Institut Perubatan & Pergigian Termaju - Tesis

Browse

Now showing 1 - 20 of 143

Optimization Of Immunoillstochemistry: Testing For Mlhl And Msh2 Proteins In Colon Tissue
(2005-05)
Muhsain, Siti Nur Fadzilah
Microsatellite instability (MSI) accounts for the development of about 15% of all colorectal cancers. It is characterized by mutations in mismatch repair (MMR) genes that render cells unable to detect errors during DNA replication. Mutations in the MMR genes, MLHl and MSH2 are responsible for the majority of CRC with MSI. These MMR proteins can be detected by immunohistochemistry (lllC). IHC has proved sensitive and specific when compared to molecular analysis of MSI. Nevertheless, generally, there is no published literature as yet on studies of MSI in Malaysia, and specifically using lliC. Before any lliC staining procedure can be done, it has to be optimized. In this study, attempts were made to optimize rnc staining of MLHl and MSH2 proteins using polyclonal rabbit antibody by Biovision on formalin-fixed paraffm-embedded sections of normal colon, taken from resected margins of colectomy specimens. Either Vectastain Elite ABC Kit or DAKO En Vision Kit was used as secondary detection system. The staining procedure was done using different dilutions of the primary antibodies and incubated for different durations at different temperatures. Antigen retrieval procedures were introduced using citrate buffer pH 6 or Tris-EDTA buffer pH 9. The results showed that incubation of sections at room temperature using different dilutions of antibody failed to produce any nuclear staining. Staining with DAKO En Vision was still unsatisfactory, although background staining was reduced. Introduction of antigen retrieval procedure using microwave did not improve results. When incubated at 4°C, non-specific background staining was produced.
Determination Of Epstein-barr Virus In Gastrointestinal Lymphomas (With Special Reference To Non-hodgkin's Lymphoma Of Small Intestine): Study On Malaysian Patients.
(2005-05)
Yunos, Asmah Md
Non-Hodgkin's lymphoma (NHL) is ranked twelfth among all cancers world-wide, in which it is more prevalent in males compared to females. The aim of the present study was to determine the presence and distribution of Epstein-Barr virus (EBV) in non-Hodgkin's lymphomas (NHL) of the gastrointestinal tract (GIT) tissue samples obtained from 25 Malaysian patients diagnosed clinically and histopathologically. The gastrointestinal lymphomas analysed in the present study was divided into NHL of the ileocecal (9 cases), NHL of the small intestine (7 cases), NHL of the stomach (5 cases), NHL of the abdomen (1 case), NHL of the wedge ulcer (1 case), NHL of rectum fotic (1 case) and finally NHL of the hemicolon (1 case). The presence of EBV in all of the above mentioned tissue samples, after formalin fixation and paraffin embedding was carried out by using conventional in situ hybridization technology. Two out of 25 cases of NHL of the GIT analysed in the present study, demonstrated positive signals for EBV/EBER. In the first positive case, EBV/EBER signals were located in transformed lymphocytes in the serosa layer of the small intestine (14.3%). In the second EBV positive case, EBV/EBER signals were located in diffuse B-cell lymphomas of the ileocecal (11.1 %). In conclusion, these finding demonstrate a rare association between EBV and lower gastrointestinal lymphomas (excluding stomach).
Anion Exchanger 1 Gene (AE1) Single Nucleotide Polymorphism (SNP) Analysis Among Malays With Distal Renal Tubular Acidosis (DRTA) And Southeast Asian Ovalocytosis (SAO)
(2018-08)
Anion Exchanger 1 (AE1) encoding the erythroid and kidney isoforms of AE1 protein is located on chromosome 17. Distal renal tubular acidosis (dRTA) is characterized as its inability to acidify urine pH caused by AE1 polymorphisms. Southeast Asian Ovalocytosis (SAO) is a hereditary red blood cell abnormality caused by 27bp deletions in AE1. dRTA and SAO is highly prevalent in Southeast Asian countries. Polymorphism in AE1 is known to cause both SAO and dRTA associated with 27bp deletions which is still unclear.
Association Analysis Of Single Nucleotide Polymorphism Of Opioid Dependence Genes Among Malay Males In Malaysia
(2018-09)
Nagaya, Devaki
Drug addiction is a chronic and relapsing disorder is associated with genetics. There are many studies have been reported the roles of single nucleotide polymorphisms (SNPs) with drug dependence and among those, twelve (12) candidate genes that were associated with drug dependence will be. investigated in this study. The candidate genes are OPRD1 (Delta Opioid Receptor), OPR.K1 (Kappa Opioid Receptor), COMT (Catechol — O-Methyltransferase gene), PDYN (Prodynorphin), DRD4 (Dopamine receptor D4), ABCB1(P glycoprotein), DUSP (Dual Specificity Phosphatase 27) and rs 10494334. The goal of this study was to determine the frequencies of these SNPs rsl042114, rs702764, rs 199774, rs 1022563, rs910080, rs737866, rs 10494334, rsl800955, rsl 128503, rsl045642, and rs2032582 and to study their association with opioid dependence in Malay males in Malaysian population.
Nanoencapsulation Of Thiolated Sodium Alginate: Synthesis, Drug Release And Cellular Uptake Studies
(2018-11)
Oral drug delivery has becoming the most preferred route of administration for chemotherapeutic drugs, however its application is limited due to lack of drug targeting specificity to the localised cancerous cells but not to the normal cells. Polymeric nanoparticulate drug delivery is a potential solution to deliver hydrophobic drugs specifically to colon, thus causing less side effects.
Molecular Toxico-Pathology Responses Of EUDRILUS EUGENIAE TO 2- AMINO-l-METHYL-6-PHENYLIMIDAZO[4,5- bJPYRIDINE (PhIP) AND 2-AMINO-3,8- DIMETHYLIMIDAZO [4,5-f]QUINOXALINE (MeIQx)
(2019-01)
Balogun, Wasiu Gbolahan
The carcinogenic risks of highly heated proteinaceous foods are at large associated with the formation of heterocyclic amines (HCAs), evidence in their substantial presence in the biota. The earthworm Eiidrilus eugeniae (E. eugeniae) is a terrestrial ubiquitous animal, susceptible to toxicity from environmental contamination, and a suitable model for understanding the mechanism of toxic agents such as HCAs. Thus, this study elucidated the vulnerability of E. eugeniae to HCAs induced toxicity using a modified OECD TG207 approach.
Effects Of Human Umbilical Cord-Derived Mesenchymal Stem Cells On Human Corneal Epithelial Cells’ Growth
(2019-12)
Ex vivo cultivated corneal limbal stem cell (LSC) transplantation is the contemporary therapy for comeal epithelial regeneration. The success rate of this therapy is dependent on the cell culture conditions and the carrier system. Human umbilical cord mesenchymal stem cells (hUC-MSCs) has regenerative ability and are rich with paracrine factors. Cells cultivated in spherical scaffolds could provide a similar in vivo environment to the cell niche and may positively alter the stem cells properties. This study aims to improve the cellular quality of the comeal epithelial transplantation graft using a robust cell population method. Human telomere modified comeal epithelial cells (hTCECs) were co-cultured in direct and indirect cell culture with hUC-MSCs. Characterisation of corneal markers p63, ABCG2, ABCB5, and differentiation marker K3 were performed.
Accuracy Of 131i Activity Quantification And Dosimetry In Thyroid Phantom Using 3d-image Based Spect/CT
(2021)
Mohd Yahya, Mohd Hizwan
Quantitative imaging gives a better understanding of the distribution of radioactivity that can be used in the estimation of absorbed dose in the specific target organ. The goal of this study was to obtain the accuracy of 131I activity quantification and dosimetry in thyroid uptake phantom using 3-dimensional (3D) SPECT/CT imaging. In this study, a series of SPECT/CT acquisitions of the thyroid uptake was performed. Images of different voxel sizes 64, 128, and 256 with several iterations numbers were reconstructed using ordered-subsets expectation maximization (OSEM). The quantification of the activity in the phantom was determined using a Medical Image Data Examiner (AMIDE) software based on the mean, maximum, 0.7 maximum and 0.6 maximum value. The cumulated activity in the phantom was determined by the calculating area under the curve (AUC) in the time-activity curve. The results showed that the mean value of 128 and 256 voxel show a better result with the error obtained between 4.1% and 18.2% whereas for the maximum value, it gives an overestimate count with the error up to 78%. The cumulated activity derived from SPECT/CT showed an error margin of 15%. The dosimetry result of organ absorbed dose using 3D imaged based dosimetry was approximately 16.1% lower than the absorbed dose measure using Optical Stimulated Luminescence (OSL) dosimeter. This research shows that the 3D image based SPECT/CT with good quantification accuracy capable of estimating organ absorbed dose in131I therapy.
Generation Of RNA Aptamer Against Progesterone Receptor DNA Binding Domain And Its Potential In Diagnostic And Therapeutic Applications In Breast Cancer
(2021)
Ravinderan, Presela
Aptamers are a new class of molecular recognition element that exhibit high binding affinity and specificity against the target. In this study, an RNA aptamer was generated against Progesterone Receptor DNA binding domain (PR DBD) that acts as a diagnostic biomarker and potential therapeutic target for breast cancer. Firstly, PR DBD gene was amplified and isolated from the total RNA of MCF-7 cells and cloned into pET15b plasmid. Protein expression and native purification was performed using E. coli Rosetta 2(DE3)pLysS bacterial strain. The identity of the protein was confirmed by western blot using polyclonal anti-PR antibody and by protein sequencing using MALDI-TOF/TOF mass spectrometry. The purified protein was subjected to SELEX in order to isolate RNA aptamer. A total of eight SELEX cycles were executed and the resulting nucleic acid pool from cycle 8 showed enrichment against PR DBD. The cycle 8 nucleic acid pool was sequenced using direct sequencing and crush and soak elution-based sequencing methods. Both sequencing methods revealed the presence of three different classes of sequences, with one class termed, PRapt-3 showed the strongest binding against PR DBD. The dissociation constant of PRapt-3 RNA aptamer was estimated at 380 nM ± 35 nM. PRapt-3 was successfully used to develop aptamer-based diagnostic assays such as ALISA, aptamer-based dot blot, aptamer-based western blot, aptacytostaining and aptahistostaining. PRapt-3 detected PR DBD in direct ALISA with a LOD of 69.44 nM. In the aptamer-based dot blot assay, PRapt-3 detected up to 6.25 pmol of PR DBD. PRapt-3 also successfully detected recombinant PR DBD and endogenous PR DBD in MCF-7 and HeLa cells on aptamer-based western blot assay. PRapt-3 demonstrated nuclear staining in aptacytostaining and with better penetration in aptahistostaining using the formalin fixed paraffin embedded breast cancer cell and tissue blocks. Apart from diagnostic application, the functionality of the PRapt-3 RNA aptamer was also investigated in the therapeutic applications. First, the antagonistic property of the PRapt-3 was investigated on the cell cycle analysis. Flow cytometry analysis showed that PRapt-3 RNA reduced the number of cells in S phase of MCF-7 cell cycle while reciprocally increased the percentage of cells in G0/G1. PRapt-3 can also act as a promising apoptotic inducing agent. In this study, it was found that PRapt-3 downregulated the anti-apoptotic gene, BCL-2 and upregulated the pro-apoptotic gene, BAX. PRapt-3 mitigated expression of the proliferationrelated genes. The expression level of proliferation-related genes, PI3K and AKT were reduced by PRapt-3 RNA. The downregulation of these genes showed that PRapt-3 was successfully employed to antagonize the interaction between PR and progesterone. In this entirety, PRapt-3 is a promising diagnostic and therapeutic agent.
Tooth Alignment, Coating Loss, Colour Change And Patient Perception Of Aesthetic Archwires: A Randomised Controlled Trial
(2021)
Alyassiri, Hassanin Abdulkhabeer
Aesthetic archwires help improve aesthetics of patients during orthodontic treatment. The aims of this study of randomised controlled trial (RCT) were to compare and evaluate the percentage of tooth alignment, coating loss, colour change, and patient perception of three different aesthetic superelastic nickel-titanium (SE NiTi) archwires coated with tooth-coloured polymers over eight weeks of intraoral use. Methods: Multi-centre, double-blind, randomised controlled trial was done at three centres: (1) Orthodontic Specialist Clinic, Advanced Medical & Dental Institute, Universiti Sains Malaysia (USM), (2) Orthodontic Specialist Clinic, School of Dental Sciences, USM, and (3) Desa Murni Dental Clinic, Penang. A total of 134 participants requiring upper and lower fixed appliances were recruited for this RCT. All participants were randomly allocated to one of four upper and lower archwire interventions: (1) 0.014” Orthocare Euroform® (2) 0.014” RMO FLi®, (3) 0.014” G&H, and (4) 0.014” uncoated. These three aesthetic archwires differ from one another in terms of coating materials and thickness. The archwires were ligated and remained in-situ for eight weeks. After removal of the archwires, the tooth alignment, coating loss, colour change, and patient perception were assessed using Little's Irregularity Index, Autodesk® AutoCAD® software, Adobe® Photoshop®, and Oral Aesthetic Subjective Impact Scale (OASIS) questionnaire, respectively. Results: The analysis shows statistically significant differences between the four treatmen archwires for tooth alignment (p = 0.014), with RMO group showed the highest percentage (77.1%) and G&H group showed the lowest (63.7%). Orthocare archwires have the largest mean of colour change (11.11) and G&H the lowest value (9.01). In coating loss comparison, Orthocare group had the highest mean percentage of coating loss (33.4%) and RMO had the lowest (27.8%) despite no statistically significant difference (p = 0.137). Orthocare group had the highest percentage of positive perception (80.6%), whereas the RMO group showed the highest percentage of negative perception (33.3%). Conclusion: After the analysis it has been found out that there is significant tooth alignment, colour change, coating loss, and patient perception after the clinical use of aligning aesthetic archwires. The partially coated PTFE RMO group performed better than the other groups for both alignment reduction and coating loss, but it is the least acceptable to patients. Whilst the fully coated PTFE Orthocare group had the highest acceptable, but in same time had the highest mean percentage of coating loss and colour change over the eight weeks of clinical use. The lowest alignment reductions after treatment were for fully coating epoxy G&H aesthetic archwires group and the lowest mean value of colour change.
Maternal And Neonatal Characteristics In Fetal/neonatal Alloimmune Thrombocytopenia In National Blood Centre
(2021-05)
Nalliappan, Parameswari
Fetal/neonatal alloimmune thrombocytopenia (FNAIT) is an uncommon condition due to maternal alloimmunization of fetal platelet leading to thrombocytopenia in fetal and neonate. The aim of this study was to determine the incidence of FNAIT in Malaysia and the associated maternal and neonatal factors. Retrospective data analysis of matched, case control study (39 FNAIT cases and 39 randomly selected controls) from the year 2011 to 2019 at National Blood Centre, Malaysia. Maternal and neonatal characteristics were compared with controls. The incidence of FNAIT in Malaysia was 0.85 per 100 000 live births.Common anti-Human Platelet Antigen (-HPA) identified in this study were Anti-HPA-5b, Anti-HPA-3a and Anti-HPA-5a. Fifty-eight (58%) (p=0.012) of mothers were younger than 35 years old, of Malay ethnicity and multiparous. Malay mothers were 4.8 times more likely to develop FNAIT as compared to non-Malay. Neonatal onset of presentation, platelet count and blood group were not significantly different than in control group. The most significant factor associated with FNAIT was neonatal presentation. Symptomatic neonates were more likely to develop FNAIT. Incidence of FNAIT among Malaysians was lower than reported in the literature. Malay mothers and neonates presenting with symptoms are more likely to have FNAIT.
Red Blood Cells Transfusion Practice In Paediatric Cardiac Surgery At The National Heart Institute (Ijn) Of Malaysia
(2021-05)
Aizuddin, Maryam Jameelah
Introduction: Allogenic blood transfusion among paediatric cardiac surgery conducted under cardiopulmonary bypass (CPB) remains very frequent and is associated with potential adverse consequences, including postoperative morbidity. This study aims at identifying the predictive factors associated with perioperative red blood cells (RBC) transfusion and finding its association with postoperative outcomes, in order to promote patients' effective management and guide clinicians to decide on judicious blood transfusion. Methods: This cross-sectional retrospective study, conducted in IJN, involved 243 paediatric patients with cardiac surgery less than 18 years of age who had CPB surgery done in 2018. Results: Preoperatively, 4.5% of patients received RBC transfusion with significant predictor for transfusion; haemoglobin (Hb) with mean value of 8.3 to 9.8 g/dL. Intraoperatively, cumulative of 99.2% of patients received RBC transfusion with predictive factors for transfusion in high RBC transfusion subgroup; young age, low body weight, RACHS-1 scores of ≥ 3 and had longest CPB time compared to other groups. RBC transfusion status pre- and intraoperatively was found not to influence postoperative RBC transfusion status significantly. Our analysis showed that 25.9% of our studied population received low RBC transfusion during the postoperative period, while another 11.5% received high RBC transfusion. The CBP time and surgery duration were profoundly longer in the postoperative high RBC transfusion subgroup. Longest mechanical ventilation is significantly associated with preoperative low RBC transfusion subgroup and other covariates like lower body weight and longer CPB time. Longer duration of PICU stay was correlated with low preoperative and high postoperative RBC transfusion, lower body weight, RACSH-1 score >2 and longer CPB time duration. Conclusion: The predictive transfusion factors identified in relation to operative time were unique to each phase. This study also concluded that certain perioperative RBC transfusion status showed a significant association with selected postoperative outcomes, duration of mechanical ventilation and length of the PICU stay.
Day And Night Time Packed Red Blood Cells Transfusion Practice Among Adult Patients In Non-emergency Wards At Hospital Universiti Sains Malaysia (Husm) Kelantan
(2021-05)
Abdullah, Mohd Redzuan
Background: Most of the transfusion services have a policy of strongly discouraging blood administration at night unless for emergency cases. However, blood transfusion at night is still a common practice in most hospitals even in the non-emergency wards. Thus, this study aimed to audit the practice of PRBC transfusion and its compliance towards national transfusion guideline. Methods: This is a cross-sectional study involving a retrospective data collection of 385 adult inpatients who received PRBC transfusion in Hospital Universiti Sains Malaysia (HUSM) from 1st January 2017 to 31st December 2018. The selected patients were grouped into day and night time transfusion. Night time blood transfusion is defined as those who received PRBC between 8.00 pm to 8.00 am. Data for demographics, clinical characteristics, and three time intervals of transfusion process were collected from blood transfusion request form, MyTransfusi online system, and patient case note. Factors associated with night time blood transfusion were analysed using multiple logistic regression. Results: Total PRBC transfusion was 13,090 units. The prevalence of night time PRBC transfusion was 19.3% (2,523 units). Generally, female (56.2%), Malay (93.8%), bloop group O (35.7%), and from the medical discipline (28.6%) were the highest group of patients transfused at night. There were only 44 (39.3%) patients who received night time transfusion classified into acute clinical need group of transfusion indication. Most of the night time PRBC were transfused after 30 minutes issued by the blood transfusion service which were 70 patients (62.5%). Besides, 29 patients (25.9%) for night time group of patients received transfusion beyond four hours limit. Cryoprecipitate was 2.7 times more likely to be transfused at night (adjusted OR= 2.70; 95% CI= 1.04,7.01; P= 0.041). Adverse transfusion reaction was 7.1 times higher risk to develop at night (adjusted OR= 7.07; 95% CI= 1.26,39.71; P=0.026). Conclusion: Even though the practice of the night time PRBC transfusion was low, there was an increased in adverse transfusion reactions during this time and thus potentially increased morbidity and mortality of patients.
The Effectiveness Of Applied Muscle Tension In Reducing Vasovagal Reaction Among Young Blood Donors In Kelantan
(2021-05)
Alam Faizli, Afif
Background: The vasovagal reaction (VVR) incidence is the most common adverse donor reaction poses a major risk to the donor's safety and a disincentive for repeat donation. This study's main objective is to determine the efficacy of applied muscle tension (AMT) in reducing the VVR incidence among young blood donors in Kelantan. Methods: A prospective comparative interventional study was conducted among 306 young blood donors that were equally assigned to AMT and non-AMT groups. Donors were assessed with Blood Donation Reactions Inventory at 30 minutes and 48 hours post blood donation. The subjects will be followed-up on whether they make at least one donation attempt in the next six months. Results: Out of 306 young blood donors, the incidence of VVR was 24.8%. The AMT group showed a significant reduction in the VVR incidence rate compared to the non-AMT group (p<0.001). There was no significant increment of donor return rate among the AMT group than nonAMT group upon follow-up in six months. In addition, female (p=0.002), low body weight (p=0.002), low estimated blood volume (p=0.033) and low systolic blood pressure (p=0.005), are important predictors of VVR. Conclusions: This study showed that AMT was an effective strategy to reduce the VVR incidence among young blood donors in Kelantan. Implementation of AMT is recommended to donors with high risk of developing VVR
Knowledge Regarding Informed Consent For Blood Transfusion Among Patients In Hospital Melaka And Its Associated Factors.
(2021-05)
Senin @ Nordin, Mohd Hilmi
Background: To perform blood transfusion, a physician is required to obtain informed consent from the patient. However, previous studies have shown a poor transfer of knowledge from the doctor to the patient regarding blood transfusion, with conflicting information as recollected by patients from informed consent discussions. This study aims to evaluate knowledge on informed consent for blood transfusion among patients. Methods: A cross-sectional study was performed from October 2019 to May 2020 at Hospital Melaka. The instrument used in this study was a structured, validated questionnaire written in the Malaysian language. Respondents aged 18 and above, who had given their consent for blood transfusion within three days, were recruited using purposive sampling. Logistic regression was used to investigate potential predictors for good knowledge. Results: Data analysis was performed on 239 sets of returned questionnaires, which showed that 85.8% of the respondents had good knowledge. Additionally, 94.1% of them were aware that informed consent is mandatory before the blood transfusion procedure. The lowest percentage of correct responses (43.9%) was regarding the timing of the informed consent. Respondents with a history of undergoing transfusion more than once (AOR = 2.18; 95% CI = 1.02, 4.65; p = 0.04), and practising Buddhism as a religion (AOR = 0.36; 95% CI = 0.15–0.86; p = 0.02) showed significant associations with knowledge. Conclusion: The respondents in this study were relatively knowledgeable of informed consent for blood transfusion. However, further analysis revealed the deficiency of knowledge among the respondents in several aspects of this topic. The findings can aid Malaysian health authority to plan for interventions that would improve knowledge of informed consent on blood transfusion among patients and the public.
Parental Perception On Quality Of Life Of Their Children Following Dental Treatment Under General Anaesthesia
(2021-09)
Nadeem, Saman
General anaesthesia (GA) is extensively used to deliver safe and effective dental treatment for paediatric patients with physical, mental and medically compromising conditions who fail to respond to other behaviour modification techniques. This study's objective is to determine the importance and acceptance of general anaesthesia among parents whose child has undergone treatment under GA at Advanced Medical and Dental Institute, Universiti Sains Malaysia and the impact of treatment under GA has on their child’s Oral Health Quality of Life (OHQoL). Part 1 of this study, 113 records (October 2015 - February 2019) were retrived to find out the type of treatment performed and reasons for the treatment being provided under GA. Simultaneously, only 56 out of 113 parents from the record responded to answer parents' perception and satisfaction on dental treatment under GA using a questionnaire adapted from the Parents and Caregivers Perception Questionnaire (PCPQ) and Cleft Evaluation Profile (CEP). For part 2, it was pre and post-treatment study where 58 parents with children (March 2019 - December 2019) registered for their treatment under GA were requested to answer the same questionnaire as in Part 1. The results showed the main type of treatment performed was extractions of deciduous teeth (93.0%) and restoration using stainless steel crowns and Glass ionomer cement. The reasons for administering GA were total oral rehabilitation (72.5%) due to rampant caries, medical (18.7%) and behavioural problems (8.8%). The total mean(SD) score for P- CPQ was 57.44 (17.75), and for Facial Evaluation Profile was 17.44 (9.59). All the 56 parents (100%) were satisfied with the dental treatment under GA. For pre and post-treatment study, there is a significant difference between the mean score of P-CPQ pre-treatment and post-treatment for oral symptoms, functional limitation, emotional well-being, and social well-being with a P-value of 0.007, 0.006, 0.001 and 0.043, respectively. However, there is no significant difference in the facial evaluation profile with P=0.385. Oral rehabilitation was the reason of providing treatment under GA and SSC were used to protect posterior dentition, whereas GIC was the material of choice. Acceptance by parents on treatment under GA for children could be seen in this study with a positive effect on OHRQoL of their child. All the respondents reported satisfied with the dental treatment provided under GA. Generally, there was a significant improvement in the quality of life of the patient’s post-treatment. Further study with a larger number of subjects may give a more precise results
Synthesis, Characterization, And Cytotoxicity Evaluation Of Magnesium-doped Biphasic Calcium Phosphate (Mg-bcp) Powders
(2021-10)
Rama, Ballouze
Recently, bone and dental surgeries are becoming remarkably prevalent, and the natural bone grafts shortage in this area is evident. Thus, the need for synthetic bone graft substitutes is increasing. Synthetic calcium phosphates (CaPs) are ideal, resorbable, and biocompatible biomaterials that are almost identical to the mineral part of the bone and tooth enamel, especially when they are doped with different ions. Since magnesium ion (Mg) performs significant functions throughout the human body, Mg-doped biphasic calcium phosphate (Mg-BCP) gets special attention among other CaPs. Besides biocompatibility, osteoconductive, and osteoinductive properties, Mg-BCP has better mechanical properties. In this project, Mg-BCP powder with HA:βTCP ratio equals 60:40, and Mg substitution of 1 wt% was synthesized using the chemical wet precipitation method and characterized via XRD, SEM-EDX, and FT-IR techniques. After that, several doses (1 to 400 μg/mL) of MgBCP were co-cultured with hFOB 1.19 cells for 24, 48, and 72 h for in vitro cytotoxicity evaluation and microscopic observation. Additionally, alkaline phosphatase (ALP) activity of hFOB 1.19 cells was investigated after 72 h co-culture with 50 and 200 μg/mL doses of Mg-BCP. For all the experiments, pristine BCP was included for comparison purposes. As a result, Mg-BCP powder with the desired phase composition ratio (HA:βTCP = 60:40, 1 wt% Mg) was successfully synthesized as confirmed by XRD, FT-IR, and SEM-EDX analysis. Cytotoxicity evaluation indicated that Mg-BCP did cause a certain reduction in cell viability. However, the reduction was not severe even when hFOB 1.19 cells were co-cultured with the highest dose of the synthesized powder (400μg/mL) for the longest incubation period (72 h); the cell viability was above 83% with no changes in the cell morphology. Interestingly, the Mg-BCP powder was less toxic than BCP. Moreover, increasing the Mg-BCP dose significantly enhanced the ALP activity in hFOB 1.19 cells compared to BCP and untreated cells. In conclusion, the Mg-BCP powder with a phase composition ratio equals 60:40 and 1 wt% Mg is a promising bone graft substitute.
A Five Year (2013-2017) Retrospective Study On The Data Of Laboratory Testing For Biocompatibility Of Medical Device Implant Registered With Malaysia Medical Device Authority
(2021-11)
Sunthara Murthi A/L Anamalai
The study focused on the implantable medical devices which require most number of biocompatibility data. Data collection form reflecting the MeDC@St data entry pages is prepared to manually retrieve the deposited information for registration between July 2013 to December 2017, amounting to 1925 registration with some exceeds 100 pages content per registration.
Dual-thresholding based sinogram interpolation To reduce metal artefact In Computed tomography imaging
(2021-11)
Mohamad sobri, Nurul Fathin
Metal artefacts can degrade the image quality of computed tomography(CT)images which lead to difficulties and errors in diagnostic analysis. Metal artefactsappear as bright and dark streaks around the metal object. It is caused bybeamhardening effects, photons starvation, non-linear partial volume, photonscatter, undersampling and inappropriate correction algorithm during reconstructionofimage. The aim of this study is to improve the sinogram interpolation techniqueformetal artefacts reduction (MAR) in CT images. The MAR algorithmof this studywas developed using MATLAB platform. The first step of the algorithmwas theacquisition of virtual sinogram from the CT image using Radon transformfunction. Then, the thresholding technique is used to detect and isolate the metal part withinthe sinogram of the CT image. Two interpolation methods, cubic spline (CS) andLaplace interpolation (LI) were applied to replace the missing sinogramdata. Theinterpolated sinogram was then reconstructed using backprojection (byinverseRadon function) and finally the thresholded and interpolated images were fusedtoproduce corrected image. A total of seven phantom and six clinical CTimages withdifferent artefacts severity were selected for MAR correction. Qualitativeandquantitative evaluation of the corrected CT images was performed to evaluatetheeffectiveness of the proposed MAR technique. The findings showed metal artefact was significantly reduced by LI method (p-value = 0.02) as compared to CSmethod(p-value = 0.17). From quantitative analysis, the artefact index (AI) for LI-correctedimages is lower (mean AI = 66.07), but CS-corrected images yielded higher AI values (mean AI = 141.35) than the original images (mean AI = 99.31). The resultsfrom qualitative analysis showed LI-corrected images received higher scores (meanscore ± SD of 1.75 ± 1.22) from radiologist compared to original image (1.08±1.08)and CS-corrected images (1.33 ± 1.23). In conclusion, LI method workmoreeffectively in artefact reduction on both phantom and clinical images of different degrees of artefact severity.
The Efficacy Of Radiocolloid In Sentinel Lymph Node Biopsy In Early-stage Breast Cancer
(2021-11)
Bolhan, Hayatul Azuwa
Purpose: This study aims to evaluate the performance of radiocolloid, blue dye and combined method in sentinel lymph node biopsy in early breast carcinoma. Methods: One hundred seventy-two clinically node-negative, early-staged breast cancer patients who underwent SLNB with combined radiocolloid and blue dye were recruited. The numbers of hot node and blue node were analysed in all patients, all excised nodes and metastatic nodes patients, giving rise to the detection rate, metastatic rate and failure rate of combined method, radiocolloid and blue dye method. The association between the clinicopathological factors and the SLN detection was also analysed. Results: Out of 172 patients, the presence of a hot node and a blue node were 98.2% (169/172) and 95.9% (165/172) respectively. The overall SLN detection rate through combined method was 99.4% (171/172) and metastatic rate was 19.2% (33/172). Among the 33 metastatic-node patients, the combined method, radiocolloid and blue dye method failed to identify 1, 1 and 4 patients respectively. Therefore, the failure rate of the combined method, radiocolloid and blue dye method were 3.0% (1/33), 3.0% (1/33) and 12.1% (4/33), respectively. No significant finding was observed to associate clinicopathological factors and the SLN detection. Conclusion: This study showed the combined method of SLNB yielded the highest detection rate when compared to radiocolloid-alone and blue dye-alone method. More SLN was detected by radiocolloid method than blue dye method. Therefore, incorporating radiocolloid method in the blue dye method will improve SLN identification rate and reduce the failure rate of metastatic detection.

Browse

Browsing Institut Perubatan & Pergigian Termaju - Tesis by Issue Date

Results Per Page

Sort Options