Philippe JEAN-PIERRE

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Michaël MonetV'Yacheslav Lehen'KyiFlorian GackiereVirginie FirlejMatthieu VandenbergheMorad RoudbarakiDimitra GkikaAlbin PourtierGabriel BidauxChristian SlomiannyPhilippe DelcourtFrançois RassendrenJean-Pierre BergeratJocelyn CéralineFlorence CabonSandrine HumezNatalia Prevarskaya
• Organismes : Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Laboratoire Epigenetique et Cancer Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Institut de biologie de Lille - IBL Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Institut de Génomique Fonctionnelle Hôpitaux Universitaires de Strasbourg Physiopathologie et Médecine Translationnelle Laboratoire Epigenetique et Cancer Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate Rôle des canaux ioniques membranaires et du calcium intracellulaire dans la physiopathologie de la prostate
• Publié dans Cancer Research le 29/10/2020

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Résumé : Abstract Castration resistance in prostate cancer (PCa) constitutes an advanced, aggressive disease with poor prognosis, associated with uncontrolled cell proliferation, resistance to apoptosis, and enhanced invasive potential. The molecular mechanisms involved in the transition of PCa to castration resistance are obscure. Here, we report that the nonselective cationic channel transient receptor potential vanilloid 2 (TRPV2) is a distinctive feature of castration-resistant PCa. TRPV2 transcript levels were higher in patients with metastatic cancer (stage M1) compared with primary solid tumors (stages T2a and T2b). Previous studies of the TRPV2 channel indicated that it is primarily involved in cancer cell migration and not in cell growth. Introducing TRPV2 into androgen-dependent LNCaP cells enhanced cell migration along with expression of invasion markers matrix metalloproteinase (MMP) 9 and cathepsin B. Consistent with the likelihood that TRPV2 may affect cancer cell aggressiveness by influencing basal intracellular calcium levels, small interfering RNA–mediated silencing of TRPV2 reduced the growth and invasive properties of PC3 prostate tumors established in nude mice xenografts, and diminished expression of invasive enzymes MMP2, MMP9, and cathepsin B. Our findings establish a role for TRPV2 in PCa progression to the aggressive castration-resistant stage, prompting evaluation of TRPV2 as a potential prognostic marker and therapeutic target in the setting of advanced PCa. Cancer Res; 70(3); 1225–35

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Jean-Marc CampagneFrancine Agbossou-NiedercornTahar AyadOlivier BaudoinGérard BuonoIsabelle ChataignerChristophe CrévisyIsabelle DezMorgan DonnardFabienne FacheChristian FeassonAnnie-Claude GaumontLaurent GiordanoPeter HesemannFrancis MarsaisMarc MauduitVéronique MicheletAndré MortreuxPhannarath PhansavathPiva OlivierJean-Philippe RoblinJacques RoudenMarc TailleferPatrick Y. ToullecThéophile TschamberVirginie Vidal
• Organismes : Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier Unité de Catalyse et Chimie du Solide - UMR 8181 Laboratoire Charles Friedel Institut de Chimie et Biochimie Moléculaires et Supramoléculaires Institut des Sciences Moléculaires de Marseille Institut de Chimie Organique Fine Institut des Sciences Chimiques de Rennes Laboratoire de chimie moléculaire et thioorganique Laboratoire de Chimie organique et bioorganique Institut de Chimie et Biochimie Moléculaires et Supramoléculaires Institut de Chimie Organique Fine Laboratoire de chimie moléculaire et thioorganique Institut des Sciences Moléculaires de Marseille Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier Institut de Chimie Organique Fine Institut des Sciences Chimiques de Rennes Laboratoire Charles Friedel Unité de Catalyse et Chimie du Solide - UMR 8181 Laboratoire Charles Friedel Institut de Chimie et Biochimie Moléculaires et Supramoléculaires Laboratoire de Chimie des Hétérocycles et des Glucides Laboratoire de chimie moléculaire et thioorganique Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier Laboratoire Charles Friedel Laboratoire de Chimie organique et bioorganique Laboratoire Charles Friedel
• Publié dans L'Actualité Chimique le 02/11/2020

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Résumé : The organic synthesis challenge is now to manage the demands for efficiency and selectivity with the development of a "green and sustainable" organic chemistry. The goals are to obtain complex molecular architectures by reducing the environmental impact, by developing atom- and step-economic new methodologies, and by developing smart alternatives to usual organic solvents.

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Julie SarfatiAnne Guiochon-MantelPhilippe RondardIsabelle ArnulfAlfons Garcia-PiñeroSlawomir WolczynskiSylvie Brailly-TabardMaud BidetMaria Ramos-ArroyoMichèle MathieuAnne Lienhardt-RoussieGraeme MorganZinet TurkiCatherine BremontJames LespinasseHélène Du BoullayNathalie Chabbert-BuffetSébastien JacquemontGérard ReachNicole de TalencePaolo TonellaBernard ConradFrancois DespertBruno DelobelThierry BrueClaire BouvattierSylvie CabrolMichel PugeatArnaud MuratPhilippe BouchardJean-Pierre HardelinCatherine DodéJacques Young
• Organismes : Récepteurs stéroïdiens : physiopathologie endocrinienne et métabolique Service de génétique moléculaire, pharmacogénétique et hormonologie Institut de Génomique Fonctionnelle Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière Récepteurs stéroïdiens : physiopathologie endocrinienne et métabolique Service de génétique moléculaire, pharmacogénétique et hormonologie Head of the Department of Medical Genetics Département de Génétique Chromosomique Service de génétique médicale Centre de Génétique Chromosomique [Hôpital Saint Vincent de Paul] Centre de recherche en neurobiologie - neurophysiologie de Marseille Laboratoire Microorganismes : Génome et Environnement Récepteurs stéroïdiens : physiopathologie endocrinienne et métabolique Service d'Endocrinologie et Maladies de la reproduction
• Publié dans Journal of Clinical Endocrinology and Metabolism le 01/11/2020

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Résumé : Context: Both biallelic and monoallelic mutations in PROK2 or PROKR2 have been found in Kallmann syndrome (KS). Objective: The objective of the study was to compare the phenotypes of KS patients harboring monoallelic and biallelic mutations in these genes. Design and Patients: We studied clinical and endocrine features that reflect the functioning of the pituitary-gonadal axis, and the nonreproductive phenotype, in 55 adult KS patients (42 men and 13 women), of whom 41 had monoallelic mutations and 14 biallelic mutations in PROK2 or PROKR2. Results: Biallelic mutations were associated with more frequent cryptorchidism (70% vs. 34%, P < 0.05) and microphallus (90% vs. 28%, P < 0.001) and lower mean testicular volume (1.2 +/- 0.4 vs. 4.5 +/- 6.0 ml; P < 0.01) in male patients. Likewise, the testosterone level as well as the basal FSH level and peak LH level under GnRH-stimulation were lower in males with biallelic mutations (0.2 +/- 0.1 vs. 0.7 +/- 0.8 ng/ml; P = 0.05, 0.3 +/- 0.1 vs. 1.8 +/- 3.0 IU/liter; P < 0.05, and 0.8 +/- 0.8 vs. 5.2 +/- 5.5 IU/liter; P < 0.05, respectively). Nonreproductive, nonolfactory anomalies were rare in both sexes and were never found in patients with biallelic mutations. The mean body mass index of the patients (23.9 +/- 4.2 kg/m(2) in males and 26.3 +/- 6.6 kg/m(2) in females) did not differ significantly from that of gender-, age-, and treatment-matched KS individuals who did not carry a mutation in PROK2 or PROKR2. Finally, circadian cortisol levels evaluated in five patients, including one with biallelic PROKR2 mutations, were normal in all cases. Conclusion: Male patients carrying biallelic mutations in PROK2 or PROKR2 have a less variable and on average a more severe reproductive phenotype than patients carrying monoallelic mutations in these genes. Nonreproductive, nonolfactory clinical anomalies associated with KS seem to be restricted to patients with monoallelic mutations.

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Pierre BigotGiovanni LughezzaniPierre I. KarakiewiczPaul PerrotteNathalie Rioux-LeclercqVeronique Catros-QuemenerFrancoise BouetJean-Philippe MoulinouxBernard CipollaJean-Jacques Patard
• Organismes : Service d'urologie [Rennes] = Urology [Rennes] Service d'urologie Cancer Prognostics and Health Outcome Unit Department of urology Cancer Prognostics and Health Outcome Unit Cancer Prognostics and Health Outcomes Unit Cancer Prognostics and Health Outcomes Unit Institut de Génétique et Développement de Rennes Service d'anatomie et cytologie pathologiques [Rennes] = Anatomy and Cytopathology [Rennes] Service d'anatomie et cytologie pathologiques [Rennes] = Anatomy and Cytopathology [Rennes] Service d'anatomie et cytologie pathologiques [Rennes] = Anatomy and Cytopathology [Rennes] Service d'anatomie et cytologie pathologiques [Rennes] = Anatomy and Cytopathology [Rennes] Centre Hospitalier Privé Saint-Grégoire Service d'urologie [Rennes] = Urology [Rennes]
• Publié dans The Journal of Urology le 27/10/2020

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Résumé : PURPOSE: The polyamines spermine and spermidine are ubiquitous polycationic structures which are essential for cell proliferation and differentiation. Circulating polyamines, spermine and spermidine, represent valuable prognostic markers in prostate cancer, acute leukemia and supratentorial malignant glioma. We tested whether spermine and spermidine could improve the prognostic ability of several established predictors of cancer specific mortality after partial or radical nephrectomy for renal cell carcinoma. MATERIALS AND METHODS: Testing was performed on 399 patients with stages T(1-4), N(0-2), M(0-1) renal cell carcinoma who were treated with radical or partial nephrectomy at a single institution between 1990 and 2007. Univariable and multivariable Cox regression models tested the prognostic ability of spermine and spermidine levels in cancer specific mortality predictions. Covariates consisted of TNM stage, Fuhrman grade, tumor size and symptom classification. Harrell's concordance index (c-index) quantified accuracy and 200 bootstrap resamples were used to correct for overfit bias. RESULTS: The 5-year cancer specific mortality-free survival of patients with spermine levels 3 or less, 3.1 to 8, 8.1 to 13 and greater than 13 nmol/8x10(9) erythrocytes was 88.8%, 75.8%, 40.2% and 21.8%, respectively. Similarly the 5-year cancer specific mortality-free survival of patients with spermidine levels 12 or less, 12.1 to 15, 15.1 to 21 and greater than 21 nmol/8x10(9) erythrocytes was 79.0%, 56.6%, 53.2% and 27.4%, respectively. On multivariable analyses addressing cancer specific mortality after surgery spermine (p = 0.007) and spermidine (p = 0.04) achieved independent predictor status. Consideration of spermine and spermidine also improved the accuracy of established cancer specific mortality predictors by 2.2% (p <0.001). CONCLUSIONS: Spermine and spermidine may significantly improve the prognostic value of established cancer specific mortality predictors after partial or radical nephrectomy for all stages of renal cell carcinoma. Independent external validation of our findings is required.

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Maxime CrépelClaudio JeldresPaul PerrotteUmberto CapitanioHendrik IsbarnShahrokh F. ShariatDaniel LibermanMaxine SunGiovanni LughezzaniPhilippe ArjaneHugues WidmerMarkus GraefenFrancesco MontorsiJean-Jacques PatardPierre I. Karakiewicz
• Organismes : Cancer Prognostics and Health Outcome Unit Service d'urologie [Rennes] = Urology [Rennes] Cancer Prognostics and Health Outcome Unit Cancer Prognostics and Health Outcomes Unit Cancer Prognostics and Health Outcomes Unit Cancer Prognostics and Health Outcome Unit Department of urology Cancer Prognostics and Health Outcome Unit Martini-Clinic Division of Urology Cancer Prognostics and Health Outcome Unit Cancer Prognostics and Health Outcome Unit Cancer Prognostics and Health Outcome Unit Department of urology Cancer Prognostics and Health Outcome Unit Department of urology Cancer Prognostics and Health Outcomes Unit Martini-Clinic Cancer Prognostics and Health Outcomes Unit Service d'urologie [Rennes] = Urology [Rennes] Cancer Prognostics and Health Outcome Unit Cancer Prognostics and Health Outcomes Unit
• Publié dans Urology le 26/10/2020

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Résumé : OBJECTIVES: To test the effect of nephron-sparing surgery (NSS) vs radical nephrectomy (RN) on cancer-specific mortality (CSM) in patients with T1bN0M0 renal cell carcinoma (RCC) in a population-based cohort. To date, only few series from tertiary care centers supported the use of NSS for T1bN0M0 (range 4-7 cm) RCC. METHODS: The Surveillance, Epidemiology, and End Results database allowed us to identify 275 NSS (5.3%) and 4866 RN (94.7%) patients treated for T1bN0M0 RCC between 1988 and 2004. Analyses matched for age, year of surgery, tumor size, and Fuhrman grade addressed the effect of nephrectomy type (NSS vs RN) on CSM. RESULTS: Five years after surgery, the surviving proportions of NSS and RN patients matched for age, tumor size, and year of surgery were respectively 91.4 and 95.3% and 90.1 and 93.8% in the cohort, where additional matching for Fuhrman grade was performed. Neither of the matched analyses resulted in statistically significant CSM difference (P = .1 and .4) between NSS and RN. Similarly, competing-risks regression analyses based on both matching schemes also failed to reveal statistically significant CSM differences (P = .3 and .3). CONCLUSIONS: Our study represents the largest and the only population-based analysis of cancer control efficacy of NSS vs RN in T1bN0M0 RCC. It indicates that NSS does provide equivalent cancer control relative to RN. In consequence, based on cancer control equivalence, NSS should be given equal consideration to RN in patients with T1bN0M0 lesions.

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Laurence GuldnerLuc MultignerFanny HéraudChristine MonfortJean Pierre ThoméArnaud GiustiPhilippe KadhelSylvaine Cordier
• Organismes : Groupe d'Etude de la Reproduction Chez l'Homme et les Mammiferes Département santé environnement Groupe d'Etude de la Reproduction Chez l'Homme et les Mammiferes Direction de l'évaluation des risques nutritionnels et sanitaires Groupe d'Etude de la Reproduction Chez l'Homme et les Mammiferes Laboratory of Animal Ecology and Ecotoxicology Laboratory of Animal Ecology and Ecotoxicology Groupe d'Etude de la Reproduction Chez l'Homme et les Mammiferes Service de gynécologie-obstétrique Groupe d'Etude de la Reproduction Chez l'Homme et les Mammiferes
• Publié dans Environmental Research le 24/10/2020

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Résumé : CONTEXT: Chlordecone, an environmentally persistent organochlorine insecticide used intensively in banana culture in the French West Indies until 1993, has permanently polluted soils and contaminated foodstuffs. Consumption of contaminated food is the main source of exposure nowadays. We sought to identify main contributors to blood chlordecone concentration (BCC) and to validate an exposure indicator based on food intakes. MATERIAL AND METHODS: We used a food frequency questionnaire (FFQ) completed by a sample of 194 pregnant women to estimate their dietary exposure to chlordecone and compared it to blood levels. In a first approach, chlordecone daily intake was estimated as the product of daily eaten quantity of 214 foodstuffs, multiplied by their chlordecone content, and summed over all items. We then predicted individual blood chlordecone concentration with empirical weight regression models based on frequency of food consumption, and without contamination data. RESULTS: Among the 191 subjects who had BCC determination, 146 (76%) had detectable values and mean BCC was 0.86 ng/mL (range < LOD-13.2). Mean per capita dietary intake of chlordecone was estimated at 3.3 microg/day (range: 0.1-22.2). Blood chlordecone levels were significantly correlated with food exposure predicted from the empirical weight models (r=0.47, p<0.0001) and, to a lesser extent, with chlordecone intake estimated from food consumption and food contamination data (r=0.20, p=0.007). Main contributors to chlordecone exposure included seafood, root vegetables, and Cucurbitaceous. CONCLUSION: These results show that the Timoun FFQ provides valid estimates of chlordecone exposure. Estimates from empirical weight models correlated better with blood levels of chlordecone than did estimates from the dietary intake assessment.

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Fichiers liés : Pesticide_exposureofpregnantwomeninGuadeloupe.pdf

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Nicolas DegallierCharly FavierChristophe MenkesMatthieu LengaigneWalter RamalhoRégilo SouzaJacques ServainJean-Philippe Boulanger
• Organismes : Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques Institut des Sciences de l'Evolution de Montpellier Variabilité climatique tropicale et globale Variabilité climatique tropicale et globale Instituto Evandro Chagas Instituto Evandro Chagas Variabilité climatique tropicale et globale Variabilité climatique tropicale et globale
• Publié dans Climatic Change le 30/10/2020

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Résumé : Dengue fever is the most prevalent mosquito-borne viral disease of humans in tropical lands. As an efficient vaccine is not yet available, the only means to prevent epidemics is to control mosquito populations. These are influenced by human behavior and climatic conditions and thus, need constant effort and are very expansive. Examples of succeeded prevention are rare because of the continuous reintroduction of virus or vector from outside, or growing resistance of mosquito populations to insecticides. Climate variability and global warming are other factors which may favour epidemics of dengue. During a pilot study in Claris EC project, a model for the transmission of dengue was built, to serve as a tool for estimating the risk of epidemic transmission and eventually forecasting the risk under climatic change scenarios. An ultimate objective would be to use the model as an early warning system with meteorological forecasts as input, thus allowing better decision making and prevention.

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• Type de publi. : Article dans une revue
• Date de publi. : 01/02/2010
• Auteurs : Afif AfifLorella MinottiPhilippe KahaneDominique M. Hoffmann
• Organismes : Integration centrale de la douleur chez l'homme Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL] ANTE-INSERM U836, équipe 9, Dynamique des réseaux synchrones épileptiques ANTE-INSERM U836, équipe 9, Dynamique des réseaux synchrones épileptiques Neurochirurgie
• Publié dans Epilepsia le 22/10/2020

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Résumé : PURPOSE: Different lines of evidence have suggested an involvement of the insular cortex in speech production. These have included results from lesion studies, functional imaging techniques, and electrical stimulation of the human insular cortex during invasive evaluation of epileptic patients. METHODS: We evaluated 25 patients who had drug refractory focal epilepsy with at least one electrode stereotactically implanted in the insular cortex. RESULTS: Eight responses to insular cortex electrical stimulation were reported by five patients as speech arrest (five responses) and a lowering of voice intensity (three responses). CONCLUSIONS: Data from this study implicate the middle short gyrus of the insula in the production of speech and show the importance of intrainsular electrode implantation during invasive pre-resection evaluation by stereo-electroencephalography (SEEG) when speech arrest occurs early in seizure semiology.

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Fichiers liés : Afif-2010-Middle_short_gyrus_ME.pdf

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• Type de publi. : Article dans une revue
• Date de publi. : 29/01/2010
• Auteurs : Emilie HangenDaniela de ZioMatteo BordiChanglian ZhuPhilippe DessenFanny CaffinSylvie LachkarJean-Luc PerfettiniVladimir LazarJean BenardGian Maria FimiaMauro PiacentiniFrancis HarperGérard PierronJosé Miguel VicencioPaule BénitAnderson de AndradeGünter HöglingerCarsten CulmseePierre RustinKlas BlomgrenFrancesco CecconiGuido KroemerNazanine Modjtahedi
• Organismes : Apoptose, cancer et immunité Laboratory of Molecular Neuroembryology Laboratory of Molecular Neuroembryology Center for Brain Repair and Rehabilitation Génomes et cancer Apoptose, cancer et immunité Apoptose, cancer et immunité Apoptose, cancer et immunité Génomique Fonctionnelle et Biologie Systémique pour la Santé Interactions moléculaires et cancer National Institute for Infectious Diseases National Institute for Infectious Diseases Réplication de l'ADN - Ultrastructure de la cellule Réplication de l'ADN - Ultrastructure de la cellule Apoptose, cancer et immunité Physiopathologie, conséquences fonctionnelles et neuroprotection des atteintes du cerveau en développement Experimental Neurology Experimental Neurology Department of Pharmacy Physiopathologie, conséquences fonctionnelles et neuroprotection des atteintes du cerveau en développement Center for Brain Repair and Rehabilitation Laboratory of Molecular Neuroembryology Apoptose, cancer et immunité Apoptose, cancer et immunité
• Publié dans Cell Death and Differentiation le 29/10/2020

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Résumé : Apoptosis-Inducing factor (AIF) plays important supportive as well as potentially lethal roles in neurons. Under normal physiological conditions, AIF is a vital redox-active mitochondrial enzyme, whereas in pathological situations, it translocates from mitochondria to the nuclei of injured neurons and mediates apoptotic chromatin condensation and cell death. Here, we reveal the existence of a brain-specific isoform of AIF, AIF2, whose expression increases as neuronal precursor cells differentiate. AIF2 arises from the utilization of the alternative exon 2b, yet uses the same remaining 15 exons as the ubiquitous AIF1 isoform. AIF1 and AIF2 are similarly imported to mitochondria where they anchor to the inner membrane facing the intermembrane space. However, the mitochondrial inner membrane sorting signal (IMSS) encoded in the exon 2b of AIF2 is more hydrophobic than that of AIF1, indicating a stronger membrane anchorage of AIF2 than AIF1. AIF2 is more difficult to be desorbed from mitochondria than AIF1 upon exposure to non-ionic detergents or basic pH. Furthermore, AIF2 dimerizes with AIF1, thereby preventing its release from mitochondria. Conversely, it is conceivable that a neuron-specific AIF isoform, AIF2, may have been "designed" to be retained in mitochondria and to minimize its potential neurotoxic activity.

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Fichiers liés : PEER_stage2_10.1038%2Fcdd.2009.211.pdf

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• Type de publi. : Article dans une revue
• Date de publi. : 27/01/2010
• Auteurs : Sébastien JoanninJean-Jacques CorneePhilippe MunchMichel FornariIuliana VasilievWout KrijgsmanSamuel NahapetyanIvan GabrielyanVincent OllivierPaul RoironChristine Chataigner
• Organismes : Laboratoire Chrono-environnement (UMR 6249) PaleoEnvironnements et PaleobioSphere Maison des Sciences de l'Homme et de l'Environnement Claude Nicolas Ledoux (UAR 3124) Géosciences Montpellier Géosciences Montpellier Géoazur Universiteit Utrecht / Utrecht University [Utrecht] Universiteit Utrecht / Utrecht University [Utrecht] ARCHEORIENT - Environnements et sociétés de l'Orient ancien ARCHEORIENT - Environnements et sociétés de l'Orient ancien Laboratoire méditerranéen de préhistoire Europe-Afrique Centre de Bio-Archéologie et d'Ecologie ARCHEORIENT - Environnements et sociétés de l'Orient ancien
• Publié dans Earth and Planetary Science Letters le 01/11/2020

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Résumé : Plio-Pleistocene diatomitic sequences in the Shamb paleo-lake (South Armenia, Lesser Caucasus) offer a rare opportunity to give new insights on the paleo-climate of Western Asia. We present an integrated palynological, 40Ar/39Ar geochronologic and magnetostratigraphic study for the most complete section in the sedimentary deposits of the Shamb paleo-lake. 40Ar/39Ar dating of two volcaniclastic layers provided ages of 1.24 ± 0.03 and 1.16 ± 0.02 Ma (2. Magnetostratigraphic data show that the entire Shamb section is of reversed polarity which, combined with 40Ar/39Ar dating, suggests that the entire section correlates with part of the Matuyama period (1.785-1.070 Ma). Pollen assemblages and macroremains diversity clearly show an alternation of glacial and interglacial phases. Age calibrations and accumulation rate extrapolation allow a direct correlation of climate changes with the global isotopic curve, and show that the Shamb section probably ranges from approximately 1.300 to 1.080 Ma (marine isotopic stages 40 to 31). The vegetation of the Lesser Caucasus developed in a mosaic pattern in a Pleistocene continental, mostly arid climate, comparable to the present-day climate. The observed vegetation changes record a dominant climate response to the obliquity orbital parameter, but the influence of precession could not be established from the Shamb data. Pollen and macroflora both indicate that glacial periods were cold and dry and that interglacials were warm with local humidity. The early Pleistocene climatic model for Western Asia is thus similar to the climatic model for the Mediterranean area.

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