Association between Early Ischemic Changes and Collaterals in Acute Stroke: A Retrospective Study.

BACKGROUND AND PURPOSE: The quality of leptomeningeal collaterals may influence the speed of infarct progression in acute stroke. Our main objective was to evaluate the association of leptomeningeal collateral score and its interaction with time with ischemic changes on CT in patients with acute stroke. MATERIALS AND METHODS: Adult patients with acute stroke symptoms and anterior circulation large-vessel occlusion on CTA from 2015 to 2019 were included. Routinely performed NCCT and multiphase CTA were reviewed to assess ASPECTS and the leptomeningeal collateral score. We built multivariate regression models to assess the association between leptomeningeal collateral score and its interaction with time and ASPECTS. Performance measures to predict poor ASPECTS at different time thresholds (identified with receiver operating characteristic curve analysis) were estimated in a subgroup of patients with poor leptomeningeal collateral scores. RESULTS: Leptomeningeal collateral scores 0-1 were associated with lower ASPECTS, and the model with dichotomized and trichotomized leptomeningeal collateral score showed a significant multiplicative interaction between time and the leptomeningeal collateral score. The negative predictive value for poor ASPECTS was >0.9 for at least the first 3 hours from stroke onset to imaging, and the positive predictive value was <0.5 for every time threshold tested in the subgroup of patients with leptomeningeal collateral scores 0-3. CONCLUSIONS: Poor (0-1) leptomeningeal collateral scores were associated with lower ASPECTS, and an increase in time has a multiplicative interaction with the leptomeningeal collateral score on ASPECTS.

The regular consumption of a polyphenol-rich apple does not influence endothelial function: a randomised double-blind trial in hypercholesterolemic adults.

BACKGROUND/OBJECTIVES: Epidemiological studies suggest that apple consumption is associated with a reduction in cardiovascular disease risk. Apple polyphenols may contribute to explain these effects. Endothelial dysfunction has been associated with early stage of atherosclerosis and polyphenols from various dietary sources have been shown to reverse it. The aim of the present study was to investigate the effect of the consumption of a polyphenol-rich apple on endothelial function. SUBJECTS/METHODS: In all, 30 hypercholesterolemic volunteers were included in a double-blind, randomized crossover trial. They successively consumed 40 g of two lyophilized apples, polyphenol-rich and polyphenol-poor, providing respectively 1.43 and 0.21 g polyphenols per day during two 4-week periods separated by a 4-week washout period. RESULTS: Brachial artery flow-mediated vasodilation (FMD) was assessed at the beginning and at the end of each intervention period. FMD did not differ between the polyphenol-rich and the polyphenol-poor apples, neither did the other cardiovascular disease risk factors (plasma lipids, homocysteine, antioxidant capacity). CONCLUSIONS: These data suggest that over a 4-week period, the consumption of a polyphenol-rich apple does not improve vascular function in hypercholesterolemic patients.

DNA aptamers against the MUC1 tumour marker: design of aptamer-antibody sandwich ELISA for the early diagnosis of epithelial tumours.

Aptamers are functional molecules able to bind tightly and selectively to disease markers, offering great potential for applications in disease diagnosis and therapy. MUC1 is a well-known tumour marker present in epithelial malignancies and is used in immunotherapeutic and diagnostic approaches. We report the selection of DNA aptamers that bind with high affinity and selectivity an MUC1 recombinant protein containing five repeats of the variable tandem repeat region. Aptamers were selected using the SELEX methodology from an initial library containing a 25-base-long variable region for their ability to bind to the unglycosylated form of the MUC1 protein. After ten rounds of in vitro selection and amplification, more than 90% of the pool of sequences consisted of target-binding molecules, which were cloned, sequenced and found to share no sequence consensus. The binding properties of these aptamers were quantified using ELISA and surface plasmon resonance. The lead aptamer sequence was subsequently used in the design of an aptamer-antibody hybrid sandwich ELISA for the identification and quantification of MUC1 in buffered solutions. Following optimisation of the operating conditions, the resulting enzyme immunoassay displayed an EC50 value of 25 microg/ml, a detection limit of 1 microg/ml and a linear range between 8 and 100 microg/ml for the MUC1 five tandem repeat analyte. In addition, recovery studies performed in buffer conditions resulted in averaged recoveries between 98.2 and 101.7% for all spiked samples, demonstrating the usability of the aptamer as a receptor in microtitre-based assays. Our results aim towards the formation of new diagnostic assays against this tumour marker for the early diagnosis of primary or metastatic disease in breast, bladder and other epithelial tumours.

Respiratory rhythms generated in the lamprey rhombencephalon.

Brainstem networks generating the respiratory rhythm in lampreys are still not fully characterized. In this study, we described the patterns of respiratory activities and we identified the general location of underlying neural networks. In a semi-intact preparation including the brain and gills, rhythmic discharges were recorded bilaterally with surface electrodes placed over the vagal motoneurons. The main respiratory output driving rhythmic gill movements consisted of short bursts (40.9+/-15.6 ms) of discharge occurring at a frequency of 1.0+/-0.3 Hz. This fast pattern was interrupted by long bursts (506.3+/-174.6 ms) recurring with an average period of 37.4+/-24.9 s. After isolating the brainstem by cutting all cranial nerves, the frequency of the short respiratory bursts did not change significantly, but the slow pattern was less frequent. Local injections of a glutamate agonist (AMPA) and antagonists (6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) or D,L-amino-5-phosphonopentanoic acid (AP5)) were made over different brainstem regions to influence respiratory output. The results were similar in the semi-intact and isolated-brainstem preparations. Unilateral injection of AP5 or CNQX over a rostral rhombencephalic region, lateral to the rostral pole of the trigeminal motor nucleus, decreased the frequency of the fast respiratory rhythm bilaterally or stopped it altogether. Injection of AMPA at the same site increased the rate of the fast respiratory rhythm and decreased the frequency of the slow pattern. The activity recorded in this area was synchronous with that recorded over the vagal motoneurons. After a complete transverse lesion of the brainstem caudal to the trigeminal motor nucleus, the fast rhythm was confined to the rostral area, while only the slow activity persisted in the vagal motoneurons. Our results support the hypothesis that normal breathing depends on the activity of neurons located in the rostral rhombencephalon in lampreys, whereas the caudal rhombencephalon generates the slow pattern.

Cell-surface proteoglycans as molecular portals for cationic peptide and polymer entry into cells.

Polycationic macromolecules and cationic peptides acting as PTDs (protein transduction domains) and CPPs (cell-penetrating peptides) represent important classes of agents used for the import and delivery of a wide range of molecular cargoes into cells. Their entry into cells is typically initiated through interaction with cell-surface HS (heparan sulfate) molecules via electrostatic interactions, followed by endocytosis of the resulting complexes. However, the endocytic mechanism employed (clathrin-mediated endocytosis, caveolar uptake or macropinocytosis), defining the migration of these peptides into cells, depends on parameters such as the nature of the cationic agent itself and complex formation with cargo, as well as the nature and distribution of proteoglycans expressed on the cell surface. Moreover, a survey of the literature suggests that endocytic pathways should not be considered as mutually exclusive, as more than one entry mechanism may be operational for a given cationic complex in a particular cell type. Specifically, the observed import may best be explained by the distribution and uptake of cell-surface HSPGs (heparan sulfate proteoglycans), such as syndecans and glypicans, which have been shown to mediate the uptake of many ligands besides cationic polymers. A brief overview of the roles of HSPGs in ligand internalization is presented, as well as mechanistic hypotheses based on the known properties of these cell-surface markers. The identification and investigation of interactions made by glycosaminoglycans and core proteins of HSPGs with PTDs and cationic polymers will be crucial in defining their uptake by cells.

Increased prevalence of subclinical atherosclerosis in patients with small-vessel vasculitis.

BACKGROUND AND OBJECTIVE: Although changes in smaller vessels is the hallmark of medium-sized and small-vessel vasculitis, it has been suggested that large arteries of such patients may also be affected by the early atherosclerotic process because of coexisting risk factors or systemic inflammation. This study aimed to bring additional arguments supporting this hypothesis. DESIGN, SETTING AND PATIENTS: 50 consecutive patients with primary systemic necrotising vasculitis and 100 controls matched for age and sex underwent ultrasonic detection of plaque in three peripheral vessels (carotid and femoral arteries and abdominal aorta). Cardiovascular risk factors and inflammation (C reactive protein (CRP)) were concomitantly measured in all participants, and diagnosis of high-risk status was defined by the presence of known history of cardiovascular disease, type 2 diabetes or 10-year-Framingham Risk Score > or =20%. RESULTS: Patients had higher frequency of plaque than controls in the carotid arteries (p<0.05), in the aorta (p<0.01) and in the three vessels examined (p<0.001), and adjustment for high-risk status did not confound such difference in the aorta and in the three vessels. In the overall population of patients and controls, vasculitis was associated with a higher frequency of three-vessel plaques (p<0.05), independently of high-risk status and CRP. In patients, the higher frequency of three-vessel plaques was associated with high-risk status (p<0.05) but not with CRP, or disease and treatment characteristics. CONCLUSIONS: Small-vessel vasculitis is associated with more frequent subclinical atherosclerosis, especially extended to multiple peripheral vessels, and such association is not entirely explained by cardiovascular risk factors and systemic inflammation.

Modulation of respiratory activity by locomotion in lampreys.

In vertebrates, locomotion is associated with changes in respiratory activity, but the neural mechanisms by which this occurs remain unknown. We began examining this in lampreys using a semi-intact preparation of young adult Petromyzon marinus, in which respiratory and locomotor behaviors can be recorded simultaneously with the activity of the underlying neural control systems. Spontaneous fictive respiration was recorded with suction electrodes positioned over the glossopharyngeal or the rostral vagal motor nucleus. In this preparation, locomotor activity, characterized by symmetrical tail movements (electromyogram recordings), was evoked by mechanical stimulation of the skin. During locomotion, the mean respiratory frequency and the mean area of the motor bursts were significantly increased (81.6+/-28.6% and 62.8+/-25.4%, respectively; P<0.05). The frequency returned to normal 92+/-51 s after the end of locomotion. There were fluctuations in the instantaneous respiratory and locomotor frequencies that were rhythmical but antiphasic for the two rhythmic activities. The changes in respiratory activity were also examined during bouts of locomotion occurring spontaneously, and it was found that a modification in respiratory activity preceded the onset of spontaneous locomotion by 3.5+/-2.6 s. This suggests that the early respiratory changes are anticipatory and are not caused by feedback generated by locomotion. The increase in respiratory frequency during locomotion induced by sensory stimulation persisted after removal of the mesencephalon. When both the mesencephalon and spinal cord were removed, resulting in the isolation of the rhombencephalon, changes in the respiratory activity were also present following skin stimulations that would have normally induced locomotion. Altogether, the results suggest that respiratory changes are programmed to adjust ventilation prior to motor activity, and that a central rhombencephalic mechanism is involved.

Gender differences in wall shear-mediated brachial artery vasoconstriction and vasodilation.

OBJECTIVES: We sought to investigate wall shear rate (WSR) and brachial artery diameter (BAD) changes simultaneously and to determine whether any gender differences exist in arterial reactivity. BACKGROUND: Wall shear rate/stress and arterial reactivity are rarely assessed at the same time. Furthermore, flow-mediated vasoconstriction has received less attention than flow-mediated vasodilation in humans. METHODS: A new noninvasive evaluation of WSR in the brachial artery, using multigated, pulsed Doppler velocimeter and a double-transducer probe moved and fixed by a robotic system, was developed. RESULTS: The validity of the system was tested in vitro with calibrated tubes and showed a high correlation (r = 0.98, p < 0.001). In 10 men and 10 women of similar age, induction of low and high shear rates by forearm occlusion produced significant vasoconstriction and vasodilation, respectively. The time lag for maximal BAD changes was 3 min for vasoconstriction and 1 min for vasodilation. A greater half-time for vasodilation (96 +/- 6 for men and 86 +/- 12 s for women) than for shear rate (31 +/- 5 s for men and 34 +/- 4 s for women) was observed after discontinuation of occlusion. Relative BAD was correlated with WSR changes, showing a significantly higher slope in women than in men (p < 0.01). Moreover, a larger normalized arterial diameter per shear rate was observed for vasoconstriction (p < 0.01) and vasodilation (p < 0.01) in women than in men. CONCLUSIONS: Shear-mediated arterial vasodilation and vasoconstriction were more pronounced in women than in men, suggesting different gender-related sensitivity in the regulation of large-artery vascular tone.

Erythrocyte, but not plasma, vitamin E concentration is associated with carotid intima-media thickening in asymptomatic men at risk for cardiovascular disease.

Epidemiological data regarding the preventive role of vitamin E in the pathogenesis of atherosclerosis have yielded conflicting results, possibly because endpoints considered were clinical events but not detection of atherosclerosis per se. Otherwise, it has been suggested that the measure of the erythrocyte alpha-tocopherol level may be more suitable to assess the human tocopherol status than its plasma level. We investigated the association between early atherosclerosis in superficial arteries assessed noninvasively and the alpha-tocopherol status in 261 asymptomatic men at risk for cardiovascular disease. alpha-Tocopherol concentrations in plasma, HDL, and erythrocytes were determined using a reverse-phase HPLC method. Detection of carotid plaques and measure of carotid intima-media thickness (IMT) were performed using high-resolution B-mode ultrasonography. The main result of this study is the observation of a negative correlation (P<0.01) between carotid IMT and erythrocyte alpha-tocopherol concentration, independently of conventional cardiovascular risk factors, whereas no such association has been found with plasma (total or HDL) alpha-tocopherol concentrations. No association has been evidenced between alpha-tocopherol concentrations and carotid plaques. These results emphasize the primary protective role of vitamin E in the early phases of atherosclerosis and the significance of the erythrocyte alpha-tocopherol concentration as a marker of atherosclerosis.

Arteriovenous malformation of the mandible: embolization and direct injection therapy.

Arteriovenous malformation (AVM) of the mandible is a rare entity but one that can be potentially fatal as a result of massive hemorrhage. Traditional treatment involved extensive surgical resection of the mandible. With the advent of improved endovascular techniques, interventional radiology is now the best method to control active hemorrhage and ultimately cure these lesions. The authors describe three cases of successfully treated mandibular AVM by percutaneous and/or endovascular techniques.

Difference in carotid artery wall structure between Swedish and French men at low and high coronary risk.

BACKGROUND AND PURPOSE: We attempted to detect a group-specific north-south difference in carotid artery intima-media thickness (IMT), a marker of subsequent cardiovascular complication, by means of a case (high risk)-control (low risk) study in French and Swedish men. METHODS: The selection of high-risk and low-risk subjects was performed within the lower and upper percentiles of the Framingham risk distribution of 2 samples of 1000 white, male auto workers (45 to 50 years of age) in France (Renault) and Sweden (Volvo). In total, 299 men at low risk (79 French, 76 Swedish) and high risk (61 French, 83 Swedish), free from sustained hypertension, definite hypercholesterolemia, and cardiovascular disease, were included. Both common carotid arteries, by ultrasonography and central off-line computerized analysis, provided measurements of far wall media thickness, lumen diameter, and cross-sectional area IMT (CSA-IMT). RESULTS: As compared with low-risk status, high-risk status was associated with higher IMT (P<0.001), diameter (P<0.01), and CSA-IMT (P<0.001) in French men and higher CSA-IMT (P<0.05) in Swedish men. IMT, diameter, and CSA-IMT were higher in Swedish than in French men in the low-risk group (P<0.001) and in the high-risk group (P<0.01, P<0.001, P<0.001). The multivariate analysis of the whole population showed that IMT, diameter, and CSA-IMT were associated with risk status (P<0.01, P<0.01, P<0.001) and geographic status (P<0.001). CONCLUSIONS: These findings show that the geographic status influences carotid artery structure independent of traditional cardiovascular risk factors and that this may affect the mortality and morbidity gradient between Northern and Southern Europe.

Maternal prenatal, postpartum, and concurrent stressors and temperament in 3-year-olds: a person and variable analysis.

The study was based on the assumption that stressors in the lives of pregnant and parenting women are processes that affect prenatal, postpartum, and concurrent maternal hormones and emotions and that these processes affect child temperament. The hypotheses were tested in a group of 67 young mothers and their 3-year-old children. Mothers were clustered into groups based on longitudinal patterns of hormones and emotions at prenatal, postpartum. and 3-year follow-up assessments. The analyses focused on relating maternal patterns of hormones and emotions to the child's temperament at age 3 years. Temperament was assessed by questionnaire and observation of behavior during a challenging situation. Illustrative findings included the following. Verbal aggression and nonverbal aggression were significantly higher in children of mothers in the low prenatal hormone cluster than children of mothers in the high prenatal hormone cluster. Children of mothers in the postpartum low testosterone (T), estradiol (E2), and androstenedione (delta4-A) and medium cortisol (Cort) cluster (mainly low hormone cluster) exhibited significantly more physical aggression than children of mothers in the medium T and A4-A, high E2 and low Cort cluster. Maternal patterns of hormones, emotions, and parenting attitudes and practices were related to multiple aspects of temperament when the children were age 3 years. The findings support the important role of maternal biological and psychological processes in the development of child temperament.

Differential effects of nifedipine and co-amilozide on the progression of early carotid wall changes.

BACKGROUND: Common carotid artery intima-media thickness (IMT) progression was compared between 4 years of treatment with nifedipine and diuretic. METHODS AND RESULTS: This study, ancillary to the International Nifedipine GITS Study: Intervention as a Goal in Hypertension Treatment (INSIGHT), involved nifedipine 30 mg or co-amilozide (hydrochlorothiazide 25 mg and amiloride 2.5 mg) with optional subsequent titration. Among 439 randomized hypertensive patients, 324 had >/=1 year of follow-up (intent-to-treat group), and 242 completed follow-up (until-end-of-study group). Ultrasonography was performed at baseline, 4 months later, and then every year. Central computerized reading provided far-wall IMT, diameter, and cross-sectional area IMT (CSA-IMT). The primary outcome was IMT progression rate (slope of IMT-time regression). Secondary outcomes were changes from baseline (Delta) in IMT, diameter, and CSA-IMT. In the until-end-of-study population, between-treatment differences existed in IMT progression rate (P=0.002), Delta IMT (P=0.001), and Delta CSA-IMT (P=0.006), because IMT progressed on co-amilozide but not on nifedipine. In the intent-to-treat population, treatment differences existed in Delta IMT (P=0.004) and Delta CSA-IMT (P=0.04) but not in IMT progression rate (P=0.09). Patients with >/=2, 3, or 4 years of follow-up showed treatment differences in IMT progression rate (P=0.04, 0.004, 0.007, respectively), Delta IMT (P=0.005, 0.001, 0.005), and Delta CSA-IMT (P=0.025, 0.013, 0.015). Diameter decreased more on co-amilozide than on nifedipine in the intent-to-treat population (P<0.05), whereas blood pressure decreased similarly on both treatments. CONCLUSIONS: A difference in early carotid wall changes is shown between 2 equally effective antihypertensive treatments.

Association studies between haemochromatosis gene mutations and the risk of cardiovascular diseases.

BACKGROUND: Haemochromatosis is a common genetic disorder, inherited as an autosomal recessive trait that results in a progressive accumulation of iron in most tissues of the body. Positive association studies have been recently published between cardiovascular diseases and heterozygosity for the major mutation C282Y in the haemochromatosis gene HFE. METHODS: In the present work, we have determined the HFE genotypes for C282Y and H63D in subjects from two case-control studies: the ECTIM and GENIC studies, designed to identify genetic variants associated with myocardial and brain infarction, respectively. In addition, we tested whether HFE mutations were associated with the degree of arteriosclerosis assessed non-invasively by Doppler ultrasonography on the carotid and femoral arteries, in a group of apparently healthy individuals (the AXA Study). RESULTS: The prevalence of 282Y, and 63D allele carriers, did not differ between cases and controls in the ECTIM and in the GENIC studies, while 63D but not 282Y carriers were more numerous among subjects with atherosclerotic plaques in the AXA Study. CONCLUSIONS: These three studies do not provide consistent evidence supporting the hypothesis that HFE mutations are associated with an increased risk of cardiovascular disease and with the development of arteriosclerosis.

The use of Shiga-like toxin 1 in cancer therapy.

The ribosome-inactivating protein, Shiga-like toxin-1 (SLT-1, SLT-I, Verotoxin 1, VT1) targets cells that express the glycolipid globotriaosylceramide (CD77) on their surface. The frequent occurrence of SLT-1 receptors on tumor cells derived from patients with hematological cancers (follicular lymphoma, multiple myeloma, chronic lymphocytic leukemia) and their absence on human CD34(+) hematopoietic stem cells suggest the ex vivo use of Shiga-like toxin-1 in purging CD77(+) tumor cells from autologous stem cell transplants. SLT-1 receptors are also commonly expressed on breast cancer, ovarian cancer and astrocytoma cells. In particular, the sensitivity of astrocytoma cell lines to this toxin provides an opportunity for using SLT-1 in vivo in the context of treating patients afflicted by this common form of brain tumor. Finally, the known structural features of SLT-1 allow one to contemplate altering its receptor specificity in an effort to target CD77(-) tumor cell populations.

Probing the surface of eukaryotic cells using combinatorial toxin libraries.

The success of proteomics hinges in part on the development of approaches able to map receptors on the surface of cells. One strategy to probe a cell surface for the presence of internalized markers is to make use of Shiga-like toxin 1 (SLT-1), a ribosome-inactivating protein that kills eukaryotic cells [1, 2]. SLT-1 binds to the glycolipid globotriaosylceramide [3, 4], which acts as a shuttle, allowing the toxin to be imported and routed near ribosomes. We investigated the use of SLT-1 as a structural template to create combinatorial libraries of toxin variants with altered receptor specificity. Since all SLT-1 variants retain their toxic function, this property served as a search engine enabling us to identify mutants from these libraries able to kill target cells expressing internalizable receptors. Random mutations were introduced in two discontinuous loop regions of the SLT-1 receptor binding subunit. Minimal searches from screening 600 bacterial colonies randomly picked from an SLT-1 library identified toxin mutants able to kill cell lines resistant to the wild-type toxin. One such mutant toxin was shown to bind to a new receptor on these cell lines by flow cytometry. Toxin libraries provide a strategy to delineate the spectrum of receptors on eukaryotic cells.

Vectorial delivery of macromolecules into cells using peptide-based vehicles.

The ability to direct the import of therapeutic agents into cells and target them to specific organelles would greatly enhance their functional efficacy. The available spectrum of peptide-based import signals and intracellular routing signals might provide practical solutions towards achieving a guided or vectorial delivery of molecules. Multiple cell-targeting signals and routing domains can be efficiently displayed on branched peptides. These constructs are typically nonimmunogenic in the absence of adjuvant and can be easily assembled using solid phase synthesis. The vectorial delivery of larger complexes, however, will necessitate the development of alternate templates that favor the optimal presentation of all functional signals.

Localization of chromophore absorption signals in TEM with an improved prism-mirror-prism filter.

A corrected prism-mirror-prism electron energy filter with curved entrance and exit faces was designed and incorporated into a Zeiss EM902 transmission electron microscope. The installation of the new filter required little modification to the existing microscope geometry and electronics. The filter had an energy resolution of 1.1 eV over the full image plane (acceptance half angle 10 mradian). The improved energy resolution was applied in studies of the low electron energy loss region that includes molecular orbital excitations or chromophore energy absorptions. Chromophore signal behaviour under electron irradiation was characterized using embedded crystals of hematin and of the dye mercury orange. Images of these crystals confirmed the expected decrease in signal intensity on shifting the selected energy loss from the region of molecular orbital excitations (less than approximately 5 eV) to higher energy losses. Electron irradiation-induced fading of the chromophore signal from hematin and mercury orange yielded similar 1/e dose values of 1.1 x 10(5) e(-) nm(-2) and 1.4 x 10(5) e(-) nm(-2) respectively. In a cellular context, chromophore signals were obtained from energy-filtered images of RIF-1 cell sections containing the photosensitizer chlorin e6 and from sections of BS-C-1 cells with cytoskeletal labelling via FITC-conjugated antibodies. The respective signals were extracted using a dose-dependent method or a shift in selected energy. Chromophore signal distributions were in agreement with fluorescence light microscopic images, but provided detail at higher spatial resolution.

Polymorphisms of the human matrix gla protein (MGP) gene, vascular calcification, and myocardial infarction.

The matrix Gla protein (MGP) is an important inhibitor of vessel and cartilage calcification that is strongly expressed in human calcified, atherosclerotic plaques and could modulate plaque calcification and coronary heart disease risk. Using a genetic approach, we explored this possibility by identifying polymorphisms of the MGP gene and testing their possible association with myocardial infarction (MI) and plaque calcification. Eight polymorphisms were identified in the coding and 5'-flanking sequences of the MGP gene. All polymorphisms were investigated in 607 patients with MI and 667 control subjects recruited into the ECTIM Study (Etude Cas-Témoins de l'Infarctus du Myocarde) and in 717 healthy individuals with echographically assessed arterial calcification and atherosclerosis who were participating in the AXA Study. In the ECTIM Study, alleles and genotypes were distributed similarly in patients and controls in the whole study group; in only 1 subgroup of subjects defined as being at low risk for MI were the concordant A-7 and Ala 83 alleles more frequent in patients with MI than in controls (P<0.003). In the AXA Study among subjects with femoral atherosclerosis, the same alleles were more common in the presence than the absence of plaque calcification (P<0.025). The other MGP polymorphisms were not associated with any investigated clinical phenotype. Transient transfection experiments with allelic promoter-reporter gene constructs and DNA-protein interaction assays were carried out to assess possible in vitro functionality of the promoter variants detected at positions -814, -138, and -7 relative to the start of transcription. When compared with the -138 T allele, the minor -138 C: allele consistently conferred a reduced promoter activity of -20% (P<0.0001) in rat vascular smooth muscle cells and of -50% (P<0.004) in a human fibroblast cell line, whereas the other polymorphisms, including -7, displayed no evidence of in vitro functionality. We conclude that the A-7 or Ala 83 alleles of the MGP gene may confer an increased risk of plaque calcification and MI; however, the observed relationships are weak or limited to subgroups of patients and therefore need confirmation.

Gender difference in the influence of smoking on arterial wall thickness.

BACKGROUND: We hypothesized that arterial wall thickening, an early atherogenic alteration, might be associated with smoking differently according to gender, considering the cardiovascular protection of female sex hormones. METHODS AND RESULTS: We measured ultrasonographically carotid and femoral intima-media thickness (IMT) in 194 men and 330 women without risk factors other than smoking. In men: (i) current smokers had greater carotid and femoral IMT (P<0.01, P<0.001) and former smokers had greater femoral IMT (P<0.01) than never smokers; (ii) in pooled never, current and former smokers carotid and femoral IMT correlated to current daily smoking (P<0.01) and lifelong smoking (P<0.001); and (iii) carotid and femoral IMT correlated to age in never smokers (P<0.001), current smokers (P<0.01, P<0.001) and former smokers (P<0.01), with greater slopes in current than in former smokers at carotid site (P<0.05) and in current than in never smokers at femoral site (P<0.05). In women: (i) IMT did not differ by smoking status; (ii) in pooled smokers and non smokers femoral IMT correlated to current daily smoking (P=0.01) and to lifelong smoking (P<0.01) with a lower slope than in men (P<0.001), while carotid IMT did not; and (iii) carotid and femoral IMT correlated to age in never smokers (P<0.001), current smokers (P<0.001, P<0.05) and former smokers (P<0.001, P<0.01) with no different slopes. CONCLUSION: Smoking-related increase in IMT existed in men but not in women, suggesting a possible protection of female gender from early structural arterial alteration of smoking.