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- PublicationAnalysis And Production Of Artemisinin, An Antimalarial From Artemisia Annua L(1996)Artemisia amma derived from a heterogeneous seed population obtained from north viet nam, grew well in the local climate but did not produce seeds upon flowering. The plant was successfully propagated using a tissue culture technique. The artemisinin content varied among the plantlets. The plantiets were selected and cloned to give 3 major yielding lines of high, moderate and low artemisinin content. The high yielding plantlets, were found to have a mean artemisinin content of 0.41 % ± 0.02 sd, the moderate yielders, a mean arternisinin content of 0.25 % ± 0.02 sd, whereas the low yielders, a mean artemisinin content of 0.13 % ± 0.03 sd. Low and high yielding plants in the field contained a mean artemisinin content of 0.13 % ± 0.0 l sd and 0.33 % ± 0.01 sd, respectively. A high performance liquid chromatography method with electrochemical detection using a glassy carbon electrode was developed and was found to be sensitive and selective for the detection of artemisinin in plasma. The mean recovery values of arternisinin from the extraction, over a range of 25-800 ng ml-l were 88.86-97.68 % with a coefficient variation of 1.57-9.31 % (n=6). The detection limit was 12.5 ng ml-l for artemisinin at a signal to noise ratio of 5: 1.
- PublicationLiquid Crystalline Polimers : Studies On Bisphenol, Hydroquinone And 1,4-Cyclohexanediol Based Thermotropic Main Chain Liquid Crystalline Polyesters(1996)Three types of main chain moiety liquid crystal polyesters, poly(phenyleneterephthalate) (ppt), poly(bisphenol-terephthalate) (pba) and poly(i,4- cyclohexanediol-terephthalate) (pcy) were synthesised using acidolysis melt condensation method. In this project, ppt was used as a control for comparison. The reactivity of hydroquinone (hq), bisphenol a (ba) and 1,4-cycohexanediol (cy) towards terephthanoyl chloride (tci) were analysed by differential scanning calorimeter (dsc). It was found that the reaction of hq and tci was the fastest while ba was the slowest among the three diols. In addition, a series of copolyesters with different ratio of hq : ba were synthesised to study the effects of flexible ba content in ppt system. The properties of synthesised polyesters were characterised in terms of their solubility and thermal stability. Thermal and liquid crystalline properties were characterised by dsc and x-ray diffraction (xrd) method. Morphology of the crude and annealed (420°c) samples were observed by using scanning electron microscope (sem). Fourier transform infrared (ftir) was done to confirm the presence of polyesters and the ratio of hqfba in the copolyesters.
- PublicationQuadriceps femoris ultrasonography: A tool to assess nutritional status and prognosticate mortality outcome in adult mechanically ventilated patients(2022)Background: Inadequate nutritional therapy in enterally fed intensive care unit patients remains a global issue, as these patients possess higher nutrition risk. These high nutritional risk patients have significant muscle loss; thus, bedside muscle ultrasound is used to assess nutritional status through their percentage of skeletal muscle thickness (quadriceps femoris) decline whereby their adverse outcome is predicted. Methods: A prospective cohort study from May 2020 until June 2021 was conducted in Hospital Universiti Sains Malaysia, whereby 60 patients were recruited, and their blood parameters, skeletal muscle thickness and nutritional intake measurement were followed through during their ICU stay. The adverse outcome such as duration of mechanically ventilated days, hospitalisation days and mortality were recorded. The percentage decline of quadriceps femoris thickness is then used to prognosticate mortality. Results: Overall, the recruited patients are aged 50 years and above had mean APACHE II score 13, SOFA score 8, Charlson Comorbidity Index score 3.3, and the average score for mNUTRIC score is 3.6. This study revealed that 85% of our patients received optimal nutritional delivery by an average of 2.6 days. 36.7% of these patients are high nutritional risk (HNR) patients, but there is no statistically significant correlation with mortality. Nevertheless, the HNR patients have a greater percentage of skeletal muscle thickness decline and as early as Day 5, with a cut-off point of ≥7.80% decline can predict mortality. When comparing the degree of decrement throughout an ICU stay, the vastus intermedius exhibits a substantially higher rate of decline as early as day three. Conclusion: Ultrasonography of quadriceps femoris is a dynamic tool used to assess the nutritional status and predicting mortality as early as day 5 of admission. Serial scanning of quadriceps femoris prompts the physician for earlier method for nutritional optimization, early muscle rehabilitation and patient mobility which may reduce the morbidity and mortality of these patients.
- PublicationElagolix treatment in women with heavy menstrual bleeding associated with uterine fibroid: A systematic review and meta-analysis(2022)Background: Elagolix is effective and safe for treating menorrhagia in women with uterine fibroid. However, it is reported to be associated with hypoestrogenism that can be alleviated by adding estradiol/norethindrone acetate. This systematic review and meta-analysis aimed to determine the effectiveness of elagolix treatment in women with heavy menstrual bleeding associated with uterine fibroid by comparing elagolix versus placebo and elagolix versus estradiol/norethindrone acetate. Methodology: The Cochrane Central Register of Controlled Trials (CENTRAL 2021, Issue 3 of 12), MEDLINE databases (1980 to December week 1, 2020), and trial registries for relevant randomized clinical trials were used. All randomized clinical trials were reviewed and evaluated. Random effects models were used to estimate the dichotomous outcomes and mean differences with 95% confidence intervals. Data for risk of bias, heterogeneity, sensitivity, reporting bias and quality of evidence were assessed. Results: Four randomized controlled trials with 1949 premenopausal women from 323 locations were included. Elagolix improved menstrual blood loss of less than 80 ml (RR 4.81, 95% CI 2.45 to 9.45; four trials, 869 participants; moderate quality evidence) or more than 50% reduction from baseline (RR 4.87, 95% CI 2.55 to 9.31; four trials, 869 participants; moderate quality evidence) compared to placebo. There was no difference in menstrual blood loss of less than 80 ml (RR 1.08, 95% CI 1.00 to 1.16; five trials, 1365 participants; moderate quality evidence) or more than 50% reduction from baseline between the elagolix (RR 1.08, 95% CI 1.01 to 1.15; five trials, 1365 participants; high quality evidence) and elagolix with estradiol/norethindrone acetate. In both comparisons, elagolix has reduced the mean percentage change in uterine and fibroid volume, improved symptoms, and health-related quality of life. More patients had hot flush, and bone mineral density loss in the elagolix treatment compared to both placebo and elagolix with estradiol/norethindrone acetate. Conclusions: Elagolix appeared to be effective in reducing heavy menstrual bleeding caused by uterine fibroid and combination with estradiol/norethindrone acetate was able to alleviate the hypoestrogenism side effects in premenopausal women.
- PublicationA 3-year review of group-b streptococcus colonization in pregnancy and its perinatal outcome in Hospital Selayang(2022)INTRODUCTION AND OBJECTIVE: There is an increase in the prevalence of GBS infection in pregnancy, which causes significant morbidity and mortality to both mother and baby. This retrospective study will evaluate the impact and outcome of pregnancy associated with GBS in Selayang Hospital from year 2017 till 2019. STUDY METHOD: This retrospective study was performed at Hospital Selayang over a three-year period between 1st January 2017 and 31st December 2019. Patients with GBS colonization were identified from their case note and laboratory investigation result. Those patients who had their high vaginal swab culture growing GBS bacteria were considered as patient with GBS colonization. Patient’s demographic, obstetric and neonatal data were documented in Performa (Appendix 1). Data analysis was carried out with SPSS version 26.0. RESULTS: A total of 31762 patients delivered at Hospital Selayang. From this a total of 344 patients were noted to have GBS colonization, making its prevalence of 1.09%. Out of 344 deliveries, 114 of babies were admitted to NICU for various reason. Majority (56.3%) of them were admitted in view of presumed sepsis as the infants showed early sign of infection. From our study noted, that Chinese mothers has a significant association and 1.92 likelihood of baby admitted to NICU compared to other ethnicity (Adj 95% CI (1.11, 3.30), p =0.02) when antibiotic variable was controlled. Meanwhile patients who were given antibiotics has 0.62 reduce likelihood of baby admitted to NICU compared to patients who did not receive intrapartum antibiotic prophylaxis (p = 0.004). CONCLUSION: The prevalence (1.09%) shown much lower than other literature review, as the sample size not as universal screening in general population of pregnant patients. Only those patients who came with excessive vaginal discharge, PROM, PPROM and preterm labour were screened. There is significant association between Chinese ethnicity and NICU admission. It shown that babies born to Chinese mothers with GBS infection more prone to get admitted to NICU compare to other race and foreigners.
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- ItemChromaticity of bipartite graphs with three and four edges deleted(2007)Graphs are a set of vertices and edges. All vertices may or may not be joint. Vertex coloring is the coloring of a graph with a fixed number of colors such that adjacent vertices are of different colors. Considering all the possible ways of coloring a certain graph G with A colors will result in a polynomial in A. This polynomial is the chromatic polynomial of the graph G denoted by P (G; A). Two members from a set of graphs may have the same chromatic polynomial. These are called chromatically equivalent graphs. If a member of a set of graphs has a chromatic polynomial which is different from every other member in the set then this graph is chromatically unique. Bipartite graphs are graphs in which the vertices are partitioned into two non intersecting sets with condition that no vertices within the sets are adjacent. A complete bipartite graph is a bipartite graph with all the vertices in each set being adjacent to all the vertices of the other set. This project studies the chromaticity of complete bipartite graphs with three and also four edges deleted.
- ItemPer-Priority Flow Control (Ppfc) Framework For Enhancing Qos In Metro Ethernet(Universiti Sains Malaysia, 2013-11)Day by day Internet communication and services are experiencing an increase in variety and quantity in their capacity and demand. Thus, making traffic management and quality of service (QoS) approaches for optimization of the Internet become a challenging area of research; meanwhile flow control and congestion control will be considered as significant fundamentals for the traffic control especially on the high speed Metro Ethernet. IEEE had standardized a method (IEEE 802.3x standard), which provides Ethernet Flow Control (EFC) using PAUSE frames as MAC control frames in the data link layer, to enable or disable data frame transmission. With the initiation of Metro Carrier Ethernet, the conventional ON/OFF IEEE 802.3x approach may no longer be sufficient. Therefore, a new architecture and mechanism that offer more flexible and efficient flow and congestion control, as well as better QoS provisioning is now necessary.
- PublicationBzd9l1: Elucidation Of Its Anti-angiogenic Potential In In-vitro And In-vivo Colorectal Cancer Models(2023-09)Colorectal cancer (CRC) is the third most common cancer globally. CRC depends largely on angiogenesis for growth and metastasis. Much effort has been made to selectively target the angiogenic pathways to restrain tumour growth. However, some CRC patients become resilient to these anti-angiogenic drugs and standard therapies. The class III histone deacetylase family of sirtuins (SIRTs) has been closely linked to cancer progression but less is known about its activity in regulating tumour angiogenesis. BZD9L1 is a novel sirtuin inhibitor with demonstrated anti-cancer activities. This study aimed to investigate the anti-angiogenic potential of BZD9L1 on EA.hy926 endothelial cells (EC) in vitro and HCT116 tumour xenograft nude mice. The in vitro experiments comprised of cell viability assay, scratch wound assay, tube formation assay, spheroid sprouting assay, western blotting, angiogenesis array, cell cycle and apoptosis analysis via flow cytometry and finally, indirect co-culture model. Nude mice tumour xenograft model was used for the in vivo study, where hematoxylin and eosin staining was done to study the percentage of necrosis in the tumour section and immunohistochemistry was conducted to investigate the protein expression of Ki67 and CD34. BZD9L1 was shown to reduce cell viability, cell migration, tube formation, and spheroid sprouting of EC. BZD9L1 at 10μM was also shown to inhibit SIRT2 and SIRT3 protein in EA.hy926 cells. Angiogenesis array results revealed that the compound reduces the cytokine concentration of Angiogenin, bFGF, PDGF-BB, and PIGF significantly (P * < 0.05) compared to the control group
- ItemImproving The Traditional Method Of Producing Parboiled Rice(1977-03)A problem in the preparation of parboiled r1ce by a traditional method as carried out in one of the r1ce mills in Kedah 1S that the operation is rather time - consuming. This 1S especially attributed to the long soaking time employed (about 3 days). Apart from this, it produces a rather smelly product unacceptable to many people. The aim of the project was to investigate various ways of improving the method, By a water-absorption procedure, it ~as found. that for the variety of padi used. Mat can~u it took only about 15 hours soaking at ambient pressure and temperature for water to reach the centre of the grain. A relatively satisfactory parboiled rice was prepared by only 15 hours soaking. Another attempt was the use of benzoic acid to inhibit putrefactive changes during prolonged cold soaking. It was found that the use of a rather low level of benzoic acid in the soaking water (800 p.p.m.) could prevent putrefaction for at least 3 days. All preparations of parboiled rice were followed by analyses to ascertain the quality of the products. These included milling tests, chemical analysis for the B vitamins (B l and B 2 ) as well as evaluation of the cooked rice. Various aspects of the complications that may arise in the implementation of the findings on a large scale processing are also discussed.
- PublicationDecision Orientation Of Ceo Education And Its Effect On Risk-Taking: The Moderating Effect Of Economic Policy Uncertainty(2025-02)This thesis aims to examine the effect of a chief executive officer’s (ceo’s) decision orientation on corporate risk-taking, using data from 3,927 publicly listed companies on the malaysia stock exchange from 2015 to 2021. Our research focuses on how different decision orientation, logical and intuitive affect firm risk-taking. Our hypothesis suggests that ceos with a logical decision orientation are likely to engage in higher risk-taking, driven by confidence backed from a structured and analytical approaches. However, the empirical results indicate otherwise, showing that logical ceos are actually less inclined to take significant risks, a trend that holds across most of the variables assessed. A further academic extension of this thesis is to study the relationship between ceos’ cognitive complexity (which is developed through specific training derived from the educational backgrounds) and corporate risk-taking. This can be further broken into two categories