Les calcifications pulmonaires métastatiques [Pulmonary metastatic calcification].

INTRODUCTION: The lung is the organ most frequently involved by metastatic calcification. This condition is probably under-diagnosed, the patients usually being asymptomatic. This article summarizes the current knowledge concerning pulmonary metastatic calcification. BACKGROUND: The pathogenesis of pulmonary metastatic calcification is not well known, but it involves phosphate-calcium balance, renal function and pH. The most frequently encountered aetiologies are hyperparathyroidism, neoplastic bony lesions, and renal failure. The definitive diagnosis is achieved by histology, radiological examinations being insensitive. The clinical manifestations are various and can include a pulmonary restrictive syndrome, diffusion abnormalities, hypoxaemia and respiratory failure. The latter can be severe and influence the prognosis adversely: 19 cases of fatal pulmonary metastatic calcification have been reported. The treatment is aetiological and symptomatic. VIEWPOINT: The prognostic factors for a poor outcome of this potentially lethal condition remain to be determined. The management of asymptomatic patients is also uncertain. CONCLUSIONS: Pulmonary metastatic calcification is a rare condition of complex pathogenesis. The clinical manifestations are varied, ranging from asymptomatic to severe, even fatal.

Calcium entry blockade attenuates the acute blood pressure rise induced by cigarette smoking.

The purpose of this study was to assess whether the administration of a calcium entry blocker can prevent the acute blood pressure rise induced by cigarette smoking. Seven male habitual smokers were included. After 45 min of equilibration, they took in randomized single-blind fashion at a 1 week interval either a placebo or nifedipine, 10 mg p.o. Thirty minutes thereafter, the subjects smoked within 10 min two cigarettes containing 1.4 mg of nicotine each. In addition to heart rate and skin blood flow (laser Doppler method), blood pressure of the median left finger was monitored continuously for 100 min using a noninvasive device (Finapres). Nifedipine induced an increase in skin blood flow that was not influenced by smoking. This skin blood flow response was observed although nifedipine had by itself no effect on systemic blood pressure. The calcium antagonist markedly attenuated the blood pressure rise induced by cigarette smoking. However, it tended to accentuate the heart rate acceleration resulting from inhalation of nicotine-containing smoke.

Members of the PHO1 gene family show limited functional redundancy in phosphate transfer to the shoot, and are regulated by phosphate deficiency via distinct pathways.

The PHO1 family comprises 11 members in Arabidopsis thaliana. In order to decipher the role of these genes in inorganic phosphate (Pi) transport and homeostasis, complementation of the pho1 mutant, deficient in loading Pi to the root xylem, was determined by the expression of the PHO1 homologous genes under the control of the PHO1 promoter. Only PHO1 and the homologue PHO1;H1 could complement pho1. The PHO1;H1 promoter was active in the vascular cylinder of roots and shoots. Expression of PHO1;H1 was very low in Pi-sufficient plants, but was strongly induced under Pi-deficient conditions. T-DNA knock-out mutants of PHO1;H1 neither showed growth defects nor alteration in Pi transport dynamics, or Pi content, compared with wild type. However, the double mutant pho1/pho1;h1 showed a strong reduction in growth and in the capacity to transfer Pi from the root to the shoot compared with pho1. Grafting experiments revealed that phenotypes associated with the pho1 and pho1/pho1;h1 mutants were linked to the lack of gene expression in the root. The increased expression of PHO1;H1 under Pi deficiency was largely controlled by the transcription factor PHR1 and was suppressed by the phosphate analogue phosphite, whereas the increase of PHO1 expression was independent of PHR1 and was not influenced by phosphite. Together, these data reveal that although transfer of Pi to the root xylem vessel is primarily mediated by PHO1, the homologue PHO1;H1 also contributes to Pi loading to the xylem, and that the two corresponding genes are regulated by Pi deficiency by distinct signal transduction pathways.

Microtubule-associated protein 1B binds glyceraldehyde-3-phosphate dehydrogenase.

Microtubule-associated protein 1B, MAP1B, is a major cytoskeletal protein during brain development and one of the largest brain MAPs associated with microtubules and microfilaments. Here, we identified several proteins that bind to MAP1B via immunoprecipitation with a MAP1B-specific antibody, by one and two-dimensional gel electrophoresis and subsequent mass spectrometry identification of precipitated proteins. In addition to tubulin and actin, a variety of proteins were identified. Among these proteins were glyceraldehyde-3-phosphate dehydrogenase (GAPDH), heat shock protein 8, dihydropyrimidinase related proteins 2 and 3, protein-L-isoaspartate O-methyltransferase, beta-spectrin, and clathrin protein MKIAA0034, linking either directly or indirectly to MAP1B. In particular, GAPDH, a key glycolytic enzyme, was bound in large quantity to the heavy chain of MAP1B in adult brain tissue. In vitro binding studies confirmed a direct binding of GAPDH to MAP1B. In PC12 cells, GAPDH was found in cytoplasm and nuclei and partially co-localized with MAP1B. It disappeared from the cytoplasm under oxidative stress or after a disruption of cytoskeletal elements after colcemid or cytochalasin exposure. GAPDH may be essential in the local energy provision of cytoskeletal structures and MAP1B may help to keep this key enzyme close to the cytoskeleton.

Neuronal calcium channel mutation in a patient with congenital ataxia and attacks of hemiplegic migraine with cerebral edema

Background: Familial Hemiplegic Migraine (FHM), characterized by a prolonged unilateral hemiparesis, mainly results from mutations in the alpha-1a subunit of the calcium channel gene CACNA1A that can also cause two other dominantly inherited neurological disorders, Episodic Ataxia type 2 (EA2, with sometimes migrainous headaches) and Spinocerebellar Ataxia type 6 (SCA6, late-onset and progressive). A same mutation can have different clinical expression in a family (hemiplegic migraine, migraine-coma, cerebellar ataxia). CACNA1A mutations in FHM are usually missense, leading to gain-of-function, while truncating mutations leading to loss-of-function are usually associated with EA2. Case report: This 9-year-old girl was seen as a baby for hypotonia and transient vertical nystagmus. Her first brain MRI was normal. She evolved as a congenital ataxia, but since the age of two, she had attacks of coma, hemiparesis (either side), partial seizures, dystonic movements and fever. Attacks were initially triggered by minor head bumps, subsequently spontaneous. Brain MRIs in the acute stage always showed transient unilateral hemisphere swelling. Follow-up images revealed atrophic lesions in the temporo-occipital regions and cerebellar atrophy. A prophylactic trial with flunarizine was ineffective. Acetazolamide was recently introduced. Methods: Since our patient shared features of both FHM and EA2, we studied the CACNA1A gene by direct sequencing in the patient's and parents' DNA. Results: We identified an unreported de novo heterozygous deletion of three base pairs (c.4503_4505delCTT) predicting the deletion of one amino acid (p.Phe1502del). The CACNA1A protein contains 4 domains, each formed by six transmembrane segments. The deletion is located in a highly conserved region in segment 6 (S6) of the third domain. Mutations in S6 segments of calcium channels change single-channel conductance and channel selectivity, most resulting in loss-of-function. Outlook: In vitro expression studies of the identified mutation are underway, aiming at understanding its functional consequences and finding an efficient treatment.

Calcium Microdomains Control Exo-Endocytosis of Synaptic-Like Microvesicles in Astrocytes

During the last decade, the discovery that astrocytes possess a nonelectrical form of excitability (Ca21-excitability) that leads to the release of chemical transmitters, an activity called ''gliotransmission'', indicates that these cells may have additional important roles in brain function. Elucidating the stimulus-secretion coupling leading to the exocytic release of chemical transmitters (such as glutamate, Bezzi et al., Nature Neurosci, 2004) may therefore clarify i) whether astrocytes represent in full a new class of secretory cells in the brain and ii) whether they can participate to the fast brain signaling in the brain. Here by using a recently developed approach for studying vesicle recycling dynamics at synapses (Voglmaier et al., Neuron, 2006; Balaji and Ryan, PNAS, 2007) combined with epifluorescence and total internal reflection fluorescence (TIRF) imaging, we investigated the spatiotemporal characteristics of stimulus-secretion coupling leading glutamate exocytosis of synaptic-like microvesicles (SLMVs) in astrocytes. We performed the analysis at both the whole-cell and single-vesicle levels providing the first system for comparing exo-endocytic processes in astrocytes with those in neurons. Both the time course and modalities of secretion in astrocytes present more similarities to neurons then previously expected. We found that 1. the G-protein-coupled receptor (GPCR)-evoked exocytosis reached the maximum on a ms time scale and that 2. ER tubuli formed sub-micrometer domains beneath the plasma membrane in close proximity to exocytic vesicles, where fusion events were spatiotemporally correlated with fast Ca21 events.

Defining molecular components of symbiotic phosphate uptake in rice

Phosphate (Pi) acquisition of crops via arbuscular mycorrhizal (AM) symbiosis acquires increasing importance due to the limited rock Pi reserves and the demand for environmentally sustainable agriculture. However, the symbiotic Pi uptake machinery has not been characterized in any monocotyledonous plant species. Among these, rice is the primary staple food for more than half of the human population and thus central for future food security. However, the relevance of the AM symbiosis for rice Pi nutrition is presently unclear. Here, we show that 70% of the overall Pi acquired by rice is delivered via the symbiotic route. To better understand this pathway we combined genetic, molecular and physiological approaches to determine the specific functions of the two rice Pi transporters, PT11 and PT13, which are expressed only during AM symbiosis. The PT11 lineage of proteins is present in mono- and dicotyledons whereas PT13, while found across the Poaceae, is absent from dicotyledons. Surprisingly, mutations in either PT11 or PT13 affected fungal colonization and arbuscule formation demonstrating that both genes are essential for AM symbiosis between rice and Glomus intra.rad.ices. Importantly, for symbiotic Pi uptake, only PT11 is necessary and sufficient. We found that mycorrhizal rice, remarkably, received almost all Pi via the symbiotic route. Such dominating mycorrhizal Pi uptake was found in plants grown under controlled conditions as well as in field soils, suggesting that the AM symbiosis is relevant for the Pi nutrition of field grown rice. Development of smaller arbuscules in PT11 mutants suggested that symbiotic Pi signaling is required for fungal nourishment by the plant. However, co-culture of mutant with wild type nurse plants did not restore normal arbuscule size in mutant roots, indicating that other factors than malnutrition accounted for the altered arbuscule phenotype. Surprisingly, the loss of PT13 did not affect symbiotic Pi uptake although it impacted arbuscule morphology, suggesting that PT13 is involved in signaling during arbuscule development. However, induction of PT13 was not only monitored in arbusculated cells but also in inner cortex cells of non-inoculated roots of plants grown under high Pi fertilization conditions. According to preliminary observations, PT13 localized at the tonoplast in arbusculated and non-arbusculated cells, suggesting that it might be involved in transporting Pi into the vacuole, possibly for maintaining cellular Pi homeostasis. The further investigation showed that fungal colonization level was significantly affected in the crown roots of two ptlS mutant alleles, but not in large lateral roots, implying the possible role of PT13 for maintaining Pi homeostasis in the crown roots. - L'acquisition de phosphate (Pi) par les plantes cultivées s'effectue grâce à une symbiose mycorhizienne arbasculaire (AM). L'étude de cette symbiose devient fondamentale puisque d'une part, les réserves en phosphate minéral sont limitées, et, d'autre part, la demande pour une agriculture écologiquement soutenable se renforce. La machinerie d'absorption symbiotique du phosphate n'est cependant pas encore élucidée chez les plantes monocotylédones. Parmi celles-ci, le riz occupe une place primordiale. Aliment de base pour plus de la moitié de la population mondiale, il revêt de ce fait une dimension essentielle en termes de sécurité alimentaire. Pourtant, l'importance de la symbiose AM chez le riz dans le processus d'acquisition du phosphate n'est, encore de nos jours, que peu comprise. Dans cette étude, nous montrons que 70% du phosphate acquis par le riz est mis à disposition de la plante grâce à la symbiose AM. Afin de mieux comprendre ce mécanisme, nous avons employé des approches physiologiques et génétiques nous permettant de déterminer les fonctions spécifiques de deux transporteurs de Pi, PT11 et PT13, présents chez le riz et exprimés uniquement durant la symbiose AM. La famille de gènes à laquelle appartient PT11 est présente chez les monocotylédones ainsi que chez les dicotylédones tandis que PT13, bien que retrouvé au sein des Poaceae, est absent chez les dicotylédones. Etonnamment, des versions mutées de PT11 ou de PT13 affectent la colonisation par le champignon endo-mycorhizien ainsi que la formation d'arbuscules, démontrant l'importance de ces deux gènes dans la symbiose AM entre le riz et Glomus intraradices. Il est à noter que seul PT11 se révèle nécessaire et suffisant pour l'apport de Pi grâce à la symbiose. Nous avons observé que la presque totalité du phosphate dont dispose le riz lors d'une symbiose AM provient du champignon. De telles proportions ont été observées tant chez des plantes cultivées en conditions contrôlées que chez des plantes cultivées dans les champs. Cela suggère l'importance de la symbiose AM dans le processus d'acquisition du Pi chez le riz cultivé à l'extérieur. Le développement d'arbuscules plus petits chez le mutant PT11 tend à montrer qu'une voie signalétique impliquant le Pi symbiotique est nécessaire pour l'entretien du champignon par la plante. Toutefois, une co-culture du mutant avec des plantes sauvages ne permet pas de restaurer des arbuscules de taille normale dans les racines du mutant. Ce résultat indique le rôle de facteurs autres que la malnutrition aboutissant à la formation d'arbuscules altérés. Si la perte de PT13 n'affecte pas l'acquisition de phosphate symbiotique, la morphologie de l'arbuscule est, quant à elle, modifiée. Ceci suggère un rôle de PT13 durant le développement de l'arbuscule. Or, l'induction de PT13 est non seulement détectée dans des cellules contenant des arbuscules mais également dans des cellules du cortex, ceci chez des plantes cultivées sans champignon mais dans des conditions de fortes concentrations en engrais phosphaté. En accord avec des observations précédentes, PT13 est localisé au niveau du tonoplaste des cellules contenant ou non des arbuscules. Ceci suggère que PT13 pourrait être impliqué dans le transport du Pi vers la vacuole, éventuellement pour maintenir une certaine homéostasie du phosphate. Dans cette étude, nous démontrons également que le niveau de colonisation par le champignon est affecté de manière significative dans les racines principales des deux allèles du mutants ptl3, mais pas dans les grosses racines latérales. Cela impliquerait un rôle possible de PT13 dans le maintien de l'homéostasie du phosphate dans les racines principales. RESUME POUR UN LARGE PUBLIC Le phosphate (Pi), l'un des éléments minéraux essentiel au développement des plantes, se trouve généralement en faible quantité dans le sol, limitant ainsi la croissance des plantes. Le rendement de la production agricole dépend dès lors de l'addition d'engrais contenant du phosphate inorganique (Pi), obtenu à partir de ressources minières riches en phosphate. Or, ces ressources devraient être épuisées d'ici la fin du siècle. Les racines des plantes possèdent des transporteurs de phosphate efficaces leur permettant d'acquérir rapidement le Pi présent dans le sol. Comme le Pi s'avère immobile dans le sol, l'absorption rapide par les racines crée des zones pauvres en Pi autour des systèmes racinaires. Pour surmonter cet obstacle, les plantes ont développé une symbiose avec des champignons endomycorhiziens, la symbiose mycorhizienne arbusculaire (AM). Cette association leur donne accès à d'autres ressources en phosphate puisque le mycélium de ces champignons se développe sur une surface 100 fois supérieure à celle des racines. Cela augmente considérablement la surface de nutrition, dépassant ainsi la zone appauvrie en Pi. Le phosphate, transporté grâce au champignon jusqu'à l'intérieur des racines, est fourni à la plante par le biais de structures établies à l'intérieur des cellules végétales, appelées arbuscules. De leur côté, les plantes possèdent des transporteurs spécifiques afin de recevoir le Pi fourni par les champignons. A l'heure actuelle, la machinerie nécessaire à cette absorption a été uniquement décrite chez des plantes dicotylédones. Or, comprendre l'apport de phosphate par les champignons mycorhiziens s'avère particulièrement pertinent dans le cas des espèces monocotylédones cultivées telles que les céréales. Ces dernières constituent en effet la majeure partie de l'alimentation humaine. Parmi les céréales, le riz demeure l'aliment de base de la population mondiale, d'où son importance en terme de sécurité alimentaire. Durant mon travail de thèse, j'ai identifié et caractérisé le transporteur du riz impliqué dans l'apport de phosphate par ce type de symbiose AM. J'ai également démontré que le riz, lorsqu'il vit en symbiose, bénéficie de la presque totalité du Pi transporté par le champignon. Environ 40% de la production globale de riz est cultivée dans des conditions permettant la symbiose avec des mycorhizes arbusculaires. Les variétés de riz adaptées à ces conditions aérobiques deviennent des alternatives favorables aux cultivars actuels nécessitant une forte irrigation. Elles se révèlent en effet plus tolérantes aux pénuries d'eau et permettent l'utilisation de pratiques agricoles moins intensives. Les données présentées dans cette étude enrichissent nos connaissances concernant l'absorption du phosphate chez le riz grâce à la symbiose AM. Ces connaissances peuvent s'avérer décisives pour le développement de cultivars du riz plus adaptés à une agriculture écologiquement soutenable.

Effect of supplementation with vitamin D3 and calcium on quantitative ultrasound of bone in elderly institutionalized women: a longitudinal study.

Supplementation of elderly institutionalized women with vitamin D and calcium decreased hip fractures and increased hip bone mineral density. Quantitative ultrasound (QUS) measurements can be performed in nursing homes, and easily repeated for follow-up. However, the effect of the correction of vitamin D deficiency on QUS parameters is not known. Therefore, 248 institutionalized women aged 62-98 years were included in a 2-year open controlled study. They were randomized into a treated group (n = 124), receiving 440 IU of vitamin D3 combined with 500 mg calcium (1250 mg calcium carbonate, Novartis) twice daily, and a control group (n = 124). One hundred and three women (42%), aged 84.5 +/- 7.5 years, completed the study: 50 in the treated group, 53 in the controls. QUS of the calcaneus, which measures BUA (broadband ultrasound attenuation) and SOS (speed of sound), and biochemical analysis were performed before and after 1 and 2 years of treatment. Only the results of the women with a complete follow-up were taken into account. Both groups had low initial mean serum 25-hydroxyvitamin D levels (11.9 +/- 1.2 and 11.7 +/- 1.2 micrograms/l; normal range 6.4-40.2 micrograms/l) and normal mean serum parathyroid hormone (PTH) levels (43.1 +/- 3.2 and 44.6 +/- 3.5 ng/l; normal range 10-70 ng/l, normal mean 31.8 +/- 2.3 ng/l). The treatment led to a correction of the metabolic disturbances, with an increase in 25-hydroxyvitamin D by 123% (p < 0.01) and a decrease in PTH by 18% (p < 0.05) and of alkaline phosphatase by 15% (p < 0.01). In the controls there was a worsening of the hypovitaminosis D, with a decrease of 25-hydroxyvitamin D by 51% (p < 0.01) and an increase in PTH by 51% (p < 0.01), while the serum calcium level decreased by only 2% (p < 0.01). After 2 years of treatment BUA increased significantly by 1.6% in the treated group (p < 0.05), and decreased by 2.3% in the controls (p < 0.01). Therefore, the difference in BUA between the treated subjects and the controls (3.9%) was significant after 2 years (p < 0.01). However, SOS decreased by the same amount in both groups (approximately 0.5%). In conclusion, BUA, but not SOS, reflected the positive effect on bone of supplementation with calcium and vitamin D3 in a population of elderly institutionalized women.

Calcium-mediated activation of pyruvate dehydrogenase in severely injured postischemic myocardium.

Indirect evidence suggests that activity of pyruvate dehydrogenase (PDH) influences recovery of the myocardium after transient ischemia. The present study examined the relationship between postischemic injury and activity of PDH and the role of mitochondrial calcium uptake for observed changes in PDH activity. Isovolumically beating isolated rat hearts perfused with erythrocyte-enriched buffer containing glucose, palmitate, and insulin were submitted to either 20 or 35 min of no-flow ischemia. After 20 min of no-flow ischemia, hearts exhibited complete recovery of developed left ventricular pressure (DLVP). The proportion of myocardial PDH in the active state was modestly increased to 38% (compared with 13% in control hearts) without a change in glucose oxidation. In contrast, in hearts subjected to 35 min of no-flow ischemia (which exhibited poor recovery of DLVP), there was marked stimulation of glucose oxidation (+460%; P < 0.01) and pronounced increase in the active fraction of PDH to 72% (P < 0.01). Glycolytic flux was not significantly altered. Ruthenium red (6 microM) completely abolished the activation of PDH and the increase in glucose oxidation. The results indicate that variable stimulation of glucose oxidation during reperfusion is related to different degrees of activation of PDH, which depends on the severity of the ischemic injury. Activation of PDH seems to be mediated by myocardial calcium uptake.

Coordination between zinc and phosphate homeostasis involves the transcription factor PHR1, the phosphate exporter PHO1, and its homologue PHO1;H3 in Arabidopsis.

Interactions between zinc (Zn) and phosphate (Pi) nutrition in plants have long been recognized, but little information is available on their molecular bases and biological significance. This work aimed at examining the effects of Zn deficiency on Pi accumulation in Arabidopsis thaliana and uncovering genes involved in the Zn-Pi synergy. Wild-type plants as well as mutants affected in Pi signalling and transport genes, namely the transcription factor PHR1, the E2-conjugase PHO2, and the Pi exporter PHO1, were examined. Zn deficiency caused an increase in shoot Pi content in the wild type as well as in the pho2 mutant, but not in the phr1 or pho1 mutants. This indicated that PHR1 and PHO1 participate in the coregulation of Zn and Pi homeostasis. Zn deprivation had a very limited effect on transcript levels of Pi-starvation-responsive genes such as AT4, IPS1, and microRNA399, or on of members of the high-affinity Pi transporter family PHT1. Interestingly, one of the PHO1 homologues, PHO1;H3, was upregulated in response to Zn deficiency. The expression pattern of PHO1 and PHO1;H3 were similar, both being expressed in cells of the root vascular cylinder and both localized to the Golgi when expressed transiently in tobacco cells. When grown in Zn-free medium, pho1;h3 mutant plants displayed higher Pi contents in the shoots than wild-type plants. This was, however, not observed in a pho1 pho1;h3 double mutant, suggesting that PHO1;H3 restricts root-to-shoot Pi transfer requiring PHO1 function for Pi homeostasis in response to Zn deficiency.

Role of homer 1 proteins in the calcium signaling pathway(s) underlying exo-endocytosis processes of glutamatergic slmvs in astrocytes

The discovery that astrocytes possess a nonelectrical form of excitability (calcium excitability) that leads to the release of chemical transmitters, an activity called gliotransmission, indicates that these cells may have additional important roles in brain function. Elucidating the stimulussecretion coupling leading to the exocytic release of chemical transmitters (such as glutamate, Bezzi et al., Nature Neurosci, 2004) may therefore clarify i) whether astrocytes represent in full a new class of secretory cells in the brain and ii) whether they can participate to the fast brain signaling in the brain. We have recently discovered the existence in astrocytes of functional sub-membrane microdomains of calcium release from the internal stores in response to mGluR5 activation (Marchaland et al., J of Neurosci., 2008). Such sub-plasma membrane calcium microdomains control exocytosis of astrocytic glutamate signaling to neurons. Homer proteins are scaffold proteins controlling calcium signaling in different cellular microdomains, including dendritic spines in neurons (Sala et al., J of Neurosci., 2005). Thus, similarly to dendritic pines, Homer1 could be implicated in the coupling between astrocytic mGluR5 and IP3Rs on the ER. Here, by using a recently developed approach for studying vesicle recycling dynamics at synapses (Voglmaier et al., Neuron, 2006; Balaji and Ryan, PNAS, 2007) combined with epifluorescence and total internal reflection fluorescence (TIRF) imaging, we investigated the involvement of Homer1 proteins in the calcium dependent stimulus-secretion coupling leading glutamate exocytosis of synaptic-like microvesicles (SLMVs) in astrocytes.

Changes in Aortic Pulse Wave Velocity in Hypertension Post-Menopausal Women: Comparison Between Calcium Channel Blocker (CCB) Vs Angiotensin Receptor Blocker (ARB) Regimen

Objective: To compare effects of a non-renin-angiotensin system (RAS) blocker, using a CCB, or a RAS blocker, using an ARB regimen on the arterial stiffness reduction in postmenopausal hypertensive women. Methods: In this prospective study, a total of 125 hypertensive women (age: 61.4_6 yrs; 98% Caucasian; BW: 71.9_14 kg; BMI: 27.3_5 kg/m2; SBP/ DBP: 158_11/92_9 mmHg) were randomized between ARB (valsartan 320mg_HCTZ) and CCB (amlodipine 10mg _ HCTZ). The primary outcome was carotid-femoral pulse wave velocity (PWV) changes after 38 weeks of treatment. Results: There were no significant differences in baseline demographic data between the two groups. Both treatments effectively lowered BP at the end of the study with similar (p>0.05) reductions in the valsartan (_22.9/_10.9 mmHg) and amlodipine based (_25.2/_11.7 mmHg) treatment groups. Despite a lower (p<0.05 for DBP) central SBP/DBP in the CCB group (_19.2/_10.3 mmHg) compared to the valsartan group (_15.7/_7.6 mmHg) at week 38, a similar reduction in carotid-femoral PWV (_1.7 vs _1.9 m/sec; p>0.05) was observed between both groups. The numerically larger BP reduction observed in the CCB group was associated with a much higher incidence of peripheral edema (77% vs 14%) than the valsartan group. Conclusion: In summary, BP lowering in postmenopausal women led to a reduction in arterial stiffness assessed by PWV measurement. Both regimens reduced PWV at 38 weeks of treatment to a similar degree, despite differences in BP lowering suggesting that the effect of RAS blockade to influence PWV may partly be independent of BP.

Consommation d'aliments riches en calcium dans la population adulte de Suisse romande et du Tessin. [Consumption of calcium-rich food in the adult population of French-speaking Switzerland and of Tessin].

Food intake high in calcium content is important in the development of skeleton and the prevention of osteoporosis. From a public health perspective, it is therefore important to know the dietary calcium intake of a population. Two population surveys in the French and Italian parts of Switzerland (MONICA, 1988-1989, and Geneva, 1991), were combined to study nutritional habits related to calcium intake. A random population sample, aged 35 et 65 years, answered to a 24 hour recall questionnaire, either self-administered (MONICA, cantons of Vaud, Fribourg and Tessin, N = 2734) or by phone (canton of Geneva, N = 475). In the 4 cantons, for the previous day, 60% of participants ate dairy products, particularly whole milk and cheese. They drunk 3-4 dl/day of milk. A significant proportion (10%) of french and italian speaking Swiss did not consume any food high in calcium content. In Geneva, the mean daily calcium intake was 656 mg in men and 489 mg in women. In conclusion 1) eating habits related to calcium intake are similar across cantons; 2) women consume dairy products more frequently than men, but in smaller quantities; 3) about 60% of men and 80% of women do not get the daily amount of calcium recommended for the prevention of osteoporosis.

Dairy calcium supplementation in overweight or obese persons: its effect on markers of fat metabolism

BACKGROUND: Dairy calcium supplementation has been proposed to increase fat oxidation and to inhibit lipogenesis. OBJECTIVE: We aimed to investigate the effects of calcium supplementation on markers of fat metabolism. DESIGN: In a placebo-controlled, crossover experiment, 10 overweight or obese subjects who were low calcium consumers received 800 mg dairy Ca/d for 5 wk. After 4 wk, adipose tissue was taken for biopsy for analysis of gene expression. Respiratory exchange, glycerol turnover, and subcutaneous adipose tissue microdialysis were performed for 7 h after consumption of 400 mg Ca or placebo, and the ingestion of either randomized slow-release caffeine (SRC; 300 mg) or lactose (500 mg). One week later, the test was repeated with the SRC or lactose crossover. RESULTS: Calcium supplementation increased urinary calcium excretion by 16% (P = 0.017) but did not alter plasma parathyroid hormone or osteocalcin concentrations. Resting energy expenditure (59.9 +/- 3.0 or 59.6 +/- 3.3 kcal/h), fat oxidation (58.4 +/- 2.5 or 53.8 +/- 2.2 mg/min), plasma free fatty acid concentrations (0.63 +/- 0.02 or 0.62 +/- 0.03 mmol/L), and glycerol turnover (3.63 +/- 0.41 or 3.70 +/- 0.38 micromol . kg(-1) . min(-1)) were similar with or without calcium, respectively. SRC significantly increased free fatty acid concentrations, resting fat oxidation, and resting energy expenditure. During microdialysis, epinephrine increased dialysate glycerol concentrations by 250% without and 254% with calcium. Expression of 7 key metabolic genes in subcutaneous adipose tissue was not affected by calcium supplementation. CONCLUSION: Dairy calcium supplementation in overweight subjects with habitually low calcium intakes failed to alter fat metabolism and energy expenditure under resting conditions and during acute stimulation by caffeine or epinephrine