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Optimal Risk Transfers in Insurance Groups
Optimal risk transfers are derived within an insurance group consisting of two separate legal entities, operating under potentially different regulatory capital requirements and capital costs. Consistent with regulatory practice, capital requirements for each entity are computed by either a value-at-risk or an expected shortfall risk measure. The optimality criterion consists of minimising the risk-adjusted value of the total group liabilities, with valuation carried out using a cost-of-capital approach. The optimisation problems are analytically solved and it is seen that optimal risk transfers often involve the transfer of tail risk (unlimited reinsurance layers) to the more weakly regulated entity. We show that, in the absence of a capital requirement for the credit risk that specifically arises from the risk transfer, optimal risk transfers achieve capital efficiency at the cost of increasing policyholder deficit. However, when credit risk is properly reflected in the capital requirement, incentives for tail-risk transfers vanish and policyholder welfare is restored
Síndromes muy poco frecuentes
Dismorfología, Citogenética y Clínica: Resultados de estudios sobre los datos del ECEMCIn an attempt to facilitate the knowledge of the malformation syndromes that have very few frequencies to pediatricians and first health care physicians, particularly to those of rural areas, we have selected six new syndromes. As in previous years, the syndromes are selected from the ECEMC database registry. In this Boletín we include the following syndromes: Townes-Bröcks, MMT, Smith-Lemli-Opitz, Coffin-Siris, Espleno-gonadal fusion, and Silver-Russell syndromes. For each syndrome, we described the most important clinical characteristics, and the present knowledge of their causal factors.N
Epidermolysis bullosa (EB): Pathogenesis, clinical, diagnostic and genetic aspects, molecular basis, epidemiological aspects, management of patients with EB and translational implications of mutation analysis
Dismorfología, Citogenética y Clínica: Resultados de estudios sobre los datos del ECEMCUnder the term "Epidermolysis Bullosa" (EB), there is a heterogeneous group of vesicular disorders that are generally congenital and of
genetic origin, and affect skin and often mucosas. It is remarkable the extreme fragility of these epithelia; the vesicles arise spontaneously
as well as induced by even slight trauma or the influence of high temperatures. Their content is sero-hemorrhagic and in the scarring can
be very difficult. As a consecuence of the scarring processes, joint contractures and fusion of digits (pseudo-syndactyly) can occur.
Pathogenetically, EB is caused by abnormal blistering at the basement membrane zone in the dermal-epidermal attachment zone and its
surroundings. This is due to alterations in the attachment complexes, and some mutations have been identified in a total of 10 genes
expressed in such level. Four main types of EB can be distinguished (simple, junctional, dystrophic and hemidesmosomal), depending on
the level at which the cleavage that forms the bulla takes place, although about 30 subtypes have been described. The clinical characteristics
or optic microscopy are not adequate for diagnosis, and it is mandatory to perform electron microscopy, immunofluorescent and
immunohistochemical studies, as well as mutation analysis if available. Regarding the epidemiological aspects, in the Spanish Collaborative
Study of Congenital Malformations (ECEMC), since 1976 up to December 2004, a total of 2,204,264 liveborn infants were controlled and,
among them 27 cases have been identified, for a minimum frequency of 0.12 per 10,000 (95% confidence interval:0.08-0.18). It seems
generally accepted that the determination of the frequency of EB is subject to multiple biases and registration of cases is always incomplete.
We have also reviewed the issues related to management of EB patients by clinicians.N
Differential serotonin transport is linked to the rh5-HTTLPR in peripheral blood cells
The human serotonin transporter (SERT) gene possesses a 43-base pair (bp) insertion-deletion promoter polymorphism, the h5-HTTLPR. Genotype at this locus correlates with variation in anxiety-related personality traits and risk for major depressive disorder in many studies. Yet, the complex effects of the h5-HTTLPR, in combination with closely associated single-nucleotide polymorphisms (SNPs), continue to be debated. Moreover, although SERT is of high clinical significance, transporter function in vivo remains difficult to assess. Rhesus express a promoter polymorphism related to the h5-HTTLPR. The rh5-HTTLPR has been linked to differences in stress-related behavior and cognitive flexibility, although allelic variations in serotonin uptake have not been investigated. We studied the serotonin system as it relates to the 5-HTTLPR in rhesus peripheral blood cells. Sequencing of the rh5-HTTLPR revealed a 23-bp insertion, which is somewhat longer than originally reported. Consistent with previous reports, no SNPs in the rh5-HTTLPR and surrounding genomic regions were detected in the individuals studied. Reductions in serotonin uptake rates, cell surface SERT binding, and 5-hydroxyindoleacetic acid/serotonin ratios, but not SERT mRNA levels, were associated with the rh5-HTTLPR short allele. Thus, serotonin uptake rates are differentiable with respect to the 5-HTTLPR in an easily accessible native peripheral tissue. In light of these findings, we foresee that primary blood cells, in combination with high sensitivity functional measurements enabled by chronoamperometry, will be important for investigating alterations in serotonin uptake associated with genetic variability and antidepressant responsiveness in humans
Analyzing factors that influence the folk use and phytonomy of 18 medicinal plants in Navarra
BACKGROUND: This article analyzes whether the distribution or area of use of 18 medicinal plants is influenced by ecological and cultural factors which might account for their traditional use and/or phytonymy in Navarra. This discussion may be helpful for comparative studies, touching as it does on other ethnopharmacological issues: a) which cultural and ecological factors affect the selection of medicinal plants; b) substitutions of medicinal plants in popular medicine; c) the relation between local nomenclature and uses. To analyze these questions, this paper presents an example of a species used for digestive disorders (tea and camomile: Jasonia glutinosa, J. tuberosa, Sideritis hyssopifolia, Bidens aurea, Chamaemelum nobile, Santolina chamaecyparissus...), high blood pressure (Rhamnus alaternus, Olea europaea...) or skin diseases (Hylotelephium maximum, H. telephium, Anagallis arvensis, A. foemina). METHODS: Fieldwork began on January 2004 and continued until December 2006. During that time we interviewed 505 informants in 218 locations in Navarra. Information was collected using semi-structured ethnobotanical interviews, and we subsequently made maps using Arc-View 8.0 program to determine the area of use of each taxon. Each map was then compared with the bioclimatic and linguistic map of Navarra, using the soil and ethnographic data for the region, and with other ethnobotanical and ethnopharmacological studies carried out in Europe. RESULTS: The results clearly show that ecological and cultural factors influence the selection of medicinal plants in this region. Climate and substrate are the most important ecological factors that influence the distribution and abundance of plants, which are the biological factors that affect medicinal plant selection. CONCLUSION: The study of edaphological and climatological factors, on the one hand, and culture, on the other, can help us to understand why a plant is replaced by another one for the same purposes, either in the same or in a different area. In many cases, the cultural factor means that the use of a species is more widespread than its ecological distribution. This may also explain the presence of synonyms and polysemies which are useful for discussing ethnopharmacological data
Aetiology and risk factors of musculoskeletal disorders in physically active conscripts: a follow-up study in the Finnish Defence Forces
<p>Abstract</p> <p>Background</p> <p>Musculoskeletal disorders (MSDs) are the main reason for morbidity during military training. MSDs commonly result in functional impairment leading to premature discharge from military service and disabilities requiring long-term rehabilitation. The purpose of the study was to examine associations between various risk factors and MSDs with special attention to the physical fitness of the conscripts.</p> <p>Methods</p> <p>Two successive cohorts of 18 to 28-year-old male conscripts (<it>N </it>= 944, median age 19) were followed for six months. MSDs, including overuse and acute injuries, treated at the garrison clinic were identified and analysed. Associations between MSDs and risk factors were examined by multivariate Cox's proportional hazard models.</p> <p>Results</p> <p>During the six-month follow-up of two successive cohorts there were 1629 MSDs and 2879 health clinic visits due to MSDs in 944 persons. The event-based incidence rate for MSD was 10.5 (95% confidence interval (CI): 10.0-11.1) per 1000 person-days. Most MSDs were in the lower extremities (65%) followed by the back (18%). The strongest baseline factors associated with MSDs were poor result in the combined outcome of a 12-minute running test and back lift test (hazard ratio (HR) 2.9; 95% CI: 1.9-4.6), high waist circumference (HR 1.7; 95% CI: 1.3-2.2), high body mass index (HR 1.8; 95% CI: 1.3-2.4), poor result in a 12-minute running test (HR 1.6; 95% CI: 1.2-2.2), earlier musculoskeletal symptoms (HR 1.7; 95% CI: 1.3-2.1) and poor school success (educational level and grades combined; HR 2.0; 95% CI: 1.3-3.0). In addition, risk factors of long-term MSDs (≥10 service days lost due to one or several MSDs) were analysed: poor result in a 12-minute running test, earlier musculoskeletal symptoms, high waist circumference, high body mass index, not belonging to a sports club and poor result in the combined outcome of the 12-minute running test and standing long jump test were strongly associated with long-term MSDs.</p> <p>Conclusions</p> <p>The majority of the observed risk factors are modifiable and favourable for future interventions. An appropriate intervention based on the present study would improve both aerobic and muscular fitness prior to conscript training. Attention to appropriate waist circumference and body mass index would strengthen the intervention. Effective results from well-planned randomised controlled studies are needed before initiating large-scale prevention programmes in a military environment.</p
The content of endogenous hormones and sugars in the process of early somatic embryogenesis in the tree fern Cyathea delgadii Sternb.
Differential proteomic analysis of virus-enriched fractions obtained from plasma pools of patients with dengue fever or severe dengue
Preconditioning-induced ischemic tolerance: a window into endogenous gearing for cerebroprotection
Ischemic tolerance defines transient resistance to lethal ischemia gained by a prior sublethal noxious stimulus (i.e., preconditioning). This adaptive response is thought to be an evolutionarily conserved defense mechanism, observed in a wide variety of species. Preconditioning confers ischemic tolerance if not in all, in most organ systems, including the heart, kidney, liver, and small intestine. Since the first landmark experimental demonstration of ischemic tolerance in the gerbil brain in early 1990's, basic scientific knowledge on the mechanisms of cerebral ischemic tolerance increased substantially. Various noxious stimuli can precondition the brain, presumably through a common mechanism, genomic reprogramming. Ischemic tolerance occurs in two temporally distinct windows. Early tolerance can be achieved within minutes, but wanes also rapidly, within hours. Delayed tolerance develops in hours and lasts for days. The main mechanism involved in early tolerance is adaptation of membrane receptors, whereas gene activation with subsequent de novo protein synthesis dominates delayed tolerance. Ischemic preconditioning is associated with robust cerebroprotection in animals. In humans, transient ischemic attacks may be the clinical correlate of preconditioning leading to ischemic tolerance. Mimicking the mechanisms of this unique endogenous protection process is therefore a potential strategy for stroke prevention. Perhaps new remedies for stroke are very close, right in our cells
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