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141.

Background

Chronic hepatitis C virus infection is a major cause of liver disease in Switzerland and carries a significant cost burden. Currently, only conservative strategies are in place to mitigate the burden of hepatitis C in Switzerland. This study expands on previously described modeling efforts to explore the impact of: no treatment, and treatment to reduce HCC and mortality. Furthermore, the costs associated with untreated HCV were modeled.

Methods

Hepatitis C disease progression and mortality were modeled. Baseline historical assumptions were collected from the literature and expert interviews and strategies were developed to show the impact of different levels of intervention (improved drug cure rates, treatment and diagnosis) until 2030.

Results

Under the historical standard of care, the number of advanced stage cases was projected to increase until 2030, at which point the annual economic burden of untreated viremic infections was projected to reach €96.8 (95% Uncertainty Interval: €36 – €232) million. Scenarios to reduce HCV liver-related mortality by 90% by 2030 required treatment of 4,190 ≥F2 or 3,200 ≥F3 patients annually by 2018 using antivirals with a 95% efficacy rate. Delaying the implementation of these scenarios by 2 or 5 years reduced the impact on mortality to 75% and 57%, respectively.

Conclusions

With today’s treatment efficacy and uptake rates, hepatitis C disease burden is expected to increase through 2030. A substantial reduction in disease burden can be achieved by means of both higher efficacy drugs and increased treatment uptake. However, these efforts cannot be undertaken without a simultaneous effort to diagnose more infections.  相似文献   
142.
The synthesis of exopolysaccharides as biofilm matrix components by pathogens is a crucial factor for chronic infections and antibiotic resistance. Many periplasmic proteins involved in polymer processing and secretion in Gram-negative synthase dependent exopolysaccharide biosynthetic systems have been individually characterized. The operons responsible for the production of PNAG, alginate, cellulose and the Pel polysaccharide each contain a gene that encodes an outer membrane associated tetratricopeptide repeat (TPR) domain containing protein. While the TPR domain has been shown to bind other periplasmic proteins, the functional consequences of these interactions for the polymer remain poorly understood. Herein, we show that the C-terminal TPR region of PgaA interacts with the de-N-acetylase domain of PgaB, and increases its deacetylase activity. Additionally, we found that when the two proteins form a complex, the glycoside hydrolase activity of PgaB is also increased. To better understand structure-function relationships we determined the crystal structure of a stable TPR module, which has a conserved groove formed by three repeat motifs. Tryptophan quenching, mass spectrometry analysis and molecular dynamics simulation studies suggest that the crystallized TPR module can bind PNAG/dPNAG via its electronegative groove on the concave surface, and potentially guide the polymer through the periplasm towards the porin for export. Our results suggest a scaffolding role for the TPR domain that combines PNAG/dPNAG translocation with the modulation of its chemical structure by PgaB.  相似文献   
143.
Medicare conducted a payment demonstration to evaluate the effectiveness of two intensive lifestyle modification programs in patients with symptomatic coronary artery disease: the Dr. Dean Ornish Program for Reversing Heart Disease (Ornish) and Cardiac Wellness Program of the Benson-Henry Mind Body Institute. This report describes the changes in cardiac risk factors achieved by each program during the active intervention year and subsequent year of follow-up. The demonstration enrolled 580 participants who had had an acute myocardial infarction, had undergone coronary artery bypass graft surgery or percutaneous coronary intervention within 12 months, or had documented stable angina pectoris. Of these, 98% completed the intense 3-month intervention, 71% the 12-month intervention, and 56% an additional follow-up year. Most cardiac risk factors improved significantly during the intense intervention period in both programs. Favorable changes in cardiac risk factors and functional cardiac capacity were maintained or improved further at 12 and 24 months in participants with active follow-up. Multivariable regressions found that risk-factor improvements were positively associated with abnormal baseline values, Ornish program participation for body mass index and systolic blood pressure, and with coronary artery bypass graft surgery. Expressed levels of motivation to lose weight and maintain weight loss were significant independent predictors of sustained weight loss (p = 0.006). Both lifestyle modification programs achieved well-sustained reductions in cardiac risk factors.  相似文献   
144.
Among different tissues, endothelial/cardiac types require specific factors to promote myocardial regeneration after occurred injuries. Herein, cardiac stem cells (CSCs) as the major cell population that involved in cardiovascular repair were selected to study the role of polyethyleneimine (PEI) agent on endothelial differentiation. After preparation of electrospun network of PEI with polyacrylonitrile, the related characterizations were carried out including scanning electron microscope (SEM), field-emission SEM, water contact angle, Fourier transform infrared spectroscopy and mechanical properties. Also, the release kinetic of the corresponding agent was studied up to 7 days. The cell differentiation studies were done in the following with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, Real-time polymerase chain reaction and immunostaining method. The whole obtained results approved the higher differentiation of CSCs into endothelial/cardiac cells. Finally, it is recommended that the PEI delivering increases the healing potency of CSCs and accordingly the regeneration speed of damaged cardiovascular tissue would be improved.  相似文献   
145.
Tissue engineering is an interdisciplinary expertise that involves the use of nanoscaffolds for repairing, modifying, and removing tissue defects and formation of new tissues. Mesenchymal stem cells (MSCs) can differentiate into a variety of cell types, and they are attractive candidates for tissue engineering. In the current study, the electrospinning process was used for nanofiber preparation, based on a poly-l -lactic-acid (PLLA) polymer. The surface was treated with O 2 plasma to enhance hydrophilicity, cell attachment, growth, and differentiation potential. The nanoscaffolds were preconditioned with lipopolysaccharide (LPS) to enhance induction of differentiation. The nanoscaffolds were categorized by contact angle measurements and scanning electron microscopy. The MTT assay was used to analyze the rate of growth and proliferation of cells. Osteogenic differentiation of cultured MSCs was evaluated on nanofibers using common osteogenic markers, such as alkaline phosphatase activity, calcium mineral deposition, quantitative real-time polymerase chain reaction, and immunocytochemical analysis. Based on the in vitro results, primed MSCs with LPS on the PLLA nanoscaffold significantly enhanced the proliferation and osteogenesis of MSCs. Also, the combination of LPS and electrospun nanofibers can provide a new and suitable matrix to support stem cells’ differentiation for bone tissue engineering.  相似文献   
146.
147.
This work describes the performance of cytochrome c/nickel oxide nanoparticles/glassy carbon electrode, prepared by the electrochemical deposition of the nickel oxide nanoparticles (NiO NPs) on the glassy carbon (GC) electrode surface and the cytochrome c immobilization on the nickel oxide nanoparticle surfaces. An extensive sample examination with the help of the SEM and AFM presented the existence of different geometrical shapes of the nickel oxide particles. These geometrical structures could lead to the better immobilization of proteins on their surfaces. The resulting electrode displayed an excellent behavior for the redox of the cytochrome c. Also, the resulting heme protein exhibited a direct electrical contact with the electrode because of the structural alignment of the heme protein on the nanometer-scale nickel oxide surfaces. This method could be suitable for applications to nanofabricated devices. In the end, it was concluded that the cytochrome c could be tethered to the nanometer-scale nickel oxide surfaces.  相似文献   
148.
Breast cancer (BC) is an important cause of female cancer-related death. It has recently been demonstrated that metabolic disorders including lipid metabolism are a hallmark of cancer cells. Lipin-1 is an enzyme that displays phosphatidate phosphatase activity and regulates the rate-limiting step in the pathway of triglycerides and phospholipids synthesis. The objective of this study was to evaluate lipin-1 expression, its prognostic significance, and its correlation with p53 tumor suppressor in patients with BC. In this study, 55 pairs of fresh samples of BC and adjacent noncancerous tissue were used to analyze lipin-1, using quantitative real-time polymerase chain reaction and immunohistochemistry (IHC) staining. The expression of other clinicopathological variables and p53 was also examined using IHC technique. The cell migration was studied in MCF-7 and MDA-MB231 cells following the inhibition of lipin-1 by propranolol. Our results show that the relative expression of lipin-1 messenger RNA was significantly higher in BC tissues compared with the adjacent normal tissue and its inhibition reduced cell migration in cancer cells. This upregulation was negatively correlated with histological grade of tumor and p53 status (p = .001 and p = .034) respectively and positively correlated with the tumor size (p = .006). Our results also seem to indicate that the high lipin-1 expression is related to a good prognosis in patients with BC. The expression of lipin-1 may be considered as a novel independent prognostic factor. The inhibition of lipin-1 may also have therapeutic significance for patients with BC. The correlation between lipin-1 and p53 confirms the role of p53 in the regulation of lipid metabolism in cancer cells.  相似文献   
149.
Despite dramatic improvements in first-year patient and graft survival rates, chronic allograft dysfunction (CAD) remains the leading cause of late renal allograft loss, while current immunologic strategies have little effect on this condition. The renin–angiotensin system (RAS) plays an important role in progression of chronic renal disease. It was shown that plasminogen activator inhibitor-1 (PAI-1) functions in the RAS. This study investigates the possible links between angiotensinogen (AGT M235T), angiotensin-converting enzyme (ACE) and PAI-1 genotypes with CAD. Assessments of polymorphism were performed in 127 renal allograft recipients (77 with CAD and 50 with normal renal function). Fifty healthy subjects were also considered for comparison. Genotypes were determined using polymerase chain reaction (PCR) sequence-specific primers and PCR followed by restriction fragment length polymorphism analysis. Kidney recipients with CAD had significantly higher frequencies of the TT than the recipients without CAD (P < 0.05). The transplant recipients with CAD also had significantly higher frequencies of the DD genotype than those without CAD (P < 0.05). No significant differences were observed between the allelic and genotypic distributions of PAI-1 polymorphisms. Therefore, determination of AGT M235T and ACE genotypes prior to transplantation may be useful to identify patients who are at risk for chronic renal transplant dysfunction.  相似文献   
150.
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