MyMedR

Panikker VMB

Malayan Medical Journal, 1929;4:152.

Aerobic dynamic feeding as a strategy for in situ accumulation of polyhydroxyalkanoate in aerobic granules

Gobi K, Vadivelu VM

Bioresour Technol, 2014 Jun;161:441-5.

PMID: 24725384 DOI: 10.1016/j.biortech.2014.03.104

Aerobic dynamic feeding (ADF) strategy was applied in sequencing batch reactor (SBR) to accumulate polyhydroxyalkanoate (PHA) in aerobic granules. The aerobic granules were able to remove 90% of the COD from palm oil mill effluent (POME). The volatile fatty acids (VFAs) in the POME are the sole source of the PHA accumulation. In this work, 100% removal of propionic and butyric acids in the POME were observed. The highest amount of PHA produced in aerobic granules was 0.6833mgPHA/mgbiomass. The PHA formed was identified as a P (hydroxybutyrate-co-hydroxyvalerate) P (HB-co-HV).

Dynamics of polyhydroxyalkanoate accumulation in aerobic granules during the growth-disintegration cycle

Gobi K, Vadivelu VM

Bioresour Technol, 2015 Nov;196:731-5.

PMID: 26235884 DOI: 10.1016/j.biortech.2015.07.083

The polyhydroxyalkanoate (PHA) accumulation dynamics in aerobic granules that undergo the growth-disintegration cycle were investigated. Four sequencing batch reactors (SBR) were inoculated with aerobic granules at different stages of development (different sizes). Different sizes of aerobic granules showed varying PHA contents. Thus, further study was conducted to investigate the diffusion of substrate and oxygen on PHA accumulation using various organic loading rates (OLR) and aeration rates (AR). An increase in OLR from 0.91 to 3.64kg COD/m(3)day increased the PHA content from 0.66 to 0.87g PHA/g CDW. Meanwhile, an AR increase from 1 to 4L/min only accelerated the maximum PHA accumulation without affecting the PHA content. However, the PHA composition only changes with AR, while the hydroxyvalerate (HV) content increased at a higher AR.

Polyhydroxyalkanoate recovery and effect of in situ extracellular polymeric substances removal from aerobic granules

Gobi K, Vadivelu VM

Bioresour Technol, 2015;189:169-176.

PMID: 25889804 DOI: 10.1016/j.biortech.2015.04.023

Polyhydroxyalkanoate (PHA) recovery from aerobic granules was investigated using four cell digestion agents, namely, sodium hypochlorite, sodium hydroxide, acetone and sodium chloride. Simultaneously, the removal of extracellular polymeric substances (EPS) and its effect on PHA yield were investigated. The highest PHA recovery yield was obtained using sodium hypochlorite, accounting for 89% cell dry weight (CDW). The highest PHA was recovered after the sodium hypochlorite completely removed the EPS from the aerobic granules. The average molecular weight (Mw) of the PHA recovered using sodium hypochlorite was 5.31 × 10(5)g/mol with only 1.8% molecular weight degradation. The energy and duration analysis for PHA recovery revealed that the sodium hypochlorite method required the least amount of energy and time at 0.0561 MJ/g PHA and 26 h, respectively. The PHA that was recovered was a P3(HB-co-HV) co-polymer.

Effect of famine-phase reduced aeration on polyhydroxyalkanoate accumulation in aerobic granules

Vjayan T, Vadivelu VM

Bioresour Technol, 2017 Dec;245(Pt A):970-976.

PMID: 28946198 DOI: 10.1016/j.biortech.2017.09.038

The effects of variable aeration in the famine period on polyhydroxyalkanoate (PHA) accumulation in aerobic granules were investigated. Results showed that regardless of the aeration rates used during famine period, all aerobic granules achieved a similar chemical oxygen demand removal and PHA content. The decrease in famine-period aeration rates accelerated the maximum PHA accumulation together with increase in granular size and settling ability. The PHA-accumulating microorganisms were found to have shifted closer to the surface of the granules when the aeration rate was reduced. Moreover, PHA compositional changes occurred, where the hydroxyvalerate content had increased with the reduction in aeration rate. Ultimately, the results indicate that the requirement of aeration for PHA accumulation in aerobic granules is highly insignificant in the famine phase. PHA production in aerobic granules under zero aeration in the famine period may result in an energy input reduction of up to 74%.

Fulltext Pancreatoblastoma: a rare tumour accidentally found

Naik VR, Jaafar H, Leow VM, Bhavaraju VM

Singapore Med J, 2006 Mar;47(3):232-4.

PMID: 16518559

A 15-year-old girl, who was previously well, complained of a mass in the abdomen after a minor motor vehicle accident. Physical and radiological investigations revealed a mass in the body of pancreas containing proteinaceous material and multiple nodules in both lobes of liver. Serological investigations for malignancy were normal. Histopathological examination of the resected specimen showed pancreatoblastoma. Pancreatoblastoma is an unusual malignant tumour seen in infants and children although rare cases have also been reported in adults. They are clinicopathologically distinct from adult pancreatic ductal carcinoma. The histogenesis, clinical features and treatment options are discussed along with presentation of the case.

Treatment of agro based industrial wastewater in sequencing batch reactor: performance evaluation and growth kinetics of aerobic biomass

Lim JX, Vadivelu VM

J Environ Manage, 2014 Dec 15;146:217-225.

PMID: 25173730 DOI: 10.1016/j.jenvman.2014.07.023

A sequencing batch reactor (SBR) with a working volume of 8 L and an exchange ratio of 25% was used to enrich biomass for the treatment of the anaerobically treated low pH palm oil mill effluent (POME). The influent concentration was stepwise increased from 5000 ± 500 mg COD/L to 11,500 ± 500 mg COD/L. The performance of the reactor was monitored at different organic loading rates (OLRs). It was found that approximately 90% of the COD content of the POME wastewater was successfully removed regardless of the OLR applied to the SBR. Cycle studies of the SBR show that the oxygen uptake by the biomass while there is no COD reduction may be due to the oxidation of the storage product by the biomass. Further, the growth kinetic parameters of the biomass were determined in batch experiments using respirometer. The maximum specific growth rate (μmax) was estimated to be 1.143 day(-1) while the half saturation constant (Ks) with respect to COD was determined to be 0.429 g COD/L. The decay coefficient (bD) and biomass yield (Y) were found to be 0.131 day(-1) and 0.272 mg biomass/mg COD consumed, respectively.

Fulltext Effects of Lipid Solid Mass Fraction and Non-Lipid Solids on Crystallization Behaviors of Model Fats under High Pressure

Zulkurnain M, Balasubramaniam VM, Maleky F

Molecules, 2019 Aug 06;24(15).

PMID: 31390764 DOI: 10.3390/molecules24152853

Different fractions of fully hydrogenated soybean oil (FHSBO) in soybean oil (10-30% w/w) and the addition of 1% salt (sodium chloride) were used to investigate the effect of high-pressure treatments (HP) on the crystallization behaviors and physical properties of the binary mixtures. Sample microstructure, solid fat content (SFC), thermal and rheological properties were analyzed and compared against a control sample (crystallized under atmospheric condition). The crystallization temperature (Ts) of all model fats under isobaric conditions increased quadratically with pressure until reaching a pressure threshold. As a result of this change, the sample induction time of crystallization (tc) shifted from a range of 2.74-0.82 min to 0.72-0.43 min when sample crystallized above the pressure threshold under adiabatic conditions. At the high solid mass fraction, the addition of salt reduced the pressure threshold to induce crystallization during adiabatic compression. An increase in pressure significantly reduced mean cluster diameter in relation to the reduction of tc regardless of the solid mass fraction. In contrast, the sample macrostructural properties (SFC, storage modulus) were influenced more significantly by solid mass fractions rather than pressure levels. The creation of lipid gel was observed in the HP samples at 10% FHSBO. The changes in crystallization behaviors indicated that high-pressure treatments were more likely to influence crystallization mechanisms at low solid mass fraction.

Modifications to Hepatopancreatobiliary surgical services during COVID-19 partial lockdown in a hospital in northern Malaysia

Hassan R, Nijhar JS, Leow VM, Manisekar S

Med J Malaysia, 2021 09;76(5):714-717.

PMID: 34508379

Maintaining hepatopancreatobiliary (HPB) services during the initial phase of a pandemic in a state referral hospital for COVID-19 presents a few challenges, especially when a nationwide, government-issued partial lockdown is in enforcement. We describe the adaptations to our practice to maintain the services whilst ensuring safety of patients and staff, by postponing non-urgent clinic cases, grouping our staff to two mutually exclusive teams that work on alternate shifts and selecting HPB operative cases according to the modified Risk Urgency Decision Matrix.

Data on translatome analysis of Mycoplasma gallisepticum

Fisunov GY, Evsyutina DV, Govorun VM

Data Brief, 2016 Dec;9:422-424.

PMID: 27699194

Mycoplasma gallisepticum is a bacterium of class Mollicutes which encompasses wall-less bacteria with significantly reduced genomes. Due to their overall reduction and simplicity mycoplasmas serve as a model of minimal cell and are used for systems biology studies. Here we present raw data on translatome (ribosome-bound mRNA) analysis of Mycoplasma gallisepticum under logarithm growth and heat stress. The data supports the publication of "Ribosomal profiling of Mycoplasma gallisepticum" (G. Y. Fisunov, D. V Evsyutina, A. A. Arzamasov, I. O. Butenko, V. M. Govorun, 2015) [1].

Fulltext Primary hepatic angiosarcoma: difficulty in clinical, radiological, and pathological diagnosis

Yang KF, Leow VM, Hasnan MN, Subramaniam MK

Med J Malaysia, 2012 Feb;67(1):127-8.

PMID: 22582567 MyJurnal

Hepatic angiosarcoma is a rare primary mesenchymal malignancy. Prognosis is poor and mortality occurs early. The diagnosis is challenging. Our case was an asymptomatic 70 year-old man referred, with incidental ultrasonography finding of multiple liver nodules. Diagnostic laparoscopic liver biopsy and the histopathological examination reported a haemangioma. Six months later, he became symptomatic and his health condition deteriorated rapidly.

A parapharyngeal meningioma presenting as a neck mass and multiple cranial nerve palsies

Mohamad I, Abdullah B, Idris Z, Naik VR, Bhavaraju VM

Ceylon Med J, 2011 Jun;56(2):73-4.

PMID: 21789871

Fulltext Synchronous adenocarcinoma of caecum, transverse colon and jejunum

Leong BD, Ramu P, Kumar VM, Chuah JA

Med J Malaysia, 2008 Jun;63(2):148-9.

PMID: 18942304 MyJurnal

Synchronous cancers are defined as malignant tumours that occur simultaneously, each of which must be distinct with no possibility of one being the metastasis of the other. A 65 year old gentleman presented to us with two month history of epigastric pain associated with anaemia, loss of appetite and weight. He has no history of malignancy in his family. Colonoscopy revealed tumours at transverse colon and caecum. Intra-operatively, tumours were sited at caecum, transverse colon and jejunum. Tumours were diagnosed as synchronous adenocarcinoma histopathologically with loss of expression of MLH1 and MSH2. From literature search, this is the first reported triple synchronous tumours of the caecum, transverse colon and jejunum. We believe that this gentleman developed triple synchronous tumour through the sporadic MSI pathway.

Non-invasive cardiac assessment in beta-thalassaemia major

Ong ML, Hatle LK, Lai VM, Bosco J

Int J Clin Pract, 2002 Jun;56(5):345-8.

PMID: 12137442

Iron deposition in the heart occurs in beta-thalassaemia major and contributes to cardiac dysfunction. Eighteen patients with beta-thalassaemia major were assessed clinically and had non-invasive investigations. They were young (15.5 +/- 3.6 years). Two patients had clinical heart failure. Doppler echocardiography demonstrated higher transmitral peak flow velocity in early and late diastole compared with controls (e: p<0.05, a: p<0.01). Transtricuspid peak late diastolic flow velocity was higher in patients (p<0.005). Isovolumic relaxation time was shortened (p<0.001). Pulmonary venous flow velocity was higher in diastole than systole (S: 0.51 +/- 0.11 m/s, D: 0.62 +/- 0.08 m/s). Reversal of pulmonary venous flow during atrial systole was seen in eight patients. These diastolic filling abnormalities did not significantly change with blood transfusion. Left ventricular ejection fraction was normal in patients. Two patients had cardiomegaly on chest X-ray. In beta-thalassaemia with iron overload, there is a restrictive pattern of diastolic dysfunction. This is not altered by recent blood transfusion. Left ventricular function remains relatively intact.

The use of the resonant mirror biosensor to detect point mutations, as demonstrated with synthetic oligonucleotides

Momynaliev KT, Govorun VM, Gnedenko O, Ivanov YD, Archakov AI

J. Mol. Recognit., 2003 Jan-Feb;16(1):1-8.

PMID: 12557232

The possibility of using the resonant mirror biosensor to detect point substitutions in oligonucleotides was demonstrated with a fragment of the Helicobacter pylori 23S rRNA gene, point mutations in which are responsible for clarythromycin resistance. Conditions were optimized for the interaction of a probe immobilized on the sensing surface with targets containing various nucleotide substitutions. A probe allowing reliable discrimination of mutant targets was selected. The mismatch position in the probe was shown to affect the kinetic parameters (response) of hybridization with mutant targets, reporting not only the position, but also the character (G or C) of a substitution.

Fulltext Protein expression in sera of patients with amoebic liver abscess (ALA): potential use of haptoglobin as a surrogate disease marker

Othman N, Zainudin NS, Mohamed Z, Yahya MM, Leow VM, Noordin R

Trop Biomed, 2013 Jun;30(2):257-66.

PMID: 23959491 MyJurnal

The protein profile of serum samples from patients with amoebic liver abscess (ALA) was compared to those of normal individuals to determine their expression levels and to identify potential surrogate disease markers. Serum samples were resolved by two dimensional electrophoresis (2-DE) followed by image analysis. The up and down-regulated protein spots were excised from the gels and analysed by MS/MS. The concentration of three clusters of proteins i.e. haptoglobin (HP), α1-antitrypsin (AAT) and transferrin in serum samples of ALA patients and healthy controls were compared using competitive ELISA. In addition, serum concentrations of HP and transferrin in samples of patients with ALA and pyogenic liver abscess (PLA) were also compared. The results of the protein 2-DE expression analysis showed that HP cluster, AAT cluster, one spot each from unknown spots no. 1 and 2 were significantly up-regulated and transferrin cluster was significantly down-regulated in ALA patients' sera (p<0.05). The MS/MS analysis identified the unknown protein spot no.1 as human transcript and haptoglobin and spot no. 2 as albumin. Competitive ELISA which compared concentrations of selected proteins in sera of ALA and healthy controls verified the up-regulated expression (p<0.05) of HP and the down-regulated expression (p<0.01) of transferrin in the former, while there was no significant difference in AAT expression (p> 0.05). However, when ALA and PLA samples were compared, competitive ELISA showed significant increased concentration of HP (p<0.05) while transferrin levels were not different. In conclusion, this study showed that HP is a potential surrogate disease marker for ALA.

General nutrition knowledge among carers at group homes for people with intellectual disability

Hamzaid NH, Flood VM, Prvan T, O'Connor HT

J Intellect Disabil Res, 2018 05;62(5):422-430.

PMID: 29484759 DOI: 10.1111/jir.12480

BACKGROUND: Good nutrition knowledge among carers of people with intellectual disability (ID) living in group homes is essential as they have a primary role in food provision for residents. Research on the nutrition knowledge of carers is limited.

METHOD: This cross-sectional study assessed the level of general nutrition knowledge in a convenience sample of Australian carers (C) of people with ID and compared this to the general Australian community (CM). Nutrition knowledge was evaluated using the validated General Nutrition Knowledge Questionnaire. Total knowledge score as well as performance on instrument sub-sections (dietary guidelines, nutrient sources, healthy food choices and diet disease relationships) were assessed (expressed as %). Knowledge scores were adjusted for known confounders (age, sex, education level, BMI, living arrangement and English spoken at home) using generalised linear modelling.

RESULTS: A total of 589 participants were recruited (C: n = 40; CM: n = 549). Age (C: 40.8 ± 12.1 year; CM: 37.8 ± 13.3 years; P = 0.145), sex distribution (C: 62.5%; CM: 67.2% female; P = 0.602) and English spoken at home (C: 82.5%; CM: 89.6%; P = 0.183) were similar between groups, but BMI (C: 28.5 ± 5.7 kgm-2 ; CM: 25.3 kgm-2 ; P = 0.002) was significantly lower and tertiary education (C: 52.5%; CM: 85.1%; P

Fulltext Bizarre ECG in head injury mimicking ventricular tachycardia

Loke YK, Lai VM, Tan MH, Gunn A

Singapore Med J, 1997 Apr;38(4):166-8.

PMID: 9269397

Bizarre electrocardiographic (ECG) changes were found in an 18-year-old girl who had a subdural haematoma following head trauma. The initial diagnosis was of ventricular tachycardia (VT) and she was treated with intravenous anti-arrhythmic drugs and electrical cardioversion, but to no effect. It was later concluded that the ECG appearances were not of a ventricular arrhythmia but were the result of the intracranial pathology. ECG abnormalities related to head injuries have been reported on many occasions, and our case report illustrates how this can create difficulties for the attending clinicians.

Fulltext Two-incision three-port laparoscopic cholecystectomy. A feasible and safe technique

Leow VM, Faizah MS, Mohd Sharifudin S, Letchumanan VP, Yang KF, Manisekar KS

Med J Malaysia, 2014 Jun;69(3):129-32.

PMID: 25326354 MyJurnal

OBJECTIVE: Conventional laparoscopic cholecystectomy (LC) involves the use of four ports, but the number of ports has gradually been reduced to one for cosmetic reasons. however, single-incision LC is technically demanding, and there is a substantial learning curve associated with its successful application. The aim of this clinical study was to evaluate the safety and feasibility of a less demanding alternative LC technique with a faster learning curve.

METHODS: This prospective descriptive study was performed from September 2009 to February 2011 at Sultanah Bahiyah hospital in Kedah, Malaysia. A total of 58 patients underwent two-incision threeport laparoscopic cholecystectomy (TILC), which was performed by the senior consultant hepato-pancreato-biliary surgeon and two hepato-pancreato-biliary trainees. Study end points included operative time, postoperative pain, length of hospital stay and early postoperative complications. The follow-up period was 4 weeks.

RESULTS: The overall operative time taken was 44 ± 18 minutes. none of the patients had major complication or incisional hernia postoperatively. All but one of the patients were discharged within 24 h. nonsteroidal anti-inflammatory drugs were the main postoperative analgesic used.

CONCLUSION: TILC is feasible and safe cholecystectomy technique.

Fulltext Tuberculosis of gallbladder with candidiasis, a rare entity

Leong BD, Chan KW, Ramu P, Kumar VM, Chuah JA

Med J Malaysia, 2011 Jun;66(2):146-7.

PMID: 22106698 MyJurnal

Gallbladder tuberculosis (GT) is an extremely rare condition. This is thought to be due to the protective property of bile against the infection. Clinical and radiological diagnosis of GT is difficult. We describe a case of GT who initially presented to us with jaundice, a right hypochondrial mass and computed tomographic findings suggestive of gallbladder empyema. Diagnosis was made from histopathological examination of the resected gallbladder which revealed epitheloid granulomas with caseating necrosis and presence of Langhan's giant cells. From a literature search and to the best of our knowledge, this is the first GT to be reported in South East Asia.

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