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1.
BJOG ; 131(3): 334-342, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37555464

RESUMO

OBJECTIVE: To assess whether aspirin treatment can be discontinued in pregnancies with normal uterine artery pulsatility index (≤90th percentile) at 24-28 weeks. DESIGN: Post-hoc analysis of a clinical trial. SETTING: Nine maternity hospitals in Spain. POPULATION OR SAMPLE: Pregnant individuals at high risk of pre-eclampsia at 11-13 weeks and normal uterine artery Doppler at 24-28 weeks. METHODS: All participants received treatment with daily aspirin at a dose of 150 mg. Participants were randomly assigned, in a 1:1 ratio, either to continue aspirin treatment until 36 weeks (control group) or to discontinue aspirin treatment (intervention group), between September 2019 and September 2021. In this secondary analysis, women with a UtAPI >90th percentile at 24-28 weeks were excluded. The non-inferiority margin was set at a difference of 1.9% for the incidence of preterm pre-eclampsia. MAIN OUTCOME MEASURES: Incidence of preterm pre-eclampsia. RESULTS: Of the 1611 eligible women, 139 were excluded for UtAPI >90th percentile or if UtAPI was not available. Finally, 804 were included in this post-hoc analysis. Preterm pre-eclampsia occurred in three of 409 (0.7%) women in the aspirin discontinuation group and five of 395 (1.3%) women in the continuation group (-0.53; 95% CI -1.91 to 0.85), indicating non-inferiority of aspirin discontinuation. CONCLUSIONS: Discontinuing aspirin treatment at 24-28 weeks in women with a UtAPI ≤90th percentile was non-inferior to continuing aspirin treatment until 36 weeks for preventing preterm pre-eclampsia.


Assuntos
Aspirina , Pré-Eclâmpsia , Feminino , Humanos , Recém-Nascido , Gravidez , Aspirina/uso terapêutico , Pré-Eclâmpsia/prevenção & controle , Pré-Eclâmpsia/tratamento farmacológico , Ultrassonografia Doppler , Artéria Uterina/diagnóstico por imagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
2.
JAMA ; 329(7): 542-550, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36809321

RESUMO

Importance: Aspirin reduces the incidence of preterm preeclampsia by 62% in pregnant individuals at high risk of preeclampsia. However, aspirin might be associated with an increased risk of peripartum bleeding, which could be mitigated by discontinuing aspirin before term (37 weeks of gestation) and by an accurate selection of individuals at higher risk of preeclampsia in the first trimester of pregnancy. Objective: To determine whether aspirin discontinuation in pregnant individuals with normal soluble fms-like tyrosine kinase-1 to placental growth factor (sFlt-1:PlGF) ratio between 24 and 28 weeks of gestation was noninferior to aspirin continuation to prevent preterm preeclampsia. Design, Setting, and Participants: Multicenter, open-label, randomized, phase 3, noninferiority trial conducted in 9 maternity hospitals across Spain. Pregnant individuals (n = 968) at high risk of preeclampsia during the first-trimester screening and an sFlt-1:PlGF ratio of 38 or less at 24 to 28 weeks of gestation were recruited between August 20, 2019, and September 15, 2021; of those, 936 were analyzed (intervention: n = 473; control: n = 463). Follow-up was until delivery for all participants. Interventions: Enrolled patients were randomly assigned in a 1:1 ratio to aspirin discontinuation (intervention group) or aspirin continuation until 36 weeks of gestation (control group). Main Outcomes and Measures: Noninferiority was met if the higher 95% CI for the difference in preterm preeclampsia incidences between groups was less than 1.9%. Results: Among the 936 participants, the mean (SD) age was 32.4 (5.8) years; 3.4% were Black and 93% were White. The incidence of preterm preeclampsia was 1.48% (7/473) in the intervention group and 1.73% (8/463) in the control group (absolute difference, -0.25% [95% CI, -1.86% to 1.36%]), indicating noninferiority. Conclusions and Relevance: Aspirin discontinuation at 24 to 28 weeks of gestation was noninferior to aspirin continuation for preventing preterm preeclampsia in pregnant individuals at high risk of preeclampsia and a normal sFlt-1:PlGF ratio. Trial Registration: ClinicalTrials.gov Identifier: NCT03741179 and ClinicalTrialsRegister.eu Identifier: 2018-000811-26.


Assuntos
Aspirina , Pré-Eclâmpsia , Nascimento Prematuro , Suspensão de Tratamento , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Biomarcadores/sangue , Hemorragia/sangue , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Período Periparto , Fator de Crescimento Placentário/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/prevenção & controle , Complicações na Gravidez/sangue , Complicações na Gravidez/induzido quimicamente , Complicações na Gravidez/prevenção & controle , Primeiro Trimestre da Gravidez , Nascimento Prematuro/sangue , Nascimento Prematuro/prevenção & controle , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue
3.
Minerva Surg ; 77(3): 199-204, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34338465

RESUMO

BACKGROUND: The COVID-19 pandemic has made us to respond to the needs of the community. Telemedicine has gained worldwide acceptance. We describe our experience with teleconsultation in surgical patients during the first wave of the COVID-19 pandemic and evaluate patient satisfaction and the feasibility of maintaining it as a future strategy in selected patients. METHODS: An observational, retrospective, single-site cohort study was carried out by reviewing electronic medical records and conducting a telephone survey. RESULTS: During this time, 1706 teleconsultations have been carried out: 59.5% of patients were rescheduled, 26.1% have been solved and of these 57.3% (255 patients) have been discharged; 12.19% were not contacted. The 73.6% considered that teleconsultation was able to fully or partially resolve the reason for their medical appointment; 61.6% were willing to continue with teleconsultation; 15.2% of the patients needed some kind of help or required a second call to speak with a family member, and 37.2% would prefer a face-to-face visit because of difficulties with the teleconsultation. The overall satisfaction was 8.7 out of 10. CONCLUSIONS: Telemedicine has demonstrated to be a useful tool even for surgical patients during COVID-19 pandemic. A high proportion of patients can be managed by telephone call. Patients reported a high degree of satisfaction. Teleconsultation is a feasible strategy not also during the current COVID-19 pandemic but also for future.


Assuntos
COVID-19/epidemiologia , Satisfação do Paciente , Consulta Remota , SARS-CoV-2 , Estudos de Coortes , Estudos de Viabilidade , Humanos , Pandemias , Satisfação do Paciente/estatística & dados numéricos , Consulta Remota/normas , Consulta Remota/tendências , Estudos Retrospectivos
4.
Neurology ; 98(3): e260-e266, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795049

RESUMO

BACKGROUND AND OBJECTIVES: To understand patterns of care and circumstances surrounding end of life in patients with intracranial gliomas. METHODS: We retrospectively analyzed end-of-life circumstances in patients with intracranial high-grade gliomas at Columbia University Irving Medical Center who died from January 2014 to February 2019, including cause of death, location of death, and implementation of comfort measures and resuscitative efforts. RESULTS: There were 152 patients (95 men, 57 women; median age at death 61.5 years, range 24-87 years) who died from January 2014 to February 2019 with adequate data surrounding end-of-life circumstances. Clinical tumor progression (n = 117, 77.0%) was the most common cause of death, with all patients transitioned to comfort measures. Other causes included, but were not limited to, infection (19, 12.5%); intratumoral hemorrhage (5, 3.3%); seizures (8, 5.3%); cerebral edema (4, 2.6%); pulmonary embolism (4, 2.6%); autonomic failure (2, 1.3%); and hemorrhagic shock (2, 1.3%). Multiple mortal events were identified in 10 (8.5%). Seventy-three patients (48.0%) died at home with hospice. Other locations were inpatient hospice (40, 26.3%); acute care hospital (34, 22.4%), including 27 (17.8%) with and 7 (4.6%) without comfort measures; skilled nursing facility (4, 3.3%), including 3 (2.0%) with and 1 (0.7%) without comfort measures; or religious facility (1, 0.7%) with comfort measures. Acute cardiac or pulmonary resuscitation was performed in 20 patients (13.2%). DISCUSSION: Clinical tumor progression was the most common (77.0%) cause of death, followed by infection (12.5%). Hospice or comfort measures were ultimately implemented in 94.7% of patients, although resuscitation was performed in 13.2%. Improved understanding of circumstances surrounding death, frequency of use of hospice services, and frequency of resuscitative efforts in patients with gliomas may allow physicians to more accurately discuss end-of-life expectations with patients and caregivers, facilitating informed care planning.


Assuntos
Glioma , Cuidados Paliativos na Terminalidade da Vida , Assistência Terminal , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Feminino , Glioma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Surgery ; 171(4): 932-939, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736792

RESUMO

BACKGROUND: Bone disease in primary hyperparathyroidism is a clear indication for surgical treatment. However, it is not known whether surgery benefits hypercalcemic primary hyperparathyroidism and normocalcemic primary hyperparathyroidism equally. The aim of our study was to evaluate the bone changes in patients undergoing parathyroidectomy based on the biochemical profile 1 and 2 years after surgery. METHODS: This prospective study included 87 consecutive patients diagnosed with primary hyperparathyroidism who underwent surgery between 2016 and 2018. Bone densitometry (1/3 distal radius, lumbar, and femur) and bone remodeling markers (osteocalcin, type 1 procollagen [P1NP], ß-cross-linked telopeptide of type I collagen [BCTX]) were performed preoperatively and postoperatively. Postoperative changes in bone mineral density and bone markers were compared and evaluated according to the clinical characteristics and the individual biochemical profile. RESULTS: One year after surgery, all patients showed an increase in bone mineral density at the lumbar site (mean, 0.029 g/cm2; range, 0.017-0.04; P < .001) and femur neck (mean, 0.025 g/cm2; range, 0.002-0.05; P < .001); however, there were no changes in the distal third of the radius (mean, -0.003 g/cm2; range, -0.008 to 0.002; P = NS). There were no significant differences when comparing normocalcemic primary hyperparathyroidism and hypercalcemic primary hyperparathyroidism. Serum osteocalcin (37 ± 17.41), P1NP (67.53 ± 31.81) and BCTX (0.64 ± 0.37) levels were elevated before surgery. One year after the surgery, we observed a significant decrease in P1NP (33.05 ± 13.16, P = .001), osteocalcin (15.80 ± 6.19, P = .001), and BCTX (0.26 ± 0.32, P < .001) levels. CONCLUSION: Our findings indicate that parathyroidectomy has similar benefits for normocalcemic primary hyperparathyroidism and hypercalcemic primary hyperparathyroidism in terms of bone improvement. Although the most substantial improvement occurred during the first postoperative year in both groups, we consider that studies with longer follow-up are warranted.


Assuntos
Hipercalcemia , Hiperparatireoidismo Primário , Densidade Óssea , Cálcio , Colágeno Tipo I , Humanos , Hipercalcemia/cirurgia , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/cirurgia , Osteocalcina , Hormônio Paratireóideo , Paratireoidectomia , Estudos Prospectivos
6.
Cir Cir ; 89(S2): 1-3, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932529

RESUMO

Involvement of the thyroid gland by tuberculosis is very rare and is usually secondary to disseminated infection. Very few cases of primary thyroid tuberculosis have been described even in countries with a high incidence of this disease. We present the case of a Spanish patient operated for a suspicious thyroid nodule that was finally diagnosed as primary thyroid tuberculosis.


La afectación de la glándula tiroidea por tuberculosis es muy rara y generalmente es secundaria a una enfermedad ­diseminada. Se han descrito muy pocos casos de tuberculosis tiroidea primaria incluso en paises con alta incidencia de esta enfermedad. Presentamos el caso de una paciente española operada por un nódulo tiroideo sospechoso que fue finalmente diagnosticado como tuberculosis tiroidea primaria.


Assuntos
Glândula Tireoide , Tuberculose , Humanos , Incidência , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/cirurgia
7.
Free Radic Biol Med ; 175: 56-64, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34058321

RESUMO

PB125® is a phytochemical composition providing potent Nrf2 activation as well as a number of direct actions that do not involve Nrf2. Nrf2 is a transcription actor that helps maintain metabolic balance by providing redox-sensitive expression of numerous genes controlling normal day-to-day metabolic pathways. When ordinary metabolism is upset by extraordinary events such as injury, pathogenic infection, air or water pollution, ingestion of toxins, or simply by the slow but incessant changes brought about by aging and genetic variations, Nrf2 may also be called into action by the redox changes resulting from these events, whether acute or chronic. A complicating factor in all of this is that Nrf2 levels decline with aging, leaving the elderly less able to maintain proper redox balance. The dysregulated gene expression that results can cause or exacerbate a wide variety of pathological conditions, including susceptibility to viral infections. This review examines the characteristics desirable in Nrf2 activators that have therapeutic potential, as well as some of the patterns of dysregulated gene expression commonly observed during pulmonary infections and the normalizing effects possible by judicious use of phytochemicals to increase the activation level of available Nrf2.


Assuntos
COVID-19 , Fator 2 Relacionado a NF-E2 , Abietanos/farmacologia , Idoso , Humanos , Fator 2 Relacionado a NF-E2/genética , SARS-CoV-2
8.
mBio ; 12(2)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879587

RESUMO

Since nontuberculous mycobacteria (NTM) are pervasive in the environment and NTM infections are relatively uncommon, underlying hereditary or acquired host susceptibility factors should be sought for in most NTM-infected patients. To facilitate identification of underlying risk factors, it is useful to classify NTM disease into skin-soft tissue infections, isolated NTM lung disease, and extrapulmonary visceral/disseminated disease because the latter two categories have unique sets of underlying host risk factors. Nakajima and coworkers (M. Nakajima, M. Matsuyama, M. Kawaguchi, T. Kiwamoto, et al., mBio 12:e01947-20, 2021, https://doi.org/10.1128/mBio.01947-20) in a recent issue of mBio found that Nrf2 (nuclear factor erythroid 2-related factor 2), a transcription factor that is induced by oxidative stress but induces antioxidant molecules, provides protection against an NTM infection in a murine model. While they showed that Nrf2 induction of Nramp-1 enhanced phagosome-lysosome fusion, we discuss other potential mechanisms by which oxidative stress predisposes to and Nrf2 protects against NTM infections.


Assuntos
Ativação de Macrófagos , Infecções por Mycobacterium não Tuberculosas , Animais , Granuloma , Humanos , Camundongos , Mycobacterium avium , Fator 2 Relacionado a NF-E2 , Micobactérias não Tuberculosas
9.
Neurooncol Adv ; 2(1): vdaa069, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32666048

RESUMO

BACKGROUND: Tumor Treating Fields (TTF) have entered clinical practice for newly diagnosed and recurrent glioblastoma (GGM). However, controversies remain unresolved with regard to appropriate usage. We sought to determine TTF usage in major academic neuro-oncology programs in New York City, USA and Heidelberg, Germany and understand current attitudes toward TTF usage among providers. METHODS: We retrospectively determined TTF usage among patients with GGM, before and since the publication of key clinical trial results and regulatory approvals. We also surveyed attendees of an educational session related to TTF during the 2019 American Society of Clinical Oncology annual meeting. RESULTS: TTF usage remains infrequent (3-12% of patients with newly diagnosed GBM, and 0-16% of patients with recurrent disease) in our practices, although it has increased over time. Among 30 survey respondents (77% of whom self-identified as neuro- or medical oncologists), 60% were convinced that TTF prolongs survival for newly diagnosed GGM despite published phase III data and regulatory approval, and only 30% viewed TTF as definitively part of the standard of care treatment. A majority (87%) opposed mandating TTF incorporation into the design of clinical trials. CONCLUSIONS: Providers continue to view TTF with some level of skepticism, with a lack of additional supportive data and logistical concerns representing continued barriers to uptake.

10.
bioRxiv ; 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32511372

RESUMO

Nrf2 is a transcription factor that regulates cellular redox balance and the expression of a wide array of genes involved in immunity and inflammation, including antiviral actions. Nrf2 activity declines with age, making the elderly more susceptible to oxidative stress-mediated diseases, which include type 2 diabetes, chronic inflammation, and viral infections. Published evidence suggests that Nrf2 activity may regulate important mechanisms affecting viral susceptibility and replication. We examined gene expression levels by GeneChip microarray and by RNA-seq assays. We found that the potent Nrf2 activating composition PB125® downregulates ACE2 and TMPRSS2 mRNA expression in human liver-derived HepG2 cells. ACE2 is a surface receptor and TMPRSS2 activates the spike protein for SARS-Cov-2 entry into host cells. Furthermore, in endotoxin-stimulated primary human pulmonary artery endothelial cells we report the marked downregulation by PB125 of 36 genes encoding cytokines. These include IL1-beta, IL6, TNF-α the cell adhesion molecules ICAM1, VCAM1, and E-selectin, and a group of IFN-γ-induced genes. Many of these cytokines have been specifically identified in the "cytokine storm" observed in fatal cases of COVID-19, suggesting that Nrf2 activation may significantly decrease the intensity of the storm.

11.
Antioxidants (Basel) ; 9(6)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545518

RESUMO

Nrf2 is a transcription factor that regulates cellular redox balance and the expression of a wide array of genes involved in immunity and inflammation, including antiviral actions. Nrf2 activity declines with age, making the elderly more susceptible to oxidative stress-mediated diseases, which include type 2 diabetes, chronic inflammation, and viral infections. Published evidence suggests that Nrf2 activity may regulate important mechanisms affecting viral susceptibility and replication. We examined gene expression levels by GeneChip microarray and by RNA-seq assays. We found that the potent Nrf2-activating composition PB125® downregulates ACE2 and TMPRSS2 mRNA expression in human liver-derived HepG2 cells. ACE2 is a surface receptor and TMPRSS2 activates the spike protein for SARS-CoV-2 entry into host cells. Furthermore, in endotoxin-stimulated primary human pulmonary artery endothelial cells, we report the marked downregulation by PB125 of 36 genes encoding cytokines. These include IL-1-beta, IL-6, TNF-α, the cell adhesion molecules ICAM-1, VCAM-1, and E-selectin, and a group of IFN-γ-induced genes. Many of these cytokines have been specifically identified in the "cytokine storm" observed in fatal cases of COVID-19, suggesting that Nrf2 activation may significantly decrease the intensity of the storm.

12.
Int J Mol Sci ; 21(9)2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32392789

RESUMO

The HIV-infected population is at a dramatically increased risk of developing pulmonary arterial hypertension (PAH), a devastating and fatal cardiopulmonary disease that is rare amongst the general population. It is increasingly apparent that PAH is a disease with complex and heterogeneous cellular and molecular pathologies, and options for therapeutic intervention are limited, resulting in poor clinical outcomes for affected patients. A number of soluble HIV factors have been implicated in driving the cellular pathologies associated with PAH through perturbations of various signaling and regulatory networks of uninfected bystander cells in the pulmonary vasculature. While these mechanisms are likely numerous and multifaceted, the overlapping features of PAH cellular pathologies and the effects of viral factors on related cell types provide clues as to the potential mechanisms driving HIV-PAH etiology and progression. In this review, we discuss the link between the DNA damage response (DDR) signaling network, chronic HIV infection, and potential contributions to the development of pulmonary arterial hypertension in chronically HIV-infected individuals.


Assuntos
Dano ao DNA , Infecções por HIV/complicações , Hipertensão Arterial Pulmonar/diagnóstico , Infecções por HIV/diagnóstico , Humanos , Hipertensão Arterial Pulmonar/etiologia , Fatores de Risco , Transdução de Sinais
13.
Free Radic Biol Med ; 147: 102-113, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31863909

RESUMO

Redox imbalance results in damage to cellular macromolecules and interferes with signaling pathways, leading to an inflammatory cellular and tissue environment. As such, the cellular oxidative environment is tightly regulated by several redox-modulating pathways. Many viruses have evolved intricate mechanisms to manipulate these pathways for their benefit, including HIV-1, which requires a pro-oxidant cellular environment for optimal replication. One such virulence factor responsible for modulating the redox environment is the HIV Transactivator of transcription (Tat). Tat is of particular interest as it is actively secreted by infected cells and internalized by uninfected bystander cells where it can elicit pro-oxidant effects resulting in inflammation and damage. Previously, we demonstrated that Tat regulates basal expression of Superoxide Dismutase 2 (sod2) by altering the binding of the Sp-transcription factors at regions relatively near (approx. -210 nucleotides) upstream of the transcriptional start site. Now, using in silico analysis and a series of sod2 promoter reporter constructs, we have identified putative clusters of Sp-binding sites located further upstream of the proximal sod2 promoter, between nucleotides -3400 to -210, and tested their effect on basal transcription and for their sensitivity to HIV-1 Tat. In this report, we demonstrate that under basal conditions, maximal transcription requires a cluster of Sp-binding sites in the -584 nucleotide region, which is extremely sensitive to Tat. Using chromatin immunoprecipitation (ChIP) we demonstrate that Tat results in altered occupancy of Sp1 and Sp3 at this distal Tat-sensitive regulatory element and strongly stimulated endogenous expression of SOD2 in human pulmonary artery endothelial cells (HPAEC). We also report altered expression of Sp1 and Sp3 in Tat-expressing HPAEC as well as in the lungs of HIV-1 infected humanized mice. Lastly, Tat co-immunoprecipitated with endogenous Sp3 but not Sp1 and did not alter the acetylation state of Sp3. Thus, here, we have defined a novel and important cis-acting factor in HIV-1 Tat-mediated regulation of SOD2, demonstrated that modulation of Sp1 and Sp3 activity by Tat promotes SOD2 expression in primary human pulmonary artery endothelial cells and determined that pulmonary levels of Sp3 as well as SOD2 are increased in the lungs of a mouse model of HIV infection.


Assuntos
Células Endoteliais , Infecções por HIV , Animais , Sítios de Ligação , Células Endoteliais/metabolismo , Produtos do Gene tat , Infecções por HIV/genética , Humanos , Camundongos , Ligação Proteica , Artéria Pulmonar/metabolismo , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3 , Superóxido Dismutase , Produtos do Gene tat do Vírus da Imunodeficiência Humana
14.
Free Radic Biol Med ; 141: 244-252, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31238128

RESUMO

Chronic HIV infection in the era of anti-retroviral therapy is associated with dramatically increased risk of developing severe cardio pulmonary disease. Common to these diseases is increased oxidative burden and chronic inflammation despite low viremia and restoration of CD4+ T-cell levels. Soluble viral factors are heavily implicated in these disease processes, including the HIV Transactivator of Transcription (Tat). Tat is produced in high levels during infection and secreted from infected cells into circulation where it is internalized by bystander cells and is known to regulate inflammatory pathways and elicit a pro-oxidant environment. We have examined the effects of Tat on the anti-oxidant regulatory network driven by the transcription factor Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in primary human pulmonary arterial endothelial cells, which are heavily involved in pathogenesis of HIV associated lung diseases including pulmonary arterial hypertension and COPD. Co-expression of Tat and a luciferase reporter construct driven by the Nrf2 activated anti-oxidant response element (ARE) demonstrated markedly reduced Nrf2/ARE activity, even when stimulated by the potent Nrf2 activating compound PB125. Additionally, Heme-oxygenase-1 (HO-1) transcription was potently repressed by Tat in a cell line as well as primary endothelial cells, and treatment with PB125 failed to restore transcriptional activity. Other anti-oxidant Nrf2 genes examined included NADPH Dehydrogenase Quinone 1 (NQO1) and Sulfiredoxin-1 (SRXN1). NQO1 was repressed basally by Tat, while SRXN1 transcription was refractory to activation by PB125 in the presence of Tat. Lastly, we demonstrated that Tat expressing cells have increased indicators of oxidative stress including elevated production of reactive oxygen species, measured by electron paramagnetic resonance spectroscopy, and increased levels of nitrotyrosine content. These observations suggest a novel mechanism by which HIV Tat increases oxidative burden by dysregulation of the Nrf2/ARE pathway.


Assuntos
Antioxidantes/metabolismo , Infecções por HIV/genética , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Elementos de Resposta Antioxidante/genética , Linhagem Celular , Células Endoteliais/virologia , HIV/genética , HIV/patogenicidade , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Heme Oxigenase-1/genética , Humanos , NAD(P)H Desidrogenase (Quinona)/genética , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo
15.
Nature ; 505(7483): 412-6, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24317696

RESUMO

Respiratory surfaces are exposed to billions of particulates and pathogens daily. A protective mucus barrier traps and eliminates them through mucociliary clearance (MCC). However, excessive mucus contributes to transient respiratory infections and to the pathogenesis of numerous respiratory diseases. MUC5AC and MUC5B are evolutionarily conserved genes that encode structurally related mucin glycoproteins, the principal macromolecules in airway mucus. Genetic variants are linked to diverse lung diseases, but specific roles for MUC5AC and MUC5B in MCC, and the lasting effects of their inhibition, are unknown. Here we show that mouse Muc5b (but not Muc5ac) is required for MCC, for controlling infections in the airways and middle ear, and for maintaining immune homeostasis in mouse lungs, whereas Muc5ac is dispensable. Muc5b deficiency caused materials to accumulate in upper and lower airways. This defect led to chronic infection by multiple bacterial species, including Staphylococcus aureus, and to inflammation that failed to resolve normally. Apoptotic macrophages accumulated, phagocytosis was impaired, and interleukin-23 (IL-23) production was reduced in Muc5b(-/-) mice. By contrast, in mice that transgenically overexpress Muc5b, macrophage functions improved. Existing dogma defines mucous phenotypes in asthma and chronic obstructive pulmonary disease (COPD) as driven by increased MUC5AC, with MUC5B levels either unaffected or increased in expectorated sputum. However, in many patients, MUC5B production at airway surfaces decreases by as much as 90%. By distinguishing a specific role for Muc5b in MCC, and by determining its impact on bacterial infections and inflammation in mice, our results provide a refined framework for designing targeted therapies to control mucin secretion and restore MCC.


Assuntos
Pulmão/imunologia , Mucina-5B/metabolismo , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Animais , Asma/imunologia , Asma/metabolismo , Infecções Bacterianas/imunologia , Infecções Bacterianas/microbiologia , Cílios/fisiologia , Orelha Média/imunologia , Orelha Média/microbiologia , Feminino , Inflamação/patologia , Pulmão/metabolismo , Pulmão/microbiologia , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Mucina-5AC/deficiência , Mucina-5AC/metabolismo , Mucina-5B/deficiência , Mucina-5B/genética , Fagocitose , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/microbiologia , Staphylococcus aureus/imunologia , Análise de Sobrevida
16.
Am J Respir Crit Care Med ; 187(10): 1110-7, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23392441

RESUMO

RATIONALE: Lung infections caused by opportunistic or virulent pathogens are a principal cause of morbidity and mortality in HIV infection. It is unknown whether HIV infection leads to changes in basal lung microflora, which may contribute to chronic pulmonary complications that increasingly are being recognized in individuals infected with HIV. OBJECTIVES: To determine whether the immunodeficiency associated with HIV infection resulted in alteration of the lung microbiota. METHODS: We used 16S ribosomal RNA targeted pyrosequencing and shotgun metagenomic sequencing to analyze bacterial gene sequences in bronchoalveolar lavage (BAL) and mouths of 82 HIV-positive and 77 HIV-negative subjects. MEASUREMENTS AND MAIN RESULTS: Sequences representing Tropheryma whipplei, the etiologic agent of Whipple's disease, were significantly more frequent in BAL of HIV-positive compared with HIV-negative individuals. T. whipplei dominated the community (>50% of sequence reads) in 11 HIV-positive subjects, but only 1 HIV-negative individual (13.4 versus 1.3%; P = 0.0018). In 30 HIV-positive individuals sampled longitudinally, antiretroviral therapy resulted in a significantly reduced relative abundance of T. whipplei in the lung. Shotgun metagenomic sequencing was performed on eight BAL samples dominated by T. whipplei 16S ribosomal RNA. Whole genome assembly of pooled reads showed that uncultured lung-derived T. whipplei had similar gene content to two isolates obtained from subjects with Whipple's disease. CONCLUSIONS: Asymptomatic subjects with HIV infection have unexpected colonization of the lung by T. whipplei, which is reduced by effective antiretroviral therapy and merits further study for a potential pathogenic role in chronic pulmonary complications of HIV infection.


Assuntos
Infecções por HIV/complicações , Pulmão/microbiologia , Tropheryma , Doença de Whipple/complicações , Doença de Whipple/microbiologia , Estudos de Coortes , Humanos , Estudos Longitudinais
17.
Free Radic Biol Med ; 51(9): 1697-707, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21855628

RESUMO

Chronic human immunodeficiency virus infection is associated with higher incidence of pulmonary complications including hypertension, vasculopathy, lymphocytic alveolitis, and interstitial pneumonitis not attributed to either opportunistic infections or presence of the virus. The Tat (transactivator of transcription) protein, a required transactivator for expression of full-length viral genes, is pleiotropic and influences expression of cellular inflammatory genes. Tat-dependent transactivation of cellular genes requires specific mediators, including NF-κB, widely recognized as sensitive to changes in cellular oxidant burden. We hypothesized that overproduction of Tat leads to increased oxidant burden and to alterations in basal inflammatory status as measured by NF-κB activation. We engineered transgenic mouse lines that express Tat (86-amino-acid isoform) in the lung under the control of the surfactant protein C promoter. Tat-transgenic mice exhibit increased pulmonary cellular infiltration, increased nitrotyrosine and carbonyl protein modifications, and increased levels of NF-κB, MnSOD, and thioredoxin-interacting protein. These data indicate that Tat increases oxidant burden and resets the threshold for inflammation, which may increase susceptibility to secondary injuries.


Assuntos
Produtos do Gene tat/genética , Produtos do Gene tat/metabolismo , HIV-1 , Pulmão/metabolismo , Estresse Oxidativo , Animais , Feminino , Técnicas de Transferência de Genes , Inflamação/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Transgênicos , NF-kappa B/metabolismo
20.
Am J Respir Crit Care Med ; 174(4): 437-45, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16728715

RESUMO

RATIONALE: HIV-infected patients with pulmonary arterial hypertension have histologic manifestations that are indistinguishable from those found in patients with idiopathic pulmonary arterial hypertension. In addition, the role of pleiotropic viral proteins in the development of plexiform lesions in HIV-related pulmonary hypertension (HRPH) has not been explored. Simian immunodeficiency virus (SIV) infection of macaques has been found to closely recapitulate many of the characteristic features of HIV infection, and thus hallmarks of pulmonary arterial hypertension should also be found in this nonhuman primate model of HIV. OBJECTIVES: To determine whether pulmonary arterial lesions were present in archived SIV-infected macaque lung tissues from Johns Hopkins University and two National Primate Research Centers. METHODS: Archived macaque and human lung sections were examined via immunohistochemistry for evidence of complex vascular lesions. RESULTS: Complex plexiform-like lesions characterized by lumenal obliteration, intimal disruption, medial hypertrophy, thrombosis, and recanalized lumena were found exclusively in animals infected with SHIV-nef (a chimeric viral construct containing the HIV nef gene in an SIV backbone), but not in animals infected with SIV. The mass of cells in the lesions were factor VIII positive, and contained cells positive for muscle-specific and smooth muscle actins. Lung mononuclear cells were positive for HIV Nef, suggesting viral replication. Endothelial cells in both the SHIV-nef macaques and patients with HRPH, but not in patients with idiopathic pulmonary arterial hypertension, were also Nef positive. CONCLUSIONS: The discovery of complex vascular lesions in SHIV-nef- but not SIV-infected animals, and the presence of Nef in the vascular cells of patients with HRPH, suggest that Nef plays a key role in the development of severe pulmonary arterial disease.


Assuntos
Produtos do Gene nef/fisiologia , HIV-1/genética , Hipertensão Pulmonar/genética , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Proteínas Virais Reguladoras e Acessórias/genética , Animais , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Imunofluorescência , HIV-1/fisiologia , Humanos , Imuno-Histoquímica , Macaca , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/patogenicidade , Replicação Viral , Produtos do Gene nef do Vírus da Imunodeficiência Humana
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