MyMedR

Fulltext A Review on Haematococcus pluvialis Bioprocess Optimization of Green and Red Stage Culture Conditions for the Production of Natural Astaxanthin

Oslan SNH, Shoparwe NF, Yusoff AH, Rahim AA, Chang CS, Tan JS, et al.

Biomolecules, 2021 02 10;11(2).

PMID: 33578851 DOI: 10.3390/biom11020256

As the most recognizable natural secondary carotenoid astaxanthin producer, the green microalga Haematococcus pluvialis cultivation is performed via a two-stage process. The first is dedicated to biomass accumulation under growth-favoring conditions (green stage), and the second stage is for astaxanthin evolution under various stress conditions (red stage). This mini-review discusses the further improvement made on astaxanthin production by providing an overview of recent works on H. pluvialis, including the valuable ideas for bioprocess optimization on cell growth, and the current stress-exerting strategies for astaxanthin pigment production. The effects of nutrient constituents, especially nitrogen and carbon sources, and illumination intensity are emphasized during the green stage. On the other hand, the significance of the nitrogen depletion strategy and other exogenous factors comprising salinity, illumination, and temperature are considered for the astaxanthin inducement during the red stage. In short, any factor that interferes with the cellular processes that limit the growth or photosynthesis in the green stage could trigger the encystment process and astaxanthin formation during the red stage. This review provides an insight regarding the parameters involved in bioprocess optimization for high-value astaxanthin biosynthesis from H. pluvialis.

Fulltext A comparative study on the accuracy of noninvasive thermometers

Fadzil FM, Choon D, Arumugam K

Aust Fam Physician, 2010 Apr;39(4):237-9.

PMID: 20372685

This study assessed the concordance of the temperatures of the digital, liquid crystal forehead and digital infrared tympanic thermometers with the mercury in glass thermometer.

ALEXIS O-Ring wound retractor vs conventional wound protection for the prevention of surgical site infections in colorectal resections(1)

Cheng KP, Roslani AC, Sehha N, Kueh JH, Law CW, Chong HY, et al.

Colorectal Dis, 2012 Jun;14(6):e346-51.

PMID: 22568647 DOI: 10.1111/j.1463-1318.2012.02943.x

Surgical site infection (SSI) remains a common postoperative morbidity, particularly in colorectal resections, and poses a significant financial burden to the healthcare system. The omission of mechanical bowel preparation, as is performed in enhanced recovery after surgery programmes, appears to further increase the incidence. Various wound protection methods have been devised to reduce the incidence of SSIs. However, there are few randomized controlled trials assessing their efficacy. The aim of this study is to investigate whether ALEXIS wound retractors with reinforced O-rings are superior to conventional wound protection methods in preventing SSIs in colorectal resections.

Awareness, perception and barriers to seeking information from online academic databases and medical journals as sources of information

Wong LP, Mohamad Shakir SM, Tong WT, Alias H, Aghamohammadi N, Arumugam K

Inform Health Soc Care, 2018 Dec;43(4):335-347.

PMID: 29035606 DOI: 10.1080/17538157.2017.1364248

Medical students' use of online medical journals as a source of information is crucial in the learning pathway to become medical doctors. We conducted a cross-sectional survey study among University medical students between December 2012 and March 2013 to assess their awareness, perceived usefulness, practices, and barriers to seeking information from online academic databases and medical journals. The response rate was 67.53%. The majority of the students knew of the availability of online academic databases and medical journals. The mean score for awareness (4.25 of possible 11.0), perceived usefulness (13.95 of possible 33.0), and practice (10.67 of possible 33.0) were low. The mean barrier score toward using online academic databases and medical journals was 25.41 (of possible 45.0). Multivariate findings showed that significant barriers associated with overall usage of online databases and medical journals were 1) not knowing where or how to locate databases and 2) unsureness of using the Boolean operators. Availability of full text subscriptions was found to be an important factor in using online databases. Study findings highlighted the need to increase awareness of academic databases' availability and increase training on ways to search online academic databases and medical journals.

Caesarean section and asthma in Malaysian children: a case-control study

Nathan AM, de Bruyne J, Khalid F, Arumugam K

Asian Pac J Allergy Immunol, 2012 Sep;30(3):204-8.

PMID: 23156850

Birth cohort studies in some countries have shown a link between caesarean section and asthma.

Causes for infertility: a comparative study

Arumugam K, Urquhart R

Ann Acad Med Singap, 1991 May;20(3):351-2.

PMID: 1929177

A representative group of 204 infertile couples from Kuala Lumpur, Malaysia were compared to a similar group of 633 couples from Aberdeen, UK in an attempt to study if there was any regional difference in the pattern of infertility seen. The protocol for investigation and diagnostic criteria for both centres were standardised. A significant difference (X2 = 63.43; p less than 0.001) was seen. The reasons for these differences are discussed.

Fulltext Combined pregnancy--a case report

Kumarasamy S, Arumugam K

Med J Malaysia, 1991 Sep;46(3):252-4.

PMID: 1839921

A case of combined intra- and extra-uterine pregnancy is reported. Awareness of this condition, a high index of suspicion, the proper interpretation of physical signs and ultrasound findings together with early resort to laparoscopy resulted in a favourable outcome.

De novo formation of adhesions in endometriosis: the role of iron and free radical reactions

Arumugam K, Yip YC

Fertil Steril, 1995 Jul;64(1):62-4.

PMID: 7789581

OBJECTIVE: To show that raised iron levels in the peritoneal fluid (PF) of patients with endometriosis catalyze free radical reactions that results in the tissue destruction and fibrosis seen in these patients.

DESIGN: A case-controlled study of the iron levels (microgram/mL) in the pelvic PF of 12 patients with moderate-to-severe disease, 15 patients with minimal-to-mild disease and in 17 women with normal pelvises were compared. As an index of free radical reactions through lipid peroxidation, the levels of malondialdehyde levels (ng/mL) were assessed simultaneously in the same specimens.

RESULTS: Controlling for the phase of the menstrual cycle, significantly higher levels of iron were seen in patients with endometriosis, the levels being correlated with the severity of the disease. However no such corresponding relationship was seen in the malondialdehyde levels in the PF.

CONCLUSIONS: These results suggest that raised iron levels in the PF do not play a role in catalyzing free radical reactions as judged by the degree of lipid peroxidation.

Emergency cervical circlage for cervical incompetence

Arumugam K, Ratnavale M

J Obstet Gynaecol, 1997 Jan;17(1):49-50.

PMID: 15511765

Twelve patients had emergency cervical circlage for inevitable middle trimester abortion due to cervical incompetence. The mean gestation was 23 weeks (range 15-28 weeks). The median cervical dilatation was 3 cm. In three patients, the cervical dilatation was more than 5 cm. The median prolongation of pregnancy was 3.3 weeks (range 4 days to 10 weeks). Eight of the 14 babies survived. All babies that survived were more than 1000 g. Based on our experience, we advocate an active approach to inevitable middle trimester abortions due to cervical incompetence.

Endometriosis and infertility: raised iron concentration in the peritoneal fluid and its effect on the acrosome reaction

Arumugam K

Hum Reprod, 1994 Jun;9(6):1153-7.

PMID: 7962392

Endometriosis and infertility are commonly associated. This study investigated the role of accelerated lipid peroxidation of spermatozoa by the peritoneal fluid of patients with endometriosis as a cause for this association. It proposes that the increased iron concentration present in the fluid of these patients acts as a catalyst for the process. Peritoneal fluid from 25 patients with endometriosis and 25 matched controls was obtained at laparoscopy. Spermatozoa were incubated in the fluid from both groups and the subsequent acrosome reaction rates analysed. The relationship between these results and iron concentration in the fluid was examined. A significant decrease in the acrosome reaction rate was seen in the endometriotic group (P = 0.034). Overall, a decrease in the acrosome reaction rate was associated with an increased iron concentration in the fluid (18 of the 25 pairs). In mild disease, (six of 11 pairs), the relationship was not as marked as that in severe disease (12 of 14 pairs). These results suggest that the peritoneal fluid in patients with endometriosis has a detrimental action on the acrosome reaction of spermatozoa in vitro.

Endometriosis and infertility: the role of exogenous lipid peroxides in the peritoneal fluid

Arumugam K, Dip YC

Fertil Steril, 1995 Jan;63(1):198-9.

PMID: 7805914

OBJECTIVE: To determine if lipid peroxides were raised in the pelvic peritoneal fluid of patients with endometriosis.

DESIGN: Control study involving patients with and without endometriosis.

METHODS: The lipid peroxide (malondialdehyde) levels in the pelvic PF of 12 patients with moderate-to severe endometriosis, 15 patients with minimal-mild endometriosis and 13 patients with normal pelvises were compared.

RESULTS: The level of lipid peroxides were not affected by the presence nor the severity of endometriosis.

CONCLUSION: Accelerated lipid peroxidation does not appear to play a role in the causal relationship between endometriosis and infertility.

Endometriosis and race

Arumugam K, Templeton AA

Aust N Z J Obstet Gynaecol, 1992 May;32(2):164-5.

PMID: 1520204

The pelvic findings of 202 infertile women undergoing diagnostic laparoscopy in Kuala Lumpur, Malaysia were compared to that of 464 infertile women undergoing diagnostic laparoscopy in Aberdeen, United Kingdom. Endometriosis was significantly more common in the women from Kuala Lumpur (51% against 22%, p less than 0.001). There was however no significant difference seen in the severity of the disease (AFS Classification, 1985). These findings confirm our clinical impression that endometriosis is more common in Asian women when compared to Caucasian women.

Endometriosis and social class

Arumugam K, Templeton AA

Med J Aust, 1990 Nov 05;153(9):567.

PMID: 2233493

Endometriosis and social class: an Asian experience

Arumugam K, Welluppilai S

Asia Oceania J Obstet Gynaecol, 1993 Sep;19(3):231-4.

PMID: 8250754

The social class distribution in 147 patients confirmed to have endometriosis at laparoscopy was done to see if the disease was associated with affluence. Two hundred and eighty-one patients confirmed not to have endometriosis was used as controls. The patients were derived from a background population for which the social class characteristics was known. Endometriosis was significantly (p < 0.001) associated with social class 1 and 2. However there was no association between social class distribution and the severity of the disease developed.

Fulltext Enhancement of Biomass and Calcium Carbonate Biomineralization of Chlorellavulgaris through Plackett-Burman Screening and Box-Behnken Optimization Approach

Chin ZW, Arumugam K, Ashari SE, Faizal Wong FW, Tan JS, Ariff AB, et al.

Molecules, 2020 Jul 28;25(15).

PMID: 32731437 DOI: 10.3390/molecules25153416

The biosynthesis of calcium carbonate (CaCO3) minerals through a metabolic process known as microbially induced calcium carbonate precipitation (MICP) between diverse microorganisms, and organic/inorganic compounds within their immediate microenvironment, gives rise to a cementitious biomaterial that may emerge as a promissory alternative to conventional cement. Among photosynthetic microalgae, Chlorella vulgaris has been identified as one of the species capable of undergoing such activity in nature. In this study, response surface technique was employed to ascertain the optimum condition for the enhancement of biomass and CaCO3 precipitation of C. vulgaris when cultured in Blue-Green (BG)-11 aquaculture medium. Preliminary screening via Plackett-Burman Design showed that sodium nitrate (NaNO3), sodium acetate, and urea have a significant effect on both target responses (p < 0.05). Further refinement was conducted using Box-Behnken Design based on these three factors. The highest production of 1.517 g/L C. vulgaris biomass and 1.143 g/L of CaCO3 precipitates was achieved with a final recipe comprising of 8.74 mM of NaNO3, 61.40 mM of sodium acetate and 0.143 g/L of urea, respectively. Moreover, polymorphism analyses on the collected minerals through morphological examination via scanning electron microscopy and crystallographic elucidation by X-ray diffraction indicated to predominantly calcite crystalline structure.

Fulltext Enhancement of targeted microalgae species growth using aquaculture sludge extracts

Arumugam K, Ahmad MF, Yaacob NS, Ikram WM, Maniyam MN, Abdullah H, et al.

Heliyon, 2020 Jul;6(7):e04556.

PMID: 32775725 DOI: 10.1016/j.heliyon.2020.e04556

Natural growth-promoting nutrients extracted from aquaculture sludge waste can be used to maximise microalgal growth. This study identified the influence of aquaculture sludge extract (SE) on four microalgae species. Conway or Bold's Basal Media (BBM) was supplemented with SE collected from a Sabak Bernam shrimp pond (SB) and Kota Puteri fish pond (KP), and tested using a novel microplate-incubation technique. Five different autoclave extraction treatment parameters were assessed for both collected SE, i.e., 1-h at 105 °C, 2-h at 105 °C, 1-h at 121 °C, 2-h at 121 °C, and 24-h at room temperature (natural extraction). Microalgae culture in the microplates containing control (media) and enriched (media + SE) samples were incubated for nine days, at 25 °C with the light intensity of 33.75 μmol photons m-2 s-1 at 12-h light/dark cycle. The total dissolved nitrogen (TDN) and total dissolved phosphorus (TDP) in KP SE were 44.0-82.0 mg L-1 and 0.96-8.60 mg L-1. TDN (8.0%-515.0%) and TDP (105%-186 %) were relatively higher in KP SE compared to SB SE. The growth of microalgae species Nannochloropsis ocenica showed significant differences (p < 0.05) between the five extraction treatments from SB and the control. However, Chlorella vulgaris, Neochloris conjuncta, and Nephroclamys subsolitaria showed no significant differences (p > 0.05) in SB SE. N. ocenica, C. vulgaris, and N. conjuncta showed significant differences (p < 0.05) between five extraction treatments from KP and the control while N. subsolitaria showed no significant difference (p > 0.05). The specific growth rate (SGR) in the exponential phase of all microalgae species were relatively higher in SB SE compared to KP SE. While the organic matter content of KP SE was relatively higher, there were no significant differences in microalgae growth compared to SB SE. Nonetheless, modified SE did influence microalgae growth compared to the control. This study shows that modified SE could be used as enrichment media for microalgae cultivation.

Fulltext Glycated haemoglobin is a good predictor of neonatal hypoglycaemia in pregnancies complicated by diabetes

Arumugam K, Abdul Majeed N

Malays J Pathol, 2011 Jun;33(1):21-4.

PMID: 21874747 MyJurnal

We investigated the usefulness of a single value of maternal HbA1c in late pregnancy as a predictor for neonatal hypoglycaemia and secondly, to find the appropriate threshold value. A prospective analysis of the HbA1c concentration between 36 to 38 weeks of gestation in 150 pregnant mothers with either pre-existing or gestational diabetes was performed. At delivery, glucose levels in the cord blood were analysed. Neonatal hypoglycaemia was defined as a blood sugar level of < 2.6 mmol/l. Receiver operator characteristic curve was constructed to evaluate the value of HbA1c concentration in predicting hypoglycaemia. There were 16 foetuses who were hypoglycaemic at delivery. The area under the ROC curve for predicting neonatal hypoglycaemia was 0.997 with a 95% confidence interval of 0.992 to 1, a very good prediction rate. The optimal threshold value for HbA1c in predicting hypoglycaemia in the foetus was 6.8% (51 mmol/mol). HbA1c level in late pregnancy is a good predictor for hypoglycaemia in the newborn.

Hysterosalpingography -- a Malaysian experience

Arumugam K, Ng KB

Malays J Reprod Health, 1987 Dec;5(2):85-8.

PMID: 12315186

Fulltext Impact of socio-economic class on colorectal cancer patient outcomes in Kuala Lumpur and Kuching, Malaysia

Kong CK, Roslani AC, Law CW, Law SC, Arumugam K

Asian Pac J Cancer Prev, 2010;11(4):969-74.

PMID: 21133609

OBJECTIVE: Research over the past several decades has indicated that low socioeconomic class has a direct effect on health outcomes. In Malaysia, class distribution may differ with the region. The objective of this study was to compare the presentation and survival of colorectal cancer patients in two dissimilar cities, Kuala Lumpur and Kuching, Sarawak.

METHODS: All patients diagnosed with a malignancy of the colon or rectum in Sarawak General Hospital and University of Malaya Medical Center from 1st Jan 2000-31st Dec 2006 were recruited. Data on presentation, socio-economic class and survival were obtained. The survival duration was categorized into more than three years or three years and less. Testing for significance was performed using the chi-square test, with p values less than 0.05 considered statistically significant.

RESULTS: A total of 565 patients in UMMC and 642 patients in SGH had a new diagnosis of colorectal carcinoma. Patients in Kuching had a longer duration of symptoms and more advanced stage at presentation, but this was not statistically significant. Lower socio-economic class was a significant factor for late and more advanced stage at diagnosis, as well as poorer three and five year survival rates. However, survival was lower for patients in Kuching compared to Kuala Lumpur, even after matching for socio-economic class.

CONCLUSION: There is near-zero awareness of colorectal cancer screening in Malaysia. These findings support reaching out to communities of lower socioeconomic backgrounds to improve the colorectal cancer survival rates.

Increased fracture risk and osteoporosis not associated with vitamin D levels in Malaysian patients with inflammatory bowel disease

Hilmi I, Sunderesvaran K, Ananda V, Sarji SA, Arumugam K, Goh KL

J Clin Endocrinol Metab, 2013 Jun;98(6):2415-21.

PMID: 23553858 DOI: 10.1210/jc.2013-1147

INTRODUCTION: Osteoporosis and osteopenia are well-recognized complications of inflammatory bowel disease. Previous studies have suggested that vitamin D deficiency is an important risk factor for the development of osteoporosis. We hypothesized that low vitamin D levels is the main reason for reduced bone mineral density in patients with inflammatory bowel disease. We aimed to study its potential role in Malaysia, which is a tropical country with 3 large ethnic groups. We also sought to examine the relationship between fracture risk and bone mineral density in this group.
METHODOLOGY: Relevant history as well as 25-hydroxycholecalciferol (vitamin D) levels and bone mineral density were obtained. Normal, inadequate, and low vitamin D levels were defined as 61-160 nmol/L (24-64 ng/mL), 30-60 nmol/L (12-24 ng/mL), and less than 30 nmol/L (<12 ng/mL), respectively.
RESULTS: Seventy-two patients were recruited. The prevalence of osteopenia and osteoporosis, respectively, were 58% and 17% in the spine and 51% and 14% in the hip. Mean vitamin D level in the group was low at 45.12 ± 17.4 nmol/L (18.05 ± 6.96 ng/mL), but there was no significant association between bone mineral density and vitamin D level. Twelve patients (16.7%) had a fragility fracture after the diagnosis of inflammatory bowel disease. The cumulative fracture incidence was 10% at 5 years and 35% at 10 years. There was a statistically significant association between osteoporosis of hip and a history of fracture (odds ratio 5.889; 95% confidence interval 1.41-24.53, P = .009).
CONCLUSION: Osteoporosis is prevalent among Malaysian patients with inflammatory bowel disease and is associated with a 6-fold increased risk of fractures. Most inflammatory bowel disease patients had inadequate or low vitamin D levels, but there was no association between vitamin D levels and BMD.

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