Clinical and epidemiological aspects of human parvovirus B19 infection in an urban area in Brazil (Niterói city area,State of Rio de Janeiro,Brazil)

This study was designed to analyse the clinical and epidemiological data from human parvovirus B19 cases in a six-year study of rash diseases conduct in an urban area in Brazil (Niterói city area, State of Rio de Janeiro). A total of 673 patients with acute rash diseases were seen at two primary health care units and at a general hospital. A clotted blood sample was collected from all subjects at the time of consultation. Forty-nine per cent (330 cases) of the patients were negative for dengue, rubella and measles IgM or for low avidity IgG to HHV-6. Of these 330, 105 (31.8%) were identified as IgM positive to parvovirus B19 by using an antibody capture EIA. During the study period, three distinct peaks of parvovirus infection were detected, suggesting that the disease appears to cycle in approximately 4-5 years. B19 infection was characterized by variable combinations of fever, flu-like symptoms, arthropathy, and gastrointestinal symptoms. Frequency of fever and arthropathy was substantially higher in adults, 75% [chi2 (1 D.F.) = 11.39, p = 0.0007] and 62.5% [chi2 (1 D.F.) = 29.89, p = 0.0000], respectively. "Slapped-cheek" appearance and reticular or lace-like rash were seen in only 30.1% of the children. No adult presented this typical rash. The lack of the typical rash pattern in a large proportion of parvovirus B19 and the similarity of clinical manifestations to other rash diseases, specially to rubella, highlight the difficulty of diagnosing B19 infection on clinical grounds alone.     

Seroepidemiological study of herpes simplex virus type 2 in patients with the acquired immunodeficiency syndrome in the city of Niterói, Rio de Janeiro, Brazil

This study was designed to determine the seroprevalence of herpes simplex virus type 2 (HSV-2) and to evaluate its association with age, sex as well as other demographic and behavioural factors in 150 human immunodeficiency virus (HIV) positive adults patients attending the general medical outpatient ward for routine care of Niterói, state of Rio de Janeiro, Brazil. Serum samples were screened for HSV-2 antibodies using an indirect ELISA. Eighty-three patients were men (mean age: 38.8) and 67 were women (mean age: 35.4). The estimated prevalence of HSV-2 was 52% (95% CI: 44-60%) and it was higher among men (53%) than among women (50.7%). Overall, the age of first sexual intercourse and past history of genital herpes were associated with HSV-2 seropositivity. Analysis by gender disclosed significant association of number of lifetime sex partners only among men. Although HSV-2 antibodies were frequent in the study group, genital herpes was reported by 21.8% of the HSV-2 positive subjects, indicating low awareness of the HSV-2 infection. These results may have public health importance for Brazil as the high rate of HSV-2 infection may act as a cofactor of HIV transmission.     

Source of Chagas disease in Arcádia, state of Rio de Janeiro, Brazil

Following the report of triatomine nymphs in a house in Arcadia, Miguel Pereira, state of Rio de Janeiro, Brazil, the infested dwelling was checked. Several eggs and 46 specimens of Triatoma vitticeps (Stal, 1859) were collected. Among them, adults and nymphal instars accounted for 43.5% and 56.5%, respectively. Analysis of blood meals showed the ecletism of this species; 24 (52.2%) were single feeds, 18 insects (39.1%) fed on two hosts and 4 (8.7%) on three hosts. Trypanosoma cruzi infection rate of examined specimens was 13%. Finally one of the residents of the house was positive for anti-T. cruzi antibodies using indirect immunofluorescence.     

Trypanosoma cruzi infection in Leontopithecus rosalia at the Reserva Biológica de Poco das Antas, Rio de Janeiro, Brazil

Wild golden lion tamarins (Leontopithecus rosalia) - endangered primates that are native to the Brazilian Atlantic coastal forest - were surveyed for the presence of Trypanosoma cruzi with the use of Giemsa-stained blood smears, hemocultures and an indirect immunofluorescence assay (IFAT). Positive IFAT with titers ranging from 1:20 to 1:1280 were observed in 52% of the 118 wild tamarins examined and the parasite was isolated from 38 tamarins. No patent parasitemia was observed among the tamarins from which T. cruzi was isolated. Serum conversion and positive hemoculture was observed for three animals that had yielded negative results some months earlier, which indicates that T. cruzi is actively transmitted among tamarins. In contrast to observations with other sylvatic isolates, those from the tamarins were significantly more virulent and most of them produced mortality in experimentally infected Swiss mice. Some variation in the kDNA restriction profiles among the isolates was observed. Electrophoresis with GPI, G6PDH, IDH, MDH and ME enzymes showed a Z2 profile.     

Paleogenetic and taphonomic analysis of human bones from Moa, Beirada, and Zé Espinho Sambaquis, Rio de Janeiro, Brazil

The present paper discusses mtDNA and taphonomy of human remains from Moa, Beirada, and Zé Espinho sambaquis of Saquarema, state of Rio de Janeiro, Brazil. New human bone dating by 14C-AMS for Moa archeological site (3810+50 BP - GX-31826-AMS) is included. Preservation of microscopic lamellae and DNA is not related to the macroscopic integrity of the bones. Results here suggest that the preservation of amplifiable DNA fragments may have relation to the preservation of the lamellar arrangement as indicated by optical microscopic examination (polarized light). In 13 human bone fragments from Moa, Beirada, and Zé Espinho it was possible to sequence mtDNA from the 3 individuals of Moa, and from 1 of 4 individuals of Beirada, whose bones also show extensive areas with preserved lamellar structures. The 6 human bone fragments of Zé Espinho and 3 of the 4 fragments of Beirada showed extensive destruction of cortical microstructure represented by cavities, intrusive minerals, and agglomerated microscopic bodies of fungi and bacteria; it was not possible to extract mtDNA from these samples. The results support the hypothesis that the preservation of the microscopic osteon organization is a good predictor for DNA preservation. It was also confirmed the C haplogroup antiquity in Brazil.     

Susceptibility of six Arabic coffee cultivars to fruit flies (Diptera: Tephritoidea) under shaded and unshaded organic management in Valença, State of Rio de Janeiro, Brazil

The infestation indices by fruit flies were determined for six cultivars of Coffea arabica L. in shaded and unshaded systems under organic management. The experiment was set in a completely randomized design with a split-split-plot arrangement and four replicates. A 250g-sample of maturing fruits per plot was harvested in May 2005. The cultivars Icatu Amarelo and Catucaí Amarelo were the least susceptible to attack by tephritids in both systems. As for lonchaeids, Oeiras, Catucaí Amarelo and Catuaí Vermelho were the least susceptible cultivars in the shaded system, and there was no difference among the cultivars in the unshaded system. The following tephritid species were obtained: Ceratitis capitata (Wiedemann), Anastrepha fraterculus (Wiedemann) and A. sororcula Zucchi (Tephritidae). Lonchaeids were represented by Neosilba bifida Strikis & Prado, N. certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. pseudopendula (Korytkowski and Ojeda), Dasiops rugifrons Hennig, Neosilba n.sp.10 and Neosilba n.sp.14.     

Species of Lutzomyia França (Diptera: Psychodidae, Phlebotominae) in area with Cutaneous Leishmaniasis case of Carmo County, Rio de Janeiro State, Brazil

Captures of sand flies were carried out in peridomiciliary, domiciliary and forest environments on S?o José farm, located in Carmo county where an autochthonous case of American Cutaneous Leishmaniasis occurred to investigate the probable vector of the disease. A total of 4.595 sand flies belonging to six species of the genus Lutzomyia were captured: L. intermedia (Lutz & Neiva), L. lenti (Mangabeira), L. whitmani (Antunes & Coutinho) L. migonei (Fran?a), L. ayrozai (Barretto & Coutinho) andL. quinquefer (Dyar). L. intermedia was the predominant species (99.1%), its highest frequencies occurring between 6 p.m. and 8 p.m.     

T-cell receptor Vβ repertoire of CD8+ T-lymphocyte subpopulations in cutaneous leishmaniasis patients from the state of Rio de Janeiro, Brazil

In human cutaneous leishmaniasis (CL), the immune response is mainly mediated byT-cells. The role of CD8⁺ T-lymphocytes, which are related to healing ordeleterious functions, in affecting clinical outcome is controversial. The aim ofthis study was to evaluate T-cell receptor diversity in late-differentiated effector(LDE) and memory CD8⁺ T-cell subsets in order to create a profile ofspecific clones engaged in deleterious or protective CL immune responses. Healthysubjects, patients with active disease (PAD) and clinically cured patients wereenrolled in the study. Total CD8⁺ T-lymphocytes showed a disturbance inthe expression of the Vβ2, Vβ9, Vβ13.2, Vβ18 and Vβ23 families. The analyses ofCD8⁺T-lymphocyte subsets showed high frequencies of LDECD8⁺T-lymphocytes expressing Vβ12 and Vβ22 in PAD, as well aseffector-memory CD8⁺ T-cells expressing Vβ22. We also observed lowfrequencies of effector and central-memory CD8⁺ T-cells expressing Vβ2 inPAD, which correlated with a greater lesion size. Particular Vβ expansions point toCD8⁺ T-cell clones that are selected during CL immune responses,suggesting that CD8⁺ T-lymphocytes expressing Vβ12 or Vβ22 are involved ina LDE response and that Vβ2 contractions in memory CD8⁺T-cells areassociated with larger lesions.     

Stability evaluation and sensitive determination of antiviral drug,valacyclovir and its metabolite acyclovir in human plasma by a rapid liquid chromatography–tandem mass spectrometry method

A simple, sensitive and high throughput liquid chromatography/positive-ion electrospray ionization mass spectrometry (LC–ESI-MS/MS) method has been developed for the simultaneous determination of valacyclovir and acyclovir in human plasma using fluconazole as internal standard (IS). The method involved solid phase extraction of the analytes and IS from 0.5 mL human plasma with no reconstitution and drying steps (direct injection of eluate). The chromatographic separation was achieved on a Gemini C18 analytical column using isocratic mobile phase, consisting of 0.1% formic acid and methanol (30:70 v/v), at a flow-rate of 0.8 mL/min. The precursor → product ion transition for valacyclovir (m/z 325.2 → 152.2), acyclovir (m/z 226.2 → 152.2) and IS (m/z 307.1 → 220.3) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) mode. The method was validated over the concentration range 5.0–1075 ng/mL and 47.6–10225 ng/mL for valacyclovir and acyclovir respectively. The mean recovery of valacyclovir (92.2%), acyclovir (84.2%) and IS (103.7%) from spiked plasma samples was consistent and reproducible. The bench top stability of valacyclovir and acyclovir was extensively evaluated in buffered and unbuffered plasma. It was successfully applied to a bioequivalence study in 41 healthy human subjects after oral administration of 1000 mg valacyclovir tablet formulation under fasting condition.     

Ecological aspects of phlebotomus of the Parque Nacional da Serra dos Org?os, Rio de Janeiro. I. Monthly frequency in human baits (Diptera, Psychodidae, Phlebotominae)

During two full years--from October 1980 to September 1982--we captured sandflies in the National Park of Serra dos Org?os, State of Rio de Janeiro, Brazil. The captures, with human bait, were carried out weekly, each with a duration of two hours, and at three different times (6 to 8 a.m., 5 to 7 a.m. and 7:30 to 9:30 p.m.). In every capture, we recorded the phase of the moon and, at each hour, the temperature, relative humidity, wind and rain. In 586 hours 4,834 sandflies of ten species were captured, all belonging to genus Lutzomyia Fran?a, 1924. L. ayrozai and L. hirsuta represented 92% of the total species captured. However, they were dominant at different times, the former being more frequent in the warm and wet months, and considerably declining in the cold and dry months, in which the latter gradually prevailed. L. fischeri and L. shannoni were shown to be the most resistant to unfavourable weather conditions. Whenever there was any rain or wind, they were, in general, the only species captured. With regard to lunar cycle, we observed that new moon was the most favourable phase for the capture of sandflies and full moon the one with the smallest yield, except for L. shannoni which occurred more frequently during this period.     

Angiostrongylus cantonensis infection in molluscs in the municipality of S?o Gon?alo,a metropolitan area of Rio de Janeiro,Brazil: role of the invasive species Achatina fulica in parasite transmission dynamics

The aim of this study was to analyse the infection dynamics ofAngiostrongylus cantonensis in its possible intermediate hosts over two years in an urban area in the state of Rio de Janeiro where the presence ofA. cantonensis had been previously recorded in molluscs. Four of the seven mollusc species found in the study were exotic.Bradybaena similaris was the most abundant, followed byAchatina fulica, Streptaxis sp., Subulina octona, Bulimulus tenuissimus, Sarasinula linguaeformis and Leptinaria unilamellata. Only A. fulica and B. similaris were parasitised by A. cantonensis and both presented co-infection with other helminths. The prevalence of A. cantonensisin A. fulica was more than 50% throughout the study. There was an inverse correlation between the population size ofA. fulica and the prevalence of A. cantonensis and abundance of the latter was negatively related to rainfall. The overall prevalence of A. cantonensis in B. similariswas 24.6%. A. fulica was the most important intermediary host of A. cantonensis in the studied area andB. similaris was secondary in importance for A. cantonensis transmission dynamics.     

Development of a cell-based screening method for compounds that inhibit or are transported by large neutral amino acid transporter 1, a key transporter at the blood–brain barrier

Large neutral amino acid transporter 1 (LAT1) transports neutral amino acids with aromatic or branched side chains as well as their derivatives or prodrugs. Because the transporter is highly expressed at the blood–brain barrier and in some tumor cells, it is a potential target to treat brain disease and cancer. Therefore, it is essential to develop a method to screen for LAT1 inhibitors or for therapeutic compounds that it can transport. In this study, one such method was developed that combines an in vitro cell-based assay with high-throughput ultra-performance liquid chromatography triple quadrupole mass spectrometry (UPLC–QQQ–MS). Using this method, candidate compounds could be tested for the ability to inhibit or to compete with uptake of gabapentin, an LAT1 substrate, in HT-29 cells, which abundantly express the transporter. Gabapentin uptake is measured by mass spectrometry, which requires as little as 6 min/sample and will enable analysis of large numbers of samples. We anticipate that the method will be useful to identify LAT1 inhibitors or substrates without the need for animals or radioactive labeling.     

Hemilucilia segmentaria (Fabricius, 1805) (Diptera: Calliphoridae) as new biological vector of eggs of Dermatobia hominis (Linnaeus Jr., 1781) (Diptera: Oestridae) in Reserva Biológica do Tinguá, Rio de Janeiro, Brazil

The aim of this note was to record for the first time the finding of Hemilucilia segmentaria acting as biological vector of Dermatobia hominis, during a study of the diversity of Calliphoridae at Reserva Biol gica do Tinguá, Rio de Janeiro, Brazil. The insects were captured using traps baited with chicken vicera, for a period of 28-30 h twice per month. In the period of one year, 1987 insects were collected, 7.5% of which belonged to the H. segmentaria; of these a female was captured in May 2001, carrying a mass of 20 eggs on the left side of its abdomen.     

Tautomerization of 2-nitroso-N-arylanilines by coordination as N,N′-chelate ligands to rhenium(i) complexes and the anticancer activity of newly synthesized oximine rhenium(i) complexes against human melanoma and leukemia cells in vitro

The synthesis, structural characterization and biological activity of eight ortho-quinone(N-aryl)-oximine rhenium(i) complexes are described. The reaction of the halogenido complexes (CO)₅ReX (X=Cl (4), Br (5)) with 2-nitroso-N-arylanilines {(C₆H₃ClNO)NH(C₆H₄R)} (R = p-Cl, p-Me, o-Cl, H) (3a–d) in tetrahydrofurane (THF) yields the complexes fac-(CO)₃XRe{(C₆H₃ClNO)NH(C₆H₄R)} (6a–d, 7a–d) with the tautomerized ligand acting as a N,N′-chelate. The substitution of two carbonyl ligands leads to the formation of a nearly planar 5-membered metallacycle. During coordination the amino-proton is shifted to the oxygen of the nitroso group which can be observed in solution for 6 and 7 by ¹H NMR spectroscopy and in solid state by crystal structure analysis. After purification, all compounds have been fully characterized by their ¹H and ¹³C NMR, IR, UV/visible (UV/Vis) and mass spectra. The X-ray structure analyses revealed a distorted octahedral coordination of the CO, X and N,N′-chelating ligands for all Re(i) complexes. Biological activity of four oximine rhenium(i) complexes was assessed in vitro in two highly aggressive cancer cell lines: human metastatic melanoma A375 and human chronic myelogenous leukemia K562. Chlorido complexes (6a and 6c) were more efficient than bromido compounds (7d and 7b) in inducing apoptotic cell death of both types of cancer cells. Melanoma cells were more susceptible to tested rhenium(i) complexes than leukemia cells. None of the ligands (3a–d) showed any significant anticancer activity.     

Late Quaternary grassland (Campos), gallery forest,fire and climate dynamics,studied by pollen,charcoal and multivariate analysis of the São Francisco de Assis core in western Rio Grande do Sul (southern Brazil)

We present a detailed pollen and charcoal record of a 368-cm-long sediment core from the lowland Campos (grassland) region near the city of São Francisco de Assis in the western Rio Grande do Sul State in southern Brazil. Based on four AMS radiocarbon dates, the record represents the last about 22,000 cal yr BP. The region was naturally covered by Campos throughout the recorded glacial and Holocene period under cold and relatively dry and warm and dry condition, respectively. Initial expansion of gallery forest after 5170 cal yr BP indicates a change to wetter climatic conditions. Maximum extent of gallery forest after 1550 cal yr BP reflects the wettest recorded period. There is some evidence of plant migration from the eastern Atlantic coastal lowland reaching the western lowland, first after mid Holocene times by Cecropia and, possibly, species of Myrsine and Moraceae and later, after about 1000 cal yr BP, by species of Alchornea and Acalypha. Multivariate analysis revealed that the long-term pollen composition dynamics is a two-phase process, with random, chaotic changes characterizing some periods when climate conditions were likely more stable, and directional compositional changes (phase transitions) in periods coincide with major climate and/or anthropogenic changes. Natural fires were rare during full- and lateglacial periods, but became frequent at the beginning of the Holocene, suggesting the beginning of human occupation of the western lowland at that time. Highest fire frequency is found during the wet late Holocene period, suggesting an increase of indigenous populations in the São Francisco de Assis region.