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1.
Eur J Surg Oncol ; 50(7): 108375, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795677

RESUMO

INTRODUCTION: Distal Cholangiocarcinoma (dCCA) represents a challenge in hepatobiliary oncology, that requires nuanced post-resection prognostic modeling. Conventional staging criteria may oversimplify dCCA complexities, prompting the exploration of novel prognostic factors and methodologies, including machine learning algorithms. This study aims to develop a machine learning predictive model for recurrence after resected dCCA. MATERIAL AND METHODS: This retrospective multicentric observational study included patients with dCCA from 13 international centers who underwent curative pancreaticoduodenectomy (PD). A LASSO-regularized Cox regression model was used to feature selection, examine the path of the coefficient and create a model to predict recurrence. Internal and external validation and model performance were assessed using the C-index score. Additionally, a web application was developed to enhance the clinical use of the algorithm. RESULTS: Among 654 patients, LNR (Lymph Node Ratio) 15, neural invasion, N stage, surgical radicality, and differentiation grade emerged as significant predictors of disease-free survival (DFS). The model showed the best discrimination capacity with a C-index value of 0.8 (CI 95 %, 0.77%-0.86 %) and highlighted LNR15 as the most influential factor. Internal and external validations showed the model's robustness and discriminative ability with an Area Under the Curve of 92.4 % (95 % CI, 88.2%-94.4 %) and 91.5 % (95 % CI, 88.4%-93.5 %), respectively. The predictive model is available at https://imim.shinyapps.io/LassoCholangioca/. CONCLUSIONS: This study pioneers the integration of machine learning into prognostic modeling for dCCA, yielding a robust predictive model for DFS following PD. The tool can provide information to both patients and healthcare providers, enhancing tailored treatments and follow-up.


Assuntos
Inteligência Artificial , Neoplasias dos Ductos Biliares , Colangiocarcinoma , Aprendizado de Máquina , Recidiva Local de Neoplasia , Pancreaticoduodenectomia , Humanos , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Idoso , Intervalo Livre de Doença , Estadiamento de Neoplasias , Prognóstico
2.
Polymers (Basel) ; 16(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611181

RESUMO

The present work proposes to investigate the effect of an ultrahigh molecular weight silicone rubber (UHMW-SR) and two ethylene methyl acrylate copolymers (EMA) with different methyl acrylate (MA) content on the mechanical and fire performance of a fireproof acrylonitrile butadiene styrene copolymer (ABS) composite, with an optimum amount of ammonium polyphosphate (APP) and aluminum diethyl phosphinate (AlPi). ABS formulations with a global flame retardant weight content of 20 wt.% (ABS P) were melt-compounded, with and without EMA and UHMW-SR, in a Brabender mixer. During this batch process, ABS P formulations with UHMW-SR and/or EMA registered lower torque values than those of ABS P. By means of scanning electron microscopy (SEM), it was possible to observe that all ABS composites exhibited a homogenous structure without phase separation or particle agglomeration. Slightly improved interfacial interaction between the well-dispersed flame-retardant particles in the presence of EMA and/or UHMW-SR was also noticed. Furthermore, synergies in mechanical properties by adding both EMA and UHMW-SR into ABS P were ascertained. An enhancement of molecular mobility that contributed to the softening of ABS P was observed under dynamic mechanical thermal analysis (DMTA). An improvement of its flexibility, ductility and toughness were also registered under three-point-bending trials, and even more remarkable synergies were noticed in Charpy notched impact strength. Particularly, a 212% increase was achieved when 5 wt.% of EMA with 29 wt.% of MA and 2 wt.% of UHMW-SR in ABS P (ABS E29 S P) were added. Thermogravimetric analysis (TGA) showed that the presence of EMA copolymers in ABS P formulations did not interfere with its thermal decomposition, whereas UHMW-SR presence decreased its thermal stability at the beginning of the decomposition. Although the addition of EMA or UHMW-SR, as well as the combination of both in ABS P increased the pHRR in cone calorimetry, UL 94 V-0 classification was maintained for all flame-retarded ABS composites. In addition, through SEM analysis of cone calorimetry sample residue, a more cohesive surface char layer, with Si-O-C network formation confirmed by Fourier transform infrared (FTIR), was shown in ABS P formulations with UHMW-SR.

3.
Polymers (Basel) ; 15(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36771927

RESUMO

This work reports on tailoring the magnetic properties of acrylonitrile butadiene styrene (ABS)-based composites for their application in magnetoactive systems, such as magnetic sensors and actuators. The magnetic properties of the composites are provided by the inclusion of varying permalloy (Py-Ni75Fe20Mo5) nanoparticle content within the ABS matrix. Composites with Py nanoparticle content up to 80 wt% were prepared and their morphological, mechanical, thermal, dielectric and magnetic properties were evaluated. It was found that ABS shows the capability to include high loads of the filler without negatively influencing its thermal and mechanical properties. In fact, the thermal properties of the ABS matrix are basically unaltered with the inclusion of the Py nanoparticles, with the glass transition temperatures of pristine ABS and its composites remaining around 105 °C. The mechanical properties of the composites depend on filler content, with the Young's modulus ranging from 1.16 GPa for the pristine ABS up to 1.98 GPa for the sample with 60 wt% filler content. Regarding the magnetic properties, the saturation magnetization of the composites increased linearly with increasing Py content up to a value of 50.9 emu/g for the samples with 80 wt% of Py content. A numerical model has been developed to support the findings about the magnetic behavior of the NP within the ABS. Overall, the slight improvement in the mechanical properties and the magnetic properties provides the ABS composites new possibilities for applications in magnetoactive systems, including magnetic sensors, actuators and magnetic field shielding.

4.
J Am Coll Surg ; 235(5): 703-712, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36102558

RESUMO

BACKGROUND: Several variables have been described as prognostic factors for resected distal cholangiocarcinoma (dCC), including lymph node metastases (N status) and lymph node ratio (LNR). The present study aimed to evaluate the prognostic value of LNR on survival and to establish a novel prognostic nomogram to predict the cancer-specific recurrence-free survival (RFS) of dCC. STUDY DESIGN: Between December 2006 and September 2020, 415 consecutive patients who underwent pancreaticoduodenectomy (PD) for dCC in 10 centers were identified. Multivariate Cox analysis was used to identify all independent risk factors among several prognostic factors. A nomogram was then developed and assessed by integrating the independent prognostic factors into the model, and the concordance index (C-index) was used to evaluate its performance. RESULTS: According to Cox regression multivariate analysis, a nomogram based on independent prognostic factor for RFS was performed including LNR 15 (hazard ratio [HR] 2.442, 95% CI 1.348-4.425, p = 0.003), perineural invasion (HR 3.100, 95% CI 1.183-8.122, p = 0.025), differentiation grade (HR 2.100, 95% CI 1.172-4.143, p = 0.021), and radicality of PD (HR 2.276, 95% CI 1.223-4.234, p = 0.009). The C-index of the nomogram, tailored based on the previous significant factors, was 0.8. CONCLUSIONS: LNR15 yields a high prognostic efficiency for RFS. The nomogram based on LNR can provide an accurate prognosis assessment for patients with resected dCC.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Humanos , Excisão de Linfonodo , Razão entre Linfonodos , Linfonodos/patologia , Linfonodos/cirurgia , Estadiamento de Neoplasias , Nomogramas , Prognóstico , Estudos Retrospectivos
6.
Ther Adv Musculoskelet Dis ; 13: 1759720X211009017, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33948127

RESUMO

BACKGROUND: Patients with fibromyalgia (FM) frequently resort to osteopathic or chiropractic treatment, despite very weak supporting evidence. We aimed to assess the efficacy of osteopathic manipulation in FM in a properly controlled and powered randomized clinical trial. METHODS: Patients were randomized to osteopathic or sham treatment. Treatment was administered by experienced physical medicine physicians, and consisted of six sessions per patient, over 6 weeks. Treatment credibility and expectancy were repeatedly evaluated. Patients completed standardized questionnaires at baseline, during treatment, and at 6, 12, 24, and 52 weeks after randomization. The primary outcome was pain intensity (100-mm visual analog scale) during the treatment period. Secondary outcomes included fatigue, functioning, and health-related quality of life. We performed primarily intention-to-treat analyses adjusted for credibility, using multiple imputation for missing data. RESULTS: In total, 101 patients (94% women) were included. Osteopathic treatment did not significantly decrease pain relative to sham treatment (mean difference during treatment: -2.2 mm; 95% confidence interval, -9.1 to 4.6 mm). No significant differences were observed for secondary outcomes. No serious adverse events were observed, despite a likely rebound in pain and altered functioning at week 12 in patients treated by osteopathy. Patient expectancy was predictive of pain during treatment, with a decrease of 12.9 mm (4.4-21.5 mm) per 10 points on the 0-30 scale. Treatment credibility and expectancy were also predictive of several secondary outcomes. CONCLUSION: Osteopathy conferred no benefit over sham treatment for pain, fatigue, functioning, and quality of life in patients with FM. These findings do not support the use of osteopathy to treat these patients. More attention should be paid to the expectancy of patients in FM management.

7.
Arch. argent. pediatr ; 119(1): 56-61, feb. 2021.
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-1147089

RESUMO

La leche materna provee microorganismos que colonizan el intestino y programan el sistema inmunológico para desarrollar tolerancia oral. Entre los 6 meses de lactancia materna exclusiva y los 2 años de lactancia prolongada recomendada, la alimentación complementaria conlleva una reducción progresiva en el ingreso de microorganismos vivos al ecosistema intestinal. Esto se debe a que los alimentos en general -a diferencia de la leche materna- o se encuentran desprovistos de microorganismos o, si los poseen, suelen inactivarse durante la cocción. Los alimentos fermentados y los probióticos podrían constituir una estrategia nutricional valiosa, dado que garantizarían la provisión de microorganismos vivos ante la reducción o interrupción anticipada de la lactancia. Los términos "alimentos fermentados" y "probióticos" no son sinónimos. La identidad microbiológica, la inocuidad y la existencia de estudios clínicos de eficacia para unos y otros son claves para entender sus diferencias y decidir una eventual recomendación alimentaria


Breast milk provides microorganisms that colonize the gut and program the immune system to develop oral tolerance. Between the 6 months of exclusive breastfeeding and the recommended 2 years of prolonged breastfeeding, complementary feeding leads to a progressive reduction in the entry of live microorganisms into the gut ecosystem. This is because foods in general -unlike breast milk- are devoid of microorganisms or, if present, they are often inactivated during cooking. Fermented foods and probiotics could be a valuable nutritional strategy, as they would ensure the supply of live microorganisms in the face of a reduction or early cessation of breastfeeding. The terms "fermented foods" and "probiotics" are not synonymous. Microbiological identity, safety, and the existence of clinical efficacy studies supporting both are key to understand their differences and decide on an eventual dietary recommendation


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Alimentos Fermentados , Iogurte , Probióticos , Microbiota , Imunidade , Fenômenos Fisiológicos da Nutrição do Lactente
8.
N Engl J Med ; 383(5): 426-439, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32726529

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is the dominant cause of severe lower respiratory tract infection in infants, with the most severe cases concentrated among younger infants. METHODS: Healthy pregnant women, at 28 weeks 0 days through 36 weeks 0 days of gestation, with an expected delivery date near the start of the RSV season, were randomly assigned in an overall ratio of approximately 2:1 to receive a single intramuscular dose of RSV fusion (F) protein nanoparticle vaccine or placebo. Infants were followed for 180 days to assess outcomes related to lower respiratory tract infection and for 364 days to assess safety. The primary end point was RSV-associated, medically significant lower respiratory tract infection up to 90 days of life, and the primary analysis of vaccine efficacy against the primary end point was performed in the per-protocol population of infants (prespecified criterion for success, lower bound of the 97.52% confidence interval [CI] of ≥30%). RESULTS: A total of 4636 women underwent randomization, and there were 4579 live births. During the first 90 days of life, the percentage of infants with RSV-associated, medically significant lower respiratory tract infection was 1.5% in the vaccine group and 2.4% in the placebo group (vaccine efficacy, 39.4%; 97.52% CI, -1.0 to 63.7; 95% CI, 5.3 to 61.2). The corresponding percentages for RSV-associated lower respiratory tract infection with severe hypoxemia were 0.5% and 1.0% (vaccine efficacy, 48.3%; 95% CI, -8.2 to 75.3), and the percentages for hospitalization for RSV-associated lower respiratory tract infection were 2.1% and 3.7% (vaccine efficacy, 44.4%; 95% CI, 19.6 to 61.5). Local injection-site reactions among the women were more common with vaccine than with placebo (40.7% vs. 9.9%), but the percentages of participants who had other adverse events were similar in the two groups. CONCLUSIONS: RSV F protein nanoparticle vaccination in pregnant women did not meet the prespecified success criterion for efficacy against RSV-associated, medically significant lower respiratory tract infection in infants up to 90 days of life. The suggestion of a possible benefit with respect to other end-point events involving RSV-associated respiratory disease in infants warrants further study. (Funded by Novavax and the Bill and Melinda Gates Foundation; ClinicalTrials.gov NCT02624947.).


Assuntos
Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano , Infecções Respiratórias/prevenção & controle , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Hipóxia/etiologia , Imunoglobulina G/sangue , Lactente , Recém-Nascido , Doenças do Recém-Nascido/prevenção & controle , Injeções Intramusculares , Nanopartículas , Distribuição de Poisson , Gravidez , Terceiro Trimestre da Gravidez , Infecções por Vírus Respiratório Sincicial/complicações , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano/imunologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Vacinação , Proteínas Virais de Fusão/imunologia , Adulto Jovem
10.
ACS Med Chem Lett ; 7(4): 403-7, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27096049

RESUMO

New securinine analogues have been prepared by semisynthesis. Two series were developed using either Suzuki or Sonogashira cross coupling reactions. The in vitro cytotoxicity of the compounds was assayed against HCT-116 colon cancer cells. The most potent derivatives showed promising growth inhibition on four tumoral cell lines giving a valuable insight on the structure-activity relationship (SAR) of securinine. Moreover, high antiproliferative effect against A-375 (melanoma) was observed with IC50 up to 60 nM.

11.
Eur J Med Chem ; 109: 287-93, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26793989

RESUMO

A series of new securinine analogues was prepared by Heck reaction from readily accessible securinine and commercially available iodoarenes. The in vitro cytotoxicity of the prepared compounds was assayed against a panel of four cancer cell lines: A375, A549, HCT-116 and HL-60 showing promising growth inhibition with excellent IC50 values in the nanomolar range. The plasmatic stability of the most potent analogue was also investigated demonstrating that they might serve as valuable leads for the development of anticancer drugs.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Azepinas/química , Azepinas/farmacologia , Compostos Heterocíclicos de Anel em Ponte/química , Compostos Heterocíclicos de Anel em Ponte/farmacologia , Lactonas/química , Lactonas/farmacologia , Piperidinas/química , Piperidinas/farmacologia , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Azepinas/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Euphorbiaceae/química , Compostos Heterocíclicos de Anel em Ponte/síntese química , Humanos , Lactonas/síntese química , Neoplasias/tratamento farmacológico , Piperidinas/síntese química
12.
Arch. argent. pediatr ; 108(5): 434-437, oct. 2010.
Artigo em Espanhol | LILACS | ID: lil-576260

RESUMO

El dolor no se puede explicar. Su comprensión no es posible si no lo es desde la más ingrata de las posiciones: su padecimiento. Así, en el intento por explicar sus múltiples apariciones, significados y mecanismos, surge como imprescindible el desarrollo de una filosofía del dolor. El acercamiento a estas cuestiones por parte de la medicina occidental tradicional, no ha tenido en cuenta el lenguaje particular en el que éstas se enmarcan, el cual se ve atravesado por una doble subjetividad: la que él mismo representa y la que encuadra a la relación entre los agentes por la que este lenguaje circula. La articulación de la medicina científica tradicional con disciplinas sociales, antropológicas y artísticas permitiría conformar una respuesta satisfactoria a esta doble subjetividad, con un profundo cambio enlas terapéuticas actuales del dolor.


Pain cannot be explained. It may only be understood from the most unpleasant of positions: suffering it. Thus, in the attempt to account for its multiple occurrences, meanings and mechanisms,developing a philosophy of pain appearsto be essential. The approach to these issues by traditional occidental medicine has not considered the particular language in their background, which contains a double subjectivity: the subjectivity it represents itself, and that which frames the relationship between the agents where this language circulates. Articulating traditionalscientific medicine with social, anthropological, and artistic disciplines would allow for a satisfactory response to this double subjectiveness, resultingin a deep change in current pain therapies.


Assuntos
Humanos , Masculino , Feminino , Dor/história , Dor/terapia , Medicina Tradicional , Relações Metafísicas Mente-Corpo , Filosofia Médica , Psicofisiologia
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