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1.
J Intensive Care Med ; : 8850666241245364, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602137

RESUMO

Background: Helicobacter pylori is implicated in the development of gastritis, ulcers, and various gastric cancers, representing significant morbidity, mortality, and healthcare spending. Patients with H. pylori infection have traditionally been treated with oral antibiotics, however, oral therapy is not feasible in all clinical situations. We examined the available evidence supporting the use of intravenous (IV) antibiotics in H. pylori. Methods: This systematic review was carried out by reviewing multiple electronic databases: MEDLINE, CENTRAL, EMBASE, CINAHL, Clinicaltrials.org, and the World Health Organization (WHO) database of clinical trials. Articles published from database inception until February 12, 2023 that discussed the use of IV antibiotics in H. pylori management were included. Results: The search strategy identified 978 studies, with 11 meeting the inclusion criteria. The results demonstrate that there is a lack of robust trials examining the use of IV antibiotics in H. pylori management. Many trials demonstrated that IV antibiotics were safe and efficacious but the results are limited by inconsistencies in the year and geographic location trials were conducted, the IV and oral antibiotic regimens, and the duration of therapy. Conclusions: IV antibiotics appear to be a feasible therapeutic alternative in the management of H. pylori and can be considered, especially in patient populations where oral therapy is contraindicated.

2.
J Virol ; 97(2): e0160022, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36757205

RESUMO

Infection by Kaposi sarcoma-associated herpesvirus (KSHV) can cause severe consequences, such as cancers and lymphoproliferative diseases. Whole inactivated viruses (WIV) with chemically destroyed genetic materials have been used as antigens in several licensed vaccines. During KSHV productive replication, virus-like vesicles (VLVs) that lack capsids and viral genomes are generated along with virions. Here, we investigated the immunogenicity of KSHV VLVs produced from a viral mutant that was defective in capsid formation and DNA packaging. Mice immunized with adjuvanted VLVs generated KSHV-specific T cell and antibody responses. Neutralization of KSHV infection by the VLV immune serum was low but was markedly enhanced in the presence of the complement system. Complement-enhanced neutralization and complement deposition on KSHV-infected cells was dependent on antibodies targeting viral open reading frame 4 (ORF4). However, limited complement-mediated enhancement was detected in the sera of a small cohort of KSHV-infected humans which contained few neutralizing antibodies. Therefore, vaccination that induces antibody effector functions can potentially improve infection-induced humoral immunity. Overall, our study highlights a potential benefit of engaging complement-mediated antibody functions in future KSHV vaccine development. IMPORTANCE KSHV is a virus that can lead to cancer after infection. A vaccine that prevents KSHV infection or transmission would be helpful in preventing the development of these cancers. We investigated KSHV VLV as an immunogen for vaccination. We determined that antibodies targeting the viral protein ORF4 induced by VLV immunization could engage the complement system and neutralize viral infection. However, ORF4-specific antibodies were seldom detected in the sera of KSHV-infected humans. Moreover, these human sera did not potently trigger complement-mediated neutralization, indicating an improvement that immunization can confer. Our study suggests a new antibody-mediated mechanism to control KSHV infection and underscores the benefit of activating the complement system in a future KSHV vaccine.


Assuntos
Anticorpos Neutralizantes , Herpesvirus Humano 8 , Animais , Humanos , Camundongos , Anticorpos Neutralizantes/imunologia , Infecções por Herpesviridae , Herpesvirus Humano 8/imunologia , Fases de Leitura Aberta/imunologia , Vacinação , Proteínas Virais/imunologia
3.
Cells ; 12(2)2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36672230

RESUMO

Humoral immune response is important in fighting pathogens by the production of specific antibodies by B cells. In germinal centers, T follicular helper (TFH) cells provide important help to B-cell antibody production but also contribute to HIV persistence. T follicular regulatory (TFR) cells, which inhibit the function of TFH cells, express similar surface markers. Since FOXP3 is the only marker that distinguishes TFR from TFH cells it is unknown whether the increase in TFH cells observed in HIV infection and HIV persistence may be partly due to an increase in TFR cells. Using multicolor flow cytometry to detect TFH and TFR cells in cryopreserved peripheral blood mononuclear cells from HIV-infected and non-infected participants in the UCLA Multicenter AIDS Cohort Study (MACS), we identified CD3+CXCR5+CD4+CD8-BCL6+ peripheral blood TFH (pTFH) cells and CD3+CXCR5+CD4+CD8-FOXP3+ peripheral blood TFR (pTFR) cells. Unlike TFR cells in germinal centers, pTFR cells do not express B cell lymphoma 6 (BCL6), a TFH cell master transcriptional regulator. Our major findings are that the frequency of pTFH cells, but not pTFR cells was higher in HIV-infected participants of the MACS and that pTFH cells expressed less CCR5 in HIV-infected MACS participants. Constitutive expression of CCR5 in TFR cells supports their potential to contribute to HIV persistence.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Células T Auxiliares Foliculares/metabolismo , Infecções por HIV/metabolismo , Linfócitos T Auxiliares-Indutores , Estudos de Coortes , Leucócitos Mononucleares/metabolismo , Síndrome da Imunodeficiência Adquirida/metabolismo , Fatores de Transcrição Forkhead/metabolismo
4.
J Clin Invest ; 132(16)2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35653193

RESUMO

Purine nucleoside phosphorylase (PNP) enables the breakdown and recycling of guanine nucleosides. PNP insufficiency in humans is paradoxically associated with both immunodeficiency and autoimmunity, but the mechanistic basis for these outcomes is incompletely understood. Here, we identify two immune lineage-dependent consequences of PNP inactivation dictated by distinct gene interactions. During T cell development, PNP inactivation is synthetically lethal with downregulation of the dNTP triphosphohydrolase SAMHD1. This interaction requires deoxycytidine kinase activity and is antagonized by microenvironmental deoxycytidine. In B lymphocytes and macrophages, PNP regulates Toll-like receptor 7 signaling by controlling the levels of its (deoxy)guanosine nucleoside ligands. Overriding this regulatory mechanism promotes germinal center formation in the absence of exogenous antigen and accelerates disease in a mouse model of autoimmunity. This work reveals that one purine metabolism gene protects against immunodeficiency and autoimmunity via independent mechanisms operating in distinct immune lineages and identifies PNP as a potentially novel metabolic immune checkpoint.


Assuntos
Síndromes de Imunodeficiência , Purina-Núcleosídeo Fosforilase , Animais , Autoimunidade , Humanos , Camundongos , Nucleosídeos de Purina , Purina-Núcleosídeo Fosforilase/genética , Purina-Núcleosídeo Fosforilase/metabolismo , Linfócitos T , Receptor 7 Toll-Like
5.
Front Cardiovasc Med ; 8: 650852, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026870

RESUMO

Background: There is a bidirectional relationship between blood pressure variability (BPV) and anxiety, but few studies have examined the gender- and age-specific effects of visit-to-visit BPV on incident anxiety. We examined the predictive value of BPV for the incidence of anxiety in a family clinic cohort. Methods: Consecutive patients with a first attendance to family medicine clinics in Hong Kong between January 1, 2000, and December 31, 2002, with at least three blood pressure measurements available thereafter were included. The primary endpoint was incident anxiety as identified by ICD-9 coding. Results: This study included 48,023 (50% males) patients with a median follow-up of 224 [interquartile range (IQR): 217-229] months. Females were more likely to develop incident anxiety compared to males (incidence rate: 7 vs. 2%), as were patients of older age. Significant univariate predictors were female gender, older age, preexisting cardiovascular diseases, respiratory diseases, diabetes mellitus, hypertension, and gastrointestinal diseases, various laboratory examinations, and the number of blood pressure measurements. Higher baseline, maximum, minimum, standard deviation (SD), coefficient of variation (CV), and variability score of diastolic blood pressure significantly predicted incident anxiety, as did all systolic blood pressure measures [baseline, latest, maximum, minimum, mean, median, variance, SD, root mean square (RMS), CV, and variability score]. Conclusions: The relationships between longer-term visit-to-visit BPV and incident anxiety were identified. Female and older patients with higher blood pressure and higher BPV were at the highest risks of incident anxiety.

6.
NPJ Vaccines ; 5(1): 102, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33298958

RESUMO

Vaccines based on live attenuated viruses often induce broad, multifaceted immune responses. However, they also usually sacrifice immunogenicity for attenuation. It is particularly difficult to elicit an effective vaccine for herpesviruses due to an armament of immune evasion genes and a latent phase. Here, to overcome the limitation of attenuation, we developed a rational herpesvirus vaccine in which viral immune evasion genes were deleted to enhance immunogenicity while also attaining safety. To test this vaccine strategy, we utilized murine gammaherpesvirus-68 (MHV-68) as a proof-of-concept model for the cancer-associated human γ-herpesviruses, Epstein-Barr virus and Kaposi sarcoma-associated herpesvirus. We engineered a recombinant MHV-68 virus by targeted inactivation of viral antagonists of type I interferon (IFN-I) pathway and deletion of the latency locus responsible for persistent infection. This recombinant virus is highly attenuated with no measurable capacity for replication, latency, or persistence in immunocompetent hosts. It stimulates robust innate immunity, differentiates virus-specific memory T cells, and elicits neutralizing antibodies. A single vaccination affords durable protection that blocks the establishment of latency following challenge with the wild type MHV-68 for at least six months post-vaccination. These results provide a framework for effective vaccination against cancer-associated herpesviruses through the elimination of latency and key immune evasion mechanisms from the pathogen.

7.
J Clin Neurosci ; 67: 263-265, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31248785

RESUMO

Isolated traumatic medial rectus palsies associated with closed head injury is rarely reported in literature. We report the case of a 48 year-old male with an isolated right medial rectus palsy following a mechanical fall with occipital headstrike. Bifrontal and bitemporal haemorrhagic contusions were seen on computed tomography (CT). Magnetic resonance imaging (MRI) revealed a T2 hyperintense lesion at the right paramedian dorsal midbrain, with changes on diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC), suggestive of ischaemic changes in the oculomotor nucleus. He was followed up at two- and six-weeks.


Assuntos
Traumatismos Cranianos Fechados/diagnóstico , Músculos Oculomotores/fisiopatologia , Paralisia/diagnóstico , Imagem de Difusão por Ressonância Magnética , Traumatismos Cranianos Fechados/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Mesencéfalo/diagnóstico por imagem , Pessoa de Meia-Idade , Paralisia/etiologia , Tomografia Computadorizada por Raios X
8.
Mol Genet Metab ; 124(2): 114-123, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29724658

RESUMO

The transplantation, engraftment, and expansion of primary hepatocytes have the potential to be an effective therapy for metabolic disorders of the liver including those of nitrogen metabolism. To date, such methods for the treatment of urea cycle disorders in murine models has only been minimally explored. Arginase deficiency, an inherited disorder of nitrogen metabolism that presents in the first two years of life, has the potential to be treated by such methods. To explore the potential of this approach, we mated the conditional arginase deficient mouse with a mouse model deficient in fumarylacetoacetate hydrolase (FAH) and with Rag2 and IL2-Rγ mutations to give a selective advantage to transplanted (normal) human hepatocytes. On day -1, a uroplasminogen-expressing adenoviral vector was administered intravenously followed the next day with the transplantation of 1 × 106 human hepatocytes (or vehicle alone) by intrasplenic injection. As the initial number of administered hepatocytes would be too low to prevent hepatotoxicity-induced mortality, NTBC cycling was performed to allow for hepatocyte expansion and repopulation. While all control mice died, all except one human hepatocyte transplanted mice survived. Four months after hepatocyte transplantation, 2 × 1011 genome copies of AAV-TBG-Cre recombinase was administered IV to disrupt endogenous hepatic arginase expression. While all control mice died within the first month, human hepatocyte transplanted mice did well. Ammonia and amino acids, analyzed in both groups before and after disruption of endogenous arginase expression, while well-controlled in the transplanted group, were markedly abnormal in the controls. Ammonium challenging further demonstrated the durability and functionality of the human repopulated liver. In conclusion, these studies demonstrate that human hepatocyte repopulation in the murine liver can result in effective treatment of arginase deficiency.


Assuntos
Arginase/fisiologia , Predisposição Genética para Doença , Hepatócitos/transplante , Hepatopatias/terapia , Doenças Metabólicas/terapia , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Hepatócitos/citologia , Humanos , Hepatopatias/enzimologia , Hepatopatias/patologia , Masculino , Doenças Metabólicas/enzimologia , Doenças Metabólicas/patologia , Camundongos , Camundongos Knockout
9.
Mol Ther Nucleic Acids ; 5(11): e394, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27898091

RESUMO

Urea cycle disorders are incurable enzymopathies that affect nitrogen metabolism and typically lead to hyperammonemia. Arginase deficiency results from a mutation in Arg1, the enzyme regulating the final step of ureagenesis and typically results in developmental disabilities, seizures, spastic diplegia, and sometimes death. Current medical treatments for urea cycle disorders are only marginally effective, and for proximal disorders, liver transplantation is effective but limited by graft availability. Advances in human induced pluripotent stem cell research has allowed for the genetic modification of stem cells for potential cellular replacement therapies. In this study, we demonstrate a universally-applicable CRISPR/Cas9-based strategy utilizing exon 1 of the hypoxanthine-guanine phosphoribosyltransferase locus to genetically modify and restore arginase activity, and thus ureagenesis, in genetically distinct patient-specific human induced pluripotent stem cells and hepatocyte-like derivatives. Successful strategies restoring gene function in patient-specific human induced pluripotent stem cells may advance applications of genetically modified cell therapy to treat urea cycle and other inborn errors of metabolism.

11.
J Cell Sci ; 127(Pt 20): 4531-41, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25146393

RESUMO

Here, we report the impact of redox potential on isolated cardiac ryanodine receptor (RyR2) channel activity and its response to physiological changes in luminal [Ca(2+)]. Basal leak from the sarcoplasmic reticulum is required for normal Ca(2+) handling, but excess diastolic Ca(2+) leak attributed to oxidative stress is thought to lower the threshold of RyR2 for spontaneous sarcoplasmic reticulum Ca(2+) release, thus inducing arrhythmia in pathological situations. Therefore, we examined the RyR2 response to luminal [Ca(2+)] under reducing or oxidising cytoplasmic redox conditions. Unexpectedly, as luminal [Ca(2+)] increased from 0.1 to 1.5 mM, RyR2 activity declined when pretreated with cytoplasmic 1 mM DTT or buffered with GSH∶GSSG to a normal reduced cytoplasmic redox potential (-220 mV). Conversely, with 20 µM cytoplasmic 4,4'-DTDP or buffering of the redox potential to an oxidising value (-180 mV), RyR2 activity increased with increasing luminal [Ca(2+)]. The luminal redox potential was constant at -180 mV in each case. These responses to luminal [Ca(2+)] were maintained with cytoplasmic 2 mM Na2ATP or 5 mM MgATP (1 mM free Mg(2+)). Overall, the results suggest that the redox potential in the RyR2 junctional microdomain is normally more oxidised than that of the bulk cytoplasm.


Assuntos
Arritmias Cardíacas/metabolismo , Citoplasma/metabolismo , Microdomínios da Membrana/metabolismo , Miócitos Cardíacos/fisiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Células Cultivadas , Microambiente Celular , Cães , Potenciais da Membrana , Oxirredução , Estresse Oxidativo , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Ovinos
12.
Mol Pharmacol ; 86(4): 438-49, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25106424

RESUMO

The use of anthracycline chemotherapeutic drugs is restricted owing to potentially fatal cardiotoxic side effects. It has been hypothesized that anthracycline metabolites have a primary role in this cardiac dysfunction; however, information on the molecular interactions of these compounds in the heart is scarce. Here we provide novel evidence that doxorubicin and its metabolite, doxorubicinol, bind to the cardiac ryanodine receptor (RyR2) and to the sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA2A) and deleteriously alter their activity. Both drugs (0.01 µM-2.5 µM) activated single RyR2 channels, and this was reversed by drug washout. Both drugs caused a secondary inhibition of RyR2 activity that was not reversed by drug washout. Preincubation with the reducing agent dithiothreitol (DTT, 1 mM) prevented drug-induced inhibition of channel activity. Doxorubicin and doxorubicinol reduced the abundance of thiol groups on RyR2, further indicating that oxidation reactions may be involved in the actions of the compounds. Ca(2+) uptake into sarcoplasmic reticulum vesicles by SERCA2A was inhibited by doxorubicinol, but not doxorubicin. Unexpectedly, in the presence of DTT, doxorubicinol enhanced the rate of Ca(2+) uptake by SERCA2A. Together the evidence provided here shows that doxorubicin and doxorubicinol interact with RyR2 and SERCA2A in similar ways, but that the metabolite acts with greater efficacy than the parent compound. Both compounds modify RyR2 and SERCA2A activity by binding to the proteins and also act via thiol oxidation to disrupt SR Ca(2+) handling. These actions would have severe consequences on cardiomyocyte function and contribute to clinical symptoms of acute anthracycline cardiotoxicity.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Doxorrubicina/análogos & derivados , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Cálcio/metabolismo , Cardiotoxinas/farmacologia , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacologia , Bicamadas Lipídicas/metabolismo , Ligação Proteica , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Ovinos
13.
Am J Physiol Regul Integr Comp Physiol ; 303(10): R1011-22, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23019212

RESUMO

Orexin neurons form a restricted group in the dorsal hypothalamus. The group is centered on the perifornical area within the classic hypothalamic defense area, an area which when activated produces marked cardiovascular and respiratory effects. Central administration of orexin can produce cardiorespiratory effects, but the extent to which orexin contributes to such responses evoked from the perifornical hypothalamus is not clear. To determine this, we used the dual orexin receptor antagonist Almorexant to challenge the cardiorespiratory effects evoked by disinhibition of the perifornical hypothalamus. Bicuculline (10 and 20 pmol) was microinjected in the perifornical area before and after administration of Almorexant (15 mg/kg iv) or vehicle in urethane-anesthetized rats. Almorexant significantly reduced the pressor, tachycardic, renal sympathoexcitatory, and tachypneic responses to bicuculline (10 pmol, by 55%, 53%, 28%, 77%; 20 pmol, by 54%, 27%, 51%, 72%, respectively). Reductions of similar magnitude were observed with bicuculline microinjections centered on more caudal sites just peripheral to the orexin neuron group, which would likely have activated fewer orexin neurons. In contrast, Almorexant had no effect on the cardiorespiratory response of the chemoreflex (sodium cyanide injection) or the sympathetic component of the baroreflex. Thus orexin makes a major contribution to the cardiorespiratory response evoked from the perifornical area even though orexin neurons represent only a fraction of the output of this area. Orexin neurons may also mediate cardiorespiratory responses from non-orexin neurons in the caudal hypothalamus. However, under resting conditions, blockade of orexin receptors does not affect the chemo- and baroreflexes.


Assuntos
Acetamidas/farmacologia , Barorreflexo/efeitos dos fármacos , Células Quimiorreceptoras/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Isoquinolinas/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Neuropeptídeos/antagonistas & inibidores , Animais , Bicuculina/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Receptores de GABA-A/farmacologia , Hipotálamo/fisiologia , Masculino , Receptores de Orexina , Ratos , Ratos Sprague-Dawley
14.
Hum Mol Genet ; 21(20): 4497-507, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22814392

RESUMO

Chloride intracellular channel 2 (CLIC2) protein is a member of the glutathione transferase class of proteins. Its' only known function is the regulation of ryanodine receptor (RyR) intracellular Ca(2+) release channels. These RyR proteins play a major role in the regulation of Ca(2+) signaling in many cells. Utilizing exome capture and deep sequencing of genes on the X-chromosome, we have identified a mutation in CLIC2 (c.303C>G, p.H101Q) which is associated with X-linked intellectual disability (ID), atrial fibrillation, cardiomegaly, congestive heart failure (CHF), some somatic features and seizures. Functional studies of the H101Q variant indicated that it stimulated rather than inhibited the action of RyR channels, with channels remaining open for longer times and potentially amplifying Ca(2+) signals dependent on RyR channel activity. The overly active RyRs in cardiac and skeletal muscle cells and neuronal cells would result in abnormal cardiac function and trigger post-synaptic pathways and neurotransmitter release. The presence of both cardiomegaly and CHF in the two affected males and atrial fibrillation in one are consistent with abnormal RyR2 channel function. Since the dysfunction of RyR2 channels in the brain via 'leaky mutations' can result in mild developmental delay and seizures, our data also suggest a vital role for the CLIC2 protein in maintaining normal cognitive function via its interaction with RyRs in the brain. Therefore, our patients appear to suffer from a new channelopathy comprised of ID, seizures and cardiac problems because of enhanced Ca(2+) release through RyRs in neuronal cells and cardiac muscle cells.


Assuntos
Cardiomegalia/genética , Canalopatias/genética , Canais de Cloreto/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Mutação , Sequência de Aminoácidos , Cálcio/metabolismo , Cardiomegalia/complicações , Canalopatias/complicações , Canais de Cloreto/metabolismo , Família , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Humanos , Masculino , Dados de Sequência Molecular , Miócitos Cardíacos/metabolismo , Linhagem , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
15.
BMC Proc ; 3 Suppl 1: S6, 2009 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-19278545

RESUMO

BACKGROUND: We applied a range of genome-wide association (GWA) methods to map quantitative trait loci (QTL) in the simulated dataset provided by the 12th QTLMAS workshop in order to derive an effective strategy. RESULTS: A variance component linkage analysis revealed QTLs but with low resolution. Three single-marker based GWA methods were then applied: Transmission Disequilibrium Test and single marker regression, fitting an additive model or a genotype model, on phenotypes pre-corrected for pedigree and fixed effects. These methods detected QTL positions with high concordance to each other and with greater refinement of the linkage signals. Further multiple-marker and haplotype analyses confirmed the results with higher significance. Two-locus interaction analysis detected two epistatic pairs of markers that were not significant by marginal effects. Overall, using stringent Bonferroni thresholds we identified 9 additive QTL and 2 epistatic interactions, which together explained about 12.3% of the corrected phenotypic variance. CONCLUSION: The combination of methods that are robust against population stratification, like QTDT, with flexible linear models that take account of the family structure provided consistent results. Extensive simulations are still required to determine appropriate thresholds for more advanced model including epistasis.

16.
Genetics ; 180(3): 1691-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18791249

RESUMO

Combining global gene-expression profiling and genetic analysis of natural allelic variation (genetical genomics) has great potential in dissecting the genetic pathways underlying complex phenotypes. Efficient use of microarrays is paramount in experimental design as the cost of conducting this type of study is high. For those organisms where recombinant inbred lines are available for mapping, the "distant pair design" maximizes the number of informative contrasts over all marker loci. Here, we describe an extension of this design, named the "optimal pair design," for use with F2 crosses between outbred lines. The performance of this design is investigated by simulation and compared to several other two-color microarray designs. We show that, for a given number of microarrays, the optimal pair design outperforms all other designs considered for detection of expression quantitative trait loci (eQTL) with additive effects by linkage analysis. We also discuss the suitability of this design for outbred crosses in organisms with large genomes and for detection of dominance.


Assuntos
Corantes Fluorescentes , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Locos de Características Quantitativas , Projetos de Pesquisa , Animais , Mapeamento Cromossômico , Cor , Simulação por Computador , Cruzamentos Genéticos , Expressão Gênica
17.
Clin Rheumatol ; 27(12): 1497-505, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18654733

RESUMO

The objective of our study was to assess the efficacy of external qigong therapy (EQT), a traditional Chinese medicine practice, in reducing pain and improving functionality of patients with knee osteoarthritis (OA). One hundred twelve adults with knee OA were randomized to EQT or sham treatment (control); 106 completed treatment and were analyzed. Two therapists performed EQT individually, five to six sessions in 3 weeks. The sham healer mimicked EQT for the same number of sessions and duration. Patients and examining physician were blinded. Primary outcomes were Western Ontario MacMaster (WOMAC) pain and function; other outcomes included McGill Pain Questionnaire, time to walk 15 m, and range of motion squatting. Results of patients treated by the two healers were analyzed separately. Both treatment groups reported significant reduction in WOMAC scores after intervention. Patients treated by healer 2 reported greater reduction in pain (mean improvement -25.7 +/- 6.6 vs. -13.1 +/- 3.0; p < 0.01) and more improvement in functionality (-28.1 +/- 9.7 vs. -13.2 +/- 3.4; p < 0.01) than those in sham control and reduction in negative mood but not in anxiety or depression. Patients treated by healer 1 experienced improvement similar to control. The results of therapy persisted at 3 months follow-up for all groups. Mixed-effect models confirmed these findings with controlling for possible confounders. EQT might have a role in the treatment of OA, but our data indicate that all EQT healers are not equivalent. The apparent efficacy of EQT appears to be dependent on some quality of the healer. Further study on a larger scale with multiple EQT healers is necessary to determine the role (if any) of EQT in the treatment of OA and to identify differences in EQT techniques.


Assuntos
Exercícios Respiratórios , Osteoartrite do Joelho/terapia , Recuperação de Função Fisiológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Índice de Gravidade de Doença
18.
Genet Epidemiol ; 31 Suppl 1: S124-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18046761

RESUMO

Recent advances in molecular technologies have resulted in the ability to screen hundreds of thousands of single nucleotide polymorphisms and tens of thousands of gene expression profiles. While these data have the potential to inform investigations into disease etiologies and advance medicine, the question of how to adequately control both type I and type II error rates remains. Genetic Analysis Workshop 15 datasets provided a unique opportunity for participants to evaluate multiple testing strategies applicable to microarray and single nucleotide polymorphism data. The Genetic Analysis Workshop 15 multiple testing and false discovery rate group (Group 15) investigated three general categories for multiple testing corrections, which are summarized in this review: statistical independence, error rate adjustment, and data reduction. We show that while each approach may have certain advantages, adequate error control is largely dependent upon the question under consideration and often requires the use of multiple analytic strategies.


Assuntos
Testes Genéticos/métodos , Genoma Humano , Perfilação da Expressão Gênica , Humanos , Polimorfismo de Nucleotídeo Único
19.
Nat Genet ; 39(7): 857-64, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17554260

RESUMO

The Wellcome Trust Case Control Consortium (WTCCC) primary genome-wide association (GWA) scan on seven diseases, including the multifactorial autoimmune disease type 1 diabetes (T1D), shows associations at P < 5 x 10(-7) between T1D and six chromosome regions: 12q24, 12q13, 16p13, 18p11, 12p13 and 4q27. Here, we attempted to validate these and six other top findings in 4,000 individuals with T1D, 5,000 controls and 2,997 family trios independent of the WTCCC study. We confirmed unequivocally the associations of 12q24, 12q13, 16p13 and 18p11 (P(follow-up)

Assuntos
Mapeamento Cromossômico , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Genoma Humano , Adolescente , Estudos de Casos e Controles , Humanos , Polimorfismo de Nucleotídeo Único
20.
BMC Genet ; 8: 24, 2007 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-17509149

RESUMO

BACKGROUND: In an effort to locate susceptibility genes for type 1 diabetes (T1D) several genome-wide linkage scans have been undertaken. A chromosomal region designated IDDM10 retained genome-wide significance in a combined analysis of the main linkage scans. Here, we studied sequence polymorphisms in 23 Mb on chromosome 10p12-q11, including the putative IDDM10 region, to identify genes associated with T1D. RESULTS: Initially, we resequenced the functional candidate genes, CREM and SDF1, located in this region, genotyped 13 tag single nucleotide polymorphisms (SNPs) and found no association with T1D. We then undertook analysis of the whole 23 Mb region. We constructed and sequenced a contig tile path from two bacterial artificial clone libraries. By comparison with a clone library from an unrelated person used in the Human Genome Project, we identified 12,058 SNPs. We genotyped 303 SNPs and 25 polymorphic microsatellite markers in 765 multiplex T1D families and followed up 22 associated polymorphisms in up to 2,857 families. We found nominal evidence of association in six loci (P = 0.05 - 0.0026), located near the PAPD1 gene. Therefore, we resequenced 38.8 kb in this region, found 147 SNPs and genotyped 84 of them in the T1D families. We also tested 13 polymorphisms in the PAPD1 gene and in five other loci in 1,612 T1D patients and 1,828 controls from the UK. Overall, only the D10S193 microsatellite marker located 28 kb downstream of PAPD1 showed nominal evidence of association in both T1D families and in the case-control sample (P = 0.037 and 0.03, respectively). CONCLUSION: We conclude that polymorphisms in the CREM and SDF1 genes have no major effect on T1D. The weak T1D association that we detected in the association scan near the PAPD1 gene may be either false or due to a small genuine effect, and cannot explain linkage at the IDDM10 region.


Assuntos
Cromossomos Humanos Par 10 , Diabetes Mellitus Tipo 1/genética , Estudos de Casos e Controles , Primers do DNA , Feminino , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Masculino , Mapeamento Físico do Cromossomo , Polimorfismo de Nucleotídeo Único
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