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Parikh R, Farber HW. Response to "Derivation and validation of a noninvasive prediction tool to identify pulmonary hypertension in patients with IPF: Evolution of the model FORD" by Nathan et al. J Heart Lung Transplant 2024; 43:691-692. [PMID: 38158103 DOI: 10.1016/j.healun.2023.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024] Open
Affiliation(s)
- R Parikh
- Division of Pulmonary, Critical Care and Sleep Medicine, Hartford Hospital, Hartford, Connecticut.
| | - H W Farber
- Division of Pulmonary, Sleep and Critical Care Medicine, Tufts Medical Center, Boston, Massachusetts
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Parikh R, Konstantinidis I, O'Sullivan DM, Farber HW. Pulmonary Hypertension in patients with Interstitial Lung Disease: a tool for early detection. Pulm Circ 2022; 12:e12141. [PMID: 36225536 PMCID: PMC9531548 DOI: 10.1002/pul2.12141] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/25/2022] [Accepted: 09/16/2022] [Indexed: 11/24/2022] Open
Abstract
Pulmonary hypertension (PH) complicates the treatment of interstitial lung disease (ILD) patients resulting in poor functional status and worse outcomes. Early recognition of PH in ILD is important for initiating therapy and considering lung transplantation. However, no standard exists regarding which patients to screen for PH‐ILD or the optimal method to do so. The aim of this study was to create a risk assessment tool that could reliably predict PH in ILD patients. We developed a PH‐ILD Detection tool that incorporated history, exam, 6‐min walk distance, diffusion capacity for carbon monoxide, chest imaging, and cardiac biomarkers to create an eight‐component score. This tool was analyzed retrospectively in 154 ILD patients where each patient was given a score ranging from 0 to 12. The sensitivity (SN) and specificity (SP) of the PH‐ILD Detection tool and an area‐under‐the‐curve (AUC) were calculated. In this cohort, 74 patients (48.1%) had PH‐ILD. A score of ≥6 on the PH‐ILD Detection tool was associated with a diagnosis of PH‐ILD (SN: 86.5%; SP: 86.3%; area‐under‐the‐curve: 0.920, p < 0.001). The PH‐ILD Detection tool provides high SN and SP for detecting PH in ILD patients. With confirmation in larger cohorts, this tool could improve the diagnosis of PH in ILD and may suggest further testing with right heart catheterization and earlier intervention with inhaled treprostinil and/or lung transplant evaluation.
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Affiliation(s)
- R Parikh
- Division of Pulmonary, Critical Care and Sleep Hartford Hospital Hartford CT
| | - I Konstantinidis
- Department of Internal Medicine University of Connecticut Farmington CT
| | - DM O'Sullivan
- Department of Research Administration Hartford HealthCare Hartford CT
| | - HW Farber
- Division of Pulmonary, Sleep and Critical Care Medicine Tufts Medical Center Boston MA
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Emad Y, Ragab Y, Kechida M, Guffroy A, Kindermann M, Robinson C, Erkan D, Frikha F, Ibrahim O, Al-Jahdali H, Silva RS, Tornes L, Margolesky J, Bennji S, Kim JT, Abdelbary M, Fabi M, Hassan M, Cruz V, El-Shaarawy N, Jaramillo N, Khalil A, Demirkan S, Tekavec-Trkanjec J, Elyaski A, de FreitasRibeiro BN, Kably I, Al-Zeedy K, Jayakrishnan B, Ghirardo S, Barman B, Farber HW, Pankl S, Abou-Zeid A, Young P, Amezyane T, Agarwala MK, Bawaskar P, Hawass M, Saad A, Rasker JJ. A critical analysis of 57 cases of Hughes-Stovin syndrome (HSS). A report by the HSS International Study Group (HSSISG). Int J Cardiol 2021; 331:221-229. [PMID: 33529654 DOI: 10.1016/j.ijcard.2021.01.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 01/09/2021] [Accepted: 01/15/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Hughes-Stovin syndrome (HSS) is a systemic disease characterized by widespread vascular thrombosis and pulmonary vasculitis with serious morbidity and mortality. The HSS International Study Group is a multidisciplinary taskforce aiming to study HSS, in order to generate consensus recommendations regarding diagnosis and treatment. METHODS We included 57 published cases of HSS (43 males) and collected data regarding: clinical presentation, associated complications, hemoptysis severity, laboratory and computed tomography pulmonary angiography (CTPA) findings, treatment modalities and cause of death. RESULTS At initial presentation, DVT was observed in 29(33.3 %), thrombophlebitis in 3(5.3%), hemoptysis in 24(42.1%), and diplopia and seizures in 1 patient each. During the course of disease, DVT occurred in 48(84.2%) patients, and superficial thrombophlebitis was observed in 29(50.9%). Hemoptysis occurred in 53(93.0%) patients and was fatal in 12(21.1%). Pulmonary artery (PA) aneurysms (PAAs) were bilateral in 53(93%) patients. PAA were located within the main PA in 11(19.3%), lobar in 50(87.7%), interlobar in 13(22.8%) and segmental in 42(73.7%). Fatal outcomes were more common in patients with inferior vena cava thrombosis (p = 0.039) and ruptured PAAs (p < 0.001). Death was less common in patients treated with corticosteroids (p < 0.001), cyclophosphamide (p < 0.008), azathioprine (p < 0.008), combined immune modulators (p < 0.001). No patients had uveitis; 6(10.5%) had genital ulcers and 11(19.3%) had oral ulcers. CONCLUSIONS HSS may lead to serious morbidity and mortality if left untreated. PAAs, adherent in-situ thrombosis and aneurysmal wall enhancement are characteristic CTPA signs of HSS pulmonary vasculitis. Combined immune modulators contribute to favorable outcomes.
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Affiliation(s)
- Yasser Emad
- Rheumatology Department, Faculty of Medicine, Cairo University, Kasr Al-Ainy St, 11562 Cairo, Egypt.
| | - Yasser Ragab
- Radiology Department, Faculty of Medicine, Cairo University, Kasr Al-Ainy St, 11562 Cairo, Egypt
| | - Melek Kechida
- Internal Medicine and Endocrinology Department, Fattouma Bourguiba University Hospital, University of Monastir, Rue du 1er juin 1955, Monastir 5019, Tunisia
| | - Aurelien Guffroy
- Service d'immunologie clinique et médecine interne, centre de référence des maladies auto-immunes systémiques rares (RESO), hôpitaux universitaires de Strasbourg, nouvel hôpital civil, 67091 Strasbourg, France; UFR médecine Strasbourg, université de Strasbourg, 67000 Strasbourg, France
| | - Michael Kindermann
- Innere Medizin III (Kardiologie/Angiologie), Universitätskliniken des Saarlandes, Kirrberger Straße, D 66421 Homburg/Saar, Germany
| | - Cal Robinson
- Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5, Canada; Department of Paediatrics, Division of Nephrology, The Hospital for Sick Children, Toronto ON, Canada
| | - Doruk Erkan
- Barbara Volcker Center for Women and Rheumatic Diseases, Hospital for Special Surgery, Weill Cornell Medicine, New York, NY 10021, USA
| | - Faten Frikha
- Department of Internal Medicine, Hedi Chaker Hospital, 3029 Sfax, Tunisia
| | - Ossama Ibrahim
- Morecambe Bay University Hospitals Lancaster, Lancashire, Ashton Rd, Lancaster LA1 4RP, United Kingdom
| | - Hamdan Al-Jahdali
- Pulmonary Division, Department of Medicine, King Saud University for Health Sciences, King Abdulaziz Medical City, Riyadh 11426, Saudi Arabia
| | - Rafael S Silva
- Unidad de Enfermedades Respiratorias, Hospital Regional de Talca, Calle 1 Norte 1990, Talca, Chile
| | - Leticia Tornes
- University of Miami Miller School of Medicine, Department of Neurology, Professional Arts Center, 1150 NW 14th St, Suite 609, Miami, FL 33136, United States
| | - Jason Margolesky
- University of Miami Miller School of Medicine, Department of Neurology, Professional Arts Center, 1150 NW 14th St, Suite 609, Miami, FL 33136, United States
| | - Sami Bennji
- Division of Pulmonology, Department of Medicine, Tygerberg Academic Hospital/Stellenbosch University, Francie van Zijl Drive Tygerberg 7505, Cape Town, South Africa
| | - Jung Tae Kim
- Department of Cardiovascular and Thoracic Surgery, Cheonan Chungmu Hospital, 8 Dagamal 3-gil Seobuk-gu, Cheonan-si, Chungcheongnam-do, Republic of Korea
| | - Mohamed Abdelbary
- Department of Radiology, Badr Hospital, Helwan University, 11790 Cairo, Egypt
| | - Marianna Fabi
- Pediatric Cardiology and Adult Congenital Unit, S. Orsola-Malpighi Hospital, University of Bologna, 40138 Bologna, Italy
| | - Maged Hassan
- Chest Diseases Department, Faculty of Medicine, Alexandria University - Al kartoom square, al Azareta, Alexandria 21526, Egypt
| | - Vitor Cruz
- Serviço de Reumatologia, Hospital das Clínicas, Faculdade de Medicina, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Nashwa El-Shaarawy
- Rheumatology and Rehabilitation Department, Faculty of Medicine, Suez Canal University,Ismailia 4.5 Km the Ring Road, 41522 Ismailia, Egypt
| | - Natalia Jaramillo
- Cardiology Department, Hospital Puerta de Hierro Majadahonda, C/Joaquin Rodrigo 3, Madrid 28222, Spain
| | - Antoine Khalil
- Radiology Department, Bichat-Claude Bernard Hospital, HUPNVS, APHP, Paris University, 46 rue Henri Huchard, 74018 Paris, United States of America
| | - Serkan Demirkan
- Department of Dermatology and Venerology, Izmir Katip Çelebi University Faculty of Medicine, Karabağlar, Izmir, Turkey
| | - Jasna Tekavec-Trkanjec
- Department of Pulmonary medicine, Dubrava University Hospital, Avenija Gojka Šuška 6, 10000 Zagreb, Croatia
| | - Ahmed Elyaski
- Department of prosthesis and orthosis technology Program, Faculty of Applied Health Sciences, Galala University 43511, Suez Governorate, Suez, Egypt
| | - B N de FreitasRibeiro
- Departamento de Radiologia, Instituto Estadual do Cérebro Paulo Niemeyer, R. do Rezende, 156 - Centro, 20231-092 Rio de Janeiro, RJ, Brazil
| | - Issam Kably
- Department of Radiology, Section of Vascular and Interventional Radiology, Jackson Memorial Hospital, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Khalfan Al-Zeedy
- Department of Medicine, Sultan Qaboos University Hospital, 123, Al-Khoud, Muscat, Oman
| | | | - Sergio Ghirardo
- Clinical Department of Medical, Surgical and Health Science, University of Trieste, Piazzale Europa, 1, 34127 Trieste, TS, Italy
| | - Bhupen Barman
- Department of General Medicine, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences (NEIGRIHMS), Mawdiangdiang, Shillong 793018, Meghalaya, India
| | - H W Farber
- Tufts University School of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Boston, MA, United States
| | - Sonia Pankl
- Servicio de Clínica Médica, Hospital Británico de Buenos Aires, Perdriel 74, C1280 AEB Buenos Aires, Argentina
| | - Alaa Abou-Zeid
- Public health Department, Faculty of medicine, Cairo University, Kasr Al-Ainy St, 11562 Cairo, Egypt
| | - Pablo Young
- Servicio de Clínica Médica, Hospital Británico de Buenos Aires, Perdriel 74, C1280 AEB Buenos Aires, Argentina
| | - Taoufik Amezyane
- Department of Internal Medicine, Mohammed V Military Teaching Hospital, Mohammed V-Souissi University, School of Medicine, Rabat, Morocco
| | - Manoj Kumar Agarwala
- Department of Cardiology, Apollo Hospitals, Jubilee Hills, Hyderabad 500096, India
| | - Parag Bawaskar
- Department of Cardiology, Topiwala National Medical College & B.Y.L Nair Charitable Hospital, Dr. A.L. Nair road, Mumbai 400008, Maharashtra, India
| | - Mona Hawass
- Nephrology Department, El Agouza Police Hospital, El Nil St. Agouza, Giza, Governorate, Egypt
| | - Ahmed Saad
- Internal medicine Department, Faculty of Medicine, Cairo University, Kasr Al-Ainy St, 11562 Cairo, Egypt
| | - Johannes J Rasker
- Faculty of Behavioral, Management and Social Sciences, Department Psychology, Health and Technology, University of Twente, Drienerlolaan 5, 7522NB Enschede, the Netherlands
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McLaughlin V, Kim NH, Hemnes AR, Highland KB, Chin KM, Farber HW, Zhao C, Narayan V, Shah M, Chakinala MM. P3671Selexipag dosing and titration in the first 500 patients enrolled in SPHERE (SelexiPag: tHe UsErs dRug rEgistry). Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
SPHERE is an ongoing US-based, multicentre, prospective, registry collecting data on use of the oral selective IP prostacyclin receptor agonist selexipag in real-world settings. Here, we report selexipag dosing and titration in the first 500 patients.
Methods
SPHERE, initiated in November 2016, will enrol 800 patients newly initiated on or already treated with selexipag at enrolment who have a documented titration regimen. Patients are followed for up to 18 months. Patients were considered “newly initiated” on selexipag if they were enrolled in SPHERE ≤60 days after starting selexipag and were considered “previously initiated” if they enrolled >60 days after starting selexipag. The highest dose is the maximum dose reached during up-titration within 6 months since initiation. Selexipag “maintenance dose” is defined as the first dose received for ≥14 days without interruption or change; “titration speed” is defined as the highest dose reached within the first 6 months after initiation divided by the time (in weeks) to reach it.
Results
The data cut-off for this analysis was December 20, 2018. Most patients had Group 1 pulmonary hypertension (PH) (95.4%), which was primarily idiopathic (49.6%) or connective tissue disease associated (26.0%). At selexipag initiation 49.8% of patients had functional class III symptoms. At the time of selexipag initiation, 19.2% of patients were on PH therapy containing a prostacyclin pathway agent (PPA) (8.5% with a parenteral PPA). The median maintenance dose of selexipag was 1200 μg BID (IQR: 800–1600 μg BID) and the median time to reach it was 8.1 wks (IQR: 5.3–11.0 wks). Low (≤400 μg BID), medium (600–1000 μg BID), and high (≥1200 μg BID) maintenance doses were attained by 15.1%, 30.8%, and 49.5% of patients, respectively (and in 23.2%, 31.2%, and 36.2%, respectively, in GRIPHON). The median titration speed was 175 μg BID/wk (IQR: 110.5–195.3 μg BID/wk), slower than the protocol-outlined 200 μg BID/wk in GRIPHON. In SPHERE, most patients titrated at speeds <200 μg BID/wk, regardless of whether they were newly (175 μg BID/wk; IQR 118.6, 195.3) or previously (175 μg BID/wk; IQR 109.8, 195.3) initiated. As expected, more patients discontinued due to adverse events in the newly (29.0%) versus previously (14.1%) initiated groups. The most common adverse events leading to selexipag discontinuation were worsening pulmonary hypertension (2.2%), headache (2.0%), myalgia (1.4%), and nausea (1.0%).
Conclusion
The median maintenance selexipag dose in SPHERE was 1200 μg BID. While the median titration speed was 175 μg BID/wk, there was marked variation and the vast majority of patients titrated slower than 200 μg BID/wk. No new safety signals were observed.
Acknowledgement/Funding
Actelion Pharmaceuticals US, Inc.
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Affiliation(s)
- V McLaughlin
- University of Michigan, Ann Arbor, United States of America
| | - N H Kim
- University of San Diego, La Jolla, United States of America
| | - A R Hemnes
- Vanderbilt University, Nashville, United States of America
| | - K B Highland
- Cleveland Clinic, Cleveland, United States of America
| | - K M Chin
- University of Texas Southwestern Medical School, Dallas, United States of America
| | - H W Farber
- Tufts Medical Center, Boston, United States of America
| | - C Zhao
- Actelion Pharmaceuticals US, Inc., South San Francisco, United States of America
| | - V Narayan
- Actelion Pharmaceuticals US, Inc., South San Francisco, United States of America
| | - M Shah
- Actelion Pharmaceuticals US, Inc., South San Francisco, United States of America
| | - M M Chakinala
- Washington University School of Medicine, St. Louis, United States of America
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Abstract
Primary pulmonary hypertension (PPH) is a rare disorder with an annual incidence of 1 to 2 per million people. The aetiology of this disorder is unknown, but it appears to result from an abnormal interaction of environmental and genetic factors leading to a vasculopathy. The pulmonary arteries in these patients exhibit a spectrum of pathological lesions ranging from the early medial hypertrophy to the end-stage fibrotic plexiform lesions. This characteristic pathology is also observed in pulmonary hypertension resulting from connective tissue disease (particularly systemic sclerosis), HIV infection, portal hypertension and certain toxins. PPH is a condition that is difficult to diagnose and treat, with a median survival of 2.8 years in historical studies. One of the difficulties in treating patients with PHH is that the subacute nature of disease presentation often prevents an accurate diagnosis during the early stages of the illness. Progressive dyspnoea on exertion is the most common presenting symptom. Diagnostic evaluation should include electrocardiography, chest radiograph and echocardiography, and laboratory and other studies to evaluate for secondary causes (e.g. pulmonary function tests, chest computed tomography and ventilation/perfusion scans, pulmonary arteriogram, cardiopulmonary testing, right heart catherisation). PHH is a disorder for which there is no known cure. Current medical and surgical treatment options for patients with PHH include anticoagulation, vasodilators and transplantation. Calcium channel antagonists are currently the oral drugs of choice for the treatment of patients with New York Heart Association (NYHA) Class II disease. These agents, in particular the dihydropyridine compounds, have beneficial effects on haemodynamics and right ventricular function, and possibly increased survival. Epoprostenol is administered by intravenous infusion, and studies have demonstrated short- and long-term improvements in symptoms, haemodynamics and survival. It is well tolerated and has become the treatment of choice for patients with NYHA Class III and IV disease. Inotropic agents are used as a bridge to transplant, which is indicated in patients who do not respond to maximal medical therapy. Experience has shown that single lung, double lung and heart-lung transplantation are approximately of equal efficacy. Currently, single lung transplant appears to be the procedure of choice. Newer agents, such as sildenafil, beraprost and bosentan, are presently being evaluated for the treatment of this disorder. Future study should include elucidation of the pathogenic mechanisms in the development of this vasculopathy, which will hopefully lead to the development of improved treatment options for patients with PHH.
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Affiliation(s)
- E S Klings
- The Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA.
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Klings ES, Christman BW, McClung J, Stucchi AF, McMahon L, Brauer M, Farber HW. Increased F2 isoprostanes in the acute chest syndrome of sickle cell disease as a marker of oxidative stress. Am J Respir Crit Care Med 2001; 164:1248-52. [PMID: 11673218 DOI: 10.1164/ajrccm.164.7.2101020] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Nitric oxide metabolism is altered during the acute chest syndrome of sickle cell disease. In the presence of oxygen and oxygen-related molecules, nitric oxide can preferentially form the powerful oxidants nitrite, nitrate, and peroxynitrite. We hypothesized that increased oxidative stress may contribute to the pathogenesis of acute chest syndrome and measured F2 isoprostanes, a nonenzymatically generated molecule resulting from free radical catalyzed lipid peroxidation in patients with sickle cell disease in various stages of disease. Plasma samples were obtained from nineteen patients with sickle cell disease during acute chest syndrome (pre- and postexchange transfusion), vasoocclusive crisis, and/or at baseline; 12 normal volunteers served as controls. F2 isoprostanes were measured by gas chromatography/mass spectrophotometry. There was a 9-fold increase in F2 isoprostanes in patients with acute chest syndrome as compared with normal volunteers. There was approximately a 50-60% decline in isoprostanes postexchange transfusion to a level similar to that of patients with sickle cell disease at baseline. There was no difference in isoprostanes between vasoocclusive crisis and patients with sickle cell disease at baseline. Increased oxidative stress, measured by generation of F2 isoprostanes, occurs during acute chest syndrome and may have an important role in the pathogenesis of this disease process.
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Affiliation(s)
- E S Klings
- The Pulmonary Center, Department of Surgical Research, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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Klings ES, Farber HW. Role of free radicals in the pathogenesis of acute chest syndrome in sickle cell disease. Respir Res 2001; 2:280-5. [PMID: 11686897 PMCID: PMC59517 DOI: 10.1186/rr70] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2001] [Revised: 03/26/2001] [Accepted: 05/18/2001] [Indexed: 01/29/2023] Open
Abstract
Acute chest syndrome (ACS) of sickle cell disease (SCD) is characterized pathologically by vaso-occlusive processes that result from abnormal interactions between sickle red blood cells (RBCs), white blood cells (WBCs) and/or platelets, and the vascular endothelium. One potential mechanism of vascular damage in ACS is by generation of oxygen-related molecules, such as superoxide (O2-), hydrogen peroxide (H2O2), peroxynitrite (ONOO-), and the hydroxyl (*OH) radical. The present review summarizes the evidence for alterations in oxidant stress during ACS of SCD, and the potential contributions of RBCs, WBCs and the vascular endothelium to this process.
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Affiliation(s)
- E S Klings
- The Pulmonary Center, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA.
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8
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Healy AM, Schwartz JJ, Zhu X, Herrick BE, Varnum B, Farber HW. Gas 6 promotes Axl-mediated survival in pulmonary endothelial cells. Am J Physiol Lung Cell Mol Physiol 2001; 280:L1273-81. [PMID: 11350808 DOI: 10.1152/ajplung.2001.280.6.l1273] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We examined Gas 6-Axl interactions in human pulmonary artery endothelial cells (HPAEC) and in Axl-transduced HPAEC to test Gas 6 function during endothelial cell survival. We identified the 5.0-kb Axl, 4.2-kb Rse, and 2.6-kb Gas 6 mRNAs in HPAEC. Immunoprecipitation and Western blotting confirmed the presence of these proteins. Gas 6 is present in cell-associated and secreted fractions of growth-arrested HPAEC, independent of cell density. In addition, the Axl receptor is constitutively phosphorylated in growth-arrested cultures, and exogenous Gas 6 enhanced Axl phosphorylation threefold. Gas 6 added to growth-arrested HPAEC resulted in a significant increase in cell number (1.5 nM Gas 6 increased cell number 35%). Flow cytometry revealed that Gas 6 treatment resulted in 28% fewer apoptosing cells. Transduction of a full-length Axl cDNA into HPAEC resulted in 54% fewer apoptosing cells after Gas 6 treatment. Collectively, the data demonstrate antiapoptotic activities for Gas 6 in HPAEC and suggest that Gas 6 signaling may be relevant to endothelial cell survival in the quiescent environment of the vessel wall.
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Affiliation(s)
- A M Healy
- Pulmonary Center, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA.
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Farber HW. HIV-associated pulmonary hypertension. AIDS Clin Care 2001; 13:53-5, 59. [PMID: 11710309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Strohmeier GR, Walsh JH, Klings ES, Farber HW, Cruikshank WW, Center DM, Fenton MJ. Lipopolysaccharide binding protein potentiates airway reactivity in a murine model of allergic asthma. J Immunol 2001; 166:2063-70. [PMID: 11160257 DOI: 10.4049/jimmunol.166.3.2063] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The development of allergic asthma is influenced by both genetic and environmental factors. Epidemiologic data often show no clear relationship between the levels of allergen and clinical symptoms. Recent data suggest that bacterial LPS may be a risk factor related to asthma severity. Airborne LPS is typically present at levels that are insufficient to activate alveolar macrophages in the absence of the accessory molecule LPS binding protein (LBP). LBP levels are markedly elevated in bronchoalveolar lavage fluids obtained from asthmatic subjects compared with those in normal controls. We hypothesized that LBP present in the lung could augment the pulmonary inflammation and airway reactivity associated with allergic asthma by sensitizing alveolar macrophages to LPS or other bacterial products and triggering them to release proinflammatory mediators. We compared wild-type (WT) and LBP-deficient mice using a defined Ag immunization and aerosol challenge model of allergic asthma. Immunized LBP-deficient mice did not develop substantial Ag-induced airway reactivity, whereas WT mice developed marked bronchoconstriction following aerosol Ag sensitization and challenge with methacholine. Similarly, production of NO synthase 2 protein and the NO catabolite peroxynitrite was dramatically higher in the lungs of WT mice following challenge compared with that in LBP-deficient mice. Thus, NO production appears to correlate with airway reactivity. In contrast, both mice developed similar pulmonary inflammatory cell infiltrates and elevated mucin production. Thus, LBP appears to participate in the development of Ag-induced airway reactivity and peroxynitrite production, but does not seem to be required for the development of pulmonary inflammation.
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Affiliation(s)
- G R Strohmeier
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
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11
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Abstract
Lipid bodies (LBs), lipid-rich cytoplasmic inclusions found in many cell types, seem to act as nonmembrane sites of eicosanoid formation. Because alterations in eicosanoid products have been demonstrated in endothelial cells (ECs) during hypoxia, we investigated induction of LBs in systemic and pulmonary ECs exposed to acute and/or chronic hypoxia. LBs in ECs were O(2)-concentration dependent, increasing approximately fivefold during acute exposure to 0% O(2) in both cell types. During chronic exposure to 3% O(2), LBs were induced only in systemic ECs. LBs were not induced by other cellular stresses (heat shock or glucose deprivation). Subsequent studies suggested that protein kinase C-dependent and tyrosine kinase-dependent pathways are important in LB induction during hypoxia. PGH synthase was demonstrated in LBs in every case in which they were induced. These are the initial studies to demonstrate induction of LBs in ECs and to demonstrate LB induction during exposure to hypoxia in any cell type. These results imply that in ECs, LBs are structurally distinct inducible sites for synthesis of eicosanoid mediators.
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Affiliation(s)
- L M Scarfo
- Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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12
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Healy AM, Morgenthau L, Zhu X, Farber HW, Cardoso WV. VEGF is deposited in the subepithelial matrix at the leading edge of branching airways and stimulates neovascularization in the murine embryonic lung. Dev Dyn 2000; 219:341-52. [PMID: 11066091 DOI: 10.1002/1097-0177(2000)9999:9999<::aid-dvdy1061>3.0.co;2-m] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
We used whole lung cultures as a model to study blood vessel formation in vitro and to examine the role that epithelial-mesenchymal interactions play during embryonic pulmonary vascular development. Mouse lungs were isolated at embryonic day 11.5 (E11.5) and cultured for up to 4 days prior to blood vessel analysis. Platelet endothelial cell adhesion molecule-1 (PECAM/CD31) and thrombomodulin (TM/CD141) immunolocalization demonstrate that vascular development occurs in lung cultures. The vascular structures identified in lung cultures first appear as a loosely associated plexus of capillary-like structures that with time surround the airways. To investigate the potential role of vascular endothelial cell growth factor (VEGF) during pulmonary neovascularization, we immunolocalized VEGF in embryonic lungs. Our data demonstrate that VEGF is uniformly present in the airway epithelium and the subepithelial matrix of E11.5 lungs. At later time points, E13.5 and E15.5, VEGF is no longer detected in the proximal airways, but is restricted to the branching tips of airways in the distal lung. RT-PCR analysis reveals that VEGF(164) is the predominant isoform expressed in lung cultures. Grafting heparin-bound VEGF(164) beads onto lung explants locally stimulates a marked neovascular response within 48 hr in culture. Semi-quantitative RT-PCR reveals an 18% increase in PECAM mRNA in VEGF(164)-treated whole lung cultures as compared with untreated cultures. The restricted temporal and spatial expression of VEGF suggests that matrix-associated VEGF links airway branching with blood vessel formation by stimulating neovascularization at the leading edge of branching airways.
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Affiliation(s)
- A M Healy
- The Pulmonary Center, Boston University School of Medicine, Boston Massachusetts 02118, USA.
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Abstract
Although HIV-associated pulmonary hypertension and primary pulmonary hypertension (PPH) are clinically and histologically similar, treatment options for the former are limited. Treatment with calcium channel blockers (CCB), proven to be beneficial in a subset of patients with PPH, has been disappointing in HIV-associated pulmonary hypertension and there are no data examining the effects of long-term epoprostenol in this entity. Six patients with severe HIV-associated pulmonary hypertension were treated with continuous intravenous epoprostenol infusions. Acute infusion of epoprostenol resulted in a significant (p < 0.05) decrease in mean pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) of 16. 4 and 32.7%, respectively, and a significant (p < 0.05) increase in mean cardiac output (CO) of 36.9%. At 1 yr, mean PAP and PVR had decreased by 21.7 and 54.9% (p < 0.05), respectively, and mean CO had increased by 51.4% (p < 0.05) when compared with baseline values. Repeat catheterizations of three patients at 2 yr and one patient at 40 mo demonstrated further improvement or maintenance of hemodynamics. In addition, NYHA functional class improved in all patients. We conclude that epoprostenol infusion is effective in improving hemodynamic and functional status in this cohort of six patients with HIV-associated pulmonary hypertension acutely and long-term.
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Affiliation(s)
- R V Aguilar
- The Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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15
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Klings ES, Farber HW. IV epoprostenol for systemic sclerosis. Chest 2000; 118:881-2. [PMID: 10988225 DOI: 10.1378/chest.118.3.881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Eberhardt RT, Forgione MA, Cap A, Leopold JA, Rudd MA, Trolliet M, Heydrick S, Stark R, Klings ES, Moldovan NI, Yaghoubi M, Goldschmidt-Clermont PJ, Farber HW, Cohen R, Loscalzo J. Endothelial dysfunction in a murine model of mild hyperhomocyst(e)inemia. J Clin Invest 2000; 106:483-91. [PMID: 10953023 PMCID: PMC380245 DOI: 10.1172/jci8342] [Citation(s) in RCA: 321] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Homocysteine is a risk factor for the development of atherosclerosis and its thrombotic complications. We have employed an animal model to explore the hypothesis that an increase in reactive oxygen species and a subsequent loss of nitric oxide bioactivity contribute to endothelial dysfunction in mild hyperhomocysteinemia. We examined endothelial function and in vivo oxidant burden in mice heterozygous for a deletion in the cystathionine beta-synthase (CBS) gene, by studying isolated, precontracted aortic rings and mesenteric arterioles in situ. CBS(-/+) mice demonstrated impaired acetylcholine-induced aortic relaxation and a paradoxical vasoconstriction of mesenteric microvessels in response to superfusion of methacholine and bradykinin. Cyclic GMP accumulation following acetylcholine treatment was also impaired in isolated aortic segments from CBS(-/+) mice, but aortic relaxation and mesenteric arteriolar dilation in response to sodium nitroprusside were similar to wild-type. Plasma levels of 8-epi-PGF(2alpha) (8-IP) were somewhat increased in CBS(-/+) mice, but liver levels of 8-IP and phospholipid hydroperoxides, another marker of oxidative stress, were normal. Aortic tissue from CBS(-/+) mice also demonstrated greater superoxide production and greater immunostaining for 3-nitrotyrosine, particularly on the endothelial surface. Importantly, endothelial dysfunction appears early in CBS(-/+) mice in the absence of structural arterial abnormalities. Hence, mild hyperhomocysteinemia due to reduced CBS expression impairs endothelium-dependent vasodilation, likely due to impaired nitric oxide bioactivity, and increased oxidative stress apparently contributes to inactivating nitric oxide in chronic, mild hyperhomocysteinemia.
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Affiliation(s)
- R T Eberhardt
- Evans Department of Medicine, Whitaker Cardiovascular Institute, and. Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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17
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18
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Abstract
Heme oxygenase-1 (HO-1) catalyzes the rate-limiting step in heme catabolism and presumably is involved in cellular iron homeostasis. It is induced by a variety of cellular stresses, including oxygen deprivation and free radical-mediated stress. We examined induction of HO-1 mRNA in skin fibroblasts and investigated the mechanism by which it occurs. Hypoxia did not appear to act via induction of oxygen free radicals: induction of HO-1 was not sensitive to the free radical scavenger GSH or other antioxidants. Moreover, hypoxia did not increase steady-state levels of free radicals generated by fibroblasts. In contrast, HO-1 induction by the oxidants, H(2)O(2) and carbonyl cyanide m-chlorophenylhydrazone (CCCP) was significantly attenuated in the presence of free radical scavengers. This correlated with increased levels of free radical production in fibroblasts treated with these oxidants. Iron depletion by desferrioxamine mesylate, a specific iron complexon, completely inhibited hypoxic stimulation of HO-1 but did not attenuate the effect of H(2)O(2) and CCCP on HO-1 mRNA. Addition of Fe(2+), Fe(3+), or holo-transferrin to fibroblasts increased levels of HO-1 mRNA. Treatment of cells with hypoxia, but not H(2)O(2) or an exogenous source of iron, significantly increased the half-life of HO-1 mRNA. The data suggest hypoxia regulates HO-1 gene expression by a specific posttranscriptional mechanism: stabilization of mRNA. Hypoxia has previously been shown to increase fibroblast collagen synthesis and is thought to play a role in pathogenesis of systemic sclerosis (SSc). Skin fibroblasts isolated from patients with SSc demonstrated significantly stronger induction of HO-1 by hypoxia than did fibroblasts from normal controls. We hypothesize that exposure of SSc fibroblasts to hypoxic conditions leads to in vivo selective proliferation of cells that adapt to hypoxia.
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Affiliation(s)
- M V Panchenko
- Arthritis Center and Section of Rheumatology, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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19
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Klings ES, Hill NS, Ieong MH, Simms RW, Korn JH, Farber HW. Systemic sclerosis-associated pulmonary hypertension: short- and long-term effects of epoprostenol (prostacyclin). Arthritis Rheum 1999; 42:2638-45. [PMID: 10616012 DOI: 10.1002/1529-0131(199912)42:12<2638::aid-anr20>3.0.co;2-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To evaluate the short- and long-term effects of intravenous epoprostenol in patients with pulmonary hypertension (PH) associated with systemic sclerosis (SSc). METHODS Sixteen patients with SSc-associated PH and New York Heart Association (NYHA) class III or IV symptomatology underwent right heart catheterization for determination of baseline hemodynamic values. Vasoreactivity was assessed with either inhaled nitric oxide or intravenous adenosine. After a medication washout period, all patients received intravenous epoprostenol in incrementally increasing doses; tolerance was assessed according to symptoms and hemodynamic findings at each dose increment and at the conclusion of the medication trial. Once a stable medication regimen was established, patients were discharged and followed up as outpatients for assessment of symptoms and exercise tolerance as measured by change in the NYHA class. Repeat hemodynamic testing was performed in 4 patients at 1 year and in 2 patients at 2 years of treatment. RESULTS Therapeutic response to epoprostenol, defined by a reduction in the pulmonary vascular resistance of > or =25%, was achieved in the short-term treatment period in 13 of 16 patients (81.3%). Improvement in symptoms and exercise tolerance occurred in all patients, and a significant short-term hemodynamic response was observed. Followup hemodynamic tests revealed persistent favorable responses in all 4 of the patients studied. CONCLUSION Most patients with PH secondary to SSc manifest favorable hemodynamic responses to epoprostenol in the short term. Long-term epoprostenol was generally well tolerated and provides a potential therapeutic option for patients with PH secondary to SSc.
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Affiliation(s)
- E S Klings
- The Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA
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20
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Abstract
Pulmonary hypertensive states are associated with an increased propensity for thrombosis. This prothrombotic state appears to be a result of pulmonary hypertension promoting endothelial dysfunction and altered hemodynamic status. In some patients with primary pulmonary hypertension, however, a primary prothrombotic state directly induces the pulmonary hypertensive state. This review focuses on the evidence for the association between prothrombotic states, especially increased platelet activation, and the development of pulmonary hypertension.
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Affiliation(s)
- H W Farber
- Whitaker Cardiovascular Institute, Pulmonary Center, Boston University School of Medicine, MA 02118, USA
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21
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Graven KK, Yu Q, Pan D, Roncarati JS, Farber HW. Identification of an oxygen responsive enhancer element in the glyceraldehyde-3-phosphate dehydrogenase gene. Biochim Biophys Acta 1999; 1447:208-18. [PMID: 10542317 DOI: 10.1016/s0167-4781(99)00118-9] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is induced by hypoxia in endothelial cells (EC). Upregulation occurs primarily at the level of transcription and occurs to a much greater extent in EC than in other cell types. To characterize EC specific hypoxia response elements within the GAPDH gene, we performed transient transfection studies in EC, fibroblasts and smooth muscle cells using portions of the GAPDH promoter linked to a CAT reporter gene. These initial studies identified an EC specific hypoxia responsive region that was further characterized (using SV40-promoter-CAT reporter constructs) as a 19-nucleotide sequence (-130 to -112) containing both an hypoxia inducible factor-1 (HIF-1)-binding site and a novel flanking sequence. Electrophoretic mobility shift assays confirmed inducible EC protein binding to this fragment. Mutation of either the HIF-1-binding site or the flanking sequence resulted in complete loss of function and loss of inducible protein binding. Thus, a single HIF-1-binding site is necessary, but not sufficient, for hypoxic regulation of GAPDH in EC. Furthermore, the novel HIF-1 flanking sequence required for GAPDH upregulation and the protein(s) that bind to it may be EC specific.
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Affiliation(s)
- K K Graven
- The Pulmonary Center, Boston University School of Medicine, 715 Albany Street, R-304, Boston, MA 02118, USA.
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22
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Hammerman SI, Klings ES, Hendra KP, Upchurch GR, Rishikof DC, Loscalzo J, Farber HW. Endothelial cell nitric oxide production in acute chest syndrome. Am J Physiol 1999; 277:H1579-92. [PMID: 10516198 DOI: 10.1152/ajpheart.1999.277.4.h1579] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acute chest syndrome (ACS) is the most common form of acute pulmonary disease associated with sickle cell disease. To investigate the possibility that alterations in endothelial cell (EC) production and metabolism of nitric oxide (NO) products might be contributory, we measured NO products from cultured pulmonary EC exposed to red blood cells and/or plasma from sickle cell patients during crisis. Exposure to plasma from patients with ACS caused a 5- to 10-fold increase in S-nitrosothiol (RSNO) and a 7- to 14-fold increase in total nitrogen oxide (NO(x)) production by both pulmonary arterial and microvascular EC. Increases occurred within 2 h of exposure to plasma in a concentration-dependent manner and were associated with increases in endothelial nitric oxide synthase (eNOS) protein and eNOS enzymatic activity, but not with changes in nitric oxide synthase (NOS) III or NOS II transcripts, inducible NOS (iNOS) protein nor iNOS enzymatic activity. RSNO and NO(x) increased whether plasma was obtained from patients with ACS or other forms of vasoocclusive crisis. Furthermore, an oxidative state occurred and oxidative metabolites of NO, particularly peroxynitrite, were produced. These findings suggest that altered NO production and metabolism to damaging oxidative molecules contribute to the pathogenesis of ACS.
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Affiliation(s)
- S I Hammerman
- Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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23
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Keaveny AP, Karasik MS, Farber HW. Successful treatment of chylous ascites secondary to Mycobacterium avium complex in a patient with the acquired immune deficiency syndrome. Am J Gastroenterol 1999; 94:1689-90. [PMID: 10364047 DOI: 10.1111/j.1572-0241.1999.01165.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chylous ascites is a rare form of ascites, the presence of which generally denotes a very poor long term prognosis. We report the case of a patient with acquired immune deficiency syndrome (AIDS) and massive chylous ascites secondary to Mycobacterium avium complex (MAC) infection, identified in the ascitic fluid by a DNA probe assay. With multidrug anti-MAC therapy the ascites resolved completely, and the patient has survived for >21 months. Diagnosis and treatment of MAC-related chylous ascites are reviewed.
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Affiliation(s)
- A P Keaveny
- Department of Medicine, Boston Medical Center and Boston University School of Medicine, Massachusetts 02118, USA
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24
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Farber HW, Graven KK, Kokolski G, Korn JH. Pulmonary edema during acute infusion of epoprostenol in a patient with pulmonary hypertension and limited scleroderma. J Rheumatol 1999; 26:1195-6. [PMID: 10332990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Epoprostenol (prostacyclin) is currently approved for treatment of primary pulmonary hypertension; however, it is being evaluated in other forms of pulmonary hypertension, particularly scleroderma. Side effects associated with this medication are usually minor; serious complications are most often due to the delivery system required for continuous infusion. We describe a life threatening side effect of acute epoprostenol infusion (pulmonary edema) in a patient with pulmonary hypertension associated with limited scleroderma and discuss its management and potential etiology. This is the first case where epoprostenol has been successfully reinstituted.
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Affiliation(s)
- H W Farber
- Pulmonary Center, Boston University School of Medicine, MA 02118, USA.
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25
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Abstract
The vascular endothelium is an important mediator of vascular tone, inflammatory-immune reactions, vascular permeability, angiogenesis, and hemostasis. Endothelial functions may be altered by changes in the local cellular environment, particularly changes in oxygen tension. The mechanisms by which endothelial cells (ECs) respond and adapt to hypoxia are unknown; however, the EC is one of the more hypoxia-tolerant mammalian cell types. Cultured ECs exposed to hypoxia up-regulate a set of stress proteins, termed hypoxia-associated proteins (HAPs), that are distinct from the classically described stress proteins induced by heat shock (heat-shock proteins, HSPs) or glucose deprivation (glucose-regulated proteins, GRPs). Two of these proteins have been identified as the glycolytic enzymes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and non-neuronal enolase (NNE). GAPDH expression during hypoxia is regulated primarily at the level of transcription, while the mechanism of NNE mRNA accumulation remains unclear. GAPDH, NNE, and the other HAPs are up-regulated by transitional metals and deferoxamine; however, unlike the situation with other hypoxia-regulated proteins such as erythropoietin, the up-regulation of GAPDH, NNE, and the other HAPs by hypoxia is not inhibited by carbon monoxide. Subcellular fractionation of hypoxic EC has shown that GAPDH and NNE are up-regulated in the cytoplasmic fraction as would be expected for a glycolytic enzyme; however, a protein corresponding to GAPDH is also up-regulated in the nuclear fraction. This suggests that GAPDH and perhaps NNE have functions aside from their catalytic function in glycolysis. It is unknown whether the up-regulation of GAPDH, NNE, and the other HAPs in ECs is related to the relative ability of ECs to adapt to hypoxia; however, other more-hypoxia-sensitive cells do not up-regulate HAPs.
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Affiliation(s)
- K K Graven
- The Pulmonary Center, Boston University School of Medicine, Massachusetts, USA
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26
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Affiliation(s)
- H W Farber
- Pulmonary Center, Boston University School of Medicine, USA
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27
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Tucci M, Nygard K, Tanswell BV, Farber HW, Hill DJ, Han VK. Modulation of insulin-like growth factor (IGF) and IGF binding protein biosynthesis by hypoxia in cultured vascular endothelial cells. J Endocrinol 1998; 157:13-24. [PMID: 9614353 DOI: 10.1677/joe.0.1570013] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Endothelial cells (EC) are hypoxia-tolerant and their capacity to proliferate in low oxygen tension is essential to maintain vascular endothelium integrity. The present study addresses whether hypoxia alters the expression of insulin-like growth factor (IGF) and IGF binding protein (IGFBP) genes in bovine aortic EC (BAEC) and bovine pulmonary artery EC (BPAEC). EC were cultured in normoxic (21%) conditions and exposed to 0% oxygen for 24, 48, or 72 h; some cells were reoxygenated by exposure to 21% oxygen for 24 or 48 h following hypoxia. IGF-I peptide and mRNA levels were very low in both cell types, and decreased further with exposure to hypoxia. Ligand blotting showed that both cell types synthesized 24 kDa (IGFBP-4), 30 kDa (IGFBP-5 and/or IGFBP-6), 43 kDa and 48 kDa IGFBPs (IGFBP-3 glycosylation variants). IGFBP-4 was the predominant IGFBP expressed by both cell types and did not change with exposure to hypoxia. Hypoxia caused a significant increase in IGFBP-3 secretion in BPAEC but not in BAEC. IGFBP-3 stable mRNA levels in BPAEC were increased correspondingly. IGFBP-5 was expressed only in BAEC and decreased with exposure to hypoxia. IGFBP-6 mRNA expression was low and increased in both cell types with exposure to hypoxia. These results demonstrate that EC IGFBP baseline expression as well as its expression in hypoxia vary in different vascular beds and suggest that the IGFBPs may be the dominant paracrine regulators of proliferation of EC as well as maintenance of endothelium integrity during hypoxia.
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Affiliation(s)
- M Tucci
- Department of Paediatrics, Obstetrics and Gynaecology, Biochemistry and Anatomy, Lawson Research Institute, University of Western Ontario, London, Canada
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Abstract
The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is induced by hypoxia in endothelial cells (EC). To define the mechanisms by which GAPDH is regulated by hypoxia, EC were exposed to cobalt, other transition metals, carbon monoxide (CO), deferoxamine, or cycloheximide in the presence or absence of hypoxia for 24 h, and GAPDH protein and mRNA levels were measured. GAPDH was induced in cells by the transition metals cobalt, nickel, and manganese and by deferoxamine, and GAPDH mRNA induction by hypoxia was blocked by cycloheximide. GAPDH induction by hypoxia, unlike that of other hypoxia-regulated genes, was not inhibited by CO or by 4,6-dioxoheptanoic acid, an inhibitor of heme synthesis. GAPDH induction was not altered by mediators of protein phosphorylation, a calcium channel blocker, a calcium ionophore, or alterations in redox state. GAPDH induction by hypoxia or transitional metals was partially blocked by sodium nitroprusside but was not altered by the inhibitor of nitric oxide synthase N omega-nitro-L-arginine. These findings suggest that GAPDH induction by hypoxia in EC occurs via mechanisms other than those involved in other hypoxia-responsive systems.
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Affiliation(s)
- K K Graven
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA
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29
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Abstract
Hypercarbia is a common complication of respiratory failure, and the technique of "permissive hypercapnia" is used to ventilate individuals with increased peak airway pressures on mechanical ventilators, resulting in elevated arterial PCO2. We studied the effects of hypercarbia on cultured bovine aortic and main pulmonary artery endothelial cell surface proteins, assessing cell surface iodination using lactoperoxidase bound to latex microspheres. We found that 4 h of exposure to 10% CO2 increased the display of substances of apparent molecular masses of 27, 47, and 52 kDa. This effect was not mimicked by acidotic media. Western blots of detergent extracts of main pulmonary artery endothelial cell monolayers did not show increased expression of carbonic anhydrase IV (molecular mass = 52 kDa) after incubation under hypercarbic conditions. Hypercarbia did not change the pattern of [35S]methionine incorporation into endothelial cell proteins. We conclude that hypercarbia of 4-h duration changes iodinated endothelial cell surface proteins. We speculate that this effect may be related to changes in secretion or display of apical cell membrane-associated proteins.
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Affiliation(s)
- S Rounds
- Pulmonary and Critical Care Section, Providence Veterans Affairs Medical Center, Rhode Island 02908, USA
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Hammerman SI, Kourembanas S, Conca TJ, Tucci M, Brauer M, Farber HW. Endothelin-1 production during the acute chest syndrome in sickle cell disease. Am J Respir Crit Care Med 1997; 156:280-5. [PMID: 9230761 DOI: 10.1164/ajrccm.156.1.9611085] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
To investigate the role of the endothelial-derived vasoactive mediator endothelin (ET-1) in the acute chest syndrome (ACS), we incubated bovine pulmonary artery endothelial cells (BPAEC) with red blood cells (equivalent to a hematocrit of 20%) and/or autologous plasma (1:10 dilution) from two patients during ACS and during routine clinic visits. Cellular RNA was analyzed for ET-1 transcripts by Northern analysis and ET-1 protein levels in BPAEC supernatants and in plasma measured by radioimmunoassay. ET-1 mRNA expression and protein levels increased in BPAEC exposed to plasma obtained during ACS; in contrast, exposure to plasma obtained during routine clinic visits did not alter BPAEC ET-1 mRNA expression or protein levels. Plasma ET-1 level was elevated during ACS, decreased during resolution, and remained slightly elevated during routine clinic visits. Plasma obtained from one patient 4 d prior to hospitalization for vasoocclusive crisis contained the highest ET-1 level and markedly increased BPAEC ET-1 mRNA expression and protein levels. In both patients, BPAEC ET-1 mRNA and protein expression in vitro and plasma ET-1 levels in vivo correlated with stage of disease and occurred in the absence of direct erythrocyte contact in vitro. These observations suggest that ET-1 production contributes to development of ACS.
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Affiliation(s)
- S I Hammerman
- Pulmonary Center, Boston University School of Medicine, MA 02118, USA
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Crimlisk JT, Bernardo J, Blansfield JS, Loughlin M, McGonagle EG, McEachern G, Roeber J, Farber HW. Endotracheal reintubation: a closer look at a preventable condition. CLIN NURSE SPEC 1997; 11:145-50; quiz 151-2. [PMID: 9274152 DOI: 10.1097/00002800-199707000-00003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We designed a prospective study of endotracheal intubations and reintubations in our inner city Level 1 Trauma Center, to determine the frequency and causes of reintubation and evaluate the impact of an educational intervention aimed at minimizing unplanned extubations (UEs). After an initial 3-month phase, efforts were instituted to educate healthcare providers to the causes of reintubation noted. An identical 3-month period was then studied to evaluate the efficacy of the interventions. There were 862 patients, all adults, in the initial phase of the study, with 40 reintubation events in 22 patients; of the 808 in the second phase, there were 16 reintubations in 13 patients. The reintubation rate decreased from 4.4% to 1.9% (p = 0.005). Reintubations after UEs decreased from 14% to 5.2% (rate ratio, 0.374; 95% confidence interval = 0.141, 0.990). Multiple reintubation events decreased from 45% to 18.8% (p = 0.07). Increased provider education and protocol changes were associated with lower reintubation rates.
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32
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Tucci M, Hammerman SI, Furfaro S, Saukonnen JJ, Conca TJ, Farber HW. Distinct effect of hypoxia on endothelial cell proliferation and cycling. Am J Physiol 1997; 272:C1700-8. [PMID: 9176162 DOI: 10.1152/ajpcell.1997.272.5.c1700] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Endothelial cells (EC) occupy a strategic location in the vasculature as a barrier between the intravascular compartment and underlying tissues; as such, they are often exposed to stresses, such as decreases in ambient oxygen, diminished metabolic substrate, or changes in temperature, that could affect their ability to divide and proliferate. The present study characterizes cell counts, cell cycle distribution, and bromodeoxyuridine incorporation in pulmonary artery and aortic EC exposed to acute and/or chronic hypoxia and other cellular stresses. During hypoxia, EC division slows but does not arrest; progression through the G1-to-S transition point and/or progression from S to G2/M is altered with an increased percent of EC in S phase. These changes in EC cell cycle distribution with hypoxia are dependent on the origin of the EC as well as the ambient oxygen concentration; moreover, they are distinct from changes observed with elevated temperature or glucose deprivation. and differ from the quiescent pattern induced by serum deprivation or high-density confluence. These findings demonstrate that hypoxia exerts a distinct effect on the cell cycle distribution and proliferation of EC.
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Affiliation(s)
- M Tucci
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA
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Affiliation(s)
- K K Graven
- Pulmonary Center, Boston University School of Medicine, Massachusetts, USA
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34
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Polesky A, Farber HW, Gottlieb DJ, Park H, Levinson S, O'Connell JJ, McInnis B, Nieves RL, Bernardo J. Rifampin preventive therapy for tuberculosis in Boston's homeless. Am J Respir Crit Care Med 1996; 154:1473-7. [PMID: 8912767 DOI: 10.1164/ajrccm.154.5.8912767] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
An epidemic of isoniazid (INH)- and streptomycin (SM)-resistant tuberculosis began among Boston's homeless population in 1984. Individuals with skin test conversions who agreed to preventive therapy received either INH, rifampin, or a combination of INH and rifampin. A total of 204 individuals with documented tuberculin skin test conversions who did not have active tuberculosis at the time of the clinical evaluation for their positive skin test were eligible for preventive therapy. Data on type and length of preventive therapy were obtained from the Tuberculosis Clinic and the Boston Tuberculosis Registry records at Boston City Hospital. The individuals were followed for development of active tuberculosis. Six of 71 (8.6%) individuals who received no therapy, 3 of 38 (7.9%) in the INH group, and none in the rifampin or rifampin plus INH groups (49 and 37 persons, respectively) developed active tuberculosis. Patients in the rifampin group were significantly less likely to develop tuberculosis than patients in the no therapy group (p = 0.04; odds ratio [OR] = 0.00, 95% confidence interval [CI] = 0.00-0.91). Treatment with any rifampin-containing preventive therapy (rifampin or rifampin plus INH) was effective (p < 0.01 ) in preventing development of active disease. The three INH failures were with organisms that were resistant to INH.
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Affiliation(s)
- A Polesky
- Department of Medicine, Boston University School of Medicine, Massachusetts, USA
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35
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Abstract
The mammalian response to cellular stresses often involves upregulation of certain stress proteins. This response is usually neither cell nor stress specific and sometimes results in cross-protection to other stresses. Endothelial cell (EC) hypoxia-associated proteins (HAP) are a unique set of stress proteins upregulated by exposure to environmental hypoxia. In the present study, the specificity of stress protein upregulation was assessed and any potential cross-protection was evaluated using DNA strand break analysis. EC cultured in 21% or 3% oxygen were exposed to single and combined cellular stresses (0% oxygen, reoxygenation, glucose deprivation, sodium arsenite, heat, or hydrogen peroxide). Although EC can upregulate various stress proteins, the HAP are specifically upregulated only with hypoxia and offer no cross-protection against other cellular stresses. Moreover, induction of other stress proteins does not alter the induction of the HAP or the effects of hypoxia in cultured EC. Thus EC display a unique specificity in regard to the stimulus for upregulation of stress proteins and are distinct from other cell types thus far examined.
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Affiliation(s)
- M Tucci
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA
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36
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Abstract
The hypoxia-associated proteins (HAPs) are five cell-associated stress proteins (M(r) 34, 36, 39, 47, and 57) up-regulated in cultured vascular endothelial cells (EC) exposed to hypoxia. While hypoxic exposure of other cell types induces heat shock and glucose-regulated proteins, EC preferentially up-regulate HAPs. In order to identify the 47-kDa HAP, protein from hypoxic bovine EC lysates was isolated, digested with trypsin, and sequenced. Significant identity was found with enolase, a glycolytic enzyme. Western analyses confirmed that non-neuronal enolase (NNE) is up-regulated in hypoxic EC. Western analysis of subcellular fractions localized NNE primarily to the cytoplasm and confirmed that it was up-regulated 2.3-fold by hypoxia. Interestingly, NNE also appeared in the nuclear fraction of EC but was unchanged by hypoxia. Northern analyses revealed that NNE mRNA hypoxic up-regulation began at 1-2 h, peaked at 18 h, persisted for 48 h, and returned to base line after return to 21% O2 for 24 h. Hypoxia maximally up-regulated NNE mRNA levels 3.4-fold. While hypoxic up-regulation of NNE may have a protective effect by augmenting anaerobic metabolism, we speculate that enolase may contribute to EC hypoxia tolerance through one or more of its nonglycolytic functions.
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Affiliation(s)
- R M Aaronson
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118, USA
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37
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Graven KK, Farber HW. Hypoxia-associated proteins. New Horiz 1995; 3:208-18. [PMID: 7583162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The vascular endothelium is an important mediator of vascular tone, angiogenesis, inflammatory-immune reactions, vascular permeability, and hemostasis. Thus, it plays an important role in the pathogenesis of numerous critical care processes, including septic shock, myocardial infarction, the adult respiratory distress syndrome, and acute tubular necrosis. Endothelial functions may be altered by changes in the local cellular environment, particularly changes in PO2. The ability of endothelial cells (EC) to not only sense, but also to adapt to, acute and chronic changes in PO2 is critical to maintaining endothelial metabolic functions and, in turn, to maintaining homeostasis, particularly in the critical care setting. Recent studies have shown that the EC is one of the more hypoxia-tolerant mammalian cell types; however, the mechanisms by which ECs respond and adapt to hypoxia are unknown. Our laboratory has shown that cultured ECs exposed to hypoxia upregulate a set of stress proteins, termed hypoxia-associated proteins (HAPs), that are distinct from the classically described stress proteins induced by heat shock (heat-shock proteins) or glucose deprivation (glucose-regulated proteins). We have recently identified one of these proteins as the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Further studies have shown that GAPDH expression is regulated by hypoxia, primarily at the transcriptional level. Subcellular fractionation of hypoxic EC has shown that GAPDH is upregulated in the cytoplasmic fraction as would be expected with a glycolytic enzyme; however, a protein corresponding to GAPDH is also upregulated in the nuclear fraction. This suggests that the upregulation of GAPDH in EC during hypoxia is related to the potential nonglycolytic functions of this enzyme. Furthermore, the upregulation of GAPDH and the other HAPs (that have yet to be identified) may be related to the relative hypoxia tolerance of EC.
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Affiliation(s)
- K K Graven
- Pulmonary Center, Boston University School of Medicine, MA, USA
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38
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Farber HW. Long-term resolution of disseminated Mycobacterium avium complex infection in a patient with AIDS. Clin Infect Dis 1995; 20:1067-8. [PMID: 7795056 DOI: 10.1093/clinids/20.4.1067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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39
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Abstract
The ability of cells to tolerate hypoxia is critical to their survival, but varies greatly among different cell types. Despite alterations in many cellular responses during hypoxic exposure, pulmonary arterial endothelial cells (PAEC) retain their viability and cellular integrity. Under similar experimental conditions, other cell types, exemplified by renal tubular epithelial cells, are extremely hypoxia sensitive and are rapidly and irreversibly damaged. To investigate potential mechanisms by which PAEC maintain cellular and functional integrity under these conditions, we compared the turnover of adenine and guanine nucleotides in hypoxia tolerant PAEC and in hypoxia-sensitive renal tubular endothelial cells under various hypoxic conditions. Under several different hypoxic conditions, hypoxia-tolerant PAEC maintained or actually increased ATP levels and the percentage of these nucleotides found in the high energy phosphates, ATP and GTP. In contrast, in hypoxia-sensitive renal tubular endothelial cells, the same high energy phosphates were rapidly depleted. Yet, in both cell types, there were minor alterations in the uptake of the precusor nucleotide and its incorporation into the appropriate purine nucleotide phosphates and marked decreases in ATPase and GTPase activity. This maintenance of high energy phosphates in hypoxic PAEC suggests that there exists tight regulation of ATP and GTP turnover in these cells and that preservation of these nucleotides may contribute to the tolerance of PAEC to acute and chronic hypoxia.
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Affiliation(s)
- A V Tretyakov
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118
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40
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Abstract
PURPOSE To evaluate the diagnostic specificity of thallium and gallium scan mismatch as a sign of mycobacterial infection in immunodeficient patients. MATERIALS AND METHODS Thallium and gallium scans obtained in 56 immunodeficient patients between January 1989 and March 1994 were retrospectively reviewed, with special attention to the final diagnoses in all patients with thallium-gallium scan mismatch compared with those whose scans showed other scintigraphic patterns. RESULTS Fourteen patients had focal gallium uptake, but no thallium uptake, in the mediastinum and hilar nodes (thallium-gallium mismatch). Twelve of the 14 had culture-proved mycobacterial infections; one had cryptococcal infection; and in one, the diagnosis was not established. Thirty-seven of the remaining 42 patients who had different scintigraphic patterns on thallium-gallium scans had other complications of acquired immunodeficiency syndrome such as Kaposi sarcoma, non-Hodgkin lymphoma, and bacterial pneumonia. The diagnosis in five of the 42 patients was not known because follow-up data were incomplete. CONCLUSION The thallium-gallium mismatch pattern in immunodeficient patients is specific for mycobacterial infection.
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Affiliation(s)
- V W Lee
- Department of Radiology, Boston University School of Medicine, Boston City Hospital, Mass
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41
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Crimlisk JT, Paris R, McGonagle EG, Calcutt JA, Farber HW. The closed tracheal suction system: implications for critical care nursing. Dimens Crit Care Nurs 1994; 13:292-300. [PMID: 7729318 DOI: 10.1097/00003465-199411000-00003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The Closed Tracheal Suction System (CTSS) is a multiple-use suction catheter available for suctioning the ventilator dependent patient. While research has been reported on its impact on oxygen desaturation, ventilator function, and nosocomial pneumonia, the practical issues of the technical design of the catheter and its advantage in decreasing exposure of staff to infected respiratory secretions have not been investigated. This study reports the critical care nurses' perceptions in the use of the SteriCath (Concord/Portex) CTSS focusing on hemodynamic stability, effectiveness of suctioning, patient safety and staff personnel exposure.
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42
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Graven KK, Troxler RF, Kornfeld H, Panchenko MV, Farber HW. Regulation of endothelial cell glyceraldehyde-3-phosphate dehydrogenase expression by hypoxia. J Biol Chem 1994; 269:24446-53. [PMID: 7929107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Exposure of endothelial cells (EC) to hypoxia results in the increased expression of a distinct set of proteins with molecular masses of 56, 47, 39, 36, and 34 kDa. Their induction appears to be unique to EC and the stress of decreased oxygen tension. To understand the mechanism(s) and significance of the up-regulation of these proteins we have identified the 36-kDa protein by limited amino-terminal amino acid sequencing. The 21-amino acid sequence from the bovine protein exhibited 90.5% identity with the human sequence of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Northern blot analysis showed that the time course and extent of EC GAPDH mRNA up-regulation correlated with the increase in 36-kDa protein synthesis. Nuclear runoff analysis demonstrated that this increase in GAPDH expression is regulated, in part, at the transcriptional level; however, the increase in the rate of transcription did not account for the entire mRNA accumulation, suggesting that GAPDH, like other hypoxia-regulated proteins, is posttranscriptionally regulated. Subcellular fractionation of hypoxic EC showed up-regulation of the 36-kDa protein in the cytoplasmic fraction and, to a lesser extent, in the nuclear fraction. The up-regulation of GAPDH in EC may be related to their relative hypoxia tolerance. Alternatively, the up-regulation of GAPDH in EC during hypoxia may be related to the potential nonglycolytic functions of this enzyme.
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Affiliation(s)
- K K Graven
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118
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43
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Katz MF, Farber HW, Dodds-Stitt Z, Cruikshank WW, Beer DJ. Serotonin-stimulated aortic endothelial cells secrete a novel T lymphocyte chemotactic and growth factor. J Leukoc Biol 1994; 55:567-73. [PMID: 7514199 DOI: 10.1002/jlb.55.5.567] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Atherosclerotic lesions contain multiple cell types including smooth muscle cells, macrophages, and T lymphocytes. The development of an extralymphatic T lymphocyte focus of inflammation in this condition requires chemoattractant-induced cell migration and growth factor-induced cell activation. In a previous study, we described a novel 13-15-kDa T lymphocyte-specific chemotactic cytokine, endothelial cell-derived lymphocyte chemoattractant activity (ED-LCA), secreted by serotonin-stimulated bovine aortic endothelial cells that is distinct from previously identified endothelial cell-derived interleukins (IL) 1, 6, and 8. Because of the association between T lymphocyte chemotactic and growth factor activity, in the current study we investigated the effect of ED-LCA on T cell growth. We assessed its capacity to induce markers of the passage of T cells from the resting (G0) state into the G1 phase of the cell cycle, such as receptors for IL-2 (IL-2R) and transferrin (TFR) and class II major histocompatibility complex antigens (HLA-DR). Incubation of G0 freshly isolated human T lymphocytes for 48 h with chromatographically resolved, partially purified ED-LCA resulted in a threefold increase in expression of the p55 subunit of IL-2R, a threefold increase in TFR, and a twofold increase in HLA-DR. Passage into the G1 phase of the cell cycle was confirmed by cell cycle analysis employing acridine orange. Evaluation of CD4+ and CD8+ T cell subsets by double-antibody labeling demonstrated that the p55 subunit of IL-2R was induced in both T cell subsets. Although incubation of human T cells with ED-LCA alone did not induce proliferation, addition of exogenous IL-2 to T cells pulsed with ED-LCA for 24 h caused a proliferative response with a stimulation index of 3. By up-regulating functional cell surface receptors for IL-2, ED-LCA is a competence growth factor for T lymphocytes and primes them to respond to IL-2. By virtue of its effect on T cells, as a chemotactic and competence factor, this endothelial cell-derived mitoattractant could participate with other T cell growth factors like IL-2 in the recruitment and amplification of the extralymphatic T cell component of atherosclerosis.
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Affiliation(s)
- M F Katz
- Pulmonary Center, Boston University School of Medicine, Massachusetts
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44
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Katz MF, Beer DJ, Duquette D, Cruikshank WW, Antonov AS, Romanov YA, Smirnov VN, Farber HW. Secretion of a novel T-lymphocyte cytokine possessing both chemotactic and growth factor activity by serotonin-stimulated human aortic endothelial cells. Exp Cell Res 1994; 212:113-9. [PMID: 8174633 DOI: 10.1006/excr.1994.1125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The development of an extralymphatic T-lymphocyte focus of inflammation requires chemoattractant-induced cell migration and growth factor-induced cell proliferation. In a previous study, we identified a novel 13- to 15-kDa T-lymphocyte-specific chemotactic cytokine, endothelial cell-derived lymphocyte chemoattractant activity (ED-LCA), secreted by serotonin-stimulated human aortic endothelial cells. Based on its physicochemical and functional characteristics and antibody inhibition studies, ED-LCA is distinct from previously identified endothelial cell-derived IL-1, IL-6, and IL-8. Because of the association between T-lymphocyte chemotactic and growth factor activity, in the current study, we investigated the effect of ED-LCA on T cell growth by assessing its capacity to induce markers of the passage of T cells from the resting (G0) state into the G1 phase of the cell cycle, such as receptors for IL-2 (IL-2R) and transferrin (TFR), and class II major histocompatibility complex antigens (HLA-DR). Incubation of G0 freshly isolated human T lymphocytes for 48 h with chromatographically resolved, partially purified ED-LCA resulted in a threefold increase in expression of IL-2R, a threefold increase in TFR, and a twofold increase in HLA-DR. Double antibody labeling demonstrated that IL-2R was induced in both CD4+ and CD8+ T cell subsets. Although incubation of human T cells with ED-LCA alone did not induce DNA synthesis, addition of exogenous IL-2 to T cells pulsed with ED-LCA for 24 h caused an increase in DNA synthesis with a stimulation index of 3.5. By up-regulating functional cell surface receptors for IL-2 on T lymphocytes and priming them to respond to exogenous IL-2, ED-LCA is a competence growth factor. By virtue of its effect on T cells, as a chemotactic and competence factor, this endothelial cell-derived mitoattractant could participate with other T-cell growth factors like IL-2 in the generation of an extralymphatic T-lymphocyte inflammatory response.
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Affiliation(s)
- M F Katz
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118
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45
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Tarpy SP, Farber HW. Chronic lung disease: when to prescribe home oxygen. Geriatrics (Basel) 1994; 49:27-8, 31-3. [PMID: 8307386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Long-term oxygen therapy has become increasingly common in the treatment of hypoxemic patients with chronic lung disease. Its main benefit and indication is to prolong survival. Oxygen therapy is also recommended for patients with exercise desaturation or sleep desaturation in the presence of hypoxemic complications. Some patients may experience improvement in pulmonary hemodynamics, exercise duration, work of breathing, sleep, and neurologic function. Once a patient meets the criteria for oxygen prescription, you will need to complete a medical necessity form and choose from one of three types of delivery systems. Your role also includes re-evaluating patients at 1 and 3 months to determine the need for continuing therapy.
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46
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Abstract
Vascular endothelial cells (EC) are one of the initial cells exposed to decreases in blood oxygen tension. Bovine EC respond not only by altering secretion of vasoactive, mitogenic, and thrombogenic substances, but also by developing adaptive mechanisms in order to survive acute and chronic hypoxic exposures. EC exposed to hypoxia in vitro upregulate a unique set of stress proteins of Mr 34, 36, 39, 47, and 56 kD. Previous studies have shown that these proteins are cell associated, upregulated in a time and oxygen-concentration dependent manner, and are distinct from heat shock (HSPs) and glucose-regulated proteins (GRPs). To further characterize these hypoxia-associated proteins (HAPs), we investigated their upregulation in human EC from various vascular beds and compared this to possible HAP upregulation in other cell types. Human aortic, pulmonary artery, and microvascular EC upregulated the same set of proteins in response to hypoxia. In comparison, neither lung fibroblasts, pulmonary artery smooth muscle cells, pulmonary alveolar type II cells, nor renal tubular epithelial cells upregulated proteins of these Mr. Instead, most of these cell types induced synthesis of proteins of Mrs corresponding to either HSPs, GRPs, or both. Further studies demonstrated that exposure of EC to related stresses such as cyanide, 2-deoxyglucose, hydrogen peroxide, dithiothreitol, and glucose deprivation did not cause upregulation of HAPs. Evaluation of cellular damage during hypoxia using phase-contrast microscopy, trypan blue exclusion, chromium release, and adherent cell counts showed that EC survived longer with less damage than any of the above cell types. The induction of HAPs, and the lack of induction of HSPs or GRPs, by EC in response to hypoxia may be related to their unique ability to tolerate hypoxia for prolonged periods.
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Affiliation(s)
- K K Graven
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118
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47
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Weinhouse GL, Belloni PN, Farber HW. Effect of hypoxia on endothelial cell surface glycoprotein expression: modulation of glycoprotein IIIa and other specific surface glycoproteins. Exp Cell Res 1993; 208:465-78. [PMID: 8375475 DOI: 10.1006/excr.1993.1268] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Exposure to hypoxia alters many aspects of endothelial cell metabolism and function; however, changes in surface glycoconjugates under these conditions have not been extensively evaluated. In the current studies, we examined surface glycoproteins of cultured bovine aortic (BAEC) and pulmonary arterial (BPAEC) endothelial cells under standard culture conditions (21% oxygen) and following exposure to hypoxia (0% oxygen) for varying time periods (30 min to 18 h) using a system of biotinylation, lectin binding (concanavalin A, Con A; Griffonia simplicifolia, GSA; Arachis hypogaea, PNA; Ricinus communis, RCA; or Triticum vulgaris, WGA), subsequent strep-avidin binding, and staining. Using these methods, we identified differences in lectin binding between the two cell types cultured in 21% oxygen with all lectins except PNA. With exposure to 0% oxygen, there was no change in lectin binding to most surface glycoproteins. Several surface glycoproteins, including glycoprotein IIIa on both cell types, demonstrated a time-dependent decrease in lectin binding; in addition, there was an increase in lectin binding to a few specific surface glycoproteins on each cell type within 30-60 min of exposure to 0% oxygen. These changes in specific surface glycoproteins were confirmed in both cell types by 125I labeling. Increased lectin binding was observed for Con A binding BAEC glycoproteins at molecular weight (MW) 116, 130, and 205 kDa, GSA binding BAEC glycoproteins at MW 120 and 205 kDa, and RCA binding BPAEC glycoproteins at MW 140 and 205 kDa. Increased binding of WGA or PNA was not observed during exposure to hypoxia. The specificity of lectin binding was further confirmed by competitive inhibition with the appropriate sugar. These studies demonstrate that there are baseline differences between BAEC and BPAEC cell surface glycoproteins and that exposure to hypoxia is associated with little change in lectin binding to most surface glycoproteins. There is, however, increased surface expression of a few glycoproteins that differ depending of the origin of the endothelial cell. Although the mechanism of this increase in lectin binding is not yet clear, subsequent studies suggested that it is due to increased availability of select carbohydrate moieties. The time course of these alterations suggests a possible role in the endothelial cell response to decreases in ambient oxygen tension.
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Affiliation(s)
- G L Weinhouse
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118
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48
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Abstract
We have previously reported alterations in cyclooxygenase metabolism in cultured aortic and pulmonary arterial endothelial cells exposed to acute and chronic hypoxia. These alterations depended on the duration and degree of the hypoxic exposure, on the vascular bed from which the endothelial cells were derived, and possibly on the availability of arachidonic acid secondary to modifications in metabolic substrate, membrane phospholipids, and/or membrane phospholipase activity. To investigate this last point further, we have compared plasma membrane phospholipid distribution and phospholipase activity in cultured aortic and pulmonary arterial endothelial cells exposed to both acute and chronic hypoxia, using two different precursors (acetic acid and arachidonic acid) and three different membrane preparations (cell homogenates, partially purified plasma membranes, and highly purified plasma membranes). We found that exposure to acute and chronic hypoxia has profound and complicated effects on endothelial cell phospholipid composition and phospholipase activity and that these effects depend on the origin of the endothelial cells and the duration of hypoxia. Furthermore, we found that the alterations in endothelial cell phospholipid distribution in response to hypoxia depend on the purity of the plasma membrane preparation and the metabolic precursor used to study phospholipid metabolism. Finally, these studies suggested that alterations in phospholipids during hypoxia occurred to a greater extent in compartments of endothelial cells other than the plasma membranes and that the well-recognized tolerance of endothelial cells to hypoxia may be due, in part, to preservation of the integrity of their plasma membranes during exposure to acute and chronic hypoxia.
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Affiliation(s)
- A V Tretyakov
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02118
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49
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Montecalvo MA, Steger KA, Farber HW, Smith BF, Dennis RC, Fitzpatrick GF, Pollack SD, Korsberg TZ, Birkett DH, Hirsch EF. Nutritional outcome and pneumonia in critical care patients randomized to gastric versus jejunal tube feedings. The Critical Care Research Team. Crit Care Med 1992; 20:1377-87. [PMID: 1395657 DOI: 10.1097/00003246-199210000-00004] [Citation(s) in RCA: 292] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To compare nutritional status, gastric colonization, and rates of nosocomial pneumonia in ICU patients randomized to gastric tube feeding vs. patients fed by an endoscopically placed jejunal tube. DESIGN Randomized, prospective study. SETTING Medical and surgical ICUs at Boston City Hospital; surgical ICU at University Hospital. PATIENTS Of the 38 study patients, 19 were randomized to gastric tube feeding and 19 were randomized to an endoscopically placed jejunal tube. The two groups were similar in age, sex, race, underlying disease, and type of surgery. RESULTS The two patient groups were similar in number of days fed, duration of ICU stay, duration of mechanical ventilation, days of antibiotic therapy, and days with fever. Compared with the gastric group, the jejunal group had more patients with circulatory shock on admission (79% vs. 68.4%), higher admission Acute Physiology Score (24.0 vs. 21.7), and fewer patients with pneumonia at randomization (26.3% vs. 31.6%). The jejunal group received a significantly higher percentage of their daily goal caloric intake (p = .05), and had greater increases in serum prealbumin concentrations (p < .05) than the patients with gastric tube feeding. Although the jejunal tube group had more days of diarrhea (3.3 +/- 6.6 vs. 1.8 +/- 2.9), this difference was not statistically significant. Nosocomial pneumonia was diagnosed clinically in two (10.5%) patients in the gastric tube group and in no patients in the jejunal tube group. CONCLUSIONS Patients fed by jejunal tube received a significantly higher proportion of their daily goal caloric intake, had a significantly greater increase in serum prealbumin concentrations, and had a lower rate of pneumonia than patients fed by continuous gastric tube feeding.
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Affiliation(s)
- M A Montecalvo
- Department of Medicine, Boston University School of Medicine, MA
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50
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Abstract
Newly synthesized heparan sulfates purified from the cell layer of bovine aortic endothelial cells (BAECs) and main pulmonary artery endothelial cells (BPAECs) cultured under either normoxic (21% oxygen) or hypoxic (3% oxygen) conditions were characterized by size, charge, and capacity to bind to antithrombin III. Incorporation of radiolabeled sulfate into cell layer-associated heparan sulfate was reduced by 70% in BAECs and by 45% in BPAECs during exposure to 3% oxygen; degradation of radiolabeled heparan sulfate was not affected by hypoxia. However, the percentage of total radiolabeled heparan sulfate that bound to antithrombin III was increased by 33% for BAECs and by 120% for BPAECs when compared with radiolabeled heparan sulfate synthesized during the 21% oxygen exposure. Both the high- and low-antithrombin III affinity radiolabeled heparan sulfate consisted of two components of different sizes; the low-affinity components (mean sizes, 60 and 40 kd) generated under normoxic conditions were smaller than their respective high-affinity components (mean sizes, 70 and 55 kd) by molecular sieve chromatography. The components of low-antithrombin III affinity heparan sulfate generated during exposure to 3% oxygen were increased in size compared with the corresponding low-affinity components generated during the 21% oxygen exposure for both BPAECs and BAECs. In addition, the amount of the larger high-antithrombin III affinity component was reduced in both cell types exposed to hypoxia. There was no difference in functional heparin-like activity per dish between cells cultured at 3% and 21% oxygen; BAECs had twofold to threefold greater activity per dish than did BPAECs at both levels of oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J B Karlinsky
- Pulmonary Section, VA Medical Center, Boston, MA 02130
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