Life cycle differences among Brazilian sandflies of the Lutzomyia longipalpis sibling species complex.

The developmental cycles of five Brazilian populations of the Lutzomyia longipalpis Lutz & Neiva species complex (Diptera: Psychodidae) were compared under laboratory conditions. Three of the populations were derived from insects collected in allopatric sites at Natal (Rio Grande do Norte State), Jacobina (Bahia State) and Lapinha Cave (Minas Gerais State). The other two originated from Sobral (Ceará State), where the males of two sympatric species can be distinguished by the presence of one (1S) or two (2S) pairs of abdominal spots. The results of the present study clearly show that all three populations whose males produce C16 pheromones and use pulse-type copulation songs (Jacobina, Lapinha Cave and Sobral 1S) are more easily adapted to the colonization conditions used in our laboratory, producing larger egg batches, with higher survival and an overall faster developmental cycle. This contrasts with populations producing C20 male pheromones and using burst-type copulation songs (Natal and Sobral 2S) that produce smaller egg batches, have higher oviposition mortality and a slower rate of development under identical laboratory conditions. In conclusion, these phenological differences are a further indication of the differentiation of the siblings within the Lu. longipalpis species complex.

Analysis of the activity patterns of two sympatric sandfly siblings of the Lutzomyia longipalpis species complex from Brazil.

Lutzomyia longipalpis s.l. (Lutz & Neiva) (Diptera: Psychodidae) is the main vector of visceral leishmaniasis in Latin America. Differences in copulation songs, pheromones and molecular markers show that L. longipalpis is a species complex in Brazil. The patterns of activity of insect vectors are important in disease transmission. In addition, differences in activity rhythms have a potential role as a temporal reproductive isolation mechanism in closely related species. We compared the activity patterns of males and females of two sympatric species of the Longipalpis complex from Sobral (Ceará State, Brazil) in controlled laboratory conditions. We observed small but significant differences between the two species in the activity phase in both males and females.

Genetic divergence between two sympatric species of the Lutzomyia longipalpis complex in the paralytic gene, a locus associated with insecticide resistance and lovesong production.

The sandfly Lutzomyia longipalpis s.l. is the main vector of American Visceral Leishmaniasis. L. longipalpis s.l. is a species complex but until recently the existence of cryptic sibling species among Brazilian populations was a controversial issue. A fragment of paralytic (para), a voltage dependent sodium channel gene associated with insecticide resistance and courtship song production in Drosophila, was isolated and used as a molecular marker to study the divergence between two sympatric siblings of the L. longipalpis complex from Sobral, Brazil. The results revealed para as the first single locus DNA marker presenting fixed differences between the two species in this locality. In addition, two low frequency amino-acid changes in an otherwise very conserved region of the channel were observed, raising the possibility that it might be associated with incipient resistance in this vector. To the best of our knowledge, the present study represents the first population genetics analysis of insecticide resistance genes in this important leishmaniasis vector.

Considerations on the effect of anti-sandfly antibodies on biological parameters of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae).

The immunization of vertebrate hosts with vector components may be an alternative for the control of diseases transmitted by insects. In the present study we evaluated the effects of anti-sandfly antibodies on some of the biological parameters of female Lutzomyia longipalpis, a vector of visceral leishmaniasis. Rabbits were immunized with extracts of gut from blood-fed (GB) or sugar-fed (GS) females, carcass of sugar-fed (CS) or blood-fed (CB) females, and with repeated sandfly bites (BITE). Immune sera showed increased antibody titers compared to pre-immunized animals, and specific bands were detected by Western Blot. An analysis of biological parameters revealed a decline in fecundity in the group of females fed on rabbits immunized with GB and BITE. Longevity and mortality were studied in females with oviposition (parous) and without oviposition (nulliparous). Nulliparous females that fed on rabbits immunized with bites died in the highest percentage. A mortality analysis after egg laying revealed a peak on the fifth day in all the groups, but females fed on rabbit subjected to repeated bites showed a shift towards the third day.

Phenotypic aspects of oral strains of Candida albicans in children with Down's syndrome.

The aim of this article is to characterize the biological aspects of oral strains of C. albicans in children with Down's syndrome. These yeasts were analyzed as to their macromorphological and enzymatic aspects and were tested as to their in vitro susceptibility to antifungal drugs using broth microdilution to determine the minimum inhibitory concentration (MIC). The morphotyping revealed that all oral C. albicans isolates from children with Down's syndrome promoted the formation of fringes regardless of size, while the control group presented smaller fringes. All oral C. albicans strains produced proteinase, but those with phospholipolytic activity showed greater enzyme capacity in the test group. In vitro susceptibility showed that all oral C. albicans isolates were sensitive to the drugs used.

New molecular markers for phlebotomine sand flies.

Using degenerate-primers PCR we isolated and sequenced fragments from the sand fly Lutzomyia longipalpis homologous to two behavioural genes in Drosophila, cacophony and period. In addition we identified a number of other gene fragments that show homology to genes previously cloned in Drosophila. A codon usage table for L. longipalpis based on these and other genes was calculated. These new molecular markers will be useful in population genetics and evolutionary studies in phlebotomine sand flies and in establishing a preliminary genetic map in these important leishmaniasis vectors.

Copulation songs in three siblings of Lutzomyia longipalpis (Diptera: Psychodidae).

We present the results of recording male courtship songs of the sandfly Lutzomyia longipalpis. The striking differences in the songs from 3 Brazilian populations of this sandfly with 3 distinct male pheromones support the 3 sibling species previously proposed based on this characteristic.

Assisted ventilation in neonates: the Manipal experience.

Case records of 68 newborns who required assisted ventilation over a 24 month period were reviewed. Fortyfour (64.7%) received intermittent mandatory ventilation, 10 (14.7%) received nasal CPAP and the remaining 14 (20.58%) received a combination of the above. Some of the indications for ventilation were infections (21), hyaline membrane disease (16), problems related to asphyxia (11), apnea of prematurity (10) and persistent pulmonary hypertension of newborn (5). The overall survival rate was 41.17%. In the CPAP group 90% (9/10) survived, while in the remaining survival was 32.7% (19/58). The best outcome was observed in persistent pulmonary hypertension of newborn (80%) followed by apnea of prematurity (70%) and hyaline membrane disease (43.75). Outcome was poor in conditions related to birth asphyxia (27.2%) and infections (19.05%). Survival rates were higher (44.4%) in babies weighing > 1500g at birth as compared to 40.9% in babies < 1500g. Babies less than 32 weeks gestation had a survival rate of 32% as compared to 46.5% in those over 32 weeks. This difference was not statistically significant. Complications were seen in 12/68 patients (17.6%). Pneumothorax was the commonest followed by sepsis, intraventricular hemorrhage and blocked endotracheal tubes. Babies with hyaline membrane disease had the highest incidence of complications. Analysis of the data with regard to the indications, outcome and complications is presented.

[Nursing: the integrated curriculum in the evaluation and perception of the nursing faculty]. / Enfermagem: o currículo integrado na avaliação e percepção dos docentes.

The following study aims at determining the perspectives and difficulties experienced by the teaching staff of the Nursing Department at the Health Sciences Center in Londrina State University during the development and implementation of Module I of their integrated curriculum. The research was constituted by a case study and data were obtained from a set of questions posed to 13 (thirteen) teachers who designed and implemented the Module I of the integrated curriculum at the nursing school in Londrina State University, during the year of 2000. The analysis of the data allowed the authors to determine those factors which either made it difficult or facilitated the process implementation, as well as to raise teachers' perception about the process of curricular change. The study, by supplying indicatives of change, contributes to the improvement of the quality of nursing education as the new curriculum is implemented at Londrina State University.

Pullout bond strength of fiber posts luted to different depths and submitted to artificial aging.

INTRODUCTION: The extension of fiber post cementation often does not seem to influence the fracture resistance of restorations. This study evaluated the effects of cementation depths on the retention of fiber posts submitted to artificial aging. METHODS: One hundred and sixty bovine incisors were selected to assess post retention. Following endodontic treatment, the canals were flared with diamonds burs. Postholes were prepared in lengths of 5 or 10 mm, after which fiber posts were relined with composite resin and luted with RelyX ARC or RelyX Unicem. The samples were then submitted to thermal and/or mechanical cycling before testing their pullout bond strengths. Absence of cycling was used as a control. The results of each cement were submitted to two-way and post hoc Tukey tests (α=0.05). RESULTS: Independent of the aging protocol, a depth of 10 mm showed higher pullout bond strength than did 5 mm, except for RelyX Unicem without cycling. For RelyX ARC, thermomechanical cycling resulted in lower values than in the absence of cycling. Mechanical cycling alone promoted the highest bond strength when the posts were luted with RelyX Unicem. CONCLUSION: The effect of artificial aging on the pullout bond strength is dependent on the type of material and the depth.

Diatom assemblages promote ice formation in large lakes.

We present evidence for the directed formation of ice by planktonic communities dominated by filamentous diatoms sampled from the ice-covered Laurentian Great Lakes. We hypothesize that ice formation promotes attachment of these non-motile phytoplankton to overlying ice, thereby maintaining a favorable position for the diatoms in the photic zone. However, it is unclear whether the diatoms themselves are responsible for ice nucleation. Scanning electron microscopy revealed associations of bacterial epiphytes with the dominant diatoms of the phytoplankton assemblage, and bacteria isolated from the phytoplankton showed elevated temperatures of crystallization (T(c)) as high as -3 °C. Ice nucleation-active bacteria were identified as belonging to the genus Pseudomonas, but we could not demonstrate that they were sufficiently abundant to incite the observed freezing. Regardless of the source of ice nucleation activity, the resulting production of frazil ice may provide a means for the diatoms to be recruited to the overlying lake ice, thereby increasing their fitness. Bacterial epiphytes are likewise expected to benefit from their association with the diatoms as recipients of organic carbon excreted by their hosts. This novel mechanism illuminates a previously undescribed stage of the life cycle of the meroplanktonic diatoms that bloom in Lake Erie and other Great Lakes during winter and offers a model relevant to aquatic ecosystems having seasonal ice cover around the world.

Neuromyelitis optica in Brazil: a study on clinical and prognostic factors.

OBJECTIVES: To describe the clinical characteristics of patients with relapsing neuromyelitis optica (NMO) from a tertiary care center in Brazil and compare the groups with normal and abnormal brain magnetic resonance imaging (MRI). METHODS: Retrospective review of 41 patients followed at the Neuroimmunology Clinic of the Federal University of São Paulo, Brazil, from 1994 to 2007. RESULTS: All patients had relapsing-remitting optic-spinal disease, long extending spinal cord lesions, and brain MRI not meeting Barkhof criteria for multiple sclerosis (MS), thus fulfilling the 1999 and 2006 Wingerchuck criteria for NMO. Mean follow-up time was 52 months; mean age of onset was 32.6 years. The mean relapse rate (RR) and progression index (PI) were 1.0 and 0.9, respectively. Twenty-four patients had brain lesions not compatible with MS on MRI, and there were no statistical differences on PI and RR between patients who had brain lesions and patients who did not. Incomplete recovery, but not the type of first relapse, correlated with a worse prognosis. Seventeen patients were tested for NMO-IgG (anti-aquaporin-4 antibody) with 41% positivity. CONCLUSIONS: In this series, we did not find a statistical difference of disease progression between patients with and without brain lesions, suggesting that the presence of brain abnormalities is not a marker of disease severity.

[Natural infection of Lutzomyia intermedia Lutz & Neiva, 1912, in an endemic area of visceral leishmaniasis of Rio de Janeiro]. / Infeccão natural de Lutzomyia intermedia Lutz & Neiva, 1912, em área endemica de leishmaniose tegumentar no Estado do Rio de Janeiro.

In a focus of cutaneous leishmaniasis in Jacarepaguá, Rio de Janeiro, one specimen of Lutzomyia intermedia was found naturally infected with Leishmania braziliensis.

[Establishment of a colony, in laboratory, of Lutzomyia intermedia Lutz & Neiva, 1912 (Diptera, Psychodidae, Phlebotominae)]. / Estabelecimento de colônia, em laboratório, de Lutzomyia intermedia Lutz & Neiva, 1912 (Diptera, Psychodidae), Phlebotominae).

A laboratory colony of the sandfly Lutzomyia intermedia was established (at present in its seventh generation) in order to provide specimens for experimental infection and for experimental xenodiagnosis of natural infections due to cutaneous leishmanias in Rio de Janeiro. Date are presented on the methodology and on the yield and duration of each stage of development, during the first four generations.

The Phlebotominae sand fly (Diptera: Psychodidae) fauna of two Atlantic Rain Forest Reserves in the State of Rio de Janeiro, Brazil.

During two consecutive years, studies on the sand fly fauna in Poço das Antas and Fazenda Bom Retiro, two Atlantic Rain Forest Reserves from the State of Rio de Janeiro, were performed using Shannon traps, CDC light traps and human bait collections. Eleven species were identified; Lutzomyia longipalpis, L. migonei, L. edwardsi, L. intermedia, L. whitmani, L. fischeri, L. shannoni, L. ayrozai, L. hirsuta, L. monticola and L. misionensis (first occurrence in the State of Rio de Janeiro). L. intermedia and L. whitmani were the predominant anthropophilic species around houses, while L. hirsuta predominated in the forest.

Studies on sandfly fauna (Diptera: Psychodidae) in a foci of cutaneous leishmaniasis in mesquita, Rio de Janeiro State, Brazil.

In a study on vectors of cutaneous leishmaniasis in Mesquita, Rio de Janeiro State, Brazil, eleven species of sandflies were found: Lutzomyia longipalpis, L. fischeri, L. quinquefer, L. intermedia, L. whitmani, L. shannoni, L. cortelezzii, L. edwardsi, L. migonei, L. lanei and L. firmatoi. Lutzomyia intermedia was the predominant species. It was collected indoors but in much higher numbers outdoors, in the close vicinity of houses. In comparative captures it was found to feed more frequently on equines, and less frequently on man and dogs. Studies, using man and animals as baits, showed that blood-feeding started in the evening, and remained stable during the night, until early morning. June, August and October were the months of highest density.

[Phlebotomus of Vargem Grande, a focus of cutaneous leishmaniasis in the State of Rio de Janeiro]. / Flebótomos de Vargem Grande, foco de leishmaniose tegumentar no Estado do Rio de Janeiro.

In Vargem Grande, an endemic area of cutaneous leishmaniasis in State of Rio de Janeiro, where Lutzomyia intermedia had been found infected with Leishmania braziliensis, we performed a series of captures of sandflies to increase the knowledge on their behaviour. The following species were found among 8,671 sandflies collected: L. intermedia, L. migonei, L. longipalpis, L. lanei, L. fischeri, L. firmatoi, L. monticola, L. schreiberi, L. whitmani, L. pelloni, L. barrettoi e L. (Pi) sp. Inside houses and outdoors close to the houses, on human bait and in light traps, the predominant species was L. intermedia, followed by L. migonei, both being more numerous between 9 and 11 p.m. than from 6 to 8 p.m. In a plantation, L. migonei was predominant. In simultaneous captures on man and dog as baits, L. intermedia was more frequent on the former, L. migonei on the latter.