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1.
Biomater Adv ; 161: 213854, 2024 Apr 16.
Article En | MEDLINE | ID: mdl-38703541

This review delves into the utilization of intermetallic alloys (IMAs) as advanced biomaterials for medical implants, scrutinizing their conceptual framework, fabrication challenges, and diverse manufacturing techniques such as casting, powder metallurgy, and additive manufacturing. Manufacturing techniques such as casting, powder metallurgy, additive manufacturing, and injection molding are discussed, with specific emphasis on achieving optimal grain sizes, surface roughness, and mechanical properties. Post-treatment methods aimed at refining surface quality, dimensional precision, and mechanical properties of IMAs are explored, including the use of heat treatments to enhance biocompatibility and corrosion resistance. The review presents an in-depth examination of IMAs-based implantable biomaterials, covering lab-scale developments and commercial-scale implants. Specific IMAs such as Nickel Titanium, Titanium Aluminides, Iron Aluminides, Magnesium-based IMAs, Zirconium-based IMAs, and High-entropy alloys (HEAs) are highlighted, with detailed discussions on their mechanical properties, including strength, elastic modulus, and corrosion resistance. Future directions are outlined, with an emphasis on the anticipated growth in the orthopedic devices market and the role of IMAs in meeting this demand. The potential of porous IMAs in orthopedics is explored, with emphasis on achieving optimal pore sizes and distributions for enhanced osseointegration. The review concludes by highlighting the ongoing need for research and development efforts in IMAs technologies, including advancements in design and fabrication techniques.

2.
Comput Biol Med ; 172: 108207, 2024 Apr.
Article En | MEDLINE | ID: mdl-38489986

Artificial Intelligence (AI) techniques are increasingly used in computer-aided diagnostic tools in medicine. These techniques can also help to identify Hypertension (HTN) in its early stage, as it is a global health issue. Automated HTN detection uses socio-demographic, clinical data, and physiological signals. Additionally, signs of secondary HTN can also be identified using various imaging modalities. This systematic review examines related work on automated HTN detection. We identify datasets, techniques, and classifiers used to develop AI models from clinical data, physiological signals, and fused data (a combination of both). Image-based models for assessing secondary HTN are also reviewed. The majority of the studies have primarily utilized single-modality approaches, such as biological signals (e.g., electrocardiography, photoplethysmography), and medical imaging (e.g., magnetic resonance angiography, ultrasound). Surprisingly, only a small portion of the studies (22 out of 122) utilized a multi-modal fusion approach combining data from different sources. Even fewer investigated integrating clinical data, physiological signals, and medical imaging to understand the intricate relationships between these factors. Future research directions are discussed that could build better healthcare systems for early HTN detection through more integrated modeling of multi-modal data sources.


Hypertension , Medicine , Humans , Artificial Intelligence , Electrocardiography , Hypertension/diagnostic imaging , Magnetic Resonance Angiography
3.
Healthcare (Basel) ; 11(14)2023 Jul 08.
Article En | MEDLINE | ID: mdl-37510421

The prevalence of vaping worldwide is showing an upward trend. This study aimed to determine the factors associated with motivation to quit vaping among vapers in the Federal Territory of Kuala Lumpur, Malaysia, through a cross-sectional, purposive sampling study. Respondents were required to complete a questionnaire consisting of vapers' sociodemographic questions, habitual behavioral pattern questions, the e-Fagerström Test of Nicotine Dependence, the Glover-Nilsson Smoking Behavioral Dependence Questionnaire, perception questions, motivation to quit questions, and withdrawal symptom questions. A total of 311 vapers participated in this study. The majority of the vapers were male (84.6%), younger (18-25 years) (55.3%), and with monthly income less than RM 4000 (USD 868; 83.9%). The level of motivation to quit vaping was found to have a significant association with the perception of vaping being as satisfying as cigarette smoking (p = 0.006) and mild to very strong nicotine dependence (p = 0.001). Participants who recorded moderate and strong habitual vaping behaviors had lower odds of having high motivation to quit vaping compared to those recording slight habitual behaviors (OR = 0.279, 95%CI(0.110-0.708), p = 0.007 and OR = 0.185, 95%CI(0.052-0.654), p = 0.009, respectively). Factors associated with higher motivation to quit vaping could be explored to gain better understanding of how to increase their motivation level for future quit attempts.

4.
J Labelled Comp Radiopharm ; 66(10): 308-320, 2023 08.
Article En | MEDLINE | ID: mdl-37287213

Transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) are promising treatments for unresectable liver tumours. Some recent studies suggested that combining TACE and TARE in one treatment course might improve treatment efficacy through synergistic cytotoxicity effects. Nonetheless, current formulations do not facilitate a combination of chemo- and radio-embolic agents in one delivery system. Therefore, this study aimed to synthesise a hybrid biodegradable microsphere loaded with both radioactive agent, samarium-153 (153 Sm) and chemotherapeutic drug, doxorubicin (Dox) for potential radio-chemoembolization of advanced liver tumours. 152 Sm and Dox-loaded polyhydroxybutyrate-co-3-hydroxyvalerate (PHBV) microspheres were prepared using water-in-oil-in-water solvent evaporation method. The microspheres were then sent for neutron activation in a neutron flux of 2 × 1012 n/cm2 /s. The physicochemical properties, radioactivity, radionuclide purity, 153 Sm retention efficiency, and Dox release profile of the Dox-153 Sm-PHBV microspheres were analysed. In addition, in vitro cytotoxicity of the formulation was tested using MTT assay on HepG2 cell line at 24 and 72 h. The mean diameter of the Dox-153 Sm-PHBV microspheres was 30.08 ± 2.79 µm. The specific radioactivity was 8.68 ± 0.17 GBq/g, or 177.69 Bq per microsphere. The 153 Sm retention efficiency was more than 99%, tested in phosphate-buffered saline (PBS) and human blood plasma over 26 days. The cumulative release of Dox from the microspheres after 41 days was 65.21 ± 1.96% and 29.96 ± 0.03% in PBS solution of pH 7.4 and pH 5.5, respectively. The Dox-153 Sm-PHBV microspheres achieved a greater in vitro cytotoxicity effect on HepG2 cells (85.73 ± 3.63%) than 153 Sm-PHBV (70.03 ± 5.61%) and Dox-PHBV (74.06 ± 0.78%) microspheres at 300 µg/mL at 72 h. In conclusion, a novel biodegradable microspheres formulation loaded with chemotherapeutic drug (Dox) and radioactive agent (153 Sm) was successfully developed in this study. The formulation fulfilled all the desired physicochemical properties of a chemo-radioembolic agent and achieved better in vitro cytotoxicity on HepG2 cells. Further investigations are needed to evaluate the biosafety, radiation dosimetry, and synergetic anticancer properties of the formulation.


Carcinoma, Hepatocellular , Chemoembolization, Therapeutic , Liver Neoplasms , Humans , Liver Neoplasms/therapy , Microspheres , Chemoembolization, Therapeutic/methods , Doxorubicin/pharmacology , Doxorubicin/therapeutic use , Radioisotopes/therapeutic use , Polyesters/therapeutic use
5.
Pharmaceutics ; 15(3)2023 Mar 08.
Article En | MEDLINE | ID: mdl-36986738

Radioembolization shows great potential as a treatment for intermediate- and advanced-stage liver cancer. However, the choices of radioembolic agents are currently limited, and hence the treatment is relatively costly compared to other approaches. In this study, a facile preparation method was developed to produce samarium carbonate-polymethacrylate [152Sm2(CO3)3-PMA] microspheres as neutron activatable radioembolic microspheres for hepatic radioembolization. The developed microspheres emits both therapeutic beta and diagnostic gamma radiations for post-procedural imaging. The 152Sm2(CO3)3-PMA microspheres were produced from commercially available PMA microspheres through the in situ formation of 152Sm2(CO3)3 within the pores of the PMA microspheres. Physicochemical characterization, gamma spectrometry and radionuclide retention assay were performed to evaluate the performance and stability of the developed microspheres. The mean diameter of the developed microspheres was determined as 29.30 ± 0.18 µm. The scanning electron microscopic images show that the spherical and smooth morphology of the microspheres remained after neutron activation. The 153Sm was successful incorporated into the microspheres with no elemental and radionuclide impurities produced after neutron activation, as indicated by the energy dispersive X-ray analysis and gamma spectrometry. Fourier transform infrared spectroscopy confirmed that there was no alteration to the chemical groups of the microspheres after neutron activation. After 18 h of neutron activation, the microspheres produced an activity of 4.40 ± 0.08 GBq.g-1. The retention of 153Sm on the microspheres was greatly improved to greater than 98% over 120 h when compared to conventionally radiolabeling method at ~85%. The 153Sm2(CO3)3-PMA microspheres achieved suitable physicochemical properties as theragnostic agent for hepatic radioembolization and demonstrated high radionuclide purity and 153Sm retention efficiency in human blood plasma.

6.
Micromachines (Basel) ; 14(2)2023 Feb 16.
Article En | MEDLINE | ID: mdl-36838164

3D printing has been increasingly used for medical applications with studies reporting its value, ranging from medical education to pre-surgical planning and simulation, assisting doctor-patient communication or communication with clinicians, and the development of optimal computed tomography (CT) imaging protocols. This article presents our experience of utilising a 3D-printing facility to print a range of patient-specific low-cost models for medical applications. These models include personalized models in cardiovascular disease (from congenital heart disease to aortic aneurysm, aortic dissection and coronary artery disease) and tumours (lung cancer, pancreatic cancer and biliary disease) based on CT data. Furthermore, we designed and developed novel 3D-printed models, including a 3D-printed breast model for the simulation of breast cancer magnetic resonance imaging (MRI), and calcified coronary plaques for the simulation of extensive calcifications in the coronary arteries. Most of these 3D-printed models were scanned with CT (except for the breast model which was scanned using MRI) for investigation of their educational and clinical value, with promising results achieved. The models were confirmed to be highly accurate in replicating both anatomy and pathology in different body regions with affordable costs. Our experience of producing low-cost and affordable 3D-printed models highlights the feasibility of utilizing 3D-printing technology in medical education and clinical practice.

7.
Pharmaceutics ; 15(2)2023 Feb 06.
Article En | MEDLINE | ID: mdl-36839858

Introduction: Neutron-activated samarium-153-oxide-loaded polystyrene ([153Sm]Sm2O3-PS) microspheres has been developed in previous study as a potential theranostic agent for hepatic radioembolization. In this study, the therapeutic efficacy and diagnostic imaging capabilities of the formulation was assessed using liver cancer Sprague-Dawley (SD) rat model. Methods: Twelve male SD rats (150-200 g) that implanted with N1-S1 hepatoma cell line orthotopically were divided into two groups (study versus control) to monitor the tumour growth along 60 days of treatment. The study group received an intra-tumoural injection of approximately 37 MBq of [153Sm]Sm2O3-PS microspheres, while control group received an intra-tumoural injection of 0.1 mL of saline solution. A clinical single photon emission computed tomography/computed tomography (SPECT/CT) system was used to scan the rats at Day 5 post-injection to investigate the diagnostic imaging capabilities of the microspheres. All rats were monitored for change in tumour volume using a portable ultrasound system throughout the study period. Histopathological examination (HPE) was performed after the rats were euthanized at Day 60. Results: At Day 60, no tumour was observed on the ultrasound images of all rats in the study group. In contrast, the tumour volumes in the control group were 24-fold larger compared to baseline. Statistically significant difference was observed in tumour volumes between the study and control groups (p < 0.05). The SPECT/CT images clearly displayed the location of [153Sm]Sm2O3-PS in the liver tumour of all rats at Day 5 post-injection. Additionally, the [153Sm]Sm2O3-PS microspheres was visible on the CT images and this has added to the benefits of 153Sm as a CT contrast agent. The HPE results showed that the [153Sm]Sm2O3-PS microspheres remained concentrated at the injection site with no tumour cells observed in the study group. Conclusions: Neutron-activated [153Sm]Sm2O3-PS microspheres demonstrated excellent therapeutic and diagnostic imaging capabilities for theranostic treatment of liver cancer in a SD rat model. Further studies with different animal and tumour models are planned to validate this finding.

8.
Nucl Med Commun ; 44(4): 227-243, 2023 Apr 01.
Article En | MEDLINE | ID: mdl-36808108

Personalised cancer treatment is of growing importance and can be achieved via targeted radionuclide therapy. Radionuclides with theranostic properties are proving to be clinically effective and are widely used because diagnostic imaging and therapy can be accomplished using a single formulation that avoids additional procedures and unnecessary radiation burden to the patient. For diagnostic imaging, single photon emission computed tomography (SPECT) or positron emission tomography (PET) is used to obtain functional information noninvasively by detecting the gamma (γ) rays emitted from the radionuclide. For therapeutics, high linear energy transfer (LET) radiations such as alpha (α), beta (ß - ) or Auger electrons are used to kill cancerous cells in close proximity, whereas sparing the normal tissues surrounding the malignant tumour cells. One of the most important factors that lead to the sustainable development of nuclear medicine is the availability of functional radiopharmaceuticals. Nuclear research reactors play a vital role in the production of medical radionuclides for incorporation into clinical radiopharmaceuticals. The disruption of medical radionuclide supplies in recent years has highlighted the importance of ongoing research reactor operation. This article reviews the current status of operational nuclear research reactors in the Asia-Pacific region that have the potential for medical radionuclide production. It also discusses the different types of nuclear research reactors, their operating power, and the effects of thermal neutron flux in producing desirable radionuclides with high specific activity for clinical applications.


Radioisotopes , Radiopharmaceuticals , Humans , Radiopharmaceuticals/therapeutic use , Radioisotopes/therapeutic use , Tomography, Emission-Computed, Single-Photon , Positron-Emission Tomography , Radionuclide Imaging
9.
Inform Med Unlocked ; 36: 101158, 2023.
Article En | MEDLINE | ID: mdl-36618887

Background: Chest computed tomography (CT) has a high sensitivity for detecting COVID-19 lung involvement and is widely used for diagnosis and disease monitoring. We proposed a new image classification model, swin-textural, that combined swin-based patch division with textual feature extraction for automated diagnosis of COVID-19 on chest CT images. The main objective of this work is to evaluate the performance of the swin architecture in feature engineering. Material and method: We used a public dataset comprising 2167, 1247, and 757 (total 4171) transverse chest CT images belonging to 80, 80, and 50 (total 210) subjects with COVID-19, other non-COVID lung conditions, and normal lung findings. In our model, resized 420 × 420 input images were divided using uniform square patches of incremental dimensions, which yielded ten feature extraction layers. At each layer, local binary pattern and local phase quantization operations extracted textural features from individual patches as well as the undivided input image. Iterative neighborhood component analysis was used to select the most informative set of features to form ten selected feature vectors and also used to select the 11th vector from among the top selected feature vectors with accuracy >97.5%. The downstream kNN classifier calculated 11 prediction vectors. From these, iterative hard majority voting generated another nine voted prediction vectors. Finally, the best result among the twenty was determined using a greedy algorithm. Results: Swin-textural attained 98.71% three-class classification accuracy, outperforming published deep learning models trained on the same dataset. The model has linear time complexity. Conclusions: Our handcrafted computationally lightweight swin-textural model can detect COVID-19 accurately on chest CT images with low misclassification rates. The model can be implemented in hospitals for efficient automated screening of COVID-19 on chest CT images. Moreover, findings demonstrate that our presented swin-textural is a self-organized, highly accurate, and lightweight image classification model and is better than the compared deep learning models for this dataset.

10.
Asian Pac J Cancer Prev ; 24(1): 37-47, 2023 Jan 01.
Article En | MEDLINE | ID: mdl-36708550

BACKGROUND: Cancer remains a challenging target to cure, with present therapeutic methods unable to exhibit restorative outcomes without causing severe negative effects. Molecular hydrogen (H2) has been reported to be a promising adjunctive therapy for cancer treatment, having the capability to induce anti-proliferative, anti-oxidative, pro-apoptotic and anti-tumoural effects. This review summarises the findings from various articles on the mechanism, treatment outcomes, and overall effectiveness of H2 therapy on cancer management. METHODS: Using Cochrane, PubMed, and Google Scholar as the search engines, full-text articles in the scope of the study, written in English and within 10 years of publication were selected. RESULTS: Out of the 677 articles, 27 articles fulfilled the eligibility criteria, where data was compiled into a table, outlining the general characteristics and findings. Throughout the different forms of H2 administration, study design and types of cancers reported, outcomes were found to be consistent. CONCLUSION: From our analysis, H2 plays a promising therapeutic role as an independent therapy as well as an adjuvant in combination therapy, resulting in an overall improvement in survivability, quality of life, blood parameters, and tumour reduction. Although more comprehensive research is needed, given the promising outcomes, H2 is worth considering for use as a complement to current cancer therapy.


Neoplasms , Quality of Life , Humans , Neoplasms/drug therapy , Treatment Outcome
11.
Med Phys ; 49(12): 7742-7753, 2022 Dec.
Article En | MEDLINE | ID: mdl-36098271

PURPOSE: Monte Carlo (MC) simulation is an important technique that can help design advanced and challenging experimental setups. GATE (Geant4 application for tomographic emission) is a useful simulation toolkit for applications in nuclear medicine. Transarterial radioembolization is a treatment for liver cancer, where microspheres embedded with yttrium-90 (90 Y) are administered intra-arterially to the tumor. Personalized dosimetry for this treatment may provide higher dosimetry accuracy compared to the conventional partition model (PM) calculation. However, incorporation of three-dimensional tomographic input data into MC simulation is an intricate process. In this article, 3D Slicer, free and open-source software, was utilized for the incorporation of patient tomographic images into GATE to demonstrate the feasibility of personalized dosimetry in hepatic radioembolization with 90 Y. METHODS: In this article, the steps involved in importing, segmenting, and registering tomographic images using 3D Slicer were thoroughly described, before importing them into GATE for MC simulation. The absorbed doses estimated using GATE were then compared with that of PM. SlicerRT, a 3D Slicer extension, was then used to visualize the isodose from the MC simulation. RESULTS: A workflow diagram consisting of all the steps taken in the utilization of 3D Slicer for personalized dosimetry in 90 Y radioembolization has been presented in this article. In comparison to the MC simulation, the absorbed doses to the tumor and normal liver were overestimated by PM by 105.55% and 20.23%, respectively, whereas for lungs, the absorbed dose estimated by PM was underestimated by 25.32%. These values were supported by the isodose distribution obtained via SlicerRT, suggesting the presence of beta particles outside the volumes of interest. These findings demonstrate the importance of personalized dosimetry for a more accurate absorbed dose estimation compared to PM. CONCLUSION: The methodology provided in this study can assist users (especially students or researchers who are new to MC simulation) in navigating intricate steps required in the importation of tomographic data for MC simulation. These steps can also be utilized for other radiation therapy related applications, not necessarily limited to internal dosimetry.


Liver Neoplasms , Yttrium Radioisotopes , Humans , Monte Carlo Method , Yttrium Radioisotopes/therapeutic use , Computer Simulation , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/radiotherapy , Radiometry/methods
12.
Nucl Med Commun ; 43(4): 410-422, 2022 Apr 01.
Article En | MEDLINE | ID: mdl-35045548

PURPOSE: Hepatic radioembolization is an effective minimally invasive treatment for primary and metastatic liver cancers. Yttrium-90 [90Y]-labelled resin or glass beads are typically used as the radioembolic agent for this treatment; however, these are not readily available in many countries. In this study, novel samarium-153 oxide-loaded polystyrene ([153Sm]Sm2O3-PS) microspheres were developed as a potential alternative to 90Y microspheres for hepatic radioembolization. METHODS: The [152Sm]Sm2O3-PS microspheres were synthesized using solid-in-oil-in-water solvent evaporation. The microspheres underwent neutron activation using a 1 MW open-pool research reactor to produce radioactive [153Sm]Sm2O3-PS microspheres via 152Sm(n,γ)153Sm reaction. Physicochemical characterization, gamma spectroscopy and in-vitro radionuclide retention efficiency were carried out to evaluate the properties and stability of the microspheres before and after neutron activation. RESULTS: The [153Sm]Sm2O3-PS microspheres achieved specific activity of 5.04 ± 0.52 GBq·g-1 after a 6 h neutron activation. Scanning electron microscopy and particle size analysis showed that the microspheres remained spherical with an average diameter of ~33 µm before and after neutron activation. No long half-life radionuclide and elemental impurities were found in the samples. The radionuclide retention efficiencies of the [153Sm]Sm2O3-PS microspheres at 550 h were 99.64 ± 0.07 and 98.76 ± 1.10% when tested in saline solution and human blood plasma, respectively. CONCLUSIONS: A neutron-activated [153Sm]Sm2O3-PS microsphere formulation was successfully developed for potential application as a theranostic agent for liver radioembolization. The microspheres achieved suitable physical properties for radioembolization and demonstrated high radionuclide retention efficiency in saline solution and human blood plasma.


Yttrium Radioisotopes
13.
Acad Radiol ; 29(4): e39-e48, 2022 04.
Article En | MEDLINE | ID: mdl-33992535

RATIONALE AND OBJECTIVES: Molecular studies have shown the changes in bone marrow fat in relation to altered hematopoiesis. This study aims to investigate the changes in the bone marrow fat in patients affected by ß-thalassemia by using chemical shift-encoded (CSE)-MRI. MATERIALS AND METHODS: Twenty-three subjects, comprising of six healthy (17-31 years old) and 17 ß-thalassemia subjects (19-39 years old), were scanned using a multiecho fast low angle shot sequence (0.94 × 0.94 × 3.00 mm3) and a stimulated echo acquisition mode sequence using 3T MRI. Bone marrow proton density fat fraction (PDFF) was quantified in the left femur of each subject. Regression and Bland-Altman analysis were used to analyze agreement between CSE-MRI and 1H-MRS. PDFF distribution was analyzed using Hartigan's dip test and the computed Wasserstein distances. Jonckheere-Terpstra trend analysis was performed to evaluate the effect of disease severity on PDFF distribution. RESULTS: An excellent agreement was found between PDFF measured using CSE-MRI with 1H-MRS (R2 = 0.91; bias =-1.41%). Healthy subjects showed left-skewed or bimodal PDFF distribution while ß-thalassemia subjects showed bimodal, normal or right-skewed distribution. Jonckheere-Terpstra test shows that PDFF distribution was increasingly different from the norm as disease severity increased (TJT = 166.0, z = 3.806, p < 0.05). Increase in variability of PDFF distribution within each subject group was also seen with increasing disease severity (TJT = 169.0, z = 3.971, p < 0.05). CONCLUSION: CSE-MRI is a promising tool to demonstrate spatial changes and variability in marrow fat distribution, resulting from ineffective erythropoiesis.


Bone Marrow , beta-Thalassemia , Adipose Tissue/diagnostic imaging , Adolescent , Adult , Bone Marrow/diagnostic imaging , Humans , Liver , Magnetic Resonance Imaging/methods , Prospective Studies , Water , Young Adult , beta-Thalassemia/diagnostic imaging
14.
Health Technol (Berl) ; 11(5): 1149-1163, 2021.
Article En | MEDLINE | ID: mdl-34485010

This article aims to highlight some of the contributions from Bangladeshi and Malaysian women scientists in the fields of health informatics, medical physics and biomedical engineering, and veterinary science in combating the COVID-19 world crisis. The status of COVID-19 situations in Bangladesh and Malaysia in respect to global scenario, some relevant government policies, lessons learnt from previous pandemics, socio-economic impacts of COVID-19, the impact on healthcare system and health management approaches taken by individual/institutional research group led by women scientists during the COVID-19 pandemic have been discussed and demonstrated in this article. These promising activities and initiatives will eventually motivate other women in science and extend their roles from laboratory to society in more aspects.

15.
Biomolecules ; 11(9)2021 09 03.
Article En | MEDLINE | ID: mdl-34572520

The diagnostic value of coronary computed tomography angiography (CCTA) is significantly affected by high calcification in the coronary arteries owing to blooming artifacts limiting its accuracy in assessing the calcified plaques. This study aimed to simulate highly calcified plaques in 3D-printed coronary models. A combination of silicone + 32.8% calcium carbonate was found to produce 800 HU, representing extensive calcification. Six patient-specific coronary artery models were printed using the photosensitive polyurethane resin and a total of 22 calcified plaques with diameters ranging from 1 to 4 mm were inserted into different segments of these 3D-printed coronary models. The coronary models were scanned on a 192-slice CT scanner with 70 kV, pitch of 1.4, and slice thickness of 1 mm. Plaque attenuation was measured between 1100 and 1400 HU. Both maximum-intensity projection (MIP) and volume rendering (VR) images (wide and narrow window widths) were generated for measuring the diameters of these calcified plaques. An overestimation of plaque diameters was noticed on both MIP and VR images, with measurements on the MIP images close to those of the actual plaque sizes (<10% deviation), and a large measurement discrepancy observed on the VR images (up to 50% overestimation). This study proves the feasibility of simulating extensive calcification in coronary arteries using a 3D printing technique to develop calcified plaques and generate 3D-printed coronary models.


Artifacts , Calcinosis/pathology , Coronary Vessels/pathology , Plaque, Atherosclerotic/pathology , Printing, Three-Dimensional , Humans , Tomography, X-Ray Computed
17.
Phys Med ; 82: 40-45, 2021 Feb.
Article En | MEDLINE | ID: mdl-33581616

PURPOSE: To investigate the efficacy of a newly-developed laser-heated core biopsy needle in the thermal ablation of biopsy tract to reduce hemorrhage after biopsy using in vivo rabbit's liver model. MATERIALS AND METHODS: Five male New Zealand White rabbits weighed between 1.5 and 4.0 kg were anesthetized and their livers were exposed. 18 liver biopsies were performed under control group (without tract ablation, n = 9) and study group (with tract ablation, n = 9) settings. The needle insertion depth (~3 cm) and rate of retraction (~3 mm/s) were fixed in all the experiments. For tract ablation, three different needle temperatures (100, 120 and 150 °C) were compared. The blood loss at each biopsy site was measured by weighing the gauze pads before and after blood absorption. The rabbits were euthanized immediately and the liver specimens were stained with hematoxylin-eosin (H&E) for further histopathological examination (HPE). RESULTS: The average blood loss in the study group was reduced significantly (p < 0.05) compared to the control group. The highest percentage of bleeding reduction was observed at the needle temperature of 150 °C (93.8%), followed by 120 °C (85.8%) and 100 °C (84.2%). The HPE results show that the laser-heated core biopsy needle was able to cause lateral coagulative necrosis up to 14 mm diameter along the ablation tract. CONCLUSION: The laser-heated core biopsy needle reduced hemorrhage up to 93.8% and induced homogenous coagulative necrosis along the ablation tract in the rabbits' livers. This could potentially reduce the risk of tumor seeding in clinical settings.


Hemorrhage , Liver , Animals , Biopsy, Needle , Hot Temperature , Lasers , Male , Rabbits
18.
Sci Rep ; 11(1): 2299, 2021 01 27.
Article En | MEDLINE | ID: mdl-33504909

Microwave ablation (MWA) is gaining popularity for the treatment of small primary hepatocellular carcinoma and metastatic lesions especially if patients are not candidates for surgical resection. Deep neuromuscular blockade (DMB) is perceived to improve surgical working conditions compared to moderate neuromuscular blockade (MMB) but no studies have examined the same benefits in MWA of liver tumours. This study aimed to compare the clinical outcomes of DMB and MMB in MWA of liver tumours in terms of liver excursion, performance scores by the interventional radiologists and patients, requirements of additional muscle relaxants and complications. 50 patients were recruited and 45 patients (22 in MMB group, 23 in DMB group) completed the study. The mean liver excursion for the MMB group (1.42 ± 1.83 mm) was significantly higher than the DMB group (0.26 ± 0.38 mm) (p = 0.001). The mean Leiden-Surgical Rating Scale (L-SRS) rated by the two interventional radiologists were 4.5 ± 0.59 and 3.6 ± 0.85 for the DMB and MMB groups, respectively (p = 0.01). There was also statistically significant difference on patient satisfaction scores (0-10: Extremely Dissatisfied-Extremely Satisfied) between DMB (8.74 ± 1.1) and MMB (7.86 ± 1.25) groups (p = 0.01). 5 patients from MMB group and none from DMB group required bolus relaxant during the MWA procedure. Adverse events were also noted to be more severe in the MMB group. In conclusion, DMB significantly reduced liver excursion and movement leading to improved accuracy, safety and success in ablating liver tumour.


Carcinoma, Hepatocellular/therapy , Liver Neoplasms/therapy , Microwaves , Neuromuscular Blockade/methods , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Prospective Studies , Randomized Controlled Trials as Topic
19.
Ceram Int ; 47(3): 2917-2948, 2021 Feb 01.
Article En | MEDLINE | ID: mdl-32994658

Nanomedicine has seen a significant rise in the development of new research tools and clinically functional devices. In this regard, significant advances and new commercial applications are expected in the pharmaceutical and orthopedic industries. For advanced orthopedic implant technologies, appropriate nanoscale surface modifications are highly effective strategies and are widely studied in the literature for improving implant performance. It is well-established that implants with nanotubular surfaces show a drastic improvement in new bone creation and gene expression compared to implants without nanotopography. Nevertheless, the scientific and clinical understanding of mixed oxide nanotubes (MONs) and their potential applications, especially in biomedical applications are still in the early stages of development. This review aims to establish a credible platform for the current and future roles of MONs in nanomedicine, particularly in advanced orthopedic implants. We first introduce the concept of MONs and then discuss the preparation strategies. This is followed by a review of the recent advancement of MONs in biomedical applications, including mineralization abilities, biocompatibility, antibacterial activity, cell culture, and animal testing, as well as clinical possibilities. To conclude, we propose that the combination of nanotubular surface modification with incorporating sensor allows clinicians to precisely record patient data as a critical contributor to evidence-based medicine.

20.
JPEN J Parenter Enteral Nutr ; 45(2): 422-426, 2021 02.
Article En | MEDLINE | ID: mdl-32384179

BACKGROUND: Muscle wasting, prevalent in maintenance hemodialysis (HD) patients diagnosed with protein-energy wasting, represents an assessment challenge in the outpatient HD setting. Quadriceps muscle thickness (QMT) and cross-sectional area (CSA) assessment by ultrasound (US) is a potential surrogate measure for muscle wasting. We aimed to determine the validity of US to measure QMT and CSA against the gold standard-computed tomography (CT). METHODS: Twenty-six patients on HD underwent US and CT scans on the same day, postdialysis session. QMT for rectus femoris (RF) and vastus intermedius (VI) muscles was taken at the midpoint (MID) and two-thirds (2/3) of both thighs and CSA of the RF muscle (RFCSA ), respectively. Correlation between US and CT measurements was determined by intraclass correlation coefficient (ICC) and Bland-Altman plot. RESULTS: ICC (95% CI) computed between US and CT was 0.94 (0.87-0.97), 0.97 (0.93-0.99), 0.94 (0.87-0.97), 0.94 (0.86-0.97), and 0.92 (0.83-0.97) for RFMID, VIMID, RF2/3, VI2/3 , and RFCSA , respectively (all P < 0.001). Bland-Altman analysis indicated no bias in agreement between both methods. CONCLUSION: The US imaging offers a valid and quick bedside assessment approach to assess muscle wasting in HD patients.


Quadriceps Muscle , Renal Dialysis , Cachexia , Humans , Quadriceps Muscle/diagnostic imaging , Tomography, X-Ray Computed , Ultrasonography
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