976 resultados para mortality from egg to adult


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Dengue is a mosquito-borne viral infection that in recent decades has become a major international public health concern. Epidemic dengue fever reemerged in Brazil in 1981. Since 1990 more than one dengue virus serotype has been circulating in this tropical country and increasing rates of dengue hemorrhagic fever and dengue shock syndrome have been detected every year. Some evidence supports the association between the introduction of a new serotype and/or genotype in a region and the appearance of dengue hemorrhagic fever. In order to study the evolutionary relationships and possible detection of the introduction of new dengue virus genotypes in Brazil in the last years, we analyzed partial nucleotide sequences of 52 Brazilian samples of both dengue type 1 and dengue type 2 isolated from 1988 to 2001 from highly endemic regions. A 240-nucleotide-long sequence from the envelope/nonstructural protein 1 gene junction was used for phylogenetic analysis. After comparing the nucleotide sequences originally obtained in this study to those previously studied by others, and analyzing the phylogenetic trees, we conclude that, after the initial introduction of the currently circulating dengue-1 and dengue-2 genotypes in Brazil, there has been no evidence of introduction of new genotypes since 1988. The increasing number of dengue hemorrhagic fever cases seen in Brazil in the last years is probably associated with secondary infections or with the introduction of new serotypes but not with the introduction of new genotypes.

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In contrast to most developed countries, most patients with primary hyperparathyroidism in Brazil are still symptomatic at diagnosis. However, we have been observing a change in this pattern, especially in the last few years. We evaluated 104 patients, 77 females and 27 males aged 11-79 years (mean: 54.4 years), diagnosed between 1985 and 2002 at a University Hospital. Diagnosis was made on the basis of clinical findings and of high total and/or ionized calcium levels, high or inappropriate levels of intact parathyroid hormone and of surgical findings in 80 patients. Patients were divided into three groups, i.e., patients diagnosed from 1985 to 1989, patients diagnosed from 1990 to 1994, and patients diagnosed from 1995 to 2002. The number of new cases diagnosed/year increased from 1.8/year in the first group to 6.0/year in the second group and 8.1/year in the third group. The first group comprised 9 patients (mean serum calcium ± SD, 13.6 ± 1.6 mg/dl), 8 of them (88.8%) defined as symptomatic. The second group comprised 30 patients (mean calcium ± SD, 12.2 ± 1.63 mg/dl), 22 of them defined as symptomatic (73.3%). The third group contained 65 patients (mean calcium 11.7 ± 1.1 mg/dl), 34 of them symptomatic (52.3%). Patients from the first group tended to be younger (mean ± SD, 43.0 ± 15 vs 55.1 ± 14.4 and 55.7 ± 17.3 years, respectively) and their mean serum calcium was significantly higher (P < 0.05). All of symptomatic patients independent of group had higher serum calcium levels (12.4 ± 1.53 mg/dl, N = 64) than asymptomatic patients (11.4 ± 1.0 mg/dl, N = 40). Our data showed an increase in the percentage of asymptomatic patients over the years in the number of primary hyperparathyroidism cases diagnosed. This finding may be due to an increased availability of diagnostic methods and/or to an increased awareness about the disease.

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Bone morphogenetic proteins (BMPs) are multi-functional growth factors belonging to the transforming growth factor ß superfamily. Family members are expressed during limb development, endochondral ossification, early fracture, and cartilage repair. The activity of BMPs was first identified in the 1960s but the proteins responsible for bone induction were unknown until the purification and cloning of human BMPs in the 1980s. To date, about 15 BMP family members have been identified and characterized. The signal triggered by BMPs is transduced through serine/threonine kinase receptors, type I and II subtypes. Three type I receptors have been shown to bind BMP ligands, namely: type IA and IB BMP receptors and type IA activin receptors. BMPs seem to be involved in the regulation of cell proliferation, survival, differentiation and apoptosis, but their hallmark is their ability to induce bone, cartilage, ligament, and tendon formation at both heterotopic and orthotopic sites. This suggests that, in the future, they may play a major role in the treatment of bone diseases. Several animal studies have illustrated the potential of BMPs to enhance spinal fusion, repair critical-size defects, accelerate union, and heal articular cartilage lesions. Difficulties in producing and purifying BMPs from bone tissue have prompted the attempts made by several laboratories, including ours, to express these proteins in the recombinant form in heterologous systems. This review focuses on BMP structure, molecular mechanisms of action and significance and potential applications in medical, dental and veterinary practice for the treatment of cartilage and bone-related diseases.

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Flavobacterium psychrophilum is the etiological agent of bacterial cold-water disease (BCWD) causing high fish mortalities and significant economic losses to the freshwater salmonid aquaculture industry around the world. Today BCWD outbreaks are mainly treated with environmentally hazardous antimicrobial agents and alternative preventative measures are urgently needed in order to ensure the well-being of animals and the sustainability of aquaculture. The diversity of pathogenic bacteria challenges the development of universal control strategies and in many cases the pathogen population structure, i.e. the total genetic diversity of the species must be taken into account. This work integrates the tools of modern molecular biology and conventional phenotypic microbiology to gain knowledge about the diversity and population structure of F. psychrophilum. The present work includes genetic characterization of a large collection of isolates collected from diverse origins and years, from aquaculture in a whole region including different countries, and provides the first international validation of a universal multilocus sequence typing (MLST) approach for unambiguous genetic typing of F. psychrophilum. Population structure analyses showed that the global F. psychrophilum population is subdivided into pathogenic species-specific clones, of which one particular genetic lineage, clonal complex CC-ST2, has been responsible for the majority of BCWD outbreaks in rainbow trout (Oncorhynchus mykiss) in European aquaculture facilities over several decades. Genotypic and phenotypic population heterogeneity affecting antimicrobial resistance in F. psychrophilum within BCWD outbreaks was discovered. Specific genotypes were associated with severe infections in farmed rainbow trout and Atlantic salmon (Salmo salar), and in addition to high adherence, antimicrobial resistance was strongly associated with outbreak strains. The study brought additional support for the hypothesis of an epidemic F. psychrophilum population structure, where recombination is an important force for the generation and maintenance of genetic diversity, and a significant contribution towards mapping the genetic diversity of this important fish pathogen. Evidence indicating dissemination of virulent strains with commercial movement of fish and fish products was strengthened.

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Background: Recent recommendations aim to improve cardiovascular health (CVH) by encouraging the general population to meet positive and modifiable ideal CVH metrics: not smoking, being physically active, and maintaining normal weight, blood pressure, blood glucose and total cholesterol levels and a healthy diet. Aims: The aim of the present study was to report the prevalence of ideal CVH in children and young adults and study the associations of CVH metrics with markers of subclinical atherosclerosis. Participants and methods: The present thesis is part of the Cardiovascular Risk in Young Finns Study (Young Finns Study). Data on associations of CVH metrics and subclinical atherosclerosis were available from 1,898 Young Finns Study participants. In addition, joint analyses were performed combining data from the International Childhood Cardiovascular Cohort (i3C) Consortium member studies from Australia and the USA. Results: None of the participants met all 7 CVH metrics and thus had ideal CVH in childhood and only 1% had ideal CVH as young adults. The number of CVH metrics present in childhood and adulthood predicted lower carotid artery intima-media thickness, improved carotid artery distensibility and lower risk of coronary artery calcification. Those who improved their CVH status from childhood to adulthood had a comparable risk of subclinical atherosclerosis to participants who had always had a high CVH status. Conclusions: Ideal CVH proved to be rare among children and young adults. A higher number of ideal CVH metrics and improvement of CVH status between childhood and adulthood predicted a lower risk of subclinical atherosclerosis.

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Glucose enters eukaryotic cells via two types of membrane-associated carrier proteins, the Na+/glucose cotransporters (SGLT) and the facilitative glucose transporters (GLUT). The SGLT family consists of six members. Among them, the SGLT1 and SGLT2 proteins, encoded by the solute carrier genes SLC5A1 and SLC5A2, respectively, are believed to be the most important ones and have been extensively explored in studies focusing on glucose fluxes under both physiological and pathological conditions. This review considers the regulation of the expression of the SGLT promoted by protein kinases and transcription factors, as well as the alterations determined by diets of different compositions and by pathologies such as diabetes. It also considers congenital defects of sugar metabolism caused by aberrant expression of the SGLT1 in glucose-galactose malabsorption and the SGLT2 in familial renal glycosuria. Finally, it covers some pharmacological compounds that are being currently studied focusing on the interest of controlling glycemia by antagonizing SGLT in renal and intestinal tissues.

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Myosin Va functions as a processive, actin-based motor molecule highly enriched in the nervous system, which transports and/or tethers organelles, vesicles, and mRNA and protein translation machinery. Mutation of myosin Va leads to Griscelli disease that is associated with severe neurological deficits and a short life span. Despite playing a critical role in development, the expression of myosin Va in the central nervous system throughout the human life span has not been reported. To address this issue, the cerebellar expression of myosin Va from newborns to elderly humans was studied by immunohistochemistry using an affinity-purified anti-myosin Va antibody. Myosin Va was expressed at all ages from the 10th postnatal day to the 98th year of life, in molecular, Purkinje and granular cerebellar layers. Cerebellar myosin Va expression did not differ essentially in localization or intensity from childhood to old age, except during the postnatal developmental period. Structures resembling granules and climbing fibers in Purkinje cells were deeply stained. In dentate neurons, long processes were deeply stained by anti-myosin Va, as were punctate nuclear structures. During the first postnatal year, myosin Va was differentially expressed in the external granular layer (EGL). In the EGL, proliferating prospective granule cells were not stained by anti-myosin Va antibody. In contrast, premigratory granule cells in the EGL stained moderately. Granule cells exhibiting a migratory profile in the molecular layer were also moderately stained. In conclusion, neuronal myosin Va is developmentally regulated, and appears to be required for cerebellar function from early postnatal life to senescence.

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Metastasis is the main cause of death among cancer patients. In order to initiate the metastatic cascade cancer cells have to undergo epithelial-to-mesenchymal transition (EMT). In EMT epithelial cells lose their cell-cell and cell-extracellular matrix (ECM) contacts and become more motile. The expression of the transcription factor Slug and of the mesenchymal intermediate filament vimentin is induced during EMT. Vimentin is often overexpressed in malignant epithelial cancers but the functional role of vimentin remains incompletely understood. In addition, kinases such as AKT and ERK are known to be involved in the regulation of EMT and cancer cell motility but the mechanisms underlining their functions are often unclear. Integrins are heterodimeric receptors that attach cells to the surrounding tissue and participate in regulating cell migration and invasion. Changes in integrin activity are linked to increased cell motility and further cancer metastasis. The aim for my PhD studies was to investigate the role of cellular signalling pathways and vimentin in the regulation of cancer cell motility and EMT. Our results revealed that in prostate cancer the downregulation of AKT1 and AKT2, but not AKT3, induces activation of cell surface 1-integrins leading to enhanced cell adhesion, migration and invasion. In addition, our findings demonstrated a reciprocal regulatory interaction between vimentin and ERK2 facilitating ERK-mediated phosphorylation of Slug at serine-87 (S87) in breast cancer. Surprisingly, Slug S87 phosphorylation is dispensable for E-cadherin repression but essential for the induction of vimentin and Axl expression in early onset of EMT. Our findings reveal previously unknown mechanistic information of how prostate and breast cancer cell motility and disease progression is regulated

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TAVOITTEET: Tämän tutkielman tarkoitus on tarkastella eri toimialojen likviditeettitasoja vuosien 2007 ja 2013 välillä. Se tarkastelee myös kassanhallinnan ja likviditeetin kirjallisuutta, erilaisia likviditeettiä kuvaavia tunnuslukuja sekä asioita, joilla on vaikutusta likviditeettiin. Tämän lisäksi se tutkii informaatio ja kommunikaatio sektoria tarkemmin. DATA: Data on kerätty Orbis tietokannasta. Toimialakohtaiset keskiarvot on laskettu joko kappaleen 2 esittämillä kaavoilla tai noudettu suoraan tietokannasta. Hajonta kuvaajat on tehty Excelillä ja korrelaatio matriisi ja regressioanalyysit SAS EG:llä. TULOKSET: Tämä tutkimus esittää toimialakohtaiset keskiarvot liquidity ratiosta, solvency ratiosta sekä gearingista, kuten monista muista likviditeettiä kuvaavista tai siihen vaikuttavista tunnusluvuista. Tutkimus osoittaa, että keskimäärin likviditeetti ja maksuvalmius ovat säilyneet melko samana, mutta toimialakohtaiset muutokset ovat voimakkaita. IC sektorilla likviditeettiin vaikuttaa katetuotto, työntekijöiden määrä, liikevaihto, taseen määrä sekä maksuaika.