Accumulation rates of sediments and main sedimentary components in ODP Leg 121 holes on Broken Ridge

Broken Ridge, in the eastern Indian Ocean,is overlain by about 1600 m of middle Cretaceous to Pleistocene tuffaceous and carbonate sediments that record the oceanographic history of southern hemisphere mid-to high-latitude regions. Prior to about 42 Ma, Broken Ridge formed the northern part of the broad Kerguelen-Broken Ridge Plateau. During the middle Eocene, this feature was split by the newly forming Southeast Indian Ocean Ridge; since then, Broken Ridge has drifted north from about 55° to 31°S. The lower part of the sedimentary section is characterized by Turonian to Santonian tuffs that contain abundant glauconite and some carbonate. The tuffs record a large but apparently local volcanic input that characterized the central part of Broken Ridge into the early Tertiary. Maestrichtian shallow-water(several hundred to 1000 m depth) limestones and cherts accumulated at some of the highest rates ever documented from the open ocean, 4 to 5 g/cm**2/kyr. A complete (with all biostratigraphic zones) Cretaceous-Tertiary boundary section was recovered from site 752. The first 1.5 m.y. of the Tertiary is characterized by an order-of-magnitude reduction in the flux of biogenic sediments, indicating a period of sharply reduced biological productivity at 55°S, following which the carbonate and silica sedimentation rates almost reach the previous high values of the latest Cretaceous. We recovered a complete section through the Paleocene that contains all major fossil groups and is more than 300 m thick, perhaps the best pelagic Paleocene section encountered in ocean drilling. About 42 Ma, Broken Ridge was uplifted 2500 m in response to the intra-plateau rifting event; subsequent erosion and deposition has resulted in a prominent Eocene angular unconformity atop the ridge. An Oligocene disconformity characterized by a widespread pebble layer probably represents the 30 Ma sea-level fall. The Neogene pelagic ooze on Broken Ridge has been winnowed, and thus its grain size provides a direct physical record of the energy of the southern hemisphere drift current in the Indian Ocean for the past 30 m.y.

Influence of food components on lipid metabolism: scenarios and perspective on the control and prevention of dyslipidemias

Cardiovascular diseases (CVD) are the main causes of death in the Western world. Among the risk factors that are modifiable by diet, for reducing cardiovascular disease risks, the total plasma concentrations of cholesterol, triglycerides, LDL-C, and HDL-C are the most important. Dietary measures can balance these components of the lipid profile thus reducing the risk of cardiovascular diseases. The main food components that affect the lipid profile and can be modified by diet are the saturated and trans fats, unsaturated fats, cholesterol, phytosterols, plant protein, and soluble fiber. A wealth of evidence suggests that saturated and trans fats and cholesterol in the diet raise the total plasma cholesterol and LDL-C. Trans fats also reduce HDL-C, an important lipoprotein for mediating the reverse cholesterol transport. On the other hand, phytosterols, plant proteins, isoflavones, and soluble fiber are protective diet factors against cardiovascular diseases by modulating plasma lipoprotein levels. These food components at certain concentrations are able to reduce the total cholesterol, TG, and LDL-C and raise the plasma levels of HDL-C. Therefore, diet is an important tool for the prevention and control of cardiovascular diseases, and should be taken into account as a whole, i.e., not only the food components that modulate plasma concentrations of lipoproteins, but also the diet content of macro nutrients and micronutrients should be considered.

Metabolic syndrome and dietary components are associated with coronary artery disease risk score in free-living adults: a cross-sectional study

Background: Coronary artery disease (CAD) is among the main causes of death in developed countries, and diet and lifestyle can influence CAD incidence. Objective: To evaluate the association of coronary artery disease risk score with dietary, anthropometric and biochemical components in adults clinically selected for a lifestyle modification program. Methods: 362 adults (96 men, 266 women, 53.9 +/- 9.4 years) fulfilled the inclusion criteria by presenting all the required data. The Framingham score was calculated and the IV Brazilian Guideline on Dyslipidemia and Prevention of Atherosclerosis was adopted for classification of the CAD risks. Anthropometric assessments included waist circumference (WC), body fat and calculated BMI (kg/m(2)) and muscle-mass index (MMI kg/m(2)). Dietary intake was estimated through 24 h dietary recall. Fasting blood was used for biochemical analysis. Metabolic Syndrome (MS) was diagnosed using NCEP-ATPIII (2001) criteria. Logistic regression was used to determine the odds of CAD risks according to the altered components of MS, dietary, anthropometric, and biochemical components. Results: For a sample with a BMI 28.5 +/- 5.0 kg/m(2) the association with lower risk (<10% CAD) were lower age (<60 years old), and plasma values of uric acid. The presence of MS within low, intermediary, and high CAD risk categories was 30.8%, 55.5%, and 69.8%, respectively. The independent risk factors associated with CAD risk score was MS and uric acid, and the protective factors were recommended intake of saturated fat and fiber and muscle mass index. Conclusion: Recommended intake of saturated fat and dietary fiber, together with proper muscle mass, are inversely associated with CAD risk score. On the other hand, the presence of MS and high plasma uric acid are associated with CAD risk score.

Fluorescence and reflectance spectroscopy for identification of atherosclerosis in human carotid arteries using principal components analysis

Objectives: The aim of this work was to verify the differentiation between normal and pathological human carotid artery tissues by using fluorescence and reflectance spectroscopy in the 400- to 700-nm range and the spectral characterization by means of principal components analysis. Background Data: Atherosclerosis is the most common and serious pathology of the cardiovascular system. Principal components represent the main spectral characteristics that occur within the spectral data and could be used for tissue classification. Materials and Methods: Sixty postmortem carotid artery fragments (26 non-atherosclerotic and 34 atherosclerotic with non-calcified plaques) were studied. The excitation radiation consisted of a 488-nm argon laser. Two 600-mu m core optical fibers were used, one for excitation and one to collect the fluorescence radiation from the samples. The reflectance system was composed of a halogen lamp coupled to an excitation fiber positioned in one of the ports of an integrating sphere that delivered 5 mW to the sample. The photo-reflectance signal was coupled to a 1/4-m spectrograph via an optical fiber. Euclidean distance was then used to classify each principal component score into one of two classes, normal and atherosclerotic tissue, for both fluorescence and reflectance. Results: The principal components analysis allowed classification of the samples with 81% sensitivity and 88% specificity for fluorescence, and 81% sensitivity and 91% specificity for reflectance. Conclusions: Our results showed that principal components analysis could be applied to differentiate between normal and atherosclerotic tissue with high sensitivity and specificity.