Intraventricular hemorrhage as clinical presentation of herpes simplex virus encephalitis. A case report and review of the literature.

OBJECTIVE: Herpes simplex virus encephalitis (HSVE) represents the most common cause of sporadic encephalitis in humans. The development of intracerebral hematomas is rare and late during the course of HSVE. To report a case of a patient with HSVE who initially presented a diffuse intracranial hemorrhage with predominant intraventricular bleeding. CASE REPORT: A 66-year-old man was admitted to the Emergency Department with acute headache. Antecedents: alcohol consumption and ethylic hepatopathy. The brain computed tomography showed acute tetraventricular hemorrhage and hydrocephalus. The blood analysis showed pancytopenia and alteration of all hepatic parameters. After external drainage of cerebrospinal fluid the patient presented a worsening of headache, disorientation, mild left hemiparesis, neck stiffness and temperature of 37.6 °C. The cerebrospinal fluid was hemorrhagic, with 3 lymphocytes/mm3, 60 mg/dL of proteins and PCR positive for Herpes simplex virus type 1. The patient improved with intravenous acyclovir, however he experienced several medical complications which caused his dead. DISCUSSION: The patient presented an atypical cerebral bleeding related to HSVE because the development of hematoma was early and the topography of hemorrhage was basically intraventricular. Probably, both atypical characteristics were related to thrombocytopenia and severe coagulation disorder. This case expands the spectrum of cerebrovascular disorders associated with HSVE.

Interfacial aggregation of Janus rods in binary polymer blends and their effect on phase separation.

Janus particles interfacially self-assemble into different structures when incorporated into multiphase systems. Dissipative particle dynamics simulations are employed herein to investigate the interplay between aggregation mechanisms and phase separation in polymer blends. Shorter rods with a standing configuration become increasingly "caged" or trapped in larger aggregates as weight fraction increases, which is reflected in the way that their diffusion is coupled to their aggregation rates. Janus rods of higher aspect ratios that are tilted at the interface aggregate side-by-side and are able to hinder phase separation kinetics. This is due to a combination of individual Janus rod conformations at the interface, their intrinsic aggregation mechanisms, aggregate fractal dimension, and aggregation rates, and can also be traced back to the scaling of the diffusion coefficient of aggregates with their size. Findings presented provide insight into the mechanisms governing two dimensionally growing colloidal aggregates at fluid interfaces, more specifically, those associated with Janus particles, and shed light on the potential of these systems in paving the way for designing new functional materials.

Diaphanocephalus galeatus (Nematoda: Diaphanocephalidae), a poorly known parasite of lizards: redescription, first genetic characterization and a revision of its congeners from Brazil.

Diaphanocephalus galeatus collected from the small intestine of the lizard Dracaena paraguayensis in the Pantanal wetlands, State of Mato Grosso do Sul, Brazil, is redescribed. Genetic characterization and observations using scanning electron microscopy (SEM) were performed for the first time. The vouchers of D. galeatus and the type specimens of its congeners, deposited in the Coleção Helmintológica do Instituto Oswaldo Cruz (CHIOC), were consulted. Light and SEM observations revealed several undescribed features of D. galeatus, i.e. structure of the cephalic end and of the buccal capsule, position and morphology of deirids, presence of phasmids in females and presence of unpaired papilla on the membranous projection that covers the genital cone in males. After observation of the specimens deposited in the helminthological collection, D. jacuruxi is considered a synonym of D. galeatus, and D. diesingi, despite its incomplete description, is tentatively retained as valid due to the poor condition of the type material. The results also indicated low host specificity of D. galeatus, contradicting previous assertions. Genetic comparisons using patristic distances and phylogenetic trees generated from sequences of the 28S rRNA nuclear gene indicated that D. galeatus is closer to the taxa within Ancylostomatoidea and Strongyloidea than any lineage of Metastrongyloidea or Trichostrongyloidea. However, most of the nodal supports were low. Based on the genetic and morphological characterization, the validity of D. galeatus was confirmed. These data may serve for further comparative approaches for different populations of the parasite, from different hosts in different geographical areas, mitigating taxonomic confusions.

A new species of Raphidascaris (Nematoda: Raphidascarididae) infecting the fish Gymnogeophagus balzanii (Cichlidae) from the Pantanal wetlands, Brazil and a taxonomic update of the subgenera of Raphidascaris based on molecular phylogeny and morphology.

Raphidascaris (Sprentascaris) andersoni n. sp. (Nematoda: Raphidascarididae) collected in the intestine of the humphead cichlid Gymnogeophagus balzanii (Perugia) from the Pantanal wetlands, State of Mato Grosso do Sul (Brazil) is described and genetically characterized. The new species differs from its congeners mainly by having a conspicuous papilla-like formation slightly anterior to the cloacal aperture. Furthermore, males of R. (S.) lanfrediae and R. (S.) mahnerti have caudal alae, and R. (S.) hypostomi and R. (S.) pimelodi lack lateral alae, whereas in the new species caudal alae are absent and lateral alae present. The remaining congeners, namely, R. (S.) marano and R. (S.) saltaensis differ from Raphidascaris (Sprentascaris) andersoni n. sp. mainly because males have three pairs of postcloacal papillae (vs five pairs). In the phylogenetic reconstructions, using three nuclear genetic markers (18S, ITS1-5.8S-ITS2 and 28S rDNA) and one mitochondrial (cox1 mtDNA), the new species was separated from other representatives of Raphidascarididae, and the absence of monophyly in Hysterothylacium and Raphidascaroides was confirmed. Moreover, the subgenera Sprentascaris and Ichthyascaris appeared to be monophyletic. Therefore, even though Raphidascaris (Raphidascaris) was apparently not monophyletic, the subgenera of Raphidascaris should be re-erected as valid genera. The updated diagnoses of Ichthyascaris, Raphidascaris and Sprentascaris are given. The present study represents the first parasitological survey in G. balzanii.

Functional morphology of the tetra fish Astyanax lacustris differs between divergent habitats in the Pantanal wetlands.

This study investigated whether the body morphology of the tetra fish Astyanax lacustris (previously Astyanax asuncionensis) varied between populations inhabiting one lagoon (a lentic, shallow environment, with great habitat complexity created by aquatic macrophytes) and an adjacent river (a deeper, lotic environment where aquatic macrophytes are scarce) in a seasonally flooded wetland, despite population mixing during the wet season. Morphological differences matched a priori predictions of the theory relating functional body morphology and swimming performance in fishes between lagoon and river habitats. Observed morphological variation could have resulted from adaptive habitat choice by tetras, predation by piscivores and adaptive phenotypic plasticity during development.

Variation in the parasite community of the sardine fish Triportheus nematurus (Actinopterygii: Characidae) from the Medalha lagoon in the Pantanal wetland, Brazil.

In July 2009 and July 2010 (two dry periods separated by an atypically large flood in the Pantanal wetland of Brazil), 34 and 33 specimens of the sardine fish Triportheus nematurus were collected, respectively, for the study of the metazoan parasite community of this species. Parasite ecological and community descriptors were calculated for both host samples, and possible similarities were tested statistically. Five species of metazoan parasites were identified, four of which were common to both host samples. A total of 61 metazoan parasites were collected from all fish hosts (17 specimens in July 2009 (mean: 0.5 ± 0.66 parasites/fish) and 44 specimens in July 2010 (mean: 1.33 ± 1.41 parasites/fish)). The nematode Procamallanus hilarii and the monogenean Anacanthorus sp. were the most prevalent and abundant species in 2009 and 2010, respectively. The mean total abundance and species richness were significantly higher in 2010. Parasite communities in both samples of T. nematurus were characterized by species with low prevalence, abundance, mean total abundance and species richness, thus indicating low parasite diversity. Significant differences in the prevalence and abundance of P. hilarii and Anacanthorus sp. between the two samples allowed the discrimination of infracommunities, which were united in two distinct groups. This appears to be the first evidence that the peculiar hydrological dynamics of the southern Pantanal wetland (Brazil) exert an important influence over the structure of the parasite community.

Physiology and production of sugar-apple under water stress and application of proline.

The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba's semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.

Salicylic acid does not mitigate salt stress on the morphophysiology and production of hydroponic melon.

The excess of salts present in the water can limit the hydroponic cultivation of melon in semi-arid regions of the Brazilian Northeast, making it necessary to use strategies that allow the use of these waters. Among these strategies, the use of elicitor substances stands out, such as salicylic acid. In this context, this study aimed to evaluate the effect of foliar application of salicylic acid in mitigating the harmful effects of salt stress on the morphophysiology and production of 'Gaúcho' melon cultivated in a hydroponic system. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution - ECsn (2.1, 3.2, 4.3, and 5.4 dS m-1) considered the plots and four salicylic acid concentrations - SA (0, 1.5, 3.0, and 4.5 mM), the subplots, with six replications. The foliar application of salicylic acid concentrations did not mitigate the deleterious effects of salt stress on the morphophysiology and yield of melon grown in hydroponic system. The concentration of 4.5 mM of salicylic acid intensified the harmful effects of the salinity of the nutrient solution on gas exchange and fresh weight of hydroponic melon.

Characterization of spliced leader genes of Trypanosoma ( Megatrypanum) theileri: phylogeographical analysis of Brazilian isolates from cattle supports spatial clustering of genotypes and parity with ribosomal markers.

Trypanosoma (Megatrypanum) theileri from cattle and trypanosomes of other artiodactyls form a clade of closely related species in analyses using ribosomal sequences. Analysis of polymorphic sequences of a larger number of trypanosomes from broader geographical origins is required to evaluate the clustering of isolates as suggested by previous studies. Here, we determined the sequences of the spliced leader (SL) genes of 21 isolates from cattle and 2 from water buffalo from distant regions of Brazil. Analysis of SL gene repeats revealed that the 5S rRNA gene is inserted within the intergenic region. Phylogeographical patterns inferred using SL sequences showed at least 5 major genotypes of T. theileri distributed in 2 strongly divergent lineages. Lineage TthI comprises genotypes IA and IB from buffalo and cattle, respectively, from the Southeast and Central regions, whereas genotype IC is restricted to cattle from the Southern region. Lineage TthII includes cattle genotypes IIA, which is restricted to the North and Northeast, and IIB, found in the Centre, West, North and Northeast. PCR-RFLP of SL genes revealed valuable markers for genotyping T. theileri. The results of this study emphasize the genetic complexity and corroborate the geographical structuring of T. theileri genotypes found in cattle.

Integrative taxonomy of Sprentascaris mahnerti and phylogeny of raphidascaridid nematodes (Nematoda: Ascaridoidea: Raphidascarididae) suggest the monophyly of Sprentascaris.

Sprentascaris mahnerti (Nematoda: Raphidascarididae) collected from Loricariichthys labialis (Siluriformes: Loricariidae) in the Pantanal wetlands, State of Mato Grosso do Sul (Brazil), was redescribed using light and scanning electron microscopy (SEM), and genetically characterised along with two other raphidascaridids: Raphidascaroides brasiliensis and Ro. moraveci. Due to the systematic discussion regarding Raphidascaris and Sprentascaris, as well as the poor knowledge about the phylogenetic relationships within Raphidascarididae, phylogenies were reconstructed based on partial sequences of the 18S and 28S nuclear rRNA gene, the nuclear ITS1-5.8S-ITS2 and the cytochrome c oxidase subunit I (cox1) mtDNA. Morphological study of S. mahnerti, confirmed some previously described features, revealed new characteristics and permitted to elucidate some inconsistencies noted in the literature. Morphological and genetic characterisation of S. mahnerti supported its validity. Phylogenetic reconstructions supported the monophyly of Sprentascaris, which has three pairs of interlabial conspicuous cuticular projections as a synapomorphy. The relationships among several lineages of raphidascaridids were unsolved, albeit Goezia and Ichthyascaris formed well-supported monophyletic assemblages, in which the first included species with no relations regarding the habitat of hosts and the geographic origin. The present findings represent one more step towards the understanding of the interrelationships of raphidascaridid nematodes. In this sense, Sprentascaris should be considered valid as an independent lineage from Raphidascaris.

Pressure-induced phase transitions in DL-glutamic acid monohydrate crystal.

DL-glutamic acid monohydrate crystal was synthesized from an aqueous solution by slow evaporation technique. The crystal was submitted to high-pressure (1 atm-14.3 GPa) to investigate its vibrational behavior and the occurrence of phase transitions. We performed Raman spectroscopy as probe and through the analysis of the spectra we discovered three structural phase transitions. The first one occurs around 0.9 GPa. In this phase transition, glutamic acid molecules suffer modifications in their conformations while water molecules are less affected. The second phase transition at 4.8 GPa involves conformational changes related to CO2-, NH3+ units and the water molecules, while the third one, between 10.9 and 12.4 GPa, involves motions of several parts of the glutamic acid as well as the water molecules. Considering the dynamic of high pressure, the second phase of DL-glutamic acid monohydrate crystal presented a better stability compared with the second phase of its polymorphs α and ß L-glutamic acid. In addition, water molecules seem to play important role on this structural stability. All changes are reversible.

Evolutionary history of trypanosomes from South American caiman (Caiman yacare) and African crocodiles inferred by phylogenetic analyses using SSU rDNA and gGAPDH genes.

In this study, using a combined data set of SSU rDNA and gGAPDH gene sequences, we provide phylogenetic evidence that supports clustering of crocodilian trypanosomes from the Brazilian Caiman yacare (Alligatoridae) and Trypanosoma grayi, a species that circulates between African crocodiles (Crocodilydae) and tsetse flies. In a survey of trypanosomes in Caiman yacare from the Brazilian Pantanal, the prevalence of trypanosome infection was 35% as determined by microhaematocrit and haemoculture, and 9 cultures were obtained. The morphology of trypomastigotes from caiman blood and tissue imprints was compared with those described for other crocodilian trypanosomes. Differences in morphology and growth behaviour of caiman trypanosomes were corroborated by molecular polymorphism that revealed 2 genotypes. Eight isolates were ascribed to genotype Cay01 and 1 to genotype Cay02. Phylogenetic inferences based on concatenated SSU rDNA and gGAPDH sequences showed that caiman isolates are closely related to T. grayi, constituting a well-supported monophyletic assemblage (clade T. grayi). Divergence time estimates based on clade composition, and biogeographical and geological events were used to discuss the relationships between the evolutionary histories of crocodilian trypanosomes and their hosts.

A new genotype of Trypanosoma cruzi associated with bats evidenced by phylogenetic analyses using SSU rDNA, cytochrome b and Histone H2B genes and genotyping based on ITS1 rDNA.

We characterized 15 Trypanosoma cruzi isolates from bats captured in the Amazon, Central and Southeast Brazilian regions. Phylogenetic relationships among T. cruzi lineages using SSU rDNA, cytochrome b, and Histone H2B genes positioned all Amazonian isolates into T. cruzi I (TCI). However, bat isolates from the other regions, which had been genotyped as T. cruzi II (TC II) by the traditional genotyping method based on mini-exon gene employed in this study, were not nested within any of the previously defined TCII sublineages, constituting a new genotype designated as TCbat. Phylogenetic analyses demonstrated that TCbat indeed belongs to T. cruzi and not to other closely related bat trypanosomes of the subgenus Schizotrypanum, and that although separated by large genetic distances TCbat is closest to lineage TCI. A genotyping method targeting ITS1 rDNA distinguished TCbat from established T. cruzi lineages, and from other Schizotrypanum species. In experimentally infected mice, TCbat lacked virulence and yielded low parasitaemias. Isolates of TCbat presented distinctive morphological features and behaviour in triatomines. To date, TCbat genotype was found only in bats from anthropic environments of Central and Southeast Brazil. Our findings indicate that the complexity of T. cruzi is larger than currently known, and confirmed bats as important reservoirs and potential source of T. cruzi infections to humans.

Phylogenetic analysis of Trypanosoma vivax supports the separation of South American/West African from East African isolates and a new T. vivax-like genotype infecting a nyala antelope from Mozambique.

In this study, we addressed the phylogenetic and taxonomic relationships of Trypanosoma vivax and related trypanosomes nested in the subgenus Duttonella through combined morphological and phylogeographical analyses. We previously demonstrated that the clade T. vivax harbours a homogeneous clade comprising West African/South American isolates and the heterogeneous East African isolates. Herein we characterized a trypanosome isolated from a nyala antelope (Tragelaphus angasi) wild-caught in Mozambique (East Africa) and diagnosed as T. vivax-like based on biological, morphological and molecular data. Phylogenetic relationships, phylogeographical patterns and estimates of genetic divergence were based on SSU and ITS rDNA sequences of T. vivax from Brazil and Venezuela (South America), Nigeria (West Africa), and from T. vivax-like trypanosomes from Mozambique, Kenya and Tanzania (East Africa). Despite being well-supported within the T. vivax clade, the nyala trypanosome was highly divergent from all other T. vivax and T. vivax-like trypanosomes, even those from East Africa. Considering its host origin, morphological features, behaviour in experimentally infected goats, phylogenetic placement, and genetic divergence this isolate represents a new genotype of trypanosome closely phylogenetically related to T. vivax. This study corroborated the high complexity and the existence of distinct genotypes yet undescribed within the subgenus Duttonella.

Physalins B, F and G, seco-steroids purified from Physalis angulata L., inhibit lymphocyte function and allogeneic transplant rejection.

Physalis angulata is a solanaceae widely used in folk medicine in various tropical countries in the world. We have previously described that seco-steroids (physalins) purified from P. angulata are potent inhibitors of macrophage activation, blocking the production of pro-inflammatory cytokines and LPS-induced lethality. Herein we investigated the immunomodulatory activities of these substances in lymphocyte proliferation and cytokine production and in transplantation. The addition of physalins B, F or G to concanavalin A-activated splenocyte cultures induced a concentration-dependent inhibition of proliferation. Physalin B also inhibited IL-2 production by Con A-activated spleen cells. The addition of 2 mug/ml physalin B to mixed lymphocyte reaction (MLR) caused a 100% inhibition of proliferation. More importantly, treatment of mice with physalin B, F or G prevented the rejection of allogeneic heterotopic heart transplant. Our results demonstrate the suppressive activity of physalins B, F and G in lymphocyte function and indicate the potential use of physalins as immunosuppressive agents for treatments of pathologies in which inhibition of immune responses is desired.

Effects of disturbed blood flow during exercise on endothelial function: a time course analysis.

This study aimed to examine the time course of endothelial function after a single handgrip exercise session combined with blood flow restriction in healthy young men. Nine participants (28 ± 5.8 years) completed a single session of bilateral dynamic handgrip exercise (20 min with 60% of the maximum voluntary contraction). To induce blood flow restriction, a cuff was placed 2 cm below the antecubital fossa in the experimental arm. This cuff was inflated to 80 mmHg before initiation of exercise and maintained through the duration of the protocol. The experimental arm and control arm were randomly selected for all subjects. Brachial artery flow-mediated dilation (FMD) and blood flow velocity profiles were assessed using Doppler ultrasonography before initiation of the exercise, and at 15 and 60 min after its cessation. Blood flow velocity profiles were also assessed during exercise. There was a significant increase in FMD 15 min after exercise in the control arm compared with before exercise (64.09% ± 16.59%, P=0.001), but there was no change in the experimental arm (-12.48% ± 12.64%, P=0.252). FMD values at 15 min post-exercise were significantly higher for the control arm in comparison to the experimental arm (P=0.004). FMD returned to near baseline values at 60 min after exercise, with no significant difference between arms (P=0.424). A single handgrip exercise bout provoked an acute increase in FMD 15 min after exercise, returning to near baseline values at 60 min. This response was blunted by the addition of an inflated pneumatic cuff to the exercising arm.

Retinoic acid-loaded polymeric nanoparticles enhance vascular regulation of neural stem cell survival and differentiation after ischaemia.

Stroke is one of the leading causes of death and disability worldwide. However, current therapies only reach a small percentage of patients and may cause serious side effects. We propose the therapeutic use of retinoic acid-loaded nanoparticles (RA-NP) to safely and efficiently repair the ischaemic brain by creating a favourable pro-angiogenic environment that enhances neurogenesis and neuronal restitution. Our data showed that RA-NP enhanced endothelial cell proliferation and tubule network formation and protected against ischaemia-induced death. To evaluate the effect of RA-NP on vascular regulation of neural stem cell (NSC) survival and differentiation, endothelial cell-conditioned media (EC-CM) were collected. EC-CM from healthy RA-NP-treated cells reduced NSC death and promoted proliferation while EC-CM from ischaemic RA-NP-treated cells decreased cell death, increased proliferation and neuronal differentiation. In parallel, human endothelial progenitor cells (hEPC), which are part of the endogenous repair response to vascular injury, were collected from ischaemic stroke patients. hEPC treated with RA-NP had significantly higher proliferation, which further highlights the therapeutic potential of this formulation. To conclude, RA-NP protected endothelial cells from ischaemic death and stimulated the release of pro-survival, proliferation-stimulating factors and differentiation cues for NSC. RA-NP were shown to be up to 83-fold more efficient than free RA and to enhance hEPC proliferation. These data serve as a stepping stone to use RA-NP as vasculotrophic and neurogenic agents for vascular disorders and neurodegenerative diseases with compromised vasculature.

Remoción selectiva comparado con remoción total para caries dentinarias profundas / Selective removal compared to complete removal for deep carious lesions

INTRODUCCIÓN La caries dental ha sido convencionalmente manejada mediante la remoción no selectiva del tejido carioso (remoción total), sin embargo, los efectos adversos de este procedimiento han promovido la utilización de técnicas de remoción de caries conservadoras (remoción selectiva), pero aún existe controversia respecto a su efectividad. MÉTODOS Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metaanálisis, preparamos tablas de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos siete revisiones sistemáticas que en conjunto incluyeron siete estudios primarios, todos ellos correspondientes a ensayos aleatorizados. Concluimos que la remoción selectiva de caries podría disminuir la necesidad de tratamiento de endodoncia y el riesgo de exposición pulpar en dientes con caries profundas, pero la certeza de la evidencia es baja. No existe claridad de que la remoción selectiva de caries disminuya el riesgo de aparición de signos y síntomas de patología pulpar y el riesgo de fracaso de las restauraciones ya que la certeza de la evidencia es muy baja.

INTRODUCTION Dental caries have been conventionally managed by non-selective removal of carious tissue (total complete removal); however, the adverse effects of this procedure have promoted the use of conservative caries removal techniques (selective removal), but there is still controversy regarding its effectiveness. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified seven systematic reviews including seven studies overall, of which all were randomized trials. We concluded that selective caries removal may decrease the need for root canal treatment and the risk of pulp exposure in teeth with deep caries, but the certainty of the evidence is low. It is not clear whether the selective removal of caries reduces the risk of appearance of signs and symptoms of pulp disease and the risk of restorations failure, as the certainty of the evidence is very low.

Acidic calcium pools in intraerythrocytic malaria parasites.

Calcium uptake by permeabilized P. chabaudi malaria parasites was measured at the trophozoite stage to assess calcium accumulation by the parasite organelles. As determined with 45Ca2+, the total calcium in the parasite was found to be 11 pmoles/10(7) cells. When the K+/H+ uncoupling agent, nigericin was present, this level fell to 6.5 pmoles/10(7) cells. A similar regulatory mechanism operates in P. falciparum, since addition of nigericin to intact parasites in calcium free-medium resulted in a transient elevation of free calcium in the parasite cytosol, as judged by fluorescent imaging of single cells loaded with the calcium indicator fluo-3,AM. 7-Chloro-4-nitrobenz-2-oxa-1,3-diazole (NBD-Cl) and monensin, inhibitors of H+ ATPases and K+/H+ ionophore respectively, induced calcium elevation in fluo-3, AM-labeled intact P. chabaudi parasites. We conclude that malaria parasites utilize acidic intracellular compartments to regulate their cytosolic free calcium concentration.

Dengue epidemic in the State of Rio Grande do Norte, Brazil, in 1997.

During 1997 a large dengue epidemic occurred in Rio Grande do Norte, a State in north-east Brazil. The co-circulation of dengue virus type 1 and dengue virus type 2 was demonstrated by virus isolation in Aedes albopictus clone C6/36 cell-line and by reverse transcriptase-polymerase chain reaction (RT-PCR). IgM capture enzyme-linked immunosorbent assay confirmed 52.3% of the 8105 studied cases and dengue antigen was demonstrated by immunohistochemical reaction on hepatocytes from 2 out of 5 fatal cases studied. Individual risk factors for development of dengue haemorrhagic fever/dengue shock syndrome, such as hypertension, diabetes mellitus and bronchial asthma, are discussed.