109 research outputs found
Vascular endothelial growth factor B (VEGF-B) is up-regulated and exogenous VEGF-B is neuroprotective in a culture model of Parkinson's disease
Parkinson's disease (PD) results from the degeneration of dopaminergic neurons in the substantia nigra and the consequent deficit of dopamine released in the striatum. Current oral dopamine replacement or surgical therapies do not address the underlying issue of neurodegeneration, they neither slow nor halt disease. Neurotrophic factors have shown preclinical promise, but the choice of an appropriate growth factor as well as the delivery has proven difficult. In this study, we used a rotenone rat midbrain culture model to identify genes that are changed after addition of the neurotoxin. (1) We challenged rat midbrain cultures with rotenone (20 nM), a pesticide that has been shown to be toxic for dopaminergic neurons and that has been a well-characterized model of PD. A gene chip array analysis demonstrated that several genes were up-regulated after the rotenone treatment. Interestingly transcriptional activation of vascular endothelial growth factor B (VEGF-B) was evident, while vascular endothelial growth factor A (VEGF-A) levels remained unaltered. The results from the gene chip array experiment were verified with real time PCR and semi-quantitative western analysis using Ī²-actin as the internal standard. (2) We have also found evidence that exogenously applied VEGF-B performed as a neuroprotective agent facilitating neuron survival in an even more severe rotenone culture model of PD (40 nM rotenone). VEGF-B has very recently been added to the list of trophic factors that reduce effects of neurodegeneration, as was shown in an in vivo model of motor neuron degeneration, while lacking potential adverse angiogenic activity. The data of an in vivo protective effect on motor neurons taken together with the presented results demonstrate that VEGF-B is a new candidate trophic factor distinct from the GDNF family of trophic factors. VEGF-B is activated by neurodegenerative challenges to the midbrain, and exogenous application of VEGF-B has a neuroprotective effect in a culture model of PD. Strengthening this natural protective response by either adding exogenous VEGF-B or up-regulating the endogenous VEGF-B levels may have the potential to be a disease modifying therapy for PD. We conclude that the growth factor VEGF-B can improve neuronal survival in a culture model of PD
Statistical model for intergranular corrosion growth kinetics
A statistical model has been developed to predict the anisotropy of intergranular corrosion (IGC) kinetics and effect of microstructure on IGC kinetics in high strength AA2024-T3 alloys. The methodology is to estimate the statistical distribution of minimum IGC path length that will be found through the thickness of a given thickness ST sample using the principle of order statistics. A brick-wall model is adopted for wrought Al alloy microstructure and different distributions of grain dimension are assumed for the purpose of the estimation of total IGC path length. Numerical stimulation using a gamma distribution model stimulated the anisotropy of localized corrosion in AA2024-T3 alloys, which quite agrees with the growth rate anisotropy experimentally determined by the foil penetration technique. Some limitations regarding the statistical model are discussed. The statistical model provides a new approach to predicting and quantifying localized corrosion kinetics on basis of the alloy microstructure.This work was supported by the United States Air Force Office of Scientific Research through Grant no. F49620-99-1-0103
The Influence of Social Isolation and Medical Comorbidities on Geriatric Congestive Heart Failure Hospital Readmissions
CONTEXT Social isolation and comorbidities are likely to have a significant level of influence on the healthcare use patterns of geriatric patients with ongoing congestive heart failure (CHF)-related needs. METHODS A retrospective study was conducted in a specialized emergency department (ED) with a sample of 286 geriatric CHF patients who initially received CHF-related care over a six-month period. Social isolation levels were assessed using a pre-existing four-point screening tool used in the study setting and composite comorbidity was gauged using the Charlson Comorbidity Index method. Subjects were categorized into either āless than 30-day readmissionā or āgreater than 30-day readmission/non-readmittedā sample subgroups. The setting was a single 304-bed community hospital with approximately 45,000 annual ED visits. The analytic sample was comprised of geriatric patients 65+ years of age with an ICD-9 code corresponding to CHF. RESULTS There were no statistically significant differences between earlier hospital readmission versus later/non-readmitted sample patients when grouped by age, race, gender or level of measured social isolation. However, composite comorbidity scores were significantly lower for patients in the \u3e30-day/non-readmitted subgroup compared to earlier readmission patients. CONCLUSIONS These initial study results suggest that a larger proportion of CHF hospital readmissions may be more heavily influenced by clinical factors than social living arrangements. Future studies with larger samples and validated measures of social isolation are needed to inform the development and testing of programs for geriatric CHF patients striving to avoid unnecessary hospital readmissions and adverse health outcomes
PEDF and VEGF-A Output from Human Retinal Pigment Epithelial Cells Grown on Novel Microcarriers
Human retinal pigment epithelial (hRPE) cells have been tested as a cell-based therapy for Parkinson's disease but will require additional study before further clinical trials can be planned. We now show that the long-term survival and neurotrophic potential of hRPE cells can be enhanced by the use of FDA-approved plastic-based microcarriers compared to a gelatin-based microcarrier as used in failed clinical trials. The hRPE cells grown on these plastic-based microcarriers display several important characteristics of hRPE found in vivo: (1) characteristic morphological features, (2) accumulation of melanin pigment, and (3) high levels of production of the neurotrophic factors pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor-A (VEGF-A). Growth of hRPE cells on plastic-based microcarriers led to sustained levels (>1āng/ml) of PEDF and VEGF-A in conditioned media for two months. We also show that the expression of VEGF-A and PEDF is reciprocally regulated by activation of the GPR143 pathway. GPR143 is activated by L-DOPA (1āĪ¼M) which decreased VEGF-A secretion as opposed to the previously reported increase in PEDF secretion. The hRPE microcarriers are therefore novel candidate delivery systems for achieving long-term delivery of the neuroprotective factors PEDF and VEGF-A, which could have a value in neurodegenerative conditions such as Parkinson's disease
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An Innovative Take on Filtering Carbon Dioxide Through CryoCapture
Overview (Air Mover):
Carbon dioxide plays an important role in the earth's ecosystem; the lives of many organisms are based on the balancing of this gas. Plants and animals need it for survival however, an excess of carbon dioxide can also end the organismās life. The production of the gas mostly comes from the combustion of fossil fuel, power plants, big industries, vehicles, and processes involving natural gasses. One of the most known issues of carbon dioxide pollution is global warming. The greenhouse gas essentially traps heat in the atmosphere, increasing the global temperature.
The methodology provided is an innovative solution towards the creation of an environmentally friendly carbon dioxide filter. Current air filtration systems are restricted to industrial environments limiting the ability to filter the air. Due to the large noise and low range of operation of axial fans the filtration systems need controlled environments for longevity. The paper presents a versatile air mover that can be mounted onto multiple surfaces due to its low profile and bracket mounts. Furthermore, the usage of a diagonal fan inside of a PVC pipe allows for a durable system that can operate at high efficiency and low noise.
The main challenge in designing the air mover was figuring out how to quantify the scalability of the device and what parameters could be changed in order to make the device more viable. The designs most prominent feature are the inclusion of a modular enclosure that can be adapted to multiple areas and environments while withstanding harsh conditions due to the PVC piping that can be coated with a diagonal fan for high volumetric flow rates and pressure differential for versatility in environments the device is placed in as well as efficiency.
Overview (Carbon Storer):
The Civil and Environmental Engineering team is responsible for finding a cost effective and sustainable way to transport, store and recycle the carbon caught in the air from the Carbon Catcher designed by the other engineering teams. In the teamās design, the Carbon Catcher will reduce the harmful emissions in the air by capturing CO2, store it and then utilize it in another industry which will reduce the need to mine for more raw materials which would thus further reduce the pollution emitted into the environment.
Our plan is to recycle the carbon emitted from a factory and utilize it in CO2 dry ice. It's the Civil and Environmental Engineersā job to find a way to connect a sustainable solution with a solution that improves the publicās quality of life. There are many industries that pollute immense amounts from the mining of raw material or the emission of pollutants. The team wants to show industries that the economic solution can also be the sustainable solution.
Overview (Membrane)
The teamās solution focuses on the use of cryogenic carbon capture, a method in which the selective freezing points of the gaseous components of air are used to separate out carbon dioxide. For this process, the team will be utilizing a 4 step filtration process. First, the flue gas will be run through a particulate filter to catch all macroscopic particles that may be present within the air. Afterwards, the gas is then passed through a dehumidifier where a majority of water content will be extracted. Following this, The gas was then run through a long pipe and progressively cool it down to the freezing point of carbon dioxide. Finally, the filtered gas is extracted, and a bubbler is used to separate the solid carbon dioxide. The carbon dioxide is then compressed and recycled around the feed pipe to help in the cooling process.
Along the process of this design, the team encountered problems finding the optimum materials for temperatures this low. As well, coming up with a way to eliminate heat transfer from the outside posed a huge problem. Through the experience, the team was able to gain a greater view of what benefits and drawbacks must be balanced, along with the economic interest that comes with designing an efficient process.
Unlike how most designs are focused, It was understood that using a membrane only provided so much creativity when it came to filtration. As a result, the team researched other successful methods and arrived at utilizing cryogenics to filter.
Goal
Research to provide a single solution to remove levels of carbon dioxide in the immediate atmosphere, transport it to a storage mechanism, and find a way to recycle it. Powerful research is required to ensure effective methodologies, material usage, and flexible scalability of the overall device. This particular team seeks to find an alternative separation process to membrane filtration, the efficacy of which has not been demonstrated beyond the scale of a laboratory
3-Cinnamoyl-4-hydroxy-6-methyl-2H-pyran-2-one ameliorates diabetic peripheral neuropathy in type 2 diabetes mellitus rats via PI3K/Akt signaling pathway
Purpose: To investigate the curative effects of 3-cinnamoyl-4-hydroxy-6-methyl-2H-pyran-2-one (CHMP) on streptozotocin (STZ)-induced model of diabetic SD rats, and the underlying mechanism.
Method: Diabetes was induced in rats using single intraperitoneal injection of STZ. Subsequently, diabetic and non-diabetic rats were randomly grouped into five experimental groups. Six weeks after the STZ-injection, the diabetic animals were orally administered test compound (CHMP) at two doses of 10 and 20 mg/kg body weight for 6 weeks. Thereafter, the rats were anesthetised, and body weight, blood sugar, and motor nerve conduction velocity (MNCV) were determined. Moreover, real time-polymerase chain reaction (RT-PCR) and western blot analysis were used to assay the expression levels of genes in PIK3/Akt pathway and Glut4.
Results: Treatment of diabetic rats with CHMP significantly reduced levels of fasting blood glucose and enhanced average rat body weight, relative to diabetic control (p Ė 0.05). Motor nerve conduction velocity (MNCV) was remarkably increased in CHMP-treated rats (54.2 Ā± 2.2), when compared to the diabetic control rats (46 Ā± 4.1, p < 0.01). Results from RT-PCR and western blot indicated increased expressions of PI3K, Akt and IRS-1, and down regulation of GSK-3B expression in skeletal muscle. The CHMP treatment also upregulated the Glut4 expression in skeletal muscle.
Conclusion: These findings show that CHMP may be beneficial in the management of diabetic neuropath
Protective effect of the curcumin-baicalein combination against macrovascular changes in diabetic angiopathy
Endothelial dysfunction is an early pathological event in diabetic angiopathy which is the most common complication of diabetes. This study aims to investigate individual and combined actions of Curcumin (Cur) and Baicalein (Bai) in protecting vascular function. The cellular protective effects of Cur, Bai and Cur+Bai (1:1, w/w) were tested in H2O2 (2.5 mM) impaired EA. hy926 cells. Wistar rats were treated with vehicle control as the control group, Goto-Kakizaki rats (n=5 each group) were treated with vehicle control (model group), Cur (150 mg/kg), Bai (150 mg/kg), or Cur+Bai (75 mg/kg Cur + 75 mg/kg Bai, OG) for 4 weeks after a four-week high-fat diet to investigate the changes on blood vessel against diabetic angiopathy. Our results showed that Cur+Bai synergistically restored the endothelial cell survival and exhibited greater effects on lowering the fasting blood glucose and blood lipids in rats comparing to individual compounds. Cur+Bai repaired the blood vessel structure in the aortic arch and mid thoracic aorta. The network pharmacology analysis showed that Nrf2 and MAPK/JNK kinase were highly relevant to the multi-targeted action of Cur+Bai which has been confirmed in the in vitro and in vivo studies. In conclusion, Cur+Bai demonstrated an enhanced activity in attenuating endothelial dysfunction against oxidative damage and effectively protected vascular function in diabetic angiopathy rats
NTIRE 2023 Quality Assessment of Video Enhancement Challenge
This paper reports on the NTIRE 2023 Quality Assessment of Video Enhancement Challenge, which will be held in conjunction with the New Trends in Image Restoration and Enhancement Workshop (NTIRE) at CVPR 2023. This challenge is to address a major challenge in the field of video processing, namely, video quality assessment (VQA) for enhanced videos. The challenge uses the VQA Dataset for Perceptual Video Enhancement (VDPVE), which has a total of 1211 enhanced videos, including 600 videos with color, brightness, and contrast enhancements, 310 videos with deblurring, and 301 deshaked videos. The challenge has a total of 167 registered participants. 61 participating teams submitted their prediction results during the development phase, with a total of 3168 submissions. A total of 176 submissions were submitted by 37 participating teams during the final testing phase. Finally, 19 participating teams submitted their models and fact sheets, and detailed the methods they used. Some methods have achieved better results than baseline methods, and the winning methods have demonstrated superior prediction performance
Configuration and Stability of HF/SF6 and HF/N2 Standard Gases
In this paper, the analysis methods of HF components in two background series of nitrogen and sulfur hexafluoride were established and optimized. The uncertainty contribution in the weighing process was evaluated. The configuration of HF/SF6 and HF/N2 standard gases was established, that is, the packaging volume was 4L and 8L, and the content range of HF component was (50-100)Ć10-6 mol/mol. Then, the stability of the value of the standard gas is investigated, that is, the stability of the value with time and pressure, the fixed value and performance investigation. The relative expanded uncertainty of two series HF standard gas prediction is less than 6% (k=2)
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