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81.

Background

Diabetes mellitus is a risk factor for coronary artery disease and diabetic cardiomyopathy, and adversely impacts outcomes following coronary artery bypass grafting. Current treatments focus on macro-revascularization and neglect the microvascular disease typical of diabetes mellitus-induced cardiomyopathy (DMCM). We hypothesized that engineered smooth muscle cell (SMC)-endothelial progenitor cell (EPC) bi-level cell sheets could improve ventricular dysfunction in DMCM.

Methods

Primary mesenchymal stem cells (MSCs) and EPCs were isolated from the bone marrow of Wistar rats, and MSCs were differentiated into SMCs by culturing on a fibronectin-coated dish. SMCs topped with EPCs were detached from a temperature-responsive culture dish to create an SMC-EPC bi-level cell sheet. A DMCM model was induced by intraperitoneal streptozotocin injection. Four weeks after induction, rats were randomized into 3 groups: control (no DMCM induction), untreated DMCM, and treated DMCM (cell sheet transplant covering the anterior surface of the left ventricle).

Results

SMC-EPC cell sheet therapy preserved cardiac function and halted adverse ventricular remodeling, as demonstrated by echocardiography and cardiac magnetic resonance imaging at 8 weeks after DMCM induction. Myocardial contrast echocardiography demonstrated that myocardial perfusion and microvascular function were preserved in the treatment group compared with untreated animals. Histological analysis demonstrated decreased interstitial fibrosis and increased microvascular density in the SMC-EPC cell sheet-treated group.

Conclusions

Treatment of DMCM with tissue-engineered SMC-EPC bi-level cell sheets prevented cardiac dysfunction and microvascular disease associated with DMCM. This multi-lineage cellular therapy is a novel, translatable approach to improve microvascular disease and prevent heart failure in diabetic patients.
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82.
Biomechanics and Modeling in Mechanobiology - Targeted drug delivery (TDD) to abdominal aortic aneurysm (AAA) using a controlled and efficient approach has recently been a significant challenge. In...  相似文献   
83.
Novel thin film composite photocathodes based on device‐grade Cu(In,Ga)Se2 chalcopyrite thin film absorbers and transparent conductive oxide Pt‐implemented TiO2 layers on top are presented for an efficient and stable solar‐driven hydrogen evolution. Thin films of phase‐pure anatase TiO2 are implemented with varying Pt‐concentrations in order to optimize simultaneously i) conductivity of the films, ii) electrocatalytic activity, and iii) light‐guidance toward the chalcopyrite. Thereby, high incident‐photon‐to‐current‐efficiencies of more than 80% can be achieved over the full visible light range. In acidic electrolyte (pH 0.3), the most efficient Pt‐implemented TiO2–Cu(In,Ga)Se2 composite electrodes reveal i) photocurrent densities up to 38 mA cm?2 in the saturation region (?0.4 V RHE, reversible hydrogen electrode), ii) 15 mA cm?2 at the thermodynamic potential for H2‐evolution (0 V RHE), and iii) an anodic onset potential shift for the hydrogen evolution (+0.23 V RHE). It is shown that the gradual increase of the Pt‐concentration within the TiO2 layers passes through an efficiency‐ and stability‐maximum of the device (5 vol% of Pt precursor solution). At this maximum, optimized light‐incoupling into the device‐grade chalcopyrite light‐absorber as well as electron conductance properties within the surface layer are achieved while no degradation are observed over more than 24 h of operation.  相似文献   
84.
Physical and functional interactions define the molecular organization of the cell. Genetic interactions, or epistasis, tend to occur between gene products involved in parallel pathways or interlinked biological processes. High-throughput experimental systems to examine genetic interactions on a genome-wide scale have been devised for Saccharomyces cerevisiae, Schizosaccharomyces pombe, Caenorhabditis elegans and Drosophila melanogaster, but have not been reported previously for prokaryotes. Here we describe the development of a quantitative screening procedure for monitoring bacterial genetic interactions based on conjugation of Escherichia coli deletion or hypomorphic strains to create double mutants on a genome-wide scale. The patterns of synthetic sickness and synthetic lethality (aggravating genetic interactions) we observed for certain double mutant combinations provided information about functional relationships and redundancy between pathways and enabled us to group bacterial gene products into functional modules.  相似文献   
85.
The ability to recognize kin and thus behaviourally discriminate between conspecifics based on genetic relatedness is of importance both in acquiring inclusive fitness benefits and to enable optimal inbreeding. In primates, mechanisms allowing recognition of paternal relatives are of particular interest, given that in these mating systems patrilineal information is unlikely to be available via social familiarity. Humans use visual phenotype matching based on facial features to identify their own and other''s close relatives, and recent studies suggest similar abilities may be present in other species. However it is unclear to what extent familial resemblances remain detectable against the background levels of relatedness typically found within demes in the wild – a necessary condition if facial cues are to function in kin recognition under natural conditions. Here, we experimentally investigate whether parent-offspring relationships are discernible in rhesus macaque (Macaca mulatta) faces drawn from a large free-ranging population more representative of the latter scenario, and in which genetic relatedness has been well quantified from pedigrees determined via molecular markers. We used the human visual system as a means of integrating multiple types of facial cue simultaneously, and demonstrate that paternal, as well as maternal, resemblance to both sons and daughters can be detected even by human observers. Experts performed better than participants who lacked previous experience working with nonhuman primates. However the finding that even naïve individuals succeeded at the task underlines the strength of the phenotypic cues present in faces.  相似文献   
86.
To date, there has been little agreement on supporting the hypothesis that how some key vegetative traits of camelina (Camelina sativa (L.) Crantz var. ‘Soheil’) are dependent on plant biomass. Therefore, the main aim of this investigation was to quantify the relationship between the size of camelina plants and seed production across a broad-range of plant densities through modelling approaches. To make a wide range of plant densities, a fan design was used in eight replicates in an experimental field at Sari Agricultural Sciences and Natural Resources University, Iran. To quantify the relation between plant density and other plant traits, a regression analysis was carried out and the coefficient of determination (R2) was considered to evaluate the goodness of fit model. A power model (y = axb) could describe well the relationship between plant density (ranged 113–2905 plants m−2) and plant biomass, seed production, number of seeds per plant, stem diameter, and siliques number, with the coefficient of determination (R2) values of 0.85, 0.87, 0.65, 0.64, and 0.90, respectively. The harvest indexes were 13.8%–26.9%, depending on plant density. Seed production per plant was positively correlated to the siliques number (r = 0.85), the branch number (r = 0.80), and the seed number (r = 0.99) which could be key components of camelina seed production per plant. Furthermore, no significant correlation was found among plant height, thousand-seed weight, and harvest index with seed production per plant. In conclusion, plant biomass could be considered an important trait to predict plant growth models of camelina. Also, a lower plant density of camelina can be compensated by a greater number of siliques, branches and seeds per plant.  相似文献   
87.
The development of an effective vaccine against tuberculosis (Tb) represents one of the major medical challenges of this century. Mycobacterium bovis Bacille Calmette-Guerin (BCG), the only vaccine available at present, is mostly effective at preventing disseminated Tb in children, but shows variable protection against pulmonary Tb, the most common form in adults. The reasons for this poor efficacy are not completely understood, but there is evidence that T regulatory cells (Tregs) might be involved. Similarly, Tregs have been associated with the immunosuppression observed in patients infected with Tb and are therefore believed to play a role in pathogen persistence. Thus, Treg depletion has been postulated as a novel strategy to potentiate M. bovis BCG vaccination on one side, while on the other, employed as a therapeutic approach during chronic Tb infection. Yet since Tregs are critically involved in controlling autoimmune inflammation, elimination of Tregs may therefore also incur the danger of an excessive inflammatory immune response. Thus, understanding the dynamics and function of Tregs during mycobacterial infection is crucial to evaluate the potential of Treg depletion as a medical option. To address this, we depleted Tregs after infection with M. bovis BCG or Mycobacterium tuberculosis (Mtb) using DEREG mice, which express the diphtheria toxin (DT) receptor under the control of the FoxP3 locus, thereby allowing the selective depletion of FoxP3+ Tregs. Our results show that after depletion, the Treg niche is rapidly refilled by a population of DT-insensitive Tregs (diTregs) and bacterial load remains unchanged. On the contrary, impaired rebound of Tregs in DEREG × FoxP3GFP mice improves pathogen burden, but is accompanied by detrimental autoimmune inflammation. Therefore, our study provides the proof-of-principle that, although a high degree of Treg depletion may contribute to the control of mycobacterial infection, it carries the risk of autoimmunity.  相似文献   
88.
89.

Introduction

Cinnamon exerts insulin-enhancing activity in vitro and was demonstrated to improve blood glucose and lipid profiles in several human studies. Such effects may have an impact on metabolically stressed cows.

Objective

To study the effects of cinnamon supplementation during the transition from late pregnancy to early lactation on the metabolism in dairy cows.

Methods

Twenty-four Holstein cows (n?=?8/group) were assigned to either the control group (CTR; without supplementation) or the supplementation groups [supplemental cinnamon at 20 (LCIN) or 40 (HCIN) g/cow per day (d)] from 28 d before calving until 21 d thereafter. Blood samples were assayed for glucose, nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), and insulin; an index estimating insulin sensitivity (RQUICKI) was calculated. The serum metabolome was characterized in the samples collected from d 14 using a non-targeted approach.

Results

The serum concentrations of glucose and insulin did not differ among groups and followed a similar pattern over time. The serum NEFA concentrations were greater in LCIN (d 2, 7, and 14) and HCIN (d 14) than in CTR. On d 14 and 21, LCIN and HCIN had greater serum BHBA concentrations than CTR cows. The top 10 metabolites identified with significantly higher levels in the supplemented than the CTR cows were related to fatty acid metabolism.

Conclusion

The data suggest lipolytic and ketogenic effects of cinnamon supplementation in dairy cows during the transition from late gestation to early lactation. The fatty acid metabolites found elevated in the supplemented cows point towards impaired mitochondrial fatty acid β-oxidation.
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90.
This study evaluated several secondary metabolites, essential oils (EOs) compositions, and antioxidant activity in four medicinal plants that originated in Isfahan rangelands. The species were Astragalus verus, Astragalus adscendens, Daphne mucronata, and Phlomis olivieri. Thirty-two genotypes of these species were evaluated for different biochemical traits. Based on the evaluation of EOs compounds, GC/MS analysis revealed the total number of identified compounds. These compounds were 25, 22, 12, and 22 for A. adscendens, A. verus, D. mucronata, and P. olivieri, respectively. The dominant compounds were phthalate (59.88 %) in A. adscendens, phytol (38.02 %) in A. verus, hexanoic acid (32.05 %) in D. mucronata and β-cubebene (30.94 %) in P. olivieri. Phytochemical analysis showed that D. mucronata, A. adscendens, and P. olivieri had the highest total phenolics content (TPC) (18.24 mg gallic acid equivalent/g dry weight), total flavonoids content (5.57 mg QE/g DW), and total anthocyanins content (0.23 mg/g DW), respectively. The highest total chlorophyll (0.27 mg/g DW), total carotenoids (0.03 mg/g DW), and antioxidant activity (71.36 %) were observed in A. adscendens, A. adscendens and A. verus, respectively. Among all genotypes, the highest TPC (20.1 mg GAE/g DW) was observed in genotype 5 of D. mucronata. This study provided new information on the chemical compounds within the distribution range of these ecologically dominant rangeland species in Isfahan province, Iran. The data revealed that superior genotypes from these species are rich in natural antioxidants and bioactive compounds. Thus, they can be used in ethno pharmacological fields, food, and industrial applications.  相似文献   
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