Avaliação e seleção de porta-enxertos de videira (Vitis spp.) tolerantes ao déficit hídrico através de aprendizagem de máquina.

Os programas de melhoramento genético de plantas buscam selecionar genótipos superiores, para atender as necessidades do homem, no aumento da produtividade, na stabilidade e qualidade das espécies de importância econômica, assim como na redução dos impactos ambientais e nos custos de produção. Dessa forma, a videira (Vitis spp.) é considerada uma fruteira perene de grande importância econômica, social e alimentar. Porém face às mudanças climáticas e a limitação de recursos hídricos, tem havido um crescente investimento no desenvolvimento e uso de porta enxertos tolerantes ao déficit hídrico. No entanto, a obtenção de novas cultivares, tolerantes ao déficit hídrico, trata-se de um processo demorado e difícil por ser uma característica poligênica. Por conta disto, o uso de novas ferramentas, tais como o uso algoritmos de aprendizado de máquina podem facilitar identificação e obtenção de novas cultivares tolerantes ao déficit hídrico, devido a capacidade de gerenciar grandes quantidades de dados e identificar padrões relevantes. Neste sentido, o objetivo deste trabalho foi de avaliar a divergência genética de 45 cultivares de porta enxertos de videira, assim como, de predizer classes de tolerância ao déficit hídrico nas três cultivares brasileiras IAC313, IAC572 e IAC766, cuja a informação na literatura é desconhecida, através de algoritmos de aprendizagem de máquina. Como método para análise de divergência genética, foram empregados algoritmos de agrupamento K-means e a Análise de Componentes Principais. A partir dos resultados obtidos na análise de divergência genética para as características avaliadas, foram formados cinco grupos heteróticos e identificados 37 opções de cruzamentos viáveis, indicando existir divergência entre as cultivares. Para a predição de classes de tolerância ao déficit hídrico, foi comparado o desempenho de seis algoritmos distintos, como o Decision Tree, Random Forest, K-Nearest Neighbors, XGBoost, Support Vector Machines e Linear Discriminant Analysis. E em seguida através do algoritmo com melhor desempenho, predizer o grau de tolerância ao déficit hídrico das três cultivares brasileiras. Os resultados indicaram o Random Forest como melhor algoritmo e pode-se predizer que as cultivares IAC 313 e IAC 766 apresentam alta tolerância ao déficit hídrico e o IAC 572 baixa tolerância. Neste sentido, o uso algoritmos de aprendizado de máquina em nosso trabalho, possibilitaram alcançar resultados de fácil entendimento, mostrando-se como mais uma opção de ferramenta acessível e útil ao melhorista, para a identificação de melhores cruzamentos para uma característica específica e predição de classes.Dissertação (Mestrado em Agronomia. Melhoramento Genético de Plantas.) - Universidade Federal Rural de Pernambuco, Recife. Orientada por Rosimar dos Santos Musser; co-orientadores: André Câmara Alves do Nascimento. Patrícia Coelho de Souza Leão, Embrapa Semiárido

Classificação de porta-enxertos de videira tolerantes à seca usando aprendizagem de máquinas.

O objetivo deste trabalho foi de descobrir o grau de tolerância à seca das cultivares IAC 313, IAC 572 e IAC 766 através do aprendizado de máquinas, com o intuito de indicar os materiais mais promissores em trabalhos de seleção de porta enxertos tolerantes ao déficit hídrico para o cultivo da videira na região do Submédio do Vale do São Francisco

Lessons learned about appendiceal neuroendocrine neoplasms from data analysis of the Belgian Cancer Registry 2010-2015.

Appendiceal neuroendocrine neo-plasms (aNENs) are a diverse group of malignant neoplasms of varying biological behavior for which information about manage-ment and outcome is sparse, with the majority of available studies being retrospective, including only a limited number of patients, and therefore not necessarily reflecting the reality in the community. In the present study clinical, epidemiological and pathological data of appendiceal neuroendocrine neoplasms in Belgium is provided and compared with current literature. A population-based study was conducted by linking data of the Belgian Cancer Registry with medical procedures in the Belgian Health Insurance database for patients diagnosed with aNEN between 2010 and 2015. We found an aNEN incidence of 0.97/100.000 person years in Belgium. Neuroendocrine carcinoma of the appendix are rare. Most appendiceal neuroendocrine tumors (aNETs) are small G1 tumors. Positive lymph nodes are often found in tumors larger than 2cm, especially aNET G2. A rapid uptake of changing classifications was seen in the community. However, systematic reporting of risk factors for small aNEN can still be improved and should be stimulated. In 9% of cases, reclassifications had to be made, pointing out that in a retrospective analysis, original pathological reports should be checked for specific parameters, before reliable conclusions can be drawn

Septuagenarian and octogenarian donors provide excellent liver grafts for transplantation.

Background: Wider utilization of liver grafts from donors <70 years old could substantially expand the organ pool, but their use remains limited by fear of poorer outcomes. We examined the results at our center of liver transplantation (OLT) using livers from donors <70 years old. Methods: From February 2003 to August 2010, we performed 450 OLT including 58 (13%) using donors <70 whose outcomes were compared with those using donors <70 years old. Results: Cerebrovascular causes of death predominated among donors <70 (85% vs 47% in donors <70; P <.001). In contrast, traumatic causes of death predominated among donors <70 (36% vs 14% in donors <70; P =.002). Unlike grafts from donors <70 years old, grafts from older individuals had no additional risk factors (steatosis, high sodium, or hemodynamic instability). Both groups were comparable for cold and warm ischemia times. No difference was noted in posttransplant peak transaminases, incidence of primary nonfunction, hepatic artery thrombosis, biliary strictures, or retransplantation rates between groups. The 1- and 5-year patient survivals were 88% and 82% in recipients of livers <70 versus 90% and 84% in those from <70 years old (P =.705). Recipients of older grafts, who were 6 years older than recipients of younger grafts (P <.001), tended to have a lower laboratory Model for End-Stage Liver Disease score (P =.074). Conclusions: Short and mid-term survival following OLT using donors <70 yo can be excellent provided that there is adequate donor and recipient selection. Septuagenarians and octogenarians with cerebrovascular ischemic and bleeding accidents represent a large pool of potential donors whose wider use could substantially reduce mortality on the OLT waiting list

Pembrolizumab in combination with gemcitabine and cisplatin compared with gemcitabine and cisplatin alone for patients with advanced biliary tract cancer (KEYNOTE-966) : a randomised, double-blind, placebo-controlled, phase 3 trial

Background: Biliary tract cancers, which arise from the intrahepatic or extrahepatic bile ducts and the gallbladder, generally have a poor prognosis and are rising in incidence worldwide. The standard-of-care treatment for advanced biliary tract cancer is chemotherapy with gemcitabine and cisplatin. Because most biliary tract cancers have an immune-suppressed microenvironment, immune checkpoint inhibitor monotherapy is associated with a low objective response rate. We aimed to assess whether adding the immune checkpoint inhibitor pembrolizumab to gemcitabine and cisplatin would improve outcomes compared with gemcitabine and cisplatin alone in patients with advanced biliary tract cancer. Methods: KEYNOTE-966 was a randomised, double-blind, placebo-controlled, phase 3 trial done at 175 medical centres globally. Eligible participants were aged 18 years or older; had previously untreated, unresectable, locally advanced or metastatic biliary tract cancer; had disease measurable per Response Evaluation Criteria in Solid Tumours version 1.1; and had an Eastern Cooperative Oncology Group performance status of 0 or 1. Eligible participants were randomly assigned (1:1) to pembrolizumab 200 mg or placebo, both administered intravenously every 3 weeks (maximum 35 cycles), in combination with gemcitabine (1000 mg/m2 intravenously on days 1 and 8 every 3 weeks; no maximum duration) and cisplatin (25 mg/m2 intravenously on days 1 and 8 every 3 weeks; maximum 8 cycles). Randomisation was done using a central interactive voice-response system and stratified by geographical region, disease stage, and site of origin in block sizes of four. The primary endpoint of overall survival was evaluated in the intention-to-treat population. The secondary endpoint of safety was evaluated in the as-treated population. This study is registered at ClinicalTrials.gov, NCT04003636. Findings: Between Oct 4, 2019, and June 8, 2021, 1564 patients were screened for eligibility, 1069 of whom were randomly assigned to pembrolizumab plus gemcitabine and cisplatin (pembrolizumab group; n=533) or placebo plus gemcitabine and cisplatin (placebo group; n=536). Median study follow-up at final analysis was 25·6 months (IQR 21·7–30·4). Median overall survival was 12·7 months (95% CI 11·5–13·6) in the pembrolizumab group versus 10·9 months (9·9–11·6) in the placebo group (hazard ratio 0·83 [95% CI 0·72–0·95]; one-sided p=0·0034 [significance threshold, p=0·0200]). In the as-treated population, the maximum adverse event grade was 3 to 4 in 420 (79%) of 529 participants in the pembrolizumab group and 400 (75%) of 534 in the placebo group; 369 (70%) participants in the pembrolizumab group and 367 (69%) in the placebo group had treatment-related adverse events with a maximum grade of 3 to 4. 31 (6%) participants in the pembrolizumab group and 49 (9%) in the placebo group died due to adverse events, including eight (2%) in the pembrolizumab group and three (1%) in the placebo group who died due to treatment-related adverse events. Interpretation: Based on a statistically significant, clinically meaningful improvement in overall survival compared with gemcitabine and cisplatin without any new safety signals, pembrolizumab plus gemcitabine and cisplatin could be a new treatment option for patients with previously untreated metastatic or unresectable biliary tract cancer