240 research outputs found
Structure of the hepatitis C virus IRES bound to the human 80S ribosome: Remodeling of the HCV IRES
Финансы
Дисциплина «Финансы» относится к циклу дисциплин профессиональной подготовки по специальности 072 «Финансы, банковское дело и страхование». Научное понимание проблем финансовой системы государства, финансовой политики и финансового механизма, налоговой системы и налоговой политики, развития финансового рынка, финансов предприятий и финансов международных организаций, обеспечение финансовой безопасности государства являются необходимым элементом становления профессиональных экономических знаний студентов. Современный специалист в области финансов способен достичь успеха в своей профессиональной деятельности только при наличии четкого представления сущности финансов и их функций, финансового механизма, функционирования финансового рынка, организации фискального оборота; знания основных принципов построения финансовых систем развитых стран; понимания влияния денежно-кредитной и фискально-бюджетной политики на экономическое развитие государства. Учитывая это, учебным планом по специальности 072 «Финансы, банковское дело и страхование» при изучении дисциплины «Финансы» предусмотрено выполнение курсовой работы. Курсовая работа является научной разработкой определенной темы исследования в процессе подготовки специалиста по финансам. Благодаря курсовому проектированию студент учится систематизировать полученные теоретические знания по дисциплине и получать навыки экономических расчетов для принятия управленческих решений. Преподаватель проверяет качество этих знаний, выявляет уровень общенаучной и специальной подготовки студента, его способность применять полученные знания для решения конкретных проблем, склонность к анализу и самостоятельному обобщению материала по теме исследования. Творческий подход к выполнению курсовой работы способствует формированию у студентов навыков научных исследований и прикладных разработок. Выполнение работы важно для подготовки докладов студенческих научных работ, а также может быть использовано в ходе дипломного проектирования
Calcaneal nonunion: three cases and a review of the literature
The long-term follow-up of intra-articular calcaneal fractures is often accompanied by complications. Frequently occurring are arthrosis, arthrofibrosis of the subtalar joint, and malunion. Uncommon is the calcaneal nonunion. A total of three cases is presented in this report, including a review of the literature. The occurrence of a nonunion appears to be more common after conservative treatment, but the pathophysiology remains unclear, however smoking may play a role
Closed reduction and percutaneus Kirschner wire fixation for the treatment of dislocated calcaneal fractures: surgical technique, complications, clinical and radiological results after 2–10 years
Mechanical properties during healing of Achilles tendon ruptures to predict final outcome: A pilot Roentgen stereophotogrammetric analysis in 10 patients
<p>Abstract</p> <p>Background</p> <p>There are presently few methods described for in vivo monitoring of the mechanics of healing human tendon ruptures, and no methods for prediction of clinical outcome. We tested if Roentgen stereophotogrammetric analysis (RSA) can be used to follow the restoration of mechanical properties during healing of ruptured Achilles tendons, and if early measurements can predict clinical results.</p> <p>Methods</p> <p>Achilles tendon repair was studied with RSA in 10 patients with a total rupture. Tantalum beads were implanted in conjunction with surgical repair. The patients were evaluated at 6, 12 and 18 weeks, and after 1 year. RSA was performed with two different mechanical loadings, and the strain induced by increasing load was measured. The transverse area was determined by ultrasound. CT scan at 12 weeks confirmed that the tantalum beads were located within the tendons. Functional testing was done after 1 year. A heel raise index was chosen as primary clinical outcome variable.</p> <p>Results</p> <p>The strain was median 0.90, 0.32 and 0.14 percent per 100 N tendon force at 6 weeks, 18 weeks and one year respectively. The error of measurement was 0.04 percent units at 18 weeks. There was a large variation between patients, which appears to reflect biological variation. From 6 to 18 weeks, there was a negative correlation between increase in transverse area and increase in material properties, suggesting that healing is regulated at the organ level, to maximize stiffness. Modulus of elasticity during this time correlated with a heel raise index at one year (Rho = 0.76; p = 0.02).</p> <p>Conclusion</p> <p>We conclude that the RSA method might have potential for comparing different treatments of Achilles tendon ruptures.</p
The abundance of RNPS1, a protein component of the exon junction complex, can determine the variability in efficiency of the Nonsense Mediated Decay pathway
Nonsense-mediated mRNA decay (NMD) is a molecular pathway of mRNA surveillance that ensures rapid degradation of mRNAs containing premature translation termination codons (PTCs) in eukaryotes. NMD has been shown to also regulate normal gene expression and thus emerged as one of the key post-transcriptional mechanisms of gene regulation. Recently, NMD efficiency has been shown to vary between cell types and individuals thus implicating NMD as a modulator of genetic disease severity. We have now specifically analysed the molecular mechanism of variable NMD efficiency and first established an assay system for the quantification of NMD efficiency, which is based on carefully validated cellular NMD target transcripts. In a HeLa cell model system, NMD efficiency is shown to be remarkably variable and to represent a stable characteristic of different strains. In one of these strains, low NMD efficiency is shown to be functionally related to the reduced abundance of the exon junction component RNPS1. Furthermore, restoration of functional RNPS1 expression, but not of NMD-inactive mutant proteins, also restores efficient NMD in this model. We conclude that cellular concentrations of RNPS1 can modify NMD efficiency and propose that cell type specific co-factor availability represents a novel principle that controls NMD
Effects of a contoured articular prosthetic device on tibiofemoral peak contact pressure: a biomechanical study
Many middle-aged patients are affected by localized cartilage defects that are neither appropriate for primary, nor repeat biological repair methods, nor for conventional arthroplasty. This in vitro study aims to determine the peak contact pressure in the tibiofemoral joint with a partial femoral resurfacing device (HemiCAP®, Arthrosurface Inc., Franklin, MA, USA). Peak contact pressure was determined in eight fresh-frozen cadaveric specimens using a Tekscan sensor placed in the medial compartment above the menisci. A closed loop robotic knee simulator was used to test each knee in static stance positions (5°/15°/30°/45°) with body weight ground reaction force (GRF), 30° flexion with twice the body weight (2tBW) GRF and dynamic knee-bending cycles with body weight GRF. The ground reaction force was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles. Each specimen was tested under four different conditions: Untreated, flush HemiCAP® implantation, 1-mm proud implantation and 20-mm defect. A paired sampled t test to compare means (significance, P ≤ 0.05) was used for statistical analysis. On average, no statistically significant differences were found in any testing condition comparing the normal knee with flush device implantation. With the 1-mm proud implant, statistically significant increase of peak contact pressures of 217% (5° stance), 99% (dynamic knee bending) and 90% (30° stance with 2tBW) compared to the untreated condition was seen. No significant increase of peak contact pressure was evaluated with the 20-mm defect. The data suggests that resurfacing with the HemiCAP® does not lead to increased peak contact pressure with flush implantation. However, elevated implantation results in increased peak contact pressure and might be biomechanically disadvantageous in an in vivo application
Normalized long read RNA sequencing in chicken reveals transcriptome complexity similar to human
Background: Despite the significance of chicken as a model organism, our understanding of the chicken transcriptome is limited compared to human. This issue is common to all non-human vertebrate annotations due to the difficulty in transcript identification from short read RNAseq data. While previous studies have used single molecule long read sequencing for transcript discovery, they did not perform RNA normalization and 5'-cap selection which may have resulted in lower transcriptome coverage and truncated transcript sequences. Results: We sequenced normalised chicken brain and embryo RNA libraries with Pacific Bioscience Iso-Seq. 5' cap selection was performed on the embryo library to provide methodological comparison. From these Iso-Seq sequencing projects, we have identified 60 k transcripts and 29 k genes within the chicken transcriptome. Of these, more than 20 k are novel lncRNA transcripts with ~3 k classified as sense exonic overlapping lncRNA, which is a class that is underrepresented in many vertebrate annotations. The relative proportion of alternative transcription events revealed striking similarities between the chicken and human transcriptomes while also providing explanations for previously observed genomic differences. Conclusions: Our results indicate that the chicken transcriptome is similar in complexity compared to human, and provide insights into other vertebrate biology. Our methodology demonstrates the potential of Iso-Seq sequencing to rapidly expand our knowledge of transcriptomics
microRNA-Mediated Messenger RNA Deadenylation Contributes to Translational Repression in Mammalian Cells
Animal microRNAs (miRNAs) typically regulate gene expression by binding to partially complementary target sites in the 3′ untranslated region (UTR) of messenger RNA (mRNA) reducing its translation and stability. They also commonly induce shortening of the mRNA 3′ poly(A) tail, which contributes to their mRNA decay promoting function. The relationship between miRNA-mediated deadenylation and translational repression has been less clear. Using transfection of reporter constructs carrying three imperfectly matching let-7 target sites in the 3′ UTR into mammalian cells we observe rapid target mRNA deadenylation that precedes measureable translational repression by endogenous let-7 miRNA. Depleting cells of the argonaute co-factors RCK or TNRC6A can impair let-7-mediated repression despite ongoing mRNA deadenylation, indicating that deadenylation alone is not sufficient to effect full repression. Nevertheless, the magnitude of translational repression by let-7 is diminished when the target reporter lacks a poly(A) tail. Employing an antisense strategy to block deadenylation of target mRNA with poly(A) tail also partially impairs translational repression. On the one hand, these experiments confirm that tail removal by deadenylation is not strictly required for translational repression. On the other hand they show directly that deadenylation can augment miRNA-mediated translational repression in mammalian cells beyond stimulating mRNA decay. Taken together with published work, these results suggest a dual role of deadenylation in miRNA function: it contributes to translational repression as well as mRNA decay and is thus critically involved in establishing the quantitatively appropriate physiological response to miRNAs
Mid-portion Achilles tendinopathy: why painful? An evidence-based philosophy
Chronic mid-portion Achilles tendinopathy is generally difficult to treat as the background to the pain mechanisms has not yet been clarified. A wide range of conservative and surgical treatment options are available. Most address intratendinous degenerative changes when present, as it is believed that these changes are responsible for the symptoms. Since up to 34% of asymptomatic tendons show histopathological changes, we believe that the tendon proper is not the cause of pain in the majority of patients. Chronic painful tendons show the ingrowth of sensory and sympathetic nerves from the paratenon with release of nociceptive substances. Denervating the Achilles tendon by release of the paratenon is sufficient to cause pain relief in the majority of patients. This type of treatment has the additional advantage that it is associated with a shorter recovery time when compared with treatment options that address the tendon itself. An evidence-based philosophy on the cause of pain in chronic mid-portion Achilles tendinopathy is presented
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