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Credit Default Swaps and the Financial Crisis
This paper examines the role that credit default swaps (CDS) played in the run-up to and during the financial crisis that struck in 2007-2008. I examine the nature of CDS as well as their evolving uses preceding and during the crisis, such as in the case of synthetic collateralized debt obligations (CSOs). Through case studies, I also highlight several problems deriving from the pervasive and largely unregulated use of CDS, including counterpart and systemic risk as well as the empty creditor problem. Through these case studies and my analysis, I conclude that while CDS are meant to simply shift economic risk to those parties most willing and able to bear it without adding systemic risk to the economy, during the recent financial crisis the unregulated and pervasive CDS market actually contributed to systemic risk. Thus, I also propose possible solutions to address the problems associated with CDS
Quantitative evaluation of thermodynamic parameters for thermal back-reaction after mechanically induced fluorescence change
Kinetics of the thermal back-reaction of beta-diketonate boron difluoride complexes after mechanical perturbation were evaluated by fluorescence intensity changes for the first time, suggesting that the activation parameters of the reaction intermediates governed intermolecular interactions such as hydrogen bonding assisted by substituent groups
β-Diketonate, β-Ketoiminate, and β-Diiminate Complexes of Difluoroboron
A series of β-diketonate, keto(aryl)iminato, and β-bis(aryl)iminato complexes of difluoroboron, twenty in total, have been prepared to assess the impact of chelate ring and aniline substitution on the structural, electrochemical, and photophysical properties of these ubiquitous chelates. DFT (B3LYP/6-31G*) calculations supplemented the experimental results and both demonstrated that replacing oxygen with the more electron-donating aniline groups serves to only fine-tune the electronic properties because both the HOMO and LUMO energies are affected by such substitution. The electronic properties of all compounds are most greatly influenced by the nature of the substituents bound to the carbon portion of the chelate ring. Each difluoroboron complex undergoes two ligand-based, one-electron reductions where the first reduction potential becomes less favorable with increasing aniline substitution. Similarly, replacing oxygen with the more electron-donating aniline groups gives rise to slightly red-shifted absorption and emission processes. Substitution on the aniline ring has little, if any, influence on the electronic properties of the resultant complexes
Open lateral sphincterotomy - A method of choice in the treatment of chronic anal fissure. Indications and results
Aim: The key to the treatment of chronic anal fissures is the reduction of the abnormal values of anal resting pressure. The aim of the surgical treatment is to reduce the activity of the internal anal sphincter and to provide proper conditions for the fissure to cure, which can be achieved by internal sphincterotomy. In the modern surgical practice the internal sphincterotomy is performed away from the fissure, lateral of the last, using open or closed technique.Methods: In our study we performed open lateral internal sphincterotomy (OLST) of 82 patients with chronic anal fissure, compared to a control group of 231 patients, treated with different methods. Results: We didn`t register any recurrences in the sixth post-operative moth after OLST. 11% of patients with OLST were with registered incontinence after the sixth post-operative month compared with 4.4% in non-OLST patients. The data was statistically significant (p=0.032)Conclusion: Choosing an OLST as a method for treatment of chronic anal fissure requires careful selection of patients. It is not recommended for patients with a risk of incontinence like those with a previous birth trauma, age beyond 60 years, previous ano-rectal operations, neurological diseases and low values in anal resting pressure.Aim: The key to the treatment of chronic anal fissures is the reduction of the abnormal values of anal resting pressure. The aim of the surgical treatment is to reduce the activity of the internal anal sphincter and to provide proper conditions for the fissure to cure, which can be achieved by internal sphincterotomy. In the modern surgical practice the internal sphincterotomy is performed away from the fissure, lateral of the last, using open or closed technique.Methods: In our study we performed open lateral internal sphincterotomy (OLST) of 82 patients with chronic anal fissure, compared to a control group of 231 patients, treated with different methods. Results: We didn`t register any recurrences in the sixth post-operative moth after OLST. 11% of patients with OLST were with registered incontinence after the sixth post-operative month compared with 4.4% in non-OLST patients. The data was statistically significant (p=0.032)Conclusion: Choosing an OLST as a method for treatment of chronic anal fissure requires careful selection of patients. It is not recommended for patients with a risk of incontinence like those with a previous birth trauma, age beyond 60 years, previous ano-rectal operations, neurological diseases and low values in anal resting pressure
In Vivo Length Changes Between the Attachments of the Medial Patellofemoral Complex Fibers in Knees With Anatomic Risk Factors for Patellar Instability
Background: Medial patellofemoral complex (MPFC) reconstruction plays an important role in the surgical treatment of patellar instability. Anatomic reconstruction is critical in re-creating the native function of the ligament, which includes minimizing length changes that occur in early flexion. Anatomic risk factors for patellar instability such as trochlear dysplasia, patella alta, and increased tibial tuberosity to trochlear groove (TT-TG) distance have been shown to influence the function of the MPFC graft in cadaveric studies, but the native length change patterns of the MPFC fibers in knees with anatomic risk factors have not been described. Purpose: To describe the in vivo length changes of the MPFC fibers in knees with anatomic risk factors for patellar instability and identify the optimal attachment sites for MPFC reconstruction. Study Design: Controlled laboratory study. Methods: Dynamic computed tomography imaging was performed on the asymptomatic knee in patients with contralateral patellar instability. Three-dimensional digital knee models were created to assess knees between 0° and 50° of flexion in 10° increments. MPFC fiber lengths were calculated at each flexion angle between known anatomic attachment points on the extensor mechanism (quadriceps tendon, MPFC midpoint [M], and patella) and femur (1, 2, and 3, representing the proximal to distal femoral footprint). Changes in MPFC fiber length were compared for each condition and assessed for their relationships to morphologic risk factors (trochlear depth, Caton Deschamps Index [CDI], and TT-TG distance). Results: In 22 knees, native MPFC fibers were found to be longer at 0° than at 20° to 50° of flexion. Length changes observed between 0° and 50° increased with the number of risk factors present. In the central fibers of the MPFC (M-2), 1.7% ± 3.1% length change was noted in knees with no anatomic risk factors, which increased to 5.6% ± 4.6%, 17.0% ± 6.4%, and 26.7% ± 6.8% in the setting of 1, 2, and 3 risk factors, respectively. Nonanatomic patella-based attachments were more likely to demonstrate unfavorable length change patterns, in which length was greater at 50° than 0°. In patellar attachments, an independent relationship was found between increasing length changes and TT-TG distance, while in quadriceps tendon attachments, a trend toward a negative relationship between length changes and CDI was noted. All configurations demonstrated a strong relationship between percentage change in length and number of morphologic risk factors present, with the greatest influence found in patella-based attachments. Conclusion: The MPFC fibers demonstrated increased length changes in knees when a greater number of morphological risk factors for patellar instability were present, which worsened in the setting of nonanatomic configurations. This suggests that the function of the intact MPFC in patients with anatomic risk factors may not reflect previously described findings in anatomically normal knees. Further studies are needed to understand the pathoanatomy related to these changes, as well as the implications for graft placement and assessment of length changes during MPFC reconstruction techniques. Clinical Relevance: MPFC length change patterns vary based on the number of morphologic risk factors for patellar instability present and should be considered during reconstructive procedures.</p
Behaver and risk factors for health of operators employed in oil production and preparation enterprises
Objective: to evaluate the behavioral risk factors of the workers of the primary oil refining workshop with the aim of using them as a tool for substantiating management decisions and forming vectors of preventive measures.Materials and methods: the method of active survey investigated the prevalence of behavioral risk factors among operators in two age groups (20 – 35 and 36 – 60 years old).Results: the main vectors of behavioral risks for operators of different age groups were established: lack of motor activity, smoking, low medical activity, low perception of behavioral risks. Violations of lifestyle are predominantly combined (violations by 2 – 4 indicators). For older operators are more characterized by low motor and medical activity, disturbances in diet, an overestimation of the degree of influence of environmental and occupational factors on health when the significance of individual behavior is underestimated.Conclusions: Social policy at the enterprise should take into account the main vectors of behavioral risks, lower motivation and the implementation of a healthy style of behavior typical of older workers
Deroofing - a method of choice in the treatment of suppurative perineal hidradenitis
Purpose: Suppurative hidradenitis is a chronic relapsing inflammatory disease that affects the apocrine sweat glands. Therefore, it is most often located in the axilla, groin and perianal area. Usually, people of working age affected. Perineal and perianal locations cover about 37% of the total morbidity rate and are more common in males. The objective of this study was to share our experience with the application of deroofing for the treatment of purulent perineal hidradenitis.Material and methods: This prospective interventional study covered 13 patients with suppurative fistulasing hidradenitis of perineum treated in Division of Coloproctology and Septic Surgery, Georgi Stranski University Hospital of Pleven for the period from 2008 till 2013.Results: The interval between the occurrence of disease and its surgical treatment was very long - from two to 36 years (average of 9,2 years). It resulted from the progression of the disease with enlarged soft tissue involvement. Sometimes, the disease was complicated by chroniosepsis. The average hospital stay was 13,5-day long. Operative wounds healed secondarily at an average of about 30 days. The patients were followedup for six months, one year and two years. Two patients with relapses on the sixth postoperative month were hospitalized again. The surgical intervention warranted good results.Conclusion: Treatment of suppurative hidradenitis of the perineum is complex, both in terms of local status and systematic violations resulting in chronic infection. There are numerous surgical techniques for treating this pathology. The advantages of deroofing are the following: minimal trauma to the patient, application by using local anesthesia at the early stage in order to minimize hospital stay, no need of special equipment, a lower recurrence rate than the other methods and formation of aesthetically acceptable scar
Elastomeric cardiopatch scaffold for myocardial repair and ventricular support
[EN] OBJECTIVES: Prevention of postischaemic ventricular dilatation progressing towards pathological remodelling is necessary to decrease ventricular wall deterioration. Myocardial tissue engineering may play a therapeutic role due to its capacity to replace the extracellular matrix, thereby creating niches for cell homing. In this experimental animal study, a biomimetic cardiopatch was created with elastomeric scaffolds and nanotechnologies.
METHODS: In an experimental animal study in 18 sheep, a cardiopatch was created with adipose tissue-derived progenitor cells seeded into an engineered bioimplant consisting of 3-dimensional bioabsorbable polycaprolactone scaffolds filled with a peptide hydrogel (PuraMatrix (TM)). This patch was then transplanted to cover infarcted myocardium. Non-absorbable poly(ethyl) acrylate polymer scaffolds were used as controls.
RESULTS: Fifteen sheep were followed with ultrasound scans at 6 months, including echocardiography scans, tissue Doppler and spectral flow analysis and speckle-tracking imaging, which showed a reduction in longitudinal left ventricular deformation in the cardiopatch-treated group. Magnetic resonance imaging (late gadolinium enhancement) showed reduction of infarct size relative to left ventricular mass in the cardiopatch group versus the controls. Histopathological analysis at 6 months showed that the cardiopatch was fully anchored and integrated to the infarct area with minimal fibrosis interface, thereby promoting angiogenesis and migration of adipose tissue-derived progenitor cells to surrounding tissues.
CONCLUSIONS: This study shows the feasibility and effectiveness of a cardiopatch grafted onto myocardial infarction scars in an experimental animal model. This treatment decreased fibrosis, limited infarct scar expansion and reduced postischaemic ventricular deformity. A capillary network developed between our scaffold and the heart. The elastomeric cardiopatch seems to have a positive impact on ventricular remodelling and performance in patients with heart failure.The RECATABI Project (Regeneration of Cardiac Tissue Assisted by Bioactive Implants) was financially supported by the 7th Framework Programme (FP7) of the European Commission. Project ID: 229239. Funded under FP7-NMP and the European Regional Development Fund (FEDER Spain).Chachques, JC.; Lila, N.; Soler Botija, C.; Martínez-Ramos, C.; Vallés Lluch, A.; Autret, G.; Perier, M.... (2020). Elastomeric cardiopatch scaffold for myocardial repair and ventricular support. European Journal of Cardio-Thoracic Surgery. 57(3):545-555. https://doi.org/10.1093/ejcts/ezz252S545555573Madonna, R., Van Laake, L. W., Botker, H. E., Davidson, S. M., De Caterina, R., Engel, F. B., … Sluijter, J. P. G. (2019). ESC Working Group on Cellular Biology of the Heart: position paper for Cardiovascular Research: tissue engineering strategies combined with cell therapies for cardiac repair in ischaemic heart disease and heart failure. Cardiovascular Research, 115(3), 488-500. doi:10.1093/cvr/cvz010Nielsen, S. H., Mouton, A. J., DeLeon-Pennell, K. Y., Genovese, F., Karsdal, M., & Lindsey, M. L. (2019). Understanding cardiac extracellular matrix remodeling to develop biomarkers of myocardial infarction outcomes. Matrix Biology, 75-76, 43-57. doi:10.1016/j.matbio.2017.12.001Spinale, F. G., Frangogiannis, N. G., Hinz, B., Holmes, J. W., Kassiri, Z., & Lindsey, M. L. (2016). Crossing Into the Next Frontier of Cardiac Extracellular Matrix Research. 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Three-Dimensional Cultures of Human Subcutaneous Adipose Tissue-Derived Progenitor Cells Based on RAD16-I Self-Assembling Peptide. Tissue Engineering Part C: Methods, 22(2), 113-124. doi:10.1089/ten.tec.2015.0270Martínez-Ramos, C., Rodríguez-Pérez, E., Garnes, M. P., Chachques, J. C., Moratal, D., Vallés-Lluch, A., & Monleón Pradas, M. (2014). Design and Assembly Procedures for Large-Sized Biohybrid Scaffolds as Patches for Myocardial Infarct. Tissue Engineering Part C: Methods, 20(10), 817-827. doi:10.1089/ten.tec.2013.0489Biswas, M., Sudhakar, S., Nanda, N. C., Buckberg, G., Pradhan, M., Roomi, A. U., … Houle, H. (2013). Two- and Three-Dimensional Speckle Tracking Echocardiography: Clinical Applications and Future Directions. Echocardiography, 30(1), 88-105. doi:10.1111/echo.12079Dorsey, S. M., McGarvey, J. R., Wang, H., Nikou, A., Arama, L., Koomalsingh, K. J., … Burdick, J. A. (2015). 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Bioluminescence imaging of cardiomyogenic and vascular differentiation of cardiac and subcutaneous adipose tissue-derived progenitor cells in fibrin patches in a myocardium infarct model. International Journal of Cardiology, 169(4), 288-295. doi:10.1016/j.ijcard.2013.09.013Chachques, J. C., Trainini, J. C., Lago, N., Cortes-Morichetti, M., Schussler, O., & Carpentier, A. (2008). Myocardial Assistance by Grafting a New Bioartificial Upgraded Myocardium (MAGNUM Trial): Clinical Feasibility Study. The Annals of Thoracic Surgery, 85(3), 901-908. doi:10.1016/j.athoracsur.2007.10.052Lee, H., Ahn, S., Bonassar, L. J., & Kim, G. (2012). Cell(MC3T3-E1)-Printed Poly(ϵ-caprolactone)/Alginate Hybrid Scaffolds for Tissue Regeneration. Macromolecular Rapid Communications, 34(2), 142-149. doi:10.1002/marc.201200524Strub, M., Van Bellinghen, X., Fioretti, F., Bornert, F., Benkirane-Jessel, N., Idoux-Gillet, Y., … Clauss, F. (2018). Maxillary Bone Regeneration Based on Nanoreservoirs Functionalizedε-Polycaprolactone Biomembranes in a Mouse Model of Jaw Bone Lesion. BioMed Research International, 2018, 1-12. doi:10.1155/2018/7380389Rohman, G., Huot, S., Vilas-Boas, M., Radu-Bostan, G., Castner, D. G., & Migonney, V. (2015). The grafting of a thin layer of poly(sodium styrene sulfonate) onto poly(ε-caprolactone) surface can enhance fibroblast behavior. Journal of Materials Science: Materials in Medicine, 26(7). doi:10.1007/s10856-015-5539-7Spadaccio, C., Nappi, F., De Marco, F., Sedati, P., Taffon, C., Nenna, A., … Rainer, A. (2017). Implantation of a Poly-l-Lactide GCSF-Functionalized Scaffold in a Model of Chronic Myocardial Infarction. Journal of Cardiovascular Translational Research, 10(1), 47-65. doi:10.1007/s12265-016-9718-9Monnet, E., & Chachques, J. C. (2005). Animal Models of Heart Failure: What Is New? 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Cor Triatriatum Sinister diagnosed in adult life with three dimensional transesophageal echocardiography
<p>Abstract</p> <p>Background</p> <p>Cor triatriatum is a very rare congenital abnormality, usually symptomatic during childhood, diagnosis in adult age is less common.</p> <p>Case Presentation</p> <p>We report the case of a 40 years old woman referred to our hospital for atrial flutter ablation, transthoracic cardiac bidimensional echocardiography showed an abnormal membrane bisecting the left atrium, the diagnosis of cor triatriatum was fully made via three dimensional transesophageal echocardiography. More interstingly three other cardiac anomalies were associated: ostium secundum atrial septal defect, dilated coronary sinus due probably to persistent left superior vena cava and normally functioning bicuspid aortic valve.</p> <p>Conclusions</p> <p>Cor triatriatum sinister in adult life is important to recognize because it may be easily surgically correctable when hemodynamically significant. Three Dimensional transesophageal echocardiography is a minimally invasive and highly sensitive diagnostic modality.</p
Androgen receptor targets NFKB and TSPI to suppress prostate tumor growth in vivo
The androgen role in the maintenance of prostate epithelium is subject to conflicting opinions. While androgen ablation drives the regression of normal and cancerous prostate, testosterone may cause both proliferation and apoptosis. Several investigators note decreased proliferation and stronger response to chemotherapy of the prostate cancer cells stably expressing androgen receptor (AR), however no mechanistic explanation was offered. In this paper we demonstrate in vivo anti-tumor effect of the AR on prostate cancer growth and identify its molecular mediators. We analyzed the effect of AR on the tumorigenicity of prostate cancer cells. Unexpectedly, the AR-expressing cells formed tumors in male mice at a much lower rate than the AR-negative controls. Moreover, the AR-expressing tumors showed decreased vascularity and massive apoptosis. AR expression lowered the angiogenic potential of cancer cells, by increasing secretion of an anti-angiogenic protein, thrombospondin-1. AR activation caused a decrease in RelA, a subunit of the pro-survival transcription factor NF kappa B, reduced its nuclear localization and transcriptional activity. This, in turn, diminished the expression of its anti-apoptotic targets, Bcl-2 and IL-6. Increased apoptosis within AR-expressing tumors was likely due to the NF kappa B suppression, since it was restricted to the cells lacking nuclear (active) NF kappa B. Thus we for the first time identified combined decrease of NF kappa B and increased TSP1 as molecular events underlying the AR anti-tumor activity in vivo. Our data indicate that intermittent androgen ablation is preferable to continuous withdrawal, a standard treatment for early-stage prostate cancer. (C) 2007 Wiley-Liss, Inc.The androgen role in the maintenance of prostate epithelium is subject to conflicting opinions. While androgen ablation drives the regression of normal and cancerous prostate, testosterone may cause both proliferation and apoptosis. Several investigators note decreased proliferation and stronger response to chemotherapy of the prostate cancer cells stably expressing androgen receptor (AR), however no mechanistic explanation was offered. In this paper we demonstrate in vivo anti-tumor effect of the AR on prostate cancer growth and identify its molecular mediators. We analyzed the effect of AR on the tumorigenicity of prostate cancer cells. Unexpectedly, the AR-expressing cells formed tumors in male mice at a much lower rate than the AR-negative controls. Moreover, the AR-expressing tumors showed decreased vascularity and massive apoptosis. AR expression lowered the angiogenic potential of cancer cells, by increasing secretion of an anti-angiogenic protein, thrombospondin-1. AR activation caused a decrease in RelA, a subunit of the pro-survival transcription factor NF kappa B, reduced its nuclear localization and transcriptional activity. This, in turn, diminished the expression of its anti-apoptotic targets, Bcl-2 and IL-6. Increased apoptosis within AR-expressing tumors was likely due to the NF kappa B suppression, since it was restricted to the cells lacking nuclear (active) NF kappa B. Thus we for the first time identified combined decrease of NF kappa B and increased TSP1 as molecular events underlying the AR anti-tumor activity in vivo. Our data indicate that intermittent androgen ablation is preferable to continuous withdrawal, a standard treatment for early-stage prostate cancer. (C) 2007 Wiley-Liss, Inc
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