1.Development of a purification method of pure primary lymphocytes for cell viability assays.
Chan Kok Keong ; Vishna Devi V Nadarajah * ; Tay Ju Lee
Malaysian Journal of Medical Sciences 2007;14(1):38-45
The maintenance of pure primary lymphocytes culture for long periods may be difficult because of its inability to divide continuously. In addition, lymphocytes separation methods such as Ficoll-Paque, RBC lysis and immunomagnetic microbeads separation may have some affect on cell viability. The objective of this study is to determine various types of lymphocytes purification methods, in order to prolong primary lymphocytes culture to 72 hours. The second objective is to use these primary lymphocytes as targets for quantitative and qualitative cell viability assays when analysing the action of toxins isolated from natural products. Human blood was drawn and purified by using Ficoll-Paque, RBC lysis or
immunomagnetic separation column method in various combinations. The purified lymphocytes were also grown with and without the growth enhancement factor, concanavalin-A. Cell viability assays were carried out for 72 hours at 24 hours interval. The lymphocytes purified using RBC lysis method, with or without concanavalin-A can prolong 100% cell viability for 72 hours whilst lymphocytes purified using Ficoll-Paque and supplemented with concanavalin-A showed an increase in cell viability of over 250% at 72 hours incubation. It was observed only lymphocytes purified using Ficoll-Paque followed by the immunomagnetic microbeads separation method and supplemented with concanavalin-A showed overall cell viability increase, reaching 300% at 72 hours incubation. This method was a reliable model to test the cytotoxicity of the Bacillus thuringiensis parasporal inclusion, suggesting that the method achieves the objectives of the study.
3.Neuropathic Pain after Adolescent Idiopathic Scoliosis Correction Surgery
Mohd Shahnaz HASAN ; Khean Jin GOH ; Hing Wa YIP ; Siti Mariam MOHAMAD ; Teik Seng CHAN ; Kok Ian CHONG ; Amber HASEEB ; Chee Kidd CHIU ; Chris Chan Yin WEI ; Mun Keong KWAN
Asian Spine Journal 2021;15(5):628-635
Methods:
Forty AIS patients were recruited. Demographic, preoperative, and postoperative data were recorded. The magnitude and characteristics of postoperative pain were assessed using the painDETECT questionnaire through telephone enquiries at intervals of 2, 6, 12, and 24 weeks. Statistical analyses were followed by Pearson correlation test to determine the relationship between pain scores at 6, 12, and 24 weeks with the risk factors.
Results:
Based on the painDETECT questionnaire, 90% of the patients had nociceptive pain, and 10% had a possible neuropathic pain component at 2 weeks postoperatively as per a mean painDETECT score of 7.1±4.5. Assessments at 6, 12, and 24 weeks showed that no patients had neuropathic pain with painDETECT scores of 4.4±3.2, 2.9±2.9, and 1.5±2.0, respectively. There was a significant correlation between total postoperative morphine use during 48 hours after the surgery and a tendency to develop neuropathic pain (p=0.022).
Conclusions
Chronic neuropathic pain was uncommon in AIS patients who had undergone PSF surgery. Higher opioid consumption will increase the possibility of developing chronic neuropathic pain.
4.The anatomical locations of postoperative pain and their recovery trajectories following Posterior Spinal Fusion (PSF) surgery in Adolescent Idiopathic Scoliosis (AIS) patients
Chee Kidd Chiu ; Kok Ian Chong ; Teik Seng Chan ; Siti Mariam Mohamad ; Mohd Shahnaz Hasan ; Chris Yin Wei Chan ; Mun Keong Kwan
The Medical Journal of Malaysia 2020;75(1):12-17
Introduction: This study looked into the different anatomical
locations of pain and their trajectories within the first two
weeks after Posterior Spinal Fusion (PSF) surgery for
Adolescent Idiopathic Scoliosis (AIS).
Methods: We prospectively recruited patients with
Adolescent Idiopathic Scoliosis (AIS) scheduled for PSF
surgery. The anatomical locations of pain were divided into
four: (1) surgical wound pain; (2) shoulder pain; (3) neck
pain; and (4) low back pain. The anatomical locations of pain
were charted using the visual analogue pain score at
intervals of 12, 24, 36, 48 hours; and from day-3 to -14.
Patient-controlled analgesia (morphine), use of celecoxib
capsules, acetaminophen tablets and oxycodone
hydrochloride capsule consumption were recorded.
Results: A total of 40 patients were recruited. Patients
complained of surgical wound pain score of 6.2±2.1 after
surgery. This subsequently reduced to 4.2±2.0 by day-4, and
to 2.4±1.3 by day-7. Shoulder pain scores of symptomatic
patients peaked to 4.2±2.7 at 24 hours and 36 hours which
then reduced to 1.8±1.1 by day-8. Neck pain scores of
symptomatic patients reduced from 4.2±1.9 at 12 hours to
1.8±1.1 by day-4. Low back pain scores of symptomatic
patients reduced from 5.3±2.3 at 12 hours to 1.8±1.1 by day12.
Conclusions: Despite the presence of different anatomical
locations of pain after surgery, surgical wound was the most
significant pain and other anatomical locations of pain were
generally mild. Surgical wound pain reduced to a tolerable
level by day-4 when patients can then be comfortably
discharged. This finding provides useful information for
clinicians, patients and their caregivers.
5.Mid-term study of transcatheter aortic valve implantation in an Asian population with severe aortic stenosis: two-year Valve Academic Research Consortium-2 outcomes.
Nicholas CHEW ; Jimmy Kim Fatt HON ; Wei Luen James YIP ; Siew Pang CHAN ; Kian-Keong POH ; William Kok-Fai KONG ; Kristine Leok Kheng TEOH ; Tiong Cheng YEO ; Huay Cheem TAN ; Edgar Lik Wui TAY
Singapore medical journal 2017;58(9):543-550
INTRODUCTIONTranscatheter aortic valve implantation (TAVI) is an effective treatment for high-risk or inoperative patients with severe aortic stenosis. Given the unique characteristics of Asian populations, questions regarding mid-term outcomes in Asians undergoing TAVI have yet to be addressed. We evaluated the two-year clinical outcomes of TAVI in an Asian population using Valve Academic Research Consortium-2 definitions.
METHODSThis prospective study recruited 59 patients from a major academic medical centre in Singapore. The main outcomes were two-year survival rates, peri-procedural complications, symptom improvement, valvular function and assessment of learning curve.
RESULTSMean age was 76.8 years (61.0% male), mean body surface area 1.6 mand mean logistic EuroSCORE 18.7%. Survival was 93.2%, 86.0% and 79.1% at 30 days, one year and two years, respectively. At 30 days post TAVI, the rate of stroke was 1.7%, life-threatening bleeding 5.1%, acute kidney injury 25.0%, major vascular complication 5.1%, and new permanent pacemaker implantation 6.8%. 29.3% of TAVI patients were rehospitalised (47.1% cardiovascular-related) within one year. These composite outcomes were measured: device success (93.2%); early safety (79.7%); clinical efficacy (66.1%); and time-related valve safety (84.7%). Univariate analysis found these predictors of two-year all-cause mortality: logistic EuroSCORE (hazard ratio [HR] 1.07; p < 0.001); baseline estimated glomerular filtration rate (HR 0.97; p = 0.048); and acute kidney injury (HR 5.33; p = 0.022). Multivariate analysis identified non-transfemoral TAVI as a predictor of cardiovascular-related two-year mortality (HR 14.64; p = 0.008).
CONCLUSIONDespite the unique clinical differences in Asian populations, this registry demonstrated favourable mid-term clinical and safety outcomes in Asians undergoing TAVI.