B Waeber

University of Lausanne, Lausanne, Vaud, Switzerland

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Publications (364)926.89 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: A central pathogenic mechanism of preeclampsia is believed to be the production by the hypoxic placenta of various mediators which promote inflammation and oxidative stress when released into the maternal circulation. The high mobility group box 1 protein (HMGB1) is a ubiquitous nuclear protein. In conditions of hypoxic cellular stress or necrosis, HMGB1 is released into the extracellular milieu. Extracellular HMGB1 has proinflammatory effects, due to the engagement of various cell membrane receptors, notably the receptor for advanced glycation products (RAGE). In preeclampsia, there is evidence for activation of RAGE, and enhanced amounts of HMGB1 have also been demonstrated in the placenta and amniotic fluid, but not, so far, in maternal blood. We hypothesize therefore that, in preeclampsia, the concentration of HMGB1 is abnormally high in maternal blood. We enrolled 16 women in third trimester pregnancy and suffering from preeclampsia (blood pressure > 140/90mmHg with significant proteinuria), 16 women with normal pregnancies who were matched pairwise with the former for BMI and gestation week, and 16 non pregnant healthy women, matched for age with the other two groups. HMGB1 was assessed in peripheral blood with a commercial ELISA kit. The variance between the three groups was appreciated using an ANOVA analysis. Significance was considered for a probability value of < 0.5. The median [interquartile range] HMGB1 concentrations (in ng/mL) were 2.1 [1.1-3.2] in preeclamptic pregnancies, 1.1 [1.0-1.2] in normal pregnancies (p<0.05 vs preeclamptic group), and 0.6 [0.5-0.8] in non pregnant women (p<0.01 vs both other groups). In third trimester pregnancy, the presence of preeclampsia is associated with an approximately two-fold increase of HMGB1 concentration in maternal peripheral blood. Considering its known proinflammatory effects, HMGB1 could be one mediator responsible for the maternal manifestations of preeclampsia. Copyright © 2012. Published by Elsevier B.V.
    Placenta 09/2014; 35(9). DOI:10.1016/j.placenta.2014.06.370 · 2.71 Impact Factor
  • B Gojanovic · F Feihl · G Gremion · B Waeber ·
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    ABSTRACT: Whole-body vibration (WBV) is a new exercise method, with good acceptance among sedentary subjects. The metabolic response to WBV has not been well documented. 3 groups of male subjects, inactive (SED), endurance (END) and strength trained (SPRINT) underwent a session of side-alternating WBV composed of three 3-min exercises (isometric half-squat, dynamic squat, dynamic squat with added load), and repeated at three frequencies (20, 26 and 32 Hz). VO(2), heart rate and Borg scale were monitored. 27 healthy young subjects (10 SED, 8 SPRINT and 9 END) were included. When expressed in % of their maximal value recorded in a treadmill test, both the peak oxygen consumption (VO2) and heart rate (HR) attained during WBV were greatest in the SED, compared to the other two groups (VO2: 59.3% in SED vs 50.8% in SPRINT and 48.0% in END, p <0.01; HR 82.7% in SED vs 80.4% in PRINT and 72.4% in END, p < 0.05). The heart rate and metabolic response to WBV differs according to fitness level and type, exercise type and vibration frequency. In SED, WBV can elicit sufficient cardiovascular response to benefit overall fitness and thus be a potentially useful modality for the reduction of cardiovascular risk.
    Physiological research / Academia Scientiarum Bohemoslovaca 08/2014; 63(6). · 1.29 Impact Factor
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    ABSTRACT: Background: Inflammatory processes play a key role in the pathophysiology of myocardial infarction (MI). Genetic deletion of toll-like recpetors (TLRs), especially TLR2 and TLR4 have shown protective role in murine models of MI. The role of other TLRs remains unknown. We have previously shown that cardiomyocytes express TLR5 and that the ligand of TLR5, flagellin, activates the NF-kappaB and MAPK pathways in cardiomyocytes. We also have shown that injection of flagellin induces acute systolic dysfunction in vivo in mice. Aim: Determine the role of TLR5 in the development of post-MI inflammation. Methods: A murine model of myocardial infarction was done by a 30 minutes ligation of the left anterior descending coronary artery followed by 2 hours of reperfusion. Infarct size was measured by standard Evans blue/TTC staining. Plasma creatine kinase (CK) was quantified as a read out of myocardial necrosis. Tissue and plasma cytokines (MIP-2, MCP-1, IL-6) were quantified by ELISA. To determine the extent of tissue lipid peroxidation we used malondialdehyde and 4-hydroxynonenal-HIS adduct assays. Tissue protein oxidation was tested by protein carbonyl ELISA kit. Phosphorylation of MAPK was analyzed by western blot. Results: Genetic suppression of TLR5 induced a significant increase of myocardial infarct size and plasma CK, of biochemical markers of myocardial oxidative stress, and cytokine levels in the heart and the plasma after MI. These effects were associated with a marked enhancement of p38 phosphorylation in the heart from TLR5 KO mice. Conclusion: TLR5 protects from acute myocardial injury and reduces local and systemic inflammation during myocardial infarction. The mechanisms may involve reduced p38 signaling, decreased oxidative stress and attenuated cytokine expression. Research supported by the Swiss National Science Foundation, Grant n° 310030_135394/1
    Cardiovascular Research 07/2014; 103(suppl 1):S112. DOI:10.1093/cvr/cvu098.47 · 5.94 Impact Factor
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    ABSTRACT: Background: Inflammation comes out to be a critical biological process in the pathophysiology of myocardial infarction (MI). We hypothesize that this inflammation is triggered by necrotic cardiomyocytes (Cmc) that release a set of endogenous molecules (DAMPs: danger-associated molecular patterns) activating inflammatory responses in cardiac fibroblasts. Aim: Analyze in vitro the immune activation of cardiac fibroblasts exposed to necrotic Cmc conditioned media. Methods: Primary neonatal murine cardiac fibroblasts and Cmc were obtained by digestion of neonatal hearts and differential plating technique allowing a selection for cardiomyocytes and cardiac fibroblasts. Cmc were killed by necrotic stimuli including oxidants (hydrogen peroxide) and mechanic stresses (freeze-thaw). Necrosis was assessed using Hoechst/PI stainings. Fibroblasts were exposed to necrotic Cmc conditioned media and mRNA expression of inflammatory genes was measured by real-time PCR and ELISA. Activation of signaling pathways was analyzed by western blot. We used cardiac cells from Myd88-/-, Trif-/- and Nlrp3-/- animals to evaluate the contribution of TLRs/IL1-R and NLRP3 inflammasome in the sensing of necrotic DAMPs. Results: mRNA expression of chemokines such as MCP-1, MIP-2 and IP-10 were induced in fibroblasts exposed to necrotic Cmc conditioned media. Alternatively, fibroblasts exposed to necrotic fibroblasts conditioned media showed a lower increase in mRNA expression of these chemokines. In addition, in fibroblasts from Myd88-/- mice, response to Cmc conditioned media was fully abrogated whereas no difference was observed in Trif-/- and Nlrp3-/- fibroblasts. Conclusion: Cardiac fibroblasts are able to produce a rapid and specific inflammatory response to necrotic Cmc conditioned media involving the expression of neutrophil and monocyte chemoattractants. The dependence on MyD88 adaptor protein strongly suggests that this response relies on TLR/IL-1R signaling. These results engage cardiac fibroblasts as key players in post-MI inflammatory responses as they are able to sense DAMPs from necrotic Cmc and possibly recruit inflammatory cells. Research supported by the Swiss National Science Foundation, Grant n° 310030_135394/1
    Cardiovascular Research 07/2014; 103(suppl 1):S15. DOI:10.1093/cvr/cvu082.32 · 5.94 Impact Factor
  • B Waeber · F Feihl ·
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    ABSTRACT: A cause and effect relationship between arterial hypertension and decline of cognitive function has long been suspected. In middle-age subjects indeed, an abnormally high blood pressure is a risk factor for the long-term development of dementia. Presently, it seems crucial to treat hypertensive patients in order to better protect them against cognitive decline. However, in the elderly patients the risk of mental deterioration may also be enhanced when diastolic pressure becomes too low, for example below 70 mmHg. Further studies are required to better define the antihypertensive drug regimen and target blood pressure which would be optimal for the prevention of cerebral small vessel disease.
    Revue médicale suisse 01/2013; 9(369):108, 110-1.
  • M Burnier · A Pechère Bertschi · B Waeber ·

    Revue médicale suisse 09/2012; 8(353):1691-2.
  • B Waeber · F Feihl ·
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    ABSTRACT: Thiazide (hydrochlorothiazide,...) and thiazide-like (chlortalidone, indapamide,...) diuretics are widely used to treat hypertensive patients. There is growing evidence that these diuretics are not interchangeable and that it might be preferable to choose a thiazide-like diuretic whenever the use of a diuretic is considered. This is in order to prevent optimally the development of cardiovascular complications and the occurrence of metabolic side effects, in particular diabetes.
    Revue médicale suisse 09/2012; 8(353):1699-701. DOI:10.1016/j.hipert.2012.10.003
  • B Waeber · F Feihl ·
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    ABSTRACT: Treatment-resistant hypertension is still common despite the availability of several types of antihypertensive agents acting by different mechanisms. The existence of refractory hypertension should lead to rule out "white-coat hypertension", poor adherence to prescribed drugs as well as classical causes of secondary hypertension such as renal artery stenosis, primary aldosteronism, pheochromocytoma and renal disease. It is also important to consider the possible existence of obstructive sleep apnea or the regular intake of vasopressive drugs or substances.
    Revue médicale suisse 01/2012; 8(323):28-30.
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    A Pechère-Bertschi · B Waeber · M Burnier ·

    Revue médicale suisse 09/2011; 7(308):1731-2.
  • M Cassat · G Wuerzner · M Burnier · B Waeber ·
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    ABSTRACT: The effects of drugs on new cancer and cancer-related death are a major concern. Recently, a meta-analysis raised the possibility that ARBs might have an adverse impact in this respect. This point of view was highly debated until the publication of two other meta-analyses which did not demonstrate any increased risk of new cancer occurrence as well as of cancer related-death with the use of ARBs in patients with hypertension, heart failure and/or nephropathy. This illustrates that the results of meta-analyses should be interpreted cautiously and critically in order to avoid biased conclusions. Overall the bulk of evidence today indicates that ARBs are not associated with an increased cancer risk.
    Revue médicale suisse 09/2011; 7(308):1757-8, 1760.
  • B Waeber · F Feihl ·
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    ABSTRACT: The production of brain natriuretic peptide (BNP) by ventricular cardiomyocytes is increased in patients with left ventricular hypertrophy (LVH). Increased plasma levels of BNP or of the inactive fragment NP-proBNP are associated with an increased cardiovascular risk. The measurement of plasma concentrations of these peptides may be useful for stratifying the cardiovascular risk of hypertensive patients, particularly if there is no electrocardiographic evidence for LVH.
    Revue médicale suisse 09/2011; 7(308):1748-50.
  • A. Heim · L. Liaudet · B. Waeber · F. Feihl ·

    Journal of Hypertension 06/2011; 29:e526. DOI:10.1097/00004872-201106001-01595 · 4.72 Impact Factor
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    ABSTRACT: Purpose: Recent studies showed that pericardial fat was independently correlated with the development of coronary artery disease (CAD). The mechanism remains unclear. We aimed at assessing a possible relationship between pericardial fat volume and endothelium-dependent coronary vasomotion, a surrogate of future cardiovascular events. Methods: Fifty healthy volunteers without known CAD or cardiovascular risk factors (CRF) were enrolled. They all underwent a dynamic Rb-82 cardiac PET/CT to quantify myocardial blood flow (MBF) at rest, during MBF response to cold pressure test (CPT-MBF) and adenosine stress. Pericardial fat volume (PFV) was measured using a 3D volumetric CT method and common biological CRF (glucose and insulin levels, HOMA-IR, cholesterol, triglyceride, hs-CRP). Relationships between MBF response to CPT, PFV and other CRF were assessed using non-parametric Spearman correlation and multivariate regression analysis of variables with significant correlation on univariate analysis (Stata 11.0). Results: All of the 50 participants had normal MBF response to adenosine (2.7±0.6 mL/min/g; 95%CI: 2.6−2.9) and myocardial flow reserve (2.8±0.8; 95%CI: 2.6−3.0) excluding underlying CAD. Simple regression analysis revealed a significant correlation between absolute CPT-MBF and triglyceride level (rho = −0.32, p = 0.024) fasting blood insulin (rho = −0.43, p = 0.0024), HOMA-IR (rho = −0.39, p = 0.007) and PFV (rho = −0.52, p = 0.0001). MBF response to adenosine was only correlated with PFV (rho = −0.32, p = 0.026). On multivariate regression analysis PFV emerged as the only significant predictor of MBF response to CPT (p = 0.002). Conclusion: PFV is significantly correlated with endothelium-dependent coronary vasomotion. High PF burden might negatively influence MBF response to CPT, as well as to adenosine stress, even in persons with normal hyperemic myocardial perfusion imaging, suggesting a link between PF and future cardiovascular events. While outside-to-inside adipokines secretion through the arterial wall has been described, our results might suggest an effect upon NO-dependent and-independent vasodilatation. Further studies are needed to elucidate this mechanism.
    European Heart Journal Supplements 05/2011; 13:1-3. · 15.80 Impact Factor
  • B. Waeber · G. Wuerzner ·

    Praxis 05/2011; 100(11):629-629. DOI:10.1024/1661-8157/a000602
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    ABSTRACT: During recovery from a maximal or submaximal aerobic exercise, augmentation of central (aortic) systolic pressure by reflected pressure waves is blunted in healthy humans. However, the extent to which reflected pressure waves modify the central pulse in diastole in these conditions remains unknown. We evaluated systolic and diastolic central reflected waves in 11 endurance-trained athletes on recovery from a maximal running test on a treadmill (treadmill-max) and a 4000 m run in field conditions. On both occasions in each subject, the radial pulse was recorded with applanation tonometry in the resting preexercise state and then 5, 15, 25, 35, and 45 min after exercise termination. From the central waveform, as reconstructed by application of a generalized transfer function, we computed a systolic (AIx) and a diastolic index (AId) of pressure augmentation by reflections. At 5 min, both indices were below preexercise. At further time-points, AIx remained low, while AId progressively increased, to overshoot above preexercise at 45 min. The same behavior was observed with both exercise types. Beyond the first few minutes of recovery following either maximal or submaximal aerobic exercise, reflected waves selectively augment the central pressure pulse in diastole, at least in endurance-trained athletes.
    Scandinavian Journal of Medicine and Science in Sports 03/2011; 21(6):e325-33. DOI:10.1111/j.1600-0838.2011.01298.x · 2.90 Impact Factor
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    ABSTRACT: Self-monitoring of blood pressure by patients at home (home blood pressure monitoring (HBPM)) is being increasingly used in many countries and is well accepted by hypertensive patients. Current hypertension guidelines have endorsed the use of HBPM in clinical practice as a useful adjunct to conventional office measurements. Recently, a detailed consensus document on HBPM was published by the European Society of Hypertension Working Group on Blood Pressure Monitoring. However, in daily practice, briefer documents summarizing the essential recommendations are needed. It is also accepted that the successful implementation of clinical guidelines in routine patient care is dependent on their acceptance by involvement of practising physicians. The present document, which provides concise and updated guidelines on the use of HBPM for practising physicians, was therefore prepared by including the comments and feedback of general practitioners.
    Journal of human hypertension 12/2010; 24(12):779-85. DOI:10.1038/jhh.2010.54 · 2.70 Impact Factor
  • B Waeber · A Pechère-Bertschi · M Burnier ·

    Revue médicale suisse 09/2010; 6(262):1691-2.
  • J Frantz · F Feihl · B Waeber ·
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    ABSTRACT: Self-measurement of blood pressure at home is increasingly used in the diagnostic and therapeutic approach of hypertension. This technique allows multiple measurements of blood pressure away from the clinical setting, making it possible to improve the evaluation of cardiovascular risk. Recently new guidelines on the use of self-measured blood pressure have been made available by the European Society of Hypertension, as summarized in the present paper.
    Revue médicale suisse 09/2010; 6(262):1696-9.
  • S Zuercher · R Bonvin · L Reber · P-A Michaud · F Feihl · B Waeber ·
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    ABSTRACT: The mastering of the clinical skills is of utmost importance for the physician. The teaching of the skills is nowadays made easier with the which lists all the skills and their respective level of expected mastering at graduation. In order to do a survey on how good the students are at those skills, a logbook based on this document has been setup at the Faculty of biology and medicine of the University of Lausanne. This has shown that students went through a clear progression of the mastering of the skills during their elective year in internal medicine, surgery/orthopaedics, paediatric, obstetric and gynaecology as well as psychiatry. Such an instrument should in the future help to better guide the learning process of the clinical skills and to do a better follow-up of their progress.
    Praxis 01/2010; 99(2):101-5. DOI:10.1024/1661-8157/a000012
  • A Dabiri Askari · F Feihl · B Waeber ·
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    ABSTRACT: The aim of the present report is to outline, in concise from, the changes in vascular structure which accompany hypertension. Consideration will be given to their potential contribution to hypertensive end organ damage. In so doing, it is important to consider both the macrovascular and microvascular levels, because interactions between them are presently believed to be critically important. The links between hypertension and the pathogenesis of arteriosclerosis fall outside the scope of this short review.
    Revue médicale suisse 09/2009; 5(216):1778-80, 1782.

Publication Stats

6k Citations
926.89 Total Impact Points


  • 1982-2014
    • University of Lausanne
      Lausanne, Vaud, Switzerland
    • Boston University
      • Department of Medicine
      Boston, Massachusetts, United States
    • Beverly Hospital, Boston MA
      Beverly, Massachusetts, United States
  • 1980-2014
    • University Hospital of Lausanne
      • • Division de physiopathologie clinique
      • • Service de neurologie
      • • Service de médecine interne
      Lausanne, Vaud, Switzerland
  • 1996
    • ICPS - Institut Cardiovasculaire Paris Sud
      Île-de-France, France
  • 1995
    • Pennsylvania State University
      • Department of Medicine
      University Park, MD, United States
  • 1988-1995
    • Policlinique Médicale Universitaire Lausanne
      Lausanne, Vaud, Switzerland
  • 1988-1989
    • Centre Hospitalier Universitaire de Montpellier
      • Département de médecine interne
      Montpelhièr, Languedoc-Roussillon, France
  • 1979
    • Boston Medical Center
      Boston, Massachusetts, United States