1.Synthesis and characterization of poly(p-phenylene vinylene).
Abd Rashid MY ; Abu Bakar A ; Mohd Asri MT ; Iskandar SM
The Medical Journal of Malaysia 2004;59 Suppl B():135-136
Poly (p-phenylene vinylene) (PPV) was synthesized from p-xylylene bis(tetrahydrothiophenium chloride) using the Wessling route and characterized by Fourier Transform Infra-Red (FTIR) and UV-visible (UV-VIS) spectroscopic techniques. The significance of thermal treatment along with evolution of precursor polymer to polymer PPV was also studied through these spectroscopic techniques. Thermally Stimulated Current (TSC) measurements indicated the presence of crystallization, sulphonium group which occurred through the evolution from precursor polymer to polymer PPV during thermal treatment.
Polymers/analysis
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Polymers/*chemical synthesis
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Polyvinyls/analysis
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Polyvinyls/*chemical synthesis
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Spectroscopy, Fourier Transform Infrared
2.Effects of carbon source and additives on biomass, exopolysaccharide production and morphology of Pleurotus ostreatus in submerged cultivation
Nor Zalina Othman ; Abd. Rahman Jabir Mohd. Din ; Khairun Hani Natasya Zakaria ; Solleh Ramli ; Leong Hong Yeng ; Siti Norazlina Abd. Rashid ; Mohd. Mokhtar Mohd. Yunus ; Mohamad Roji Sarmidi
Malaysian Journal of Microbiology 2019;15(5):358-365
Aims:
To investigate the influence of carbon sources and additives/surfactants on the mycelium growth and exopolysaccharides (EPS) production, including the morphology during submerged cultivation of Pleurotus ostreatus in the minimal-medium as the base medium.
Methodology and results:
Pleurotus ostreatus was cultivated in different types of carbon sources to investigate the effects of carbon sources to mycelium growth and changes of mycelium morphology which directly affects the synthesis of EPS. In addition, additives or surfactants can increase the bioavailability of less soluble substrates in the cultured medium for the mycelium growth and indirectly affects the EPS production. In this study, the cultivation of P. ostreatus in the minimal-medium by using glucose as the carbon source with the addition of lecithin at 1% (w/v) gave the highest EPS production 4.53 ± 0.30 g/L, an increase of about 89.53% when compared to the cultivation without the addition of lecithin. Addition of lecithin changes morphology of the pellets outer layer and under microscope showing a dense hyphal network surrounding the pellets with the sizes of micro pellets almost 0.5-1.5 mm which contributed to the increase of EPS production after 14 days cultivation at 26 °C
Conclusion, significance and impact of study
The choice of the carbon source should not only be for high productivity rate of mycelium growth and EPS production, but a cheaper alternative source should also be considered. In conclusion, high mycelium biomass and EPS production was achieved either by changes of the morphology through the type of carbon source and addition of additives such as lecithin.
3.Angular Deformities of the Knee in Children Treated with Guided Growth
Jamil K ; Yahaya MY ; Abd-Rasid AF ; Ibrahim S ; Abdul-Rashid AH
Malaysian Orthopaedic Journal 2021;15(No.2):26-35
Introduction: The guided growth technique is an alternative
to corrective osteotomy for treating angular deformities of
the extremities. It has the advantage of being minimally
invasive and is effective in a growing child. This study
reports on the outcome of guided growth technique using a
plate in correcting knee angular deformities.
Materials and methods: We conducted a retrospective study
of children with angular deformity of the knee treated by the
guided growth technique from January 2010 to December
2015 in a tertiary centre. The guided growth technique was
done using either the flexible titanium plate (8-plate) or the 2-
hole reconstruction plate. Correction of deformity was
assessed on radiographs by evaluating the mechanical axis
deviation and tibiofemoral angle. The implants were removed
once deformity correction was achieved.
Results: A total of 17 patients (27 knees) were evaluated.
Twenty-two knees (81.5%) achieved complete correction of
the deformity. The median age was 4.0 (interquartile range
3.0-6.0) years and the median Body Mass Index (BMI) was
26.0 (25.0-28.0). There were 7 unilateral and 10 bilateral
deformities with different pathologies (14 tibia vara, 3 genu
valgus). The median rate of correction was 0.71° per month.
One patient (1 knee) had screw pull-out and two patients (4
knees) had broken screws in the proximal tibia. Three
patients (5 knees) failed to achieve complete correction and
were subsequently treated with corrective osteotomies. Out
of five patients (8 knees) who were followed-up for at least
12 months after removal of hardware, two had rebound
deformities. No permanent growth retardation occurred in
our patients.
Conclusion: Our outcome for guided growth to correct knee
angular deformity was similar to other studies. Guided
growth is safe to perform in children below 12 years old and
has good outcome in idiopathic genu valgus and Langeskiold
II for tibia vara. Patients should be observed for recurrence
until skeletal maturity following implant removal.