The maternal 14 bp Ins/Del polymorphism in HLA-G is not associated with preeclampsia risk.

The effect of HLA-G 14 bp Ins/Del polymorphism (rs371194629) on the risk of preeclampsia has been assessed in several populations, yet the results are still conflicting. Lack of power due to small sample sizes is a common cause of inconsistencies in genetic association studies. We aimed to test whether the maternal polymorphism is associated with preeclampsia, eclampsia or HELLP syndrome (acronym for Hemolysis, Elevation of Liver enzymes, Low Platelets). To achieve a statistical power greater than 0.90, a total of 741 women (332 controls, 246 preeclampsia, 57 eclampsia and 106 HELLP) were genotyped for the 14-bp Ins/Del polymorphism. The genetic association with disease status was assessed by Fisher's exact test and odds ratio (OR) estimates using logistic regression model adjusted for maternal age and parity status. Allele and genotype distributions were the same between control and case groups (p > .05). The polymorphism was not associated with the risk of developing preeclampsia [OR = 0.93 (0.72-1.19); p = .541], or eclampsia [OR = 0.90 (0.60-1.38); p = .628] nor HELLP syndrome [OR = 0.92 (0.66-1.28); p = .628]. This well-powered study clearly demonstrates that the maternal HLA-G 14-bp Ins/Del polymorphism is not associated with preeclampsia risk. However, as the offspring genotypes were not evaluated here, we could not rule out the effect of the foetal genotype on the preeclampsia pathogenesis.

Comparative analyses of whole genome sequences of Leishmania infantum isolates from humans and dogs in northeastern Brazil.

The genomic sequences of 20 Leishmania infantum isolates collected in northeastern Brazil were compared with each other and with the available genomic sequences of 29 L. infantum/donovani isolates from Nepal and Turkey. The Brazilian isolates were obtained in the early 1990s or since 2009 from patients with visceral or non-ulcerating cutaneous leishmaniasis, asymptomatic humans, or dogs with visceral leishmaniasis. Two isolates were from the blood and bone marrow of the same visceral leishmaniasis patient. All 20 genomic sequences display 99.95% identity with each other and slightly less identity with a reference L. infantum genome from a Spanish isolate. Despite the high identity, analysis of individual differences among the 32 million base pair genomes showed sufficient variation to allow the isolates to be clustered based on the primary sequence. A major source of variation detected was in chromosome somy, with only four of the 36 chromosomes being predominantly disomic in all 49 isolates examined. In contrast, chromosome 31 was predominantly tetrasomic/pentasomic, consistent with its regions of synteny on two different disomic chromosomes of Trypanosoma brucei. In the Brazilian isolates, evidence for recombination was detected in 27 of the 36 chromosomes. Clustering analyses suggested two populations, in which two of the five older isolates from the 1990s clustered with a majority of recent isolates. Overall the analyses do not suggest individual sequence variants account for differences in clinical outcome or adaptation to different hosts. For the first known time, DNA of isolates from asymptomatic subjects were sequenced. Of interest, these displayed lower diversity than isolates from symptomatic subjects, an observation that deserves further investigation with additional isolates from asymptomatic subjects.

D2 dopamine receptor regulation of learning, sleep and plasticity.

Dopamine and sleep have been independently linked with hippocampus-dependent learning. Since D2 dopaminergic transmission is required for the occurrence of rapid-eye-movement (REM) sleep, it is possible that dopamine affects learning by way of changes in post-acquisition REM sleep. To investigate this hypothesis, we first assessed whether D2 dopaminergic modulation in mice affects novel object preference, a hippocampus-dependent task. Animals trained in the dark period, when sleep is reduced, did not improve significantly in performance when tested 24h after training. In contrast, animals trained in the sleep-rich light period showed significant learning after 24h. When injected with the D2 inverse agonist haloperidol immediately after the exploration of novel objects, animals trained in the light period showed reduced novelty preference upon retesting 24h later. Next we investigated whether haloperidol affected the protein levels of plasticity factors shown to be up-regulated in an experience-dependent manner during REM sleep. Haloperidol decreased post-exploration hippocampal protein levels at 3h, 6h and 12h for phosphorylated Ca(2+)/calmodulin-dependent protein kinase II, at 6h for Zif-268; and at 12h for the brain-derived neurotrophic factor. Electrophysiological and kinematic recordings showed a significant decrease in the amount of REM sleep following haloperidol injection, while slow-wave sleep remained unaltered. Importantly, REM sleep decrease across animals was strongly correlated with deficits in novelty preference (Rho=0.56, p=0.012). Altogether, the results suggest that the dopaminergic regulation of REM sleep affects learning by modulating post-training levels of calcium-dependent plasticity factors.

Association between ACVR2A and early-onset preeclampsia: replication study in a Northeastern Brazilian population.

INTRODUCTION: Preeclampsia is a complex and heterogeneous disease with increased risk of maternal mortality, especially for earlier gestational onset. There is a great inconsistency regarding the genetics of preeclampsia across the literature. The gene Activin A receptor, type IIA (ACVR2A), was reported as associated to preeclampsia in Australian/New Zealand and Norwegian populations. The goal of this study was to validate this genetic association in a Brazilian population. METHODS: We performed a case-control study using 693 controls and 613 cases (443 preeclampsia, 64 eclampsia and 106 HELLP syndrome), from a Northeastern Brazilian population. Five single nucleotide polymorphisms (SNPs) in ACVR2A were tested for association through multiple logistic regression models. RESULTS: There was no statistical association with preeclampsia (per se), eclampsia or HELLP. However, by grouping preeclampsia in accordance to the gestational age at delivery, SNPs rs1424954 (OR = 1.86; 95% CI, 1.25-2.78; p = 0.002) and rs1014064 (OR = 1.77; 95% CI, 1.21-2.60; p = 0.004) were significantly associated with early onset preeclampsia (gestational age ≤ 34 weeks). The risk haplotype had a frequency of 0.468 in early preeclampsia compared to 0.316 in controls (p = 0.0008 and permuted p = 0.002). DISCUSSION: Activin A receptors are important in decidualization, trophoblast invasion and placentation processes during pregnancy. The gene ACVR2A was associated with the more severe early onset preeclampsia. This finding supports the hypothesis of different pathogenic mechanisms contributing to the early- and late-onset preeclampsia.

Clinical characteristics of Guillain-Barré syndrome in a tropical country: a Brazilian experience.

OBJECTIVE: To analyze the clinical variants, outcomes, and prognosis of Guillain-Barré syndrome (GBS) in a Brazilian population. MATERIALS AND METHODS: Clinical and laboratory data of 149 cases of GBS diagnosed from 1994 to 2007 were analyzed. RESULTS: Acute inflammatory demyelinating polyneuropathy (AIDP) was the most frequent variant (81.8%) of GBS, followed by acute motor axonal neuropathy (AMAN) (14.7%) and acute motor and sensory axonal neuropathy (AMSAN) (3.3%). The incidence of GBS was 0.3/100,000 for the state of Rio Grande do Norte and cases occurred at a younger age. GBS was preceded by infections, with the axonal variant associated with episodes of diarrheas (P = 0.025). Proximal weakness was more frequent in AIDP, and distal weakness predominant in the axonal variant. Compared to 42.4% of cases with AIDP (P < 0.0001), 84.6% of cases with the axonal variant had nadir in <10 days. Individuals with the axonal variant took longer to recover deambulation (P < 0.0001). The mortality of GBS was 5.3%. CONCLUSION: A predominance of the AIDP variant was seen, and the incidence of the disease decreased with age. As expected, the distribution of weakness correlated with the clinical variants, and individuals with the axonal variant had a poorer prognosis.

The emergence of concurrent HIV-1/AIDS and visceral leishmaniasis in Northeast Brazil.

HIV has become increasingly prevalent in the Northeast region of Brazil where Leishmania infantum chagasi is endemic, and concurrent AIDS and visceral leishmaniasis (VL) has emerged. In this study, persons with HIV/AIDS and VL (n=17) had a mean age of 37.3 years (range 29-53 years) compared with 12.5 years (1-80 years) for persons with VL alone (n=2836). Males accounted for 88% of cases with concurrent VL and AIDS and 65% of those with VL alone. The mean CD4 count and antileishmanial antibody titre were lower and recurrence of VL and death were more likely with co-infection. Considering the prevalences of L.i. chagasi and HIV in the region, this may herald the emergence of an important public health problem.

Genes at human chromosome 5q31.1 regulate delayed-type hypersensitivity responses associated with Leishmania chagasi infection.

Visceral leishmaniasis (VL) caused by Leishmania chagasi is endemic to northeast Brazil. A positive delayed-type hypersensitivity skin test response (DTH+) is a marker for acquired resistance to disease, clusters in families and may be genetically controlled. Twenty-three single nucleotide polymorphisms (SNPs) were genotyped in the cytokine 5q23.3-q31.1 region IRF1-IL5-IL13-IL4-IL9-LECT2-TGFBI in 102 families (323 DTH+; 190 DTH-; 123 VL individuals) from a VL endemic region in northeast Brazil. Data from 20 SNPs were analyzed for association with DTH+/- status and VL using family-based, stepwise conditional logistic regression analysis. Independent associations were observed between the DTH+ phenotype and markers in separate linkage disequilibrium blocks in LECT2 (OR 2.25; P=0.005; 95% CI=1.28-3.97) and TGFBI (OR 1.94; P=0.003; 95% CI=1.24-3.03). VL child/parent trios gave no evidence of association, but the DTH- phenotype was associated with SNP rs2070874 at IL4 (OR 3.14; P=0.006; 95% CI=1.38-7.14), and SNP rs30740 between LECT2 and TGFBI (OR 3.00; P=0.042; 95% CI=1.04-8.65). These results indicate several genes in the immune response gene cluster at 5q23.3-q31.1 influence outcomes of L. chagasi infection in this region of Brazil.

Serum markers of rheumatoid arthritis in visceral leishmaniasis: rheumatoid factor and anti-cyclic citrullinated peptide antibody.

Rheumatoid factor (RF) has been described in visceral leishmaniasis (VL). However, there is no report of RF-isotype or other rheumatoid arthritis (RA) autoantibody in VL. This work investigated RF and anti-cyclic citrullinated peptide antibody (CCP-Ab) in sera from 35 inhabitants from a VL area: 15 from healthy persons (HIEA); 10 from VL patients (VL), and 10 from subjects cured of VL (CVL). The controls were represented by sera from 15 healthy individuals (HI) and from 10 RA patients from a VL free area. IgM-RF was investigated by immunoturbidimetry, while IgA-RF and CCP-Ab by enzyme-linked immunosorbent assay (ELISA). Increased RF-IgM production was found in 9 out of 10 sera from both VL and RA groups (median level 100 and 182IU/ml respectively); in three out of CVL-sera (level 94IU), and in only one HIEA-serum (level 58IU). IgA-RF was only detected in RA-sera (5/10, 50%), while CCP-Ab was found in three VL and in four RA sera (median level 36.5U and 161.5U respectively). A strong correlation was observed between RF-IgM and VL in endemic area (P<0.0001). We concluded that an increased IgM-RF production associated with sporadic and moderate CCP-Ab synthesis is an autoimmune characteristic of VL.

Genome-wide scan for visceral leishmaniasis susceptibility genes in Brazil.

A genome-wide scan was conducted for visceral leishmaniasis (VL) in Brazil. Initially, 405 markers were typed in 22 multicase pedigrees (28 nuclear families; 174 individuals; 66 affected). Non-parametric multipoint analysis detected nine chromosomal regions with provisional evidence (logarithm of the odds (LOD) scores 0.95-1.66; 0.003

Atypical American visceral leishmaniasis caused by disseminated Leishmania amazonensis infection presenting with hepatitis and adenopathy.

Leishmania amazonensis is widely recognised as a cause of cutaneous leishmaniasis in Latin America, but it can also disseminate to produce atypical visceral leishmaniasis with hepatitis and lymphadenopathy. The patient, an 8-year-old Brazilian boy, presented with a febrile illness and hepatosplenomegaly, elevated liver enzymes and generalised adenopathy. Serological tests using antigens of L. chagasi, the typical cause of visceral leishmaniasis in Latin America, were inconclusive. Leishmania amazonensis was eventually isolated in a culture of a lymph node. The patient recovered fully after treatment with meglumine antimoniate. As this case illustrates, L. amazonensis produces a spectrum of disease that includes atypical American visceral leishmaniasis with evidence of hepatocellular injury and generalised lymphadenopathy.

Recombinant leishmania antigens for serodiagnosis of visceral leishmaniasis.

Serological tests with crude or recombinant Leishmania antigens are important tools for the diagnosis of leishmania infection. However, these tests are not markers of active visceral leishmaniasis (VL), since antibodies to these markers are often observed in individuals with subclinical L. chagasi infection and they do not fall shortly after therapy. In this study, levels of immunoglobulin G (IgG) against three recombinant Leishmania antigens (rH2A, KMP11, and the "Q" protein) were evaluated in sera from individuals with subclinical L. chagasi infection and in patients with VL pre- and posttherapy. The sensitivity of the serological test for diagnosis of VL was 100% with all three antigens. The titers of IgG fell significantly after therapy. While most of the individuals with subclinical L. chagasi infection had antibodies to rH2A and the "Q" protein, only 1 out of 15 individuals had antibodies to KMP11. These data indicate that KMP11 may be used to discriminate L. chagasi infection from active VL and may serve as a marker of response to therapy.

Antileishmanial IgG and IgE antibodies recognize predominantly carbohydrate epitopes of glycosylated antigens in visceral leishmaniasis.

The specificity of human antileishmanial IgG and IgE antibodies to glycosylated antigens of Leishmania chagasi was evaluated. An ELISA was performed with soluble leishmanial antigen (SLA) and a panel of 95 sera including samples from patients with subclinical infection (SC) and visceral leishmaniasis (VL), subjects cured of visceral leishmaniasis (CVL), and from healthy individuals from endemic areas (HIEA). Antileishmanial IgG were verified for 18 (40%) of 45 SC subjects (mean absorbance of 0.49 +/- 0.17). All nine sera from VL patients had such antibody (0.99 +/- 0.21), while 11 (65%) of 17 CVL individuals were seropositive (0.46 +/- 0.05). Only three (12%) of 24 HIEA controls reacted in IgG-ELISA. Antileishmanial IgE was detected in 26 (58%) of 45 SC patients (0.35 +/- 0.14), and in all VL patients (0.65 +/- 0.29). These antibodies were also detected in 13(76%) of 17 CVL subjects (0.42 +/- 0.14) while all HIEA controls were seronegative. There was no correlation between antileishmanial IgG and IgE antibody absorbances. Mild periodate oxidation at acid pH of SLA carbohydrates drastically diminished its antigenicity in both IgG and IgE-ELISA, affecting mainly the antigens of 125, 102, 94, and 63 kDa as demonstrated by western immunoblotting.

Antileishmanial IgG and IgE antibodies recognize predominantly carbohydrate epitopes of glycosylated antigens in visceral leishmaniasis

The specificity of human antileishmanial IgG and IgE antibodies to glycosylated antigens of Leishmania chagasi was evaluated. An ELISA was performed with soluble leishmanial antigen (SLA) and a panel of 95 sera including samples from patients with subclinical infection (SC) and visceral leishmaniasis (VL), subjects cured of visceral leishmaniasis (CVL), and from healthy individuals from endemic areas (HIEA). Antileishmanial IgG were verified for 18 (40 percent) of 45 SC subjects (mean absorbance of 0.49 ± 0.17). All nine sera from VL patients had such antibody (0.99 ± 0.21), while 11 (65 percent) of 17 CVL individuals were seropositive (0.46 ± 0.05). Only three (12 percent) of 24 HIEA controls reacted in IgG-ELISA. Antileishmanial IgE was detected in 26 (58 percent) of 45 SC patients (0.35 ± 0.14), and in all VL patients (0.65 ± 0.29). These antibodies were also detected in 13(76 percent) of 17 CVL subjects (0.42 ± 0.14) while all HIEA controls were seronegative. There was no correlation between antileishmanial IgG and IgE antibody absorbances. Mild periodate oxidation at acid pH of SLA carbohydrates drastically diminished its antigenicity in both IgG and IgE-ELISA, affecting mainly the antigens of 125, 102, 94, and 63 kDa as demonstrated by western immunoblotting.

Comparative genomics of two Leptospira interrogans serovars reveals novel insights into physiology and pathogenesis.

Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in accidental hosts, including humans. Complete genome sequencing of Leptospira interrogans serovar Copenhageni and comparative analysis with the available Leptospira interrogans serovar Lai genome reveal that despite overall genetic similarity there are significant structural differences, including a large chromosomal inversion and extensive variation in the number and distribution of insertion sequence elements. Genome sequence analysis elucidates many of the novel aspects of leptospiral physiology relating to energy metabolism, oxygen tolerance, two-component signal transduction systems, and mechanisms of pathogenesis. A broad array of transcriptional regulation proteins and two new families of afimbrial adhesins which contribute to host tissue colonization in the early steps of infection were identified. Differences in genes involved in the biosynthesis of lipopolysaccharide O side chains between the Copenhageni and Lai serovars were identified, offering an important starting point for the elucidation of the organism's complex polysaccharide surface antigens. Differences in adhesins and in lipopolysaccharide might be associated with the adaptation of serovars Copenhageni and Lai to different animal hosts. Hundreds of genes encoding surface-exposed lipoproteins and transmembrane outer membrane proteins were identified as candidates for development of vaccines for the prevention of leptospirosis.

Anti-ganglioside antibodies and clinical outcome of patients with Guillain-Barré Syndrome in northeast Brazil.

OBJECTIVES: The goal of this study was to investigate the frequency of GM1 antibodies and to assess whether exposure to Campylobacter jejuni was associated with a distinct clinical variant of Guillain-Barré Syndrome (GBS) or disease outcome in Rio Grande do Norte, Brazil. MATERIAL AND METHODS: Forty-one patients with a presumed diagnosis of GBS were enrolled and prospectively studied between June 1994 and November 1999. RESULTS: Anti-GM1 was present in 51.2% (n = 21) of patients. The presence of anti-GM1 was significantly associated with acute axonal motor neuropathy when compared to acute inflammatory demyelinating polyneuropathy (P = 0.01). Patients with anti-GM1 antibodies presented distal muscle involvement and fewer sensory deficits. Age, time to nadir and ventilatory assistance were not associated with anti-GM1 antibodies. Eight out of 21 patients (32%) presented with anti-C. jejuni antibodies. Clinical features were similar for patients with GBS with positive and negative C. jejuni antibodies. Anti-GM1 antibodies were associated with C. jejuni infection (P = 0.0005). Presence of anti-GM1 and C. jejuni antibodies did not indicate a worse prognosis. CONCLUSION: Patients with GBS and anti-GM1 antibodies had more distal muscle weakness, fewer sensory deficits, more axonal degeneration and C. jejuni infection, but these findings were not associated with a worse prognosis.

Characteristics of the biological cycle of Lutzomyia evandroi Costa Lima & Antunes, 1936 (Diptera: Psychodidae) under experimental conditions.

Lutzomyia evandroi Costa Lima and Antunes, 1936 is found in Rio Grande do Norte, northeastern Brazil, in areas of visceral and mucocutaneous leishmaniasis and follows the same geographic distribution of L. longipalpis. The biological cycle, oviposition, morphological and behavioral characteristics of the species were studied under experimental conditions. The average number of eggs per wild caught female varied from 21 to 50 eggs along the year, with a peak occurring between January and March and another in August, with oviposition lasting for 4 to 12 days. The mean larval phase was 24 days. Ovipositing rates were influenced by rainfall and temperature indexes, with an increase of eggs per oviposition at the beginning and at the end of the rainy season, and a decrease at the peak of the rainy season.

Distribution of phlebotomine sand flies (Diptera: Psychodidae) in the state of Rio Grande do Norte, Brazil.

Visceral and cutaneous leishmaniasis are major endemic diseases in northeast Brazil. The objective of the current study was to determine the species and geographic distribution of potential sand fly vectors of Leishmania in the state of Rio Grande do Norte. Sand flies were captured using CDC light traps in 30 municipalities distributed throughout the 8 geographic zones of the state. Twelve Lutzomyia species were identified. Lutzomyia longipalpis Lutz & Neiva was the most prevalent and accounted for 85.59% of the sand fly captured. The remaining species were distributed as follows: L. evandroi Costa Lima & Antunes (10.83%), L. oswaldoi Mangabeira (0.99%), L. sallesi Galvão & Coutinho (0.58%), L. intermedia Lutz & Neiva (0.53%), L. lenti Mangabeira (0.53%), L. migonei França (0.49%), L. walkeri Newstead (0.24%), L. goiana Martins, Falcão & Silva (0.15%), L. samueli Deane (0.04%), and L. capixaba Dias, Falcão, Silva & Martins (0.03%), and L. peresi Mangabeira (0.01%). L. longipalpis, which is known to be a vector of Leishmania chagasi Cunha & Chagas (L. donovani chagasi), was captured in 93% of municipalities distributed across all geographical areas of the state and its distribution was independent of obvious climatic and topographic parameters. It was identified in all municipalities where human visceral leishmaniasis had been reported. In contrast, climate and topography appeared to be important for other Lutzomyia species. For example, L. intermedia and L. migonei, which are known to transmit Leishmania braziliensis Viana, were geographically restricted. They were captured in municipalities where cases of cutaneous and mucosal leishmaniasis had been reported. The widespread distribution of L. longipalpis, its adaptation to peridomicillary settings, and its ability to transmit L. (d.) chagasi suggest that a large number of persons may be at risk of acquiring visceral leishmaniasis in the state of Rio Grande do Norte, Brazil.

Heparan sulfates and heparins: similar compounds performing the same functions in vertebrates and invertebrates?

The distribution and structure of heparan sulfate and heparin are briefly reviewed. Heparan sulfate is a ubiquitous compound of animal cells whose structure has been maintained throughout evolution, showing an enormous variability regarding the relative amounts of its disaccharide units. Heparin, on the other hand, is present only in a few tissues and species of the animal kingdom and in the form of granules inside organelles in the cytoplasm of special cells. Thus, the distribution as well as the main structural features of the molecule, including its main disaccharide unit, have been maintained through evolution. These and other studies led to the proposal that heparan sulfate may be involved in the cell-cell recognition phenomena and control of cell growth, whereas heparin may be involved in defense mechanisms against bacteria and other foreign materials. All indications obtained thus far suggest that these molecules perform the same functions in vertebrates and invertebrates.

Heparan sulfates and heparins: similar compounds performing the same functions in vertebrates and invertebrates?

The distribution and structure of heparan sulfate and heparin are briefly reviewed. Heparan sulfate is a ubiquitous compound of animal cells whose structure has been maintained throughout evolution, showing an enormous variability regarding the relative amounts of its disaccharide units. Heparin, on the other hand, is present only in a few tissues and species of the animal kingdom and in the form of granules inside organelles in the cytoplasm of special cells. Thus, the distribution as well as the main structural features of the molecule, including its main disaccharide unit, have been maintained through evolution. These and other studies led to the proposal that heparan sulfate may be involved in the cell-cell recognition phenomena and control of cell growth, whereas heparin may be involved in defense mechanisms against bacteria and other foreign materials. All indications obtained thus far suggest that these molecules perform the same functions in vertebrates and invertebrates