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1.
Cancer Radiother ; 27(5): 398-406, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37482464

RESUMO

PURPOSE: This study aims to perform a comprehensive systematic review of deep learning (DL) models in predicting RT-induced toxicity. MATERIALS AND METHODS: A literature review was performed following the PRISMA guidelines. Systematic searches were performed in PubMed, Scopus, Cochrane and Embase databases from the earliest record up to September 2022. Related studies on deep learning models for radiotherapy toxicity prediction were selected based on predefined PICOS criteria. RESULTS: Fourteen studies of radiotherapy-treated patients on different types of cancer [prostate (n=2), HNC (n=4), liver (n=2), lung (n=4), cervical (n=1), and oesophagus (n=1)] were eligible for inclusion in the systematic review. Information regarding patient characteristics and model development was summarized. Several approaches, such as ensemble learning, data augmentation, and transfer learning, that were utilized by selected studies were discussed. CONCLUSION: Deep learning techniques are able to produce a consistent performance for toxicity prediction. Future research using large and diverse datasets and standardization of the study methodologies are required to improve the consistency of the research output.


Assuntos
Aprendizado Profundo , Neoplasias , Masculino , Humanos
2.
J Colloid Interface Sci ; 600: 187-198, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015511

RESUMO

An investigation on relationship among the physicochemical, optical and dielectric properties of the hydroxyapatite/cornstarch (HA/Cs) composites with the starch proportion of 30, 40, 50, 60, 70, 80 and 90 wt% is presented in this work. The HA/Cs composites have been characterized via FTIR, XRD, DRS and impedance analyzer. This work depicts that the strong interaction is exhibited between the hydroxyapatite nanoparticles and starch as the starch proportion increases. This increment trend results in the higher crystallinity of the HA/Cs composites. The highly crystallized HA/Cs with hydroxyapatite nucleation center presents low optical properties (diffuse reflectance and optical band gap energy). The HA/Cs composite with 80 wt% starch proportion (H2C8) show higher dielectric properties (dielectric constant, loss factor and conductivity) due to the stronger interfacial interaction and close-packed HA/Cs crystalline structure. The relationship among the physicochemical, optical and dielectric properties of the HA/Cs composite is studied in this work for potential of instrumentation design.


Assuntos
Durapatita , Nanopartículas , Fenômenos Físicos , Amido
3.
Int J Biol Macromol ; 166: 1543-1553, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33181217

RESUMO

This paper provides a comprehensive analysis of the dielectric and physicochemical properties of the porous hydroxyapatite/cornstarch (HAp/Cs) composites in a new perspective. The porous composites have been characterized via SEM, FTIR, XRD and dielectric spectroscopy. The dielectric permittivity spectra were obtained in Ku-band (12.4-18.0 GHz) and it was correlated with the physicochemical properties of the porous HAp/Cs. Porous HAp/Cs composites exhibits low ε' and negative ε″, which influenced by the microstructural morphology, interaction between Hap and Cs, as well as crystalline features due to the various proportion of the HAp/Cs. The physicochemical effect of the composites results in the dielectric polarization and energy loss. This phenomenon indicates the presence of the three obvious relaxation responses in the ε' spectrum (13.2-14.0, 15.2-16.0, and 16.6-17.4 GHz) and the negative behaviours in the ε″ spectrum. The relationships between physicochemical and dielectric properties of the porous composite facilitate the development of the non-destructive microwave evaluation test for the porous composite.


Assuntos
Hidroxiapatitas/química , Nanocompostos/química , Amido/análogos & derivados , Micro-Ondas , Nanopartículas/química , Porosidade
4.
Med J Malaysia ; 72(2): 94-99, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28473671

RESUMO

INTRODUCTION: This study aimed to determine the prevalence of menopausal symptoms, its effect to the quality of life and their treatment seeking behaviour in a multiracial community in Malaysia. METHODS: This is a cross-sectional study involving postmenopausal women in Klang Valley, Malaysia. Data was obtained by face-to-face interview using standardised questionnaires on sociodemographic data, Menopause Rating Scale questionnaire, effect to quality of life and treatment sought. RESULTS: A total of 258 women, including Malays (82%), Indians (14.1%) and Chinese (3.9%) were recruited. The median age was 58 (range 45-86) years old. Joint and muscular discomfort (73.3%) and fatigue (59.3%) were the most prevalent symptoms. Significant association with ethnicity were demonstrated with Malays was found to have 3.1 times higher incidence of sexual problems than Indians, (Odds Ratio (OR) 3.103; 95%CI 1.209, 7.967) and Indian had 2.6 times higher incidence of irritability compared to Malays (OR 2.598; 95%CI 1.126, 5.992). Fifty-two percent of women felt that menopausal symptoms affected their quality of life but there were only 2.7% who were severely affected. There were 24.8% of women who sought treatment and only 20.3% of those who took hormone replacement therapy. There was no significant association found between their treatment seeking behaviour in association with ethnicity, age, parity, marital and occupational status. CONCLUSION: Menopausal symptoms were prevalent among menopausal women, although only a small group of women who were severely affected. There was a lack of tendency in seeking treatment for menopausal symptoms among the women.


Assuntos
Menopausa , Aceitação pelo Paciente de Cuidados de Saúde , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Malásia/epidemiologia , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Prevalência , Inquéritos e Questionários
5.
Mater Sci Eng C Mater Biol Appl ; 75: 752-759, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28415525

RESUMO

The mechanical, thermal, and morphological properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA) based scaffold were investigated. In this study, a scaffold containing P. purpureum and PLA was produced using the solvent casting and particulate leaching method. P. purpureum fibre, also locally known as Napier grass, is composed of 46% cellulose, 34% hemicellulose, and 20% lignin. PLA composites with various P. purpureum contents (10%, 20%, and 30%) were prepared and subsequently characterised. The morphologies, structures and thermal behaviours of the prepared composite scaffolds were characterised using field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The morphology was studied using FESEM; the scaffold possessed 70-200µm-sized pores with a high level of interconnectivity. The moisture content and mechanical properties of the developed porous scaffolds were further characterised. The P. purpureum/PLA scaffold had a greater porosity factor (99%) and compression modulus (5.25MPa) than those of the pure PLA scaffold (1.73MPa). From the results, it can be concluded that the properties of the highly porous P. purpureum/PLA scaffold developed in this study can be controlled and optimised. This can be used to facilitate the construction of implantable tissue-engineered cartilage.


Assuntos
Materiais Biocompatíveis/química , Pennisetum/química , Poliésteres/química , Alicerces Teciduais/química , Força Compressiva , Teste de Materiais , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Engenharia Tecidual/métodos
6.
Arch Biochem Biophys ; 605: 76-85, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27046340

RESUMO

Cold plasma is partly ionized non-thermal plasma generated at atmospheric pressure. It has been recognized as an alternative approach in medicine for sterilization of wounds, promotion of wound healing, topical treatment of skin diseases with microbial involvement and treatment of cancer. Cold plasma used in wound therapy inhibits microbes in chronic wound due to its antiseptic effects, while promoting healing by stimulation of cell proliferation and migration of wound relating skin cells. In this study, two types of plasma systems are employed to generate cold plasma: a parallel plate dielectric barrier discharge and a capillary-guided corona discharge. Parameters such as applied voltage, discharge frequency, treatment time and the flow of the carrier gas influence the cold plasma chemistry and therefore change the composition and concentration of plasma species that react with the target sample. Chronic wound that fails to heal often infected by multidrug resistant organisms makes them recalcitrant to healing. Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (Pseudomonas aeruginosa) are two common bacteria in infected and clinically non-infected wounds. The efficacies of the cold plasma generated by the two designs on the inactivation of three different isolates of MRSA and four isolates of P. aeruginosa are reported here.


Assuntos
Gases em Plasma , Pseudomonas aeruginosa , Staphylococcus aureus , Cicatrização , Ferimentos e Lesões/microbiologia , Pressão Atmosférica , Infecções Bacterianas/prevenção & controle , Proliferação de Células , Temperatura Baixa , Farmacorresistência Bacteriana , Humanos , Meticilina/química , Ferimentos e Lesões/terapia
7.
Australas Phys Eng Sci Med ; 30(4): 288-91, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18274069

RESUMO

Percutaneous image-guided needle biopsy is typically performed in highly vascular organs or in tumours with rich macroscopic and microscopic blood supply. The main risks related to this procedure are haemorrhage and implantation of tumour cells in the needle tract after the biopsy needle is withdrawn. From numerous conducted studies, it was found that heating the needle tract using alternating current in radiofrequency (RF) range has a potential to minimize these effects. However, this solution requires the use of specially designed needles, which would make the procedure relatively expensive and complicated. Thus, we propose a simple solution by using readily available coaxial core biopsy needles connected to a radiofrequency ablation (RFA) generator. In order to do so, we have designed and developed an adapter to interface between these two devices. For evaluation purpose, we used a bovine liver as a sample tissue. The experimental procedure was done to study the effect of different parameter settings on the size of coagulation necrosis caused by the RF current heating on the subject. The delivery of the RF energy was varied by changing the values for delivered power, power delivery duration, and insertion depth. The results showed that the size of the coagulation necrosis is affected by all of the parameters tested. In general, the size of the region is enlarged with higher delivery of RF power, longer duration of power delivery, and shallower needle insertion and become relatively constant after a certain value. We also found that the solution proposed provides a low cost and practical way to minimizes unwanted post-biopsy effects.


Assuntos
Biópsia por Agulha/instrumentação , Terapia por Radiofrequência , Animais , Biópsia por Agulha/efeitos adversos , Biópsia por Agulha/economia , Bovinos , Custos e Análise de Custo , Temperatura Alta/uso terapêutico , Humanos , Inoculação de Neoplasia , Neoplasias/diagnóstico , Hemorragia Pós-Operatória/prevenção & controle , Cirurgia Assistida por Computador
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