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1.
Blood ; 141(11): 1322-1336, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36399711

RESUMO

Venous thromboembolism (VTE) is a life-threating condition that is common in patients with adult-type diffuse gliomas, yet thromboprophylaxis is controversial because of possible intracerebral hemorrhage. Effective VTE prediction models exist for other cancers, but not glioma. Our objective was to develop a VTE prediction tool to improve glioma patient care, incorporating clinical, blood-based, histologic, and molecular markers. We analyzed preoperative arterial blood, tumor tissue, and clinical-pathologic data (including next-generation sequencing data) from 258 patients with newly diagnosed World Health Organization (WHO) grade 2 to 4 adult-type diffuse gliomas. Forty-six (17.8%) experienced VTE. Tumor expression of tissue factor (TF) and podoplanin (PDPN) each positively correlated with VTE, although only circulating TF and D-dimers, not circulating PDPN, correlated with VTE risk. Gliomas with mutations in isocitrate dehydrogenase 1 (IDH1) or IDH2 (IDHmut) caused fewer VTEs; multivariable analysis suggested that this is due to IDHmut suppression of TF, not PDPN. In a predictive time-to-event model, the following predicted increased VTE risk in newly diagnosed patients with glioma: (1) history of VTE; (2) hypertension; (3) asthma; (4) white blood cell count; (5) WHO tumor grade; (6) patient age; and (7) body mass index. Conversely, IDHmut, hypothyroidism, and MGMT promoter methylation predicted reduced VTE risk. These 10 variables were used to create a web-based VTE prediction tool that was validated in 2 separate cohorts of patients with adult-type diffuse glioma from other institutions. This study extends our understanding of the VTE landscape in these tumors and provides evidence-based guidance for clinicians to mitigate VTE risk in patients with glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Tromboembolia Venosa , Humanos , Adulto , Tromboembolia Venosa/genética , Tromboembolia Venosa/diagnóstico , Anticoagulantes/uso terapêutico , Glioma/complicações , Glioma/genética , Glioma/tratamento farmacológico , Biomarcadores , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Isocitrato Desidrogenase/genética , Mutação
2.
Sensors (Basel) ; 23(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36679833

RESUMO

Shipping traffic is recognised as the main man-noise source of the anthropogenic noise generated in the marine environment. The underwater acoustic pollution is increased due to the increment of the human activity at seas supposing a threat for marine habitats. The ship as acoustic source must be understood and controlled to manage the maritime areas both in time and space to reduce the impact of noise in marine fauna. Shipping noise is mainly composed of flow noise, propeller noise and machinery noise. This research is focused on the analysis and estimation of the underwater radiated noise generated by the vibrations of the onboard machinery or structure-borne noise based on the calculation of the transfer function. This function relates the acceleration levels of the vibrations of the hull's panels and the radiated noise by them using the radiation efficiency. Different analytical methods to estimate the radiation efficiency are presented and compared with data collected at sea. The measurements are performed acquiring simultaneously acceleration and acoustic levels by means on accelerometers installed on the hull's panels at different positions and hydrophones deployed close to the bow, middle and stern of the ship. The analysis of the transmission of the vibrations along the ships is performed using the data from different locations of the hydrophones. The quality of the measurements is analysed using the coherence function through the spectral correlation between the measurement of vibrations and acoustic levels. On the other hand, signal-to-noise ratio is computed to verify the strength of the noise sources. The computed transfer function is used to predict the underwater radiated noise from vibrations showing differences less than 2 dB re to 1 µPa2.


Assuntos
Navios , Vibração , Humanos , Ruído , Oceanos e Mares , Acústica
3.
J Clin Invest ; 133(12)2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37104042

RESUMO

Seizures are a frequent complication of adult-type diffuse gliomas, and are often difficult to control with medications. Gliomas with mutations in isocitrate dehydrogenase 1 or 2 (IDHmut) are more likely than IDH-wild type (IDHwt) gliomas to cause seizures as part of their initial clinical presentation. However, whether IDHmut is also associated with seizures during the remaining disease course, and whether IDHmut inhibitors can reduce seizure risk, are unclear. Clinical multivariable analyses showed that preoperative seizures, glioma location, extent of resection, and glioma molecular subtype (including IDHmut status) all contributed to postoperative seizure risk in adult-type diffuse glioma patients, and that postoperative seizures were often associated with tumor recurrence. Experimentally, the metabolic product of IDHmut, d-2-hydroxyglutarate, rapidly synchronized neuronal spike firing in a seizure-like manner, but only when non-neoplastic glial cells were present. In vitro and in vivo models recapitulated IDHmut glioma-associated seizures, and IDHmut inhibitors currently being evaluated in glioma clinical trials inhibited seizures in those models, independent of their effects on glioma growth. These data show that postoperative seizure risk in adult-type diffuse gliomas varies in large part by molecular subtype, and that IDHmut inhibitors could play a key role in mitigating such risk in IDHmut glioma patients.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Recidiva Local de Neoplasia , Glioma/tratamento farmacológico , Glioma/genética , Glioma/patologia , Convulsões/tratamento farmacológico , Convulsões/genética , Progressão da Doença , Isocitrato Desidrogenase/genética , Mutação
4.
PLoS One ; 17(2): e0257725, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35134075

RESUMO

Infiltrative gliomas are the most common neoplasms arising in the brain, and remain largely incurable despite decades of research. A subset of these gliomas contains mutations in isocitrate dehydrogenase 1 (IDH1mut) or, less commonly, IDH2 (together called "IDHmut"). These mutations alter cellular biochemistry, and IDHmut gliomas are generally less aggressive than IDH wild-type (IDHwt) gliomas. Some preclinical studies and clinical trials have suggested that various forms of a ketogenic diet (KD), characterized by low-carbohydrate and high-fat content, may be beneficial in slowing glioma progression. However, adherence to a strict KD is difficult, and not all studies have shown promising results. Furthermore, no study has yet addressed whether IDHmut gliomas might be more sensitive to KD. The aim of the current study was to compare the effects of a unrestricted, cycling KD (weekly alternating between KD and standard diet) in preclinical models of IDHwt versus IDHmut gliomas. In vitro, simulating KD by treatment with the ketone body ß-hydroxybutyrate had no effect on the proliferation of patient-derived IDHwt or IDHmut glioma cells, either in low or normal glucose conditions. Likewise, an unrestricted, cycling KD had no effect on the in vivo growth of patient-derived IDHwt or IDHmut gliomas, even though the cycling KD did result in persistently elevated circulating ketones. Furthermore, this KD conferred no survival benefit in mice engrafted with Sleeping-Beauty transposase-engineered IDHmut or IDHwt glioma. These data suggest that neither IDHwt nor IDHmut gliomas are particularly responsive to an unrestricted, cycling form of KD.


Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Proliferação de Células/efeitos dos fármacos , Dieta Cetogênica , Glioma/patologia , Isocitrato Desidrogenase/genética , Animais , Glicemia/análise , Linhagem Celular Tumoral , Glioma/dietoterapia , Glioma/genética , Glioma/mortalidade , Glucose/farmacologia , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Nus , Mutação , Transplante Heterólogo
5.
Acta Neuropathol Commun ; 8(1): 15, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051040

RESUMO

A subset of gliomas has DNA repair defects that lead to hypermutated genomes. While such tumors are resistant to alkylating chemotherapies, they may also express more mutant neoantigens on their cell surfaces, and thus be more responsive to immunotherapies. A fast, inexpensive method of screening for hypermutated gliomas would therefore be of great clinical value. Since immunohistochemistry (IHC) for the DNA mismatch repair (MMR) proteins Msh2, Msh6, Mlh1, and Pms2 is already used to screen for hypermutated colorectal cancers, we sought to determine whether that panel might have similar utility in gliomas. MMR IHC was scored in 100 WHO grade I-IV gliomas (from 96 patients) with known tumor mutation burden (TMB), while blinded to TMB data. Cases included 70 grade IV GBMs, 13 grade III astrocytomas, 4 grade II astrocytomas (3 diffuse astrocytomas and 1 pleomorphic xanthoastrocytoma), 1 grade I pilocytic astrocytoma, 2 grade III oligodendrogliomas, 7 grade II oligodendrogliomas, and 3 grade I glioneuronal tumors. Eight of 100 tumors showed loss of one or more MMR proteins by IHC, and all 8 were hypermutated. Among the remaining 92 gliomas with intact MMR IHC, only one was hypermutated; that tumor had an inactivating mutation in another DNA repair gene, ATM. Overall accuracy, sensitivity, and specificity for DNA MMR IHC compared to the gold standard of TMB were 99, 89, and 100%, respectively. The strongest correlates with hypermutation were prior TMZ treatment, MGMT promoter methylation, and IDH1 mutation. Among the 8 MMR-deficient hypermutated gliomas, 4 (50%) contained both MMR-lost and MMR-retained tumor cells. Together, these data suggest that MMR IHC could be a viable front-line screening test for gliomas in which immunotherapy is being considered. They also suggest that not all cells in a hypermutated glioma may actually be MMR-deficient, a finding that might need to be considered when treating such tumors with immunotherapies.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Reparo de Erro de Pareamento de DNA , Detecção Precoce de Câncer/métodos , Glioma/diagnóstico , Glioma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Proteínas de Ligação a DNA/genética , Feminino , Glioma/enzimologia , Glioma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Proteína 1 Homóloga a MutL/genética , Proteína 2 Homóloga a MutS/genética , Gradação de Tumores , Sensibilidade e Especificidade , Adulto Jovem
6.
Nat Ecol Evol ; 4(6): 870-884, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32393869

RESUMO

Prostate cancer (PCa) progression is a complex eco-evolutionary process driven by the feedback between evolving tumour cell phenotypes and microenvironmentally driven selection. To better understand this relationship, we used a multiscale mathematical model that integrates data from biology and pathology on the microenvironmental regulation of PCa cell behaviour. Our data indicate that the interactions between tumour cells and their environment shape the evolutionary dynamics of PCa cells and explain overall tumour aggressiveness. A key environmental determinant of this aggressiveness is the stromal ecology, which can be either inhibitory, highly reactive (supportive) or non-reactive (neutral). Our results show that stromal ecology correlates directly with tumour growth but inversely modulates tumour evolution. This suggests that aggressive, environmentally independent PCa may be a result of poor stromal ecology, supporting the concept that purely tumour epithelium-centric metrics of aggressiveness may be incomplete and that incorporating markers of stromal ecology would improve prognosis.


Assuntos
Neoplasias da Próstata , Células Estromais , Humanos , Masculino
7.
Neuro Oncol ; 22(4): 470-479, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31711239

RESUMO

BACKGROUND: Progress in extending the survival of glioblastoma (GBM) patients has been slow. A better understanding of why patient survival remains poor is critical to developing new strategies. Postmortem studies on GBM can shed light on why patients are dying. METHODS: The brains of 33 GBM patients were autopsied and examined for gross and microscopic abnormalities. Clinical-pathologic correlations were accomplished through detailed chart reviews. Data were compared with older published autopsy GBM studies that predated newer treatment strategies, such as more extensive surgical resection and adjuvant temozolomide. RESULTS: In older GBM autopsy series, mass effect was observed in 72% of brains, with herniation in 50% of all cases. Infiltration of tumor into the brainstem was noted in only 21% of those older cases. In the current series, only 10 of 33 (30%) GBMs showed mass effect (P = 0.0003), and only 1 (3%) showed herniation (P < 0.0001). However, extensive GBM infiltration of the brainstem was present in 22 cases (67%, P < 0.0001), with accompanying destruction of the pons and white matter tracts. There was a direct correlation between longer median patient survival and the presence of brainstem infiltration (16.1 mo in brainstem-invaded cases vs 9.0 mo in cases lacking extensive brainstem involvement; P = 0.0003). CONCLUSIONS: With improving care, severe mass effect appears to be less common in GBM patients today, whereas dissemination, including life-threatening brainstem invasion, is now more pronounced. This has major implications regarding preclinical GBM models, as well as the design of clinical trials aimed at further improving patient survival.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Supratentoriais , Idoso , Tronco Encefálico , Humanos , Temozolomida
8.
Clin Cancer Res ; 25(2): 747-759, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30266764

RESUMO

PURPOSE: Gliomas with isocitrate dehydrogenase 1 mutations (IDH1mut) are less aggressive than IDH1 wild-type (IDH1wt) gliomas and have global genomic hypermethylation. Yet it is unclear how specific hypermethylation events contribute to the IDH1mut phenotype. Previously, we showed that the gene encoding the procoagulant tissue factor (TF), F3, is among the most hypermethylated and downregulated genes in IDH1mut gliomas, correlating with greatly reduced thrombosis in patients with IDH1mut glioma. Because TF also increases the aggressiveness of many cancers, the current study explored the contribution of TF suppression to the reduced malignancy of IDH1mut gliomas.Experimental Design: TF expression was manipulated in patient-derived IDH1mut and IDH1wt glioma cells, followed by evaluation of in vitro and in vivo behavior and analyses of cell signaling pathways. RESULTS: A demethylating agent, decitabine, increased F3 transcription and TF-dependent coagulative activity in IDH1mut cells, but not in IDH1wt cells. TF induction enhanced the proliferation, invasion, and colony formation of IDH1mut cells, and increased the intracranial engraftment of IDH1mut GBM164 from 0% to 100% (P = 0.0001). Conversely, TF knockdown doubled the median survival of mice engrafted with IDH1wt/EGFRvIIIamp GBM6, and caused complete regression of IDH1wt/EGFRamp GBM12 (P = 0.001). In vitro and in vivo effects were linked to activation of receptor tyrosine kinases (RTK) by TF through a Src-dependent intracellular pathway, even when extracellular RTK stimulation was blocked. TF stimulated invasion predominately through upregulation of ß-catenin. CONCLUSIONS: These data show that TF suppression is a component of IDH1mut glioma behavior, and that it may therefore be an attractive target against IDH1wt gliomas.


Assuntos
Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Isocitrato Desidrogenase/genética , Mutação , Tromboplastina/genética , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Expressão Ectópica do Gene , Epigênese Genética , Técnicas de Silenciamento de Genes , Glioma/metabolismo , Humanos , Isocitrato Desidrogenase/metabolismo , Camundongos , Gradação de Tumores , Ligação Proteica , Proteômica/métodos , Tromboplastina/metabolismo , Ativação Transcricional , Ensaio Tumoral de Célula-Tronco
9.
Diagn Pathol ; 13(1): 37, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29871654

RESUMO

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is an uncommon tumor in the brain. Although most PCNSL are readily diagnosed as diffuse large B cell lymphoma (DLBCL) on the first biopsy, very rare cases have been described in which the first detected intracerebral lesions are non-neoplastic, and are composed mostly of perivascular T cells, not B cells. This phenomenon is known as "sentinel lesions."


Assuntos
Linfócitos B/patologia , Neoplasias Encefálicas/patologia , Linfoma Difuso de Grandes Células B/patologia , Lesões Pré-Cancerosas/patologia , Humanos , Masculino , Pessoa de Meia-Idade
10.
Cancer Res ; 78(21): 6134-6145, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30181178

RESUMO

Progress in prostate cancer racial disparity research has been hampered by a lack of appropriate research tools and better understanding of the tumor biology. Recent gene expression studies suggest that the tumor microenvironment (TME) may contribute to racially disparate clinical outcomes in prostate cancer. Analysis of the prostate TME has shown increased reactive stroma associated with chronic inflammatory infiltrates in African-American (AA) compared with European-American (EA) patients with prostate cancer. To better understand stromal drivers of changes in TME, we isolated prostate fibroblasts (PrF) from AA (PrF-AA) and EA (PrF-EA) prostate cancer tissues and studied their functional characteristics. PrF-AA showed increased growth response to androgens FGF2 and platelet-derived growth factor. Compared with PrF-EA, conditioned media from PrF-AA significantly enhanced the proliferation and motility of prostate cancer cell lines. Expression of markers associated with myofibroblast activation (αSMA, vimentin, and tenascin-C) was elevated in PrF-AA In vivo tumorigenicity of an AA patient-derived prostatic epithelial cell line E006AA was significantly increased in the presence of PrF-AA compared with PrF-EA, and RNA-seq data and cytokine array analysis identified a panel of potential proinflammatory paracrine mediators (BDNF, CHI3L1, DPPIV, FGF7, IL18BP, IL6, and VEGF) to be enriched in PrF-AA E006AA cell lines showed increased responsiveness to BDNF ligand compared with EA-derived LNCaP and C4-2B cells. Addition of a TrkB-specific antagonist significantly reduced the protumorigenic effects induced by PrF-AA compared with PrF-EA These findings suggest that fibroblasts in the TME of AA patients may contribute to the health disparity observed in the incidence and progression of prostate cancer tumors.Significance: These findings suggest that stromal cells in the tumor microenvironment of African-American men promote progression of prostate cancer by increasing levels of a specific set of pro-inflammatory molecules compared with European-American men.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/21/6134/F1.large.jpg Cancer Res; 78(21); 6134-45. ©2018 AACR.


Assuntos
Inflamação/etnologia , Inflamação/patologia , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/patologia , Células Estromais/metabolismo , Negro ou Afro-Americano , Idoso , Carcinogênese , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citocinas/metabolismo , Progressão da Doença , Células Epiteliais , Fibroblastos/metabolismo , Humanos , Inflamação/complicações , Mediadores da Inflamação/metabolismo , Ligantes , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Neoplasias da Próstata/complicações , Microambiente Tumoral
11.
Trials ; 18(1): 134, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28327195

RESUMO

BACKGROUND: Laparoscopic training has become an important part of surgical education. Laparoscopic Roux-en-Y gastric bypass (RYGB) is the most common bariatric procedure performed. Surgeons must be well trained prior to operating on a patient. Multimodality training is vital for bariatric surgery. E-learning with videos is a standard approach for training. The present study investigates whether scoring the operation videos with performance checklists improves learning effects and transfer to a simulated operation. METHODS/DESIGN: This is a monocentric, two-arm, randomized controlled trial. The trainees are medical students from the University of Heidelberg in their clinical years with no prior laparoscopic experience. After a laparoscopic basic virtual reality (VR) training, 80 students are randomized into one of two arms in a 1:1 ratio to the checklist group (group A) and control group without a checklist (group B). After all students are given an introduction of the training center, VR trainer and laparoscopic instruments, they start with E-learning while watching explanations and videos of RYGB. Only group A will perform ratings with a modified Bariatric Objective Structured Assessment of Technical Skill (BOSATS) scale checklist for all videos watched. Group B watches the same videos without rating. Both groups will then perform an RYGB in the VR trainer as a primary endpoint and small bowel suturing as an additional test in the box trainer for evaluation. DISCUSSION: This study aims to assess if E-learning and rating bariatric surgical videos with a modified BOSATS checklist will improve the learning curve for medical students in an RYGB VR performance. This study may help in future laparoscopic and bariatric training courses. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00010493 . Registered on 20 May 2016.


Assuntos
Lista de Checagem , Instrução por Computador , Educação de Graduação em Medicina/métodos , Derivação Gástrica/educação , Laparoscopia/educação , Treinamento por Simulação/métodos , Estudantes de Medicina , Gravação em Vídeo , Competência Clínica , Protocolos Clínicos , Currículo , Alemanha , Humanos , Curva de Aprendizado , Estudos Prospectivos , Projetos de Pesquisa , Técnicas de Sutura/educação , Análise e Desempenho de Tarefas
12.
Gac. méd. boliv ; 40(1): 21-23, jun. 2017. ilus, graf, map, tab
Artigo em Espanhol | LILACS | ID: biblio-892323

RESUMO

Objetivo: establecer la prevalencia de serología positiva por ELISA IgG para Brucella spp y conocer la relación con factores asociados. Métodos: se realizaron ELISA IgG en 276 muestras del Banco de Sangre de Referencia - Cochabamba. Resultados: obtuvimos una prevalencia de 10,87/1 000 habitantes. Conclusiones: los datos de prevalencia obtenidos son congruentes con los reportados por otros países a nivel mundial.


Objective: to establish positive ELISA IgG seroprevalence for Brucella spp and to find associated risk factors. Method: 276 samples provided by the Banco de Sangre de Referencia - Cochabamba" underwent IgG ELISA. Results: we obtained a 10.87/1 000 prevalence rate result.Conclusions: data obtained by this study is consistent with the one reported by country worldwide.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Brucella , Ensaio de Imunoadsorção Enzimática , Estudos Transversais
16.
Pediatría (Bogotá) ; 34(4): 288-91, nov. 1999. tab
Artigo em Espanhol | LILACS | ID: lil-293535

RESUMO

Para evaluar la situación de niños preescolares en las instituciones del Distrito de Bogotá, que prestan servicios de este tipo de población; se tomaron 237 niños con edades entre 24 y 76 meses, se estudiaron ellos con respecto a la prevalencia de parasitismo intestinal, la situación nutricional por medio de la evaluación de peso y talla, la circunferencia del brazo, el espesor del pliegue del tríceps y los parámetros angíneos de hemogrobina y hematocrito. Así mismo se tomó información social, ambiental, de conocimiento y hábitos de los familiares de los niños. Ascaris y tricocéfalos se encontraron en una frecuencia del 0.5 por ciento, mientras que la entamoeba histyolitica se encontró en 3.5 por ciento y giardia lamblia en el 14.9 por ciento. Se encontró desnutrición crónica y global del 45.5 por ciento y 38.8 por ciento respectivamente. Los parámetros nutricionales en sangre estuvieron dentro de los límites normales. Las variables sociales y ambientales no presentaron alteraciones de importancia. Mientras los hábitos básicos de higiene resultaron adecuados, el nivel de conocimiento sobre prevención de los parásitos por parte de los padres y familiares fue precario. Se examina la posible significación de estos resultados.


Assuntos
Humanos , Criança , Avaliação Nutricional , Estado Nutricional , Doenças Parasitárias/diagnóstico , Doenças Parasitárias/etiologia , Doenças Parasitárias/fisiopatologia
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