31 research outputs found

    Mechanical properties of caco3 extracted from cockle shell with high density polyethylene (HDPE) for biomaterials in bone substitute application

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    This study was conducted to produce CaCO3 powder extracted from cockle shells as bioceramic materials which later combined with high density polyethylene (HDPE) as the polymer to produce composite as the final product. For CaCO3 clarification, the powder form of bioceramics was analyzed using FTIR, SEM and EDX analyses. Then, the composites produced were tested for mechanical properties via tensile and hardness tests. Firstly, the wasted cockle shells were all washed to remove dirts and soaked in regular water overnight before left to dry at room temperature. Then, they were all ground up between range 100 – 200 µm several times until the required size were obtained. The spectrum for FTIR showed identical result as previous work at reading 857.22cm-1 which represent vibrational bonds that can be attributed to the characteristics of external plane bending vibration of carbonate. After the confirmation, it was added to the melted HDPE to produce stronger composite via injection moulding method. Injection moulding process was to produce the sample into the shape of dumbbell to perform mechanical tests, tensile and hardness test with three parameters for each weight ratio. It could be concluded that pressure, velocity and temperature affecting the hardness of samples. In this research, the greatest value of Young’s modulus and maximum force which are 852.2 MPa and 271.457 kN, respectively. In conclusion, cockle shell could become great biomaterial as it provide good in mechanical properties. Furthermore, the source also abundantly available and with the fully usage of this waste to something more useful, it is able to reduce contamination to the earth. Then, the combination with any polymer is able to produce strong composite that could apply in any field. For this research, the composite is focus in biomaterial usage, especially in orthopaedic field for bone implant. For instance, CaCO3 are proved to be function at higher temperature, and further future works might be required to search the maximum temperature that this material could achieve

    Exsolution enhancement of metal-support co oxidation perovskite catalyst with parameter modification

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    This study aimed to further tune the capability of active metal exsolution onto the surface of the CO oxidative perovskite catalyst La0.7Ce0.1Co0.3Ni0.1Ti0.6O3 by tuning the reducing parameter. Under same calcination temperature of 800℃, XRD analysis shown that the precursors with calcination duration of 6 hours (S2T8H6) was able to achieve similar crystalline structure to those with calcination duration of 12 hours (S2T8H12). In order for the active metal (CoNi) to be exsolved onto the perovskite surface, reducing parameter such as temperature and duration are deemed crucial to the reduction process. The exsolution of the active metals was observed when the samples were treated under reducing condition with varying temperatures of 550℃ and 700℃ and duration from 200 to 300 minutes. Through comparison with their EDX readings, S2T8H6 treated under 700℃ and 300 minutes (S2T8H6-R7H5) achieved the highest weight percentage of surface Cobalt and Nickel of 3.83 and 2.81. It was clear that by tuning the temperature and duration of reduction, the exsolution of the active metals onto the surface of the perovskite could be improved resulting in better exposure and dispersion of active metals onto the surface of catalyst

    A whole genome analyses of genetic variants in two Kelantan Malay individuals

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    The sequencing of two members of the Royal Kelantan Malay family genomes will provide insights on the Kelantan Malay whole genome sequences. The two Kelantan Malay genomes were analyzed for the SNP markers associated with thalassemia and Helicobacter pylori infection. Helicobacter pylori infection was reported to be low prevalence in the north-east as compared to the west coast of the Peninsular Malaysia and beta-thalassemia was known to be one of the most common inherited and genetic disorder in Malaysia.By combining SNP information from literatures, GWAS study and NCBI ClinVar, 18 unique SNPs were selected for further analysis. From these 18 SNPs, 10 SNPs came from previous study of Helicobacter pylori infection among Malay patients, 6 SNPs were from NCBI ClinVar and 2 SNPs from GWAS studies. The analysis reveals that both Royal Kelantan Malay genomes shared all the 10 SNPs identified by Maran (Single Nucleotide Polymorphims (SNPs) genotypic profiling of Malay patients with and without Helicobacter pylori infection in Kelantan, 2011) and one SNP from GWAS study. In addition, the analysis also reveals that both Royal Kelantan Malay genomes shared 3 SNP markers; HBG1 (rs1061234), HBB (rs1609812) and BCL11A (rs766432) where all three markers were associated with beta-thalassemia.Our findings suggest that the Royal Kelantan Malays carry the SNPs which are associated with protection to Helicobacter pylori infection. In addition they also carry SNPs which are associated with beta-thalassemia. These findings are in line with the findings by other researchers who conducted studies on thalassemia and Helicobacter pylori infection in the non-royal Malay population.Wan Khairunnisa Wan Juhari, Nur Aida Md Tamrin, Mohd Hanif Ridzuan Mat Daud, Hatin Wan Isa, Nurfazreen Mohd Nasir, Sathiya Maran, Nur Shafawati Abdul Rajab, Khairul Bariah Ahmad Amin Noordin, Nik Norliza Nik Hassan, Rick Tearle, Rozaimi Razali, Amir Feisal Merican and Bin Alwi Zilfali

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

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    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    Targeted agents and immunotherapies: optimizing outcomes in melanoma

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    Treatment options for patients with metastatic melanoma, and especially BRAF-mutant melanoma, have changed dramatically in the past 5 years, with the FDA approval of eight new therapeutic agents. During this period, the treatment paradigm for BRAF-mutant disease has evolved rapidly: the standard-of-care BRAF-targeted approach has shifted from single-agent BRAF inhibition to combination therapy with a BRAF and a MEK inhibitor. Concurrently, immunotherapy has transitioned from cytokine-based treatment to antibody-mediated blockade of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and, now, the programmed cell-death protein 1 (PD-1) immune checkpoints. These changes in the treatment landscape have dramatically improved patient outcomes, with the median overall survival of patients with advanced-stage melanoma increasing from approximately 9 months before 2011 to at least 2 years - and probably longer for those with BRAF-V600-mutant disease. Herein, we review the clinical trial data that established the standard-of-care treatment approaches for advanced-stage melanoma. Mechanisms of resistance and biomarkers of response to BRAF-targeted treatments and immunotherapies are discussed, and the contrasting clinical benefits and limitations of these therapies are explored. We summarize the state of the field and outline a rational approach to frontline-treatment selection for each individual patient with BRAF-mutant melanoma

    31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

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    Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

    Simulation of the Corrosion Point and Repairing Technique at the Crane with Finite Element Analysis

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    This paper describes the stress analysis for the corrosion area at the hollow pipe crane structure. This crane is used for lifting the load. Finite element analysis was used to, investigate the stress concentration at the corrosion point. Three stages had been simulated; first stage simulates the structure without corrosion, second stage simulates the main chord with corrosion and third stage simulates the corrosion point with patch method and clamp shell repair method. The results show that the stress concentrations at the corrosion points were double from the normal point. Clamp shell method reduces the stresses by 28.6%. This technique saves the costs and time to repair the corrosion areas
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