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1.
Front Immunol ; 15: 1371706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650935

RESUMO

Pulmonary hypertension (PH) pathogenesis is driven by inflammatory and metabolic derangements as well as glycolytic reprogramming. Induction of both interleukin 6 (IL6) and transglutaminase 2 (TG2) expression participates in human and experimental cardiovascular diseases. However, little is known about the role of TG2 in these pathologic processes. The current study aimed to investigate the molecular interactions between TG2 and IL6 in mediation of tissue remodeling in PH. A lung-specific IL6 over-expressing transgenic mouse strain showed elevated right ventricular (RV) systolic pressure as well as increased wet and dry tissue weights and tissue fibrosis in both lungs and RVs compared to age-matched wild-type littermates. In addition, IL6 over-expression induced the glycolytic and fibrogenic markers, hypoxia-inducible factor 1α, pyruvate kinase M2 (PKM2), and TG2. Consistent with these findings, IL6 induced the expression of both glycolytic and pro-fibrogenic markers in cultured lung fibroblasts. IL6 also induced TG2 activation and the accumulation of TG2 in the extracellular matrix. Pharmacologic inhibition of the glycolytic enzyme, PKM2 significantly attenuated IL6-induced TG2 activity and fibrogenesis. Thus, we conclude that IL6-induced TG2 activity and cardiopulmonary remodeling associated with tissue fibrosis are under regulatory control of the glycolytic enzyme, PKM2.


Assuntos
Fibroblastos , Proteínas de Ligação ao GTP , Hipertensão Pulmonar , Interleucina-6 , Pulmão , Camundongos Transgênicos , Proteína 2 Glutamina gama-Glutamiltransferase , Piruvato Quinase , Transglutaminases , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibrose , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/etiologia , Interleucina-6/metabolismo , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Piruvato Quinase/metabolismo , Piruvato Quinase/genética , Transglutaminases/metabolismo , Transglutaminases/genética
2.
Eur Heart J ; 44(22): 1979-1991, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-36879444

RESUMO

AIMS: Iron deficiency is common in pulmonary hypertension, but its clinical significance and optimal definition remain unclear. METHODS AND RESULTS: Phenotypic data for 1028 patients enrolled in the Redefining Pulmonary Hypertension through Pulmonary Vascular Disease Phenomics study were analyzed. Iron deficiency was defined using the conventional heart failure definition and also based upon optimal cut-points associated with impaired peak oxygen consumption (peakVO2), 6-min walk test distance, and 36-Item Short Form Survey (SF-36) scores. The relationships between iron deficiency and cardiac and pulmonary vascular function and structure and outcomes were assessed. The heart failure definition of iron deficiency endorsed by pulmonary hypertension guidelines did not identify patients with reduced peakVO2, 6-min walk test, and SF-36 (P > 0.208 for all), but defining iron deficiency as transferrin saturation (TSAT) <21% did. Compared to those with TSAT ≥21%, patients with TSAT <21% demonstrated lower peakVO2 [absolute difference: -1.89 (-2.73 to -1.04) mL/kg/min], 6-min walk test distance [absolute difference: -34 (-51 to -17) m], and SF-36 physical component score [absolute difference: -2.5 (-1.3 to -3.8)] after adjusting for age, sex, and hemoglobin (all P < 0.001). Patients with a TSAT <21% had more right ventricular remodeling on cardiac magnetic resonance but similar pulmonary vascular resistance on catheterization. Transferrin saturation <21% was also associated with increased mortality risk (hazard ratio 1.63, 95% confidence interval 1.13-2.34; P = 0.009) after adjusting for sex, age, hemoglobin, and N-terminal pro-B-type natriuretic peptide. CONCLUSION: The definition of iron deficiency in the 2022 European Society of Cardiology (ESC)/European Respiratory Society (ERS) pulmonary hypertension guidelines does not identify patients with lower exercise capacity or functional status, while a definition of TSAT <21% identifies patients with lower exercise capacity, worse functional status, right heart remodeling, and adverse clinical outcomes.


Assuntos
Anemia Ferropriva , Insuficiência Cardíaca , Hipertensão Pulmonar , Deficiências de Ferro , Humanos , Anemia Ferropriva/complicações , Hemoglobinas , Transferrinas
3.
J Bronchology Interv Pulmonol ; 29(4): 283-289, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35275851

RESUMO

BACKGROUND: During diagnostic bronchoscopies, conscious sedation improves patient tolerance, but it can contribute to hypercapnia and hypoxia by various mechanisms including depression of ventilatory drive. This prospective study was undertaken to determine the frequency of respiratory events and associated oxygen desaturations during bronchoscopy with conscious sedation. PATIENTS AND METHODS: The Nox-T3 monitoring system was placed before starting the bronchoscopy and remained in place for 30 minutes following the procedure. The primary endpoint was the occurrence of obstructive and central apneic events during bronchoscopy under conscious sedation. RESULTS: Obstructive events (apnea and hypopnea) occurred in 100% of patients (n=31), and central apneas occurred in 58% of patients (n=18) during the procedure with a median of 9 and 2 events per patient, respectively. During recovery, a significant proportion of patients had detectable obstructive (86%) and central (36%) events. Higher body mass index was associated with oxygen desaturation to <90% and with the need for escalation of care. Furthermore, a conscious sedation regimen that included propofol was significantly associated with central apneic events. CONCLUSION: Respiratory events are common during and immediately postprocedure after conscious sedation for bronchoscopy. Most events are obstructive, and the use of propofol predisposes to central apneas during the procedure. Both types of events are associated with a higher body mass index. Oxygen desaturation to <90% triggers escalation of care. A further prospective study will be required to determine the clinical significance of these apneic events and whether alleviating these events will improve the safety and outcomes of bronchoscopic procedures performed under conscious sedation.


Assuntos
Propofol , Apneia do Sono Tipo Central , Broncoscopia/efeitos adversos , Broncoscopia/métodos , Sedação Consciente/efeitos adversos , Sedação Consciente/métodos , Humanos , Incidência , Oxigênio , Propofol/efeitos adversos , Estudos Prospectivos , Apneia do Sono Tipo Central/induzido quimicamente
4.
J Am Chem Soc ; 143(5): 2331-2339, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33427467

RESUMO

The low-lying electronic states of Irgacure 2959, a Norrish-type I photoinitiator, complexed with a single metal cation are investigated in the gas phase by photodissociation action spectroscopy. Analysis of the band shifts using quantum chemical calculations (TD-DFT and SCS-CC2) reveals the underlying influence of the charge on the key electronic energy levels. Since the cations (H+, Li+, Na+, K+, Zn2+, Ca2+, and Mg2+) bind at varying distances, the magnitude of the electric field at the center of the chromophore due to the cation is altered, and this shifts the electronic states by different amounts. Photodissociation action spectra of cation-Irg complexes show that absorption transitions to the first 1ππ* state are red-shifted with a magnitude proportional to the electric field strength (with red shifts >1 eV), and in most cases, the cation is essentially acting as a point charge. Calculations show that a neighboring 3nπ* state, a key state for the α-cleavage pathway, is destabilized (blue-shifted) by the orientated electric field. As such, if the 1ππ*-3nπ* energy gap is reduced, increased intersystem crossing rates are expected, resulting in higher yields of the desired radical photoproducts, and this is controlled by the orientated electric field arising from the cation.

5.
PLoS One ; 14(8): e0221728, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31437238

RESUMO

Vascular smooth muscle cells from the pulmonary arteries (HPASMC) of subjects with pulmonary arterial hypertension (PAH) exhibit hyperplastic growth. The PAH HPASMC display an increased sensitivity to fetal bovine serum (FBS) and undergo growth at a very low, 0.2%, FBS concentration. On the other hand, normal HPASMC (obtained from non-PAH donors) do not proliferate at low FBS (0.2%). A previous genomic study suggested that the nuclear factor, FOXM1 and the polo like kinase 1 (PLK1) are involved in promoting this hyperplastic growth of the PAH HPASMC. Here we find that limiting the action of FOXM1 or PLK1 not only restricts the hyperplastic proliferation of the PAH HPASMC but also modulates the FBS stimulated growth of normal HPASMC. The PAH HPASMC exhibit significantly elevated PLK1 and FOXM1 expression and decreased p27 (quiescence protein) levels compared to normal HPASMC. Regulation of the expression of FOXM1 and PLK1 is accompanied by the regulation of downstream expression of cell cycle components, Aurora B, cyclin B1 and cyclin D1. Expression of these cell cycle components is reversed by the knockdown of FOXM1 or PLK1 expression/activity. Furthermore, the knockdown of PLK1 expression lowers the protein level of FOXM1. On the other hand, inhibiting the action of FOXO1, a growth inhibitor, further increases the expression of FOXM1 in PAH HPASMC. Although PLK1 and FOXM1 clearly participate in PAH HPASMC hyperplasia, at this time it is not clear whether their increased activity is the primary driver of the hyperplastic behavior of the PAH HPASMC or merely a component of the pathway(s) leading to this response.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteína Forkhead Box M1/metabolismo , Miócitos de Músculo Liso/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Hipertensão Arterial Pulmonar/patologia , Artéria Pulmonar/patologia , Ciclo Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , DNA/biossíntese , Proteína Forkhead Box M1/antagonistas & inibidores , Humanos , Hiperplasia , Modelos Biológicos , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Quinase 1 Polo-Like
6.
Respir Care ; 64(6): 647-657, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31110034

RESUMO

Noninvasive ventilation is well established as the ventilatory modality of first choice to treat acute or acute-on-chronic hypercapnic respiratory failure in patients with COPD by improving dyspnea and gas exchange, avoiding the need for intubation, and reducing morbidity and mortality rates. Noninvasive ventilation also offers benefit for patients with COPD and with accompanying pneumonia or with hypercapnic respiratory failure in postextubation, postoperative, and do not intubate settings. Noninvasive ventilation, in addition, offers benefit in other forms of acute hypercapnic respiratory failure, including those caused by asthma, cystic fibrosis, and obesity hypoventilation. A newer form of noninvasive ventilatory assistance, high-flow nasal cannula, has emerged in recent years as a technique to not only oxygenate effectively but also to improve ventilatory efficiency and reduce the work of breathing in patients with severe COPD. Results of recent studies indicate that high-flow nasal cannula therapy can benefit some patients with acute hypercapnic respiratory failure, either instead of or in combination with noninvasive ventilation, but more study is needed.


Assuntos
Hipercapnia/terapia , Ventilação não Invasiva/métodos , Doença Pulmonar Obstrutiva Crônica/terapia , Insuficiência Respiratória/terapia , Humanos , Hipercapnia/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Insuficiência Respiratória/fisiopatologia , Trabalho Respiratório
9.
Eur Respir J ; 51(6)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29954925

RESUMO

High oestradiol (E2) and low dehydroepiandrosterone-sulfate (DHEA-S) levels are risk factors for pulmonary arterial hypertension (PAH) in men, but whether sex hormones are related to PAH in women is unknown.Post-menopausal women aged ≥55 years with PAH were matched by age and body mass index to women without cardiovascular disease. Plasma sex hormone levels were measured by immunoassay.Lower levels of DHEA-S (p<0.001) and higher levels of E2 (p=0.02) were associated with PAH. In PAH cases (n=112), lower DHEA-S levels were associated with worse haemodynamics (all p<0.01) and more right ventricular dilatation and dysfunction (both p=0.001). Lower DHEA-S levels were associated with shorter 6-min walking distance (6MWD) (p=0.01) and worse functional class (p=0.004). Each Ln(1 µg·dL-1) decrease in DHEA-S was associated with a doubling in the risk of death (hazard ratio 2.0, 95% CI 1.5-2.7; p<0.001). Higher levels of E2 were associated with shorter 6MWD (p=0.03) and worse functional class (p=0.01).High E2 and low DHEA-S levels are associated with the risk and severity of PAH in post-menopausal women. Hormonal modulation should be studied as a treatment strategy in PAH.


Assuntos
Doenças do Tecido Conjuntivo/complicações , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Cardiopatias Congênitas/complicações , Hipertensão Pulmonar/sangue , Pós-Menopausa/sangue , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Hipertensão Pulmonar/complicações , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Teste de Caminhada
10.
Chest ; 154(4): 925-934, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29679597

RESUMO

The genesis of dyspnea involves the activation of several mechanisms that are mediated and perceived depending on previous experiences, values, emotions, and beliefs. Breathlessness may become unbearable, especially in patients who are terminally ill, whether afflicted by respiratory-, cardiac-, or cancer-related disorders, because of a final stage of a chronic process, an acute event, or both. Compared with pain, palliation of dyspnea has received relatively little attention in clinical practice and the medical literature. This is particularly true when the breathlessness is associated with acute respiratory failure because most of the studies on pharmacologic and nonpharmacologic treatments of respiratory distress have excluded such patients. Assessments of the quality of dying for patients in an ICU consistently show that few patients are considered by family members to breathe comfortably at the end of their life. This review focuses on the management of dyspnea in patients with advanced terminal illness, summarizing clinical trial evidence on pharmacologic and nonpharmacologic interventions available for these patients.


Assuntos
Dispneia/terapia , Assistência Terminal/métodos , Doente Terminal , Benzodiazepinas/uso terapêutico , Diuréticos/uso terapêutico , Humanos , Oxigênio/uso terapêutico
11.
J Crit Care ; 44: 161-167, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29127842

RESUMO

INTRODUCTION: Mechanical ventilatory support is life-saving therapy for patients with respiratory failure in intensive care units (ICU) but is linked to ventilator-associated pneumonia and other nosocomial infections. Interventions that improve the efficiency of weaning from mechanical ventilation may improve patient outcomes. OBJECTIVE: To determine whether inhaled budesonide decreases time-to-weaning in COPD stage 4 difficult-to-wean patients and reduces the release of pro-inflammatory cytokines in ICU patients. MATERIALS AND METHODS: We recruited 55 difficult-to-wean COPD patients (Stage 4) within the ICU of the Masih Daneshvari Hospital. Subjects were randomly assigned to receive inhaled budesonide (0.5mg/day) or placebo (normal saline). Dynamic compliance and BAL cytokines were measured. RESULTS: Budesonide significantly reduced the number of days on MV (days-to-weaning=4.6±1.6days) compared to that seen in the control group (7.2±2.7days, p=0.014). Dynamic compliance was significantly improved in the budesonide group on days 3 (p=0.018) and 5 (p=0.011) The levels of CXCL-8 and IL-6 diminished on days 3-5 after start of budesonide (p<0.05). CONCLUSION: In COPD patients on MV, nebulized budesonide was associated with reduced BAL CXCL8 and IL-6 levels and neutrophil numbers as well as an improvement in ventilatory mechanics and facilitated weaning.


Assuntos
Anti-Inflamatórios/uso terapêutico , Budesonida/uso terapêutico , Mediadores da Inflamação/análise , Doença Pulmonar Obstrutiva Crônica/terapia , Respiração Artificial/métodos , Desmame do Respirador/métodos , Adulto , Idoso , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Citocinas/análise , Feminino , Humanos , Linfócitos/citologia , Macrófagos/citologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia
12.
Thromb Res ; 160: 58-65, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29101791

RESUMO

One of the major contributors to sickle cell disease (SCD) pathobiology is the hemolysis of sickle red blood cells (RBCs), which release free hemoglobin and platelet agonists including adenosine 5'-diphosphate (ADP) into the plasma. While platelet activation/aggregation may promote tissue ischemia and pulmonary hypertension in SCD, modulation of sickle platelet dysfunction remains poorly understood. Calpain-1, a ubiquitous calcium-activated cysteine protease expressed in hematopoietic cells, mediates aggregation of platelets in healthy mice. We generated calpain-1 knockout Townes sickle (SSCKO) mice to investigate the role of calpain-1 in steady state and hypoxia/reoxygenation (H/R)-induced sickle platelet activation and aggregation, clot retraction, and pulmonary arterial hypertension. Using multi-electrode aggregometry, which measures platelet adhesion and aggregation in whole blood, we determined that steady state SSCKO mice exhibit significantly impaired PAR4-TRAP-stimulated platelet aggregation as compared to Townes sickle (SS) and humanized control (AA) mice. Interestingly, the H/R injury induced platelet hyperactivity in SS and SSCKO, but not AA mice, and partially rescued the aggregation defect in SSCKO mice. The PAR4-TRAP-stimulated GPIIb-IIIa (αIIbß3) integrin activation was normal in SSCKO platelets suggesting that an alternate mechanism mediates the impaired platelet aggregation in steady state SSCKO mice. Taken together, we provide the first evidence that calpain-1 regulates platelet hyperactivity in sickle mice, and may offer a viable pharmacological target to reduce platelet hyperactivity in SCD.


Assuntos
Anemia Falciforme/sangue , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/metabolismo , Calpaína/sangue , Ativação Plaquetária/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Feminino , Humanos , Hipóxia/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
13.
J Clin Sleep Med ; 12(11): 1507-1516, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27568901

RESUMO

STUDY OBJECTIVES: To examine the relationship of early initiation of noninvasive ventilation (NIV) with postoperative outcomes in patients with obstructive sleep apnea (OSA) undergoing bariatric surgery. METHODS: We included 5,266 patients with OSA undergoing bariatric surgeries at 161 hospitals in the United States. We defined early postoperative NIV as NIV used on the day of or the day after surgery; this could include prophylactic NIV or NIV used for early signs of respiratory deterioration. We developed a hierarchical model to identify factors associated with early use of NIV. Then, in a propensity matched cohort, we assessed the association between NIV use and outcomes. RESULTS: Overall, 996 patients (18.9%) were treated with early postoperative NIV. Predictors of NIV initiation were: male sex (odds ratio: 1.34, 95% confidence interval 1.14-1.59), older age, chronic obstructive pulmonary disease (COPD; odds ratio 1.39, confidence interval: 1.17-1.64), gastric bypass surgery, short-acting narcotics intravenous on the day of surgery and admission to a hospital with high rate of OSA diagnosis. In a propensity matched analysis, we found no significant association between early initiation of NIV and receipt of invasive mechanical ventilation (IMV) (early NIV 4.5% vs. no NIV 3.8% p = 0.46), cardiovascular complications or mortality. Results were consistent in several sensitivity analyses. CONCLUSIONS: In this large observational study of patients with OSA undergoing bariatric surgery, early postoperative NIV use was not associated with better outcomes including less intubation and mortality. Properly designed controlled trials will be necessary to provide more definitive answers to this important clinical question.


Assuntos
Cirurgia Bariátrica , Ventilação não Invasiva/métodos , Complicações Pós-Operatórias/terapia , Apneia Obstrutiva do Sono/terapia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
14.
Am J Respir Crit Care Med ; 193(10): 1168-75, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26651504

RESUMO

RATIONALE: Recent studies have focused on the role of female sex and estradiol (E2) in pulmonary arterial hypertension (PAH), but it is not known whether sex hormones are risk factors for PAH in men. OBJECTIVES: We performed a case-control study to determine whether hormone levels (E2, dehydroepiandrosterone-sulfate [DHEA-S], and testosterone) are associated with PAH in men. METHODS: Plasma sex hormone levels in men with idiopathic, heritable, or connective tissue disease-associated PAH were compared with those from age- and body mass index-matched men without clinical cardiovascular disease. MEASUREMENTS AND MAIN RESULTS: There were 23 cases with PAH (70% had idiopathic PAH, 65% were functional class III/IV) and 67 control subjects. Higher E2 and E2/testosterone levels were associated with the risk of PAH (odds ratio per 1 ln[E2:testosterone], 6.0; 95% confidence interval, 2.2-16.4; P = 0.001), whereas higher levels of DHEA-S were associated with a reduced risk (odds ratio per 1 ln[DHEA-S], 0.1; 95% confidence interval, 0.0-0.3; P = 0.001). E2 and DHEA-S levels were strong predictors of case status (C statistic for both, 0.82) but testosterone was not (C statistic, 0.53). Higher levels of E2 were associated with shorter 6-minute-walk distances (P = 0.03), whereas higher levels of DHEA-S were associated with lower right atrial pressure (P = 0.02) and pulmonary vascular resistance (P = 0.01) in men with PAH. CONCLUSIONS: Higher levels of E2 and lower levels of DHEA-S were associated with PAH in men. Sex-based differences in sex hormone processing and signaling may contribute to unique phenotypes in pulmonary vascular disease.


Assuntos
Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Hipertensão Pulmonar/sangue , Idoso , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
15.
JACC Heart Fail ; 3(6): 467-474, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26046840

RESUMO

OBJECTIVES: The purpose of this study was to determine the predictors of mortality in patients with pulmonary hypertension (PH) associated with heart failure with preserved ejection fraction (HFpEF). BACKGROUND: PH is commonly associated with HFpEF. The predictors of mortality for patients with these conditions are not well characterized. METHODS: In a prospective cohort of patients with right heart catheterization, we identified 73 adult patients who had pulmonary hypertension due to left heart disease (PH-LHD) associated with HFpEF (left ventricular ejection fraction ≥50% by echocardiography); hemodynamically defined as a mean pulmonary artery pressure ≥25 mm Hg and pulmonary artery wedge pressure >15 mm Hg. PH severity was classified according to the diastolic pressure gradient (DPG). Cox proportional hazards ratios were used to estimate the associations between clinical variables and mortality. Receiver-operating characteristic curves were used to evaluate the ability of hemodynamic measurements to predict mortality. RESULTS: The mean age for study subjects was 69 ± 12 years and 74% were female. Patients classified as having combined post-capillary PH and pre-capillary PH (DPG ≥7) were not at increased risk of death as compared to patients with isolated post-capillary PH (DPG <7). A baseline pulmonary arterial capacitance (PAC) of <1.1 ml/mm Hg was 91% sensitive in predicting mortality, with better discriminatory ability than DPG, transpulmonary gradient, or pulmonary vascular resistance (area under the curve of 0.73, 0.50, 0.45, and 0.37, respectively). Fifty-seven subjects underwent acute vasoreactivity testing with inhaled nitric oxide. Acute vasodilator response by the Rich or Sitbon criteria was not associated with improved survival. CONCLUSIONS: PAC is the best predictor of mortality in our cohort and may be useful in describing phenotypic subgroups among those with PH-LHD associated with HFpEF. Acute vasodilator testing did not predict outcome in our cohort but needs to be further investigated.


Assuntos
Insuficiência Cardíaca/mortalidade , Pressão Propulsora Pulmonar/fisiologia , Idoso , Cateterismo Cardíaco , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia , Curva ROC
16.
J Appl Physiol (1985) ; 119(4): 412-9, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26066827

RESUMO

Anthrax is associated with severe vascular leak, which is caused by the bacterial lethal toxin (LeTx). Pleural effusions and pulmonary edema that occur in anthrax are believed to reflect endothelial injury caused by the anthrax toxin. Since vascular leak can also be observed consistently in rats injected intravenously with LeTx, the latter might present a simple physiologically relevant animal model of acute lung injury (ALI). Such a model could be utilized in evaluating and developing better treatment for ALI or acute respiratory distress syndrome (ARDS), as other available rodent models do not consistently produce the endothelial permeability that is a major component of ARDS. The biological activity of LeTx resides in the lethal factor metalloprotease that specifically degrades MAP kinase kinases (MKKs). Recently, we showed that LeTx inactivation of p38 MAP kinase signaling via degradation of MKK3 in pulmonary vascular endothelial cells can be linked to compromise of the endothelial permeability barrier. LeTx effects were linked specifically to blocking activation of p38 substrate and MAP kinase-activated protein kinase 2 (MAPKAPK2 or MK2) and phosphorylation of the latter's substrate, heat shock protein 27 (HSP27). We have now designed a peptide that directly and specifically activates MK2, causing HSP27 phosphorylation in cells and in vivo. The MK2-activating peptide (MK2-AP) also blocks the effects of LeTx on endothelial barriers in cultured cells and reduces LeTx-induced pulmonary vascular leak in rats. Hence, MK2-AP has the therapeutic potential to counteract anthrax or pulmonary edema and vascular leak due to other causes.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Antígenos de Bactérias , Toxinas Bacterianas , Células Endoteliais/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Pulmão/efeitos dos fármacos , Peptídeos/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Edema Pulmonar/prevenção & controle , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/enzimologia , Animais , Permeabilidade Capilar/efeitos dos fármacos , Células Cultivadas , Citoproteção , Modelos Animais de Doenças , Células Endoteliais/enzimologia , Ativação Enzimática , Proteínas de Choque Térmico HSP27/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Pulmão/irrigação sanguínea , Pulmão/enzimologia , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/enzimologia , Interferência de RNA , Ratos , Ratos Endogâmicos F344 , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
17.
Chest ; 147(3): 847-861, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25732450

RESUMO

OSA is a common yet underdiagnosed disorder encountered in everyday practice. The disease is a unique physiologic stressor that contributes to the development or progression of many other disorders, particularly cardiovascular conditions. The pulmonary circulation is specifically affected by the intermittent hypoxic apneas associated with OSA. The general consensus has been that OSA is associated with pulmonary hypertension (PH), but only in a minority of OSA patients and generally of a mild degree. Consequently, there has been no sense of urgency to screen for either condition when evaluating the other. In this review, we explore available evidence describing the interaction between OSA and PH and seek to better understand underlying pathophysiology. We describe certain groups of patients who have a particular preponderance of OSA and PH. Failure to recognize the mutual additive effects of these disorders can lead to suboptimal patient outcomes. Among patients with PH and OSA, CPAP, the mainstay treatment for OSA, may ameliorate pulmonary pressure elevations, but has not been studied adequately. Conversely, among patients with OSA, PH significantly limits functional capacity and potentially shortens survival; yet, there is no routine screening for PH in patients with OSA. We think it is time to study the interaction between OSA and PH more carefully to identify high-risk subgroups. These would be screened for the presence of combined disorders, facilitating earlier institution of therapy and improving outcomes.


Assuntos
Hipertensão Pulmonar/epidemiologia , Hipertensão Pulmonar/fisiopatologia , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/fisiopatologia , Comorbidade , Pressão Positiva Contínua nas Vias Aéreas , Humanos , Hipertensão Pulmonar/terapia , Estimativa de Kaplan-Meier , Programas de Rastreamento , Prevalência , Apneia Obstrutiva do Sono/terapia , Resultado do Tratamento
18.
Cell Signal ; 26(12): 2818-25, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25218191

RESUMO

Tissue transglutaminase 2 (TG2) is a multifunctional enzyme that cross-links proteins with monoamines such as serotonin (5-hydroxytryptamine, 5-HT) via a transglutamidation reaction, and is associated with pathophysiologic vascular responses. 5-HT is a mitogen for pulmonary artery smooth muscle cells (PASMCs) that has been linked to pulmonary vascular remodeling underlying pulmonary hypertension development. We previously reported that 5-HT-induced PASMC proliferation is inhibited by the TG2 inhibitor monodansylcadaverine (MDC); however, the mechanisms are poorly understood. In the present study we hypothesized that TG2 contributes to 5-HT-induced signaling pathways of PASMCs. Pre-treatment of bovine distal PASMCs with varying concentrations of the inhibitor MDC led to differential inhibition of 5-HT-stimulated AKT and ROCK activation, while p-P38 was unaffected. Concentration response studies showed significant inhibition of AKT activation at 50 µM MDC, along with inhibition of the AKT downstream targets mTOR, p-S6 kinase and p-S6. Furthermore, TG2 depletion by siRNA led to reduced 5-HT-induced AKT activation. Immunoprecipitation studies showed that 5-HT treatment led to increased levels of serotonylated AKT and increased TG2-AKT complex formations which were inhibited by MDC. Overexpression of TG2 point mutant cDNAs in PASMCs showed that the TG2 C277V transamidation mutant blunted 5-HT-induced AKT activation and 5-HT-induced PASMC mitogenesis. Finally, 5-HT-induced AKT activation was blunted in SERT genetic knock-out rat cells, but not in their wild-type counterpart. The SERT inhibitor imipramine similarly blocked AKT activation. These results indicate that TG2 contributes to 5-HT-induced distal PASMC proliferation via promotion of AKT signaling, likely via its serotonylation. Taken together, these results provide new insight into how TG2 may participate in vascular smooth muscle remodeling.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Mitose/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Artéria Pulmonar/citologia , Serotonina/farmacologia , Transglutaminases/metabolismo , Animais , Cadaverina/análogos & derivados , Cadaverina/farmacologia , Bovinos , DNA Complementar/genética , Ativação Enzimática/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Imipramina/farmacologia , Proteínas Mutantes/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Proteína 2 Glutamina gama-Glutamiltransferase , RNA Interferente Pequeno/metabolismo , Ratos , Proteína S6 Ribossômica/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Timidina/metabolismo , Quinases Associadas a rho/metabolismo
19.
Am J Respir Crit Care Med ; 190(8): 855-66, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25162767

RESUMO

Great differences in end-of-life practices in treating the critically ill around the world warrant agreement regarding the major ethical principles. This analysis determines the extent of worldwide consensus for end-of-life practices, delineates where there is and is not consensus, and analyzes reasons for lack of consensus. Critical care societies worldwide were invited to participate. Country coordinators were identified and draft statements were developed for major end-of-life issues and translated into six languages. Multidisciplinary responses using a web-based survey assessed agreement or disagreement with definitions and statements linked to anonymous demographic information. Consensus was prospectively defined as >80% agreement. Definitions and statements not obtaining consensus were revised based on comments of respondents, and then translated and redistributed. Of the initial 1,283 responses from 32 countries, consensus was found for 66 (81%) of the 81 definitions and statements; 26 (32%) had >90% agreement. With 83 additional responses to the original questionnaire (1,366 total) and 604 responses to the revised statements, consensus could be obtained for another 11 of the 15 statements. Consensus was obtained for informed consent, withholding and withdrawing life-sustaining treatment, legal requirements, intensive care unit therapies, cardiopulmonary resuscitation, shared decision making, medical and nursing consensus, brain death, and palliative care. Consensus was obtained for 77 of 81 (95%) statements. Worldwide consensus could be developed for the majority of definitions and statements about end-of-life practices. Statements achieving consensus provide standards of practice for end-of-life care; statements without consensus identify important areas for future research.


Assuntos
Cuidados Críticos/normas , Assistência Terminal/normas , Morte Encefálica , Cuidados Críticos/ética , Cuidados Críticos/métodos , Estado Terminal , Tomada de Decisões , Humanos , Consentimento Livre e Esclarecido/ética , Consentimento Livre e Esclarecido/normas , Unidades de Terapia Intensiva/ética , Unidades de Terapia Intensiva/normas , Cooperação Internacional , Cuidados Paliativos/ética , Cuidados Paliativos/métodos , Cuidados Paliativos/normas , Assistência Terminal/ética , Assistência Terminal/métodos , Suspensão de Tratamento/ética , Suspensão de Tratamento/normas
20.
Am J Respir Crit Care Med ; 188(4): 503-7, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23947517

RESUMO

BACKGROUND: Lung cancer is a common problem seen by pulmonologists. The American Thoracic Society (ATS) and European Respiratory Society (ERS) are professional organizations whose memberships are composed of large numbers of pulmonologists. PURPOSE: This document describes the key role of pulmonologists in the prevention, early diagnosis, and management of lung cancer. METHODS: A committee of ATS and ERS leaders and their oncology groups discussed the activities of pulmonologists in relation to lung cancer in various settings and reviewed available literature on the topic. The content of this statement was approved by the board of directors of both the ATS and ERS. RESULTS: Optimal lung cancer care requires a multidisciplinary team of specialists who care for a significant number of patients on a regular basis. Pulmonologists are responsible for and involved with patients from their initial diagnosis and staging through treatment and restaging. They are often involved with complications, palliative care, and end-of-life care, and thus have an important role in team leadership. CONCLUSIONS: Lung cancer is a disease with high mortality, profound effects on the quality of the lives of patients and their families, and an enormous cost and impact on society. To treat lung cancer optimally, care must be prompt, multidisciplinary, and patient-centered. In the entire process, pulmonologists have a key role. Pulmonologists and their professional societies should also enhance lung cancer research and education to provide better treatment options and patient care.


Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Papel do Médico , Pneumologia , Europa (Continente) , Bolsas de Estudo , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/prevenção & controle , Equipe de Assistência ao Paciente , Pneumologia/educação , Sociedades Médicas , Estados Unidos
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