Feasibility of T-Cell Receptor y (TCRy) Gene Rearrangement on Formalin-Fixed, Paraffin-Embedded Tissues by PCR Assays

Share this Article

Singapore Med J 2003; 44(5): 250-255
Feasibility of T-Cell Receptor y (TCRy) Gene Rearrangement on Formalin-Fixed, Paraffin-Embedded Tissues by PCR Assays

YC Tai, SC Peh
Correspondence: Prof S C Peh, pehsc@ummc.edu.my

ABSTRACT
Introduction
 T- and B-lymphocytes are involved in recognition of foreign antigen by the specificity of their surface T-cell receptor and immunoglobulin, generated by gene rearrangement. Each T- and B-lymphocyte carries unique rearranged TCR or immunoglobulin gene, which has been applied to detect clonal from non-clonal T- and B-cell proliferation.
Methods Paraffin-embedded biopsy tissues of 85 T-, 24 B-cell non-Hodgkin's lymphomas (NHL) of various subtypes, and seven reactive lymphoid hyperplasia were retrieved from the archives for determining the feasibility of TCRgamma gene rearrangement analysis by PCR assays in our laboratory. DNA was extracted by Proteinase K digestion. The analyses were performed by five PCR assays, and analysed on polyacrylamide gel.
Results Clonal TCRgamma gene rearrangement was demonstrated in 69/85 (81.2%) of the cases. Selective rearrangement of specific Vgamma segment was observed, especially in peripheral T-cell lymphoma-unspecified and nasal NK/T-cell lymphoma. Clonal TCRgamma rearranged band was also demonstrated in 4/24 (16.7%) and 2/7 (28.6%) of B-NHL and reactive lymphoid tissues respectively.
Conclusion PCR assays were able to demonstrate clonal TCRgamma gene rearrangement in a high proportion of T-NHL. However, the PCR results should be interpreted carefully. A neoplasm should only be considered as T-cell type if it does not express any B-cell marker because TCRgamma is not lineage specific as shown by the presence of clonal TCRgamma gene rearrangement in B-NHL. Hence, the results for TCR gene rearrangement should always be interpreted in conjunction with histology and immunophenotyping.

Keywords: TCRy gene rearrangement, paraffin-embedded tissues, NHL
Singapore Med J 2003; 44(5): 250-255

Different Types of Variable Decelerations and Their Effects to Neonatal Outcome

Share this Article

Singapore Med J 2003; 44(5): 243-247
Different Types of Variable Decelerations and Their Effects to Neonatal Outcome

Mert Kazandi, Fatih Sendag, Fuat Akercan, Mustafa Cosan Terek, Gursen Gundem
Correspondence: Dr Mert Kazandi, mkazandi@med.ege.edu.tr

ABSTRACT
Objective
 Although the only objective finding of intrapartum fetal distress is obtained through the measurement the fetal scalp pH, this invasive procedure is not available in every institution. The careful examination of fetal heart rate tracings for abnormalities, especially of the most commonly seen one, variable decelerations gains great importance under these circumstances. The aim of the present study is to determine the prognostic significance of variable decelerations in intrapartum fetal heart rate monitoring.
Methods A total of 96 fetal heart rate tracings were analysed to assess the prognostic significance of variable decelerations. Sixty-six percent (64/96) of cases exhibited atypia characterised with (1) slow return of the fetal heart rate to the baseline; (2) loss of variability during the decelerations; (3) loss of initial and/or secondary accelerations; (4) persistence of secondary acceleration (overshoot); and (5) continuation of the baseline fetal heart rate at a lower level; (6) biphasic deceleration. One and five-minute Apgar scores and umbilical artery pH were used to assess the final fetal condition.
Results Adverse fetal outcome characterised by fetal acidosis and Apgar score lower than 7 at one and five minutes were uncommon with pure variable decelerations. Typical and atypical variable decelerations were associated with low Apgar scores (< 7) at one minute in 9.3% and 54.6% of cases (p < 0.001) and at five minutes in 6.25% and 25% of cases (p < 0.05), respectively. In addition umbilical artery pH found to be lower than 7.2 in these cases ( 18.75% - p < 0.05). There was no danger for the fetal haemodynamic conditions when typical uterus contraction/variable deceleration ratios were two or more than two. However, risk of fetal hypoxia damage was quite high when this ratio was lower than two in atypical variable 5th minute low Apgar scores and pH (81.8% and 36.6% respectively). Atypical features are helpful in the identification of distress characterised by low Apgar scores in fetuses with variable decelerations. Admission to the neonatal intensive care unit was more common in patients with atypical variable decelerations in comparison with typical variable decelerations (34.3% versus 3.1%).
Conclusion While typical variable decelerations are frequently harmless, atypical variations pose a significant risk of fetal hypoxia.

Keywords: variable deceleration, neonatal outcome
Singapore Med J 2003; 44(5): 243-247

The Need for Drug and Poison Information - The Singapore Physicians' Perspective

Share this Article

Singapore Med J 2003; 44(5): 231-242
The Need for Drug and Poison Information - The Singapore Physicians' Perspective

R Ponampalam, V Anantharaman
Correspondence: R Ponampalam, gaerpo@sgh.com.sg

ABSTRACT
Introduction
 There appears to be a significant prevalence of poisoning and adverse drug reactions in Singapore. However, the resources needed by physicians to assist them in the management of such cases are limited. This study examines the information resources currently utilised by medical professionals in assisting them in the management of poisonings and adverse drug reactions. The preferred features of an ideal Drug and Poison Information Centre in the local setting were also explored.
Method A questionnaire survey involving all practicing physicians in Singapore to find out the current information resources utilised for Drug and Poison Information and the need for enhanced resources and its preferred form was looked at.
Results A total of 1,071 practicing physicians responded forming 24% of all physicians in Singapore as of December 1997. Of these, 636 (61.3%) were general practitioners and the rest specialists. The main sources of poison information were Drug Index of Malaysia and Singapore or DIMS (73.7%), standard textbooks (70.1%), fellow colleagues (44.6%) and pharmacists (41.0%). In the opinion of most (82.4%), one well run and efficient Drug and Poison Information Centre was adequate for the whole island. The majority (58.9%) preferred that experienced individuals who could be consulted upon in times of need man such a service.
Conclusion The study shows the need for enhanced drug and poison information resources. The local physician community also expects guidance and expert advice from a specialist. With this in mind, it is worthwhile examining in depth the issues surrounding poison and adverse drug reaction management and the need for readily accessible Drug and Poison Information resources in Singapore.

Keywords: poison information centre, drug information service, adverse drug reactions, poisoning
Singapore Med J 2003; 44(5): 231-242

Emotional and behavioural problems in Singaporean children based on parent, teacher and child reports

Share this Article

Singapore Med J 2007; 48(12): 1100-1106
Emotional and behavioural problems in Singaporean children based on parent, teacher and child reports

Woo BSC, Ng TP, Fung DSS, Chan YH, Lee YP, Koh JBK, Cai Y
Correspondence: Dr Bernardine SC Woo, bernardine_woo@imh.com.sg

ABSTRACT
Introduction
 This study aims to determine the prevalence of emotional and behavioural problems in a community sample of Singaporean children aged 6-12 years, and its agreement according to parent, teacher and child reports.
Methods The Child Behaviour Checklist (CBCL), Teacher Rating Form (TRF) and child report questionnaires for depression and anxiety were administered to a community sample of primary school children. 60 percent of the children sampled (n = 2,139) agreed to participate. Parents of a sub-sample of 203 children underwent a structured clinical interview.
Results Higher prevalence of emotional and behavioural problems was identified by CBCL (12.5 percent) than by TRF (2.5 percent). According to parent reports, higher rates of internalising problems (12.2 percent) compared to externalising problems (4.9 percent), were found. Parent-teacher agreement was higher for externalising problems than for internalising problems. Correlations between child-reported depression and anxiety, and parent and teacher reports were low to moderate, but were better for parent reports than for teacher reports.
Conclusion The prevalence rates of emotional and behavioural problems in Singaporean children based on CBCL ratings are comparable to those in the West, but the low response rate and exclusion of children with special needs limit the generalisability of our findings. Singaporean children have higher rates of internalising problems compared to externalising problems, while Western children have higher rates of externalising problems compared to internalising problems.

Keywords: behavioural problems, childhood mental health, childhood problems, emotional problems
Singapore Med J 2007; 48(12): 1100–1106