929 resultados para Somatic Embryogenesis


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Innumerous protocols, using the mouse embryonic stem (ES) cells as model for in vitro study of neurons functional properties and features, have been developed. Most of these protocols are short lasting, which, therefore, does not allow a careful analysis of the neurons maturation, aging, and death processes. We describe here a novel and efficient long-lasting protocol for in vitro ES cells differentiation into neuronal cells. It consists of obtaining embryoid bodies, followed by induction of neuronal differentiation with retinoic acid of nonadherent embryoid bodies (three-dimensional model), which further allows their adherence and formation of adherent neurospheres (AN, bi-dimensional model). The AN can be maintained for at least 12 weeks in culture under repetitive mechanical splitting, providing a constant microenvironment (in vitro niche) for the neuronal progenitor cells avoiding mechanical dissociation of AN. The expression of neuron-specific proteins, such as nestin, sox1, beta III-tubulin, microtubule-associated protein 2, neurofilament medium protein, Tau, neuronal nuclei marker, gamma-aminobutyric acid, and 5-hydroxytryptamine, were confirmed in these cells maintained during 3 months under several splitting. Additionally, expression pattern of microtubule-associated proteins, such as lissencephaly (Lis1) and nuclear distribution element-like (Ndel1), which were shown to be essential for differentiation and migration of neurons during embryogenesis, was also studied. As expected, both proteins were expressed in undifferentiated ES cells, AN, and nonrosette neurons, although presenting different spatial distribution in AN. In contrast to previous studies, using cultured neuronal cells derived from embryonic and adult tissues, only Ndel1 expression was observed in the centrosome region of early neuroblasts from AN. Mature neurons, obtained from ES cells in this work, display ionic channels and oscillations of membrane electrical potential typical of electrically excitable cells, which is a characteristic feature of the functional central nervous system (CNS) neurons. Taken together, our study demonstrated that AN are a long-term culture of neuronal cells that can be used to analyze the process of neuronal differentiation dynamics. Thus, the protocol described here provides a new experimental model for studying neurological diseases associated with neuronal differentiation during early development, as well as it represents a novel source of functional cells that can be used as tools for testing the effects of toxins and/or drugs on neuronal cells.

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Proline-rich peptides from Bothrops jararaca venom (Bj-PRO) were characterized based on the capability to inhibit the somatic angiotensin-converting enzyme. The pharmacological action of these peptides resulted in the development of Captopril, one of the best examples of a target-driven drug discovery for treatment of hypertension. However, biochemical and biological properties of Bj-PROs were not completely elucidated yet, and many recent studies have suggested that their activity relies on angiotensin-converting enzyme-independent mechanisms. Here, we show that Bj-PRO-7a (

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The biological activity of the proline rich decapeptde Bj PRO 10c a processing product of the C type natriuretic peptide precursor protein, expressed in the brain and the venom gland of the pit viper Bothrops jararaca, was originally attributed to the inhibition of the somatic angiotensm converting enzyme activity with subsequent ant hypertensive effect However recent results suggest broader biological activity may also be involved in the cardiovascular effects of this peptide Here we show that Bj PRO 10c enhances and sustains the generation of nitric made (NO) by regulating argininosuccinate synthase activity and thereby velocity of the citrulline NO cycle Bj PRO 10c-mediated effects not restricted to the cardiovascular system since NO production was also induced in cells of astroglial origin Bj PRO 10c was internalized by C6 astroglioma cells where it induces NO production and upregulation of the citrulline NO cycle cells in a dose dependent fashion In view of that, astroglial cells function as L arginine pool for NO production in neighboring neurons, we suggest a regulatory function for Bj PRO-10c on the metabolism of this gaseous neurotransmitter in the CNS Moreover, proliferation of astroglial cells was reduced in the presence of Bj PRO 10c however, cell death was not induced Since NO donors have been studied for the treatment of solid cancers Bj PRO 10c may serve as structural model for developing drugs to improve the effects of cancer therapy based on the peptide`s ability to augment NO production (C) 2010 Elsevier B V All rights reserved

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Background Depression symptomatology was assessed with the Beck Depression Inventory (BDI) in a sample of Jewish adolescents, in order to compare the frequency and severity of depression with non-Jewish adolescents as well as examine gender difference of the expression of depressive symptomatology. Method Subjects comprised 475 students from Jewish private schools, aged 13-17 years, who were compared with an age-matched non-Jewish sample (n = 899). Kendall`s definition was adopted to classify these adolescents according to level of depressive symptoms. The frequency of depression was calculated for ethnicity, gender and age strata. Discriminant analysis and principal component analysis were performed to assess the importance of depression-specific and non-specific items, along with the factor structure of the BDI, respectively. Results The overall mean score on the BDI in the Jewish and the non-Jewish sample was 9.0 (SD = 6.4) and 8.6 (SD = 7.2), respectively. Jewish girls and boys had comparable mean BDI scores, contrasting with non-Jewish sample, where girls complained more of depressive symptoms than boys (p < 0.001). The frequency of depression, adopting a BDI cutoff of 20, was 5.1% for the Jewish sample and 6.3% for the non-Jewish sample. The frequency of depression for Jewish girls and boys was 5.5% (SE = 1.4) and 4.6% (SE = 1.5), respectively. On the other hand, the frequency of depression for non-Jewish girls and boys was 8.4% (SE = 1.2) and 4.0% (SE = 1.0), respectively. The female/male ratio of frequency of BDI-depression was 1.2 in the Jewish sample, but non-Jewish girls were twice (2.1) as likely to report depression as boys. Discriminant analysis showed that the BDI highly discriminates depressive symptomatology among Jewish adolescents, and measured specific aspects of depression. Factor analysis revealed two meaningful factors for the total sample and each gender (cognitive-affective dimension and somatic dimension), evidencing a difference between Jewish boys and Jewish girls in the symptomatic expression of depression akin to non-Jewish counterparts. Conclusions Ethnic-cultural factor might play a role in the frequency, severity and symptomatic expression of depressive symptoms in Jewish adolescents. The lack of gender effect on depression, which might persist from adolescence to adulthood among Jewish people, should be investigated in prospective studies.

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Ticks are obligatory blood-feeding arthropods and important vectors of both human and animal disease agents. Besides its metabolic role, insulin signaling pathway (ISP) is widely described as crucial for vertebrate and invertebrate embryogenesis, development and cell survival. In such cascade, Phosphatidylinositol 3-OH Kinase (PI3K) is hierarchically located upstream Protein Kinase B (PKB). To study the insulin-triggered pathway and its possible roles during embryogenesis we used a culture of embryonic Rhipicephalus microplus cells (BME26). Exogenous insulin elevated cell glycogen content in the absence of fetal calf serum (FCS) when compared to cells without treatment. Moreover, in the presence of PI3K inhibitors (Wortmannin or LY294002) these effects were blocked. We observed an increase in the relative expression level of PI3K`s regulatory subunit (p85), as determined by qRT-PCR. In the presence of PI3K inhibitors these effects on transcription were also reversed. Additionally, treatment with Wortmannin increased the expression level of the insulin-regulated downstream target glycogen synthase kinase 3 beta (GSK3 beta). The p85 subunit showed elevated transcription levels in ovaries from fully engorged females, but was differentially expressed during tick embryogenesis. These results strongly suggest the presence of an insulin responsive machinery in BME26 cells, and its correlation with carbohydrate/glycogen metabolism also during embryogenesis. (C) 2009 Published by Elsevier Inc.

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In 2006, the first report of a nanostructured material as adjuvant was described establishing the effectiveness of the ordered mesoporous SBA-15 silica as an immune adjuvant. The present study evaluated the SBA-15 capacity to modulate the immune responsiveness of High and Low responder mice immunized with BSA encapsulated/adsorbed in SBA-15 by the intramuscular or oral route and the adjuvant effect was compared with the responsiveness induced by BSA in aluminum hydroxide salts or emulsified in Incomplete Freund adjuvant. These results demonstrate the ability of the non-toxic SBA-15 nanoparticles to increase the immunogenicity and repair the responsiveness of the constitutively low responder individuals inducing both the IgG2a and the IgG1 isotypes, independently of the immune cell committed and conditioning the low phenotype. This new adjuvant may reveal novel therapeutic targets for immune modulation and vaccine design. (C) 2010 Elsevier Ltd. All rights reserved.

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The first naturally occurring angiotensin-converting enzyme (ACE) inhibitors described are pyroglutamyl proline-rich oligopeptides, found in the venom of the viper Bothrops jararaca, and named as bradykinin-potentiating peptides (BPPs). Biochemical and pharmacological properties of these peptides were essential for the development of Captopril, the first active site-directed inhibitor of ACE, currently used for the treatment of human hypertension. However, a number of data have suggested that the pharmacological activity of BPPs could not only be explained by their inhibitory action on enzymatic activity of somatic ACE. In fact, we showed recently that the strong and long-lasting anti-hypertensive effect of BPP-10c [somatic ACE inhibition. On the other hand, nicotinic acetylcholine receptors expressed in blood vessels have been related to blood pressure regulation. Therefore, we have studied the effects of BPP-10c on acetylcholine receptor function in the PC12 pheochromocytoma cell line, which following induction to neuronal differentiation expresses most of the nicotinic receptor subtypes. BPP-10c did not induce receptor-mediated ion flux, nor potentiated carbamoylcholine-provoked receptor activity as determined by whole-cell recording. This peptide, however, alleviated MK-801-induced inhibition of nicotinic acetylcholine receptor activity. Although more data are needed for understanding the mechanism of the BPP-10c effect on nicotinic receptor activity and its relationship with the anti-hypertensive activity, this work reveals possible therapeutic applications for BPP-10c in establishing normal acetylcholine receptor activity. (C) 2008 Elsevier Inc. All rights reserved.

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Animal traits differ not only in mean, but also in variation around the mean. For instance, one sire’s daughter group may be very homogeneous, while another sire’s daughters are much more heterogeneous in performance. The difference in residual variance can partially be explained by genetic differences. Models for such genetic heterogeneity of environmental variance include genetic effects for the mean and residual variance, and a correlation between the genetic effects for the mean and residual variance to measure how the residual variance might vary with the mean. The aim of this thesis was to develop a method based on double hierarchical generalized linear models for estimating genetic heteroscedasticity, and to apply it on four traits in two domestic animal species; teat count and litter size in pigs, and milk production and somatic cell count in dairy cows. The method developed is fast and has been implemented in software that is widely used in animal breeding, which makes it convenient to use. It is based on an approximation of double hierarchical generalized linear models by normal distributions. When having repeated observations on individuals or genetic groups, the estimates were found to be unbiased. For the traits studied, the estimated heritability values for the mean and the residual variance, and the genetic coefficients of variation, were found in the usual ranges reported. The genetic correlation between mean and residual variance was estimated for the pig traits only, and was found to be favorable for litter size, but unfavorable for teat count.

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Emergency department (ED) triage is used to identify patients' level of urgency and treat them based on their triage level. The global advancement of triage scales in the past two decades has generated considerable research on the validity and reliability of these scales. This systematic review aims to investigate the scientific evidence for published ED triage scales. The following questions are addressed: 1. Does assessment of individual vital signs or chief complaints affect mortality during the hospital stay or within 30 days after arrival at the ED? 2. What is the level of agreement between clinicians' triage decisions compared to each other or to a gold standard for each scale (reliability)? 3. How valid is each triage scale in predicting hospitalization and hospital mortality? A systematic search of the international literature published from 1966 through March 31, 2009 explored the British Nursing Index, Business Source Premier, CINAHL, Cochrane Library, EMBASE, and PubMed. Inclusion was limited to controlled studies of adult patients (≥15 years) visiting EDs for somatic reasons. Outcome variables were death in ED or hospital and need for hospitalization (validity). Methodological quality and clinical relevance of each study were rated as high, medium, or low. The results from the studies that met the inclusion criteria and quality standards were synthesized applying the internationally developed GRADE system. Each conclusion was then assessed as having strong, moderately strong, limited, or insufficient scientific evidence. If studies were not available, this was also noted. We found ED triage scales to be supported, at best, by limited and often insufficient evidence. The ability of the individual vital signs included in the different scales to predict outcome is seldom, if at all, studied in the ED setting. The scientific evidence to assess interrater agreement (reliability) was limited for one triage scale and insufficient or lacking for all other scales. Two of the scales yielded limited scientific evidence, and one scale yielded insufficient evidence, on which to assess the risk of early death or hospitalization in patients assigned to the two lowest triage levels on a 5-level scale (validity).

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Bakgrund: Unga vuxna som sökte vård sökte oftast inte för den psykiska ohälsan utan istället för något somatiskt. Det är viktigt att få de yngre vuxna att söka sig till vården när behov uppstår och underlätta till en god förbindelse mellan sjukvården och de unga vuxna. Syfte: Syftet med denna studie var att beskriva unga vuxnas upplevelser av sjuksköterskans bemötande av psykisk ohälsa vid kontakt med hälso- och sjukvården. Metod: Studien genomfördes som en litteraturöversikt. Resultat: För de unga vuxna var det inte lätt att komma in i vården på rätt vårdnivå om personen inte kom i kontakt med en sjuksköterska som hade ett holistiskt synsätt. Vården för de unga med psykisk ohälsa bör vara tillgänglig och informationen om tillgängligheten behöver ständigt upprepas. Slutsats: Det är viktigt att sjuksköterskor har kunskap och erfarenhet av unga psykiska människor för att kunna hjälpa dem med den psykiska ohälsan när de söker vård. Relationen mellan patienten och sjuksköterskan är av stor vikt för den fortsatta kontakten med vården för den unge vuxna. Det är viktigt att de känner tillit och förtroende.

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Bakgrund: På somatiska vårdavdelningar är fallrisken hög då det gäller patienter med demenssjukdom. Olika faktorer leder till att denna patientgrupp riskerar att inneha hög fallfrekvens på sjukhus. Syftet är att beskriva hur sjuksköterskan med hjälp av omvårdnadsåtgärder kan förebygga fall hos patienter med demenssjukdom på somatiska vårdavdelningar. Metod som valts är en litteratur översikt som är baserad på 15 vetenskapliga artiklar av både kvalitativ- och kvantitativansats. Resultat: Att identifiera vilka faktorer som leder till ökad fallrisk är ett viktigt arbete för sjuksköterskan för att kunna sätta in rätt omvårdnadsåtgärder. Upprättandet av individanpassat fallpreventionsprogram kan förebygga fall genom att patientens styrkor och svagheter identifieras. Vårdmiljön har en stor betydelse för patienter med demenssjukdom för att motverka risken för fallolyckor. Genom att samverka med andra professioner kan sjuksköterskan få ett större urval av omvårdnadsåtgärder i det fallförebyggande arbetet. Olika sorters hjälpmedel kan användas i omvårdnaden och därmed förebygga fall och framförallt fallskador. Slutsats: Fallolyckor innebär svåra skador hos äldre patienter med demens med en lång vårdtid och ökat lidande som följd. Det bör därför ligga i sjuksköterskans intresse att mer systematiskt använda sig av någon av tidigare nämnda omvårdnadsåtgärder då de hjälper till att förhindra fallolyckor i hög grad.

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Bakgrund: Sjuksköterskor har i sitt dagliga arbete till uppgift att ge och ta emot rapport om patienterna hen vårdar. En god kommunikation krävs för att säkerställa att relevant information förmedlas och inte patientsäkerheten hotas. Syfte: Att beskriva strategier för hur kommunikationen kan förbättras vid överrapportering mellan sjuksköterskor inom den somatiska slutenvården. Metod: Litteraturöversikten är baserad på 15 vetenskapliga artiklar med kvalitativ, kvantitativ och mixad ansats. Artiklarna identifierades via sökningar i databaserna Cinahl, PubMed och Web of Science. Resultat: Tre strategier framkom: personlig överrapportering, användandet av standardiserade formulär och överrapportering vid patientens säng. Strategierna gav en effektivare, säkrare och mer tidssparande överrapportering. Slutsats: En god kommunikation mellan sjuksköterskorna är oerhört viktigt för att bibehålla en trygg och säker vård för patienterna. För att få en förbättrad kommunikation mellan sjuksköterskor vid överrapportering kan olika strategier användas. Då sjuksköterskorna ofta har en hög arbetsbelastning så krävs det att överrapporteringarna är strukturerade för att inte tappa bort viktig information.

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Bakgrund: Många patienter har behov av palliativ vård innan de avlider. I Sverige finns idag flera olika alternativ för specialiserad palliativ vård. Dessa räcker dock inte till för att vårda alla palliativa patienter vilket leder till att sjuksköterskor som arbetar på somatiska vårdavdelningar på sjukhus ofta möter dessa patienter. Syfte: Att beskriva sjuksköterskors upplevelser av att ge palliativ vård till patienter som vårdas på somatiska vårdavdelningar. Metod: Studien genomfördes som en litteraturöversikt där 15 artiklar ingick i resultatet. Datainsamling har gjorts i databaserna Cinahl, PubMed och Web of Science. Resultat: Sjuksköterskor upplevde att kommunikationen vid vård av palliativa patienter var svår på flera sätt. Rädsla att bemöta existentiella frågor, tidsbrist och en dysfunktionell kommunikation mellan vårdpersonal upplevdes som svårigheter för sjuksköterskorna. Detta ledde till att sjuksköterskor upplevde ett stort behov av utbildning och kompetensutveckling. Slutsats: Ett stort utbildningsbehov finns hos sjuksköterskor då de upplever många svårigheter i att vårda palliativt. För att kunna utveckla denna vårdform på somatiska avdelningar behövs mer utbildning och forskning inom området.

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BACKGROUND: Shared decision-making (SDM) is an emergent research topic in the field of mental health care and is considered to be a central component of a recovery-oriented system. Despite the evidence suggesting the benefits of this change in the power relationship between users and practitioners, the method has not been widely implemented in clinical practice. OBJECTIVE: The objective of this study was to investigate decisional and information needs among users with mental illness as a prerequisite for the development of a decision support tool aimed at supporting SDM in community-based mental health services in Sweden. METHODS: Three semi-structured focus group interviews were conducted with 22 adult users with mental illness. The transcribed interviews were analyzed using a directed content analysis. This method was used to develop an in-depth understanding of the decisional process as well as to validate and conceptually extend Elwyn et al.'s model of SDM. RESULTS: The model Elwyn et al. have created for SDM in somatic care fits well for mental health services, both in terms of process and content. However, the results also suggest an extension of the model because decisions related to mental illness are often complex and involve a number of life domains. Issues related to social context and individual recovery point to the need for a preparation phase focused on establishing cooperation and mutual understanding as well as a clear follow-up phase that allows for feedback and adjustments to the decision-making process. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: The current study contributes to a deeper understanding of decisional and information needs among users of community-based mental health services that may reduce barriers to participation in decision-making. The results also shed light on attitudinal, relationship-based, and cognitive factors that are important to consider in adapting SDM in the mental health system.

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Bakgrund: Patientens rätt att vara delaktig i planering och genomförande av sin vård betonas idag, men många patienter är mindre delaktiga än de önskar vara. Det finns många fördelar med att patienten är delaktig. Syfte: Att beskriva vilka faktorer som påverkar patientens delaktighet i omvårdnad från patientens och sjuksköterskans perspektiv inom somatisk slutenvård. Metod: Litteraturstudie baserad på 16 vetenskapliga artiklar, publicerade mellan åren 2006 och 2015. Sökning skedde i databaserna PubMed och CINAHL, samt i de funna artiklarnas referenslistor. Resultat: Fem kategorier med faktorer som påverkade patientens delaktighet i omvårdnad identifierades; kunskap, relationen mellan patienten och sjuksköterskan, sjuksköterskans förhållningssätt, patientens situation och egenskaper samt organisationen. Slutsats: Faktorerna inom de fem kategorierna utgör ett komplicerat samspel och varje patient är en unik person med egna önskemål och preferenser för delaktighet.