MyMedR

Anaerobic degradation of palm oil mill effluent (POME)

Yoochatchaval W, Kumakura S, Tanikawa D, Yamaguchi T, Yunus MF, Chen SS, et al.

Water Sci Technol, 2011;64(10):2001-8.

PMID: 22105121 DOI: 10.2166/wst.2011.782

The biodegradation characteristics of palm oil mill effluent (POME) and the related microbial community were studied in both actual sequential anaerobic ponds in Malaysia and enrichment cultures. The significant degradation of the POME was observed in the second pond, in which the temperature was 35-37 °C. In this pond, biodegradation of major long chain fatty acids (LCFA), such as palmitic acid (C16:0) and oleic acid (C18:1), was also confirmed. The enrichment culture experiment was conducted with different feeding substrates, i.e. POME, C16:0 and C18:1, at 35 °C. Good recovery of methane indicated biodegradation of feeds in the POME and C16:0 enrichments. The methane production rate of the C18:1 enrichment was slower than other substrates and inhibition of methanogenesis was frequently observed. Denaturing gradient gel electrophoresis (DGGE) analyses indicated the existence of LCFA-degrading bacteria, such as the genus Syntrophus and Syntorophomonas, in all enrichment cultures operated at 35 °C. Anaerobic degradation of the POME under mesophilic conditions was stably processed as compared with thermophilic conditions.

Expression and characterization of anticoagulant activity of salivary protein alALP from Asian tiger mosquito Aedes albopictus

Li XP, Lin D, Zhang Y, Chen SQ, Bai HQ, Zhang SN, et al.

Trop Biomed, 2020 Mar 01;37(1):116-126.

PMID: 33612723

Several bioactive molecules isolated from the saliva of blood-sucking arthropods, such as mosquitoes, have been shown to exhibit potential anticoagulant function. We have previously identified a 30kDa allergen named Aegyptin-like protein (alALP), which is highly homologous to Aegyptin, from the salivary glands of female Aedes albopictus (Asian tiger mosquito). In this study, we identified the conserved functional domain of alALP by using bioinformatic tools, and expressed the His-tagged alALP recombinant protein in sf9 insect cells by generation and transfection of a baculoviral expression plasmid carrying the fulllength cDNA of alALP. We purified this recombinant protein and examined its function on the inhibition of blood coagulation. The results showed that the purified His-alALP prolonged the Activated Partial Thromboplastin Time (APTT), Prothrombin Time (PT) and Thrombin Time (TT) in vitro as well as the Bleeding Time (BT) in vivo, which suggest that alALP could be a novel anticoagulant.

Parasitological and molecular detection of human fascioliasis in a young man from Guizhou, China

Chen MX, Zhang RL, Xu XN, Yu Q, Huang DN, Liu W, et al.

Trop Biomed, 2020 Mar 01;37(1):50-57.

PMID: 33612717

A 24-year-old man born in Guizhou province was diagnosed with obstructive jaundice and bile duct stones in 2013. Four living trematodes were found during laparotomy and cholecystectomy. Based on the morphology and molecular genetics analysis of internal transcribed spacer and pcox1 genes of the flatworm specimens, the trematodes from the patient were confirmed to be Fasciola hepatica. This report provided the clinical and molecular diagnosis information on human fascioliasis, which is an emerging sanitary problem still ignored in China. Human fascioliasis constantly occurs due to climatic changes and frequency of human travel. Therefore, it deserves more attention from physicians working in both developing and developed countries.

microRNAs expression profiles in Schistosoma japonicum of different sex 14 and 28 days post-infection

Ai L, Hu W, Zhang RL, Huang DN, Chen SH, Xu B, et al.

Trop Biomed, 2020 Dec 01;37(4):947-962.

PMID: 33612748 DOI: 10.47665/tb.37.4.947

Different miRNAs are involved in the life cycles of Schistosoma japonicum. The aim of this study was to examine the expression profile of miRNAs in individual S. japonicum of different sex before and after pairing (18 and 24 dpi). The majority of differential expressed miRNAs were highly abundant at 14 dpi, except for sja-miR-125b and sja-miR-3505, in both male and female. Moreover, it was estimated that sja-miR-125b and sja-miR-3505 might be related to laying eggs. sja-miR-2a-5p and sja-miR-3484-5p were expressed at 14 dpi in males and were significantly clustered in DNA topoisomerase III, Rap guanine nucleotide exchange factor 1 and L-serine/L-threonine ammonia-lyase. Target genes of sja-miR-2d-5p, sja-miR-31- 5p and sja-miR-125a, which were expressed at 14 dpi in males but particularly females, were clustered in kelch-like protein 12, fructose-bisphosphate aldolase, class I, and heat shock protein 90 kDa beta. Predicted target genes of sja-miR-3483-3p (expressed at 28 dpi in females but not in males) were clustered in 26S proteasome regulatory subunit N1, ATPdependent RNA helicase DDX17. Predicted target genes of sja-miR-219-5p, which were differentially expressed at 28 dpi in females but particularly males, were clustered in DNA excision repair protein ERCC-6, protein phosphatase 1D, and ATPase family AAA domaincontaining protein 3A/B. Moreover, at 28 dpi, eight miRNAs were significantly up-regulated in females compared to males. The predicted target genes of these miRNAs were significantly clustered in heat shock protein 90 kDa beta, 26S proteasome regulatory subunit N1, and protein arginine N-methyltransferase 1. To sum up, differentially expressed miRNAs may have an essential role and provide necessary information on clarifying this trematode's growth, development, maturation, and infection ability to mammalian hosts in its complex life cycle, and may be helpful for developing new drug targets and vaccine candidates for schistosomiasis.

Pneumonia and diarrhoeas: killers of toddlers in developing countries

Chen ST

Trop Geogr Med, 1975 Mar;27(1):103-8.

PMID: 806152

Pneumonia and diarrhoeas are an important cause of toddler mortality and morbidity in developing countries. Of the 147 children admitted to the University Hospital at Kuala Lumpur in 1971 for pneumonia and diarrhoeas 50 (34%) were found to be suffering from protein-calorie malnutrition of varying degrees of severity. The malnourished children tended to come from poorer homes, and to have a larger number of siblings born in rapid succession when compared with normal weight children. Anemia was more common among the malnourished children. The interaction of infection and malnutrition and the social implications of these diseases are important. It is vital that hospitals in developing countries promote health in addition to their traditional curative role.

Some epidemiological aspects of diphtheria in Malaysia

Chen ST, Puthucheary SD

Trop Geogr Med, 1976 Sep;28(3):211-5.

PMID: 1006789

In Malysia, the proportion of children fully immunized againest diphtheria is generally low (20%). On the other hand, the Schick conversion rate rises with age and reaches 90% by 11 years of age. It is noted that asymptomatic carriers are an important epidemiological factor in diphtheria and that carrier rates for school children are high (prevalence of 7.5% while the rate of coloization with C. diphtheriae over a period of one year was 30%). Although immunization protects against clinical diphtheria, it does not prevent the carrier state. Thus, for the control of diphtheria, one should aim for 100% compliance. Some suggestions as to how higher levels of immunity may be achieved are described.

Morbidity pattern amongst some primary school entrants in Malaysia

Chen ST, Dugdale AE

Trop Geogr Med, 1972 Sep;24(3):269-74.

PMID: 4636102

Beta haemolytic streptococcal carriers among normal schoolchildren

Chen ST, Dugdale AE, Puthucheary SD

Trop Geogr Med, 1972 Sep;24(3):257-64.

PMID: 4636100

Fulltext Study protocol for an open labelled randomised controlled trial of perioperative oral nutrition supplement in breast and colorectal cancer patients undergoing elective surgery

Wong TX, Chen ST, Ong SH, Shyam S, Kandasami P, Chee WSS

Trials, 2021 Nov 03;22(1):767.

PMID: 34732233 DOI: 10.1186/s13063-021-05716-5

BACKGROUND: While it is well established that perioperative use of oral nutrition supplement (ONS) improves nutrition status among severely malnourished surgical cancer patients, the evidence requires further substantiation for non-severely malnourished patients with cancer. This protocol paper presents the rationale and design of a randomised controlled trial to evaluate the effectiveness of preoperative as well as an extended 90-day postoperative use of ONS on nutritional and clinical outcomes among patients undergoing elective surgery for breast and colorectal cancer.

METHODS: Patients with primary breast and colorectal cancer undergoing elective surgery are recruited from two tertiary hospitals. Eligible patients are assigned into one of the three intervention arms: (i) Group SS will receive ONS in addition to their normal diet up to 14 days preoperatively and postoperatively up to discharge; (ii) Group SS-E will receive ONS in addition to their normal diet up to 14 days preoperatively, postoperatively up to discharge and for an extended 90 days after discharge; and (iii) Group DS will receive ONS in addition to their normal diet postoperatively up to discharge from the hospital. The ONS is a standard formula fortified with lactium to aid in sleep for recovery. The primary endpoints include changes in weight, body mass index (BMI), serum albumin and prealbumin levels, while secondary endpoints are body composition (muscle and fat mass), muscle strength (handgrip strength), energy and protein intake, sleep quality, haemoglobin, inflammatory markers (transferrin, high sensitivity C-reactive protein, interleukin-6), stress marker (saliva cortisol), length of hospital stay and postoperative complication rate.

DISCUSSION: This trial is expected to provide evidence on whether perioperative supplementation in breast and colorectal cancer patients presenting with high BMI and not severely malnourished but undergoing the stress of surgery would be beneficial in terms of nutritional and clinical outcomes.

TRIAL REGISTRATION: ClinicalTrial.gov NCT04400552. Registered on 22 May 2020, retrospectively registered.

Protein calorie malnutrition: a major health problem of multiple causation in Malaysia

Chen ST

Southeast Asian J. Trop. Med. Public Health, 1974 Mar;5(1):85-9.

PMID: 4209141

Comparative growth of Malay, Chinese and Indian school children in Malaysia

Chen ST

Southeast Asian J. Trop. Med. Public Health, 1976 Sep;7(3):443-51.

PMID: 1030848

The weights and heights of 3,312 Malaysian primary school boys and girls, aged 6 to 11 years, belonging to various ethnic groups in Malaysia were measured. On the whole, the Chinese children were taller and heavier than the Malay and the Indian children who were the least heavy among the three ethnic groups. Economically the Indians were the poorest among the three ethnic groups and they also had the largest family size. When the household incomes were taken into consideration it was found that the growth achievement of the higher income children was better than that of the poorer children, irrespective of their ethnic groups. It is interesting to note that, although the Indian children as a whole, were the least heavy of the three ethnic groups, yet the growth achievement of the higher income Indian children was similar to that of the higher income Chinese children. The differences in growth achievement of the various ethnic groups are probably due to environmental differences, rather than genetic differences. It seems likely that Malaysian children of different ethnic groups (Malay, Chinese and Indian) can attain similar statures if environmental conditions are similar.

Fulltext Head circumference of Malaysian school children

Chen ST

Med J Malaysia, 1985 Jun;40(2):90-4.

PMID: 3834291

Percentile head circumference charts, from six to eleven years of age, for boys and girls are presented. These can be used to monitor the head circumference of Malaysian children.

Fulltext Growth charts based on longitudinal study of Malaysian children from birth to six years

Chen ST

Med J Malaysia, 1985 Jun;40(2):80-9.

PMID: 3834290

Percentile growth charts of weight, length and head circumference, from birth to six years of age, for boys and girls, are presented. These can be used to monitor the growth of Malaysian children.

Fulltext Optimum age for measles immunization in Malaysia

Chen ST, Lam SK

Med J Malaysia, 1985 Dec;40(4):281-8.

PMID: 3842727

A study was carried out at the University Hospital, Kuala Lumpur, Malaysia to determine the age-specific prevalence of measles infection by serology and the age specific - seroconversion rates following measles vaccination. The results show that the percentage of children with passively acquired measles antibodies decreased with increasing age fill three to five months of age. From 12 months of age, the percentage of positivity increased sharply due probably to natural infection. The geometric mean antibody titre was low at birth, but from six months it started to increase. These results indicate that measles infection is common in Malaysia and a small number of children began to acquire natural measles infection from six to eight months of age; however the peak age for the acquisition of measles infection was from 12 months to five years of age. Seroconversion rates following vaccination from nine months of age, ranged from 94-99%. However, the rates and the geometric mean titre were higher among those vaccinated at 11 months of age or older compared with those vaccinated at nine or ten months of age. Based on the above results, it is concluded that the optimum age for measles immunization in Malaysia should be 11 months.

Fulltext Breast feeding and hospital practices

Chen ST

Med J Malaysia, 1980 Jun;34(4):325-8.

PMID: 7219257

Prevalence of protein-calorie malnutrition in a group of Malaysian school children

Chen ST

Med J Malaysia, 1977 Jun;31(4):266-9.

PMID: 412037

Measles in peninsular Malaysia

Chen ST

Med J Malaysia, 1979 Sep;34(1):18-23.

PMID: 542144