coagulation cascade. Agarose gel electrophoresis in 1,3-diaminopropane acetate buffer, pH 9.0, stained with 0.1% toluidine blue showed the presence of two or three bands in several fractions while the fraction 0.9 showed a single spot. By anion exchange chromatography, the acid polysaccharides from the 0.9 acetone fraction were separated into two new fractions eluted respectively with 2.0 and 3.0 M NaCl. These compounds showed a molecular weight of 6.4 and 7.4 kDa respectively. Chemical analyses and infrared spectroscopy showed that Gal 1 and Gal 2 are sulfated homogalactans and differ one from the other in degree and localization of sulfate groups. aPPT test demonstrated that fractions 2,0 and 3,0M (Gal1 and Gal 2, respectively) have anticoagulant activity. This is the first time that anticoagulant sulfated homogalatans have been isolated from green algae. To prolong the coagulation time to double the baseline value in the aPTT, the required amount of sulfated galactan 1 (6,3mg) was similar to low molecular heparin Clexane®, whereas only 0,7mg of sulfated galactan 2 was needed to obtain the same effect. Sulfated galactan 2 in high doses (250mg) induces platelet aggregation. These results suggest that these galactans from C. isthmocladum have a potential application as an anticoagulant drug

Medição da densidade óssea através de ondas eletromagnéticas e classificação por MVS

This work holds the purpose of presenting an auxiliary way of bone density measurement through the attenuation of electromagnetic waves. In order to do so, an arrangement of two microstrip antennas with rectangular configuration has been used, operating in a frequency of 2,49 GHz, and fed by a microstrip line on a substrate of fiberglass with permissiveness of 4.4 and height of 0,9 cm. Simulations were done with silica, bone meal, silica and gypsum blocks samples to prove the variation on the attenuation level of different combinations. Because of their good reproduction of the human beings anomaly aspects, samples of bovine bone were used. They were subjected to weighing, measurement and microwave radiation. The samples had their masses altered after mischaracterization and the process was repeated. The obtained data were inserted in a neural network and its training was proceeded with the best results gathered by correct classification on 100% of the samples. It comes to the conclusion that through only one non-ionizing wave in the 2,49 GHz zone it is possible to evaluate the attenuation level in the bone tissue, and that with the appliance of neural network fed with obtained characteristics in the experiment it is possible to classify a sample as having low or high bone density

Homogalactanas sulfatadas da alga Codium isthmocladum com atividade anticoagulante

Since the first description of sulfated polysaccharides from seaweeds, the biological activities of these compounds have been evaluated under different aspects and experimental procedures. Among the broad biological activities presented by seaweed polysaccharides, anticoagulant action appears as a promising function. In this present study we have obtained sulfated polysaccharides from the green seaweed Codium isthmocladium by proteolytic digestion, followed by separation into five fractions (0.3, 0.5, 0.7, 0.9 and 1.2) by sequential acetone precipitation. The chemical analyses have demonstrated that all fractions are composed mainly by sulfated polysaccharides. The anticoagulant activity of these fractions was determined by activated partial thromboplastin time (aPTT) and prothrombin time test (PT) using citrate normal human plasma. None fraction has shown anticoagulant activity by PT test. Furthermore, all of them have shown anticoagulant activity by aPTT test. These results indicated that the molecular targets of these sulfated polysaccharides are mainly in the intrinsic via of the coagulation cascade. Agarose gel electrophoresis in 1,3-diaminopropane acetate buffer, pH 9.0, stained with 0.1% toluidine blue showed the presence of two or three bands in several fractions while the fraction 0.9 showed a single spot. By anion exchange chromatography, the acid polysaccharides from the 0.9 acetone fraction were separated into two new fractions eluted respectively with 2.0 and 3.0 M NaCl. These compounds showed a molecular weight of 6.4 and 7.4 kDa respectively. Chemical analyses and infrared spectroscopy showed that Gal 1 and Gal 2 are sulfated homogalactans and differ one from the other in degree and localization of sulfate groups. aPPT test demonstrated that fractions 2,0 and 3,0M (Gal1 and Gal 2, respectively) have anticoagulant activity. This is the first time that anticoagulant sulfated homogalatans have been isolated from green algae. To prolong the coagulation time to double the baseline value in the aPTT, the required amount of sulfated galactan 1 (6,3mg) was similar to low molecular heparin Clexane®, whereas only 0,7mg of sulfated galactan 2 was needed to obtain the same effect. Sulfated galactan 2 in high doses (250mg) induces platelet aggregation. These results suggest that these galactans from C. isthmocladum have a potential application as an anticoagulant drug

Câncer de boca e orofaringe: tendências e análise de sobrevida em Natal (RN)

Introduction: Mouth cancer is classified as having one of the ten highest cancer incidences in the world. In Brazil, the incidence and mortality rates of oral cancer are among the highest in the world. Intraoral cancer (tongue, gum, floor of the mouth, and other non-specified parts of the mouth), the accumulated survival rate after five years is less than 50%. Objectives: Estimate the accumulated survival probability after five years and adjust the Cox regression model for mouth and oropharyngeal cancers, according to age range, sex, morphology, and location, for the city of Natal. Describe the mortality and incidence coefficients of oral and oropharyngeal cancer and their tendencies in the city of Natal, between 1980 and 2001 and between 1997 and 2001, respectively. Methods: Survival data of patients registered between 1997 and 2001 was obtained from the Population-based Cancer Record of Natal. Differences between the survival curves were tested using the log-rank test. The Cox proportional risk model was used to estimate risk ratios. The simple linear regression model was used for tendency analyses of the mortality and incidence coefficients. Results: The probability after five years was 22.9%. The patients with undifferentiated malignant neoplasia were 4.7 times more at risk of dying than those with epidermoid carcinoma, whereas the patients with oropharyngeal cancer had 2.0 times more at risk of dying than those with mouth cancer. The mouth cancer mortality and incidence coefficients for Natal were 4.3 and 2.9 per 100 000 inhabitants, respectively. The oropharyngeal cancer mortality and incidence coefficients were, respectively, 1.1 and 0.7 per 100 000 87 inhabitants. Conclusions: A low survival rate after five years was identified. Patients with oropharyngeal cancer had a greater risk of dying, independent of the factors considered in this study. Also independent of other factors, undifferentiated malignant neoplasia posed a greater risk of death. The magnitudes of the incidence coefficients found are not considered elevated, whereas the magnitudes of the mortality coefficients are high

Estudo epidemiológico das parasitoses oculares na população de escolares da cidade de Natal-RN, Brasil

The objective of this study is to estimate the prevalence of Ocular Toxocariasis, Diffuse Unilateral Subacute Neuroretinitis (DUSN), Toxoplasma gondii infection and Ocular Toxoplasmosis in a student population in Natal-RN/Brazil and relate it to demographic, epidemiologic and socio-economic risk factors. The incidence of DUSN was observed in patients at the Federal University of Rio Grande do Norte Ophthalmology Service and the Prontoclinica de Olhos Ophthalmology clinic in Natal. In cases where a worm was found in the subretinal space, the result of treatment with photocoagulation using Green Laser (Eye Light ALCON) was evaluated in relation to final visual result. The sample was randomly selected among the schools of the four districts of Natal, according to the type of institution (public or private), its level (elementary or secondary), and study period (morning, afternoon or evening). The school population was studied from March to May, 2001. Initially, the students answered a questionnaire to evaluate demographic, epidemiologic and socio-economic risk factors. Afterwards, the following procedures were carried out: blood samples were taken for Toxoplasmosis (IgG, IgM) serology, hemogram, ophthalmological examination, consisting of clinical history, measurement of visual acuity, refraction under cycloplegia, biomicroscopy of the anterior segment and annexa, funduscopy and examination of extrinsic motility. The prevalence of Toxocariasis was 0.2% or 2 per one thousand students. The sample was insufficient to estimate the prevalence of DUSN. Seventy patients with DUSN diagnosis were examined from January, 2001 to January, 2003. A live worm was found in the subretinal space of all four patients in the acute phase, and these were treated with laser photocoagulation. After follow-up (average = 11.5 months), visual acuity improved in three eyes and remained unaltered in one eye. Worms were found in 22 of the 66 patients in the chronic phase, and these also were treated with laser photocoagulation. After a follow-up period of 13.1 months, on average, visual acuity improved in two of the patients, remained unchanged in 19 and worsened in one. The comparison of visual result before and after treatment was not statistically significant (p = 0.302). The diagnosis of DUSN in the acute phase, followed by prompt localization and destruction of the worm by photocoagulation, can improve the patient s vision. However, destruction of the worm by laser photocoagulation in eyes with DUSN in the chronic phase does not improve visual acuity. Seroprevalence for IgG was 46% (Confidence Interval CI 95%-42.9-49.2%) and for IgM it was 1.4% (CI 95% = 0.8-2.4%). The prevalence of ocular lesion was 1.15% (CI 95% = 0.6 - 2.0%). Socio-economic conditions were determinants in the prevalence of Systemic and Ocular Toxoplasmosis in the bivaried analysis and confirmed in the multivaried analysis (mother s scholarity illiterate/ OR = 2.9 and p < 0.001). The T. gondii infection prevalence, although high, was less than that found in studies performed in the South and Southeast of Brazil and that of Ocular Toxoplasmosis was completely discrepant, varying from 5 to 17 times less. Although important epidemiological variables such as owning a cat, drinking unfiltered water, and coming into contact with rivers or lakes showed an association in the preliminary analysis, they lost their influence when included in the logistic model. Future studies are scheduled to begin in March, 2004, in collaboration with other Brazilian and American universities in an attempt to discover the reason for these findings, as well as identifying the different strains of Toxoplasma gondii, and studying the sources of water utilized by the population of Natal Brazil

Biodistribution of the radiophamarceutical sodium pertechnetate (Na99mTcO4) after massive small bowel resection in rats

To evaluate the biodistribution of sodium pertecnetate (Na99mTcO4) in organs and tissues, the morphometry of remnant intestinal mucosa and ponderal evolution in rats subjected to massive resection of the small intestine. Methods: Twenty-one Wistar rats were randomly divided into three groups of 7 animals each. The short bowel (SB) group was subjected to massive resection of the small intestine; the control group (C) rats were not operated on, and soft intestinal handling was performed in sham rats. The animals were weighed weekly. On the 30th postoperative day, 0.l mL of Na99mTcO4, with mean activity of 0.66 MBq was injected intravenously into the orbital plexus. After 30 minutes, the rats were killed with an overdose of anesthetic, and fragments of the liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, femur and brain were harvested. The biopsies were washed with 0.9% NaCl.,The radioactivity was counted using Gama Counter WizardTM 1470, PerkinElmer. The percentage of radioactivity per gram of tissue (%ATI-g) was calculated. Biopsies of the remaining jejunum were analysed by HE staining to obtain mucosal thickness. Analysis of variance (ANOVA) and the Tukey test for multiple comparisons were used, considering p<0.05 as signifi cant. Results: There were no signifi cant differences in %ATI-g of the Na99mTcO4 in the organs of the groups studied (p>0.05). An increase in the weight of the SB rats was observed after the second postoperative week. The jejunal mucosal thickness of the SB rats was signifi cantly greater than that of C and sham rats (p<0.05). Conclusion: In rats with experimentally-produced short bowel syndrome, an adaptive response by the intestinal mucosa reduced weight loss. The biodistribution of Na99mTcO4 was not affected by massive intestinal resection, suggesting that short bowel syndrome is not the cause of misleading interpretation, if an examination using this radiopharmaceutical is indicated

Influência da profundidade e dos parâmetros ambientais sobre o desenvolvimento de Gracilaria birdiae (Rhodophyta, Gracilariales) em viveiro de camarão

This study evaluates the influence of depth and environmental parameters on the development of Gracilaria birdiae Plastino & Oliveira (Gracilariaceae Rhodophyta) in an organic shrimp pound (Litopenaeus vannamei) under euthrophical conditions. PVC structures (module) witch four ropes laden with 150 g of macroalgae each, were kept during 35 days at three different depths (surface, 10 and 20 cm depth). Wet biomass weighing and environmental parameters (temperature, salinity, turbidity, pH, transparence, precipitation, evaporation, insolation, accumulated solar radiation, nitrite, nitrate, ammonium and orthophosphate) were measured weekly. At all three proposed depths, the macroalgae displayed a higher biomass at the end of experiment than at the initial inoculations. The module kept at a 10 cm depth presented the greatest average biomass (186,3), followed by that kept at 20 cm (180,4 g) and the surface module (169,9 g). Biomass variations showed algae to suffer the direct effects of depths. Biomass loss was associated with the factors that influence light penetration, such as sediment deposits above the thallus, rate of evaporation and precipitation. The smallest loses occurred in the algae kept on surface (0,16%), followed by the algae kept at 20 cm (0,20%) and 10 cm (0,22%). The specific growth rate (SGR) of G. birdiae showed no significant difference between the three depths nor the sample periods. Nevertheless, the modules kept at 10 and 20 cm depths presented similar growth evolution, both growing 0,38%·per day-1, while the module kept on surface had an average SGR of 0,36%·day-1. The models related to growth rate demonstrated temperature, salinity, pH, orthophosphate, ammonium, precipitation and turbidity as the principal environmental parameters influencing the development of G. birdiae

HIV/AIDS e estilo de vida: parâmetros imunológicos, virológicos, síndrome lipodistrófica e sua relação com a prática de exercícios

This descriptive study aimed to investigate the relationship between expression of immunological (TCD4 +) and virological (viral load) parameters, lipodystrophy syndrome and lifestyle variables of people living with HIV who underwent a program of physicalexercise. Initially, the sample was composed by 17 persons, recorded at the Department of Giselda Trigueiro Hospital Care (GTH), Natal-RN . With the passing of the stages of intervention (physical training program- PTP) the number of participants has changed (17, 9, 8 and 7) as the training phases (I, II, III and IV). Data collected were on total cholesterol, High Density Lipoprotein (HDL) and triglycerides. The % fat (% F), body mass index (BMI), waist-hip ratio (WHR), lean mass (LM), central fat (BF), total (TF) and peripheral (PF), weight and height were used to measure the morphological parameters. For control of variables (TCD4 +, viral load, Triglycerides, Cholesterol, HDL), the information contained in the blood tests every four months were investigated. After Phase I and II, it was used a structured interview. Then sampling was carried out considering the pre-and post-tests 1, 2, 3 and 4 (after 16, 32, 48 and 64 weeks of training, respectively). Daily, the intensity of the work was checked by the scale of perceived exertion for exercises adapted to resistance34. Procedures used were descriptive statistics (dispersion, absolute and relative frequencies, means, standard deviations and minimum and maximum values) as well as Spearman linear correlation adopting a significance level of p ≤ 0.05. Positive changes were observed for TCD4 + and viral load in all phases of the PTP. For the morphological components, the loss of central subcutaneous fat (CSF) and total subcutaneous fat (TSF) for both sexes and the decrease in % BF among women were the most dramatic results after the training phase I. For men, results were more significant to % F and LM in Phases I and II and peripheral subcutaneous fat (PSF) declined in all phases of the exercise. As for women, results were more expressive for % F and TM in the phases I and II and the PSF decreased in all phases of the exercise. Whereas for women, the waist/hip ratio (WCQ) and 0% F decreased and showed a positive association with triglycerides (WHR r * 0.82, p 0.042, r 0.88 TSF *, p 0.019 and r 1.00 ** CSF, p <0.001) and among men with limb subcutaneous fat (LSF)* r 0.65, p 0.029). The PTP provided improvement in the health, self-esteem and quality of life, proving to be a possible strategy to positively influence the expression of immunological parameters (TCD4 +) and virological (viral load) and morphological components of people living with HIV causing no deleterious effects in these parameters

Estudo do comportamento mecânico de areias artificialmente cimentadas

Soil improved with the addition of cement have been utilized as an alternative to the construction of various types of geotechnical works, almost always present economic and environmental advantages. This paper presents a study on the usage of cement in the improvement of mechanical properties of sandy soils, characteristic of the region of Natal, collected from its dunes. This research was made in order to analyze the influence of cement content, voids, and also including water immersion and confining pressure. Samples molded from cement-soil mixtures were tested for unconfined compression tests and triaxial tests. The samples had the percentage of cement mixed in 2.5%, 5% and 10% by weight. The cement agent used was the Portland Cement of High Early strength(CPV-ARI), which promoted agility to the experimental procedure for presenting a rapid gain in strenght. The void ratio used ranged from 0.7 (more compact), 0,9 and 1,1(softer). The soil under study can be considered as pure sand. In general, it can be stated that the larger the amount of cement added to the sand studied is, the greater ultimate strength will be. Likewise, as more compact the soil is, the less void ratio and more resistant it will be present. The confining pressure tends to increase the resistance of the specimens. The cementing adopted grades showed that the use of different criteria for failure did not significantly alter the stress-strain parameters for the sand studied. The angle of friction values were found within the typical range of medium and compact sands. Cementing acted in the sand providing an intercepted cohesion which increased enhancing the potential cementation. In triaxial compression tests, the sand with void ratio is equal to 0.7 and showed the expected behavior for a compact sand while the stress-strain behavior of the same sand with the void ratio of 0.9 tended to be expected for the soft sand as well

Desenvolvimento de compósito de pu de mamona com carga de resíduo de couro para isolação térmica

The standardization of the bovine skin thickness in the leather industry generates a residue known as wet-blue . At the end of twentieth century, the brazilian industry discarded about 131 thousand tons of this residue in nature, provoking a great environmental liability. In this paper is presented the analyses of the termophysical properties, thermal and volumetric expansion performance of a composite of vegetable resin of castor oil plant (Ricinus communis) with load of industrial residue of leather "wet-blue", for application as thermal isolation material of warm surfaces. There were considered four percentile levels of residue load in the proportions in mass of 0%, 5%, 10% and 15%, added to the expansible resin of castor oil plant in two configurations: sawed leather and crushed leather in a smaller particle (powder) by grinding in a mill of balls. Twenty-one proof bodies were produced for termophysical properties analysis (three for each configuration) and four proof bodies for rehearsals of thermal acting. Analyses of thermal acting were done in test cameras. The results of the rehearsals were compared to those obtained considering the castor oil plant foam without residue addition. A small reduction of the thermal conductivity of the composite was observed in the proportion of 10% of leather residue in both configurations. Regarding thermal conductivity, calorific capacity and diffusivity, it was verified that the proposed composite showed very close values to the commercial insulating materials (glass wool, rock wool, EPS). It was still demonstrated the technical viability of the use of composite as insulating thermal for systems of low potency. The composite presented larger volumetric expansion with 15% of sawed residue of leather.

Estrutura genética de populações de Amphobotrys ricini, agente causal do mofo cinzento da mamoneira

The gray mold, causal organism Amphobotrys ricini, is one of the major diseases of castor bean. Difficulties in managing plant disease arises form the limited understanding of the genetic structure of A. ricini, their complexity and variability make it difficult to control. Genetic structure can be used to infer the relative impact of different forces that influence the evolution of pathogen populations, that allow to predict the potencial for pathogen populations to envolve in agricultural ecosystems. Growers protect their crop by applying fungicides, but there aren t fungicides to provide significant control of gray mold of castor bean. The objectives of this work were use RAPD to determine the genetic structure of A. ricini subpopulations in Paraíba and assay the sensitivity of A. ricini isolates to azoxystrobin and carbendazim. To determine the genetic structure of A. ricini subpopulations in Paraíba, 23 isolates were colleted from two different geographic location (subpopulation). These isolates were analysed by RAPD using 22 random decamer primers, purchased from OPERON, produced a total of 80 markers polimorphics. The resulting matrixes were analysed using PopGene version 1.32. Sensitivity to azoxystrobin and carbendazim of 30 isolates, colleted form Paraíba and Alagoas, was estimated based on spore germination and colony growth inhibition. The stock solutions were added toV8 medium after sterilization to produce final concentrations of 0, 0.01, 0.1, 1, 10, and 100 µg/ml of carbendazim and 0, 0.001, 0.01, 0.1, 1, and 10 µg/ml of azoxystrobin. All statistical analyses were performed using SAS to estimate the dose that inhibited fungal growth by 50% (ED50 values). The genetic diversity within subpopulations (Hs=0,271) accounted for 92% of the total genetic diversity (Ht=0,293), while genetic diversity between subpopulations (Gst = 0,075) represented only 7,5%. The estimated number of migrants per generation (NM ) was 6,15. Nei s average gene identity across 80 RAPD loci was 0,9468. Individual ED50 values, for the 30 isolates screened for their sensitivity to azoxystrobin, ranged From a maximum of 0,168 µg/ml to a minimum of 0,0036 µg/ml. The ED50 values for carbendazim varied within the range of 0,026 to 0,316 µg/ml