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Journal of Assisted Reproduction and... Sep 2016This is a comprehensive review of the literature in this field attempting to put the FMR1 gene and its evaluation into context, both in general and for the reproductive... (Review)
Review
PURPOSE
This is a comprehensive review of the literature in this field attempting to put the FMR1 gene and its evaluation into context, both in general and for the reproductive health audience.
METHODS
Online database search of publications with systematic review of all papers relevant to ovarian reserve and assisted reproduction was done.
RESULTS
Relevant papers were identified and assessed, and an attempt was made to understand, rationalize and explain the divergent views in this field of study. Seminal and original illustrations were employed.
CONCLUSIONS
FMR1 is a highly conserved gene whose interpretation and effect on outcomes remains controversial in the reproductive health setting. Recent re-evaluations of the commonly accepted normal range have yielded interesting tools for possibly explaining unexpected outcomes in assisted reproduction. Fragile X investigations should perhaps become more routinely assessed in the reproductive health setting, particularly following a failed treatment cycle where oocyte quality is thought to be a contributing factor, or in the presence of a surprise finding of diminished ovarian reserve in a young patient.
Topics: Female; Fragile X Mental Retardation Protein; Humans; Mutation; Ovarian Reserve; Reproduction; Reproductive Techniques, Assisted
PubMed: 27432256
DOI: 10.1007/s10815-016-0765-6 -
Molecular and Clinical Oncology Jun 2016Previous evidence suggests that the accumulation of the hepatitis B virus (HBV) X gene region point mutations may be associated with the development of hepatocellular...
Previous evidence suggests that the accumulation of the hepatitis B virus (HBV) X gene region point mutations may be associated with the development of hepatocellular carcinoma (HCC). However, the pathogenesis of HCC remains to be elucidated. The aim of the present meta-analysis was to investigate the association between the HBV X gene point mutations and the risk of HCC. Studies were collected regarding the association between HBV X gene point mutations and the risk of HCC, which were identified in PubMed, EMBASE and China National Knowledge Infrastructure databases. The results were evaluated by use of odds ratios (ORs) and its 95% confidence intervals (CIs), which were pooled by random or fixed effects. A total of 11 studies involving 2,502 patients were included in this meta-analysis. Statistical summary ORs of HBV X gene point mutations were obtained for T1653 (OR, 3.11; 95% CI, 2.22-4.36), V1753 (OR, 2.55; 95% CI, 1.66-3.92), and T1762/A1764 (OR, 4.49; 95% CI, 2.86-7.07). HBV X gene point mutations T1653, V1753 and T1762/A1764 could increase the risk of HCC significantly, particularly the T1762/A1764 double mutations. These mutations may be predictive for hepatocarcinogenesis. However, these results of the meta-analysis should be treated carefully due to a low level of evidence.
PubMed: 27284442
DOI: 10.3892/mco.2016.847 -
PloS One 2016Mutations in granulin (PGRN) and tau (MAPT), and hexanucleotide repeat expansions near the C9orf72 genes are the most prevalent genetic causes of frontotemporal lobar... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Mutations in granulin (PGRN) and tau (MAPT), and hexanucleotide repeat expansions near the C9orf72 genes are the most prevalent genetic causes of frontotemporal lobar degeneration. Although behavior, language and movement presentations are common, the relationship between genetic subgroup and movement disorder phenomenology is unclear.
OBJECTIVE
We conducted a systematic review and meta-analysis of the literature characterizing the spectrum and prevalence of movement disorders in genetic frontotemporal lobar degeneration.
METHODS
Electronic databases were searched using terms related to frontotemporal lobar degeneration and movement disorders. Articles were included when cases had a proven genetic cause. Study-specific prevalence estimates for clinical features were transformed using Freeman-Tukey arcsine transformation, allowing for pooled estimates of prevalence to be generated using random-effects models.
RESULTS
The mean age at onset was earlier in those with MAPT mutations compared to PGRN (p<0.001) and C9orf72 (p = 0.024). 66.5% of subjects had an initial non-movement presentation that was most likely a behavioral syndrome (35.7%). At any point during the disease, parkinsonism was the most common movement syndrome reported in 79.8% followed by progressive supranuclear palsy (PSPS) and corticobasal (CBS) syndromes in 12.2% and 10.7%, respectively. The prevalence of movement disorder as initial presentation was higher in MAPT subjects (35.8%) compared to PGRN subjects (10.1). In those with a non-movement presentation, language disorder was more common in PGRN subjects (18.7%) compared to MAPT subjects (5.4%).
SUMMARY
This represents the first systematic review and meta-analysis of the occurrence of movement disorder phenomenology in genetic frontotemporal lobar degeneration. Standardized prospective collection of clinical information in conjunction with genetic characterization will be crucial for accurate clinico-genetic correlation.
Topics: Age of Onset; Frontotemporal Lobar Degeneration; Humans; Intercellular Signaling Peptides and Proteins; Movement Disorders; Mutation; Progranulins; tau Proteins
PubMed: 27100392
DOI: 10.1371/journal.pone.0153852 -
PloS One 2016To compare the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis against healthy controls, and evaluate... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To compare the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis against healthy controls, and evaluate geographical variations.
DESIGN
Systematic review and meta-analysis of case control studies.
METHODS
We conducted a systematic review of electronic databases including MEDLINE and EMBASE. The main outcome was the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis; we also analyzed individual country variations in the prevalence. The random-effects model OR was used as the primary outcome measure.
RESULTS
In total 19 studies evaluated 868 cases of cerebral venous thrombosis and 3981 controls. Prothrombin G20210A was found in 103/868 of the patients with cerebral venous thrombosis and 105/3999 of the healthy controls [random effects pooled OR 5.838, 95% CI 3.96 to 8.58; I217.9%]. The prevalence of prothrombin G20210A was significantly elevated in Italian studies (OR 9.69), in Brazilian studies (OR 7.02), and in German studies (OR 3.77), but not in Iranian studies (OR 0.98).
CONCLUSION
Prothrombin G20210A is significantly associated with cerebral venous thrombosis when compared to healthy controls, although this association is highly dependent on the country of origin.
Topics: Brazil; Case-Control Studies; Cerebral Veins; Gene Frequency; Germany; Humans; Iran; Italy; Linkage Disequilibrium; Odds Ratio; Point Mutation; Prevalence; Prothrombin; Venous Thrombosis
PubMed: 27031503
DOI: 10.1371/journal.pone.0151607 -
Oncotarget Nov 2015The prevalence of global obesity is increasing. Obesity is associated with general cancer-related morbidity and mortality and is a known risk factor for development of... (Review)
Review
The prevalence of global obesity is increasing. Obesity is associated with general cancer-related morbidity and mortality and is a known risk factor for development of specific cancers. A recent large systematic review of 24 studies based on meta-analysis of 11,149 patients with prostate cancer showed a significant correlation between obesity and the risk of advanced prostate cancer. Further, a sustained reduction in BMI correlates with a decreased risk of developing aggressive disease. On the other hand, the correlation between consuming different products and prostate cancer occurrence/risk is limited.Here, we review the role of adipose tissue from an endocrine perspective and outline the effect of adipokines on cancer metabolism, with particular focus on leptin. Leptin exerts its physiological and pathological effects through modification of intracellular signalling, most notably activating the Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 3 pathway and recently shown sphingolipid pathway. Both high levels of leptin in circulation and leptin receptor mutation are associated with prostate cancer risk in human patients; however, the in vivo mechanistic evidence is less conclusive.Given the complexity of metabolic cancer pathways, it is possible that leptin may have varying effects on prostate cancer at different stages of its development, a point that may be addressed by further epidemiological studies.
Topics: Adipose Tissue; Animals; Carcinogenesis; Genetic Predisposition to Disease; Humans; Janus Kinases; Leptin; Male; Obesity; Polymorphism, Genetic; Prostatic Neoplasms; Receptors, Leptin; STAT3 Transcription Factor; Signal Transduction
PubMed: 26376613
DOI: 10.18632/oncotarget.5574 -
Tropical Medicine & International... Sep 2014Cotrimoxazole prophylactic treatment (CPT) prevents opportunistic infections in HIV-infected or HIV-exposed children, but estimates of the effectiveness in preventing... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
Cotrimoxazole prophylactic treatment (CPT) prevents opportunistic infections in HIV-infected or HIV-exposed children, but estimates of the effectiveness in preventing malaria vary. We reviewed studies that examined the effect of CPT on incidence of malaria in children in sub-Saharan Africa.
METHODS
We searched PubMed and EMBASE for randomised controlled trials (RCTs) and cohort studies on the effect of CPT on incidence of malaria and mortality in children and extracted data on the prevalence of sulphadoxine-pyrimethamine resistance-conferring point mutations. Incidence rate ratios (IRR) from individual studies were combined using random effects meta-analysis; confounder-adjusted estimates were used for cohort studies. The importance of resistance was examined in meta-regression analyses.
RESULTS
Three RCTs and four cohort studies with 5039 children (1692 HIV-exposed; 2800 HIV-uninfected; 1486 HIV-infected) were included. Children on CPT were less likely to develop clinical malaria episodes than those without prophylaxis (combined IRR 0.37, 95% confidence interval: 0.21-0.66), but there was substantial between-study heterogeneity (I-squared = 94%, P < 0.001). The protective efficacy of CPT was highest in an RCT from Mali, where the prevalence of antifolate resistant plasmodia was low. In meta-regression analyses, there was some evidence that the efficacy of CPT declined with increasing levels of resistance. Mortality was reduced with CPT in an RCT from Zambia, but not in a cohort study from Côte d'Ivoire.
CONCLUSIONS
Cotrimoxazole prophylactic treatment reduces incidence of malaria and mortality in children in sub-Saharan Africa, but study designs, settings and results were heterogeneous. CPT appears to be beneficial for HIV-infected and HIV-exposed as well as HIV-uninfected children.
Topics: Africa South of the Sahara; Antimalarials; Child; Drug Combinations; Drug Resistance; HIV Infections; Humans; Malaria; Mutation; Pyrimethamine; Sulfadoxine; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 25039469
DOI: 10.1111/tmi.12352 -
Journal of the International AIDS... 2014There are 31 million adults living with HIV-1 non-B subtypes globally, and about 10 million are on antiretroviral therapy (ART). Global evidence to guide clinical... (Review)
Review
There are 31 million adults living with HIV-1 non-B subtypes globally, and about 10 million are on antiretroviral therapy (ART). Global evidence to guide clinical practice on ART response in HIV-1 non-B subtypes remains limited. We systematically searched 11 databases for the period 1996 to 2013 for evidence. Outcomes documented included time to development of AIDS and/or death, resistance mutations, opportunistic infections, and changes in CD4 cell counts and viral load. A lack of consistent reporting of all clinical end points precluded a meta-analysis. In sum, genetic diversity that precipitated differences in disease progression in ART-naïve populations was minimized in ART-experienced populations, although variability in resistance mutations persisted across non-B subtypes. To improve the quality of patient care in global settings, recording HIV genotypes at baseline and at virologic failure with targeted non-B subtype-based point-of-care resistance assays and timely phasing out of resistance-inducing ART regimens is recommended.
Topics: Anti-HIV Agents; Disease Progression; Drug Resistance, Viral; HIV Infections; HIV-1; Humans; Mutation; Treatment Outcome
PubMed: 24998532
DOI: 10.7448/IAS.17.1.18944 -
The Journal of Antimicrobial... Feb 2014Improving our understanding of the relationship between the genotype and the drug resistance phenotype of Mycobacterium tuberculosis will aid the development of more... (Review)
Review
BACKGROUND
Improving our understanding of the relationship between the genotype and the drug resistance phenotype of Mycobacterium tuberculosis will aid the development of more accurate molecular diagnostics for drug-resistant tuberculosis. Studies that use direct genetic manipulation to identify the mutations that cause M. tuberculosis drug resistance are superior to associational studies in elucidating an individual mutation's contribution to the drug resistance phenotype.
METHODS
We systematically reviewed the literature for publications reporting allelic exchange experiments in any of the resistance-associated M. tuberculosis genes. We included studies that introduced single point mutations using specialized linkage transduction or site-directed/in vitro mutagenesis and documented a change in the resistance phenotype.
RESULTS
We summarize evidence supporting the causal relationship of 54 different mutations in eight genes (katG, inhA, kasA, embB, embC, rpoB, gyrA and gyrB) and one intergenic region (furA-katG) with resistance to isoniazid, the rifamycins, ethambutol and fluoroquinolones. We observed a significant role for the strain genomic background in modulating the resistance phenotype of 21 of these mutations and found examples of where the same drug resistance mutations caused varying levels of resistance to different members of the same drug class.
CONCLUSIONS
This systematic review highlights those mutations that have been shown to causally change phenotypic resistance in M. tuberculosis and brings attention to a notable lack of allelic exchange data for several of the genes known to be associated with drug resistance.
Topics: Alleles; Animals; Antitubercular Agents; Humans; Mutation; Mycobacterium tuberculosis; Tuberculosis, Multidrug-Resistant
PubMed: 24055765
DOI: 10.1093/jac/dkt358 -
Current Genomics Apr 2011Hepatocellular carcinoma (HCC) is the third most common cause of cancer deaths worldwide, and the incidence of this fatal disease is still on rise. The majority of HCCs...
Hepatocellular carcinoma (HCC) is the third most common cause of cancer deaths worldwide, and the incidence of this fatal disease is still on rise. The majority of HCCs emerge in the background of a chronic liver disease, such as chronic hepatitis and liver cirrhosis. The current understanding is that majority of HCCs evolve as a consequence of chronic inflammation and due to the presence of infection with hepatitis viruses. These underlying pathogenic stimuli subsequently induce a spectrum of genetic and epigenetic alterations in several cancer-related genes, which are involved in cell-cycle regulation, cell growth and adhesion. Such widespread genomic alterations cause disruption of normal cellular signaling and finally lead to the acquisition of a malignant phenotype in HCC. In general, the type of gene alterations, such as point mutations, deletion of chromosomal regions and abnormal methylation of gene promoters differ according to the individual targeted gene. In HCC, incidence of genetic alterations is relatively rare and is limited to a subset of few cancer-specific genes, such as the tumor suppressor p53, RB genes and oncogenes such as the CTNNB1. In contrast, epigenetic changes that involve aberrant methylation of genes and other post-transcriptional histone modifications occur far more frequently, and some of these epigenetic alterations are now being exploited for the development of molecular diagnostic signatures for HCC. In addition, recent findings of unique microRNA expression profiles also provide an evidence for the existence of novel mechanisms for gene expression regulation in HCC. In this review article, we will review the current state of knowledge on the activation of various oncogenic pathways and the inactivation of tumor suppressor pathways in HCC that result in the disruption of cancer-related gene function. In addition, we will specifically emphasize the clinical implication of some of these genetic and epigenetic alterations in the management of hepatocarcinogenesis.
PubMed: 21966251
DOI: 10.2174/138920211795564359 -
Blood May 2009Recent studies suggested that JAK2V617F mutation is frequent in patients with splanchnic vein thrombosis (SVT) but not in patients with other venous thromboembolic... (Meta-Analysis)
Meta-Analysis
Recent studies suggested that JAK2V617F mutation is frequent in patients with splanchnic vein thrombosis (SVT) but not in patients with other venous thromboembolic events (VTE). However, whether screening for the JAK2V617F mutation in VTE patients is justified remains unclear. Therefore, we performed a systematic review to assess the frequency of JAK2 mutation in VTE patients and the role of JAK2V617F mutation in the diagnosis of myeloproliferative neoplasms. MEDLINE and EMBASE databases were searched. Two reviewers independently performed study selection and extracted study characteristics. Pooled odds ratios of case-control studies and weighted mean proportion of the prevalence of JAK2V617F mutation of uncontrolled series were calculated. Twenty-four studies involving 3123 patients were included. Mean prevalence of JAK2 mutation was 32.7% (95% confidence interval, 25.5%-35.9%) in SVT patients. JAK2 mutation was associated with increased risk of SVT (odds ratio, 53.98; 95% confidence interval, 13.10-222.45). Mean prevalence of JAK2 mutation in other VTE patients was low (range, 0.88%-2.57%). Presence of JAK2V617F mutation in SVT patients was associated with a subsequent diagnosis of myeloproliferative neoplasm in many patients. JAK2 mutation is strongly associated with SVT, and routine screening of JAK2 mutation appears to be indicated in these patients.
Topics: Algorithms; Amino Acid Substitution; Biomarkers, Tumor; Case-Control Studies; Early Detection of Cancer; Female; Gene Frequency; Humans; Janus Kinase 2; Male; Myeloproliferative Disorders; Neoplasms; Phenylalanine; Philadelphia Chromosome; Point Mutation; Valine; Venous Thromboembolism
PubMed: 19273837
DOI: 10.1182/blood-2008-12-196014