37 resultados para Biological Markers -- blood


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The Mediterranean diet is associated with a lower incidence of atherosclerosis, cardiovascular disease, neurodegenerative diseases and certain types of cancer. The apparent health benefits have been partially ascribed to the dietary consumption of virgin olive oil by Mediterranean populations. Much research has focused on the biologically active phenolic compounds naturally present in virgin olive oils to aid in explaining reduced mortality and morbidity experienced by people consuming a traditional Mediterranean diet. Studies (human, animal, in vivo and in vitro) have demonstrated that olive oil phenolic compounds have positive effects on certain physiological parameters, such as plasma lipoproteins, oxidative damage, inflammatory markers, platelet and cellular function, antimicrobial activity and bone health. This paper summarizes current knowledge on the bioavailability and biological activities of olive oil phenolic compounds.

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The physiological adaptation to the erect posture involves integrated neural and cardiovascular responses that might be determined by genetic factors. We examined the familial- and individual-specific components of variance for postural changes in systolic and diastolic blood pressure in 767 volunteer nuclear adult families from the Victorian Family Heart Study. In 274 adult sibling pairs, we made a genome-wide scan using 400 markers for quantitative trait loci linked with the postural changes in systolic and diastolic pressures. Overall, systolic pressure did not change on standing, but there was considerable variation in this phenotype (SD=8.1 mm Hg). Familial analyses revealed that 25% of the variance of change in systolic pressure was attributable to genetic factors. In contrast, diastolic pressure increased by 6.3 mm Hg (SD=7.0 mm Hg) on standing and there was no evidence of contributory genetic factors. Multipoint quantitative genome linkage mapping suggested evidence (Z=3.2) of linkage of the postural change in systolic pressure to chromosome 12 but found no genome-wide evidence of linkage for the change in diastolic pressure. These findings suggest that genetic factors determine whether systolic pressure decreases or increases when one stands, possibly as the result of unidentified alleles on chromosome 12. The genetics of postural changes in systolic blood pressure might reflect the general buffering function of the baroreflex; thereby, the predisposition to sudden decreases or increases in systolic pressure might cause postural hypotension or vessel wall disruption, respectively.

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The gas, nitric oxide, plays a critical role in the control of the cardiovascular system of animals, and in particular blood pressure. This thesis demonstrated unique mechanisms by which nitric oxide regulates the blood vessels of various animals, which will alter our understanding of vascular regulation by peripheral nerves.

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This article summarizes the current knowledge available on metabolism and the biological effects of n-3 docosapentaenoic acid (DPA). n-3 DPA has not been extensively studied because of the limited availability of the pure compound. n-3 DPA is an elongated metabolite of EPA and is an intermediary product between EPA and DHA. The literature on n-3 DPA is limited, however the available data suggests it has beneficial health effects. In vitro n-3 DPA is retro-converted back to EPA, however it does not appear to be readily metabolised to DHA. In vivo studies have shown limited conversion of n-3 DPA to DHA, mainly in liver, but in addition retro-conversion to EPA is evident in a number of tissues. n-3 DPA can be metabolised by lipoxygenase, in platelets, to form ll-hydroxy-7,9,13,16,19- and 14-hydroxy-7,10,12,16,19-DPA. It has also been reported that n-3 DPA is effective (more so than EPA and DHA) in inhibition of aggregation in platelets obtained from rabbit blood. In addition, there is evidence that n-3 DPA possesses 10-fold greater endothelial cell migration ability than EPA, which is important in wound-healing processes. An in vivo study has reported that n-3 DPA reduces the fatty acid synthase and malic enzyme activity levels in n-3 DPA-supplemented mice and these effects were stronger than the EPA-supplemented mice. Another recent in vivo study has reported that n-3 DPA may have a role in attenuating age-related decrease in spatial learning and long-term potentiation. However, more research remains to be done to further investigate the biological effects of this n-3 VLCPUFA.

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This paper introduces a method of modeling noninvasive glucose sensing for patients who suffer from diabetes mellitus. The proposed technique involves simulation of light propagation through biological tissue with an embedded photonic crystal. The proposed detection technique is Raman spectroscopy and the use of the photonic crystal enables the enhancement of Raman scattering by engineering the photon density of states. Further enhancement can be achieved using noble metal clusters which result in surface enhanced Raman scattering and has the ability to provide enhancements of up to a million times.

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Lineage-specific expansion of haematopoietic stem/progenitor cells (HSPCs) from human umbilical cord blood (UCB) is desirable because of their several applications in translational medicine, e.g. treatment of cancer, bonemarrowfailure and immunodeficiencies. The currentmethods forHSPC expansion use either cellular feeder layers and/or soluble growth factors and selected matrix components coated on different surfaces. The use of cell-free extracellular matrices from bone marrow cells for this purpose has not previously been reported. We have prepared insoluble, cell- free matrices from a murine bone marrow stromal cell line (MS-5) grown under four different conditions, i.e. in presence or absence of osteogenic medium, each incubated under 5% and 20% O2 tensions. These acellularmatrices were used as biological scaffolds for the lineage-specific expansion of magnetically sorted CD34+ cells and the results were evaluated by flow cytometry and colony-forming assays. We could get up to 80-fold expansion of some HSPCs on one of the matrices and our results indicated that oxygen tension played a significant role in determining the expansion capacity of the matrices. A comparative proteomic analysis of the matrices indicated differential expression of proteins, such as aldehyde dehydrogenase and gelsolin, which have previously been identified as playing a role in HSPC maintenance and expansion. Our approach may be of value in identifying factors relevant to tissue engineering-based ex vivo HSPC expansion, and itmay also provide insights into the constitution of the niche in which these cells reside in the bone marrow.

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Multiple studies have demonstrated an association between cigarette smoking and increased anxiety symptoms or disorders, with early life exposures potentially predisposing to enhanced anxiety responses in later life. Explanatory models support a potential role for neurotransmitter systems, inflammation, oxidative and nitrosative stress, mitochondrial dysfunction, neurotrophins and neurogenesis, and epigenetic effects, in anxiety pathogenesis. All of these pathways are affected by exposure to cigarette smoke components, including nicotine and free radicals. This review critically examines and summarizes the literature exploring the role of these systems in increased anxiety and how exposure to cigarette smoke may contribute to this pathology at a biological level. Further, this review explores the effects of cigarette smoke on normal neurodevelopment and anxiety control, suggesting how exposure in early life (prenatal, infancy, and adolescence) may predispose to higher anxiety in later life. A large heterogenous literature was reviewed that detailed the association between cigarette smoking and anxiety symptoms and disorders with structural brain changes, inflammation, and cell-mediated immune markers, markers of oxidative and nitrosative stress, mitochondrial function, neurotransmitter systems, neurotrophins and neurogenesis. Some preliminary data were found for potential epigenetic effects. The literature provides some support for a potential interaction between cigarette smoking, anxiety symptoms and disorders, and the above pathways; however, limitations exist particularly in delineating causative effects. The literature also provides insight into potential effects of cigarette smoke, in particular nicotine, on neurodevelopment. The potential treatment implications of these findings are discussed in regards to future therapeutic targets for anxiety. The aforementioned pathways may help mediate increased anxiety seen in people who smoke. Further research into the specific actions of nicotine and other cigarette components on these pathways, and how these pathways interact, may provide insights that lead to new treatment for anxiety and a greater understanding of anxiety pathogenesis.

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The fluid component of blood is widely used in ecophysiological investigations, including measures of immune function and stable isotope ecology. After blood collection, delayed separation of blood extracellular fluids from red blood cells is known to affect the concentration of a wide range of biochemical compounds in the resulting fluid, as does prevention of clotting (producing plasma) when compared with blood allowed to clot (producing serum). One challenge when investigating immune function and stable isotope ecology, therefore, is discriminating variation because of the effect of the biological factors of interest from potential methodological artefacts. This study assesses how seven widely used measures of immune function and stable isotope composition respond both to delayed separation of the cellular and fluid components and to the clotting of blood samples from two species of waterfowl. Samples that remained uncentrifuged for up to 12 h did not differ from those centrifuged within 15 min of sampling from the same individuals, indicating that samples from a wide range of field conditions may remain highly comparable. However, the outcome of three of the four immunological assays and two of the three isotopic analyses was highly dependent on the type of fluid, with higher immunological activity and higher relative concentrations of heavy carbon and total nitrogen in plasma compared to serum. Researchers interested in immune function and stable isotope ecology may obtain the most useful results by ensuring that they use a single fluid type in their investigations.

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SUMMARY
Background & aims
It has been previously reported that pasta containing wholegrain sorghum flour exhibits high content of polyphenols and antioxidant capacity and hence might enhance antioxidant status and reduce markers of oxidative stress in vivo; however no clinical studies have yet been reported. Therefore, the present study assessed the effect of pasta containing red or white wholegrain sorghum flour on plasma total polyphenols, antioxidant capacity and oxidative stress markers in humans. The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN: 12612000324819).

Methods
In a randomised crossover design, healthy subjects (n = 20) consumed three test meals of control pasta (CP), 30% red sorghum pasta (RSP) or 30% white sorghum pasta (WSP), 1–2 wk apart. The test meals were consumed as breakfast after an overnight fast. Blood samples were obtained at fasting and 2 h after consumption and analysed for total polyphenols, antioxidant capacity, superoxide dismutase (SOD) activity, protein carbonyl and 8-isoprostanes.

Results
Compared to baseline, the 2 h post-prandial levels following the RSP meal of plasma polyphenols, antioxidant capacity and SOD activity were significantly (P < 0.001) higher while the protein carbonyl level was significantly lower (P = 0.035). Furthermore, net changes in polyphenols, antioxidant capacity and SOD activity were significantly (P < 0.001) higher while protein carbonyl were significantly (P = 0.035) lower following consumption of the RSP meal than the CP meal.

Conclusion
The results demonstrated that pasta containing red wholegrain sorghum flour enhanced antioxidant status and diminished marker of oxidative stress in healthy subjects.

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A socioeconomic gradient exists in Australia for type 2 diabetes mellitus (T2DM). It remains unclear whether economic hardship is associated with T2DM self-management behaviours.

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A century after its discovery, Chagas disease still represents a major neglected tropical threat. Accurate diagnostics tools as well as surrogate markers of parasitological response to treatment are research priorities in the field. The purpose of this study was to evaluate the performance of PCR methods in detection of Trypanosoma cruzi DNA by an external quality evaluation.

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Lubricin is a glycoprotein found in articular joints which has been recognized as being an important biological boundary lubricant molecule. Besides providing lubrication, we demonstrate, using a quartz crystal microbalance, that lubricin also exhibits anti-adhesive properties and is highly effective at preventing the non-specific adsorption of representative globular proteins and constituents of blood plasma. This impressive anti-adhesive property, combined with lubricin's ability to readily self-assemble to form dense, highly stable telechelic polymer brush layers on virtually any substrates, and its innate biocompatibility, makes it an attractive candidate for anti-adhesive and anti-fouling coatings. We show that coatings of lubricin protein are as effective as, or better than, self-assembled monolayers of polyethylene glycol over a wide range of pH and that this provides a simple, versatile, highly stable, and highly effective method of controlling unwanted adhesion to surfaces.

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UNLABELLED: During and after prolonged bed rest, changes in bone metabolic markers occur within 3 days. Resistive vibration exercise during bed rest impedes bone loss and restricts increases in bone resorption markers whilst increasing bone formation. INTRODUCTION: To investigate the effectiveness of a resistive vibration exercise (RVE) countermeasure during prolonged bed rest using serum markers of bone metabolism and whole-body dual X-ray absorptiometry (DXA) as endpoints. METHODS: Twenty healthy male subjects underwent 8 weeks of bed rest with 12 months follow-up. Ten subjects performed RVE. Blood drawings and DXA measures were conducted regularly during and after bed rest. RESULTS: Bone resorption increased in the CTRL group with a less severe increase in the RVE group (p = 0.0004). Bone formation markers increased in the RVE group but decreased marginally in the CTRL group (p < 0.0001). At the end of bed rest, the CTRL group showed significant loss in leg bone mass (-1.8(0.9)%, p = 0.042) whereas the RVE group did not (-0.7(0.8)%, p = 0.405) although the difference between the groups was not significant (p = 0.12). CONCLUSIONS: The results suggest the countermeasure restricts increases in bone resorption, increased bone formation, and reduced bone loss during bed rest.

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Blood samples collected from members of indigenous communities in the mid-20th century by scientists interested in human variation remain frozen today in institutional repositories around the world. This article focuses on two such collections-one established and maintained in the United States and the other in Australia. Through historical and ethnographic analysis, we show how scientific knowledge about the human species and ethical knowledge about human experimentation are coproduced differently in each national context over time. Through a series of vignettes, we trace the attempts of scientists and indigenous people to assemble and reassemble blood samples, ethical regimes, human biological knowledge, and personhood. In including ourselves-a U.S. historian of science and an Australian anthropologist-in the narrative, we show how humanistic and social scientific analysis contributes to ongoing efforts to maintain indigenous samples. [indigenous, biospecimens, science, genomics, postcolonial, ethics, cryopreservation].