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21.

Background

Experimental autoimmune encephalomyelitis (EAE) is the most commonly studied animal model of multiple sclerosis (MS), a chronic autoimmune demyelinating disorder of the central nervous system. Immunomodulatory and immunosuppressive therapies currently approved for the treatment of MS slow disease progression, but do not prevent it. A growing body of evidence suggests additional mechanisms contribute to disease progression. We previously demonstrated the amelioration of myelin oligodendrocyte glycoprotein (MOG)-induced EAE in C57BL/6 mice by 670 nm light-induced photobiomodulation, mediated in part by immune modulation. Numerous other studies demonstrate that near-infrared/far red light is therapeutically active through modulation of nitrosoxidative stress. As nitric oxide has been reported to play diverse roles in EAE/MS, and recent studies suggest that axonal loss and progression of disability in MS is mediated by nitrosoxidative stress, we investigated the effect of 670 nm light treatment on nitrosative stress in MOG-induced EAE.

Methodology

Cell culture experiments demonstrated that 670 nm light-mediated photobiomodulation attenuated antigen-specific nitric oxide production by heterogenous lymphocyte populations isolated from MOG immunized mice. Experiments in the EAE model demonstrated down-regulation of inducible nitric oxide synthase (iNOS) gene expression in the spinal cords of mice with EAE over the course of disease, compared to sham treated animals. Animals receiving 670 nm light treatment also exhibited up-regulation of the Bcl-2 anti-apoptosis gene, an increased Bcl-2:Bax ratio, and reduced apoptosis within the spinal cord of animals over the course of disease. 670 nm light therapy failed to ameliorate MOG-induced EAE in mice deficient in iNOS, confirming a role for remediation of nitrosative stress in the amelioration of MOG-induced EAE by 670 nm mediated photobiomodulation.

Conclusions

These data indicate that 670 nm light therapy protects against nitrosative stress and apoptosis within the central nervous system, contributing to the clinical effect of 670 nm light therapy previously noted in the EAE model.  相似文献   
22.
Mycopathologia - Talaromycosis is a disseminated disease caused by Talaromyces (Penicillium) marneffei, mainly seen in acquired immunodeficiency syndrome (AIDS) patients. Its distribution is...  相似文献   
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On a microgrooved substrate, cells migrate along the pattern, and at random positions, reverse their directions. Here, we demonstrate that these reversals can be controlled by introducing discontinuities to the pattern. On “V-shaped grating patterns”, mouse osteogenic progenitor MC3T3-E1 cells reversed predominately at the bends and the ends. The patterns were engineered in a way that the combined effects of angle- and length-dependence could be examined in addition to their individual effects. Results show that when the bend was placed closer to one end, migration behaviour of cells depends on their direction of approach. At an obtuse bend (135°), more cells reversed when approaching from the long segment than from the short segment. But at an acute bend (45°), this relationship was reversed. Based on this anisotropic behaviour, the designed patterns effectively allowed cells to move in one direction but blocked migrations in the opposing direction. This study demonstrates that by the strategic placement of bends and ends on grating patterns, we can engineer effective unidirectional switching gates that can control the movement of adherent cells. The knowledge developed in this study could be utilised in future cell sorting or filtering platforms without the need for chemotaxis or microfluidic control.  相似文献   
25.
The application of high‐throughput sequencing‐based approaches to DNA extracted from environmental samples such as gut contents and faeces has become a popular tool for studying dietary habits of animals. Due to the high resolution and prey detection capacity they provide, both metabarcoding and shotgun sequencing are increasingly used to address ecological questions grounded in dietary relationships. Despite their great promise in this context, recent research has unveiled how a wealth of biological (related to the study system) and technical (related to the methodology) factors can distort the signal of taxonomic composition and diversity. Here, we review these studies in the light of high‐throughput sequencing‐based assessment of trophic interactions. We address how the study design can account for distortion factors, and how acknowledging limitations and biases inherent to sequencing‐based diet analyses are essential for obtaining reliable results, thus drawing appropriate conclusions. Furthermore, we suggest strategies to minimize the effect of distortion factors, measures to increase reproducibility, replicability and comparability of studies, and options to scale up DNA sequencing‐based diet analyses. In doing so, we aim to aid end‐users in designing reliable diet studies by informing them about the complexity and limitations of DNA sequencing‐based diet analyses, and encourage researchers to create and improve tools that will eventually drive this field to its maturity.  相似文献   
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The prenatal nutritional environment influences the subsequent risk of hypertension in adulthood. Animal studies have used, generally, the rat as a model species to illustrate the association between maternal nutrient intake and blood pressure in the resulting adult offspring. No study to date has shown programming of adult cardiovascular function in the sheep through maternal dietary intervention. We therefore fed pregnant sheep to either 100% recommended intake from day 0 of gestation to term [ approximately 147 days gestational age (dGA); controls n = 8] or to 50% recommended intake from day 0 to 95 dGA and thereafter to 100% intake (NR; n = 9). Sheep lambed naturally, offspring were weaned at 16 wk, and the male offspring were reared on pasture until 3 yr of age. At this time, cardiovascular catheters were inserted under halothane anesthesia and sheep were allowed 2-4 days recovery. Basal cardiovascular status and pressor responses to infusion of norepinephrine, angiotensin II, and captopril were then assessed alongside basal plasma concentrations of glucose, cortisol, and leptin. NR sheep were of similar birth weight to controls but at 3 yr of age had higher blood pressure before, but not after, feeding. Peripheral sensitivity to vasoconstrictor infusion was similar between dietary groups, although a reflex bradycardia was not apparent in NR sheep during norepinephrine infusion. Circulating leptin correlated well with fat mass and increased more after vasoconstrictor infusion in NR sheep. In conclusion, early NR has been shown to program aspects of cardiovascular control and adipocyte function in adult sheep.  相似文献   
28.

Background  

Conserved protein sequence motifs are short stretches of amino acid sequence patterns that potentially encode the function of proteins. Several sequence pattern searching algorithms and programs exist foridentifying candidate protein motifs at the whole genome level. However, amuch needed and importanttask is to determine the functions of the newly identified protein motifs. The Gene Ontology (GO) project is an endeavor to annotate the function of genes or protein sequences with terms from a dynamic, controlled vocabulary and these annotations serve well as a knowledge base.  相似文献   
29.
Mustard sawfly, A. lugens proxima, was found to be highly susceptible to entomopathogenic nematode, S. feltiae under laboratory condition. Application of three different doses of S. feltiae, viz. 1.1 x 10(3), 1.1 x 10(4) and 1.1 x 10(5) infective juveniles/ml, at weekly intervals, significantly reduced the field population of mustard sawfly on radish. The mean larval population of A. lugens proxima in all doses of nematode treated plots ranged from 0.42 to 0.48 larvae per plant as against 2.95 larvae / plant in untreated control plots. Similarly, the yield of radish in all the nematode treated plots was significantly higher by way of recording 2.80 to 2.87 tons/ha as compared to 1.63 tons/ha in the case of control.  相似文献   
30.
Cadherin adhesion molecules function in numerous cell biological processes that influence embryo development, normal cell physiology, and pathophysiology of many disease processes. Cadherins nucleate the assembly of the adherens junction, a cell-to-cell adhesion plaque that is prominent in simple epithelial cells and found in many cell types. Numerous cell biological approaches have been used to study this interesting class of molecules. Here, we outline methodology used in our studies of junctional complexes to examine effects of signaling molecules on assembly mechanisms. This is a quantitative method that allows the investigator to test the combined effect of two different signaling processes to determine whether these two signals act in concert within the same pathway. We discuss how this method could be generalized to other studies to examine consequences of various experimental manipulations on the assembly of cellular structures.  相似文献   
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