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1.
Curr Oncol ; 22(2): e76-84, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25908924

RESUMO

BACKGROUND: Dose-escalated hypofractionated radiotherapy (hfrt) using intensity-modulated radiotherapy (imrt), with inclusion of the pelvic lymph nodes (plns), plus androgen suppression therapy (ast) in high-risk prostate cancer patients should improve patient outcomes, but acute toxicity could limit its feasibility. METHODS: Our single-centre phase ii prospective study enrolled 40 high-risk prostate cancer patients. All patients received hfrt using imrt with daily mega-voltage computed tomography imaging guidance, with 95% of planning target volumes (ptv68 and ptv50) receiving 68 Gy and 50 Gy (respectively) in 25 daily fractions. The boost volume was targeted to the involved plns and the prostate (minus the urethra plus 3 mm and minus 3 mm from adjacent rectal wall) and totalled up to 75 Gy in 25 fractions. Acute toxicity scores were recorded weekly during and 3 months after radiotherapy (rt) administration. RESULTS: For the 37 patients who completed rt and the 3-month follow-up, median age was 65.5 years (range: 50-76 years). Disease was organ-confined (T1c-T2c) in 23 patients (62.1%), and node-positive in 5 patients (13.5%). All patients received long-term ast. Maximum acute genitourinary (gu) and gastrointestinal (gi) toxicity peaked at grade 2 in 6 of 36 evaluated patients (16.6%) and in 4 of 31 evaluated patients (12.9%) respectively. Diarrhea and urinary frequency were the chief complaints. Dose-volume parameters demonstrated no correlation with toxicity. The ptv treatment objectives were met in 36 of the 37 patients. CONCLUSIONS: This hfrt dose-escalation trial in high-risk prostate cancer has demonstrated the feasibility of administering 75 Gy in 25 fractions with minimal acute gi and gu toxicities. Further follow-up will report late toxicities and outcomes.

2.
Curr Oncol ; 20(5): 258-64, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24155630

RESUMO

BACKGROUND: Small-cell carcinomas (sccs) of the genitourinary (gu) tract are rare systemic diseases, and there is no standard treatment strategy for patients with this malignancy. The objectives of the present study were to report the management and outcome of patients with scc of the gu tract treated at a tertiary-care institution from 1982 to 2009. METHODS: In a chart review of all patients diagnosed with scc of the gu tract between 1982 and 2009, data on demographics, clinical and pathologic characteristics, treatment, and patient outcomes were collected. RESULTS: The 58 patients identified had scc in the following primary sites: urinary bladder (n = 35), prostate (n = 17), and upper urinary tract (n = 6). In 38 patients (66%), the scc was of pure histology; in the remainder, histology was mixed. Overall, 28 patients had limited-stage disease; 24 had extensive-stage disease; and staging was unknown in 6 patients. Median survival for the entire cohort was 7.5 months, with extensive-stage disease being identified as a poor prognostic factor (survival was 22.0 months for limited-stage patients and 4.1 months for extensive-stage patients, p < 0.001). Based on site, prostate patients fared worst, with a median survival of only 5.1 months. Compared with best supportive care, treatment was associated with better outcomes (median survival: 12.3 months vs. 2.3 months, p < 0.0001). CONCLUSIONS: Small-cell cancer of the gu tract is an aggressive cancer, with a poor prognosis overall. Although there is no standard of care, patients should be treated using a multimodality approach analogous to that used in the treatment of small-cell lung cancer.

3.
Curr Oncol ; 20(2): 104-10, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23559873

RESUMO

PURPOSE: The objective of the present study was to analyze, with relatively high sensitivity and specificity, uptake properties of [(11)C]-choline in prostate cancer patients by means of positron-emission tomography (pet)/computed tomography (ct) imaging using objectively defined pet parameters to test for statistically significant changes before, during, and after external-beam radiation therapy (ebrt) and to identify the time points at which the changes occur. METHODS: The study enrolled 11 patients with intermediate-risk prostate cancer treated with ebrt, who were followed for up to 12 months after ebrt. The [(11)C]-choline pet scans were performed before treatment (baseline); at weeks 4 and 8 of ebrt; and at 1, 2, 3, 6, and 12 months after ebrt. RESULTS: Analysis of [(11)C]-choline uptake in prostate tissue before treatment resulted in a maximum standardized uptake value (suvmax) of 4.0 ± 0.4 (n = 11) at 40 minutes after injection. During week 8 of ebrt, the suvmax declined to 2.9 ± 0.1 (n = 10, p < 0.05). At 2 and 12 months after ebrt, suvmax values were 2.3 ± 0.3 (n = 10, p < 0.01) and 2.2 ± 0.2 (n = 11, p < 0.001) respectively, indicating that, after ebrt, maximum radiotracer uptake in the prostate was significantly reduced. Similar effects were observed when analyzing the tumour:muscle ratio (tmr). The tmr declined from 7.4 ± 0.6 (n = 11) before ebrt to 6.1 ± 0.4 (n = 11, nonsignificant) during week 8 of ebrt, to 5.6 ± 0.03 (n = 11, p < 0.05) at 2 months after ebrt, and to 4.4 ± 0.4 (n = 11, p < 0.001) at 12 months after ebrt. CONCLUSIONS: Our study demonstrated that intraprostatic [(11)C]-choline uptake in the 11 analyzed prostate cancer patients significantly declined during and after ebrt. The pet parameters SUVmax and tmr also declined significantly. These effects can be detected during radiation therapy and up to 1 year after therapy. The prognostic value of these early and statistically significant changes in intraprostatic [(11)C]-choline pet avidity during and after ebrt are not yet established. Future studies are indicated to correlate changes in [(11)C]-choline uptake parameters with long-term biochemical recurrence to further evaluate [(11)C]-choline pet changes as a possible, but currently unproven, biomarker of response.

4.
Manag Int Rev ; 63(1): 57-90, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36345511

RESUMO

Drawing on institutional theory, this study investigates how institutional pressure can affect digital platform risk. Specifically, it examines whether two types of institutional pressure - domestic market e-commerce policy uncertainty and foreign market e-commerce policy uncertainty - affect the perceived digital platform risk for international new ventures (INVs) and its relationship with their scope of internationalization. The recent crisis caused by the Covid-19 pandemic has further impacted this new phenomenon, thus we examine its effects on the relationships between/among domestic and foreign market e-commerce policy uncertainties, digital platform risk, and the internationalization scope of INVs. We conduct four waves of a survey to test the Covid-19 effects as well as to minimize common method bias, analyzing the final sample of 394 responses from 260 Chinese INVs using structural equation modeling. The results show that domestic and foreign market e-commerce policy uncertainties positively affect the digital platform risk for INVs, with foreign market e-commerce policy uncertainty having a stronger positive impact. Moreover, we find that the Covid-19 pandemic interacts asymmetrically with the relationship between domestic vs. foreign market e-commerce policy uncertainty and the digital platform risk for INVs. In addition, the pandemic strengthens the negative relationship between digital platform risk and the internationalization scope of INVs. This research broadens and strengthens our understanding of e-commerce policy and international business in the context of INVs' internationalization.

5.
Clin Oncol (R Coll Radiol) ; 33(1): 30-39, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711920

RESUMO

AIMS: Skin toxicity is a common adverse effect of breast radiotherapy. We investigated whether inverse-planned intensity-modulated radiotherapy (IMRT) would reduce the incidence of skin toxicity compared with forward field-in-field breast IMRT (FiF-IMRT) in early stage breast cancer. MATERIALS AND METHODS: This phase III randomised controlled trial compared whole-breast irradiation with either FiF-IMRT or helical tomotherapy IMRT (HT-IMRT), with skin toxicity as the primary end point. Patients received 50 Gy in 25 fractions and were assessed to compare skin toxicity between treatment arms. RESULTS: In total, 177 patients were available for assessment and the median follow-up was 73.1 months. Inverse IMRT achieved more homogeneous coverage than FiF-IMRT; erythema and moist desquamation were higher with FiF-IMRT compared with HT-IMRT (61% versus 34%; P < 0.001; 33% versus 11%; P < 0.001, respectively). Multivariate analysis showed large breast volume, FiF-IMRT and chemotherapy were independent factors associated with worse acute toxicity. There was no difference between treatment arms in the incidence of late toxicities. The 5-year recurrence-free survival was 96.3% for both FiF-IMRT and HT-IMRT and the 5-year overall survival was 96.3% for FiF-IMRT and 97.4% for HT-IMRT. CONCLUSIONS: Our study showed significant reduction in acute skin toxicity using HT-IMRT compared with FiF-IMRT, without significant reduction in late skin toxicities. On the basis of these findings, inverse-planned IMRT could be used in routine practice for whole-breast irradiation with careful plan optimisation to achieve the required dose constraints for organs at risk.


Assuntos
Neoplasias da Mama , Efeitos Adversos de Longa Duração , Radiodermite , Radioterapia de Intensidade Modulada , Pele , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Intervalo Livre de Doença , Feminino , Humanos , Efeitos Adversos de Longa Duração/diagnóstico , Efeitos Adversos de Longa Duração/etiologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radiodermite/diagnóstico , Radiodermite/etiologia , Radiodermite/prevenção & controle , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Pele/patologia , Pele/efeitos da radiação
6.
Braz J Biol ; 80(1): 115-121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31291401

RESUMO

According to the Food and Agriculture Organization (FAO), roughly one-third of the total food produced is lost globally. The major cause of this wastage is the perishability of fruits and vegetables. Therefore, researchers have endeavored to develop an effective preservation technique. Our study explored the potential application of spider silk as an odourless and edible preservative coating for fruits. The spider silk was collected from spiders reared in the laboratory, following by degumming and dissolution to formulate the silk solution. For this study, apricots were selected as the model fruit. The apricots were dip coated with the formulated silk solution and allowed to dry. In order to enhance the beta sheet content of the silk coating, the fruits were exposed to water annealing for varying intervals of time under vacuum condition. The effect of silk coating and water annealing time period on preservation of fruits was then evaluated morphologically and gravimetrically. The results showed that the fruits, which were used as control, exhibited a greater degree of water loss and suffered from fungal attack. In contrast, the silk coated fruits showed less water loss and were protected from fungal attack. Therefore, the study provides compelling evidence regarding the application of spider silk as a preservative coating.


Assuntos
Prunus armeniaca , Aranhas , Frutas , Seda , Verduras , Água
7.
Phys Med Biol ; 53(13): 3579-93, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18560047

RESUMO

The aim of this study is to develop a magnetic resonance imaging (MRI)-based treatment planning procedure for intracranial lesions. The method relies on (a) distortion correction of raw magnetic resonance (MR) images by using an adaptive thresholding and iterative technique, (b) autosegmentation of head structures relevant to dosimetric calculations (scalp, bone and brain) using an atlas-based software and (c) conversion of MR images into computed tomography (CT)-like images by assigning bulk CT values to organ contours and dose calculations performed in Eclipse (Philips Medical Systems). Standard CT + MRI-based and MRI-only plans were compared by means of isodose distributions, dose volume histograms and several dosimetric parameters. The plans were also ranked by using a tumor control probability (TCP)-based technique for heterogeneous irradiation, which is independent of radiobiological parameters. For our 3 T Intera MRI scanner (Philips Medical Systems), we determined that the total maximum image distortion corresponding to a typical brain study was about 4 mm. The CT + MRI and MRI-only plans were found to be in good agreement for all patients investigated. Following our clinical criteria, the TCP-based ranking tool shows no significant difference between the two types of plans. This indicates that the proposed MRI-based treatment planning procedure is suitable for the radiotherapy of intracranial lesions.


Assuntos
Encefalopatias/radioterapia , Cabeça/efeitos da radiação , Imageamento por Ressonância Magnética/métodos , Radiometria/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Encefalopatias/patologia , Cabeça/patologia , Humanos , Dosagem Radioterapêutica , Resultado do Tratamento
8.
Braz. j. biol ; 80(1): 115-121, Feb. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1089286

RESUMO

Abstract According to the Food and Agriculture Organization (FAO), roughly one-third of the total food produced is lost globally. The major cause of this wastage is the perishability of fruits and vegetables. Therefore, researchers have endeavored to develop an effective preservation technique. Our study explored the potential application of spider silk as an odourless and edible preservative coating for fruits. The spider silk was collected from spiders reared in the laboratory, following by degumming and dissolution to formulate the silk solution. For this study, apricots were selected as the model fruit. The apricots were dip coated with the formulated silk solution and allowed to dry. In order to enhance the beta sheet content of the silk coating, the fruits were exposed to water annealing for varying intervals of time under vacuum condition. The effect of silk coating and water annealing time period on preservation of fruits was then evaluated morphologically and gravimetrically. The results showed that the fruits, which were used as control, exhibited a greater degree of water loss and suffered from fungal attack. In contrast, the silk coated fruits showed less water loss and were protected from fungal attack. Therefore, the study provides compelling evidence regarding the application of spider silk as a preservative coating.


Resumo Segundo a Organização para Alimentação e Agricultura (FAO), cerca de um terço do total de alimentos produzidos é perdido globalmente. A principal causa deste desperdício é a perecibilidade das frutas e legumes. Portanto, os pesquisadores têm se esforçado para desenvolver uma técnica de preservação eficaz. Nosso estudo explorou a potencial aplicação de seda de aranha como um revestimento conservante inodoro e comestível para frutas. A seda da aranha foi coletada de aranhas criadas em laboratório, seguindo-se a degomagem e dissolução para formular a solução de seda. Para este estudo, os damascos foram selecionados como fruto modelo. Os damascos foram revestidos por imersão com a solução de seda formulada e deixados secar. A fim de aumentar o teor de folhas beta do revestimento de seda, os frutos foram expostos a recozimento de água durante vários intervalos de tempo sob condições de vácuo. O efeito do tempo de recobrimento de seda e recozimento de água na preservação de frutos foi então avaliado morfologicamente e gravimetricamente. Os resultados mostraram que os frutos, utilizados como controle, apresentaram maior grau de perda de água e sofreram ataque fúngico. Em contraste, os frutos revestidos de seda mostraram menos perda de água e foram protegidos contra ataques fúngicos. Portanto, o estudo fornece evidências convincentes sobre a aplicação de seda de aranha como um revestimento conservante.


Assuntos
Aranhas , Prunus armeniaca , Verduras , Água , Seda , Frutas
9.
Arch Pathol Lab Med ; 110(6): 553-5, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3010899

RESUMO

We describe a 78-year-old man with a diffuse large-cell lymphoma that was limited to the liver and was associated with micronodular cirrhosis and Kaposi's sarcoma that involved abdominal lymph nodes and gastric mucosa. The serum of the patient reacted positively to a test for human T-cell lymphotropic virus type III antibodies. We discuss the clinical and autopsy findings for this unusual patient, the criteria for the diagnosis of primary lymphoma of the liver, and its occurrence in patients with the acquired immunodeficiency syndrome.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Neoplasias Hepáticas/etiologia , Linfoma/etiologia , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/patologia , Idoso , Anticorpos Antivirais/análise , Medula Óssea/patologia , Deltaretrovirus/imunologia , Anticorpos Anti-HIV , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Linfonodos/patologia , Linfoma/patologia , Masculino , Sarcoma de Kaposi/etiologia , Sarcoma de Kaposi/patologia
10.
Arch Gerontol Geriatr ; 14(2): 117-22, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-15374396

RESUMO

Pathological and clinical findings of all consecutive autopsies performed at The Jewish Home and Hospital for Aged from 4/1/85 to 12/31/86 were reviewed to determine the frequency and clinical significance of pulmonary embolism as a cause of death in the nursing home. The autopsies were performed by a single pathologist and a diagnosis of pulmonary embolism (PE) was based on microscopic confirmation of macroscopic findings. All charts during this time period were reviewed for classic signs and symptoms of PE, presence of risk factors associated with PE, ambulatory status and rapidity of death. The autopsy rate during this period was 25.6%. Of 41 autopsies reviewed (31 females and 10 males) 14 cases of pulmonary embolism were found representing a prevalence of 34.1%. All occurred in females. Pulmonary infarction was present in four cases. Massive PE (interrupting blood flow to both lungs) and major PE (interrupting flow to one entire lung) made up 11 of the cases (26.8% of all autopsies). Classic symptoms were not more frequent premortem in those with PE than those without PE. The presence of risk factors, or rapid death, or bedbound state did not predict the presence of PE. In none of the cases was the diagnosis established premortem. Elderly female residents of chronic care facilities appear to be at special risk of death from pulmonary embolism. Clinical findings are not of a diagnostic nature.

11.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467292

RESUMO

Abstract According to the Food and Agriculture Organization (FAO), roughly one-third of the total food produced is lost globally. The major cause of this wastage is the perishability of fruits and vegetables. Therefore, researchers have endeavored to develop an effective preservation technique. Our study explored the potential application of spider silk as an odourless and edible preservative coating for fruits. The spider silk was collected from spiders reared in the laboratory, following by degumming and dissolution to formulate the silk solution. For this study, apricots were selected as the model fruit. The apricots were dip coated with the formulated silk solution and allowed to dry. In order to enhance the beta sheet content of the silk coating, the fruits were exposed to water annealing for varying intervals of time under vacuum condition. The effect of silk coating and water annealing time period on preservation of fruits was then evaluated morphologically and gravimetrically. The results showed that the fruits, which were used as control, exhibited a greater degree of water loss and suffered from fungal attack. In contrast, the silk coated fruits showed less water loss and were protected from fungal attack. Therefore, the study provides compelling evidence regarding the application of spider silk as a preservative coating.


Resumo Segundo a Organização para Alimentação e Agricultura (FAO), cerca de um terço do total de alimentos produzidos é perdido globalmente. A principal causa deste desperdício é a perecibilidade das frutas e legumes. Portanto, os pesquisadores têm se esforçado para desenvolver uma técnica de preservação eficaz. Nosso estudo explorou a potencial aplicação de seda de aranha como um revestimento conservante inodoro e comestível para frutas. A seda da aranha foi coletada de aranhas criadas em laboratório, seguindo-se a degomagem e dissolução para formular a solução de seda. Para este estudo, os damascos foram selecionados como fruto modelo. Os damascos foram revestidos por imersão com a solução de seda formulada e deixados secar. A fim de aumentar o teor de folhas beta do revestimento de seda, os frutos foram expostos a recozimento de água durante vários intervalos de tempo sob condições de vácuo. O efeito do tempo de recobrimento de seda e recozimento de água na preservação de frutos foi então avaliado morfologicamente e gravimetricamente. Os resultados mostraram que os frutos, utilizados como controle, apresentaram maior grau de perda de água e sofreram ataque fúngico. Em contraste, os frutos revestidos de seda mostraram menos perda de água e foram protegidos contra ataques fúngicos. Portanto, o estudo fornece evidências convincentes sobre a aplicação de seda de aranha como um revestimento conservante.

12.
Curr Oncol ; 19(3): e201-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22670110

RESUMO

PURPOSE: We examined the impact of hypofractionated radiation therapy and androgen suppression therapy (AST) on quality of life (QOL) in high-risk prostate cancer patients. METHODS: Between March 2005 and March 2007, 60 patients with high-risk prostate cancer were enrolled in a prospective phase ii study. All patients received 68 Gy (2.72 Gy per fraction) to the prostate gland and 45 Gy (1.8 Gy per fraction) to the pelvic lymph nodes in 25 fractions over 5 weeks. Of the 60 patients, 58 received ast. The University of California-Los Angeles Prostate Cancer Index questionnaire was used to prospectively measure QOL at baseline (month 0) and at 1, 6, 12, 18, 24, 30, and 36 months after radiation treatment. The generalized estimating equation approach was used to compare the QOL scores at 1, 6, 12, 18, 24, 30, and 36 months with those at baseline. RESULTS: We observed a significant decrease in QOL items related to bowel and sexual function. Several QOL items related to bowel function were significantly adversely affected at both 1 and 6 months, with improvement toward 6 months. Although decreased QOL scores persisted beyond the 6-month mark, they began to re-approach baseline at the 18- to 24-month mark. Most sexual function items were significantly adversely affected at both 1 and 6 months, but the effects were not considered to be a problem by most patients. A complete return to baseline was not observed for either bowel or sexual function. Urinary function items remained largely unaffected, with overall urinary function being the only item adversely affected at 6 months, but not at 1 month. Urinary function returned to baseline and remained unimpaired from 18 months onwards. CONCLUSIONS: In our study population, who received hypofractionated radiation delivered using dynamic intensity-modulated radiotherapy with inclusion of the pelvic lymph nodes, and 2-3 years of ast prescription, QOL with respect to bowel and sexual function was significantly affected; QOL with respect to urinary function was largely unaffected. Our results are comparable to those in other published studies.

13.
Hum Pathol ; 16(8): 860-1, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4018788
18.
J Med Imaging Radiat Oncol ; 52(1): 95-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18373835

RESUMO

Low-grade chondrosarcomas are the least aggressive and may recur locally with rare metastatic potential. We report a case of low-grade chondrosarcoma of bone, which metastasized to the lungs.


Assuntos
Neoplasias Ósseas/patologia , Condrossarcoma/patologia , Neoplasias Pulmonares/secundário , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/cirurgia , Condrossarcoma/diagnóstico , Condrossarcoma/cirurgia , Seguimentos , Humanos , Úmero/cirurgia , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
19.
Am J Forensic Med Pathol ; 6(4): 293-5, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4072982

RESUMO

Recently, awareness of the importance of forensic pathology and related sciences in the United States has grown. At our medical center, we developed a concise and systematic program on this subject and offered it as an elective in pathology to level II medical students. The course was very successful and rated highly by the medical students.


Assuntos
Educação Médica , Medicina Legal/educação , Patologia Clínica/educação , Adolescente , Adulto , Humanos
20.
Am J Forensic Med Pathol ; 9(2): 163-5, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3381798

RESUMO

Occult foreign body aspiration is an uncommon but serious occurrence in the elderly population. A case is presented in which the foreign body, a nut, was uncovered only at autopsy.


Assuntos
Brônquios , Corpos Estranhos/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Autopsia , Brônquios/patologia , Feminino , Humanos , Nozes
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