Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Med Dosim ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38735781

RESUMO

Recently, carbon fiber (CF) has prevailed as the primary material used in radiotherapy couchtops. Modern couchtops incorporate the CF sandwich design, in which 2 thin CF plates sandwich an air-equivalent polymeric foam. Developments in radiotherapy necessitate irradiation from posterior angles through the couchtop. However, the presence of the couchtop needs proper modeling in the treatment planning system (TPS) due to attenuation; otherwise, the tumor dose is reduced. In the current study, an effort was made with the intent of finding the optimum electron density (ED) values for Elekta's iBEAM Evo couchtop components (CF and Foam Core (FC)) for its proper modeling in Monaco TPS. Also, the attenuation of the beam due to the couchtop's presence was investigated. A cylindrical phantom with an ionization chamber positioned at the isocenter was utilized for the measurements. The phantom was placed centrally on the iBEAM Evo couchtop and was irradiated with an Elekta Infinity linear accelerator's 6, 10, and 15 MV photon beams. The gantry angle was set at 0o and from 120o to 180o with an increment of 10o. The same procedure was designed and followed in Monaco TPS. Measured and calculated dose values were compared by calculating percentage deviation (PD). Attenuation has also been calculated using the measurements of the experimental setup and the Monaco calculations. The values of ED that provided the optimum agreement between measured and Monaco-calculated dose values while minimizing PD were 0.55 g/cm3 for CF, and 0.1 g/cm3 for FC. The maximum values of PD for the beams of 6, 10, and 15 MV were -0.62%, +1,78%, and +2.35%, respectively, for a 5 × 5 cm2 field size. Furthermore, Monaco predicted attenuation from 1.83% to 6.26% (calculated values), while from the measurements, an attenuation from 1.44% to 5.75% (measured values) regarding the posterior angles was found. Thus, good agreement was verified between the TPS calculations and experimental measurements. Elekta's iBEAM Evo couchtop modeling was successfully validated in Monaco TPS. The couchtop's presence alters the patient's dose regarding irradiation from the posterior angles. Due to the attenuation of the beam, proper incorporation, modeling, and validation of the couchtop are necessary to improve the radiotherapy outcome and ensure that each patient receives the optimal treatment.

2.
Cancers (Basel) ; 16(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38672636

RESUMO

Cancer is a life-threatening disease and one of the leading causes of death worldwide. Despite significant advancements in therapeutic options, most available anti-cancer agents have limited efficacy. In this context, natural compounds with diverse chemical structures have been investigated for their multimodal anti-cancer properties. Curcumin is a polyphenol isolated from the rhizomes of Curcuma longa and has been widely studied for its anti-inflammatory, anti-oxidant, and anti-cancer effects. Curcumin acts on the regulation of different aspects of cancer development, including initiation, metastasis, angiogenesis, and progression. The phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) pathway is a key target in cancer therapy, since it is implicated in initiation, proliferation, and cancer cell survival. Curcumin has been found to inhibit the PI3K/Akt pathway in tumor cells, primarily via the regulation of different key mediators, including growth factors, protein kinases, and cytokines. This review presents the therapeutic potential of curcumin in different malignancies, such as glioblastoma, prostate and breast cancer, and head and neck cancers, through the targeting of the PI3K/Akt signaling pathway.

3.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396771

RESUMO

To date, many potent compounds have been found which are derived from plants and herbs and possess anticancer properties due to their antioxidant effects. 9″-Lithospermic acid methyl ester is an effective natural compound derived from the Thymus thracicus Velen. It has been proven that this compound has substantial properties in different diseases, but its effects in cancer have not been thoroughly evaluated. The aim of this work was to study the effects of 9″-Lithospermic acid methyl ester (9″-methyl lithospermate) in U87 and T98 glioblastoma cell lines. Its effects on cellular viability were assessed via Trypan Blue and Crystal Violet stains, the cell cycle analysis through flow cytometry, and cell migration by employing the scratch wound healing assay. The results demonstrated that 9″-methyl lithospermate was able to inhibit cellular proliferation, induce cellular death, and inhibit cell migration. Furthermore, these results were intensified by the addition of temozolomide, the most prominent chemotherapeutic drug in glioblastoma tumors. Further studies are needed to reproduce these findings in animal models and investigate if 9″-lithospermic acid methyl ester represents a potential new therapeutic addition for gliomas.


Assuntos
Antineoplásicos , Benzofuranos , Neoplasias Encefálicas , Depsídeos , Glioblastoma , Animais , Glioblastoma/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Temozolomida/farmacologia , Benzofuranos/farmacologia , Proliferação de Células , Linhagem Celular Tumoral , Apoptose , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia
4.
Clin Neurol Neurosurg ; 211: 107038, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34823153

RESUMO

OBJECTIVES: There is limited data on the direct clinical comparison between short and long fusion following surgery for lumbar spinal stenosis. The hypothesis that regardless their baseline characteristics and morbidity, clinical outcome is similar in patients with lumbar stenosis treated with decompression plus posterior instrumented fusion in one or two versus three to five levels was tested. METHODS: Subjects were divided into Group A and Group B corresponding to stenotic pathology and instrumented fusion in one or two levels and three to five levels, respectively. Primary outcome measures at one year were the change in SF-36 physical component (PCS) and Oswestry Disability Index (ODI). Secondary outcome measures included the EuroQol-5D (EQ-5D), the Visual Analog Scale (VAS), the mental component (MCS) of SF-36 scale and the Zung Self-Rating Depression Scale. RESULTS: Seventy seven (77) patients were included (Group A, n = 42; Group B, n = 35). Patients in Group B were older, surgery lasted longer and intraoperative blood loss was greater than patients in Group A (p < 0.05). A significant clinical improvement was noted in both Groups on all scales (p < 0.01). Clinical outcome at one year was equally favorable in both Groups (p > 0.05). The evaluation of depression for Group A showed a significant improvement at one year (p = 0.02) compared to the preoperative status. CONCLUSIONS: Older individuals are more likely to have multilevel stenosis and more co-morbidities and they were associated with longer instrumentation. However, complications are similar and clinical outcome is equally favorable compared to short instrumented fusion for fewer levels of disease.


Assuntos
Descompressão Cirúrgica , Vértebras Lombares , Fusão Vertebral/instrumentação , Estenose Espinal/cirurgia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Resultado do Tratamento
5.
Cureus ; 13(8): e17365, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34567904

RESUMO

Brain abscesses caused by sinusitis are rare in the antibiotic era. The purpose of the current manuscript was to report a rare case of a brain abscess located mainly in the frontal lobe after sinusitis, which was initially thought to be meningitis or encephalitis. A 39-year-old man was transferred to our hospital from another neighbouring hospital with tonic-clonic seizures, severe headache, and purulent nasal secretions. For one week, he was taking antibiotics for sinusitis. The computed tomography indicated lesions in the right sinuses but not in the parenchymal brain and thus antibiotics along with antiepileptic drugs were given. However, due to the deterioration of symptoms, magnetic resonance imaging was executed, which revealed an abscess in the frontal lobe. Afterward, an anterior ethmoidectomy and middle maxillary antrostomy were performed in order to drain the purulent content from the right sinuses. Ten days later, the patient presented disorientation and thus an open craniotomy for successful removal of the parenchymal abscess was performed. One month later, the patient was discharged with mild irritability, which was eliminated gradually over the next two months. Conclusively, brain abscesses can be caused by local spread from an infection of the paranasal sinus. The contribution of imaging modality is very significant not only for the early diagnosis but also for the therapeutic management of such cases. Frequently antibiotic treatment is insufficient and surgery may be required.

6.
BMC Med Res Methodol ; 8: 66, 2008 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19239725

RESUMO

BACKGROUND: Database systems have been developed to store data from large medical trials and survey studies. However, a reliable data storage system does not guarantee data entering reliability.We aimed to evaluate if double-blind control of the data manager might have any effect on data-reliability. Our secondary aim was to assess the influence of the inserting position in the insertion-sheet on data-entry accuracy and the effectiveness of electronic controls in identifying data-entering mistakes. METHODS: A cross-sectional survey and single data-manager data entry.Data from PACMeR_02 survey, which had been conducted within a framework of the SESy-Europe project (PACMeR_01.4), were used as substrate for this study. We analyzed the electronic storage of 6,446 medical charts. We structured data insertion in four sequential phases. After each phase, the data stored in the database were tested in order to detect unreliable entries through both computerized and manual random control. Control was provided in a double blind fashion. RESULTS: Double-blind control of the data manager didn't improve data entry reliability. Entries near the end of the insertion sheet were correlated with a larger number of mistakes. Data entry monitoring by electronic-control was statistically more effective than hand-searching of randomly selected medical records. CONCLUSION: Double-blind control of the data manager should be considered an avoidable cost. Electronic-control for monitoring of data-entry reliability is suggested.


Assuntos
Custos e Análise de Custo , Método Duplo-Cego , Processamento Eletrônico de Dados , Sistemas de Informação/economia , Sistemas Computadorizados de Registros Médicos/economia , Sistemas de Apoio a Decisões Clínicas , Humanos , Prontuários Médicos/economia , Prontuários Médicos/normas , Sistemas Computadorizados de Registros Médicos/normas , Reprodutibilidade dos Testes , Recursos Humanos
7.
Hell J Nucl Med ; 10(3): 205-8, 2007.
Artigo em Grego Moderno | MEDLINE | ID: mdl-18084668

RESUMO

Morphologic characterization of brain tumors by magnetic resonance imaging and computed tomography is well established. However, functional metabolic imaging by single-photon emission tomography (SPET) and positron emission tomography are also increasingly important imaging tools for noninvasive assessment of brain tumors. Brain SPET is useful in the differentiation of tumor recurrence from radiation necrosis, in the non-invasive assessment of gliomas and meningiomas aggressiveness, in differentiating neoplastic from non neoplastic intracerebral haemorrhage, in monitoring therapy response and in the evaluation of other types of brain tumors. Our own experience is presented supporting the above.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Glioma/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Necrose/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Neoplasias Encefálicas/patologia , Hemorragia Cerebral/patologia , Diagnóstico Diferencial , Glioma/patologia , Humanos , Meningioma/patologia , Necrose/patologia , Recidiva
8.
Cent Eur J Public Health ; 15(2): 71-3, 2007 06.
Artigo em Inglês | MEDLINE | ID: mdl-17645221

RESUMO

Skin tumors are the most frequent malignancies in the white population worldwide and have reached the proportion of an epidemic disease. Since non-melanocytic skin cancers can be cured when timely detected, given that still malignant melanoma may have good prognosis if early diagnosed, and considering the key role of primary care in cancer screening advising and implementation, the international PACMeR study group (trial_01.3) adjourned SESy_Europe database in a version comprehensive of skin-malignancies screening indexing. The novel database provides standardized pre-codified translations of 2,331 parameters in eight languages (English, French, German, Greek, Italian, Romanian, Spanish and Turkish) and records the time elapsed from last skin examination, cause and frequency of skins examinations and stratifies skin cancer risk patterns by a systematic registering of risk factors. A comprehensive indexing of skin cancer screening practices among European countries may in fact turn helpful in programming future health policy and tailoring interventions.


Assuntos
Bases de Dados como Assunto , Programas de Rastreamento/organização & administração , Neoplasias Cutâneas/diagnóstico , Europa (Continente) , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA