Oxidative Stress as an Underlying Contributor in the Development of Chronic Complications in Diabetes Mellitus

The high prevalence of diabetes mellitus and its increasing incidence worldwide, coupled with several complications observed in its carriers, have become a public health issue of great relevance. Chronic hyperglycemia is the main feature of such a disease, being considered the responsible for the establishment of micro and macrovascular complications observed in diabetes. Several efforts have been directed in order to better comprehend the pathophysiological mechanisms involved in the course of this endocrine disease. Recently, numerous authors have suggested that excess generation of highly reactive oxygen and nitrogen species is a key component in the development of complications invoked by hyperglycemia. Overproduction and/or insufficient removal of these reactive species result in vascular dysfunction, damage to cellular proteins, membrane lipids and nucleic acids, leading different research groups to search for biomarkers which would be capable of a proper and accurate measurement of the oxidative stress (OS) in diabetic patients, especially in the presence of chronic complications. In the face of this scenario, the present review briefly addresses the role of hyperglycemia in OS, considering basic mechanisms and their effects in diabetes mellitus, describes some of the more commonly used biomarkers of oxidative/nitrosative damage and includes selected examples of studies which evaluated OS biomarkers in patients with diabetes, pointing to the relevance of such biological components in general oxidative stress status of diabetes mellitus carriers.     

Docosahexaenoic Acid (DHA) and Docosapentaenoic Acid (DPAn-6) Algal Oils Reduce Inflammatory Mediators in Human Peripheral Mononuclear Cells In Vitro and Paw Edema In Vivo

The anti-inflammatory activity associated with fish oil has been ascribed to the long-chain polyunsaturated fatty acids (LC-PUFA), predominantly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Here we examined the anti-inflammatory effects of two DHA-rich algal oils, which contain little EPA, and determined the contribution of the constituent fatty acids, particularly DHA and docosapentaenoic acid (DPAn-6). In vitro, lipopolysaccharide (LPS)-stimulated Interleukin-1 beta (IL-1β) and Tumor Necrosis Factor-alpha (TNF-α) secretion in human peripheral blood mononuclear cells (PBMC) was inhibited with apparent relative potencies of DPAn-6 (most potent) > DHA > EPA. In addition, DPAn-6 decreased intracellular levels of cyclooxygenase-2 (COX-2) and was a potent inhibitor of pro-inflammatory prostaglandin E2 (PGE2) production. DHA/DPAn-6-rich DHA-S™ (DHA-S) algal oil was more effective at reducing edema in rats than DHA-rich DHA-T™ (DHA-T), suggesting that DPAn-6 has anti-inflammatory properties. Further in vivo analyses demonstrated that feeding DPAn-6 alone, provided as an ethyl ester, reduced paw edema to an extent approaching that of indomethacin and enhanced the anti-inflammatory activity of DHA when given in combination. Together, these results demonstrate that DPAn-6 has anti-inflammatory activity and enhances the effect of DHA in vitro and in vivo. Thus, DHA-S algal oil may have potential for use in anti-inflammatory applications.     

IDENTIFICATION OF THE C30H16 POLYCYCLIC AROMATIC HYDROCARBON BENZO[cd]NAPHTHO[1,2,3-lm]PERYLENE AS A PRODUCT OF THE SUPERCRITICAL PYROLYSIS OF A SYNTHETIC JET FUEL

Using high-pressure liquid chromatography (HPLC) with ultraviolet-visible (UV) diode-array and mass spectrometric detection, we have analyzed the products of a Fischer-Tropsch synthetic jet fuel pyrolyzed, under supercritical conditions, at 710°C and 42 atm. An eight-ring polycyclic aromatic hydrocarbon, benzo[cd]naphtho[1,2,3-lm]perylene, has been unequivocally identified among the product components by its characteristic ultraviolet-visible absorbance spectrum. First, the unknown product component's HPLC elution behavior and UV absorbance characteristics indicated that it was a planar benzologue of dibenzo[cd,lm]perylene, having a high length-to-breadth ratio. Next, the mass spectrum established the isomer family of the unknown compound as C₃₀H₁₆. The UV absorption spectrum was then progressively analyzed with different solvents to achieve the final identification of benzo[cd]naphtho[1,2,3-lm]perylene. Benzo[cd]naphtho[1,2,3-lm]perylene has never before been reported as a product in any combustion or pyrolysis study.     

Physically adjusted neutral detergent fiber system for lactating dairy cow rations. II: Development of feeding recommendations

The objective of this work was to leverage equations derived in a meta-analysis into an ensemble modeling system for estimating dietary physical and chemical characteristics required to maintain desired rumen conditions in lactating dairy cattle. Given the availability of data, responsiveness of ruminal pH to animal behaviors, and the chemical composition and physical form of the diet, mean ruminal pH was chosen as the primary rumen environment indicator. Physically effective fiber (peNDF) is defined as the fraction of neutral detergent fiber (NDF) that stimulates chewing activity and contributes to the floating mat of large particles in the rumen. The peNDF of feedstuffs is typically estimated by multiplying the NDF content by a particle size measure, resulting in an estimated index of effectiveness. We hypothesized that the utility of peNDF could be expanded and improved by dissociating NDF and particle size and considering other dietary factors, all integrated into a physically adjusted fiber system that can be used to estimate minimum particle sizes of TMR and diet compositions needed to maintain ruminal pH targets. Particle size measures of TMR were limited to those found with the Penn State particle separator (PSPS). Starting with specific diet characteristics, the system employed an ensemble of models that were integrated using a variable mixture of experts approach to generate more robust recommendations for the percentage of dietary DM material that should be retained on the 8-mm sieve of a PSPS. Additional continuous variables also integrated in the physically adjusted fiber system include the proportion of material (dry matter basis) retained on the 19- and 8-mm sieves of the PSPS, estimated mean particle size, the dietary concentrations of forage, forage NDF, starch, and NDF, and ruminally degraded starch and NDF. The system was able to predict that the minimum proportion of material (dry matter basis) retained on the 8-mm sieve should increase with decreasing forage NDF or dietary NDF. Additionally, the minimum proportion of dry matter material on the 8-mm sieve should increase with increasing dietary starch. Results of this study agreed with described interrelationships between the chemical and physical form of diets fed to dairy cows and quantified the links between NDF intake, diet particle size, and ruminal pH. Feeding recommendations can be interpolated from tables and figures included in this work.     

Study of the Fate of Lipophilic Wood Extractives During Acid Sulphite Pulping Process by Ultrasonic Solid-Liquid Extraction and Gas Chromatography Mass Spectrometry

Abstract

Lipophilic extractives in dissolving pulp are still a big concern for pulp industries due to their detrimental effect on the quality of pulp. Since lipophilic extractives remaining in pulp are trapped in low-accessible fiber structures, effective extraction methods need to be established for studying their fate in the process. A simple, ultrasonic, solid liquid extraction established in this study was found to be more effective in capturing extractive residues in all “elemental chlorine-free” bleaching stages. Its efficiency was dependent on the extraction temperature, time, and solvent composition. A linearly correlated removal pattern of sterols and unsaturated fatty acids by the bleaching sequence was observed. It was further found that the bleaching combination did not fully remove lipophilic extractives. This study suggests an opportunity to explore ultrasonication-based extraction as an effective extraction procedure prior to gas chromatography mass spectrometry analysis for monitoring extractives in pulp.     

The nature and outcomes of work: A replication and extension of interdisciplinary work-design research.

Research into the changing nature of work requires comprehensive models of work design. One such model is the interdisciplinary framework (M. A. Campion, 1988), which integrates 4 work-design approaches (motivational, mechanistic, biological, perceptual–motor) and links each approach to specific outcomes. Unfortunately, studies of this framework have used methods that disregard measurement error, overlook dimensions within each work-design approach, and treat each approach and outcome separately. This study reanalyzes data from M. A. Campion (1988), using structural equation models that incorporate measurement error, specify multiple dimensions for each work-design approach, and examine the work-design approaches and outcomes jointly. Results show that previous studies underestimate relationships between work-design approaches and outcomes and that dimensions within each approach exhibit relationships with outcomes that differ in magnitude and direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structured brief therapy with a focus on dreams or loss for clients with troubling dreams and recent loss.

The authors tested whether a focus on dreams added something specific to the therapy process beyond the structure of a 3-stage approach. Fourteen distressed clients with troubling dreams and recent loss of a loved one participated in brief structured therapy focused on dreams or loss. After therapy, clients in both conditions reported being satisfied with therapy, having lowered impact of the loss, gaining new insights about themselves, and having made changes. In addition, clients in the dream condition rated the process of therapy higher, became involved in the therapeutic process more quickly, gained more understanding of their dreams, liked the structure of therapy more, and kept fewer secrets from their therapists than clients in the loss condition. In contrast, clients in the loss condition gained more insight about the effects of the past and their loss and liked therapist guidance more than clients in the dream condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Brain activation while thinking about the self from another person’s perspective after traumatic brain injury in adolescents.

Deficits in self awareness and taking the perspective of others are often observed following traumatic brain injury (TBI). Nine adolescents (ages 12–19 years) who had sustained moderate to severe TBI after an average interval of 2.6 years and nine typically developing (TD) adolescents underwent functional MRI (fMRI) while performing a perspective taking task (D’Argembeau et al., 2007). Participants made trait attributions either from their own perspective or from that of the significant other. The groups did not differ in reaction time or on a consistency criterion. When thinking of the self from a third-person perspective, adolescents with TBI demonstrated greater activation in posterior brain regions implicated in social cognition, the left lingual gyrus (BA 18) and posterior cingulate (BA 31), extending into neighboring regions not generally associated with social cognition, that is, cuneus (BA 31) and parahippocampal gyrus, relative to TD adolescents. We postulate that adolescents with moderate to severe TBI recruited alternative neural pathways during perspective-taking because traumatic axonal injury disrupted their fronto-parietal networks mediating social cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)