Showing papers by "Ahmad Sukari Halim published in 2017"

Mechanism Action of Platelets and Crucial Blood Coagulation Pathways in Hemostasis.

Abstract: Blood is considered to be precious because it is the basic necessity for health; our body needs a steady provision of oxygen, supplied via blood, to reach billions of tissues and cells. Hematopoiesis is the process that generates blood cells of all lineages. However, platelets are the smallest blood component produced from the very large bone marrow cells called megakaryocytes and they play a fundamental role in thrombosis and hemostasis. Platelets contribute their hemostatic capacity via adhesion, activation and aggregation, which are triggered upon tissue injury, and these actions stimulate the coagulation factors and other mediators to achieve hemostasis. In addition, these coordinated series of events are the vital biological processes for wound healing phases. The aim of this review is to summarize and highlight the important pathways involved in achieving hemostasis that are ruled by platelets. In addition, this review also describes the mechanism action of platelets, including adhesion, activation, aggregation, and coagulation, as well as the factors that aid in hemostasis and wound healing.

Prognostic factors and survival rate of osteosarcoma: A single-institution study.

Abstract: Aim Osteosarcoma is a highly malignant primary bone tumor. The study aim to evaluate the prognostic factors influencing the survival rate in our center. Methods This was a retrospective cohort study of all patients treated between January 2005 and December 2010. Results We included 163 patients with an age range of 6–59 years (median = 19). The median follow-up was 47 months (range 36–84). The overall survival in patients who completed chemotherapy and surgery (n = 117) was 72% at 2 years and 44% at 5 years. Histologically, 99 (85%) had osteoblastic, 6 (5%) had chondroblastic and 3 (2.5%) had telangiectatic osteosarcoma. Limb salvage surgery was performed in 80 (49%) and 41 (25%) underwent amputation. However, 46 patients (28%) underwent no surgical intervention and incomplete chemotherapy. In total, 38/79 patients had a good chemotherapy response. There was a significantly better survival rate for limb salvage versus amputation. Independent prognostic factors for survival are compliance to treatment and presence of lung metastasis. Conclusion The overall survival of osteosarcoma patients was influenced by the presence of pulmonary metastases and compliance to treatment. Histological subtype, different chemotherapy regimens and histological necrosis after chemotherapy did not significantly influence survival. The patients who did not complete treatment had significantly poorer survival.

Proliferation and Differentiation of Human Hair Follicle Stem Cells on Chitosan-Skin Engineered Template in Vitro

Abstract: Hair follicles repeatedly regress and reconstitute themselves, suggesting the presence of intrinsic tissue stem cells. Among the unique characteristics of adult stem cells isolated from hair follicles is their ability to differentiate into keratinocytes. Study on chitosan skin-engineered templates (SETs) as scaffolds for the proliferation of human fibroblasts have shown the promise of SETs in facilitating skin cell growth in three-dimensional culture. High proliferation in three-dimensional culture using human cells allows the researcher to extensively evaluate the cultivation of desirable cell types on chitosan SETs. Therefore, this study aimed to evaluate the in vitro attachment, proliferation and differentiation of hair follicle stem cells (HFSCs) on a chitosan SETs. HFSCs were isolated from human scalp tissues using collagenase type I prior to propagation in supplemented CnT-07 media. The phenotype of the HFSCs was verified using the markers keratin-15 (K15) and CD200, as detected by immunocytochemical staining. The attachment and proliferation of the HFSCs on the chitosan SETs were evaluated using scanning electron microscopy (SEM), an alamar blue assay and a live/dead assay. Subsequently, the HFSCs were differentiated using CnT-2D differentiation media. The cells’ differentiation was verified using the markers involucrin and keratin-6 (K6), as detected by immunofluorescence staining. The HFSCs were successfully isolated, proliferated and differentiated according to staining positivity and microscopy imaging. HFSCs are able to proliferate and directly differentiate into keratinocytes on a chitosan SETs, which may facilitate their use in regenerative medicine.

Linkage evidence and methylation at 2q region in nonsyndromic cleft lip and/or palate of Malay population

Abstract: Introduction: Nonsyndromic cleft lip and/or palate (NSCLP) occurs as a result of multifactorial determinants, involving both genetic and environmental factors. Several candidate genes associated with NSCLP have been discovered through genetic approach, but there is paucity of studies focusing on epigenetic determinants in NSCLP. We are interested to reveal linkage evidence of SATB2 at 2q region in large-extended NSCLP families of Malay population and its methylation activity in causing cleft formation. Materials and Methods: Eight large-extended families were included in this study. Microarray analysis was carried out and genome-wide linkage was determined using GeneHunter Multipoint Linkage Analysis v2.1r5. SATB2 methylation was tested on 100 NSCLP patients by DNA sequencing. Results: Genome-wide linkage analysis has revealed significant nonparametric linkage score and suggestive logarithm of the odds (LOD) score at 2q region in family 50 and family 100. Genome-wide heterogeneity LOD score of 2.63 and α =0.122 were found in total families at 2q33.1-q35 region. Significant copy number loss (P < 0.05) in NSCLP family compared with the normal control supports the linkage evidence of SATB2 in those families with positive linkage. Epigenetic testing found SATB2 unmethylation at DNA promoter region. Discussion: Linkage evidence and significant low copy number of SATB2 in NSCLP family of Malay population confirmed that genetic factors play a major role in causing cleft defects. SATB2 unmethylation could not support the epigenetic occurrence in causing craniofacial deformities. Conclusions: Linkage evidence and significant low copy number of SATB2 in NSCLP family of Malay population confirmed that genetic factors play a major role in causing cleft defects. SATB2 unmethylation could not support the epigenetic occurrence in causing craniofacial deformities.

The Effects of Passive Cigarette Smoke Exposure on the Survival of the Reverse Sural Fasciocutaneous Flap.

Abstract: Background The possibility of a person who had undergone surgery to be exposed to the ill effects of cigarette smoke is high, more so if the person lives with a smoker. With increasing popularity of reverse sural fasciocutaneous flaps, a surgeon may have to manage a person who lives with a smoker or is exposed to cigarette smoke. A clear understanding of the effects of exposure to cigarette smoke on reverse sural fasciocutaneous flaps is necessary. This study was performed to establish a clearer understanding of the effects of smoking on reverse sural fasciocutaneous flaps and evidence for preoperative patient counseling about smoking and smoke exposure. Objective The study investigated effects of exposure to cigarette smoke on the survival of the reverse sural fasciocutaneous flap. Methods This was an experimental observational study conducted at the Laboratory for Animal Research Unit in the Health Campus of Universiti Sains Malaysia. Twelve adult White New Zealand rabbits ( Oryctolagus cuniculus ) were divided into two groups of six. All 12 rabbits had a 2.5- × 2.5-cm reverse sural fasciocutaneous flap raised on both its hind limbs. The group exposed to cigarette smoke underwent 4 weeks of smoke exposure for 2 hours daily prior to surgery. This was then continued until analysis of the results. The control group had no intervention. All flaps were analyzed on the seventh postoperative day, after tracing on transparent plastic sheets with the necrotic area marked followed by 2D planimetry done on a grid paper. The flaps were assessed on the total flap area and survival area percentage. It was recorded as mean ± SD. The presence or absence of infection and hematoma was also noted. Results Twelve flaps were analyzed in each group. Total mean flap area and survival area percentage of the control group were 120.33 ± 31.03 mm 2 and 80.12 ± 15.75%, respectively, whereas in the cigarette smoke–exposed group, it was 121.83 ± 17.93 mm 2 and 62.04 ± 34.01%, respectively. The control group had two infections and one hematoma, and the smoking-exposed group had six infections and nine hematomas. The comparison between the groups was made in terms of total flap area, survival percentage, presence of infection, and hematoma for which the p values were 0.886, 0.115, 0.083, and 0.003, respectively. The differences between right and left hind limbs were also analyzed ( p = 0.414). Conclusion There was no statistical difference in the results from the right and left hind limbs. There was no statistical difference in the survival of reverse sural fasciocutaneous flap between the control and smoking-exposed groups.