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Featured researches published by Ventzislav Petkov.


The New England Journal of Medicine | 1999

A Preliminary Study of Long-Term Treatment with Interferon Gamma-1b and Low-Dose Prednisolone in Patients with Idiopathic Pulmonary Fibrosis

Rolf Ziesche; Elisabeth Hofbauer; Karin Wittmann; Ventzislav Petkov; Lutz-Henning Block

BACKGROUND AND METHODS Patients with idiopathic pulmonary fibrosis have progressive scarring of the lung and usually die within four to five years after symptoms develop. Treatment with oral glucocorticoids is often ineffective. We conducted an open, randomized trial of treatment with a combination of interferon gamma-1b, which has antifibrotic properties, and an oral glucocorticoid. We studied 18 patients with idiopathic pulmonary fibrosis who had not had responses to glucocorticoids or other immunosuppressive agents. Nine patients were treated for 12 months with oral prednisolone alone (7.5 mg daily, which could be increased to 25 to 50 mg daily), and nine with a combination of 200 microg of interferon gamma-1b (given three times per week subcutaneously) and 7.5 mg of prednisolone (given once a day). RESULTS All the patients completed the study. Lung function deteriorated in all nine patients in the group given prednisolone alone: total lung capacity decreased from a mean (+/-SD) of 66+/-8 percent of the predicted value at base line to 62+/-6 percent at 12 months. In contrast, in the group receiving interferon gamma-1b plus prednisolone, total lung capacity increased (from 70+/-6 percent of the predicted value at base line to 79+/-12 percent at 12 months, P<0.001 for the difference between the groups). In the group that received interferon gamma-1b plus prednisolone, the partial pressure of arterial oxygen at rest increased from 65+/-9 mm Hg at base line to 76+/-8 mm Hg at 12 months, whereas in the group that received prednisolone alone it decreased from 65+/-6 to 62+/-4 mm Hg (P<0.001 for the difference in the change from baseline values between the two groups); on maximal exertion, the value increased from 55+/-6 to 65+/-8 mm Hg in the group that received combined treatment and decreased from 55+/-6 mm Hg to 52+/-5 mm Hg in the group given prednisolone alone (P<0.001). The side effects of interferon gamma-1b, such as fever, chills, and muscle pain, subsided within the first 9 to 12 weeks. CONCLUSIONS In a preliminary study, 12 months of treatment with interferon gamma-1b plus prednisolone was associated with substantial improvements in the condition of patients with idiopathic pulmonary fibrosis who had had no response to glucocorticoids.


Journal of Clinical Oncology | 2006

Antibiotic Treatment Is Not Effective in Patients Infected With Helicobacter pylori Suffering From Extragastric MALT Lymphoma

Birgit Grünberger; Stefan Wöhrer; Berthold Streubel; Michael Formanek; Ventzislav Petkov; Andreas Puespoek; Michael Haefner; Michael Hejna; Ulrich Jaeger; Andreas Chott; Markus Raderer

PURPOSE Apart from anecdotal reports implicating Helicobacter pylori (HP) in the development of extragastric mucosa associated lymphoid tissue (MALT) lymphoma, no large scale prospective studies have been performed on this topic. PATIENTS AND METHODS A total of 77 patients with extragastric MALT lymphoma were prospectively studied. The presence or absence of HP was tested by histology, urease breath test, and serology. Patients were also tested for hepatitis A, B, and C and autoimmune conditions along with assessment of MALT lymphoma-specific genetic changes. RESULTS Evidence for infection with HP was present in 35 of 77 patients (45%), and three of 75 patients tested (4%) were positive for hepatitis C and one for hepatitis B. All patients with HP-infection underwent eradication, 16 before initiation of further therapy. Apart from one patient with lymphoma involving parotid and colon, who achieved regression of the colonic lesions, none of these 16 patients showed regression of the lymphoma after a median follow-up of 14 months (range, 8 to 48+ months) before initiation of definitive treatment. No correlation between HP-status, localization, stage, autoimmune diseases, and genetic findings was seen. CONCLUSION In our series, HP-eradication was ineffective for treatment of extragastric MALT lymphomas. This finding, along with an infection rate of 45%-as could also be expected in the general Austrian population-suggests that HP does not play a role in the development of these lymphomas. Antibiotic treatment targeting HP should, therefore, be discouraged in patients with extragastric MALT lymphomas.


European Respiratory Journal | 2001

Long-term treatment of pulmonary hypertension with aerosolized iloprost

S. Machherndl; Meinhard Kneussl; H. Baumgartner; B. Schneider; Ventzislav Petkov; P. Schenk; Irene Lang

Pulmonary arterial hypertension (PAH), defined as elevated pulmonary arterial pressure and pulmonary vascular resistance, is an end-point of a variety of conditions. The only therapy that has been shown to improve both quality of life and survival is intravenous prostacyclin (prostaglandin I2 (PGI2), epoprostenol). The effect of long-term aerosolized iloprost (Ilomedin, Schering, Berlin, Germany and Vienna, Austria), a stable prostacyclin analogue and potent vasodilator, on haemodynamics and functional status was investigated in 12 patients with severe pulmonary hypertension. Haemodynamic measurements and vasodilator testing by right heart catheterization were performed prior to and after long-term iloprost inhalation therapy. Haemodynamic improvement or increased exercise tolerance was not observed in any of the patients. After a mean+/-SD treatment period of 10+/-5 months, mean+/-SD pulmonary vascular resistance had increased from 11+/-3 Wood Units (mmHg.L(-1).min) to 13+/-4 Wood Units, with unchanged arterial oxygen saturation (92+/-4%, versus 91+/-4%). Within the study period, three patients went into right heart failure and had to be placed on intravenous epoprostenol. The authors conclude that inhaled iloprost in addition to conventional therapy in the presently recommended dose of 100 microg.day(-1) delivered in 8-10 2 h portions, is not an efficient vasodilator therapy in severe pulmonary hypertension. It remains to be shown whether dose increases and/or combination protocols will be effective, or whether inhalation of iloprost may be safe for selected cases of pulmonary hypertension.


Respiratory Medicine | 2012

Strength training increases maximum working capacity in patients with COPD--randomized clinical trial comparing three training modalities.

Karin Vonbank; Barbara Strasser; Jerzy Mondrzyk; Beatrice A. Marzluf; Bernhard Richter; Stephen Losch; Herbert Nell; Ventzislav Petkov; Paul Haber

BACKGROUND AND OBJECTIVE Skeletal muscle dysfunction contributes to exercise limitation in patients with chronic obstructive pulmonary disease (COPD). Strength training increases muscle strength and muscle mass, but there is an ongoing debate on the additional effect concerning the exercise capacity. The purpose of this study was to compare the effects of three different exercise modalities in patients with COPD including endurance training (ET), progressive strength training (ST) and the combination of strength training and endurance training (CT). DESIGN A prospective randomized trial. METHODS Thirty-six patients with COPD were randomly allocated either to ET, ST, or CT. Muscle strength, cardiopulmonary exercise testing, lung function testing and quality of life were assessed before and after a 12-week training period. RESULTS Exercise capacity (Wmax) increased significantly in all three training groups with increase of peak oxygen uptake (VO2peak) in all three groups, reaching statistical significance in the ET group and the CT group. Muscle strength (leg press, bench press, bench pull) improved in all three training groups, with a higher improvement in the ST (+39.3%, +20.9%, +20.3%) and the CT group (+43.3%, +18.1%, +21.6%) compared to the ET group (+20.4%, +6.4%, +12.1%). CONCLUSIONS Progressive strength training alone increases not only muscle strength and quality of life, but also exercise capacity in patients with COPD, which may have implications in prescription of training modality. CLINICALTRIALS.GOV IDENTIFIER: NCT01091623.


Regulatory Peptides | 2007

Involvement of endothelial NO in the dilator effect of VIP on rat isolated pulmonary artery

Anaid Shahbazian; Ventzislav Petkov; Temenuschka Baykuscheva-Gentscheva; Harald Hoeger; Evelin Painsipp; Peter Holzer; Wilhelm Mosgoeller

The endothelium and its interaction with smooth muscle play a central role in the local control of the pulmonary vasculature, and endothelial dysfunction is thought to contribute to pulmonary hypertension and chronic obstructive pulmonary disease. Vasoactive intestinal peptide (VIP), a 28-amino acid neuropeptide, relaxes the rat pulmonary artery, but there is controversy as to whether or not this action of VIP depends on the endothelium. The aim of this study, therefore, was to investigate the role of the endothelium and nitric oxide (NO), the major endothelium-derived relaxing factor, in the dilator action of VIP on the rat isolated pulmonary artery. Pulmonary artery preparations pre-contracted by the alpha(1)-adrenoceptor agonist L-phenylephrine were relaxed by VIP (0.003-1 microM) and acetylcholine (0.003-10 microM) in a concentration-dependent manner. Mechanical removal of the endothelium reduced the maximal response to VIP by about 50% and practically abolished the response to acetylcholine. Inhibition of NO synthesis by N(omega)-nitro-L-arginine methyl ester (0.5 mM) had a similar effect, abolishing the vasorelaxation caused by acetylcholine and attenuating the vasorelaxation caused by VIP by about 50%. From these data it is concluded that the relaxant action of VIP on the rat isolated pulmonary artery depends in part on the presence of the endothelium and that this part is mediated by endothelial NO.


Transplantation | 2013

Lung Transplantation for Bronchiolitis Obliterans After Allogeneic Hematopoietic Stem Cell Transplantation: A Single-center Experience

Ursula Vogl; Kazuhiro Nagayama; Marija Bojic; Mir Alireza Hoda; Walter Klepetko; Peter Jaksch; Sabine Dekan; Viktoria Siersch; Margit Mitterbauer; Peter Schellongowski; Hildegard Greinix; Ventzislav Petkov; Axel Schulenburg; Peter Kalhs; Werner Rabitsch

Background Bronchiolitis obliterans (BO) is a detrimental late pulmonary complication after allogeneic hematopoietic stem cell transplantation (HCT) associated with chronic graft-versus-host disease (cGvHD). When systemic immunosuppressive treatment fails to improve, severe BO patients should be considered for lung transplantation (LuTX). We present seven patients undergoing LuTX for severe refractory BO after HCT. Methods Seven patients with hematologic malignancies developed severe cGvHD with lung involvement presenting as BO after allogeneic HCT. Evaluation for LuTX was initiated after failure of a median of 4 immunosuppressive regimens. Results Between 1996 and 2012, seven patients with severe refractory BO were evaluated for LuTX. The median time from HCT to diagnosis of chronic lung GvHD was 8.2 months (range, 3.7–16.6). At a median time of 18.1 months (range, 6–120) after diagnosis of BO, six patients received a bilateral sequential LuTX, and one patient received a single LuTX. Six postoperative courses were uneventful; the patient with single LuTX died from septic multiorgan failure. Three LuTX recipients had a mild acute rejection after one to three months after LuTX, and one patient experienced fatal chronic rejection and hemolytic uremic syndrome. At present, three (43%) LuTX recipients remain alive at a median observation time of 26 months (range, 1 month–16 years) after LuTX. The median overall survival from LuTX was 24 months (95% CI, 0.5–78); the median overall survival time after allogeneic HCT is 98 months (95% CI, 46–198). Conclusion This case series illustrates that LuTX is a possible therapeutic option for selected patients with severe treatment-refractory BO.


PLOS ONE | 2013

The Interaction of Endothelin-1 and TGF-β1 Mediates Vascular Cell Remodeling

Christopher Lambers; Michael Roth; Jun Zhong; Christoph Campregher; Petra Binder; Bernhard Burian; Ventzislav Petkov; L H Block

Background Pulmonary arterial hypertension is characterized by increased thickness of pulmonary vessel walls due to both increased proliferation of pulmonary arterial smooth muscle cell (PASMC) and deposition of extracellular matrix. In patients suffering from pulmonary arterial hypertension, endothelin-1 (ET-1) synthesis is up-regulated and may increase PASMC activity and vessel wall remodeling through transforming growth factor beta-1 (TGF-β1) and connective tissue growth factor. Objective To assess the signaling pathway leading to ET-1 induced proliferation and extracellular matrix deposition by human PASMC. Methods PASMC were serum starved for 24 hours before stimulation with either ET-1 and/or TGF-β1. ET-1 was inhibited by Bosentan, ERK1/2 mitogen activated protein kinase (MAPK) was inhibited by U0126 and p38 MAPK was inhibited by SB203580. Results ET-1 increased PASMC proliferation when combined with serum. This effect involved the mitogen activated protein kinases (MAPK) ERK1/2 MAPK and was abrogated by Bosentan which caused a G1- arrest through activation of p27(Kip). Regarding the contribution of extracellular matrix deposition in vessel wall remodeling, TGF-β1 increased the deposition of collagen type-I and fibronectin, which was further increased when ET-1 was added mainly through ERK1/2 MAPK. In contrast, collagen type-IV was not affected by ET-1. Bosentan dose-dependently reduced the stimulatory effect of ET-1 on collagen type-I and fibronectin, but had no effect on TGF-β1. Conclusion and Clinical Relevance ET-1 alone does not induce PASMC proliferation and extracellular matrix deposition. However, ET-1 significantly up-regulates serum induced proliferation and TGF-β1 induced extracellular matrix deposition, specifically of collagen type-I and fibronectin. The synergistic effects of ET-1 on serum and TGF-β1 involve ERK1/2 MAPK and may thus present a novel mode of action in the pathogenesis of pulmonary arterial hypertension.


Wiener Klinische Wochenschrift | 2008

Abnormal pulmonary arterial pressure limits exercise capacity in patients with COPD

Karin Vonbank; Georg Christian Funk; Beatrice A. Marzluf; Bernhard Burian; Rolf Ziesche; Leopold Stiebellehner; Ventzislav Petkov; Paul Haber

ZusammenfassungZIELE: Das Vorliegen einer pulmonalen Hypertension ist häufig bei Patienten mit chronisch obstruktiver Lungenerkrankung (COPD) anzutreffen. Der mittlere pulmonalarterielle Druck (mPAP) ist in Ruhe oft nur gering erhöht, zeigt aber einen pathologischen Anstieg unter Belastung. Das Ziel dieser Studie ist es, die Leistungsfähigkeit und den pulmonalen Gasaustausch bei COPD Patienten mit und ohne pulmonalarterieller Hypertension zu untersuchen. PATIENTEN UND METHODEN: Bei 42 Patienten mit COPD Grad II-IV (28 Männer, 14 Frauen) wurden eine Bodyplethysmographie, eine symptomlimitierte Fahrradergospirometrie sowie eine Rechtsherzkatheteruntersuchung durchgeführt. RESULTATE: 32 von 42 Patienten (76%) zeigten einen erhöhten mPAP in Ruhe (PH mPAP = 26,8 ± 5,9 mmHg), bei 10 Patienten war der mPAP in Ruhe im Normbereich (NPH, mPAP = 16,8 ± 2 mmHg). Es gab keinen signifikanten Unterschied hinsichtlich der lungenfunktionellen Parameter in beiden Gruppen. Die maximale Sauerstoffaufnahme (VO2max) war signifikant niedriger in der PH Gruppe (785 ± 244 ml/min) im Vergleich zur NPH Gruppe (1052 ± 207 ml/min, p = 0,004). Es zeigte sich in der PH Gruppe eine erhöhte Totraumventilation mit signifikant erhöhtem Atemäquivalent für CO2 (VECO2 47,3 ± 10 vs 38,6 ± 3,5, p = 0,025) und signifikant höherem arterio-endtidalen CO2 Partialdruck [p(a-ET)CO2]. Der pulmonalarterielle Widerstand (PVR) in Ruhe zeigte eine negative Korrelation hinsichtlich der VO2max, VE/VCO2 und dem arterio-endtidalen CO2 Partialdruck [p(a-ET)CO2]. ZUSAMMENFASSUNG: Patienten mit COPD und erhöhter pulmonalarterieller Druckwerte in Ruhe zeigen eine Verschlechterung des pulmonalen Gasaustausches unter Belastung, eine Beeinträchtigung der maximalen Sauerstoffaufnahme und somit eine limitierte Leistungsfähigkeit.SummaryOBJECTIVE: Pulmonary hypertension (PH) is common in patients with chronic obstructive pulmonary disease (COPD). Mean pulmonary artery pressure (mPAP) is often only slightly elevated at rest but is increased by exercise. The purpose of this study was to determine whether abnormal pulmonary artery pressure impairs exercise capacity in patients with COPD. PATIENTS AND METHODS: 42 patients with moderate-to-very-severe COPD (28 men, 14 women) underwent symptom-limited incremental cardiopulmonary exercise testing and also right-heart catheterization at rest. Abnormal pulmonary artery pressure was defined as mPAP > 20 mmHg at rest. RESULTS: Resting mPAP was elevated in 32 patients (PH, mPAP = 26.8 ± 5.9 mmHg) and normal in 10 non-hypertensive (NPH) patients (NPH, mPAP = 16.8 ± 2 mmHg). There were no significant differences in lung function between the PH and NPH groups. Maximum oxygen uptake during exercise (VO2max) was significantly lower in PH (785 ± 244 ml/min) than in NPH (1052 ± 207 ml/min, P = 0.004). Dead-space ventilation (Vd/Vt) was greater in PH (P = 0.05) with higher VE/VCO2 (ratio of minute ventilation to carbon dioxide output = 47.3 ± 10 vs 38.6 ± 3.5, P = 0.025) and significantly higher arterial-end-tidal pCO2 difference [p(a-ET)CO2]. Pulmonary vascular resistance measured at rest correlated significantly with VO2max, VE/VCO2 and p(a-ET)CO2. CONCLUSIONS: In patients with COPD, abnormal pulmonary artery pressure impairs gas exchange, decreases maximum oxygen uptake during exercise and impairs exercise capacity.


European Journal of Human Genetics | 2007

Vasoactive intestinal peptide gene alterations in patients with idiopathic pulmonary arterial hypertension

Ines Haberl; Klemens Frei; Reinhard Ramsebner; Daniel Doberer; Ventzislav Petkov; Sulaima Albinni; Irene Lang; Trevor Lucas; Wilhelm Mosgoeller

Pulmonary arterial hypertension is a progressive disease, characterised by increased proliferation of pulmonary artery smooth muscle cells, vasoconstriction and remodelling of the vascular wall leading to right heart failure and death. The idiopathic form is rare (idiopathic arterial primary hypertension (IPAH); formerly PPH, MIM# 178600). Our group correlated a deficiency in vasoactive intestinal peptide (VIP; MIM# 192320) levels in serum and lung tissue with the pathogenesis of IPAH. The aim of this study was to investigate the relevance of genetic alterations in VIP to the development of IPAH. We screened 10 patients (age 4–66 years) for alterations in the coding, the noncoding regions and the enhancer region of the VIP gene by direct sequencing. In eight of 10 patients, we found alterations compared to the wild-type sequence. We detected nine alterations. In the noncoding regions, eight alterations were in the introns 1, 2, 3 and 4 (g.448G>A g.501C>T g.764T>C g.2267A>T g.2390C>T g.3144T>C g.3912A>G g.4857A>G). In the coding regions, a single alteration in the 3′ untranslated region in exon 7 (g.8129T>C) was observed in five patients. It appeared in 46% of the control group. The frequency of this alteration in the coding region of the VIP gene could therefore not be correlated with the appearance of IPAH. Apart from the importance of VIP signalling, genetic and/or environmental modifiers might therefore contribute to the development and perpetuation of the disease.


Peptides | 2010

Vasoactive intestinal peptide (VIP) receptor expression in monocyte-derived macrophages from COPD patients.

Bernhard Burian; Angela Storka; Beatrice A. Marzluf; Yong-Cheng Yen; Christopher Lambers; Bruno Robibaro; Karin Vonbank; Wilhelm Mosgoeller; Ventzislav Petkov

Vasoactive intestinal peptide (VIP) is one of the most abundant molecules found in the respiratory tract. Due to its anti-inflammatory and bronchodilatatory properties, it has been proposed as a novel treatment for chronic obstructive pulmonary disease (COPD). The actions of VIP are mediated via three different G-protein-coupled receptors (VPAC1, VPAC2 and PAC1) which are expressed in the respiratory tract and on immunocompetent cells including macrophages. Alveolar macrophages (AM) are key players in the pathogenesis of COPD and contribute to the severity and progression of the disease. While VPAC1 has been reported to be elevated in subepithelial cells in smokers with chronic bronchitis, little is known about VPAC expression of AM in COPD patients. AM from COPD patients show a strong VPAC1 expression which exceeds VPAC2. A similar receptor expression pattern was also observed in lipopolysaccharide (LPS)-activated monocyte-derived macrophages (MDM) from healthy volunteers and COPD patients. VIP has been shown to down-regulate interleukin 8 (IL-8) secretion significantly in MDM after LPS stimulation. The response to VIP was similar in MDM from COPD patients and healthy volunteers. Our results indicate that VPAC1 up-regulation in macrophages is a common mechanism in response to acute and chronic pro-inflammatory stimuli. Although VPAC1 up-regulation is dominant, both receptor subtypes are necessary for optimal anti-inflammatory signaling. The high VPAC1 expression in AM may reflect the chronic pro-inflammatory environment found in the lung of COPD patients. Treatment with VIP may help to decrease the chronic inflammation in the lung of COPD patients.

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Bernhard Burian

Medical University of Vienna

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Christopher Lambers

Medical University of Vienna

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Karin Vonbank

Medical University of Vienna

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Rolf Ziesche

Medical University of Vienna

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Beatrice A. Marzluf

Medical University of Vienna

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Petra Binder

Medical University of Vienna

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Wilhelm Mosgoeller

Medical University of Vienna

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Irene Lang

Medical University of Vienna

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