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1.
Artigo em Inglês | MEDLINE | ID: mdl-38860847

RESUMO

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by vasoconstriction and remodeling of small pulmonary arteries (PAs). Central to the remodeling process is a switch of pulmonary vascular cells to a proliferative, apoptosis-resistant phenotype. Plasminogen activator inhibitor-1 (PAI-1) is the primary physiological inhibitor of urokinase-type and tissue-type plasminogen activators (uPA and tPA), but its role in PAH is unsettled. Here, we report that: (1) PAI-1 is deficient in remodeled small PAs and in early-passage PA smooth muscle and endothelial cells (PASMCs and PAECs) from subjects with PAH compared to controls; (2) PAI-1-/- mice spontaneously develop pulmonary vascular remodeling associated with up-regulation of mTORC1 signaling, pulmonary hypertension (PH), and right ventricle (RV) hypertrophy; and (3) pharmacological inhibition of uPA in human PAH PASMCs suppresses pro-proliferative mTORC1 and SMAD3 signaling, restores PAI-1 levels, reduces proliferation and induces apoptosis in vitro, and prevents the development of SU5416/hypoxia-induced PH and RV hypertrophy in vivo in mice. These data strongly suggest that down-regulation of PAI-1 in small PAs promotes vascular remodeling and PH due to unopposed activation of uPA and consequent up-regulation of mTOR and TGF-b signaling in PASMCs, and call for further studies to determine the potential benefits of targeting the PAI-1/uPA imbalance to attenuate and/or reverse pulmonary vascular remodeling and PH.

2.
bioRxiv ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37790328

RESUMO

Pulmonary arterial hypertension (PAH) is a progressive and potentially a rapidly fatal disease characterized by vasoconstriction and remodeling of small pulmonary arteries (PA) leading to increased pulmonary vascular resistance and right heart failure. Central to the remodeling process is a switch of the smooth muscle cells in small PAs (PASMC) to a proliferative, apoptosis-resistant phenotype. There is reason to suspect that the plasminogen activator system may play an important role in the remodeling program in PAH based on its roles in vascular post-injury restenosis, fibrosis, angiogenesis and tumorigenesis. Plasminogen activator inhibitor-1 (PAI-1) is the primary physiological inhibitor of the plasminogen activators - urokinase-type and tissue-type (uPA and tPA, respectively). Immunohisto- chemical and immunoblot analyses revealed that PAI-1 was deficient in smooth muscle areas of small remodeled PAs and early-passage PASMC from subjects with PAH compared to non-PAH controls. PAI1-/- male and female mice developed spontaneous pulmonary vascular remodeling and pulmonary hypertension (PH) as evidenced by significant increase in PA medial thickness, systolic right ventricular pressure, and right ventricular hypertrophy. Lastly, the uPA inhibitors upamostat (WX-671) and amiloride analog BB2-30F down-regulated mTORC1 and SMAD3, restored PAI-1 levels, reduced proliferation, and induced apoptosis in human PAH PASMC. We examined the effect of inhibition of uPA catalytic activity by BB2-30F on the development of SU5416/Hypoxia (SuHx)-induced PH in mice. Vehicletreated SuHx-exposed mice had up-regulated mTORC1 in small PAs, developed pulmonary vascular remodeling and PH, as evidenced by significant increase of PA MT, sRVP, RV hypertrophy, and a significant decrease in the pulmonary artery acceleration time/pulmonary ejection time (PAAT/PET) ratio compared to age- and sex-matched normoxia controls, whereas BB2-30F-treated group was protected from all these pathological changes. Taken together, our data strongly suggest that PAI-1 down- regulation in PASMC from human PAH lungs promotes PASMC hyper-proliferation, remodeling, and spontaneous PH due to unopposed uPA activation. Further studies are needed to determine the potential benefits of targeting the PAI-1/uPA imbalance to attenuate the progression and/or reverse pulmonary vascular remodeling and PH.

3.
Sci Rep ; 13(1): 6593, 2023 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-37087509

RESUMO

Pulmonary arterial hypertension (PAH) is a life-threatening condition characterized by a progressive increase in pulmonary vascular resistance leading to right ventricular failure and often death. Here we report that deficiency of transcription factor GATA6 is a shared pathological feature of PA endothelial (PAEC) and smooth muscle cells (PASMC) in human PAH and experimental PH, which is responsible for maintenance of hyper-proliferative cellular phenotypes, pulmonary vascular remodeling and pulmonary hypertension. We further show that GATA6 acts as a transcription factor and direct positive regulator of anti-oxidant enzymes, and its deficiency in PAH/PH pulmonary vascular cells induces oxidative stress and mitochondrial dysfunction. We demonstrate that GATA6 is regulated by the BMP10/BMP receptors axis and its loss in PAECs and PASMC in PAH supports BMPR deficiency. In addition, we have established that GATA6-deficient PAEC, acting in a paracrine manner, increase proliferation and induce other pathological changes in PASMC, supporting the importance of GATA6 in pulmonary vascular cell communication. Treatment with dimethyl fumarate resolved oxidative stress and BMPR deficiency, reversed hemodynamic changes caused by endothelial Gata6 loss in mice, and inhibited proliferation and induced apoptosis in human PAH PASMC, strongly suggesting that targeting GATA6 deficiency may provide a therapeutic advance for patients with PAH.


Assuntos
Proteínas Morfogenéticas Ósseas , Fator de Transcrição GATA6 , Estresse Oxidativo , Hipertensão Arterial Pulmonar , Animais , Camundongos , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Proliferação de Células , Células Cultivadas , Hipertensão Pulmonar Primária Familiar/patologia , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Miócitos de Músculo Liso/metabolismo , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Artéria Pulmonar/patologia , Remodelação Vascular
4.
Microorganisms ; 11(2)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838472

RESUMO

The ability of bacteriophage (phage), abundant within the gastrointestinal microbiome, to regulate bacterial populations within the same micro-environment offers prophylactic and therapeutic opportunities. Bacteria and phage have both been shown to interact intimately with mucin, and these interactions invariably effect the outcomes of phage predation within the intestine. To better understand the influence of the gastrointestinal micro-environment on phage predation, we employed enclosed, in vitro systems to investigate the roles of mucin concentration and agitation as a function of phage type and number on bacterial killing. Using two lytic coliphage, T4 and PhiX174, bacterial viability was quantified following exposure to phages at different multiplicities of infection (MOI) within increasing, physiological levels of mucin (0-4%) with and without agitation. Comparison of bacterial viability outcomes demonstrated that at low MOI, agitation in combination with higher mucin concentration (>2%) inhibited phage predation by both phages. However, when MOI was increased, PhiX predation was recovered regardless of mucin concentration or agitation. In contrast, only constant agitation of samples containing a high MOI of T4 demonstrated phage predation; briefly agitated samples remained hindered. Our results demonstrate that each phage-bacteria pairing is uniquely influenced by environmental factors, and these should be considered when determining the potential efficacy of phage predation under homeostatic or therapeutic circumstances.

5.
Front Med (Lausanne) ; 9: 886868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35836951

RESUMO

Hyper-proliferation of pulmonary arterial vascular smooth muscle cells (PAVSMC) is an important pathological component of pulmonary vascular remodeling in pulmonary arterial hypertension (PAH). Lipogenesis is linked to numerous proliferative diseases, but its role in PAVSMC proliferation in PAH remains to be elucidated. We found that early-passage human PAH PAVSMC had significant up-regulation of key fatty acids synthesis enzymes ATP-citrate lyase (ACLY), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FASN), and increased unstimulated proliferation compared to control human PAVSMC. Treatment with an allosteric ACC inhibitor 5-tetradecyloxy-2-furoic acid (TOFA) significantly decreased proliferation and induced apoptosis of human PAH PAVSMC. Intracellular lipid content and proliferation of PAH PAVSMC were not reduced by incubation in lipid-depleted media but suppressed by a non-metabolizable analog of glucose 2-Deoxy-D-glucose (2-DG) and partially restored by addition of pyruvate. Protein kinase Akt was upregulated in human PAH PAVSMC in a sirtuin 7 (SIRT7)- and c-Jun N-terminal kinase (JNK)-dependent manner. Pharmacological inhibition of Akt down-regulated ACLY and ACC, significantly reduced intracellular lipid content, inhibited proliferation and induced apoptosis of human PAH PAVSMC. Taken together, these data demonstrate that human PAH PAVSMC have up-regulated lipogenesis, which is supported in an Akt- and glycolysis-dependent manner and is required for increased proliferation and survival. Our data suggest that there is a mechanistic link between glycolysis, lipogenesis, and the proliferation of human PAH PAVSMC and call for further studies to determine the potential attractiveness of a SIRT7/JNK-Akt-lipogenesis axis as a target pathway to inhibit PAVSMC hyper-proliferation in PAH.

6.
Circ Res ; 130(5): 760-778, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35124974

RESUMO

RATIONALE: The MSTs (mammalian Ste20-like kinases) 1/2 are members of the HIPPO pathway that act as growth suppressors in adult proliferative diseases. Pulmonary arterial hypertension (PAH) manifests by increased proliferation and survival of pulmonary vascular cells in small PAs, pulmonary vascular remodeling, and the rise of pulmonary arterial pressure. The role of MST1/2 in PAH is currently unknown. OBJECTIVE: To investigate the roles and mechanisms of the action of MST1 and MST2 in PAH. METHODS AND RESULTS: Using early-passage pulmonary vascular cells from PAH and nondiseased lungs and mice with smooth muscle-specific tamoxifen-inducible Mst1/2 knockdown, we found that, in contrast to canonical antiproliferative/proapoptotic roles, MST1/2 act as proproliferative/prosurvival molecules in human PAH pulmonary arterial vascular smooth muscle cells and pulmonary arterial adventitial fibroblasts and support established pulmonary vascular remodeling and pulmonary hypertension in mice with SU5416/hypoxia-induced pulmonary hypertension. By using unbiased proteomic analysis, gain- and loss-of function approaches, and pharmacological inhibition of MST1/2 kinase activity by XMU-MP-1, we next evaluated mechanisms of regulation and function of MST1/2 in PAH pulmonary vascular cells. We found that, in PAH pulmonary arterial adventitial fibroblasts, the proproliferative function of MST1/2 is caused by IL-6-dependent MST1/2 overexpression, which induces PSMC6-dependent downregulation of forkhead homeobox type O 3 and hyperproliferation. In PAH pulmonary arterial vascular smooth muscle cells, MST1/2 acted via forming a disease-specific interaction with BUB3 and supported ECM (extracellular matrix)- and USP10-dependent BUB3 accumulation, upregulation of Akt-mTORC1, cell proliferation, and survival. Supporting our in vitro observations, smooth muscle-specific Mst1/2 knockdown halted upregulation of Akt-mTORC1 in small muscular PAs of mice with SU5416/hypoxia-induced pulmonary hypertension. CONCLUSIONS: Together, this study describes a novel proproliferative/prosurvival role of MST1/2 in PAH pulmonary vasculature, provides a novel mechanistic link from MST1/2 via BUB3 and forkhead homeobox type O to the abnormal proliferation and survival of pulmonary arterial vascular smooth muscle cells and pulmonary arterial adventitial fibroblasts, remodeling and pulmonary hypertension, and suggests new target pathways for therapeutic intervention.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Hipertensão Pulmonar , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Hipertensão Arterial Pulmonar , Animais , Proliferação de Células , Células Cultivadas , Hipertensão Pulmonar/metabolismo , Hipóxia/metabolismo , Mamíferos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Miócitos de Músculo Liso/metabolismo , Proteômica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Hipertensão Arterial Pulmonar/genética , Artéria Pulmonar/metabolismo , Remodelação Vascular/fisiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-31750259

RESUMO

Fecal microbiota transplantation (FMT) is an effective tool for treating Clostridium difficile infection in the setting of dysbiosis of the intestinal microbiome. FMT for other forms of human disorders linked to dysbiosis have been less effective. The fecal microbiota contains a high density of virus-like particles (VLP), up to 90% of which are bacteriophages, thought to have a role in regulating gut bacterial populations. We hypothesized that transplantation of the phage-containing fecal VLP fraction may reduce bacterial density in the dysbiotic setting of small intestinal bacterial overgrowth (SIBO). In an experiment using fecal transplantation, we compared the effect of the fecal VLP fraction (bacteria removed) against "Whole" FMT (bacteria intact) on the ileal microbiome. Recipients were either treated with a 30-day high-fat diet (HFD) as a model of dysbiosis to induce SIBO or were on a standard diet (SD). We observed that transplantation of fecal VLPs from donors on a HFD was sufficient to alter the ileal microbiota, but the effect was dependent on diet of the recipient. In recipients on a HFD, ileal bacterial density was reduced. In recipients on a SD, the ileal microbiome transitioned toward the composition associated with a HFD. In both recipient groups, transplantation of fecal VLP fraction alone produced the same outcome as whole FMT. Neither treatment altered expression of antimicrobial peptides. These findings demonstrated a potential role of VLPs, likely phages, for modifying the gut microbiome during dysbiosis.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Disbiose/terapia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Intestino Delgado/microbiologia , Animais , Carga Bacteriana , Bacteriófagos/isolamento & purificação , Bacteriófagos/ultraestrutura , Clostridioides difficile , Modelos Animais de Doenças , Enterocolite Pseudomembranosa/microbiologia , Enterocolite Pseudomembranosa/terapia , Transplante de Microbiota Fecal/métodos , Metagenômica/métodos , Camundongos , RNA Ribossômico 16S , Resultado do Tratamento
9.
F1000Res ; 82019.
Artigo em Inglês | MEDLINE | ID: mdl-31316751

RESUMO

Bacteriophages are the most prominent members of the gut microbiome, outnumbering their bacterial hosts by a factor of 10. Phages are bacteria-specific viruses that are gaining attention as highly influential regulators of the gut bacterial community. Dysregulation of the gut bacterial community contributes to dysbiosis, a microbiome disorder characterized by compositional and functional changes that contribute to disease. A role for phages in gut microbiome dysbiosis is emerging with evidence that the gut phage community is altered in dysbiosis-associated disorders such as colorectal cancer and inflammatory bowel disease. Several recent studies have linked successful fecal microbiota transplantation to uptake of the donor's gut phage community, offering some insight into why some recipients respond to treatment whereas others do not. Here, we review the literature supporting a role for phages in mediating the gut bacterial community, giving special attention to Western diet dysbiosis as a case study to demonstrate a theoretical phage-based mechanism for the establishment and maintenance of dysbiosis.


Assuntos
Bacteriófagos , Disbiose , Microbioma Gastrointestinal , Microbiota , Humanos , Modelos Teóricos
10.
Nat Commun ; 10(1): 1710, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30979884

RESUMO

Whether fragile X mental retardation protein (FMRP) target mRNAs and neuronal activity contributing to elevated basal neuronal protein synthesis in fragile X syndrome (FXS) is unclear. Our proteomic experiments reveal that the de novo translational profile in FXS model mice is altered at steady state and in response to metabotropic glutamate receptor (mGluR) stimulation, but the proteins expressed differ under these conditions. Several altered proteins, including Hexokinase 1 and Ras, also are expressed in the blood of FXS model mice and pharmacological treatments previously reported to ameliorate phenotypes modify their abundance in blood. In addition, plasma levels of Hexokinase 1 and Ras differ between FXS patients and healthy volunteers. Our data suggest that brain-based de novo proteomics in FXS model mice can be used to find altered expression of proteins in blood that could serve as disease-state biomarkers in individuals with FXS.


Assuntos
Síndrome do Cromossomo X Frágil/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Adolescente , Adulto , Animais , Biomarcadores/sangue , Modelos Animais de Doenças , Feminino , Síndrome do Cromossomo X Frágil/genética , Hexoquinase/sangue , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Adulto Jovem , Proteínas ras/metabolismo
11.
World J Gastrointest Pharmacol Ther ; 8(3): 162-173, 2017 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-28828194

RESUMO

The practice of phage therapy, which uses bacterial viruses (phages) to treat bacterial infections, has been around for almost a century. The universal decline in the effectiveness of antibiotics has generated renewed interest in revisiting this practice. Conventionally, phage therapy relies on the use of naturally-occurring phages to infect and lyse bacteria at the site of infection. Biotechnological advances have further expanded the repertoire of potential phage therapeutics to include novel strategies using bioengineered phages and purified phage lytic proteins. Current research on the use of phages and their lytic proteins, specifically against multidrug-resistant bacterial infections, suggests phage therapy has the potential to be used as either an alternative or a supplement to antibiotic treatments. Antibacterial therapies, whether phage- or antibiotic-based, each have relative advantages and disadvantages; accordingly, many considerations must be taken into account when designing novel therapeutic approaches for preventing and treating bacterial infections. Although much is still unknown about the interactions between phage, bacteria, and human host, the time to take phage therapy seriously seems to be rapidly approaching.

12.
Medicine (Baltimore) ; 95(31): e4433, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27495067

RESUMO

For chronic hepatitis B (CHB), alanine aminotransferase (ALT) ≥2 × upper limit of normal (ULN) is often used as a major criteria to initiate treatment in absence of cirrhosis, though patients with lower ALT may not be free from future risk of hepatocellular carcinoma (HCC). We aimed to examine the effect of antiviral therapy on HCC incidence based on ALT levels.We performed a retrospective study on 3665 patients consisting of United States and Taiwanese REVEAL-HBV cohort who were consecutive, treatment-naïve, noncirrhotic CHB patients aged ≥40 years. Patients were categorized by ALT cutoffs (≥2 × ULN vs <2 × ULN) and subgrouped by treatment status. Kaplan-Meier and Cox proportional hazards models were used to calculate cumulative incidence and hazard ratio (HR) of HCC adjusting for REACH-B scores.A total of 202 patients developed HCC. Antiviral treatment significantly reduced HCC risk: HR 0.24, 95% confidence interval 0.10-0.58; P = 0.001. HCC incidence per 100,000 person-years was significantly higher in untreated versus treated patients, even for those with ALT < 2 × ULN: 314.46 versus 0 per 100,000 person-years, P = 0.0042. For patients with Hepatitis B Virus (HBV) Deoxyribonucleic Acid (DNA) ≥ 2000 IU/mL, the number-needed-to-treat (NNT) were 15 and 14 to prevent 1 incident HCC at year 10 for patients with ALT < 2 × ULN and ≥2 × ULN, respectively.After adjustment by REACH-B score, antiviral treatment significantly decreased HCC incidence even in patients with ALT < 2 × ULN. NNT to prevent 1 incident HCC after 10 years of therapy was low (14-15) in patients with mildly elevated HBV DNA ≥ 2000 IU/mL regardless of ALT levels.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/prevenção & controle , Transaminases/sangue , Adulto , Distribuição por Idade , Estudos de Coortes , Feminino , Humanos , Incidência , Cirrose Hepática/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Distribuição por Sexo
13.
World Neurosurg ; 91: 149-53, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27020975

RESUMO

OBJECTIVE: A large-scale study on postoperative complications of lumbar fusion surgery for spondylolisthesis comparing patients >80 years old with younger patients has not been performed. The purpose of this study is to assess the effects of extreme age (>80 years old) on early postoperative outcomes after single-level lumbar fusions for spondylolisthesis. METHODS: From a validated multicenter surgical database, 2475 patients who underwent a single-level lumbar fusion procedure for spondylolisthesis were selected retrospectively. An extreme age cohort with 227 patients >80 years old was compared with a typical age cohort with 2248 patients 45-65 years old. RESULTS: The preoperative characteristics and comorbidities were different between the typical age cohort and the extreme age cohort, with older patients having more preoperative comorbidities, including a lack of independent functional health status before surgery (P < 0.001), severe chronic obstructive pulmonary disease (P <0.020), and hypertension requiring medication (P < 0.001). There was significantly greater morbidity among the >80 cohort regarding urinary tract infection (P = 0.008; odds ratio = 3.30; 95% confidence interval, 1.47-7.40) and intraoperative and postoperative transfusions (P < 0.001; odds ratio = 2.186; 95% confidence interval, 1.54-3.11). There was significantly greater morbidity among the younger cohort regarding cardiac arrest requiring cardiopulmonary resuscitation (P = 0.043; odds ratio = 0.099; 95% confidence interval, 0.014-0.704). CONCLUSIONS: This is the first large study comparing the rates of postoperative complications of lumbar fusion surgery for spondylolisthesis in patients >80 years old versus younger patients. The data support that age alone should not exclude a patient for this procedure. However, extra caution is warranted given the slightly increased morbidity.


Assuntos
Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/epidemiologia , Fusão Vertebral/estatística & dados numéricos , Espondilolistese/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos
14.
World J Clin Cases ; 4(3): 71-5, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26989671

RESUMO

Approximately 240 million people are chronically infected with hepatitis B. The implementation of rigorous vaccination programs has led to an overall decrease in the prevalence of this disease worldwide but this may also have led to emergence of viral mutations that can escape the protection of hepatitis B surface antibody. As this phenomenon is increasingly recognized, concern for transmission to vaccinated individuals has also been raised. Herein, we describe two cases where the suspected presence of a hepatitis B surface antigen escape mutation impacted the decision to initiate early antiviral therapy, as well as provide a brief review of these mutations. Our findings described here suggest that a lower threshold for initiating therapy in these individuals should be considered in order to reduce the risk of transmission, as vaccination does not provide protection.

15.
BMJ Open Gastroenterol ; 2(1): e000049, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26462288

RESUMO

BACKGROUND: Pegylated interferon and ribavirin (PEG-IFN+RBV) may be more cost-effective than direct-acting antivirals in resource-limited settings. Current literature suggests sustained virological response (SVR) in hepatitis C virus genotype 4 (HCV-4) is similar to genotype 1 (HCV-1), but worse than 2 and 3 (HCV-2/3). However, few studies have compared treatment response between these groups and these have been limited by small sample sizes with heterogeneous designs. We performed a meta-analysis of SVR predictors in HCV-4 versus HCV-1, 2, and 3 patients treated with PEG-IFN+RBV. METHODS: In November 2013, we searched for 'genotype 4' in MEDLINE/EMBASE databases and scientific conferences. We included original articles with ≥25 treatment-naïve HCV-4 and comparisons to HCV-1, 2, and/or 3 patients treated with PEG-IFN+RBV. Random effects modelling was used with heterogeneity defined by Cochrane Q-test (p value<0.10) and I(2) statistic (>50%). RESULTS: Five studies with 20 014 patients (899 HCV-4; 12 033 HCV-1; and 7082 HCV-2/3 patients) were included. SVR was 53% (CI 43% to 62%) for HCV-4, 44% (CI 40% to 47%) for HCV-1; and 73% (CI 58% to 84%) for HCV-2/3. SVR with EVR (early virological response) was 75% (CI 61% to 86%) in HCV-4; 64% (CI 46% to 79%) in HCV-1; and 85% (CI 71% to 93%) in HCV-2/3. SVR without EVR was 10% (CI 6% to 17%) for HCV-4; 13% (CI 12% to 15%) for HCV-1; and 23% (CI 16% to 33%) for HCV-2/3. CONCLUSIONS: SVR rates are similar in HCV-4 (∼50%) and HCV-1 (∼40%). Lack of EVR is a good stopping rule for HCV-4 and HCV-1 since only 10% subsequently achieve SVR. In HCV-4 patients with EVR, three-quarters can expect to achieve SVR with PEG-IFN+RBV.

16.
J Clin Neurosci ; 22(12): 1867-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26375325

RESUMO

We aimed to identify the role of age in intracerebral hemorrhage (ICH), as well as characterize the most commonly used age cut off points in the literature, with the hope of understanding and guiding treatment. Strokes are one of the leading causes of death in the USA, and ICH is the deadliest type. Age is a strong risk factor, but it also affects the body in numerous ways, including changes to the cardiovascular and central nervous systems that interplay with the multiple risk factors for ICH. Understanding the role of age in risk and outcomes of ICH can guide treatment and future clinical trials. A current review of the literature suggests that the age cut offs for increased rates of mortality and morbidity vary from 60-80 years of age, with the most common age cut offs being at 65 or 70 years of age. In addition to age as a determinant of ICH outcomes, age has its own effects on the maturing body in terms of changes in physiology, while also increasing the risk of multiple chronic health conditions and comorbidities, including hypertension, diabetes, and anticoagulant treatment for atrial fibrillation, all of which contribute to the pathology of ICH. The interaction of these chronic conditions, changes in physiology, age, and ICH is evident. However, the exact mechanism and extent of the impacts remains unclear. The ambiguity of these connections may be further obscured by individual patient preferences, and there are limitations in the literature which guides the current recommendations for aging patients.


Assuntos
Hemorragia Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Humanos , Fatores de Risco
17.
Evol Appl ; 8(1): 9-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25667600

RESUMO

Understanding the transition of bacterial species from commensal to pathogen, or vice versa, is a key application of evolutionary theory to preventative medicine. This requires working knowledge of the molecular interaction between hosts and bacteria, ecological interactions among microbes, spatial variation in bacterial prevalence or host life history, and evolution in response to these factors. However, there are very few systems for which such broad datasets are available. One exception is the gram-negative bacterium, Helicobacter pylori, which infects upwards of 50% of the global human population. This bacterium is associated with a wide breadth of human gastrointestinal disease, including numerous cancers, inflammatory disorders, and pathogenic infections, but is also known to confer fitness benefits to its host both indirectly, through interactions with other pathogens, and directly. Outstanding questions are therefore why, when, and how this bacterium transitions along the parasitism-mutualism continuum. We examine known virulence factors, genetic predispositions of the host, and environmental contributors that impact progression of clinical disease and help define geographical trends in disease incidence. We also highlight the complexity of the interaction and discuss future therapeutic strategies for disease management and public health in light of the longstanding evolutionary history between the bacterium and its human host.

18.
Clin Gastroenterol Hepatol ; 12(2): 327-333.e1, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23978349

RESUMO

BACKGROUND & AIMS: Interleukin (IL)-28B (interferon-λ 3) genotype is the strongest predictor of response of patients with hepatitis C virus (HCV) infection to antiviral therapy. However, patients with HCV infection often have physical or mental comorbidities that contraindicate or complicate treatment, regardless of their genotype. The potential role of IL28B genotype within the context of patients' clinical and social environment is therefore unclear. METHODS: We characterized the IL28B genotype (for rs12980275 and rs8099917) in 308 patients (mean age, 56 y; 25% African American; 38% with advanced-stage fibrosis) with genotype 1 HCV infection seen at the Michael E. DeBakey Veterans Administration Medical Center in Houston, Texas, from May 1, 2009, through April 1, 2012. We evaluated their eligibility for antiviral treatment based on clinical and social factors such as physical or mental health comorbidity, ongoing alcohol or drug use, and noncompliance with treatment evaluation. RESULTS: Of the 308 subjects, 40% were homozygous for rs12980275 (associated with response to therapy), 46% were heterozygous, and 15% were homozygous for alleles associated with reduced response to therapy. Overall, 36% of patients were considered to be ineligible for treatment; of these, 40% had the rs12980275 genotype. More than half of the patients with rs12980275 who were ineligible for treatment were excluded because of mental health comorbidities; one-third of these patients had advanced fibrosis. The reason(s) for treatment exclusion resolved in only 8% of patients during a mean 1.5 years of follow-up evaluation. CONCLUSIONS: In a well-characterized cohort of patients with HCV, a large proportion (40%) with IL28B polymorphisms associated with response to therapy is ineligible for treatment because of contraindications. One potential role of IL28B genotype analysis could be to identify patients who, although not currently eligible for antiviral treatment, could become so by modifying fixable exclusions to treatment.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interleucinas/genética , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Negro ou Afro-Americano/genética , Antivirais/uso terapêutico , Comorbidade , Contraindicações , Tratamento Farmacológico , Frequência do Gene , Genótipo , Hepatite C Crônica/epidemiologia , Humanos , Interferons , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Polimorfismo de Nucleotídeo Único , População Branca/genética
19.
Clin Lymphoma Myeloma Leuk ; 14(2): 102-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24373789

RESUMO

BACKGROUND: The prognosis of multiple myeloma (MM) has improved in recent years. Therefore, second malignant neoplasms (SMNs) may become an issue for longer term survivors with MM. An increased incidence of second malignancies was reported in patients who received lenalidomide for relapsed or refractory myeloma. PATIENTS AND METHODS: Data from the Tumor Registry of the Michael E. DeBakey VA Medical Center (1995-2010) were analyzed. Kaplan-Meier survival statistics were calculated. RESULTS: In 197 patients with MM, 39 different cancers were observed in 33 patients, the large majority occurring before the diagnosis of MM, with most being early-stage or good-prognosis malignancies. Despite this, the prognosis of patients with a second or third cancer was clearly inferior to patients without other cancers. Notable was a significant number of prostate cancers as preexisting malignancies. CONCLUSION: At present, most other cancers (for which MM is the secondary malignancy) may not be related to the treatment for myeloma, but due to underlying immunologic, genetic, or environmental factors. Larger studies and careful follow-up, especially in good-risk patients treated with novel agents, are indicated.


Assuntos
Mieloma Múltiplo/tratamento farmacológico , Segunda Neoplasia Primária/diagnóstico , Sistema de Registros/estatística & dados numéricos , Talidomida/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Lenalidomida , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Projetos Piloto , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Sobreviventes/estatística & dados numéricos , Texas , Talidomida/uso terapêutico , Estados Unidos/epidemiologia , United States Department of Veterans Affairs
20.
Am J Gastroenterol ; 108(10): 1576-83, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23857477

RESUMO

OBJECTIVES: This study examined Barrett's esophagus (BE) risk factors in veterans to determine the association between risk of BE and use of oral bisphosphonates. METHODS: We conducted a case-control study among eligible patients scheduled for an elective esophagogastroduodenoscopy (EGD) and a sample of patients eligible for screening colonoscopy recruited from primary care clinics from a single VA Medical Center. Cases with definitive BE were compared with controls; all underwent study EGD. Use of oral bisphosphonates was ascertained by reviewing filled prescriptions in electronic pharmacy records. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs), using multivariate logistic regression modeling while adjusting for sex, age, race, proton-pump inhibitor use, hiatal hernia, waist-to-hip ratio, Helicobacter pylori infection, and gastroesophageal reflux disorder (GERD) symptoms. RESULTS: There were 285 BE cases, 1,122 endoscopy controls, and 496 primary care controls. Alendronate and risedronate were the only oral bisphosphonates prescribed. The proportion of BE cases with filled prescription of oral bisphosphonates (4.6%) was greater than in endoscopy controls (1.6%) or primary care controls (2.9%). In the adjusted analysis, oral bisphosphonate use was significantly associated with BE risk (OR=2.33; 95% CI: 1.11-4.88) compared with the combined control groups. This association remained significant when BE cases were compared with endoscopy controls only (OR=2.74; 95% CI: 1.28-5.87) but was attenuated when compared with primary care controls only (OR=2.60; 95% CI: 0.99-6.84). The association was observed in patients with GERD symptoms (OR=3.29; 95% CI: 1.36-7.97) but not in those without GERD symptoms. CONCLUSION: Oral bisphosphonate use may increase the risk for BE, especially among patients with GERD.


Assuntos
Esôfago de Barrett/epidemiologia , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Osteoporose/tratamento farmacológico , Idoso , Alendronato/uso terapêutico , Estudos de Casos e Controles , Endoscopia do Sistema Digestório , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/uso terapêutico , Feminino , Refluxo Gastroesofágico/epidemiologia , Infecções por Helicobacter/epidemiologia , Hérnia Hiatal/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Inibidores da Bomba de Prótons/uso terapêutico , Ácido Risedrônico , Fatores de Risco , Estados Unidos/epidemiologia , Veteranos , Relação Cintura-Quadril
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