Type I hyperprolinemia: genotype/phenotype correlations.

Type I hyperprolinemia (HPI) is an autosomal recessive disorder associated with cognitive and psychiatric troubles, caused by alterations of the Proline Dehydrogenase gene (PRODH) at 22q11. HPI results from PRODH deletion and/or missense mutations reducing proline oxidase (POX) activity. The goals of this study were first to measure in controls the frequency of PRODH variations described in HPI patients, second to assess the functional effect of PRODH mutations on POX activity, and finally to establish genotype/enzymatic activity correlations in a new series of HPI patients. Eight of 14 variants occurred at polymorphic frequency in 114 controls. POX activity was determined for six novel mutations and two haplotypes. The c.1331G>A, p.G444D allele has a drastic effect, whereas the c.23C>T, p.P8L allele and the c.[56C>A; 172G>A], p.[Q19P; A58T] haplotype result in a moderate decrease in activity. Among the 19 HPI patients, 10 had a predicted residual activity <50%. Eight out of nine subjects with a predicted residual activity > or = 50% bore at least one c.824C>A, p.T275N allele, which has no detrimental effect on activity but whose frequency in controls is only 3%. Our results suggest that PRODH mutations lead to a decreased POX activity or affect other biological parameters causing hyperprolinemia.

Characterization of the hemagglutinin receptor specificity and neuraminidase substrate specificity of clinical isolates of human influenza A viruses

Six clinical isolates of influenza A viruses were examined for hemagglutinin receptor specificity and neuraminidase substrate specificity. All of the viral isolates minimally passaged in mammalian cells demonstrated preferential agglutination of human erythrocytes enzymatically modified to contain NeuAc alpha 2,6Gal sequences, with no agglutination of cells bearing NeuAc alpha 2,3Gal sequences. This finding is consistent with the hemagglutination receptor specificity previously demonstrated for laboratory strains of influenza A viruses. The neuraminidase substrate specificities of the clinical isolates examined were also identical to that described for the N2 neuraminidase of recent laboratory strains of human influenza viruses. The H3N2 viruses all displayed the ability to release sialic acid from both alpha 2, 3 and alpha 2, 6 linkages. In addition, two clinical isolates of H1N1 viruses also demonstrated this dual neuraminidase substrate specificity, a characteristic which has not been previously described for the N1 neuraminidase. These results demonstrate that complementary hemagglutinin and neuraminidase specificities are found in recent isolates of both H1N1 and H3N2 influenza viruses.

Mutation in the gene for connexin 30.3 in a family with erythrokeratodermia variabilis.

Erythrokeratodermia variabilis (EKV) is an autosomal dominant keratinization disorder characterized by migratory erythematous lesions and fixed keratotic plaques. All families with EKV show mapping to chromosome 1p34-p35, and mutations in the gene for connexin 31 (Cx31) have been reported in some but not all families. We studied eight affected and three healthy subjects in an Israeli family, of Kurdish origin, with EKV. After having mapped the disorder to chromosome 1p34-p35, we found no mutations in the genes for Cx31, Cx31.1, and Cx37. Further investigation revealed a heterozygous T-->C transition leading to the missense mutation (F137L) in the human gene for Cx30.3 that colocalizes on chromosome 1p34-p35. This nucleotide change cosegregated with the disease and was not found in 200 alleles from normal individuals. This mutation concerns a highly conserved phenylalanine, in the third transmembrane region of the Cx30.3 molecule, known to be implicated in the wall formation of the gap-junction pore. Our results show that mutations in the gene for Cx30.3 can be causally involved in EKV and point to genetic heterogeneity of this disorder. Furthermore, we suggest that our family presents a new type of EKV because of the hitherto unreported association with erythema gyratum repens.

Wyeomyia luteoventralis Theobald, the type species of the subgenus Dendromyia Theobald (Diptera: Culicidae)

Wyeomyia (Dendromyia) luteoventralis is redescribed from females, males, larvae and pupae collected at the type locality, in Brazil, and compared to the closely related species. At least six species - Wy. luteoventralis, Wy. ypsipola, Wy. testei, Wy. trifurcata, Wy. complosa and Wy. jocosa - appparently, belong to a monophyletic group, the subgenus Dendromyia. All other species previously included in Dendromyia are hereby excluded from this subgenus and retained in genus Wyeomyia without subgeneric placement.

Dried blood spots collected on filter paper: an international resource for the diagnosis and genetic characterization of human immunodeficiency virus Type-1

The collection of dried blood spots (DBS) on filter paper provides a powerful approach for the development of large-scale, population-based screening programs. DBS methods are particularly valuable in developing countries and isolated rural regions where resources are limited. Large numbers of field specimens can be economically collected and shipped to centralized reference laboratories for genetic and (or) serological analysis. Alternatively, the dried blood can be stored and used as an archival resource to rapidly establish the frequency and distribution of newly recognized mutations, confirm patient identity or track the origins and emergence of newly identified pathogens. In this report, we describe how PCR-based technologies are beginning to interface with international screening programmes for the diagnosis and genetic characterization of human immunodeficiency virus type 1 (HIV-1). In particular, we review recent progress using DBS specimens to resolve the HIV-1 infection status of neonates, monitor the genetic evolution of HIV-1 during early infancy and establish a sentinel surveillance system for the systematic monitoring of HIV-1 genetic variation in Asia.

IRF6 Screening of Syndromic and a priori Non-Syndromic Cleft Lip and Palate Patients: Identification of a New Type of Minor VWS Sign.

Van der Woude syndrome (VWS), caused by dominant IRF6 mutation, is the most common cleft syndrome. In 15% of the patients, lip pits are absent and the phenotype mimics isolated clefts. Therefore, we hypothesized that some of the families classified as having non-syndromic inherited cleft lip and palate could have an IRF6 mutation. We screened in total 170 patients with cleft lip with or without cleft palate (CL/P): 75 were syndromic and 95 were a priori part of multiplex non-syndromic families. A mutation was identified in 62.7 and 3.3% of the patients, respectively. In one of the 95 a priori non-syndromic families with an autosomal dominant inheritance (family B), new insights into the family history revealed the presence, at birth, of lower lip pits in two members and the diagnosis was revised as VWS. A novel lower lip sign was observed in one individual in this family. Interestingly, a similar lower lip sign was also observed in one individual from a 2nd family (family A). This consists of 2 nodules below the lower lip on the external side. In a 3rd multiplex family (family C), a de novo mutation was identified in an a priori non-syndromic CL/P patient. Re-examination after mutation screening revealed the presence of a tiny pit-looking lesion on the inner side of the lower lip leading to a revised diagnosis of VWS. On the basis of this data, we conclude that IRF6 should be screened when any doubt rises about the normality of the lower lip and also if a non-syndromic cleft lip patient (with or without cleft palate) has a family history suggestive of autosomal dominant inheritance.

The type of K-ras mutation determines prognosis in colorectal cancer.

BACKGROUND: Mutations involving the oncogene K-ras in colorectal cancer may be related to tumor aggressiveness. However, the value of K-ras gene determination as a prognostic marker has not been clearly established. PATIENTS AND METHODS: The results from 98 patients recruited in a prospective study analyzing the effect of a K-ras mutation as a prognostic factor in colorectal cancer are reported. RESULTS: Disease-free (P = 0.02) and overall survival (P = 0.03) were significantly reduced for patients harboring a K-ras mutation. Two specific mutations demonstrated a significantly increased risk of disease recurrence, namely, 12-TGT (P = 0.04) and 13-GAC substitutions (P = 0.002). Patients with either of these substitutions had a 2-year disease-free survival rate of 37% compared with that of 67% for the group of patients harboring any other mutation type or a wild-type status (P = 0.01). CONCLUSIONS: The results herein presented suggest that K-ras acts as a prognostic factor in colorectal cancer and that this effect is probably related to a limited number of defined mutations.

The Type Specimens of Apoidea (Hymenoptera) Deposited in the Entomological Collection of Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil

A list of 41 Apoidea (Hymenoptera) type specimens deposited in the Entomological Collection of the Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil is presented. The types previously belonged to the Zikán and Schrottky private collections. A total of 11 holotypes and 30 paratypes are listed with their respective data and literature

Prevention du diabète de type 2: état des connaissances [Prevention of type 2 diabetes: where do we stand?]

It is anticipated that one out of 3 children born in the year 2000 in the United States may develop diabetes. In Switzerland, a population based study in the city of Lausanne (CoLaus) has shown that about 30% of the participants have abnormal glucose homeostasis, and that the prevalence of obesity in the younger age groups has doubled since 1992. In this review, we describe clinical and biological factors associated with an increased risk to develop diabetes and summarize the most important intervention studies that have shown a beneficial effect in the prevention of diabetes. While life style modifications should be recommended for everybody, the place of pharmacological interventions (oral hypoglycemic agents, blood pressure and cholesterol lowering agents) is more controversial.

HIV type 1 drug resistance among naive patients from Venezuela.

In this study, we characterize proviral DNA of 20 HIV-1 asymptomatic antiretroviral-naive patients from Venezuela in env, gag, and pol genes regions. Results from both env/gag HMA subtyping and phylogenetic analysis of pol partial sequences led to the description of clade B in all cases. Nevertheless, the high prevalence of polymorphisms was particularly evident among the protease sequences. A 10% prevalence of major resistance mutations to RTIs was found. Our data also suggested that the protease polymorphisms I62T and V77T could be considered as molecular markers of the subtype B local epidemic. In addition, we show how proviral DNA can be used as a reliable tool to follow trends of resistance mutation transmission.

Estimating the risk of developing type 2 diabetes: a comparison of several risk scores: the Cohorte Lausannoise study.

To compare in the Swiss population the results of several scores estimating the risk of developing type 2 diabetes. This was a single-center, cross-sectional study conducted between 2003 and 2006 in Lausanne, Switzerland. Overall, 3,251 women and 2,937 men, aged 35-75 years, were assessed, of which 5,760 (93%) were free from diabetes and included in the current study. The risk of developing type 2 diabetes was assessed using seven different risk scores, including clinical data with or without biological data. Participants were considered to be eligible for primary prevention according to the thresholds provided for each score. The results were then extrapolated to the Swiss population of the same sex and age. The risk of developing type 2 diabetes increased with age in all scores. The prevalence of participants at high risk ranged between 1.6 and 24.9% in men and between 1.1 and 15.7% in women. Extrapolated to the Swiss population of similar age, the overall number of participants at risk, and thus susceptible to intervention, ranged between 46,708 and 636,841. In addition, scores that included the same clinical variables led to a significantly different prevalence of participants at risk (4.2% [95% CI 3.4-5.0] vs. 12.8% [11.5-14.1] in men and 2.9% [2.4-3.6] vs. 6.0% [5.2-6.9] in women). CONCLUSIONS; The prevalence of participants at risk for developing type 2 diabetes varies considerably according to the scoring system used. To adequately prevent type 2 diabetes, risk-scoring systems must be validated for each population considered.

Early expression of the type III secretion system of Parachlamydia acanthamoebae during a replicative cycle within its natural host cell Acanthamoeba castellanii.

The type three secretion system (T3SS) operons of Chlamydiales bacteria are distributed in different clusters along their chromosomes and are conserved at both the level of sequence and genetic organization. A complete characterization of the temporal expression of multiple T3SS components at the transcriptional and protein levels has been performed in Parachlamydia acanthamoebae, replicating in its natural host cell Acanthamoeba castellanii. The T3SS components were classified in four different temporal clusters depending on their pattern of expression during the early, mid- and late phases of the infectious cycle. The putative T3SS transcription units predicted in Parachlamydia are similar to those described in Chlamydia trachomatis, suggesting that T3SS units of transcriptional expression are highly conserved among Chlamydiales bacteria. The maximal expression and activation of the T3SS of Parachlamydia occurred during the early to mid-phase of the infectious cycle corresponding to a critical phase during which the intracellular bacterium has (1) to evade and/or block the lytic pathway of the amoeba, (2) to differentiate from elementary bodies (EBs) to reticulate bodies (RBs), and (3) to modulate the maturation of its vacuole to create a replicative niche able to sustain efficient bacterial growth.

Risk Factors for Human T Cell Lymphotropic Virus Type I among Injecting Drug Users in Northeast Brazil: Possibly Greater Efficiency of Male to Female Transmission

It was observed in the city of Salvador, State of Bahia, the highest seroprevalence of human T cell lymphotropic virus type 1 (HTLV-I) infection in Brazil as demonstrated by national wide blood bank surveys. In this paper, we report results of an investigation of drug use and sexual behavior associated with HTLV-I infection among male and female injecting drug users (IDUs) in Salvador. A cross sectional study was conducted in the Historical District of Salvador from 1994-1996 (Projeto Brasil-Salvador) and 216 asymptomatic IDUs were selected using the snowball contact technique. Blood samples were collected for serological assays. Sera were screened for human immunodeficiency virus (HIV-1/2) and HTLV-I/II antibodies by ELISA and confirmed by Western blot. The overall prevalence of HTLV-I/II was 35.2% (76/216). The seroprevalence of HTLV-I, HTLV-II and HIV-1 was for males 22%, 11.3% and 44.1% and for females 46.2%, 10.3% and 74.4% respectively. HTLV-I was identified in 72.4% of HTLV positive IDUs. Variables which were significantly associated with HTLV-I infection among males included needle sharing practices, duration of injecting drug use, HIV-1 seropositivity and syphilis. Among women, duration of injecting drug use and syphilis were strongly associated with HTLV-I infection. Multivariate analysis did not change the direction of these associations. Sexual intercourse might play a more important role in HTLV-I infection among women than in men.

Increased Pro-inflammatory Cytokines (TNF-a and IL-6) and Anti-inflammatory Compounds (sTNFRp55 and sTNFRp75) in Brazilian Patients during Exanthematic Dengue Fever

Pro-inflammatory cytokines, tumor necrosis factor (TNF-a), interleukin-6 (IL-6) and interleukin-1b (IL-1b) as well as anti-inflammatory compounds, soluble TNF-Receptor p55 (sTNFRp55), sTNFRp75 and IL-1 receptor antagonist (sIL-1Ra), were investigated in 34 Brazilian cases of dengue fever (DF) originated from a study of exanthematic virosis. The presence of pro-inflammatory cytokines was detected in sera from these patients by ELISA. TNF-a and IL-6 levels were significantly higher than control subjects in 32% and 52% patients, respectively. To our knowledge this was the first time a receptor antagonist and soluble receptors for cytokines were detected in sera obtained during exanthematic DF without hemorrhagic manifestations. Both sTNFRp55 and sTNFRp75 were consistently elevated in 42% and 84% patients, respectively. Most patients had IL-1b levels not different from those of normal subjects, except for one case. Only 16% patients had altered levels of IL-1Ra. Previous studies in dengue hemorrhagic fever patients demonstrated production of these soluble factors; here we observed that they are found in absence of hemorrhagic manifestations. The possible role of these anti-inflammatory compounds in immune cell activation and in regulating cytokine-mediated pathogenesis during dengue infection is discussed.