Accurate, Fast and Cost-Effective Diagnostic Test for\ud Monosomy 1p36 Using Real-Time Quantitative PCR

Monosomy 1p36 is considered the most common subtelomeric deletion syndrome in humans and it accounts for 0.5–0.7% of all\ud the cases of idiopathic intellectual disability. The molecular diagnosis is often made by microarray-based comparative genomic\ud hybridization (aCGH), which has the drawback of being a high-cost technique. However, patients with classic monosomy 1p36\ud share some typical clinical characteristics that, together with its common prevalence, justify the development of a less expensive,\ud targeted diagnostic method. In this study, we developed a simple, rapid, and inexpensive real-time quantitative PCR (qPCR) assay\ud for targeted diagnosis of monosomy 1p36, easily accessible for low-budget laboratories in developing countries. For this, we have\ud chosen two target genes which are deleted in the majority of patients with monosomy 1p36: PRKCZ and SKI. In total, 39 patients\ud previously diagnosed with monosomy 1p36 by aCGH, fluorescentin situhybridization (FISH), and/or multiplex ligation-dependent\ud probe amplification (MLPA) all tested positive on our qPCR assay. By simultaneously using these two genes we have been able to\ud detect 1p36 deletions with 100% sensitivity and 100% specificity. We conclude that qPCR of PRKCZ and SKI is a fast and accurate\ud diagnostic test for monosomy 1p36, costing less than 10 US dollars in reagent costs

Asymptotic Behavior of the Solution to a Nonisentropic Hydrodynamic Model of Semiconductors

AbstractWe study the asymptotic behavior of the solution for a hydrodynamic model of semiconductors where the energy equation is included. We study the case where the flow is subsonic and the doping profile is close to a negative constant, depending on the spacial variablex. We shall show that a given steady state solution is asymptotically stable or unstable depending on whether or not the density of the initial data satisfiesP=0, wherePis defined in (3.5)

Coinfection with Different Trypanosoma cruzi Strains Interferes with the Host Immune Response to Infection

A century after the discovery of Trypanosoma cruzi in a child living in Lassance, Minas Gerais, Brazil in 1909, many uncertainties remain with respect to factors determining the pathogenesis of Chagas disease (CD). Herein, we simultaneously investigate the contribution of both host and parasite factors during acute phase of infection in BALB/c mice infected with the JG and/or CL Brener T. cruzi strains. JG single infected mice presented reduced parasitemia and heart parasitism, no mortality, levels of pro-inflammatory mediators (TNF-α, CCL2, IL-6 and IFN-γ) similar to those found among naïve animals and no clinical manifestations of disease. On the other hand, CL Brener single infected mice presented higher parasitemia and heart parasitism, as well as an increased systemic release of pro-inflammatory mediators and higher mortality probably due to a toxic shock-like systemic inflammatory response. Interestingly, coinfection with JG and CL Brener strains resulted in intermediate parasitemia, heart parasitism and mortality. This was accompanied by an increase in the systemic release of IL-10 with a parallel increase in the number of MAC-3+ and CD4+ T spleen cells expressing IL-10. Therefore, the endogenous production of IL-10 elicited by coinfection seems to be crucial to counterregulate the potentially lethal effects triggered by systemic release of pro-inflammatory mediators induced by CL Brener single infection. In conclusion, our results suggest that the composition of the infecting parasite population plays a role in the host response to T. cruzi in determining the severity of the disease in experimentally infected BALB/c mice. The combination of JG and CL Brener was able to trigger both protective inflammatory immunity and regulatory immune mechanisms that attenuate damage caused by inflammation and disease severity in BALB/c mice

The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability

Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications

Screening fetal losses for monosomy X with a simple PCR-based procedure

To screen for monosomy X in spontaneous fetal losses we explored a simple molecular strategy based on loss of heterozygosity at highly polymorphic X-linked loci. We developed a multiplex fluorescent procedure that allows the simultaneous amplification of five dinucleotide repeat polymorphisms in a large low-recombination region in the long arm of the X chromosome. Analysis was performed by computer-assisted laser densitometry. We did not find any instances of homozygosity at all five loci in 30 normal females tested, nor among 37 women whose typing data were retrieved from the Fondation Jean Dausset - CEPH genotype database. In addition, all cases of monosomy X previously diagnosed by conventional cytogenetics presented the anticipated loss of heterozygosity at all loci. We studied 19 spontaneously aborted female fetuses and we found four samples homozygous for the five loci (21%), in good agreement with the expected rate of monosomy X in first trimester spontaneous abortions. We conclude that the loci have high diversity and high efficiency in PCR-amplification and that our multiplex procedure constitutes a simple and useful molecular screening test for monosomy X in abortions and stillbirths

Detecção de papilomavirus humano em displasias ou neoplasias cervicais e em condilomas acuminados por hibridização in situ com sondas de DNA biotiniladas

Specimens from cervical dysplasias or carcinomas and genital condylomata acuminata were retrospectively analysed by in situ hybridization (ISH) with bioti-nylated DNA probes for human papillomavirus (HPV) types 6, 11, 16 and 18. In the control group no case was positive for HPV DNA. In mild/moderate dysplasias, 4 cases (14%) were positive for HPV 6 or 11 and 2 cases (7%), for HPV 16. In the severe dysplasia/in situ carcinoma group, 9 cases (31%) showed presence of DNA of HPV types 16 or 18. Six invasive carcinomas (20%) were positive for HPV type 16 or 18. Among condylomata acuminata, 22 cases (73%) were positive for HPV types 6 or 11. In all ISH-positive cases only one viral type was detected. No correlation between HPV DNA positivity and histological findings of HPV infection was observed. Although less sensitive than some other molecular biology techniques, in situ hybridization with biotinylated DNA probes proved to be simple and useful for detecting and typing HPV in samples routinely received for histopathological analysis.Amostras de displasias ou carcinomas do colo uterino e de condilomas acuminados da região genital foram analisados retrospectivamente por hibridização in situ (HIS) com sondas de DNA biotiniladas de papilomavirus humano (HPV) tipos 6, 11, 16 e 18. Nenhum caso do grupo controle foi positivo para DNA de HPV. Em displasias leve/moderada, 4 casos (14%) foram positivos para HPV 6 ou 11 e 2 casos (7%), para HPV 16. No grupo de displasia acentuada/carcinoma in situ, 9 casos (31%) tinham DNA de HPV tipos 16 ou 18. Seis carcinomas invasores (20%) foram positivos para HPV tipos 16 ou 18. Entre os condilomas acuminados, 22 casos (73%) foram positivos para HPV tipos 6 ou 11. Em todos os casos positivos pela HIS somente um tipo viral foi encontrado. Não foi observada correlação entre a positividade para DNA de HPV e achados histológicos de infecção por HPV. Apesar de menos sensível que algumas outras técnicas de biologia molecular, a hibridização in situ com sondas de DNA biotiniladas mostrou-se simples e adequada para detecção e tipagem de HPV em amostras enviadas rotineiramente para estudo histopatológico

Human papillomavirus detection in cervical dysplasias or neoplasias and in condylomata acuminaata by in situ hybridization with biotinylated DNA probes Detecção de papilomavirus humano em displasias ou neoplasias cervicais e em condilomas acuminados por hibridização in situ com sondas de DNA biotiniladas

Specimens from cervical dysplasias or carcinomas and genital condylomata acuminata were retrospectively analysed by in situ hybridization (ISH) with bioti-nylated DNA probes for human papillomavirus (HPV) types 6, 11, 16 and 18. In the control group no case was positive for HPV DNA. In mild/moderate dysplasias, 4 cases (14%) were positive for HPV 6 or 11 and 2 cases (7%), for HPV 16. In the severe dysplasia/in situ carcinoma group, 9 cases (31%) showed presence of DNA of HPV types 16 or 18. Six invasive carcinomas (20%) were positive for HPV type 16 or 18. Among condylomata acuminata, 22 cases (73%) were positive for HPV types 6 or 11. In all ISH-positive cases only one viral type was detected. No correlation between HPV DNA positivity and histological findings of HPV infection was observed. Although less sensitive than some other molecular biology techniques, in situ hybridization with biotinylated DNA probes proved to be simple and useful for detecting and typing HPV in samples routinely received for histopathological analysis.<br>Amostras de displasias ou carcinomas do colo uterino e de condilomas acuminados da região genital foram analisados retrospectivamente por hibridização in situ (HIS) com sondas de DNA biotiniladas de papilomavirus humano (HPV) tipos 6, 11, 16 e 18. Nenhum caso do grupo controle foi positivo para DNA de HPV. Em displasias leve/moderada, 4 casos (14%) foram positivos para HPV 6 ou 11 e 2 casos (7%), para HPV 16. No grupo de displasia acentuada/carcinoma in situ, 9 casos (31%) tinham DNA de HPV tipos 16 ou 18. Seis carcinomas invasores (20%) foram positivos para HPV tipos 16 ou 18. Entre os condilomas acuminados, 22 casos (73%) foram positivos para HPV tipos 6 ou 11. Em todos os casos positivos pela HIS somente um tipo viral foi encontrado. Não foi observada correlação entre a positividade para DNA de HPV e achados histológicos de infecção por HPV. Apesar de menos sensível que algumas outras técnicas de biologia molecular, a hibridização in situ com sondas de DNA biotiniladas mostrou-se simples e adequada para detecção e tipagem de HPV em amostras enviadas rotineiramente para estudo histopatológico

Sequencing and Identification of Expressed Schistosoma mansoni Genes by Random Selection of cDNA Clones from a Directional Library

We have initiated a gene discovery program in Schistosoma mansoni   based on the technique of Expressed Sequence Tags (ESTs), i.e. partial sequences of cDNAs obtained from single passes in automatic DNA sequencers. ESTs can be used to identify genes on the basis of their homology with sequences from other species deposited in DNA or protein databases. Transcripts with sequences without matches in the databases may represent novel parasite-specific genes. This approach has shown to be very efficient and in less than two years a broad range of novel genes has already been ascertained, more than doubling the number of known S. mansoni genes

RESEARCH NOTE - Characterization of an Abundant Schistosoma mansoni Transcript with No Homologs in the Databases

The expressed sequence tag (EST) approach that we have used in the Schistosoma mansoni Genome Project is a powerful technique for the discovery of new genes of the parasite. In a recent comparative study of gene expression in distinct developmental stages of the parasite life cycle using the EST strategy, we identified 466 different genes. From this total, 427 were novel and 333 of them could not be identified based on homologies with database sequences. The high frequency of some of these "unknown" genes in different cDNA libraries suggests that they might have important roles in the biology of S. mansoni and thus may constitute possible targets for drug design or vaccine production. One of these genes, highly abundant in one of four adult worm libraries that we are studying in our laboratory, was selected for further characterization