955 resultados para Low-density lipoprotein receptors
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Objective: We investigated the effect of advanced glycated albumin (AGE-albumin) on macrophage sensitivity to inflammation elicited by S100B calgranulin and lipopolysaccharide (LPS) and the mechanism by which HDL modulates this response. We also measured the influence of the culture medium, isolated from macrophages treated with AGE-albumin, on reverse cholesterol transport (RCT). Methods and results: Macrophages were incubated with control (C) or AGE-albumin in the presence or absence of HDL, followed by incubations with S100B or LPS. Also, culture medium obtained from cells treated with C- or AGE-albumin, following S100B or LPS stimulation was utilized to treat naive macrophages in order to evaluate cholesterol efflux and the expression of HDL receptors. In comparison with C-albumin, AGE-albumin, promoted a greater secretion of cytokines after stimulation with S100B or LPS. A greater amount of cytokines was also produced by macrophages treated with AGE-albumin even in the presence of HDL Cytokine-enriched medium, drawn from incubations with AGE-albumin and S100B or LPS impaired the cholesterol efflux mediated by apoA-I (23% and 37%, respectively), HDL2 (43% and 47%, respectively) and HDL3 (20% and 8.5%, respectively) and reduced ABCA-1 protein level (16% and 26%, respectively). Conclusions: AGE-albumin primes macrophages for an inflammatory response impairing the RCT. Moreover, AGE-albumin abrogates the anti-inflammatory role of HDL, which may aggravate the development of atherosclerosis in DM. (C) 2012 Elsevier BM. All rights reserved.
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Apolipoprotein J (ApoJ) ist ein heterodimeres sekretiertes Glycoprotein, welchem sowohl antiapoptotische als auch antiinflammatorische Eigenschaften zugeschrieben werden. Es wird unter vielen pathophysiologischen Zuständen verstärkt exprimiert. Dazu zählen viele Krankheiten wie z.B. Krebs, M. Alzheimer, Creuzfeldt Jakob und Atherosklerose. Die vorliegende Arbeit befasst sich zum Einen mit der Funktion von ApoJ bei Atherosklerose und zum Anderen mit der Regulation von ApoJ durch in atherosklerotischen Läsionen vorkommende Bestandteile. Für die Untersuchungen der Funktion von ApoJ bei der Atherosklerose wurde die „Mainzer Hypothese“ zugrunde gelegt, die davon ausgeht, dass enzymatisch verdautes LDL (high density lipoprotein) (E-LDL) ursächlich für die Entstehung von atherosklerotischen Läsionen ist. In der vorliegenden Arbeit konnte gezeigt werden, dass ApoJ zwar an E-LDL bindet, nicht aber an natives LDL und dass durch diese Bindung die zytotoxische Wirkung von E-LDL auf glatte Muskelzellen der Ratte unterdrückt wird. Mittels Annexinfärbung und Caspase-Messung konnte gezeigt werden, dass ApoJ in diesem Fall eine antiapoptotische Funktion aufweist. Durch immunhistochemische Untersuchungen an humanen Gewebsschnitten aus frühen atherosklerotischen Läsionen konnte eine Kolokalisation von ApoJ und E-LDL nachgewiesen werden. Diese Ergebnisse unterstreichen die Mainzer Hypothese. Durch eine Behandlung von glatten Muskelzellen der Ratte mit den Lipoproteinen LDL/E-LDL und nekrotischen Zellen sollte die Regulation von ApoJ durch in atherosklerotischen Läsionen vorhandenen Stimuli untersucht werden. Frühere Arbeiten unserer Arbeitsgruppe konnten bereits zeigen, dass eine Behandlung mit nekrotischen Zellen zu einer vermehrten Expression der ApoJ-mRNA führt und dass diese Regulation in Korrelation mit der Expression von Toll-like Rezeptoren (TLR) der verschiedenen Zellen steht. In dieser Arbeit konnte RNA aus nekrotischen Zellen als ApoJ-induzierende Komponente identifiziert werden. Durch Inhibition der TLR3-Signalwege konnten erste Hinweise darüber gewonnen werden, über welche Signaltransduktionswege die ApoJ Regulation erfolgt. Eine Behandlung der Zellen mit E LDL und LDL hingegen führte zu einer Repression der ApoJ-Sekretion. Diese Ergebnisse deuten darauf hin, dass in atherosklerotischen Läsionen sowohl ApoJ induzierende wie auch repremierende Stimuli vorhanden sind.
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OBJECTIVE: Metabolic changes caused by antiretroviral therapy (ART) may increase the risk of coronary heart disease (CHD). We evaluated changes in the prevalence of cardiovascular risk factors (CVRFs) and 10-year risk of CHD in a large cohort of HIV-infected individuals. METHODS: All individuals from the Swiss HIV Cohort Study (SHCS) who completed at least one CVRF questionnaire and for whom laboratory data were available for the period February 2000 to February 2006 were included in the analysis. The presence of a risk factor was determined using cut-offs based on the guidelines of the National Cholesterol Education Program (NCEP ATP III), the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7), the American Diabetes Association, and the Swiss Society for Cardiology. RESULTS: Overall, 8,033 individuals completed at least one CVRF questionnaire. The most common CVRFs in the first completed questionnaire were smoking (57.0%), low high-density lipoprotein (HDL) cholesterol (37.2%), high triglycerides (35.7%), and high blood pressure (26.1%). In total, 2.7 and 13.8% of patients were categorized as being at high (>20%) and moderate (10-20%) 10-year risk for CHD, respectively. Over 6 years the percentage of smokers decreased from 61.4 to 47.6% and the percentage of individuals with total cholesterol >6.2 mmol/L decreased from 21.1 to 12.3%. The prevalence of CVRFs and CHD risk was higher in patients currently on ART than in either pretreated or ART-naive patients. CONCLUSION: During the 6-year observation period, the prevalence of CVRFs remains high in the SHCS. Time trends indicate a decrease in the percentage of smokers and individuals with high cholesterol.
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BACKGROUND: HIV-1 infected individuals have an increased cardiovascular risk which is partially mediated by dyslipidemia. Single nucleotide polymorphisms in multiple genes involved in lipid transport and metabolism are presumed to modulate the risk of dyslipidemia in response to antiretroviral therapy. METHODS: The contribution to dyslipidemia of 20 selected single nucleotide polymorphisms of 13 genes reported in the literature to be associated with plasma lipid levels (ABCA1, ADRB2, APOA5, APOC3, APOE, CETP, LIPC, LIPG, LPL, MDR1, MTP, SCARB1, and TNF) was assessed by longitudinally modeling more than 4400 plasma lipid determinations in 438 antiretroviral therapy-treated participants during a median period of 4.8 years. An exploratory genetic score was tested that takes into account the cumulative contribution of multiple gene variants to plasma lipids. RESULTS: Variants of ABCA1, APOA5, APOC3, APOE, and CETP contributed to plasma triglyceride levels, particularly in the setting of ritonavir-containing antiretroviral therapy. Variants of APOA5 and CETP contributed to high-density lipoprotein-cholesterol levels. Variants of CETP and LIPG contributed to non-high-density lipoprotein-cholesterol levels, a finding not reported previously. Sustained hypertriglyceridemia and low high-density lipoprotein-cholesterol during the study period was significantly associated with the genetic score. CONCLUSIONS: Single nucleotide polymorphisms of ABCA1, APOA5, APOC3, APOE, and CETP contribute to plasma triglyceride and high-density lipoprotein-cholesterol levels during antiretroviral therapy exposure. Genetic profiling may contribute to the identification of patients at risk for antiretroviral therapy-related dyslipidemia.
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G protein-coupled receptors (GPCRs) are seven transmembrane domain proteins that transduce extracellular signals across the plasma membrane and couple to the heterotrimeric family of G proteins. Like most intrinsic membrane proteins, GPCRs are capable of oligomerization, the function of which has only been established for a few different receptor systems. One challenge in understanding the function of oligomers relates to the inability to separate monomeric and oligomeric receptor complexes in membrane environments. Here we report the reconstitution of bovine rhodopsin, a GPCR expressed in the retina, into an apolipoprotein A-I phospholipid particle, derived from high density lipoprotein (HDL). We demonstrate that rhodopsin, when incorporated into these 10 nm reconstituted HDL (rHDL) particles, is monomeric and functional. Rhodopsin.rHDL maintains the appropriate spectral properties with respect to photoactivation and formation of the active form, metarhodopsin II. Additionally, the kinetics of metarhodopsin II decay is similar between rhodopsin in native membranes and rhodopsin in rHDL particles. Photoactivation of monomeric rhodopsin.rHDL also results in the rapid activation of transducin, at a rate that is comparable with that found in native rod outer segments and 20-fold faster than rhodopsin in detergent micelles. These data suggest that monomeric rhodopsin is the minimal functional unit in G protein activation and that oligomerization is not absolutely required for this process.
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Lipoproteins are a heterogeneous population of blood plasma particles composed of apolipoproteins and lipids. Lipoproteins transport exogenous and endogenous triglycerides and cholesterol from sites of absorption and formation to sites of storage and usage. Three major classes of lipoproteins are distinguished according to their density: high-density (HDL), low-density (LDL) and very low-density lipoproteins (VLDL). While HDLs contain mainly apolipoproteins of lower molecular weight, the two other classes contain apolipoprotein B and apolipoprotein (a) together with triglycerides and cholesterol. HDL concentrations were found to be inversely related to coronary heart disease and LDL/VLDL concentrations directly related. Although many studies have been published in this area, few have concentrated on the exact protein composition of lipoprotein particles. Lipoproteins were separated by density gradient ultracentrifugation into different subclasses. Native gel electrophoresis revealed different gel migration behaviour of the particles, with less dense particles having higher apparent hydrodynamic radii than denser particles. Apolipoprotein composition profiles were measured by matrix-assisted laser desorption/ionization-mass spectrometry on a macromizer instrument, equipped with the recently introduced cryodetector technology, and revealed differences in apolipoprotein composition between HDL subclasses. By combining these profiles with protein identifications from native and denaturing polyacrylamide gels by liquid chromatography-tandem mass spectrometry, we characterized comprehensively the exact protein composition of different lipoprotein particles. We concluded that the differential display of protein weight information acquired by macromizer mass spectrometry is an excellent tool for revealing structural variations of different lipoprotein particles, and hence the foundation is laid for the screening of cardiovascular disease risk factors associated with lipoproteins.
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We have shown that liposomal amphotericin B (L-AmpB) decreased renal toxicity and maintains the antifungal activity of amphotericin B (AmpB). We have also observed that L-AmpB is predominantly associated with high density lipoproteins (HDL) as compared to Fungizone (AmpB + deoxycholate). The present experiments were designed to assess the biological relevance of transferring AmpB to HDL. We observed that AmpB was less toxic to kidney cells when associated with HDL, however AmpB toxicity was maintained when associated with LDL. To further understand how HDL-associated AmpB reduces renal cell toxicity the presence of HDL and LDL receptors in this cell line was determined. We observed that these cells expressed high and low affinity LDL receptors, but only low affinity HDL receptors. The reduced renal cell toxicity of HDL-associated AmpB may be due to its lack of interaction with renal cells because of the absence of HDL receptors. Since AmpB interacts with cholesteryl esters whose transfer among lipoproteins is regulated by Lipid transfer Protein (LTP), the role of LTP on the distribution of AmpB to HDL and LDL was next examined. We found that negatively charged liposomes significantly reduced LTP-mediated transfer of CE between HDL and LDL, independent of the presence of AmpB, while Fungizone only significantly inhibited CE transfer at one concentration tested (20$\mu$g/ml). Therefore, we believe that the decreased renal toxicity of L-AmpB is related to its predominant distribution to HDL which is regulated by the inhibition of LTP activity. ^
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Growing cells are continuously processing signals of all varieties and responding to these signals by changes in cellular gene expression. One signal that cells in close proximity relay to each other is cell-cell contact. Non-transformed cells respond to cell-cell contact by arrest of growth and entry into G$\sb0,$ a process known as contact inhibition. Transformed cells do not respond to contact inhibition and continue to grow to high cell density, forming foci when in cell culture and tumors in the living organism. The events surrounding the generation, transduction, and response to cellular contact are poorly understood. In the present study, a novel gene product, drp, is shown to be expressed at high levels in cultured cells at high cell density. This density regulated protein, drp, has an apparent molecular weight of 70 kDa. Northern analysis shows drp to be highly expressed in cardiac and skeletal muscle and least abundant in lung and kidney tissues. By homology to two independently derived sequence tagged sites (STSs) used in the human genome project, drp or a closely related sequence maps to human chromosome 12. Density-dependent increases in drp expression have been demonstrated in six different cell lines including NIH 3T3, Hela and a human teratocarcinoma cell line, PA-1. Cells exhibit increased drp expression both when they are plated at increasing concentrations per unit area, or plated at low density and allowed to grow naturally to higher cell density. Cells at high density can exhibit several phenotypes including growth arrest, accumulation of soluble factors in the media, and increased numbers of cell contacts. Growth arrest by serum starvation or TGF-$\beta$ treatment fails to produce an increase in drp expression. Similarly, treatment of low density cells with conditioned media from high density cells fails to elicit drp expression. These results argue that neither soluble factors accumulated or expressed at high density nor simple exit from the cell cycle is sufficient to produce an increase in drp expression. The expression of drp appears to be uniquely regulated by cell density alone. ^
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BACKGROUND AND PURPOSE Treatment with statins reduces the rate of cardiovascular events in high-risk patients, but residual risk persists. At least part of that risk may be attributable to atherogenic dyslipidemia characterized by low high-density lipoprotein cholesterol (≤40 mg/dL) and high triglycerides (triglycerides≥150 mg/dL). METHODS We studied subjects with stroke or transient ischemic attack in the Prevention of Cerebrovascular and Cardiovascular Events of Ischemic Origin With Terutroban in Patients With a History of Ischemic Stroke or Transient Ischemic Attack (PERFORM; n=19,100) and Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL; n=4731) trials who were treated with a statin and who had high-density lipoprotein cholesterol and triglycerides measurements 3 months after randomization (n=10,498 and 2900, respectively). The primary outcome measure for this exploratory analysis was the occurrence of major cardiovascular events (nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death). We also performed a time-varying analysis to account for all available high-density lipoprotein cholesterol and triglyceride measurements. RESULTS A total of 10% of subjects in PERFORM and 9% in SPARCL had atherogenic dyslipidemia after ≥3 months on start statin therapy. After a follow-up of 2.3 years (PERFORM) and 4.9 years (SPARCL), a major cardiovascular event occurred in 1123 and 485 patients in the 2 trials, respectively. The risk of major cardiovascular events was higher in subjects with versus those without atherogenic dyslipidemia in both PERFORM (hazard ratio, 1.36; 95% confidence interval, 1.14-1.63) and SPARCL (hazard ratio, 1.40; 95% confidence interval, 1.06-1.85). The association was attenuated after multivariable adjustment (hazard ratio, 1.23; 95% confidence interval, 1.03-1.48 in PERFORM and hazard ratio, 1.24; 95% confidence interval, 0.93-1.65 in SPARCL). Time-varying analysis confirmed these findings. CONCLUSIONS The presence of atherogenic dyslipidemia was associated with higher residual cardiovascular risk in PERFORM and SPARCL subjects with stroke or transient ischemic attack receiving statin therapy. Specific therapeutic interventions should now be trialed to address this residual risk.
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OBJECTIVES Bone replacement grafting materials play an important role in regenerative dentistry. Despite a large array of tested bone-grafting materials, little information is available comparing the effects of bone graft density on in vitro cell behavior. Therefore, the aim of the present study is to compare the effects of cells seeded on bone grafts at low and high density in vitro for osteoblast adhesion, proliferation, and differentiation. MATERIALS AND METHODS The response of osteoblasts to the presence of a growth factor (enamel matrix derivative, (EMD)) in combination with low (8 mg per well) or high (100 mg per well) bone grafts (BG; natural bone mineral, Bio-Oss®) density, was studied and compared for osteoblast cell adhesion, proliferation, and differentiation as assessed by real-time PCR. Standard tissue culture plastic was used as a control with and without EMD. RESULTS The present study demonstrates that in vitro testing of bone-grafting materials is largely influenced by bone graft seeding density. Osteoblast adhesion was up to 50 % lower when cells were seeded on high-density BG when compared to low-density BG and control tissue culture plastic. Furthermore, proliferation was affected in a similar manner whereby cell proliferation on high-density BG (100 mg/well) was significantly increased when compared to that on low-density BG (8 mg/well). In contrast, cell differentiation was significantly increased on high-density BG as assessed by real-time PCR for markers collagen 1 (Col 1), alkaline phosphatase (ALP), and osteocalcin (OC) as well as alizarin red staining. The effects of EMD on osteoblast adhesion, proliferation, and differentiation further demonstrated that the bone graft seeding density largely controls in vitro results. EMD significantly increased cell attachment only on high-density BG, whereas EMD was able to further stimulate cell proliferation and differentiation of osteoblasts on control culture plastic and low-density BG when compared to high-density BG. CONCLUSION The results from the present study demonstrate that the in vitro conditions largely influence cell behavior of osteoblasts seeded on bone grafts and in vitro testing. CLINICAL RELEVANCE These results also illustrate the necessity for careful selection of bone graft seeding density to optimize in vitro testing and provide the clinician with a more accurate description of the osteopromotive potential of bone grafts.
Inactive Matrix Gla-Protein Is Associated With Arterial Stiffness in an Adult Population-Based Study
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Increased pulse wave velocity (PWV) is a marker of aortic stiffness and an independent predictor of mortality. Matrix Gla-protein (MGP) is a vascular calcification inhibitor that needs vitamin K to be activated. Inactive MGP, known as desphospho-uncarboxylated MGP (dp-ucMGP), can be measured in plasma and has been associated with various cardiovascular markers, cardiovascular outcomes, and mortality. In this study, we hypothesized that high levels of dp-ucMGP are associated with increased PWV. We recruited participants via a multicenter family-based cross-sectional study in Switzerland. Dp-ucMGP was quantified in plasma by sandwich ELISA. Aortic PWV was determined by applanation tonometry using carotid and femoral pulse waveforms. Multiple regression analysis was performed to estimate associations between PWV and dp-ucMGP adjusting for age, renal function, and other cardiovascular risk factors. We included 1001 participants in our analyses (475 men and 526 women). Mean values were 7.87±2.10 m/s for PWV and 0.43±0.20 nmol/L for dp-ucMGP. PWV was positively associated with dp-ucMGP both before and after adjustment for sex, age, body mass index, height, systolic and diastolic blood pressure (BP), heart rate, renal function, low- and high-density lipoprotein, glucose, smoking status, diabetes mellitus, BP and cholesterol lowering drugs, and history of cardiovascular disease (P≤0.01). In conclusion, high levels of dp-ucMGP are independently and positively associated with arterial stiffness after adjustment for common cardiovascular risk factors, renal function, and age. Experimental studies are needed to determine whether vitamin K supplementation slows arterial stiffening by increasing MGP carboxylation.
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OBJECTIVE Renal resistive index (RRI) varies directly with renal vascular stiffness and pulse pressure. RRI correlates positively with arteriolosclerosis in damaged kidneys and predicts progressive renal dysfunction. Matrix Gla-protein (MGP) is a vascular calcification inhibitor that needs vitamin K to be activated. Inactive MGP, known as desphospho-uncarboxylated MGP (dp-ucMGP), can be measured in plasma and has been associated with various cardiovascular (CV) markers, CV outcomes and mortality. In this study we hypothesize that increased RRI is associated with high levels of dp-ucMGP. DESIGN AND METHOD We recruited participants via a multi-center family-based cross-sectional study in Switzerland exploring the role of genes and kidney hemodynamics in blood pressure regulation. Dp-ucMGP was quantified in plasma samples by sandwich ELISA. Renal doppler sonography was performed using a standardized protocol to measure RRIs on 3 segmental arteries in each kidney. The mean of the 6 measures was reported. Multiple regression analysis was performed to estimate associations between RRI and dp-ucMGP adjusting for sex, age, pulse pressure, mean pressure, renal function and other CV risk factors. RESULTS We included 1035 participants in our analyses. Mean values were 0.64 ± 0.06 for RRI and 0.44 ± 0.21 (nmol/L) for dp-ucMGP. RRI was positively associated with dp-ucMGP both before and after adjustment for sex, age, body mass index, pulse pressure, mean pressure, heart rate, renal function, low and high density lipoprotein, smoking status, diabetes, blood pressure and cholesterol lowering drugs, and history of CV disease (P < 0.001). CONCLUSIONS RRI is independently and positively associated with high levels of dp-ucMGP after adjustment for pulse pressure and common CV risk factors. Further studies are needed to determine if vitamin K supplementation can have a positive effect on renal vascular stiffness and kidney function.
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Apolipoprotein E (ApoE) plays a major role in the metabolism of high density and low density lipoproteins (HDL and LDL). Its common protein isoforms (E2, E3, E4) are risk factors for coronary artery disease (CAD) and explain between 16 to 23% of the inter-individual variation in plasma apoE levels. Linkage analysis has been completed for plasma apoE levels in the GENOA study (Genetic Epidemiology Network of Atherosclerosis). After stratification of the population by lipoprotein levels and body mass index (BMI) to create more homogeneity with regard to biological context for apoE levels, Hispanic families showed significant linkage on chromosome 17q for two strata (LOD=2.93 at 104 cM for a low cholesterol group, LOD=3.04 at 111 cM for a low cholesterol, high HDLC group). Replication of 17q linkage was observed for apoB and apoE levels in the unstratified Hispanic and African-American populations, and for apoE levels in African-American families. Replication of this 17q linkage in different populations and strata provides strong support for the presence of gene(s) in this region with significant roles in the determination of inter-individual variation in plasma apoE levels. Through a positional and functional candidate gene approach, ten genes were identified in the 17q linked region, and 62 polymorphisms in these genes were genotyped in the GENOA families. Association analysis was performed with FBAT, GEE, and variance-component based tests followed by conditional linkage analysis. Association studies with partial coverage of TagSNPs in the gene coding for apolipoprotein H (APOH) were performed, and significant results were found for 2 SNPs (APOH_20951 and APOH_05407) in the Hispanic low cholesterol strata accounting for 3.49% of the inter-individual variation in plasma apoE levels. Among the other candidate genes, we identified a haplotype block in the ACE1 gene that contains two major haplotypes associated with apoE levels as well as total cholesterol, apoB and LDLC levels in the unstratified Hispanic population. Identifying genes responsible for the remaining 60% of inter-individual variation in plasma apoE level, will yield new insights into the understanding of genetic interactions involved in the lipid metabolism, and a more precise understanding of the risk factors leading to CAD. ^
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Approximately one-third of US adults have metabolic syndrome, the clustering of cardiovascular risk factors that include hypertension, abdominal adiposity, elevated fasting glucose, low high-density lipoprotein (HDL)-cholesterol and elevated triglyceride levels. While the definition of metabolic syndrome continues to be much debated among leading health research organizations, the fact is that individuals with metabolic syndrome have an increased risk of developing cardiovascular disease and/or type 2 diabetes. A recent report by the Henry J. Kaiser Family Foundation found that the US spent $2.2 trillion (16.2% of the Gross Domestic Product) on healthcare in 2007 and cited that among other factors, chronic diseases, including type 2 diabetes and cardiovascular disease, are large contributors to this growing national expenditure. Bearing a substantial portion of this cost are employers, the leading providers of health insurance. In lieu of this, many employers have begun implementing health promotion efforts to counteract these rising costs. However, evidence-based practices, uniform guidelines and policy do not exist for this setting in regard to the prevention of metabolic syndrome risk factors as defined by the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III). Therefore, the aim of this review was to determine the effects of worksite-based behavior change programs on reducing the risk factors for metabolic syndrome in adults. Using relevant search terms, OVID MEDLINE was used to search the peer-reviewed literature published since 1998, resulting in 23 articles meeting the inclusion criteria for the review. The American Dietetic Association's Evidence Analysis Process was used to abstract data from selected articles, assess the quality of each study, compile the evidence, develop a summarized conclusion, and assign a grade based upon the strength of supporting evidence. The results revealed that participating in a worksite-based behavior change program may be associated in one or more improved metabolic syndrome risk factors. Programs that delivered a higher dose (>22 hours), in a shorter duration (<2 years) using two or more behavior-change strategies were associated with more metabolic risk factors being positively impacted. A Conclusion Grade of III was obtained for the evidence, indicating that studies were of weak design or results were inconclusive due to inadequate sample sizes, bias and lack of generalizability. These results provide some support for the continued use of worksite-based health promotion and further research is needed to determine if multi-strategy, intense behavior change programs targeting multiple risk factors are able to sustain health improvements in the long-term.^
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This paper presents a gravimetric study (based on 382 gravimetric stations in an area about 32 km2) of a nearly flat basin: the Low Andarax valley. This alluvial basin, close to its river mouth, is located in the extreme south of the province of Almería and coincides with one of the existing depressions in the Betic Cordillera. The paper presents new methodological work to adapt a published inversion approach (GROWTH method) to the case of an alluvial valley (sedimentary stratification, with density increase downward). The adjusted 3D density model reveals several features in the topography of the discontinuity layers between the calcareous basement (2,700 kg/m3) and two sedimentary layers (2,400 and 2,250 kg/m3). We interpret several low density alignments as corresponding to SE faults striking about N140?145°E. Some detected basement elevations (such as the one, previously known by boreholes, in Viator village) are apparently connected with the fault pattern. The outcomes of this work are: (1) new gravimetric data, (2) new methodological options, and (3) the resulting structural conclusions.