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Transcriptional profiling of oral squamous cell carcinoma using formalin-fixed paraffin-embedded samples

Saleh A, Zain RB, Hussaini H, Ng F, Tanavde V, Hamid S, et al.

Oral Oncol, 2010 May;46(5):379-86.
PMID: 20371203 DOI: 10.1016/j.oraloncology.2010.02.022

Despite the advances in cancer treatment, the 5-year survival rate for oral cancer has not changed significantly for the past 40 years and still remains among the worst of all anatomic sites. Gene expression microarrays have been used successfully in the identification of genetic alterations in cancer development, however, these have hitherto been limited by the need for specimens with good quality intact RNA. Here, we demonstrated the use of formalin-fixed paraffin-embedded tissues in microarray experiments to identify genes differentially expressed between cancerous and normal oral tissues. Forty-three tissue samples were macrodissected and gene expression analyses were conducted using the Illumina DASL assay. We report RNA yield of 2.4 and 0.8 microg/mm(3) from tumour and normal tissues, respectively and this correlated directly with the tissue volume used for RNA extraction. Using unsupervised hierarchical clustering, distinct gene expression profiles for tumour and normal samples could be generated, and differentially expressed genes could be identified. The majority of these genes were involved in regulation of apoptosis and cell cycle, metastasis and cell adhesion including BCL2A1, BIRC5, MMP1, MMP9 and ITGB4. Representative genes were further validated in independent samples suggesting that these genes may be directly associated with oral cancer development. The ability to conduct microarrays on formalin-fixed paraffin-embedded specimens represents a significant advancement that could open up avenues for finding genes that could be used as prognostication and predictive tools for cancer.
The thiamine content of human milk in Malaya. II. The effect of the administration of supplementary thiamine on the thiamine level of human milk

Chow AY, Simpson IA

J Trop Pediatr (Lond), 1956 Sep;2(2):69-76.
PMID: 24544134

(1) The effect has been studied of the oral administration of supplementary thiamine on the thiamine content of milk from sixteen women, whose initial thiamine content was low ; and of the parenteral administration of thiamine to ten women, some of whom initially showed mild, clinical symptoms of beriberi.
(2) The response in the milk content of thiamine to supplementary thiamine, administered either orally or by injection, showed marked variation in different women. While comparatively small doses taken by mouth evoked a marked response in some women, fairly large doses administered by injection failed to produce much response in others.
(3) In some women, a marked increase in the thiamine content of their milk occurred soon after the administration of thiamine, either orally or parenterally. In others, the response was slow and meagre.
(4) The highest thiamine level obtained in a sample of milk was 38.9 ug./100 ml., after the injection, twice daily, of 20 mg. thiamine for six days — a total intake of 240 mg. of thiamine parenterally. The initial milk thiamine level in this case was 2.3 ug./100 ml., but had increased to 16.2ug./100 ml., by the supply of a good diet alone, before the course of injections was commenced.
(5) It would appear, that, in cases where the thiamine content of the milk is low, initial parenteral administration of thiamine must be supplemented by a continued intake of additional thiamine, if a satisfactory level of thiamine in the milk is to be maintained.
The thiamine content of human milk in Malaya. I. The normal level of thiamine in milk from Malay, Chinese and Indian women

Simpson IA, Chow AY

J Trop Pediatr (Lond), 1956 Jun;2(1):3-17.
PMID: 24544028 DOI: 10.1093/oxfordjournals.tropej.a057405

(1) The use of the thiochrome method for the estimation of thiamine in human milk is discussed, with special reference to the possible production of an artefact, following the incubation of the milk with pepsin, in addition to the use of takadiastase (clarase). No evidence could be found to suggest that an artefact resembling thiamine was produced by the method of analysis described.
(2) The thiamine content of 91 samples of full lactation human milk from apparently "normal" Malay, Chinese and Indian women in Malaya is recorded. The mean milk thiamine level of 11.3 ug/100 ml. found is considerably lower than the levels recorded for milk samples from apparently "normal " women in the United Kingdom and the U.S.A.; and slightly lower than that recorded in Australia. The results suggest that the dietary
intake of thiamine in Malaya is inadequate to maintain optimum thiamine levels in the milk of lactating women.
(3) No significant difference was found in the mean thiamine content of milk from women of the three principal racial groups in Malaya ; nor was any significant difference found to be associated with the parity or age of the women or, in the case of full lactation milks, with the time after parturition at which the sample was collected. No significant difference was found in samples collected from the same woman at different times of the day or before and after a main meal.
(4) Marked differences were found in the thiamine content of samples of milk from individual women, and the possible reasons for this are discussed.
(5) The examfnation of 48 samples of milk collected during the first month after parturition confirmed previous recorded observations that the thiamine content of such milks, initially low, gradually increases to reach "normal" levels towards the end of the first month of lactation.
Fulltext Seroprevalence of IgG antibodies against diphtheria antitoxin among migrant workers in Singapore, 2016-2019

Ang LW, Gao Q, Cui L, Farwin A, Toh MPHS, Boudville IC, et al.

BMC Public Health, 2022 Jan 16;22(1):111.
PMID: 35033034 DOI: 10.1186/s12889-022-12528-y

BACKGROUND: Since the last local case of diphtheria in 1992, there had not been any case in Singapore until an autochthonous case was reported in 2017. This fatal diphtheria case of a migrant worker raised concerns about the potential re-emergence of locally transmitted toxigenic diphtheria in Singapore. We conducted a seroprevalence study to assess the immunity levels to diphtheria among migrant workers in Singapore.
METHODS: Residual sera from migrant workers who hailed from Bangladesh, China, India, Indonesia, Malaysia, Myanmar and the Philippines were tested for anti-diphtheria toxoid immunoglobulin G (IgG) antibodies. These migrant workers previously participated in a survey between 2016 and 2019 and had provided blood samples as part of the survey procedure.
RESULTS: A total of 2176 migrant workers were included in the study. Their overall mean age was 27.1 years (standard deviation 5.0), range was 20-43 years. The proportion having at least basic protection against diphtheria (antitoxin titres ≥ 0.01 IU/ml) ranged from 77.9% (95% confidence interval [CI] 72.8 - 82.3%) among migrant workers from Bangladesh to 96.7% (95% CI 92.5 - 98.6%) in those hailing from Malaysia. The proportion showing full protection (antitoxin titres ≥ 0.10 IU/ml) ranged from 10.1% (95% CI 6.5 - 15.4%) in Chinese workers to 23.0% (95% CI 17.1 - 30.3%) in Malaysian workers. There were no significant differences in the proportion with at least basic protection across birth cohorts, except for those from Bangladesh where the seroprevalence was significantly lower in younger migrant workers born after 1989.
CONCLUSIONS: The proportions having at least basic protection against diphtheria in migrant workers from five out of seven Asian countries (India, Indonesia, Malaysia, Myanmar and the Philippines) were higher than 85%, the threshold for diphtheria herd immunity. Seroprevalence surveys should be conducted periodically to assess the level of immunity against diphtheria and other vaccine preventable diseases in migrant worker population, so that appropriate interventions such as booster vaccination can be implemented proactively to prevent sporadic outbreaks.
Fulltext Prevalence of measles antibodies among migrant workers in Singapore: a serological study to identify susceptible population subgroups

Ang LW, Gao Q, Cui L, Farwin A, Toh MPHS, Boudville IC, et al.

BMC Infect Dis, 2022 Jan 25;22(1):88.
PMID: 35078426 DOI: 10.1186/s12879-022-07066-2

BACKGROUND: In 2019, two clusters of measles cases were reported in migrant worker dormitories in Singapore. We conducted a seroprevalence study to measure the level of susceptibility to measles among migrant workers in Singapore.
METHODS: Our study involved residual sera of migrant workers from seven Asian countries (Bangladesh, China, India, Indonesia, Malaysia, Myanmar and the Philippines) who had participated in a survey between 2016 and 2019. Immunoglobulin G (IgG) antibody levels were first measured using a commercial enzyme-linked immunosorbent assay (ELISA) test kit. Those with equivocal or negative IgG results were further evaluated using plaque reduction neutralization test (PRNT).
RESULTS: A total of 2234 migrant workers aged 20-49 years were included in the study. The overall prevalence of measles IgG antibodies among migrant workers from the seven Asian countries was 90.5% (95% confidence interval 89.2-91.6%). The country-specific seroprevalence ranged from 80.3 to 94.0%. The seroprevalence was significantly higher among migrant workers born in 1965-1989 than those born in 1990-1999 (95.3% vs. 86.6%, p
Influenza B outbreak among influenza-vaccinated welfare home residents in Singapore

Win MK, Chow A, Chen M, Lau YF, Ooi EE, Leo YS

Ann Acad Med Singap, 2010 Jun;39(6):448-52.
PMID: 20625620

INTRODUCTION: Outbreaks of acute respiratory illness occur commonly in long-term care facilities (LTCF), due to the close proximity of residents. Most influenza outbreak reports have been from temperate countries. This study reports an outbreak of influenza B among a highly immunised resident population in a welfare home in tropical Singapore, and discusses vaccine efficacy and the role of acute respiratory illness surveillance for outbreak prevention and control.
MATERIALS AND METHODS: During the period from 16 to 21 March 2007, outbreak investigations and active case finding were carried out among residents and nursing staff at the welfare home. Interviews and medical notes review were conducted to obtain epidemiological and clinical data. Hospitalised patients were tested for respiratory pathogens. Further genetic studies were also carried out on positive respiratory samples.
RESULTS: The overall clinical attack rate was 9.4% (17/180) in residents and 6.7% (2/30) in staff. All infected residents and staff had received influenza immunisation. Fifteen residents were hospitalised, with 2 developing severe complications. Genetic sequencing revealed that the outbreak strain had an 8.2% amino acid difference from B/Malaysia/2506/2004, the 2006 southern hemisphere influenza vaccine strain, which the residents and staff had earlier received.
CONCLUSIONS: A mismatch between the vaccine and circulating influenza virus strains can result in an outbreak in a highly immunised LTCF resident population. Active surveillance for acute respiratory illness in LTCFs could be implemented for rapid detection of antigenic drift. Enhanced infection control and other preventive measures can then be deployed in a timely manner to mitigate the effect of any outbreaks.
Fulltext Early clearance of Chikungunya virus in children is associated with a strong innate immune response

Simarmata D, Ng DC, Kam YW, Lee B, Sum MS, Her Z, et al.

Sci Rep, 2016 05 16;6:26097.
PMID: 27180811 DOI: 10.1038/srep26097

Chikungunya fever (CHIKF) is a global infectious disease which can affect a wide range of age groups. The pathological and immunological response upon Chikungunya virus (CHIKV) infection have been reported over the last few years. However, the clinical profile and immune response upon CHIKV infection in children remain largely unknown. In this study, we analyzed the clinical and immunological response, focusing on the cytokine/chemokine profile in a CHIKV-infected pediatric cohort from Sarawak, Malaysia. Unique immune mediators triggered upon CHIKV infection were identified through meta-analysis of the immune signatures between this pediatric group and cohorts from previous outbreaks. The data generated from this study revealed that a broad spectrum of cytokines/chemokines is up-regulated in a sub-group of virus-infected children stratified according to their viremic status during hospitalization. Furthermore, different immune mediator profiles (the levels of pro-inflammatory cytokines, chemokines and growth and other factors) were observed between children and adults. This study gives an important insight to understand the immune response of CHIKV infection in children and would aid in the development of better prognostics and clinical management for children.
Fulltext Clinical features and epidemiology of chikungunya infection in Singapore

Ng KW, Chow A, Win MK, Dimatatac F, Neo HY, Lye DC, et al.

Singapore Med J, 2009 Aug;50(8):785-90.
PMID: 19710977

Chikungunya is a re-emerging mosquito-borne viral infection that has spread from East Africa to Indian Ocean islands and re-emerged in India since 2004. In Malaysia, chikungunya re-emerged after a hiatus of seven years, causing a localised outbreak in a north-western coastal town in 2006 and subsequently widespread outbreaks in 2008. Since the first local outbreak of chikungunya in Singapore in January 2008, chikungunya infections have been increasingly reported in Singapore. In this case series, five patients aged 37-62 years, with chikungunya infection confirmed in August 2008, were reported. Three of the five were male, and only one had medical comorbidities. Two had a travel history to Johor, Malaysia, where local outbreaks of chikungunya had been reported. Fever, arthralgia and rash were the most common symptoms. Fever lasted four to five days while viraemia lasted four to 11 days, persisting two to three days after defervescence in three patients. A biphasic pattern of fever was observed in two patients. Leucopenia was noted in all patients, while mild thrombocytopenia and transaminitis occurred in three of five patients. Two patients had persistent polyarthralgia at two to three weeks after the onset of symptoms. Fever, arthralgia and rash should prompt consideration of acute chikungunya in Singapore. While taking the travel history, doctors should be mindful that indigenous chikungunya cases can occur.