Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
3.
Am J Obstet Gynecol ; 223(2): 167-176, 2020 08.
Article in English | MEDLINE | ID: mdl-32008730

ABSTRACT

Progesterone is essential for the maintenance of pregnancy. Several small trials have suggested that progesterone supplementation may reduce the risk of miscarriage in women with recurrent or threatened miscarriage. Cochrane Reviews summarized the evidence and found that the trials were small with substantial methodologic weaknesses. Since then, the effects of first-trimester use of vaginal micronized progesterone have been evaluated in 2 large, high-quality, multicenter placebo-controlled trials, one targeting women with unexplained recurrent miscarriages (the PROMISE [PROgesterone in recurrent MIScarriagE] trial) and the other targeting women with early pregnancy bleeding (the PRISM [PRogesterone In Spontaneous Miscarriage] trial). The PROMISE trial studied 836 women from 45 hospitals in the United Kingdom and the Netherlands and found a 3% greater live birth rate with progesterone but with substantial statistical uncertainty. The PRISM trial studied 4153 women from 48 hospitals in the United Kingdom and found a 3% greater live birth rate with progesterone, but with a P value of .08. A key finding, first observed in the PROMISE trial, and then replicated in the PRISM trial, was that treatment with vaginal micronized progesterone 400 mg twice daily was associated with increasing live birth rates according to the number of previous miscarriages. Prespecified PRISM trial subgroup analysis in women with the dual risk factors of previous miscarriage(s) and current pregnancy bleeding fulfilled all 11 conditions for credible subgroup analysis. For the subgroup of women with a history of 1 or more miscarriage(s) and current pregnancy bleeding, the live birth rate was 75% (689/914) with progesterone vs 70% (619/886) with placebo (rate difference 5%; risk ratio, 1.09, 95% confidence interval, 1.03-1.15; P=.003). The benefit was greater for the subgroup of women with 3 or more previous miscarriages and current pregnancy bleeding; live birth rate was 72% (98/137) with progesterone vs 57% (85/148) with placebo (rate difference 15%; risk ratio, 1.28, 95% confidence interval, 1.08-1.51; P=.004). No short-term safety concerns were identified from the PROMISE and PRISM trials. Therefore, women with a history of miscarriage who present with bleeding in early pregnancy may benefit from the use of vaginal micronized progesterone 400 mg twice daily. Women and their care providers should use the findings for shared decision-making.


Subject(s)
Abortion, Habitual/prevention & control , Abortion, Threatened/drug therapy , Progesterone/therapeutic use , Progestins/therapeutic use , Administration, Intravaginal , Female , Humans , Pregnancy , Pregnancy Trimester, First , Progesterone/administration & dosage , Progestins/administration & dosage , Randomized Controlled Trials as Topic , Treatment Outcome
4.
Sci Justice ; 55(2): 124-30, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25753998

ABSTRACT

Extracting viable DNA from many forensic sample types can be very challenging, as environmental conditions may be far from optimal with regard to DNA preservation. Consequently, skeletal tissue can often be an invaluable source of DNA. The bone matrix provides a hardened material that encapsulates DNA, acting as a barrier to environmental insults that would otherwise be detrimental to its integrity. However, like all forensic samples, DNA in bone can still become degraded in extreme conditions, such as intense heat. Extracting DNA from bone can be laborious and time-consuming. Thus, a lot of time and money can be wasted processing samples that do not ultimately yield viable DNA. We describe the use of colorimetry as a novel diagnostic tool that can assist DNA analysis from heat-treated bone. This study focuses on characterizing changes in the material and physical properties of heated bone, and their correlation with digitally measured color variation. The results demonstrate that the color of bone, which serves as an indicator of the chemical processes that have occurred, can be correlated with the success or failure of subsequent DNA amplification.


Subject(s)
Bone and Bones/chemistry , Burns , Colorimetry , DNA/analysis , Animals , Cattle , DNA Fingerprinting , Fires , Forensic Pathology , Polymerase Chain Reaction
5.
J Virol ; 88(13): 7120-9, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24719413

ABSTRACT

UNLABELLED: We investigated the migration patterns of hepatitis C virus (HCV) in China. Partial E1 and/or NS5B sequences from 411 volunteer blood donors sampled in 17 provinces and municipalities located in five large regions, the north-northeast, northwest, southwest, central south, and southeast, were characterized. The sequences were classified into eight subtypes (1a, n = 3; 1b, n = 183; 2a, n = 83; 3a, n = 30; 3b, n = 44; 6a, n = 55; 6n, n = 10; 6v, n = 1) and a new subtype candidate. Bayesian evolutionary analysis by sampling trees of the E1 sequences of the five major subtypes revealed distinct migration patterns. Subtype 1b showed four groups: one is prevalent nationwide with possible origins in the north-northeast; two are locally epidemic in the central south and northwest, respectively, and have spread sporadically to other regions; and the fourth one is likely linked to the long-distance dispersion among intravenous drug users from the northwest. Subtype 2a showed two groups: the larger one was mainly restricted to the northwest and seemed to show a trend toward migration via the Silk Road; the smaller one was geographically mixed and may represent descendants of those that spread widely during the contaminated plasma campaign in the 1990s. Subtype 3a exhibited three well-separated geographic groups that may be epidemically unrelated: one showed origins in the northwest, one showed origins in the southwest, and the other showed origins in the central south. In contrast, subtype 3b had a mixture of geographic origins, suggesting migrations from the southwest to the northwest and sporadically to other regions. Structurally resembling the tree for subtype 3a, the tree for subtype 6a showed four groups that may indicate migrations from the central south to southeast, southwest, and northwest. Strikingly, no subtype 6a strain was identified in the north-northeast. IMPORTANCE: With a population of greater than 1.3 billion and a territory of >9.6 million square kilometers, China has a total of 34 provinces and municipalities. In such a vast country, the epidemic history and migration trends of HCV are thought to be unique and complex but variable among regions and are unlikely to be represented by those observed in only one or at best a few provinces and municipalities. However, due to the difficulties in recruiting patients, all previous studies for this purpose have been based only on data from limited regions, and therefore, geographical biases were unavoidable. In this study, such biases were greatly reduced because we utilized samples collected from volunteer blood donors in 17 provinces and municipalities. To our knowledge, this is the first study in which the HCV isolates represented such a large portion of the country, and thus, the results should shed light on the current understanding of HCV molecular epidemiology.


Subject(s)
Blood Donors , Gene Flow/genetics , Hepacivirus/genetics , Hepatitis C/epidemiology , China/epidemiology , Genotype , Hepacivirus/classification , Hepacivirus/isolation & purification , Hepatitis C/virology , Humans , Molecular Epidemiology , Phylogeny , Phylogeography , Prevalence , RNA, Viral/genetics , Sequence Analysis, DNA , Viral Envelope Proteins/genetics , Viral Nonstructural Proteins/genetics , Volunteers
6.
J Forensic Leg Med ; 20(6): 757-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23910876

ABSTRACT

This case study reports on DNA analysis from different skeletal elements of an individual recovered 2 years after going missing in the English Channel. Selected bones were also re-submerged for an additional 2 years and re-analysed. By comparing results from both time points, this study concludes that high-load-bearing bones, particularly the bones of the feet, appear to be a preferable source of DNA for identification of skeletal tissue recovered from similar conditions.


Subject(s)
Bone and Bones/chemistry , DNA Fingerprinting/methods , DNA/isolation & purification , Immersion , Atlantic Ocean , Humans , Male , Microsatellite Repeats , Polymerase Chain Reaction
7.
J Gen Virol ; 94(Pt 8): 1780-1790, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23677792

ABSTRACT

In this study, we characterized the full-length genome sequences of seven hepatitis C virus (HCV) isolates belonging to genotype 1. These represent the first complete genomes for HCV subtypes 1e, 1h, 1l, plus one novel variant that qualifies for a new but unassigned subtype. The genomes were characterized using 19-22 overlapping fragments. Each was 9400-9439 nt long and contained a single ORF encoding 3019-3020 amino acids. All viruses were isolated in the sera of seven patients residing in, or originating from, Cameroon. Predicted amino acid sequences were inspected and unique patterns of variation were noted. Phylogenetic analysis using full-length sequences provided evidence for nine genotype 1 subtypes, four of which are described for the first time here. Subsequent phylogenetic analysis of 141 partial NS5B sequences further differentiated 13 subtypes (1a-1m) and six additional unclassified lineages within genotype 1. As a result of this study, there are now seven HCV genotype 1 subtypes (1a-1c, 1e, 1g, 1h, 1l) and two unclassified genotype 1 lineages with full-length genomes characterized. Further analysis of 228 genotype 1 sequences from the HCV database with known countries is consistent with an African origin for genotype 1, and with the hypothesis of subsequent dissemination of some subtypes to Asia, Europe and the Americas.


Subject(s)
Genome, Viral , Hepacivirus/classification , Hepacivirus/genetics , Phylogeography , RNA, Viral/genetics , Aged , Aged, 80 and over , Cameroon , Cluster Analysis , Evolution, Molecular , Female , Genotype , Hepacivirus/isolation & purification , Humans , Male , Molecular Sequence Data , Sequence Analysis, DNA
8.
J Infect Dis ; 208(1): 17-31, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23136221

ABSTRACT

BACKGROUND: Infection with hepatitis C virus (HCV) is a burgeoning worldwide public health problem, with 170 million infected individuals and an estimated 20 million deaths in the coming decades. While 6 main genotypes generally distinguish the global geographic diversity of HCV, a multitude of closely related subtypes within these genotypes are poorly defined and may influence clinical outcome and treatment options. Unfortunately, the paucity of genetic data from many of these subtypes makes time-consuming primer walking the limiting step for sequencing understudied subtypes. METHODS: Here we combined long-range polymerase chain reaction amplification with pyrosequencing for a rapid approach to generate the complete viral coding region of 31 samples representing poorly defined HCV subtypes. RESULTS: Phylogenetic classification based on full genome sequences validated previously identified HCV subtypes, identified a recombinant sequence, and identified a new distinct subtype of genotype 4. Unlike conventional sequencing methods, use of deep sequencing also facilitated characterization of minor drug resistance variants within these uncommon or, in some cases, previously uncharacterized HCV subtypes. CONCLUSIONS: These data aid in the classification of uncommon HCV subtypes while also providing a high-resolution view of viral diversity within infected patients, which may be relevant to the development of therapeutic regimens to minimize drug resistance.


Subject(s)
Hepacivirus/genetics , Antiviral Agents/therapeutic use , Base Sequence , Drug Resistance, Viral/genetics , Genetic Variation/genetics , Genome, Viral/genetics , Genotype , Hepacivirus/classification , Hepacivirus/drug effects , Hepatitis C/drug therapy , Hepatitis C/virology , Humans , Molecular Sequence Data , Phylogeny
9.
Forensic Sci Int Genet ; 6(3): 375-80, 2012 May.
Article in English | MEDLINE | ID: mdl-21963795

ABSTRACT

Deoxyribonucleic acid (DNA) extracted from skeletal tissue can be invaluable in genetic profiling applications, as it is often the only source available. Like all forensic samples, skeletal tissue may have been exposed to a variety of environmental insults, including heat. This study has focussed upon characterising changes in the material properties of bone that has been compromised by controlled heat treatments. These changes were then examined in relation to the subsequent success or failure of nuclear DNA (nDNA) amplification, using a range of differently sized amplicons, relevant to alternate profiling strategies. The results presented demonstrate that the ability to amplify nDNA correlates well with particular changes in mineral and organic content of bone. As such, we propose the application of a 'diagnostic triage tool' that can be performed quickly and at low cost on individual bone samples, in order to determine whether nDNA analysis is likely to be a viable option.


Subject(s)
Bone and Bones/chemistry , DNA/isolation & purification , Hot Temperature , Spectroscopy, Fourier Transform Infrared , Animals , Cattle , Cell Nucleus/genetics , DNA Degradation, Necrotic , DNA Primers , Electrophoresis, Agar Gel , Logistic Models , Polymerase Chain Reaction
10.
J Gen Virol ; 90(Pt 8): 1820-1826, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19357224

ABSTRACT

In this study, we characterized the full-length genomic sequences of 13 distinct hepatitis C virus (HCV) genotype 4 isolates/subtypes: QC264/4b, QC381/4c, QC382/4d, QC193/4g, QC383/4k, QC274/4l, QC249/4m, QC97/4n, QC93/4o, QC139/4p, QC262/4q, QC384/4r and QC155/4t. These were amplified, using RT-PCR, from the sera of patients now residing in Canada, 11 of which were African immigrants. The resulting genomes varied between 9421 and 9475 nt in length and each contains a single ORF of 9018-9069 nt. The sequences showed nucleotide similarities of 77.3-84.3 % in comparison with subtypes 4a (GenBank accession no. Y11604) and 4f (EF589160) and 70.6-72.8 % in comparison with genotype 1 (M62321/1a, M58335/1b, D14853/1c, and 1?/AJ851228) reference sequences. These similarities were often higher than those currently defined by HCV classification criteria for subtype (75.0-80.0 %) and genotype (67.0-70.0 %) division, respectively. Further analyses of the complete and partial E1 and partial NS5B sequences confirmed these 13 'provisionally assigned subtypes'.


Subject(s)
Genome, Viral , Hepacivirus/genetics , RNA, Viral/genetics , Sequence Analysis, DNA , Adult , Aged , Canada , Cluster Analysis , Emigrants and Immigrants , Female , Genotype , Hepacivirus/isolation & purification , Hepatitis C/virology , Humans , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Sequence Homology, Nucleic Acid , Serum/virology
11.
J Med Virol ; 80(8): 1370-8, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18551618

ABSTRACT

Infection with genotype 4 of the Hepatitis C virus is common in Africa and the Mediterranean area, but has also been found at increasing frequencies in injection drug users in Europe and North America. Full length viral sequences to characterize viral diversity and structure have recently become available mostly for subtype 4a, and studies in Egypt and Saudi Arabia, where high proportions of subtype 4a infected patients exist, have begun to establish optimized treatment regimens. However knowledge about other subtype variants of genotype 4 present in less developed African states is lacking. In this study the full coding region from so far poorly characterized variants of HCV genotype 4 was amplified and sequenced using a long range PCR technique. Sequences were analyzed with respect to phylogenetic relationship, possible recombination and prominent sequence characteristics compared to other known HCV strains. We present for the first time two full-length sequences from the HCV genotype 4k, in addition to five strains from HCV genotypes 4d and 4f. Reference sequences for accurate HCV genotyping are required for optimized treatment, and a better knowledge of the global viral sequence diversity is needed to guide vaccines or new drugs effective in the world wide epidemic.


Subject(s)
Hepacivirus/classification , Hepacivirus/genetics , Open Reading Frames/genetics , Amino Acid Sequence , Base Sequence , Genotype , Hepatitis C/virology , Humans , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction/methods , Recombination, Genetic , Reference Standards , Sequence Alignment , Sequence Analysis, DNA
12.
PLoS Pathog ; 3(3): e45, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17397261

ABSTRACT

CD8(+) cytotoxic T-lymphocytes (CTLs) perform a critical role in the immune control of viral infections, including those caused by human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV). As a result, genetic variation at CTL epitopes is strongly influenced by host-specific selection for either escape from the immune response, or reversion due to the replicative costs of escape mutations in the absence of CTL recognition. Under strong CTL-mediated selection, codon positions within epitopes may immediately "toggle" in response to each host, such that genetic variation in the circulating virus population is shaped by rapid adaptation to immune variation in the host population. However, this hypothesis neglects the substantial genetic variation that accumulates in virus populations within hosts. Here, we evaluate this quantity for a large number of HIV-1- (n > or = 3,000) and HCV-infected patients (n > or = 2,600) by screening bulk RT-PCR sequences for sequencing "mixtures" (i.e., ambiguous nucleotides), which act as site-specific markers of genetic variation within each host. We find that nonsynonymous mixtures are abundant and significantly associated with codon positions under host-specific CTL selection, which should deplete within-host variation by driving the fixation of the favored variant. Using a simple model, we demonstrate that this apparently contradictory outcome can be explained by the transmission of unfavorable variants to new hosts before they are removed by selection, which occurs more frequently when selection and transmission occur on similar time scales. Consequently, the circulating virus population is shaped by the transmission rate and the disparity in selection intensities for escape or reversion as much as it is shaped by the immune diversity of the host population, with potentially serious implications for vaccine design.


Subject(s)
Adaptation, Biological/genetics , HIV-1/genetics , Hepacivirus/genetics , Polymorphism, Genetic , CD8-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/virology , Epitopes, T-Lymphocyte , HIV Infections/pathology , HIV Infections/transmission , HIV-1/pathogenicity , Hepacivirus/pathogenicity , Hepatitis C/pathology , Hepatitis C/transmission , Humans , Models, Biological , Models, Theoretical , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction , Stochastic Processes
13.
Arch Gen Psychiatry ; 62(10): 1081-8, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16203953

ABSTRACT

CONTEXT: Traditionally, the search for genes involved in predisposition to major psychoses has proceeded with separate studies of schizophrenia and bipolar disorder. However, twin data suggest that, in addition to genes with specificity for these phenotypes, there exist genes that simultaneously influence susceptibility to schizophrenia, bipolar disorder, and schizoaffective disorder. OBJECTIVE: To undertake, to our knowledge, the first systematic search for such loci. DESIGN: Genomewide linkage scan. SETTING: Affected individuals were ascertained in the United Kingdom and Ireland from general psychiatric inpatient and outpatient services. PARTICIPANTS: The families were selected for linkage studies of either schizophrenia or bipolar disorder. Pedigrees were selected for the current analysis where there was at least 1 member with DSM-IV schizoaffective disorder, bipolar type. Within these pedigrees, individuals were coded as affected if they had been diagnosed with DSM-IV schizophrenia, schizoaffective disorder of bipolar type, or bipolar I disorder. A total of 24 pedigrees contributed 35 affected sibling pairs to the sample. METHOD: A 10-centimorgan genome scan using microsatellite markers was analyzed using MAPMAKER/SIBS software. RESULTS: A genomewide significant signal (LOD = 3.54) was observed at chromosome 1q42 (near D1S2800), and suggestive LOD scores were observed at chromosomes 22q11 (LOD = 1.96) and 19p13 (LOD = 1.85). No linkage was observed in these regions in our original schizophrenia or bipolar scans in individuals from the United Kingdom. CONCLUSIONS: Our linkage findings strongly support the existence of loci that influence susceptibility across the functional psychosis spectrum. The DISC1 gene lies within 2.5 megabases of our peak marker on chromosome 1q42 and has been previously implicated in schizophrenia, bipolar disorder, and, recently, schizoaffective disorder. Follow-up of this region should use samples enriched for cases of schizoaffective disorder. Our findings have similar implications for the search for genetic variation on chromosome 22q11 that influences susceptibility to psychosis.


Subject(s)
Chromosome Mapping/methods , Chromosomes, Human, Pair 19/genetics , Chromosomes, Human, Pair 1/genetics , Chromosomes, Human, Pair 22/genetics , Psychotic Disorders/genetics , Bipolar Disorder/genetics , Female , Genetic Markers/genetics , Genetic Predisposition to Disease/genetics , Genotype , Humans , Lod Score , Male , Microsatellite Repeats/genetics , Nerve Tissue Proteins/genetics , Pedigree , Schizophrenia/genetics , Sex Factors
14.
Am J Hum Genet ; 73(1): 49-62, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12802785

ABSTRACT

Genome scans of bipolar disorder (BPD) have not produced consistent evidence for linkage. The rank-based genome scan meta-analysis (GSMA) method was applied to 18 BPD genome scan data sets in an effort to identify regions with significant support for linkage in the combined data. The two primary analyses considered available linkage data for "very narrow" (i.e., BP-I and schizoaffective disorder-BP) and "narrow" (i.e., adding BP-II disorder) disease models, with the ranks weighted for sample size. A "broad" model (i.e., adding recurrent major depression) and unweighted analyses were also performed. No region achieved genomewide statistical significance by several simulation-based criteria. The most significant P values (<.01) were observed on chromosomes 9p22.3-21.1 (very narrow), 10q11.21-22.1 (very narrow), and 14q24.1-32.12 (narrow). Nominally significant P values were observed in adjacent bins on chromosomes 9p and 18p-q, across all three disease models on chromosomes 14q and 18p-q, and across two models on chromosome 8q. Relatively few BPD pedigrees have been studied under narrow disease models relative to the schizophrenia GSMA data set, which produced more significant results. There was no overlap of the highest-ranked regions for the two disorders. The present results for the very narrow model are promising but suggest that more and larger data sets are needed. Alternatively, linkage might be detected in certain populations or subsets of pedigrees. The narrow and broad data sets had considerable power, according to simulation studies, but did not produce more highly significant evidence for linkage. We note that meta-analysis can sometimes provide support for linkage but cannot disprove linkage in any candidate region.


Subject(s)
Bipolar Disorder/genetics , Genome, Human , Schizophrenia/genetics , Humans
SELECTION OF CITATIONS
SEARCH DETAIL
...