13 research outputs found

    Somatic embryogenesis as a regeneration method for clonal propagation of Mediterranean forest species

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    La mejora y conservación de recursos genéticos en especies forestales lleva siglos de retraso con respecto a las especies agrícolas. Los recursos forestales se han considerado tradicionalmente como recursos �mineros�, en los que primaba la mera extracción dejando exclusivamente a la regeneración natural la labor de sostenibilidad en los montes y dehesas o montados. Hoy en día, el necesario desarrollo del medio rural obliga a la explotación racional de los recursos como medio de garantizar su sostenibilidad. Por ello se está empezando a extender el criterio de que las especies forestales se pueden y deben �cultivar� en determinados espacios. Las características biológicas de las especies forestales las hacen, a menudo, recalcitrantes a las técnicas de mejora y conservación de recursos genéticos tradicionalmente aplicadas a especies agrícolas. En particular, la propagación vegetativa se ha utilizado ampliamente en muchos cultivos leñosos como una herramienta muy poderosa para capturar todo el potencial genético de combinaciones genéticas valiosas. En especies forestales, en particular en las mediterráneas, esta posibilidad raramente se ha podido aplicar debido a la baja capacidad morfogénica de estas especies y la fuerte influencia de la maduración o cambio de fase. En los últimos años la biotecnología forestal ha tenido un desarrollo espectacular. En particular las técnicas de regeneración clonal de plantas basadas en técnicas de cultivo in vitro, fundamentalmente vía embriogénesis somática, se están ya aplicando por muchas empresas privadas e instituciones públicas a nivel semi-operativo con diversas especies, para la conservación de material selecto y el establecimiento de ensayos clonales. Nuestros grupos de trabajo están desarrollando protocolos de regeneración por embriogénesis somática en distintas especies forestales. En esta comunicación se presenta el estado actual de los conocimientos en dos especies típicamente mediterráneas, el alcornoque (Quercus suber L.) y el pino piñonero (Pinus pinea L.), destacando los principales cuellos de botella para su aplicación a gran escala

    Crohn’s disease in a southern european country: Montreal classification and clinical activity

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    BACKGROUND: Given the heterogeneous nature of Crohn's disease (CD), our aim was to apply the Montreal Classification to a large cohort of Portuguese patients with CD in order to identify potential predictive regarding the need for medical and/or surgical treatment. METHODS: A cross-sectional study was used based on data from an on-line registry of patients with CD. RESULTS: Of the 1692 patients with 5 or more years of disease, 747 (44%) were male and 945 (56%) female. On multivariate analysis the A2 group was an independent risk factor of the need for steroids (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1-2.3) and the A1 and A2 groups for immunosuppressants (OR 2.2; CI 1.2-3.8; OR 1.4; CI 1.0-2.0, respectively). An L3+L3(4) and L(4) location were risk factors for immunosuppression (OR 1.9; CI 1.5-2.4), whereas an L1 location was significantly associated with the need for abdominal surgery (P < 0.001). After 20 years of disease, less than 10% of patients persisted without steroids, immunosuppression, or surgery. The Montreal Classification allowed us to identify different groups of disease severity: A1 were more immunosuppressed without surgery, most of A2 patients were submitted to surgery, and 52% of L1+L1(4) patients were operated without immunosuppressants. CONCLUSIONS: Stratifying patients according to the Montreal Classification may prove useful in identifying different phenotypes with different therapies and severity. Most of our patients have severe disease

    Crohn's disease in a southern European country: Montreal classification and clinical activity

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    BACKGROUND: Given the heterogeneous nature of Crohn's disease (CD), our aim was to apply the Montreal Classification to a large cohort of Portuguese patients with CD in order to identify potential predictive regarding the need for medical and/or surgical treatment. METHODS: A cross-sectional study was used based on data from an on-line registry of patients with CD. RESULTS: Of the 1692 patients with 5 or more years of disease, 747 (44%) were male and 945 (56%) female. On multivariate analysis the A2 group was an independent risk factor of the need for steroids (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1-2.3) and the A1 and A2 groups for immunosuppressants (OR 2.2; CI 1.2-3.8; OR 1.4; CI 1.0-2.0, respectively). An L3+L3(4) and L(4) location were risk factors for immunosuppression (OR 1.9; CI 1.5-2.4), whereas an L1 location was significantly associated with the need for abdominal surgery (P < 0.001). After 20 years of disease, less than 10% of patients persisted without steroids, immunosuppression, or surgery. The Montreal Classification allowed us to identify different groups of disease severity: A1 were more immunosuppressed without surgery, most of A2 patients were submitted to surgery, and 52% of L1+L1(4) patients were operated without immunosuppressants. CONCLUSIONS: Stratifying patients according to the Montreal Classification may prove useful in identifying different phenotypes with different therapies and severity. Most of our patients have severe disease

    One year of Lamivudine therapy for portuguese patients with chronic hepatitis B.

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    OBJECTIVE: To further verify the efficacy and safety of locally manufactured lamivudine on patients with chronic hepatitis B (CHB). METHODS: 2200 patients with CHB were recruited and received lamivudine orally 100 mg once daily for 12 months. The efficacy assessments included virologic response rate (defined by the absence of serum HBV DNA, HBeAg loss and HBeAg/HBeAb seroconversion), percentage of patients with normalization of alanine aminotransferase (ALT). Meanwhile improvement of quality of life (QOL) measured by mos SF-36 QOL questionnaire and liver histology evaluation were conducted in some patients. The safety assessments included adverse events, serious adverse events and laboratory abnormalities. All 2200 patients received at least one dose of medication and were all included in the safety population. RESULTS: Ninety seven percent of patients (2137/2200) recruited were HBV DNA positive by dot blot (sensitivity GRT or equal to 1.0 pg/ml) at baseline. At the end of 12 months treatment, HBV DNA was undetectable in 80% patients (1538/1920) with HBV DNA positive before treatment. Among the 79%(1744/2200) of the patients recruited had positive HBV DNA accompanied abnormal ALT levels at baseline, 72% patients became ALT normal. And among the 84% (1843/2200) of the patients recruited were HBV DNA and HBeAg positive, anti-HBe negative, 16% (269/1650) patients achieved HBeAg/HBeAb seroconversion after 12 months of lamivudine treatment. The HBeAg/HBeAb seroconversion rate was positive correlation to the ALT level before treatment. A total of 304 patients completed the health-related QOL questionnaire. After 12 months treatment, lamivudine improved both their physical and mental health, especially for their mental health. 133 evaluable, paired liver biopsies were obtained for histological assessment, among whom 115 patients had abnormal ALT levels at baseline. Compared with pre-treatment most of their liver injury got alleviated (51.9%) or no further deterioration (36%), only 12% worsening. During the 12 months treatment, 9% patients withdrew from the study and 17% patients showed at least one adverse event, mild or moderate. There were no obvious difference between this study and the previously reported lamivudine Phase II or III study with regard to the kinds, incidence and severity of adverse events. CONCLUSION: The efficacy and safety profile of the locally manufactured lamivudine 100 mg tablets are similar with those of the previously reported available lamivudine tablets imported in treating Chinese chronic hepatitis B patients

    Clinical Challenges in Crohn’s Disease

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    A doença de Crohn é uma doença inflamatória crónica do trato gastrointestinal. O aumento da incidência e a heterogeneidade desta patologia, com diferentes apresentações e prognóstico leva a uma constante preocupação em desenvolver e melhorar a sua classificação e tratamentoObjectivos: Elaborar recomendações (com base no nível de evidência e grau de recomendação) para 5 questões consideradas como os desafios clínicos na abordagem terapêutica da doença de Crohn na actualidade. Métodos: A metodologia adoptada pelo grupo de trabalho DC2 (Desafios Clínicos na Doença de Crohn) baseou‑se na seleção de 5 questões‑problema, por votação; elaboração, por cada subgrupo, de recomendações e reflexões nacionais para cada questão‑problema; discussão e aprovação das respostas e reflexões de cada questão, em reunião de consenso. Conclusões: Foi possível efectuar conclusões alicerçadas na evidência para as questões colocadas, recomendando‑se: 1) são factores preditivos de mau prognóstico o aparecimento da doença de Crohn antes dos 40 anos, doença estenosante e doença anal; 2) poder‑se‑á ponderar suspender os biológicos em doentes com remissão endoscópica e com biomarcadores normais; 3) os doentes com marcadores bioquímicos de atividade (nomeadamente a PCR e a calprotectina) têm maior probabilidade de recidiva; 4) perante uma falência aos biológicos é essencial assegurar que o tratamento com o primeiro fármaco foi optimizado. No caso do infliximab, está demonstrado que quer a redução do intervalo das administrações ou o aumento da dose permitem recuperar a resposta na larga maioria dos doentes. Em relação ao adalimumab, os doentes deverão passar de terapêutica quinzenal para semanal 5) em situação de doença de Crohn com cirurgia intestinal, o recurso a terapêutica de redução da recorrência pós‑cirurgia, particularmente imunossupressores e biológicos está indicado.info:eu-repo/semantics/publishedVersio

    WHO global research priorities for antimicrobial resistance in human health

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    The WHO research agenda for antimicrobial resistance (AMR) in human health has identified 40 research priorities to be addressed by the year 2030. These priorities focus on bacterial and fungal pathogens of crucial importance in addressing AMR, including drug-resistant pathogens causing tuberculosis. These research priorities encompass the entire people-centred journey, covering prevention, diagnosis, and treatment of antimicrobial-resistant infections, in addition to addressing the overarching knowledge gaps in AMR epidemiology, burden and drivers, policies and regulations, and awareness and education. The research priorities were identified through a multistage process, starting with a comprehensive scoping review of knowledge gaps, with expert inputs gathered through a survey and open call. The priority setting involved a rigorous modified Child Health and Nutrition Research Initiative approach, ensuring global representation and applicability of the findings. The ultimate goal of this research agenda is to encourage research and investment in the generation of evidence to better understand AMR dynamics and facilitate policy translation for reducing the burden and consequences of AMR

    WHO global research priorities for antimicrobial resistance in human health

    Get PDF
    The WHO research agenda for antimicrobial resistance (AMR) in human health has identified 40 research priorities to be addressed by the year 2030. These priorities focus on bacterial and fungal pathogens of crucial importance in addressing AMR, including drug-resistant pathogens causing tuberculosis. These research priorities encompass the entire people-centred journey, covering prevention, diagnosis, and treatment of antimicrobial-resistant infections, in addition to addressing the overarching knowledge gaps in AMR epidemiology, burden and drivers, policies and regulations, and awareness and education. The research priorities were identified through a multistage process, starting with a comprehensive scoping review of knowledge gaps, with expert inputs gathered through a survey and open call. The priority setting involved a rigorous modified Child Health and Nutrition Research Initiative approach, ensuring global representation and applicability of the findings. The ultimate goal of this research agenda is to encourage research and investment in the generation of evidence to better understand AMR dynamics and facilitate policy translation for reducing the burden and consequences of AMR

    Adventitious root formation in olive (Olea europaea L.) microshoots: anatomical evaluation and associated biochemical changes in peroxidase and polyphenol oxidase activities

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    Trials were performed using in vitro-cultured microshoots of the olive (Olea europaea L.) cultivar ‘Galega vulgar’, as initial explants, to identify histological events and modifications in peroxidase and polyphenol oxidase activities during adventitious root formation. Explant bases were submitted to a 10 s quick-dip treatment to promote rooting, using a sterile solution of 14.7 mM indole-3-butyric acid (IBA). Samples for histology and quantification of enzyme activities were collected at pre-established periods from 0 to 720 h.The first signs of modifications in stem cell morphology were observed 96 h after explant inoculation on olive culture medium (OM), with some cortical cells showing a dense cytoplasm and a large central nucleus, with visible nucleoli. The first mitotic events were observed after 144 h and evolved via two different pathways: non-specific cell division, leading to callus formation; and organised cell division, leading to the formation of root meristemoids. After 456 h, the first organised root primordia became visible. No root formation was achieved without earlier callus development, and 89% of root primordia originated from tissues other than cambial/phloem tissue. Peroxidase and polyphenol oxidase activities were recorded throughout the whole rooting process. The first significant modification in enzyme activity, with a drop from 0.19 to 0.14 ΔA490 units min-1 50 mg-1 of explant material, was observed for peroxidase within the first 4 h after IBA treatment. Subsequent changes in both enzyme activities could be correlated with different phases of the adventitious rooting process

    Adventitious root formation in olive (Olea europaea L.) microshoots; anatomical evaluation and associated biochemical changes in peroxidases and polyphenol oxidases activity.

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    Com o objetivo de identificar tanto fenómenos histológicos como alterações na atividade das peroxidases e polifenoloxidases durante a formação de raízes adventícias, em oliveira realizaram-se ensaios utilizando microestacas da cultivar ‘Galega vulgar’ previamente instalada em cultura in vitro. As bases dos explantes foram submetidas a um tratamento indutor do enraizamento, por imersão rápida (10 segundos) numa solução estéril de ácido indol-3-butírico a 14,7 mM. Em intervalos de tempos pré-estabelecidos foram recolhidas amostras tanto para os estudos histológicos como para os de quantificação da atividade enzimática. Os primeiros sinais de alteração na atividade celular foram identificados quatro dias após a inoculação dos explantes no meio de cultura, tendo-se observado na zona do córtex a existência de células com citoplasma denso, núcleos grandes e centrais e com nucléolos visíveis. As primeiras mitoses foram observadas após o sexto dia e evoluíram segundo duas vias bem diferenciadas; divisão celular não específica conduzindo à formação do calo cicatricial e divisão celular organizada levando à formação dos meristemóides radicais. Estes clusters organizados de células foram observados pela primeira vez aos dez dias após a inoculação dos explantes em cultura e evoluíram para a formação dos campos morfogénicos da raiz, estruturas que foram observadas após 14 dias. Após dezanove dias tornam-se visíveis os primeiros primórdios radiculares organizados, com uma polarização bem definida e clara vascularização. Sem o desenvolvimento prévio do calo cicatricial não se observou a formação de raízes. Oitenta e nove porcento das raízes formadas tiveram a sua origem fora da região câmbio/floema. Durante todo o processo de enraizamento foi registada a atividade das peroxidases e polifenoloxidases com as primeiras variações a ocorrerem imediatamente após o tratamento hormonal e com a sua evolução subsequente a poder ser correlacionada com as diferentes fases do processo de enraizamento adventíci
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