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1.
PLoS One ; 19(7): e0306857, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39037987

RESUMO

OBJECTIVE: Using pediatric anthropomorphic phantoms (APs), we aimed to determine the scanning tube voltage/current combinations that could achieve optimal image quality and avoid excessive radiation exposure in pediatric patients. MATERIALS AND METHODS: A 64-slice scanner was used to scan a standard test phantom to determine the volume CT dose indices (CTDIvol), and three pediatric anthropomorphic phantoms (APs) with highly accurate anatomy and tissue-equivalent materials were studied. These specialized APs represented the average 1-year-old, 5-year-old, and 10-year-old children, respectively. The physical phantoms were constructed with brain tissue-equivalent materials having a density of ρ = 1.07 g/cm3, comprising 22 numbered 2.54-cm-thick sections for the 1-year-old, 26 sections for the 5-year-old, and 32 sections for the 10-year-old. They were scanned to acquire brain CT images and determine the standard deviations (SDs), effective doses (EDs), and contrast-to noise ratios (CNRs). The APs were scanned by 21 combinations of tube voltages/currents (80, 100, or 120 kVp/10, 40, 80, 120, 150, 200, or 250 mA) and rotation time/pitch settings of 1 s/0.984:1. RESULTS: The optimal tube voltage/current combinations yielding optimal image quality were 80 kVp/80 mA for the 1-year-old AP; 80 kVp/120 mA for the 5-year-old AP; and 80 kVp/150 mA for the 10-year-old AP. Because these scanning tube voltages/currents yielded SDs, respectively, of 12.81, 13.09, and 12.26 HU, along with small EDs of 0.31, 0.34, and 0.31 mSv, these parameters and the induced values were expediently defined as optimal. CONCLUSIONS: The optimal tube voltages/currents that yielded optimal brain image quality, SDs, CNRs, and EDs herein are novel and essentially important. Clinical translation of these optimal values may allow CT diagnosis with low radiation doses to children's heads.


Assuntos
Encéfalo , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada por Raios X , Humanos , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Tomografia Computadorizada por Raios X/métodos , Lactente , Masculino
2.
Artigo em Inglês | MEDLINE | ID: mdl-39009321

RESUMO

Locally recurrent nasopharyngeal carcinoma (NPC) presents substantial challenges in clinical management. Although postoperative re-irradiation (re-RT) has been acknowledged as a potential treatment option, standardized guidelines and consensus regarding the use of re-RT in this context are lacking. This article provides a comprehensive review and summary of international recommendations on postoperative management for potentially resectable locally recurrent NPC, with a special focus on postoperative re-RT. A thorough search was conducted to identify relevant studies on postoperative re-RT for locally recurrent NPC. Controversial issues, including resectability criteria, margin assessment, indications for postoperative re-RT, and the optimal dose and method of re-RT, were addressed through a Delphi consensus process. The consensus recommendations emphasize the need for a clearer and broader definition of resectability, highlighting the importance of achieving clear surgical margins, preferably through an en bloc approach with frozen section margin assessment. Furthermore, these guidelines suggest considering re-RT for patients with positive or close margins. Optimal postoperative re-RT doses typically range around 60 Gy, and hyperfractionation has shown promise in reducing toxicity. These guidelines aim to assist clinicians in making evidence-based decisions and improving patient outcomes in the management of potentially resectable locally recurrent NPC. By addressing key areas of controversy and providing recommendations on resectability, margin assessment, and re-RT parameters, these guidelines serve as a valuable resource for clinical experts involved in the treatment of locally recurrent NPC.

3.
PLoS One ; 16(11): e0259772, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34767600

RESUMO

Exposure to ionizing radiation can cause cancer, especially in children. In computed tomography (CT), a trade-off exists between the radiation dose and image quality. Few studies have investigated the effect of dose reduction on image quality in pediatric neck CT. We aimed to assess the effect of peak kilovoltage on the radiation dose and image quality in pediatric neck multidetector-row CT. Measurements were made using three phantoms representative of children aged 1, 5, and 10 years, with tube voltages of 80, 100, and 120 kilovoltage peak (kVp); tube current of 10, 40, 80, 120, 150, 200, and 250 mA; and exposure time = 0.5 s (pitch, 0.984:1). Radiation dose estimates were derived from the dose-length product with a 64-multidetector-row CT scanner. Images obtained from the control protocol (120 kVp) were compared with the 80- and 100-kVp protocols. The effective dose (ED) was determined for each protocol and compared with the 120-kVp protocol. Quantitative analysis entailed noise measurements by recording the standard deviation of attenuation for a circular 1-cm2 region of interest placed on homogeneous soft tissue structures in the phantom. The mean noise of the various kVp protocols was compared using the unpaired Student t-test. Reduction of ED was 37.58% and 68.58% for neck CT with 100 kVp and 80 kVp, respectively. The image noise level increased with the decrease in peak kilovoltage. Noise values were higher at 80 kVp at all neck levels, but did not increase at 100 kVp, compared to 120 kVp in the three phantoms. The measured noise difference was the greatest at 80 kVp (absolute increases<2.5 HU). The subjective image quality did not differ among the protocols. Thus, reducing voltage from 120 to 80 kVp for neck CT may achieve ED reduction of 68.58%, without compromising image quality.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Pescoço/diagnóstico por imagem , Doses de Radiação , Radiação Ionizante , Criança , Pré-Escolar , Humanos , Lactente
4.
Laryngoscope ; 131(7): 1548-1556, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33571390

RESUMO

OBJECTIVE/HYPOTHESIS: To investigate the endovascular intervention or extracranial/intracranial (EC/IC) vascular bypass in the management of patients with head and neck cancer-related carotid blowout syndrome (CBS). STUDY DESIGN: Retrospective case series. METHODS: Retrospective analysis of clinical data of patients with head and neck cancer-related CBS treated by endovascular intervention and/or EC/IC vascular bypass, analysis of its bleeding control, neurological complications, and survival results. RESULTS: Thrity-seven patients were included. Twenty-five were associated with external carotid artery (ECA); twelve were associated with internal or common carotid artery (ICA/CCA). All patients with ECA hemorrhage were treated with endovascular embolization. Of the 12 patients with ICA/CCA hemorrhage, 9 underwent EC/IC bypass, 1 underwent endovascular embolization, and 3 underwent endovascular stenting. For patients with ECA-related CBS, the median survival was 6 months, and the 90-day, 1-year, and 2-year survival rates were 67.1%, 44.7%, and 33.6%, respectively; the estimated rebleeding risk at 1-month, 6-month, and 2-year was 7.1%, 20.0%, and 31.6%, respectively. For patients with ICA/CCA-related CBS, the median survival was 22.5 months, and the 90-day, 1-year, and 2-year survival rates were 92.3%, 71.8%, and 41.0%, respectively; the estimated rebleeding risk at 1 month, 6 months, and 2 years is 7.7%,15.4%, and 15.4%, respectively. ICA/CCA-related CBS patients have significantly longer survival time and lower risk of rebleeding, which may be related to the more use of EC/IC vascular bypass as a definite treatment. CONCLUSIONS: For patients with ICA/CCA-related CBS, if there is more stable hemodynamics, longer expected survival, EC/IC vascular bypass is preferred. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:1548-1556, 2021.


Assuntos
Doenças das Artérias Carótidas/cirurgia , Revascularização Cerebral/métodos , Procedimentos Endovasculares/métodos , Neoplasias de Cabeça e Pescoço/complicações , Hemorragia/cirurgia , Adulto , Idoso , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/mortalidade , Artéria Carótida Externa/cirurgia , Artéria Carótida Interna/cirurgia , Revascularização Cerebral/instrumentação , Revascularização Cerebral/estatística & dados numéricos , Embolização Terapêutica/estatística & dados numéricos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/estatística & dados numéricos , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/mortalidade , Hemorragia/etiologia , Hemorragia/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Medição de Risco/estatística & dados numéricos , Ruptura Espontânea/etiologia , Ruptura Espontânea/mortalidade , Ruptura Espontânea/cirurgia , Prevenção Secundária/instrumentação , Prevenção Secundária/métodos , Prevenção Secundária/estatística & dados numéricos , Stents , Taxa de Sobrevida , Resultado do Tratamento
5.
Cell Transplant ; 27(3): 456-470, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29756519

RESUMO

Parkinson's disease (PD) causes motor dysfunction and dopaminergic cell death. Drug treatments can effectively reduce symptoms but often cause unwanted side effects. Stem cell therapies using cell replacement or indirect beneficial secretomes have recently emerged as potential therapeutic strategies. Although various types of stem cells have been proposed as possible candidates, adipose-derived stem cells (ADSCs) are easily obtainable, more abundant, less ethically disputed, and able to differentiate into multiple cell lineages. However, treatment of PD using adult stem cells is known to be less efficacious than neuron or embryonic stem cell transplantation. Therefore, improved therapies are urgently needed. n-Butylidenephthalide (BP), which is extracted from Angelica sinensis, has been shown to have anti-inflammatory and neuroprotective effects. Indeed, we previously demonstrated that BP treatment of ADSCs enhances the expression of neurogenesis and homing factors such as nuclear receptor related 1 protein, stromal-derived factor 1, and brain-derived neurotrophic factor. In the present study, we examined the ability of BP-pretreated ADSC transplantation to improve PD motor symptoms and protect dopamine neurons in a mouse model of PD. We evaluated the results using neuronal behavior tests such as beam walking, rotarod, and locomotor activity tests. ADSCs with or without BP pretreatment were transplanted into the striatum. Our findings demonstrated that ADSC transplantation improved motor abilities with varied efficacies and that BP stimulation improved the therapeutic effects of transplantation. Dopaminergic cell numbers returned to normal in ADSC-transplanted mice after 22 d. In summary, stimulating ADSCs with BP improved PD recovery efficiency. Thus, our results provide important new strategies to improve stem cell therapies for neurodegenerative diseases in future studies.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Doença de Parkinson/terapia , Anidridos Ftálicos/farmacologia , Adipócitos/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
Auris Nasus Larynx ; 44(4): 458-463, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28188026

RESUMO

OBJECTIVE: To investigate the expression of integrin-linked kinase (ILK) and its relationship with clinicopathological parameters in laryngeal squamous cell carcinoma (LSCC). METHODS: 116 patients who had previously undergone complete resection of tumor for LSCC were studied retrospectively. The level of ILK expression in tumor tissues and adjacent nontumor tissues were determined by immunohistochemistry. RESULTS: Increased expression of ILK was found in 65.5% of cases. The expression of ILK protein was significantly associated with tumor grade (p=0.046), lymph node metastasis (p=0.020), and pTNM stage (p=0.019). Kaplan-Meier survival estimates showed a significant correlation between ILK expression and patient survival rate (log-rank p<0.05). The multivariate survival analysis revealed that N status was statistically significant prognostic factor (p<0.001). Other parameters, such as ILK expression, cannot predict disease prognosis separately. CONCLUSION: Increased expression of integrin-linked kinase is associated with lymph node metastases and patient survival rate in laryngeal squamous cell carcinoma. However, it does not appear to be an independent prognostic predictor in LSCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias Laríngeas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Análise de Sobrevida
7.
Zhong Yao Cai ; 34(8): 1196-9, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22233032

RESUMO

OBJECTIVE: To choose the optimum initial processing methods of Rheum palmatum. METHODS: Fresh crude Rheum palmatum was sliced and dealt with the different drying methods such as sun drying, shady drying, microwave heating and various temperatures drying. The content of the Anthraquinones derivatives, slicing colors and dried rates were used as evaluation indexes. The sliced Rheum palmatum was compared with the traditional processing. RESULTS: Sliced fresh crude Rheum palmatum had the low content of the Anthraquinones derivatives and dry rates, slicing colours had obviously changes. For various drying methods, smoking drying was superior to sun drying, shady drying, microwave heating and various temperatures drying methods. CONCLUSION: Fresh crude Rheum palmatum is not suitable for slicing processing. The best drying method is smoking drying.


Assuntos
Antraquinonas/análise , Dessecação/métodos , Plantas Medicinais/química , Rheum/química , Cromatografia Líquida de Alta Pressão , Micro-Ondas , Raízes de Plantas/química , Plantas Medicinais/crescimento & desenvolvimento , Controle de Qualidade , Reprodutibilidade dos Testes , Rheum/crescimento & desenvolvimento , Rizoma/química , Tecnologia Farmacêutica/métodos
8.
Artigo em Chinês | MEDLINE | ID: mdl-19957656

RESUMO

OBJECTIVE: To investigate the distribution and projective feature of cat olivocochlear neurons. METHODS: Eleven adult cats were divided into two groups randomly. The experimental group of eight cats was injected of 1% cholera toxin B (CTB) to the left cochlea, while injected of 5% fluoro gold (FG) to the right cochlea. The control group of three cats was injected of saline to bilateral cochlea. After a survival time of 7 days, serial frozen sections were cut in the cat brainstem. All the sections were processed by immunofluorescent procedure for CTB and FG, and the labeled olivocochlear neurons were observed by fluorescent microscope. RESULTS: In the experimental group, the mean total of olivocochlear neurons labeled by CTB and FG was 3210 +/- 168, including lateral olivocochlear neurons (LOC, 2298 +/- 120) and medial olivocochlear neurons (MOC, 913 +/- 64). The labeled neurons were divided into three different types according to their feature of projection: neurons which only projected to the ipsilateral cochlea, neurons which only projected to the contralateral cochlea, and double-labeled neurons which projected both to the ipsilateral and contralateral cochlea, but the double-labeled neurons comprised 3.9% and 15.1% in the LOC and MOC system respectively. No labeled neurons were found in the control group. CONCLUSIONS: There are three types of neurons in the cat olivocochlear system. The neurons which projected to the bilateral cochlea may distribute both in the LOC and MOC system.


Assuntos
Vias Auditivas , Núcleo Coclear/anatomia & histologia , Neurônios/fisiologia , Núcleo Olivar/fisiologia , Animais , Biomarcadores , Gatos , Corantes Fluorescentes
9.
Artigo em Chinês | MEDLINE | ID: mdl-20359112

RESUMO

OBJECTIVE: To evaluate the effectiveness of the anterolateral thigh flap in reconstruction for the tissue defects of hypopharyngeal and cervical esophageal tumor resection. METHOD: Retrospective review of two clinical cases who underwent pharyngoesophageal reconstruction with the anterolateral thigh flap after tumor ablation. RESULT: No flap failure, fistula and stricture occurred in two patients. Two patients tolerated a regular diet. An esophageal voice was progressively acquired with the help of speech therapy. With followup for 16 and 41 months two patients were alive without tumor evolution. CONCLUSION: The higher success rate,lower complication, quick recovery, made the anterolateral thigh flap interposition is the ideal choice for pharyngoesophageal reconstruction.


Assuntos
Neoplasias Esofágicas/cirurgia , Neoplasias Hipofaríngeas/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Coxa da Perna/cirurgia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante de Pele , Retalhos Cirúrgicos
10.
Mutat Res ; 562(1-2): 27-38, 2004 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-15279828

RESUMO

The objective of this study was to use the micronuclei from exfoliated buccal mucosal cells to investigate the clastogenic effects of areca quid chewing and cigarette smoking, as well as the interaction between the two. The study population was selected from residents of seven villages recruited for a community-cohort study. A total of 141 subjects were recruited based on the regular consumption of cigarettes and betel quid. Salient personal characteristics were collected from interview using a specially designed questionnaire. Micronuclei were scored on Feulgen/fast green-stained smear preparations of exfoliated cells obtained by scraping the surface of the buccal mucosa. There was no significant interaction between the chewing of betel nut and cigarette smoking. Heavy smoking was positively associated with MN frequency, with areca quid chewing negatively associated. A significant positive trend was demonstrated for the relationship between MN frequency and either daily cigarette consumption or cumulative smoking pack-years. By contrast, negative trends were demonstrated for the analogous relationships with areca quid chewing. These results indicate that heavy smoking, but not areca quid chewing, increases MN formation. These findings suggest that the carcinogenesis of the oral cancers induced by areca quid chewing in Taiwan may be through a pathway other than genotoxicity.


Assuntos
Areca , Micronúcleos com Defeito Cromossômico , Mucosa Bucal/citologia , Nicotiana , Fumar/genética , Adulto , Humanos , Pessoa de Meia-Idade
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