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1.
J Gen Virol ; 104(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37342971

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly emerged beta-coronavirus that enter cells via two routes, direct fusion at the plasma membrane or endocytosis followed by fusion with the late endosome/lysosome. While the viral receptor, ACE2, multiple entry factors and the mechanism of fusion of the virus at the plasma membrane have been investigated extensively, viral entry via the endocytic pathway is less understood. By using a human hepatocarcinoma cell line, Huh-7, which is resistant to the antiviral action of the TMPRSS2 inhibitor camostat, we discovered that SARS-CoV-2 entry is not dependent on dynamin but on cholesterol. ADP-ribosylation factor 6 (ARF6) has been described as a host factor for SARS-CoV-2 replication and is involved in the entry and infection of several pathogenic viruses. Using CRISPR/Cas9 genetic deletion, a modest reduction in SARS-CoV-2 uptake and infection in Huh-7 was observed. In addition, pharmacological inhibition of ARF6 with the small molecule NAV-2729 showed a dose-dependent reduction of viral infection. Importantly, NAV-2729 also reduced SARS-CoV-2 viral loads in more physiological models of infection: Calu-3 cells and kidney organoids. This highlighted a role for ARF6 in multiple cell contexts. Together, these experiments point to ARF6 as a putative target to develop antiviral strategies against SARS-CoV-2.


Assuntos
COVID-19 , Humanos , Fator 6 de Ribosilação do ADP , Antivirais/farmacologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus
2.
Med Oral Patol Oral Cir Bucal ; 27(5): e460-e467, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35717619

RESUMO

BACKGROUND: Peripheral Ossifying Fibroma (POF) is a reactive hyperplastic lesion that exclusively occurs in the gingiva and is characterized by the deposition of dystrophic calcification, cementum-like tissue, and immature and mature bone within the connective tissue. The objective of the present study was to perform a retrospective analysis of clinicopathologic features of POF. MATERIAL AND METHODS: Clinical and histopathological data were obtained from biopsy records and histopathological reports from a Brazilian reference service in Oral Pathology (1999 - 2020). Morphological analysis was performed to evaluate features related to the mesenchymal component, inflammatory infiltrate, ulceration, and mineralized tissue. RESULTS: A total of 270 POFs were diagnosed during the study period. A higher frequency was observed in females (71.9%) between the third (22.9%) and fourth (23.3%) decades of life. The anterior upper gingiva (29.1%) was the most affected region. Mature (86.7%) and immature (52.6%) bone tissue were the most frequent. There was a significant association between immature bone deposition and lesions with size ≤ 1.7 cm (p = 0.041); immature bone and cement-like tissue deposition with an evolution time ≤ 16 months (p < 0.001); deposition of immature bone and mesenchymal hypercellularization (p < 0.001); deposition of dystrophic calcification and the presence of ulceration (p < 0.001). CONCLUSIONS: The clinical characteristics corroborate the findings in the literature. The heterogeneous distribution and quantity of mineralized tissues found in the analyzed cases support the theory that the different mineralized tissues constitute a spectrum of clinical maturation of POF.


Assuntos
Fibroma Ossificante , Neoplasias Gengivais , Feminino , Fibroma Ossificante/patologia , Gengiva , Neoplasias Gengivais/patologia , Humanos , Hiperplasia/patologia , Estudos Retrospectivos
3.
bioRxiv ; 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-35702152

RESUMO

SARS-CoV-2 is a newly emerged beta-coronavirus that enter cells via two routes, direct fusion at the plasma membrane or endocytosis followed by fusion with the late endosome/lysosome. While the viral receptor, ACE2, multiple entry factors, and the mechanism of fusion of the virus at the plasma membrane have been extensively investigated, viral entry via the endocytic pathway is less understood. By using a human hepatocarcinoma cell line, Huh-7, which is resistant to the antiviral action of the TMPRSS2 inhibitor camostat, we discovered that SARS-CoV-2 entry is not dependent on dynamin but dependent on cholesterol. ADP-ribosylation factor 6 (ARF6) has been described as a host factor for SARS-CoV-2 replication and it is involved in the entry and infection of several pathogenic viruses. Using CRISPR-Cas9 genetic deletion, we observed that ARF6 is important for SARS-CoV-2 uptake and infection in Huh-7. This finding was corroborated using a pharmacologic inhibitor, whereby the ARF6 inhibitor NAV-2729 showed a dose-dependent inhibition of viral infection. Importantly, NAV-2729 reduced SARS-CoV-2 viral loads also in more physiologic models of infection: Calu-3 and kidney organoids. This highlighted the importance of ARF6 in multiple cell contexts. Together, these experiments points to ARF6 as a putative target to develop antiviral strategies against SARS-CoV-2.

6.
Brachytherapy ; 21(2): 229-237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35067466

RESUMO

PURPOSE: Nasopharyngeal brachytherapy is limited in part by the radiotolerance of nearby organs like the soft palate. This study explores several novel shielding designs for an intracavitary applicator to significantly reduce soft palate dose while adhering to the constraints of standard treatment procedure. METHODS: The Monte Carlo code TOPAS is used to characterize each prototype under typical high-dose-rate treatment conditions. Mucosal surface dose maps are collected to evaluate the shields on their dose reduction to the central and soft palate planning points and uniformity in their shielding profile. Practicality with respect to patient comfort and pretreatment imaging is discussed. History-by-history standard deviations are calculated for each simulation. RESULTS: A design with elliptical tubing containing bundles of tantalum wires provides the most significant attenuation with 39% and 27% dose reduction to the center and soft palate locations, respectively. Another design utilizing miniature lead spheres loaded into a constructed cavity shows 27% and 24% dose reduction to the same locations while providing more uniform shielding and several practical benefits. Both shields are designed to be completely removable for applicator insertion and pretreatment imaging. The mean and maximum standard error of relative dose measurements was 0.36 and 1.14 percentage points, respectively. CONCLUSION: Each shielding design presented in this study provides a novel approach to safely and effectively shield healthy tissue during intracavitary nasopharyngeal brachytherapy. Analysis performed using Monte Carlo suggests that the design using metal spheres most practically shields the soft palate and should be advanced to the next stages of clinical optimization.


Assuntos
Braquiterapia , Braquiterapia/métodos , Humanos , Método de Monte Carlo , Nasofaringe , Radiometria/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
7.
Med Oral Patol Oral Cir Bucal ; 27(1): e35-e41, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34564682

RESUMO

BACKGROUND: Angina bullosa haemorrhagica (ABH) is characterized by the recurrent appearance of blood blisters on the oral mucosa, mainly in adults' soft palate. In general, the blisters rupture spontaneously, lacking the necessity for biopsy. We report the clinical features of 23 ABH cases, emphasizing the clinical behavior and the management of these conditions. MATERIAL AND METHODS: A retrospective descriptive cross-sectional study was performed. A total of 12,727 clinical records of oral and maxillofacial lesions from four dental services in Brazil were analyzed. Clinical data were collected from the clinical records and evaluated. RESULTS: The series comprised 12 males (52.2%) and 11 females (47.8%), with a mean age of 56.8 ± 14.6 years (ranging: 24-82 years) and a 1.1:1 male-to-female ratio. Most of the lesions affected the soft palate (n = 15, 65.2%). Clinically, the lesions presented mainly as an asymptomatic (n = 17, 73.9%) blood-filled blister that ruptured after a few minutes or hours, leaving an erosion. The masticatory trauma was the most frequent triggering event. No patient had coagulation disorders. A biopsy was performed in only four cases (17.4%). Treatment was symptomatic with a favorable outcome. CONCLUSIONS: ABH is still poorly documented in the literature, and its etiology remains uncertain. ABH mainly affects the soft palate of elderly adults and has a favorable evolution in a few days. The therapeutic approach is often focused only on the relief of symptoms. However, it can share some clinical features with more serious diseases. Therefore, clinicians must recognize these lesions to avoid misdiagnosis.


Assuntos
Doenças da Boca , Hemorragia Bucal , Adulto , Idoso , Vesícula , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
J Med Phys ; 46(3): 135-139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703096

RESUMO

The inverse planning simulated annealing optimization engine was used to develop a new method of incorporating biological parameters into radiation treatment planning. This method integrates optimization of a radiation schedule over multiple types of delivery methods into a single algorithm. We demonstrate a general procedure of incorporating a functional biological dose model into the calculation of physical dose prescriptions. This paradigm differs from current practice in that it combines biology-informed dose constraints with a physical dose optimizer allowing for the comparison of treatment plans across multiple different radiation types and fractionation schemes.

9.
Cell Commun Signal ; 19(1): 86, 2021 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-34391444

RESUMO

BACKGROUND: Maspin (SERPINB5) is a potential tumor suppressor gene with pleiotropic biological activities, including regulation of cell proliferation, death, adhesion, migration and gene expression. Several studies indicate that nuclear localization is essential for maspin tumor suppression activity. We have previously shown that the EGFR activation leads to maspin nuclear localization in MCF-10A cells. The present study investigated which EGFR downstream signaling molecules are involved in maspin nuclear localization and explored a possible role of cell-cell contact in this process. METHODS: MCF-10A cells were treated with pharmacological inhibitors against EGFR downstream pathways followed by EGF treatment. Maspin subcellular localization was determined by immunofluorescence. Proteomic and interactome analyses were conducted to identify maspin-binding proteins in EGF-treated cells only. To investigate the role of cell-cell contact these cells were either treated with chelating agents or plated on different cell densities. Maspin and E-cadherin subcellular localization was determined by immunofluorescence. RESULTS: We found that PI3K-Akt and JAK2-STAT3, but not MAP kinase pathway, regulate EGF-induced maspin nuclear accumulation in MCF-10A cells. We observed that maspin is predominantly nuclear in sparse cell culture, but it is redistributed to the cytoplasm in confluent cells even in the presence of EGF. Proteomic and interactome results suggest a role of maspin on post-transcriptional and translation regulation, protein folding and cell-cell adhesion. CONCLUSIONS: Maspin nuclear accumulation is determined by an interplay between EGFR (via PI3K-Akt and JAK2-STAT3 pathways) and cell-cell contact. Video Abstract.


Assuntos
Comunicação Celular/genética , Janus Quinase 2/genética , Fator de Transcrição STAT3/genética , Serpinas/genética , Linhagem Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Proliferação de Células/genética , Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Fosfatidilinositol 3-Quinases/genética , Proteômica , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/genética
10.
Med Oral Patol Oral Cir Bucal ; 26(5): e676-e683, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34162820

RESUMO

BACKGROUND: Nasopalatine duct cyst (NDC) is the most common non-odontogenic cyst in the oral cavity. Clinically it is not difficult to suspect these lesions based on clinical and radiographic appearance. However, the histopathological diagnosis may be difficult due to the broad morphological diversity of these lesions. The objective was to analyze the clinicopathological features of NDCs diagnosed in two oral and maxillofacial pathology services in the Brazilian northeast. MATERIAL AND METHODS: A retrospective clinicopathologic study was performed. A total of 18,121 clinical records of oral lesions from two oral and maxillofacial pathology services in Brazil were analyzed (2000-2020). All NDCs cases were revised and demographic, clinical, radiographic, and histopathological data were collected. RESULTS: Among 18,121 diagnoses in the oral pathology services, 45 (0.2%) were NDCs. The series comprises 24 males (53.3%) and 21 females (46.7%), with a mean age of 43.2 years-old. Most lesions were asymptomatic (n = 27, 60%) with an mean size of 2.1 cm. Microscopically, the non-keratinized stratified squamous epithelium was the most common (66.7%). However, in 88.9% of cases, the epithelial lining was varied and composed of two or more types of epithelium. There was no significant association between the type of epithelium and the size of the cysts (p = 0.389). Nerve, blood vessels, hemorrhage, and chronic inflammatory infiltrate were commonly observed. In contrast, there was a low frequency of mucous glands, sebaceous glands, cholesterol clefts, and multinucleated giant cells. CONCLUSIONS: The clinical, radiographic, and microscopic findings observed in this study are similar to those reported in the literature. Due to the morphological diversity of NDC, it is needed to correlate its histopathological features with the clinical and radiographic findings to establish a correct diagnosis.


Assuntos
Cistos , Cistos não Odontogênicos , Adulto , Brasil , Cistos/diagnóstico por imagem , Cistos/epidemiologia , Feminino , Humanos , Masculino , Cistos não Odontogênicos/diagnóstico por imagem , Cistos não Odontogênicos/epidemiologia , Patologia Bucal , Encaminhamento e Consulta , Estudos Retrospectivos
11.
Pract Radiat Oncol ; 11(6): 515-526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34077809

RESUMO

PURPOSE: Salvage high-dose-rate brachytherapy (sHDRBT) for locally recurrent prostate cancer after definitive radiation is associated with biochemical control in approximately half of patients at 3 to 5 years. Given potential toxicity, patient selection is critical. We present our institutional experience with sHDRBT and validate a recursive partitioning machines model for biochemical control. MATERIALS AND METHODS: We performed a retrospective analysis of 129 patients who underwent whole-gland sHDRBT between 1998 and 2016. We evaluated clinical factors associated with biochemical control as well as toxicity. RESULTS: At diagnosis the median prostate-specific antigen (PSA) was 7.77 ng/mL. A majority of patients had T1-2 (73%) and Gleason 6-7 (82%) disease; 71% received external beam radiation therapy (RT) alone, and 22% received permanent prostate implants. The median disease-free interval (DFI) was 56 months, and median presalvage PSA was 4.95 ng/mL. At sHDRBT, 46% had T3 disease and 51% had Gleason 8 to 10 disease. At a median of 68 months after sHDRBT, 3- and 5-year disease-free survival were 85% (95% CI, 79-91) and 71% (95% CI, 62-79), respectively. Median PSA nadir was 0.18 ng/mL, achieved a median of 10 months after sHDRBT. Patients with ≥35%+ cores and a DFI <4.1 years had worse biochemical control (19% vs 50%, P = .02). Local failure (with or without regional/distant failure) was seen in 11% of patients (14/129), and 14 patients (11%) developed acute urinary obstruction requiring Foley placement and 19 patients (15%) developed strictures requiring dilation. CONCLUSIONS: sHDRBT is a reasonable option for patients with locally recurrent prostate cancer after definitive RT. Those with <35%+ cores or an initial DFI of ≥4.1 years may be more likely to achieve long-term disease control after sHDRBT.


Assuntos
Braquiterapia , Neoplasias da Próstata , Braquiterapia/efeitos adversos , Humanos , Masculino , Recidiva Local de Neoplasia/radioterapia , Antígeno Prostático Específico , Neoplasias da Próstata/radioterapia , Estudos Retrospectivos , Terapia de Salvação
12.
Animal ; 15(6): 100217, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34051433

RESUMO

Several nutritional strategies have been used in beef cattle production in order to increase animal performance and profitability. However, in the past two decades, the increase of consumer preference for functional foods has driven the investigation for improving food via adding functional substances to animal diets. We evaluated the effect of canola oil supplementation associated with vitamin E and selenium on performance, rumen metabolism, carcass traits, meat tenderness, and serum, liver, and meat status of antioxidants in finishing Nellore males. Animals were fed for 106 days in a feedlot and were randomly distributed in a 2 × 2 factorial arrangement: two levels of oil in the diet (no inclusion and 3% canola oil, defined as diet without oil inclusion (NO) and effect of oil (OIL), respectively) and two levels of antioxidants in the diet (no inclusion and 2.5 mg of Se/kg of DM + 500 UI of vitamin E/kg of DM, defined as diet without antioxidant inclusion (NA) and effect of the antioxidants (ANT), respectively). DM intake (kg/day) was evaluated daily; performance and serum were analysed at the beginning of the feedlot and every 28 days. Animals were slaughtered and hot carcass weight (kg) was recorded; ruminal fluid and liver samples were collected. At 24 h postmortem, carcass pH was recorded and the Longissimus thoracis was sampled. There was no significant effect of the OIL*ANT interaction (P > 0.05) for any trait evaluated. Bulls fed OIL presented greater final BW (P < 0.01), average daily gain (kg/day; P < 0.01), feed efficiency (P < 0.01), rump fat thickness (P8RF; P < 0.05), and greater tenderness; the ANT diet increased P8RF (P < 0.05). The levels of selenium and vitamin E in serum, liver, and meat were increased (P < 0.01) with the inclusion of ANT. ANT did not change triiodothyronine (T3, ng/mL) and thyroxine (T4, µg/gL) serum concentrations but decreased serum glucose levels. The treatments did not affect (P > 0.05) ruminal parameters or the protozoa population. Our results showed that the inclusion of 3% canola oil in the diet DM increased performance, feed efficiency, carcass fat deposition, and tenderness, with no effect on rumen fermentation and protozoa population of Nellore cattle in a feedlot system. The inclusion of ANT in the cattle diet did not affect performance or rumen parameters. However, the levels of ANT were increased in the serum, liver, and meat, enriching the final product with these compounds.


Assuntos
Ração Animal , Rúmen , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Composição Corporal , Bovinos , Dieta , Suplementos Nutricionais , Fermentação , Masculino , Óleo de Brassica napus/metabolismo , Rúmen/metabolismo
13.
Med Oral Patol Oral Cir Bucal ; 26(3): e284-e291, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32856618

RESUMO

BACKGROUND: Pigmented lesions are uncommon in the oral mucosa, and studies investigating the incidence and types of these lesions are desired to improve the diagnostic knowledge of clinicians. The aim of this study was to analyze the distribution of oral pigmented lesions in a Brazilian population. MATERIAL AND METHODS: A retrospective descriptive cross-sectional study was performed. Oral pigmented lesions were retrieved from the files of two oral and maxillofacial pathology services from Brazil over a 45-year period (1974-2019). The clinical data and the diagnoses of each case were retrieved and included in a Microsoft Excel® database. RESULTS: From 77.074 lesions diagnosed in this period, 761 (0.99%) represented pigmented lesions of the oral mucosa, including 351 (46.1%) melanocytic and 410 (53.9%) non-melanocytic lesions, with a higher incidence in females (73.2%) between the fourth and seventh decades of life. Amalgam tattoo (53.6%) represented the most common lesion, followed by melanotic macule (18.3%) and racial pigmentation (10.8%). Other pigmented lesions included nevus (9.9%), post-inflammatory pigmentation (3%), melanoma (2.1%), melanoacanthoma (1.4%), smoker's melanosis (0.4%), drug-induced pigmentation (0.3%), and melanotic neuroectodermal tumor of infancy (0.1%). The buccal mucosa was the most commonly affected site (25.2%), followed by the alveolar ridge (14.5%), and gingiva (11.8%). CONCLUSIONS: The current findings were similar to previous studies with minor differences due methodology and characteristics of the services from where lesions were retrieved. The knowledge of these data may contribute to a better understanding of oral pigmented lesions and assist clinicians to better recognize and manage them.


Assuntos
Doenças da Boca , Brasil/epidemiologia , Estudos Transversais , Diagnóstico Diferencial , Feminino , Humanos , Doenças da Boca/diagnóstico , Doenças da Boca/epidemiologia , Mucosa Bucal , Estudos Retrospectivos
14.
Med Oral Patol Oral Cir Bucal ; 26(3): e379-e386, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340079

RESUMO

BACKGROUND: Melanoma is an aggressive malignant tumor, rarely observed in the oral cavity. The aim of this study was to describe the clinicopathologic features of a series of oral melanomas. MATERIAL AND METHODS: A retrospective descriptive study was performed. A total of 15,482 biopsy records from two oral and maxillofacial pathology services in Brazil were analyzed. All cases of oral melanomas were reviewed, and clinical, demographic, histopathological data, treatment, and follow-up status were collected. In addition, immunohistochemistry stains (pan-cytokeratin AE1/AE3, vimentin, α-SMA, CD45, S-100 protein, HMB-45, Melan A, and Ki-67) were performed. RESULTS: The series comprised of 5 males (71.4%) and 2 females (28.6%), with a mean age of 58.0 ± 9.2 years (range: 45-69 years) and a 2.5:1 male-to-female ratio. The gingiva (n = 3, 42.8%) and hard palate (n = 2, 28.6%) were the most common affected sites, presenting clinically as ulcerated swellings with a brown to black color. Cervical lymph node metastasis was detected in three patients during the first examination. Microscopically, 6 cases (85.7%) were melanotic, and one (14.3%) was amelanotic. Most cases (n = 4, 57.1%) presented a predominance of epithelioid cells. S-100 and HMB-45 were positive in all cases (n = 7, 100.0%). In contrast, only 4 cases (57.1%) were positive for Melan-A. The proliferative index with Ki-67 was high, with labeling index ranging from 70.0% to more than 90% of positive cells. Five patients died from complications of the tumors after a mean follow-up period of 7.8 months. CONCLUSIONS: Melanoma is an aggressive malignant tumor that rarely occurs in the oral cavity. It occurs mainly in adult and elderly patients and often is diagnosed in advanced stages. The current findings were similar to previous studies and reflected the characteristics of the services from where lesions were retrieved.


Assuntos
Melanoma , Neoplasias Bucais , Adulto , Idoso , Brasil/epidemiologia , Feminino , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/epidemiologia , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Estudos Retrospectivos
15.
J Nutr Health Aging ; 24(8): 865-869, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33009537

RESUMO

AIM: Our aim in this study was to assess the clinical and metabolic impact of bariatric surgery in older adults. METHODS: This analytical, observational, longitudinal study was carried out with individuals aged 60 years and older who underwent bariatric surgery after 55 years of age at a specialist center for obesity management located in the Federal District of Brazil. Post-surgery changes in the following parameters from baseline: total body weight, excess weight lost, body mass index (BMI), number of medications, number of comorbidities, and weight regain. Mean values of the variables of interest before and after surgery were compared using the nonparametric Wilcoxon test, Poisson regression and multiple linear regression to test the effect of different variables. RESULTS: Overall, 74 subjects were assessed (78.3% female, mean age 65.8 ± 3.9 years). The mean time from bariatric surgery to assessment was 75.7 months. The mean weight and BMI in the overall sample at baseline was 101.9 ± 17.1 kg and 39.8 ± 4.9 kg/m², respectively. After the procedure, mean weight and BMI were reduced to 75.9 ± 12.9 kg and 29.4 ± 4.1 kg/m², respectively. Reductions were also achieved in mean number of medications used (P<0.001), number of comorbidities (P<0.001), triglyceride levels (P=0.007), and glycated hemoglobin (P=0.02). The mean HDL level increased significantly (P=0.008). CONCLUSION: In this sample, bariatric surgery was not only useful to manage obesity, but also reduced the number of comorbidities and medications used, and was associated with improvement in clinical and laboratory parameters.


Assuntos
Cirurgia Bariátrica/métodos , Obesidade Mórbida/cirurgia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
16.
Brachytherapy ; 19(5): 607-617, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32713779

RESUMO

PURPOSE: Currently in high-dose-rate (HDR) brachytherapy planning, manual fine-tuning of an objective function is a common practice. Furthermore, automated planning approaches such as multicriteria optimization (MCO) are still limited to the automatic generation of a single treatment plan. This study aims to quantify planning efficiency gains when using a graphics processing unit-based MCO (gMCO) algorithm combined with a novel graphical user interface (gMCO-GUI) that integrates efficient automated and interactive plan navigation tools. METHODS AND MATERIALS: The gMCO algorithm was used to generate 1000 Pareto optimal plans per case for 379 prostate cases. gMCO-GUI was developed to allow plan navigation through all plans. gMCO-GUI integrates interactive parameter selection tools directly with the optimization algorithm to allow plan navigation. The quality of each plan was evaluated based on the Radiation Treatment Oncology Group 0924 protocol and a more stringent institutional protocol (INSTp). gMCO-GUI allows real-time time display of the dose-volume histogram indices, the dose-volume histogram curves, and the isodose lines during the plan navigation. RESULTS: Over the 379 cases, the fraction of Radiation Treatment Oncology Group 0924 protocol valid plans with target coverage greater than 95% was 90.8%, compared with 66.0% for clinical plans. The fraction of INSTp valid plans with target coverage greater than 95% was 81.8%, compared with 62.3% for clinical plans. The average time to compute 1000 deliverable plans with gMCO was 12.5 s, including the full computation of the 3D dose distributions. CONCLUSIONS: Combining the gMCO algorithm with automated and interactive plan navigation tools resulted in simultaneous gains in both plan quality and planning efficiency.


Assuntos
Algoritmos , Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Masculino , Dosagem Radioterapêutica
17.
Med Oral Patol Oral Cir Bucal ; 25(4): e516-e522, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32388524

RESUMO

BACKGROUND: Salivary gland tumors (SGT) correspond to a heterogeneous group of lesions with variable biological behavior. The present study aimed to determine the distribution and demographic findings of salivary gland neoplasms in a northeast Brazilian population. MATERIAL AND METHODS: A retrospective descriptive cross-sectional study was performed. A total of 588 cases of SGT were diagnosed between 2006 and 2016 of 4 pathology services in the state of Sergipe, Brazil. All cases were reviewed, and data such as sex, age, anatomical location, and histopathological diagnosis were collected. RESULTS: A total of 470 (79.9%) tumors were benign and 118 (20.1%) were malignant. The majority of the patients were females (n=328, 55.8%) with an overall female:male ratio of 1.2:1. The major salivary glands were affected more than the minor glands (69.5% vs. 30.5%). Pleomorphic adenoma (n=419, 71.3%) and mucoepidermoid carcinoma (n=29, 4.9%) were the most frequent benign and malignant tumors, respectively. In addition, both benign and malignant tumors occurred more frequently in the parotid gland (n=300, 51%, p<0.05). CONCLUSIONS: The epidemiologic profile and clinical characteristics of SGT were similar to those described in other countries and other regions of Brazil. Epidemiological studies of SGT help to understand their clinical and pathological features and are essential to establish the proper management and prognosis.


Assuntos
Adenoma Pleomorfo , Neoplasias das Glândulas Salivares , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Retrospectivos
18.
Int J Radiat Oncol Biol Phys ; 107(5): 887-896, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32339646

RESUMO

PURPOSE: To investigate use of a novel imaging approach, hyperpolarized (HP) 13C magnetic resonance imaging (MRI) for simultaneous metabolism and perfusion assessment, to evaluate early and dose-dependent response to radiation therapy (RT) in a prostate cancer mouse model. METHODS AND MATERIALS: Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) mice (n = 18) underwent single-fraction RT (4-14 Gy steep dose across the tumor) and were imaged serially at pre-RT baseline and 1, 4, and 7 days after RT using HP 13C MRI with combined [1-13C]pyruvate (metabolic active agent) and [13C]urea (perfusion agent), coupled with conventional multiparametric 1H MRI including T2-weighted, dynamic contrast-enhanced, and diffusion-weighted imaging. Tumor tissues were collected 4 and 7 days after RT for biological correlative studies. RESULTS: We found a significant decrease in HP pyruvate-to-lactate conversion in tumors responding to RT, with concomitant significant increases in HP pyruvate-to-alanine conversion and HP urea signal; the opposite changes were observed in tumors resistant to RT. Moreover, HP lactate change was dependent on radiation dose; tumor regions treated with higher radiation doses (10-14 Gy) exhibited a greater decrease in HP lactate signal than low-dose regions (4-7 Gy) as early as 1 day post-RT, consistent with lactate dehydrogenase enzyme activity and expression data. We also found that HP [13C]urea MRI provided assessments of tumor perfusion similar to those provided by 1H dynamic contrast-enhanced MRI in this animal model. However, apparent diffusion coefficien , a conventional 1H MRI functional biomarker, did not exhibit statistically significant changes within 7 days after RT. CONCLUSION: These results demonstrate the ability of HP 13C MRI to monitor radiation-induced physiologic changes in a timely and dose-dependent manner, providing the basic science premise for further clinical investigation and translation.


Assuntos
Imageamento por Ressonância Magnética , Imagem de Perfusão , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Animais , Isótopos de Carbono , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Masculino , Camundongos , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/metabolismo , Ácido Pirúvico , Fatores de Tempo , Resultado do Tratamento , Ureia
19.
Pulmonology ; 26(1): 10-17, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31630986

RESUMO

OBJECTIVE: The main aim of the study was to evaluate the efficacy and safety profile of Nivolumab, an immune-checkpoint-inhibitor antibody, in advanced, previously treated, Non-Small Cell Lung Cancer (NSCLC) patients, in a real world setting. METHODS: We performed a retrospective, multicentre data analysis of patients who were included in the Portuguese Nivolumab Expanded Access Program (EAP). Eligibility criteria included histologically or citologically confirmed NSCLC, stage IIIB and IV, evaluable disease, sufficient organ function and at least one prior line of chemotherapy. The endpoints included Overall Response Rate (ORR), Disease Control Rate (DCR), Progression Free Survival (PFS) and Overall Survival (OS). Safety analysis was performed with the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 4.0, and immune-related Adverse Events (irAEs) were treated according to protocol treatment guidelines. Tumour response was assessed using the Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. Data was analysed using SPSS, version 21.0 (IBM Statistics). RESULTS: From June 2015 to December 2016, a total of 229 patients with advanced NSCLC were enrolled at 30 Portuguese centres. Clinical data were collected up to the end of July 2018. The baseline median age was 64 years (range 37-83) and the majority of patients were males (70.3%) and former/current smokers (69.4%). Patients with non-squamous histology predominated (88.1%), and 67.6% of the patients had received 2 or more prior lines of chemotherapy. Out of 229 patients, data was available for 219 patients (3 patients did not start treatment, while data was unavailable in 7 patients); of the 219 patients, 15.5% were not evaluated for radiological tumour assessment, 1.4% had complete response (CR), 21% partial response (PR), 31% stable disease (SD) and 31.1% progressive disease (PD). Thus, the ORR was 22.4% and DCR was 53.4% in this population. At the time of survival analysis the median PFS was 4.91 months (95% CI, 3.89-6.11) and median OS was 13.21 months (95% CI, 9.89-16.53). The safety profile was in line with clinical trial data. CONCLUSIONS: Efficacy and safety results observed in this retrospective analysis were consistent with observations reported in clinical trials and from other centres.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Feminino , Humanos , Incidência , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Intervalo Livre de Progressão , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento
20.
Semin Radiat Oncol ; 30(1): 94-106, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31727305

RESUMO

Brachytherapy has advanced dramatically in the last decade due largely to improvements in applicators, imaging, treatment planning, and use of clinical trials. In addition, current research in brachytherapy technology continues to change how we deliver this treatment modality. The future of brachytherapy lies in the ability of new technologies to overcome real or perceived barriers. The focus for this manuscript is on specific tools that have or are near to being introduced in the clinic. First, we explore the impact electromagnetic tracking technologies can have on brachytherapy implants and planning workflow. This is followed by an overview of the use of 3D printing and its ability to help tailor brachytherapy implants. Next, we discuss advances in self-shielded applicators and intensity-modulated brachytherapy technology. The manuscript closes out with 2 sections on treatment planning. First is a discussion of biological optimization and its potential as compared with current techniques (eg, based on physical dosimetry). And lastly, a section on optimization treatment planning efficiencies in which we explore the potential for machine learning in brachytherapy. As recent clinical evidence continues to show excellent outcomes, this is an exciting time to practice brachytherapy. With the new technologies presented here, the future is even brighter.


Assuntos
Braquiterapia/tendências , Braquiterapia/métodos , Fenômenos Eletromagnéticos , Feminino , Humanos , Masculino , Neoplasias/radioterapia , Impressão Tridimensional , Próteses e Implantes , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem , Fluxo de Trabalho
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