184 research outputs found
Complex I dysfunction underlies the glycolytic switch in pulmonary hypertensive smooth muscle cells.
ATP is essential for cellular function and is usually produced through oxidative phosphorylation. However, mitochondrial dysfunction is now being recognized as an important contributing factor in the development cardiovascular diseases, such as pulmonary hypertension (PH). In PH there is a metabolic change from oxidative phosphorylation to mainly glycolysis for energy production. However, the mechanisms underlying this glycolytic switch are only poorly understood. In particular the role of the respiratory Complexes in the mitochondrial dysfunction associated with PH is unresolved and was the focus of our investigations. We report that smooth muscle cells isolated from the pulmonary vessels of rats with PH (PH-PASMC), induced by a single injection of monocrotaline, have attenuated mitochondrial function and enhanced glycolysis. Further, utilizing a novel live cell assay, we were able to demonstrate that the mitochondrial dysfunction in PH-PASMC correlates with deficiencies in the activities of Complexes I-III. Further, we observed that there was an increase in mitochondrial reactive oxygen species generation and mitochondrial membrane potential in the PASMC isolated from rats with PH. We further found that the defect in Complex I activity was due to a loss of Complex I assembly, although the assembly of Complexes II and III were both maintained. Thus, we conclude that loss of Complex I assembly may be involved in the switch of energy metabolism in smooth muscle cells to glycolysis and that maintaining Complex I activity may be a potential therapeutic target for the treatment of PH
Metabolic Changes Precede the Development of Pulmonary Hypertension in the Monocrotaline Exposed Rat Lung.
There is increasing interest in the potential for metabolic profiling to evaluate the progression of pulmonary hypertension (PH). However, a detailed analysis of the metabolic changes in lungs at the early stage of PH, characterized by increased pulmonary artery pressure but prior to the development of right ventricle hypertrophy and failure, is lacking in a preclinical animal model of PH. Thus, we undertook a study using rats 14 days after exposure to monocrotaline (MCT), to determine whether we could identify early stage metabolic changes prior to the manifestation of developed PH. We observed changes in multiple pathways associated with the development of PH, including activated glycolysis, increased markers of proliferation, disruptions in carnitine homeostasis, increased inflammatory and fibrosis biomarkers, and a reduction in glutathione biosynthesis. Further, our global metabolic profile data compare favorably with prior work carried out in humans with PH. We conclude that despite the MCT-model not recapitulating all the structural changes associated with humans with advanced PH, including endothelial cell proliferation and the formation of plexiform lesions, it is very similar at a metabolic level. Thus, we suggest that despite its limitations it can still serve as a useful preclinical model for the study of PH
Pulmonary Endothelial Mechanical Sensing and Signaling, a Story of Focal Adhesions and Integrins in Ventilator Induced Lung Injury
Patients with critical illness such as acute lung injury often undergo mechanical ventilation in the intensive care unit. Though lifesaving in many instances, mechanical ventilation often results in ventilator induced lung injury (VILI), characterized by overdistension of lung tissue leading to release of edemagenic agents, which further damage the lung and contribute to the mortality and progression of pulmonary inflammation. The endothelium is particularly sensitive, as VILI associated mechanical stress results in endothelial cytoskeletal rearrangement, stress fiber formation, and integrity loss. At the heart of these changes are integrin tethered focal adhesions (FAs) which participate in mechanosensing, structure, and signaling. Here, we present the known roles of FA proteins including c-Src, talin, FAK, paxillin, vinculin, and integrins in the sensing and response to cyclic stretch and VILI associated stress. Attention is given to how stretch is propagated from the extracellular matrix through integrins to talin and other FA proteins, as well as signaling cascades that include FA proteins, leading to stress fiber formation and other cellular responses. This unifying picture of FAs aids our understanding in an effort to prevent and treat VILI
The threat of the COVID-19 pandemic on reversing global life-saving gains in the survival of childhood cancer: A call for collaborative action from SIOP, IPSO, PROS, WCC, CCI, st jude global, UICC and WHPCA
The COVID-19 pandemic poses an unprecedented health crisis in all socio-economic regions across the globe. While the pandemic has had a profound impact on access to and delivery of health care by all services, it has been particularly disruptive for the care of patients with life-threatening noncommunicable diseases (NCDs) such as the treatment of children and young people with cancer. The reduction in child mortality from preventable causes over the last 50 years has seen childhood cancer emerge as a major unmet health care need. Whilst survival rates of 85% have been achieved in high income countries, this has not yet been translated into similar outcomes for children with cancer in resource-limited settings where survival averages 30%. Launched in 2018, by the World Health Organization (WHO), the Global Initiative for Childhood Cancer (GICC) is a pivotal effort by the international community to achieve at least 60% survival for children with cancer by 2030. The WHO GICC is already making an impact in many countries but the disruption of cancer care during the COVID-19 pandemic threatens to set back this global effort to improve the outcome for children with cancer, wherever they may live. As representatives of the global community committed to fostering the goals of the GICC, we applaud the WHO response to the COVID-19 pandemic, in particular we support the WHO's call to ensure the needs of patients with life threatening NCDs including cancer are not compromised during the pandemic. Here, as collaborative partners in the GICC, we highlight specific areas of focus that need to be addressed to ensure the immediate care of children and adolescents with cancer is not disrupted during the pandemic; and measures to sustain the development of cancer care so the long-term goals of the GICC are not lost during this global health crisis.Fil: Pritchard Jones, Kathy. University College London; Estados UnidosFil: de Abib, Simone C.V.. International Society Of Paediatric Surgical Oncology; Surinam. Universidade Federal de Sao Paulo; BrasilFil: Esiashvili, Natia. University of Emory; Estados UnidosFil: Kaspers, Gertjan J.L.. Princess MĂĄxima Center for Pediatric Oncology; PaĂses BajosFil: Rosser, Jon. No especifĂca;Fil: van Doorninck, John A.. Rocky Mountain Hospital for Children; Estados UnidosFil: Braganca, JoĂŁo M.L.. No especifĂca;Fil: Hoffman, Ruth I.. No especifĂca;Fil: Rodriguez Galindo, Carlos. St Jude Childrenâs Research Hospital; Estados UnidosFil: Adams, Cary. Union for International Cancer Control; SuizaFil: Connor, Stephen R.. Worldwide Hospice Palliative Care Alliance; Estados UnidosFil: Abdelhafeez, Abdelhafeez H.. International Society of Paediatric Surgical Oncology; Suiza. St. Jude Childrenâs Research Hospital; Estados UnidosFil: Bouffet, Eric. University Of Toronto. Hospital For Sick Children; CanadĂĄ. International Society of Paediatric Surgical Oncology; SuizaFil: Howard, Scott C.. International Society of Paediatric Surgical Oncology; Suiza. University of Tennessee; Estados UnidosFil: Challinor, Julia M.. International Society of Paediatric Surgical Oncology; Suiza. University of California; Estados UnidosFil: Hessissen, Laila. Children Hospital of Rabat; Marruecos. International Society of Paediatric Surgical Oncology; SuizaFil: Dalvi, Rashmi B.. Bombay Hospital Institute of Medical Sciences; India. International Society of Paediatric Surgical Oncology; SuizaFil: Kearns, Pamela. International Society of Paediatric Surgical Oncology; SuizaFil: Chantada, Guillermo Luis. International Society of Paediatric Surgical Oncology; Suiza. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Frazier, Lindsay A.. International Society of Paediatric Surgical Oncology; Suiza. Dana-Farber Cancer Institute; Estados UnidosFil: Sullivan, Michael J.. University of Melbourne; Australia. International Society of Paediatric Surgical Oncology; SuizaFil: Schulte, Fiona S.M.. University of Calgary; CanadĂĄ. International Society of Paediatric Surgical Oncology; SuizaFil: Morrissey, Lisa K.. Boston Childrenâs Hospital; Estados Unidos. International Society of Paediatric Surgical Oncology; SuizaFil: Kozhaeva, Olga. European Society for Paediatric Oncology; BĂ©lgicaFil: Luna Fineman, Sandra. Childrenâs Hospital Colorado; Estados Unidos. International Society of Paediatric Oncology; SuizaFil: Khan, Muhammad S.. Tawam Hospital; Emiratos Arabes Unido
Ibrutinib as initial therapy for patients with chronic lymphocytic leukemia
Background: chronic lymphocytic leukemia (CLL) primarily affects older persons who often have coexisting conditions in addition to disease-related immunosuppression and myelosuppression. We conducted an international, open-label, randomized phase 3 trial to compare two oral agents, ibrutinib and chlorambucil, in previously untreated older patients with CLL or small lymphocytic lymphoma. Methods: we randomly assigned 269 previously untreated patients who were 65 years of age or older and had CLL or small lymphocytic lymphoma to receive ibrutinib or chlorambucil. The primary end point was progression-free survival as assessed by an independent review committee. Results: the median age of the patients was 73 years. During a median follow-up period of 18.4 months, ibrutinib resulted in significantly longer progression-free survival than did chlorambucil (median, not reached vs. 18.9 months), with a risk of progression or death that was 84% lower with ibrutinib than that with chlorambucil (hazard ratio, 0.16; P<0.001). Ibrutinib significantly prolonged overall survival; the estimated survival rate at 24 months was 98% with ibrutinib versus 85% with chlorambucil, with a relative risk of death that was 84% lower in the ibrutinib group than in the chlorambucil group (hazard ratio, 0.16; P=0.001). The overall response rate was higher with ibrutinib than with chlorambucil (86% vs. 35%, P<0.001). The rates of sustained increases from baseline values in the hemoglobin and platelet levels were higher with ibrutinib. Adverse events of any grade that occurred in at least 20% of the patients receiving ibrutinib included diarrhea, fatigue, cough, and nausea; adverse events occurring in at least 20% of those receiving chlorambucil included nausea, fatigue, neutropenia, anemia, and vomiting. In the ibrutinib group, four patients had a grade 3 hemorrhage and one had a grade 4 hemorrhage. A total of 87% of the patients in the ibrutinib group are continuing to take ibrutinib. Conclusions: ibrutinib was superior to chlorambucil in previously untreated patients with CLL or small lymphocytic lymphoma, as assessed by progression-free survival, overall survival, response rate, and improvement in hematologic variables. (Funded by Pharmacyclics and others; RESONATE-2 ClinicalTrials.gov number, NCT01722487.)
Self-employment amongst migrant groups: New evidence for England and Wales
Self-employment constitutes a vital part of the economy since entrepreneurs can provide employment not only for themselves but also for others. The link between self-employment and immigration is, however, complex, especially given the changing nature of self-employment. We investigate the evolving relationship between self-employment and immigration using recently released microdata from the 2011 Census for England and Wales. Our findings indicate large variations, with high self-employment rates observed for some groups with a long established history of migration to the UK (especially men born in Pakistan) and also for some groups who have arrived more recently (such as from the EUâs new member states). We further explore the differences, analyse variations by gender and identify key determining factors. In addition to certain socio-economic characteristics, it is found that migration-related influences, such as English language proficiency and period of arrival in the UK, play an important role for some groups
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