Dexamethasone induces apoptosis in pulmonary arterial smooth muscle cells

BACKGROUND: Dexamethasone suppressed inflammation and haemodynamic changes in an animal model of pulmonary arterial hypertension (PAH). A major target for dexamethasone actions is NF-κB, which is activated in pulmonary vascular cells and perivascular inflammatory cells in PAH. Reverse remodelling is an important concept in PAH disease therapy, and further to its anti-proliferative effects, we sought to explore whether dexamethasone augments pulmonary arterial smooth muscle cell (PASMC) apoptosis. METHODS: Analysis of apoptosis markers (caspase 3, in-situ DNA fragmentation) and NF-κB (p65 and phospho-IKK-α/β) activation was performed on lung tissue from rats with monocrotaline (MCT)-induced pulmonary hypertension (PH), before and after day 14–28 treatment with dexamethasone (5 mg/kg/day). PASMC were cultured from this rat PH model and from normal human lung following lung cancer surgery. Following stimulation with TNF-α (10 ng/ml), the effects of dexamethasone (10(−8)–10(−6) M) and IKK2 (NF-κB) inhibition (AS602868, 0–3 μM (0-3×10(−6) M) on IL-6 and CXCL8 release and apoptosis was determined by ELISA and by Hoechst staining. NF-κB activation was measured by TransAm assay. RESULTS: Dexamethasone treatment of rats with MCT-induced PH in vivo led to PASMC apoptosis as displayed by increased caspase 3 expression and DNA fragmentation. A similar effect was seen in vitro using TNF-α-simulated human and rat PASMC following both dexamethasone and IKK2 inhibition. Increased apoptosis was associated with a reduction in NF-κB activation and in IL-6 and CXCL8 release from PASMC. CONCLUSIONS: Dexamethasone exerted reverse-remodelling effects by augmenting apoptosis and reversing inflammation in PASMC possibly via inhibition of NF-κB. Future PAH therapies may involve targeting these important inflammatory pathways

Peripheral blood B lymphocytes derived from patients with idiopathic pulmonary arterial hypertension express a different RNA pattern compared with healthy controls: a cross sectional study

BACKGROUND: Idiopathic pulmonary arterial hypertension (IPAH) is a progressive and still incurable disease. Research of IPAH-pathogenesis is complicated by the lack of a direct access to the involved tissue, the human pulmonary vasculature. Various auto-antibodies have been described in the blood of patients with IPAH. The purpose of the present work was therefore to comparatively analyze peripheral blood B lymphocyte RNA expression characteristics in IPAH and healthy controls. METHODS: Patients were diagnosed having IPAH according to WHO (mean pulmonary arterial pressure > or = 25 mmHg, pulmonary capillary occlusion pressure < or = 15 mmHg, absence of another explaining disease). Peripheral blood B-lymphocytes of patients and controls were immediately separated by density gradient centrifugation and magnetic beads for CD19. RNA was thereafter extracted and analyzed by the use of a high sensitivity gene chip (Affymetrix HG-U133-Plus2) able to analyze 47000 transcripts and variants of human genes. The array data were analyzed by two different softwares, and up-and down-regulations were defined as at least 1.3 fold with standard deviations smaller than fold-changes. RESULTS: Highly purified B-cells of 5 patients with IPAH (mean pulmonary artery pressure 51 +/- 13 mmHg) and 5 controls were analyzed. Using the two different analyzing methods we found 225 respectively 128 transcripts which were up-regulated (1.3-30.7 fold) in IPAH compared with healthy controls. Combining both methods, there were 33 overlapping up-regulated transcripts and no down-regulated B-cell transcripts. CONCLUSION: Patients with IPAH have a distinct RNA expression profile of their peripheral blood B-lymphocytes compared to healthy controls with some clearly up-regulated genes. Our finding suggests that in IPAH patients B cells are activated

Long-term therapy of interferon-alpha induced pulmonary arterial hypertension with different PDE-5 inhibitors: a case report

BACKGROUND: Interferon alpha2 is widely used in hepatitis and high-risk melanoma. Interferon-induced pulmonary arterial hypertension as a side effect is rare. CASE PRESENTATION: We describe a melanoma patient who developed severe pulmonary arterial hypertension 30 months after initiation of adjuvant interferon alpha2b therapy. Discontinuation of interferon did not improve pulmonary arterial hypertension. This patient could be treated successfully with phosphodiesterase-5 inhibitor therapy. CONCLUSION: This is only the 5th case of interferon-induced pulmonary arterial hypertension and the first documented case where pulmonary arterial hypertension was not reversible after termination of interferon alpha2 therapy. If interferon alpha2 treated patients develop respiratory symptoms, pulmonary arterial hypertension should be considered in the differential diagnosis. For these patients phosphodiesterase-5 inhibitors, e.g. sildenafil or vardenafil, could be an effective therapeutic approach

Optical Nanoantennas for Multiband Surface-Enhanced Infrared and Raman Spectroscopy

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Bone Marrow-Derived Progenitor Cells Augment Venous Remodeling in a Mouse Dorsal Skinfold Chamber Model

The delivery of bone marrow-derived cells (BMDCs) has been widely used to stimulate angiogenesis and arteriogenesis. We identified a progenitor-enriched subpopulation of BMDCs that is able to augment venular remodeling, a generally unexplored area in microvascular research. Two populations of BMDCs, whole bone marrow (WBM) and Lin−/Sca-1+ progenitor cells, were encapsulated in sodium alginate and delivered to a mouse dorsal skinfold chamber model. Upon observation that encapsulated Sca-1+ progenitor cells enhance venular remodeling, the cells and tissue were analyzed on structural and molecular levels. Venule walls were thickened and contained more nuclei after Sca-1+ progenitor cell delivery. In addition, progenitors expressed mRNA transcript levels of chemokine (C-X-C motif) ligand 2 (CXCL2) and interferon gamma (IFNγ) that are over 5-fold higher compared to WBM. Tissues that received progenitors expressed significantly higher protein levels of vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1), and platelet derived growth factor-BB (PDGF-BB) compared to tissues that received an alginate control construct. Nine days following cell delivery, tissue from progenitor recipients contained 39% more CD45+ leukocytes, suggesting that these cells may enhance venular remodeling through the modulation of the local immune environment. Results show that different BMDC populations elicit different microvascular responses. In this model, Sca-1+ progenitor cell-derived CXCL2 and IFNγ may mediate venule enlargement via modulation of the local inflammatory environment

ERS statement on chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism, either symptomatic or not. The occlusion of proximal pulmonary arteries by fibrotic intravascular material, in combination with a secondary microvasculopathy of vessels <500 mu m, leads to increased pulmonary vascular resistance and progressive right heart failure. The mechanism responsible for the transformation of red clots into fibrotic material remnants has not yet been elucidated. In patients with pulmonary hypertension, the diagnosis is suspected when a ventilation/perfusion lung scan shows mismatched perfusion defects, and confirmed by right heart catheterisation and vascular imaging. Today, in addition to lifelong anticoagulation, treatment modalities include surgery, angioplasty and medical treatment according to the localisation and characteristics of the lesions.This statement outlines a review of the literature and current practice concerning diagnosis and management of CTEPH. It covers the definitions, diagnosis, epidemiology, follow-up after acute pulmonary embolism, pathophysiology, treatment by pulmonary endarterectomy, balloon pulmonary angioplasty, drugs and their combination, rehabilitation and new lines of research in CTEPH.It represents the first collaboration of the European Respiratory Society, the International CTEPH Association and the European Reference Network-Lung in the pulmonary hypertension domain. The statement summarises current knowledge, but does not make formal recommendations for clinical practice.Thrombosis and Hemostasi

Доклад ERS по хронической тромбоэмболической легочной гипертензии

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism, either symptomatic or not. The occlusion of proximal pulmonary arteries by fibrotic intravascular material, in combination with a secondary microvasculopathy of vessels &lt; 500 μm, leads to increased pulmonary vascular resistance and progressive right heart failure. The mechanism responsible for the transformation of red clots into fibrotic material remnants has not yet been elucidated. In patients with pulmonary hypertension, the diagnosis is suspected when a ventilation/ perfusion lung scan shows mismatched perfusion defects, and confirmed by right heart catheterisation and vascular imaging. Today, in addition to lifelong anticoagulation, treatment modalities include surgery, angioplasty and medical treatment according to the localisation and characteristics of the lesions. This statement outlines a review of the literature and current practice concerning diagnosis and management of CTEPH. It covers the definitions, diagnosis, epidemiology, follow-up after acute pulmonary embolism, pathophysiology, treatment by pulmonary endarterectomy, balloon pulmonary angioplasty, drugs and their combination, rehabilitation and new lines of research in CTEPH. It represents the first collaboration of the European Respiratory Society, the International CTEPH Association and the European Reference Network-Lung in the pulmonary hypertension domain. The statement summarises current knowledge, but does not make formal recommendations for clinical practice.Хроническая тромбоэмболическая (ХТЭ) легочная гипертензия (ЛГ) – редкое осложнение острой тромбоэмболии легочной артерии (ТЭЛА) – как симптоматической, так и бессимптомной. При окклюзии проксимальных сегментов легочных артерий фиброзным внутрисосудистым материалом в комбинации со вторичной микроваскулопатией сосудов диаметром &lt; 500 мкм повышаются легочное сосудистое сопротивление и прогрессирующая правожелудочковая недостаточность. Механизм трансформации кровяных сгустков в остаточный фиброзный материал до сих пор не установлен. ХТЭ ЛГ у пациентов с ЛГ подозревается в случае, когда по данным вентиляционно-перфузионной сцинтиграфии легких выявляются несоответствующие картине вентиляции дефекты перфузии, которые подтверждаются при катетеризации правых отделов сердца и визуализации сосудов. В зависимости от локализации и типов повреждений, помимо пожизненного приема антикоагулянтов, на сегодняшний день доступны хирургическое лечение, ангиопластика и медикаментозное лечение. В настоящем докладе представлен обзор литературы и описана современная практика установления диагноза и ведения больных ХТЭ ЛГ. Документ охватывает области определения, диагностики, эпидемиологии, наблюдения после острой ТЭЛА, патофизиологии, лечения с помощью легочной тромбэндартерэктомии, баллонной ангиопластики легочной артерии, лекарственных препаратов и их комбинаций, реабилитации и новых направлений исследований в области ХТЭ ЛГ. Доклад представляет собой результат первого совместного проекта по ЛГ Европейского респираторного общества, Международной ассоциации хронической тромбоэмболической легочной гипертензии и Европейской сети медицинских учреждений по редким заболеваниям легких. В докладе резюмируются текущие знания, но не даются формальные рекомендации для клинической практики

CONCENTRATION DEPENDENT FAR INFRARED-ABSORPTION SPECTRA OF THE MIXTURES FURAN/CS2, FURAN/CCL4, FURAN/C6H6

The far infrared absorption spectra of furan in liquid solutions with carbon disulphide, carbon tetrachloride and benzene, are to the first time presented, along with the absorption spectra of neat furan at three different temperatures. The spectral behaviour of the absorption curves is studied for each solvent at three mole fractions of furan. The results are qualitatively discussed in terms of the intermolecular geometry in the solution, as determined by the structure characteristics of the non-polar solvents, and also in terms of the interaction between solvent and solute, producing under certain circumstances an interaction induced contribution to the permanent dipole moment of the furan molecule