222 research outputs found

    Fertilizante de liberação lenta no desenvolvimento de mudas de Eucalyptus grandis.

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    Uma das ações mais importantes para aumentar a produção de mudas de essências florestais é a fertilização do substrato. A utilização de fertilizante de liberação lenta (FLL) pode contribuir para a obtenção de mudas de melhor qualidade. O objetivo do trabalho foi avaliar doses crescentes de FLL e fertilizante convencional (FC), bem como comparar esses fertilizantes no desenvolvimento de mudas de Eucalyptus grandis. O estudo foi realizado na região do Vale do Itajaí, SC. Os tratamentos foram a adição de FLL e FC para cada experimento nas seguintes doses de formulado: T1 ? 0 kg (testemunha); T2 ? 2 kg; T3 ? 4 kg; T4 ? 6 kg; T5 ? 8 kg e T6 ? 10 kg.m-3 de substrato-base. Decorridos 174 dias da semeadura, foram analisadas as variáveis altura total, diâmetro do colo, biomassa fresca da parte aérea, biomassa seca da parte aérea, biomassa seca da raiz, biomassa seca total, dose de máxima eficiência técnica e teores de nutrientes da parte aérea das mudas de cada tratamento. Em todos os tratamentos houve resposta positiva no desenvolvimento das mudas, entretanto as mudas tiveram melhor crescimento sob doses entre 9,1 e 12,9 kg.m-3 de fertilizante de liberação lenta

    Caracterização de sementes de cornichão (Lotus corniculatus L.) e desenvolvimento de suspensões para recobrimento.

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    Objetivo desse trabalho foi caracterizar física e fisiologicamente as sementes de cornichão a fim de conhecer suas propriedades e elaborar filmes para seu recobrimento que apresentem potencial protetor, melhorem as características físicas e que apresentem as características necessárias para atomização em futuros trabalhos de recobrimento em leito de jorro.ENEMP

    Recobrimento de sementes de cornichão (Lotus Corniculatus L.) utilizando polímeros comerciais.

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    Atualmente a alimentação bovina é baseada em pastagens com um potencial forrageiro elevado.Número especial. Trabalho 520. Edição dos Resumos do 19º Congresso Brasileiro de Sementes, Foz do Iguaçu, set. 2015

    Krt19\u3csup\u3e+\u3c/sup\u3e/Lgr5\u3csup\u3e-\u3c/sup\u3e Cells Are Radioresistant Cancer-Initiating Stem Cells in the Colon and Intestine

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    Epithelium of the colon and intestine are renewed every 3 days. In the intestine there are at least two principal stem cell pools. The first contains rapid cycling crypt-based columnar (CBC) Lgr5+ cells, and the second is composed of slower cycling Bmi1-expressing cells at the +4 position above the crypt base. In the colon, however, the identification of Lgr5- stem cell pools has proven more challenging. Here, we demonstrate that the intermediate filament keratin-19 (Krt19) marks long-lived, radiation-resistant cells above the crypt base that generate Lgr5+ CBCs in the colon and intestine. In colorectal cancer models, Krt19+ cancer-initiating cells are also radioresistant, while Lgr5+ stem cells are radiosensitive. Moreover, Lgr5+ stem cells are dispensable in both the normal and neoplastic colonic epithelium, as ablation of Lgr5+ stem cells results in their regeneration from Krt19-expressing cells. Thus, Krt19+ stem cells are a discrete target relevant for cancer therapy

    Alterations in regulatory T cells and immune checkpoint molecules in pancreatic cancer patients receiving FOLFIRINOX or gemcitabine plus nab-paclitaxel

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    PURPOSE This pilot study aimed on generating insight on alterations in circulating immune cells during the use of FOLFIRINOX and gemcitabine/nab-paclitaxel in pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS Peripheral blood mononuclear cells were isolated before and 30~days after initiation of chemotherapy from 20 patients with advanced PDAC. Regulatory T cells (FoxP3+) and immune checkpoints (PD-1 and TIM-3) were analyzed by flow cytometry and immunological changes were correlated with clinical outcome. RESULTS Heterogeneous changes during chemotherapy were observed in circulating T-cell subpopulations with a pronounced effect on PD-1+ CD4+/CD8+ T cells. An increase in FoxP3+ or PD-1+ T cells had no significant effect on survival. An increase in TIM3+/CD8+ (but not TIM3+/CD4+) T cells was associated with a significant inferior outcome: median progression-free survival in the subgroup with an increase of TIM-3+/CD8+ T cells was 6.0 compared to 14.0~months in patients with a decrease/no change (p = 0.026); corresponding median overall survival was 13.0 and 20.0~months (p = 0.011), respectively. CONCLUSIONS Chemotherapy with FOLFIRNOX or gemcitabine/nab-paclitaxel induces variable changes in circulating T-cell populations that may provide prognostic information in PDAC

    CCK2R identifies and regulates gastric antral stem cell states and carcinogenesis

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    Objective Progastrin is the incompletely cleaved precursor of gastrin that is secreted by G-cells in the gastric antrum. Both gastrin and progastrin bind to the CCK2 receptor (Cckbr or CCK2R) expressed on a subset of gastric epithelial cells. Little is known about how gastrin peptides and CCK2R regulate gastric stem cells and carcinogenesis. Interconversion among progenitors in the intestine is documented, but the mechanisms by which this occurs are poorly defined. Design We generated CCK2R-CreERT mice and performed inducible lineage tracing experiments. CCK2R+ antral cells and Lgr5+ antral stem cells were cultured in a three-dimensional in vitro system. We crossed progastrin-overexpressing mice with Lgr5-GFP-CreERT mice and examined the role of progastrin and CCK2R in Lgr5+ stem cells during MNU-induced carcinogenesis. Results Through lineage tracing experiments, we found that CCK2R defines antral stem cells at position +4, which overlapped with an Lgr5neg or low cell population but was distinct from typical antral Lgr5high stem cells. Treatment with progastrin interconverts Lgr5neg or low CCK2R+ cells into Lgr5high cells, increases CCK2R+ cell numbers and promotes gland fission and carcinogenesis in response to the chemical carcinogen MNU. Pharmacological inhibition or genetic ablation of CCK2R attenuated progastrin-dependent stem cell expansion and carcinogenesis. Conclusions CCK2R labels +4 antral stem cells that can be activated and expanded by progastrin, thus identifying one hormonal trigger for gastric stem cell interconversion and a potential target for gastric cancer chemoprevention and therapy

    The impact of COVID-19 on oncology professionals – one year on:lessons learned from the ESMO Resilience Task Force survey series

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    Highlights • Risk of distress/burnout amongst oncology professionals continues to worsen since COVID-19 despite improved job performance. • Female and younger (≤40 years old) colleagues continue to be at higher risk of poor well-being and feeling burnout. • Job demands have increased, with nearly half now feeling overwhelmed with workload. • Concerns regarding career development/training, job security, and international fellowship opportunities remain high. • A quarter of oncology professionals reported considering changing their career, including leaving the oncology profession. Background COVID-19 has had a significant impact on the well-being and job performance of oncology professionals globally. The European Society for Medical Oncology (ESMO) Resilience Task Force collaboration set out to investigate and monitor well-being since COVID-19 in relation to work, lifestyle and support factors in oncology professionals 1 year on since the start of the pandemic. Methods An online, anonymous survey was conducted in February/March 2021 (Survey III). Key outcome variables included risk of poor well-being or distress (expanded Well-Being Index), feeling burnout (single item from expanded Well-Being Index), and job performance since COVID-19. Longitudinal analysis of responses to the series of three surveys since COVID-19 was carried out, and responses to job demands and resources questions were interrogated. SPSS V.26.0/V.27.0 and GraphPad Prism V9.0 were used for statistical analyses. Results Responses from 1269 participants from 104 countries were analysed in Survey III: 55% (n = 699/1269) female, 54% (n = 686/1269) >40 years, and 69% (n = 852/1230) of white ethnicity. There continues to be an increased risk of poor well-being or distress (n = 464/1169, 40%) and feeling burnout (n = 660/1169, 57%) compared with Survey I (25% and 38% respectively, P < 0.0001), despite improved job performance. Compared with the initial period of the pandemic, more participants report feeling overwhelmed with workload (45% versus 29%, P < 0.0001). There remain concerns about the negative impact of the pandemic on career development/training (43%), job security (37%). and international fellowship opportunities (76%). Alarmingly, 25% (n = 266/1086) are considering changing their future career with 38% (n = 100/266) contemplating leaving the profession. Conclusion Oncology professionals continue to face increased job demands. There is now significant concern regarding potential attrition in the oncology workforce. National and international stakeholders must act immediately and work closely with oncology professionals to draw up future-proof recovery plans

    Denervation suppresses gastric tumorigenesis

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    The nervous system plays an important role in the regulation of epithelial homeostasis and has also been postulated to play a role in tumorigenesis. We provide evidence that proper innervation is critical at all stages of gastric tumorigenesis. In three separate mouse models of gastric cancer, surgical or pharmacological denervation of the stomach (bilateral or unilateral truncal vagotomy, or local injection of botulinum toxin type A) markedly reduced tumor incidence and progression, but only in the denervated portion of the stomach. Vagotomy or botulinum toxin type A treatment also enhanced the therapeutic effects of systemic chemotherapy and prolonged survival. Denervation-induced suppression of tumorigenesis was associated with inhibition of Wnt signaling and suppression of stem cell expansion. In gastric organoid cultures, neurons stimulated growth in a Wnt-mediated fashion through cholinergic signaling. Furthermore, pharmacological inhibition or genetic knockout of the muscarinic acetylcholine M[subscript 3] receptor suppressed gastric tumorigenesis. In gastric cancer patients, tumor stage correlated with neural density and activated Wnt signaling, whereas vagotomy reduced the risk of gastric cancer. Together, our findings suggest that vagal innervation contributes to gastric tumorigenesis via M[subscript 3] receptor–mediated Wnt signaling in the stem cells, and that denervation might represent a feasible strategy for the control of gastric cancer

    The observational clinical registry (cohort design) of the European Reference Network on Rare Adult Solid Cancers: The protocol for the rare head and neck cancers

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    Care for head and neck cancers is complex in particular for the rare ones. Knowledge is limited and histological heterogeneity adds complexity to the rarity. There is a wide consensus that to support clinical research on rare cancer, clinical registries should be developed within networks specializing in rare cancers. In the EU, a unique opportunity is provided by the European Reference Networks (ERN). The ERN EURACAN is dedicated to rare adults solid cancers, here we present the protocol of the EURACAN registry on rare head and neck cancers (ClinicalTrials.gov Identifier: NCT05483374). Study design Registry-based cohort study including only people with rare head and neck cancers. Objectives 1.To help describe the natural history of rare head and neck cancers; 2.To evaluate factors that influence prognosis; 3.To assess treatment effectiveness; 4.To measure indicators of quality of care. Methods Settings and participants It is an hospital based registry established in hospitals with expertise in head and neck cancers. Only adult patients with epithelial tumours of nasopharynx; nasal cavity and paranasal sinuses; salivary gland cancer in large and small salivary glands; and middle ear will be included in the registry. This registry won t select a sample of patients. Each patient in the facility who meets the above mentioned inclusion criteria will be followed prospectively and longitudinally with follow-up at cancer progression and / or cancer relapse or patient death. It is a secondary use of data which will be collected from the clinical records. The data collected for the registry will not entail further examinations or admissions to the facility and/or additional appointments to those normally provided for the patient follow-up. Variables Data will be collected on patient characteristics (eg. patient demographics, lifestyle, medical history, health status); exposure data (eg. disease, procedures, treatments of interest) and outcomes (e.g. survival, progression, progression-free survival, etc.). In addition, data on potential confounders (e.g. comorbidity; functional status etc.) will be also collected. Statistical methods The data analyses will include descriptive statistics showing patterns of patients and cancers variables and indicators describing the quality of care. Multivariable Cox s proportional hazards model and Hazard ratios (HR) for all-cause or cause specific mortality will be used to determine independent predictors of overall survival, recurrence etc. Variables to include in the multivariable regression model will be selected based on the results of univariable analysis. The role of confounding or effect modifiers will be evaluated using stratified analysis or sensitivity analysis. To assess treatment effectiveness, multivariable models with propensity score adjustment and progression-free survival will be performed. Adequate statistical (eg. marginal structural model) methods will be used if time-varying treatments/ confounders and confounding by indication (selective prescribing) will be present. Results The registry initiated recruiting in May 2022. The estimated completion date is December 2030 upon agreement on the achievement of all the registry objectives. As of October 2022, the registry is recruiting. There will be a risk of limited representativeness due to the hospital-based nature of the registry and to the fact that hospital contributing to the registry are expert centres for these rare cancers. Clinical Follow-up could also be an issue but active search of the life status of the patients will be guaranteed
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