The effect of a forced-air warming blanket on patients' end-tidal and transcutaneous carbon dioxide partial pressures during eye surgery under local anaesthesia: a single-blind, randomised controlled trial.

Surgical drapes used during eye surgery are impermeable to air and hence risk trapping air underneath them. We investigated the effect of a forced-air warming blanket on carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia without sedation. Forty patients of ASA physical status 1 and 2 were randomly assigned to either the forced-air warmer (n = 20) or a control heated overblanket (n = 20). All patients were given 1 l.min(-1) oxygen. We measured transcutaneous and end-tidal carbon dioxide partial pressures, heart rate, arterial pressure, respiratory rate, temperature and oxygen saturation before and after draping, then every 5 min thereafter for 30 min. The mean (SD) transcutaneous carbon dioxide partial pressure in the forced-air warming group stayed constant after draping at 5.7 (0.2) kPa but rose to a maximum of 6.4 (0.4) kPa in the heated overblanket group (p = 0.0001 for the difference at time points 15 min and later). We conclude that forced-air warming reduces carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia.

Second and third year oral health and dental student perceptions of future professional work.

OBJECTIVES: To explore and compare the ways dental and oral health students characterise their future professional work (FPW) at the end of their second and third professional years. MATERIALS AND METHODS: Questionnaires were given to a cohort group of 48 dental students and 31 oral health students at the end of their second and third professional years at the University of Otago. Students' characterisations of their FPW were identified using an inductive approach, and the emphasis on each characterisation was confirmed using a 'weighted' table. RESULTS: Dental student response rates were 92% (in 2010) and 85% (in 2011); and oral health student response rates were 100% (in 2011) and 97% (in 2011). Students characterised their FPW in ten broad ways: in reference to treatment-related concerns, patient-related concerns, oral health promotion, oral health education, disease prevention and monitoring, communication, teamwork, maintaining an ideal clinical environment, maintaining a sense of self and improving quality of life. In both years, dental students emphasised treatment-related concerns as central to their FPW and dealing with patient-related concerns as a primary source of difficulty. Oral health students emphasised oral health promotion, oral health education, disease prevention and monitoring and restorative tasks as central to their FPW and dealing with patient-related concerns as a primary source of difficulty. CONCLUSION: Students' broad perceptions of their FPW changed little as they progressed through their programmes; however, their responses suggested the need for greater attention within their programmes to patient management and teamwork.

Efficacy of iontophoresis with glycopyrronium bromide for treatment of primary palmar hyperhidrosis.

BACKGROUND: There is limited data on the efficacy of iontophoretic treatment of primary palmar hyperhidrosis using glycopyrronium bromide. The first line treatment for primary palmar hyperhidrosis is usually topical aluminium chloride, but clinical experience indicates that it is not effective for more severe disease. OBJECTIVE: To evaluate the efficacy of using glycopyrronium bromide iontophoresis in the treatment of primary palmar hyperhidrosis, and to evaluate if the benefit of treatment varies with the severity of disease. METHODS: This is an open-label study involving patients undergoing weekly treatment of iontophoresis with glycopyrronium bromide for 4 weeks. Gravimetric measurements of sweat production and subjective scores of palmar sweatiness were recorded prior to starting treatment and 1 week after the last treatment. Side-effects were monitored weekly. RESULTS: Twenty two of the 25 patients recruited completed the 4-week treatment. There was a significant mean improvement of 23.4 mg/min (P = 0.001) between baseline and post-treatment gravimetric measurements. Patients with a higher baseline sweat output demonstrated a trend towards a greater reduction in sweat production (Pearson's correlation correlation coefficient, r = 0.41). The patients experienced dryness of the palms for a mean duration of 5 days after iontophoresis. All patients reported an improvement in satisfaction scores and 81.8% reported an improvement in subjective severity scores. No serious side-effects were encountered during the study. CONCLUSIONS: Iontophoresis using glycopyrronium bromide is an effective and well-tolerated treatment for primary palmar hyperhidrosis. The possibility of its greater benefit in patients with more severe baseline disease requires verification.

Rapid aneuploidy screening with fluorescence in-situ hybridisation: is it a sufficiently robust stand-alone test for prenatal diagnosis?

OBJECTIVES: To assess the clinical utility of fluorescence in-situ hybridisation with chromosomes 13, 18, 21, X and Y as a stand-alone test in detecting chromosomal abnormalities, and the types of chromosomal abnormalities missed. DESIGN: Retrospective analysis. SETTING: A restructured Government hospital in Singapore and an academic hospital in the United States. PARTICIPANTS: Cytogenetic data of prenatal specimens and results of fluorescence in-situ hybridisation of 5883 patients performed between January 2000 and August 2007 were reviewed. RESULTS: Fluorescence in-situ hybridisation detected 558 (9.5%) patients with chromosomal abnormalities. Abnormal ultrasounds (70%) and maternal serum screens (21%) were the most indicative of chromosomal abnormalities. When comparing fluorescence in-situ hybridisation data with karyotype results for the five chromosomes of interest, the sensitivity and specificity were 99.3% and 99.9%, respectively. When comparing fluorescence in-situ hybridisation data with karyotype results for all chromosomes, the sensitivity decreased to 86.8%, whereas the specificity remained at 99.9%. Of 643 cases with karyotype abnormalities, 85 were fluorescence in-situ hybridisation-negative (false negative rate, 13.2%), which included structural rearrangements, chromosome mosaicism, and other trisomies. Despite abnormal ultrasound indications, fluorescence in-situ hybridisation missed 32 cases which included structural rearrangements, mosaicisms, and other trisomies. CONCLUSION: This study does not support fluorescence in-situ hybridisation as a stand-alone test. Institutions supporting fluorescence in-situ hybridisation as a stand-alone test must seriously consider the risks of a missed diagnosis.

Single-tube tetradecaplex panel of highly polymorphic microsatellite markers < 1 Mb from F8 for simplified preimplantation genetic diagnosis of hemophilia A.

Essentials Preimplantation genetic diagnosis (PGD) of severe hemophilia A relies on linkage analysis. Simultaneous multi-marker screening can simplify selection of informative markers in a couple. We developed a single-tube tetradecaplex panel of polymorphic markers for hemophilia A PGD use. Informative markers can be used for linkage analysis alone or combined with mutation detection. SUMMARY: Background It is currently not possible to perform single-cell preimplantation genetic diagnosis (PGD) to directly detect the common inversion mutations of the factor VIII (F8) gene responsible for severe hemophilia A (HEMA). As such, PGD for such inversion carriers relies on indirect analysis of linked polymorphic markers. Objectives To simplify linkage-based PGD of HEMA, we aimed to develop a panel of highly polymorphic microsatellite markers located near the F8 gene that could be simultaneously genotyped in a multiplex-PCR reaction. Methods We assessed the polymorphism of various microsatellite markers located ≤ 1 Mb from F8 in 177 female subjects. Highly polymorphic markers were selected for co-amplification with the AMELX/Y indel dimorphism in a single-tube reaction. Results Thirteen microsatellite markers located within 0.6 Mb of F8 were successfully co-amplified with AMELX/Y in a single-tube reaction. Observed heterozygosities of component markers ranged from 0.43 to 0.84, and ∼70-80% of individuals were heterozygous for ≥ 5 markers. The tetradecaplex panel successfully identified fully informative markers in a couple interested in PGD for HEMA because of an intragenic F8 point mutation, with haplotype phasing established through a carrier daughter. In-vitro fertilization (IVF)-PGD involved single-tube co-amplification of fully informative markers with AMELX/Y and the mutation-containing F8 amplicon, followed by microsatellite analysis and amplicon mutation-site minisequencing analysis. Conclusions The single-tube multiplex-PCR format of this highly polymorphic microsatellite marker panel simplifies identification and selection of informative markers for linkage-based PGD of HEMA. Informative markers can also be easily co-amplified with mutation-containing F8 amplicons for combined mutation detection and linkage analysis.

Binding of monoclonal antibodies that inhibit spleen colony formation to leukemic cell lines.

Clonogenic tumor cells and normal stem cells share the property of extensive proliferative potential. Normal stem cells are under stringent growth restraint and respond to appropriate differentiation signals, whereas tumor stem cells have lost the ability to respond normally to these controls. In an attempt to define cell surface molecules involved in the control of hemopoietic cell proliferation and differentiation, we have produced 5 monoclonal antibodies against antigens held in common between hemopoietic stem cells and the Abelson virus-induced pre-B-lymphoma cells from which they were derived. Four of these monoclonal antibodies produced greater than 90% reduction of spleen colony-forming cells, whereas the other bound to a subpopulation (60 to 70%) of spleen colony-forming cells at plateau values. The expression of antigens recognized by these and two other anti-stem cell monoclonal antibodies has been shown to correlate with the differentiation status of a panel of tumor cell lines, with greater expression being observed on cells more closely resembling the pluripotent stem cell than mature hemopoietic cells. Immunoperoxidase staining of bone marrow showed that these antigens are mainly expressed by monocytes and blast cells. Treatment of bone marrow cells with those antibodies which extensively inhibited spleen colony formation and with rabbit complement abolished the ability of progenitor cells to form colonies in soft agar. Quantitative absorption studies distinguished the antigens recognized by two of the anti-stem cell monoclonal antibodies from those detected by anti-H-2k 11-4.1 monoclonal antibody. These observations suggest that the antigens involved may play a role in the regulation of growth and differentiation of stem cells and undifferentiated leukemic cells.

Array comparative genomic hybridisation analysis of boys with X linked hypopituitarism identifies a 3.9 Mb duplicated critical region at Xq27 containing SOX3.

INTRODUCTION: Array comparative genomic hybridisation (array CGH) is a powerful method that detects alteration of gene copy number with greater resolution and efficiency than traditional methods. However, its ability to detect disease causing duplications in constitutional genomic DNA has not been shown. We developed an array CGH assay for X linked hypopituitarism, which is associated with duplication of Xq26-q27. METHODS: We generated custom BAC/PAC arrays that spanned the 7.3 Mb critical region at Xq26.1-q27.3, and used them to search for duplications in three previously uncharacterised families with X linked hypopituitarism. RESULTS: Validation experiments clearly identified Xq26-q27 duplications that we had previously mapped by fluorescence in situ hybridisation. Array CGH analysis of novel XH families identified three different Xq26-q27 duplications, which together refine the critical region to a 3.9 Mb interval at Xq27.2-q27.3. Expression analysis of six orthologous mouse genes from this region revealed that the transcription factor Sox3 is expressed at 11.5 and 12.5 days after conception in the infundibulum of the developing pituitary and the presumptive hypothalamus. DISCUSSION: Array CGH is a robust and sensitive method for identifying X chromosome duplications. The existence of different, overlapping Xq duplications in five kindreds indicates that X linked hypopituitarism is caused by increased gene dosage. Interestingly, all X linked hypopituitarism duplications contain SOX3. As mutation of this gene in human beings and mice results in hypopituitarism, we hypothesise that increased dosage of Sox3 causes perturbation of pituitary and hypothalamic development and may be the causative mechanism for X linked hypopituitarism.

Cyclic adenosine monophosphate promotes cell survival and retards apoptosis in a factor-dependent bone marrow-derived cell line.

Hemopoietic growth factors promote cell survival, proliferation and differentiation, but whether these processes, which often occur in concert, are mediated through the same or different receptor signaling mechanisms is not known. Using the bone marrow-derived IL-3-dependent cell line, 32D, we show that dibutyryl cyclic adenosine monophosphate (dbcAMP) retards the rapid loss of viable cells seen in the absence of IL-3. This effect is shown to be concentration-dependent and detectable within 16 hours of culture and is not associated with cell differentiation. At earlier times (2 to 7 hours), when no significant changes in cell numbers were observed, dbcAMP stimulated the reduction of dimethylthiazoldiphenyl tetrazolium bromide (MTT), and this effect was indistinguishable from that seen with IL-3. In contrast, control cells deprived of growth factor showed a decline in MTT response over this period. The effect of dbcAMP in maintaining cell viability and MTT responsiveness was associated with a concentration-dependent inhibition of 3H-thymidine incorporation into DNA, and retardation of the intranucleosomal cleavage of DNA that is associated with apoptosis. These results suggest that in 32D cells, cAMP can act to promote cell survival and retard apoptosis, quite independently of cell proliferation, by stimulating the activity of mitochondrial enzymes involved in MTT reduction.

Changes in cell surface antigens during stem cell ontogeny.

A panel of monoclonal antibodies that bind to the murine pluripotential stem cell CFU-s was used to examine the antigenic profile of the stem cell during ontogeny. The results show that the stem cell surface changes dramatically during development. One group of three independently derived monoclonal antibodies binds to subpopulations (50%-70%) of stem cells at plateau values, and these populations increase marginally during development. A second group of four monoclonal antibodies, including anti-H-2Kk (11-4.1), define stem cell antigens that increase from low levels in the fetal liver to high levels in adult bone marrow. The presence of these two classes of antigens on adult splenic stem cells was in general similar to that observed on adult bone marrow. Antigens defined by the first group of monoclonal antibodies were present in similar amounts on CBA, C57B1/6, and Balb/c bone marrow stem cells, whereas antigens of the second group showed mouse strain variations. Quantitative absorption analysis was used to distinguish H-2Kk (11-4.1) from 9F6, which showed a similar developmental profile. Monoclonal antibodies recognizing subpopulations of stem cells were shown to be distinct by complementation studies and recognized antigens not present on brain tissue.

Monoclonal antibodies that bind to hemopoietic stem cells: characterization and immunohistochemical localization of cells expressing gp50-65.

The cell surface of hemopoietic stem cells has been shown to express several antigens in common with more mature hemopoietic cells. One set of stem cell antigens is defined by a group of three monoclonal antibodies (13C6, 1C10, and 1A9), selected on the basis of binding to subpopulations of spleen colony-forming stem cells (CFU-S). These antibodies are shown to recognize cell surface glycoproteins of 50-65 kd (gp50-65) that occur widely on hemopoietic cells. Each cell type investigated shows a distinctive pattern of expression of these glycoproteins. To further investigate the presence of gp50-65 on stem cells, low-density bone marrow cells were labeled with 1C10 and sorted according to fluorescence intensity. Most (73%) of the stem cells (CFU-S10) were recovered in the two most highly fluorescent fractions containing 2.6% of starting marrow cells. Immunohistochemistry of frozen sections of normal spleen and spleens during repopulation after lethal irradiation and bone marrow transplantation showed that the most strongly 1C10-labeled cells occurred under the splenic capsule and along trabeculae. Although many of these cells were also alpha-naphthylacetate esterase positive and Mac-1 positive, indicating cells of the monocyte-macrophage lineage, a distinctive population of singular cells were stained with 1C10 alone. These cells were negative for surface Ig and closely corresponded with a small population of cells in a similar location that were doubly labeled with 1C10 and anti-Thy-1. These results show that stem cells express high levels of gp50-65 and suggest that stem cells can be identified by immunohistochemical methods using dual labeling procedures.

Expression of specific high-affinity binding sites for erythropoietin on rat and mouse megakaryocytes.

Considerable experimental and clinical evidence suggests a relationship between erythropoiesis and thrombopoiesis. This is supported by observations that erythropoietin (Epo), the primary regulator of erythropoiesis, can affect platelet production when injected into animals. In this study we provide experimental evidence for a direct effect of Epo on thrombopoiesis by demonstrating that 125I-labeled recombinant human Epo binds to rat and mouse bone marrow megakaryocytes. Thus, autoradiographic analysis using cold competition to measure specific binding has been used to demonstrate that Epo binding to megakaryocytes increases with megakaryocyte maturation. When corrected for cell size, Epo binding sites per unit surface area increase from Stage I megakaryoblasts to Stage II megakaryocytes, and then remain approximately constant throughout further megakaryocyte maturation. Receptor density on megakaryocytes is similar to that on pronormoblasts in the rat, and in mice is 60% that on pronormoblasts. No binding of Epo to platelets or to naked megakaryocyte nuclei was detected. Equilibrium binding studies with partially purified rat megakaryocytes (20%-40% pure), where megakaryocytes are the only significant Epo binding cell population, showed a single class of saturable, high-affinity binding sites present on average at 6500 binding sites per megakaryocyte with a KD of 287 pM. Binding of [125I]Epo to rat megakaryocytes was inhibited with an antiserum against murine erythroblasts. These results suggest that the effects of Epo on thrombopoiesis may be directly mediated through specific, high-affinity binding sites for Epo on the surface of maturing megakaryocytes.

High-capacity redox control at the plasma membrane of mammalian cells: trans-membrane, cell surface, and serum NADH-oxidases.

The high capacity of proliferating mammalian cells to transfer electrons from cytosolic NADH to extracellular electron acceptors like oxygen is poorly understood and not widely recognized. Nevertheless, trans-plasma membrane electron transport (plasma membrane redox control) probably ranks alongside the Na+/H+ antiport system (pH control) and glucose transport in facilitating cellular responses to physiological stimuli. These plasma membrane transport systems are acutely responsive to receptor ligation by growth factors, polypeptide hormones, and other cell activators. A novel tetrazolium-based cell proliferation assay that we have shown to measure an NADH-oxidoreductase component of the trans-plasma membrane electron transport system has allowed direct comparisons with NADH:ferricyanide-oxidoreductase and respiratory burst NADPH-oxidoreductase. In addition, an NAD(P)H-oxidase at the cell surface and an NADH-oxidase activity in body fluids can be measured by modifying the basic cell proliferation assay. As determined by reduction of the cell-impermeable tetrazolium reagent, WST-1, electron transfer across the plasma membrane of dividing cells can exceed that of fully activated human peripheral blood neutrophils. Cellular reduction of WST-1 is dependent on the presence of an intermediate electron acceptor and is inhibited by superoxide dismutase (SOD) and by oxygen, implying indirect involvement of superoxide in WST-1 reduction. Cell-surface NAD(P)H-oxidase and serum NADH-oxidase are shown to be distinct from trans-plasma membrane NADH-oxidoreductase by their differential sensitivity to capsaicin and pCMBS. The glycolytic metabolism of cancer cells may be linked to changes in trans-plasma membrane NADH:WST-1-oxidoreductase activity and to increased serum NADH-oxidase in cancer.

Cell-surface NAD(P)H-oxidase: relationship to trans-plasma membrane NADH-oxidoreductase and a potential source of circulating NADH-oxidase.

The surface of mammalian cells faces an oxidizing environment that has the potential to damage proteins, lipids, and carbohydrates to which it is exposed. In contrast, the cytoplasm is reducing and its redox state is tightly regulated. Trans-plasma membrane oxidoreductases that shift electrons from cytosolic NADH to external electron acceptors such as oxygen are widely involved in cellular redox control. They reduce oxygen to water and may generate reactive oxygen species such as superoxide and hydrogen peroxide. In addition, external NAD(P)H-oxidases have been demonstrated on intact cells and as eluted proteins, but the relationship between trans-plasma membrane NADH-oxidoreductases and cell-surface NAD(P)H-oxidases is not known. To investigate further the relationship between plasma membrane NAD(P)H-oxidoreductases, and to gain insight into the physiological functions of these redox active membrane proteins, we have adapted a simple colorimetric assay for measuring the trans-plasma membrane NADH-oxidoreductase activity of viable cells to measure NAD(P)H-oxidase at the cell surface in real time. Using the cell-impermeable tetrazolium salt WST-1 in the presence of NADH or NADPH, but in the absence of an intermediate electron acceptor, we show that cell-surface NAD(P)H-oxidase is widely expressed on mammalian cells, being more abundant on rapidly proliferating cells than on resting neutrophils and spleen cells. The ratio of cofactor dependence of NAD(P)H-oxidase (NADH:NADPH) varied widely between different cells (0.7-5.2), suggesting a family of cell surface oxidases or that the activity of these enzymes may be modulated in various ways. Comparison of NAD(P)H-oxidase on the surface of viable cells with trans-membrane NADH-oxidoreductase, measured with WST-1 in the presence of 1-methoxy PMS, showed that cell-surface NAD(P)H-oxidase was differentially inhibited by the cell-impermeable thiol-blocking agent pCMBS, but was unaffected or stimulated by other thiol blocking agents. Capsaicin, which inhibits trans-plasma membrane NADH-oxidoreductase activity, stimulated surface NAD(P)H-oxidase. Metabolic inhibitors had little effect on surface NAD(P)H-oxidase activity but inhibited trans-plasma membrane activity. These results do not support the view the surface NAD(P)H-oxidase is a terminal oxidase for trans-plasma membrane NADH-oxidoreductase.

Superoxide produced by activated neutrophils efficiently reduces the tetrazolium salt, WST-1 to produce a soluble formazan: a simple colorimetric assay for measuring respiratory burst activation and for screening anti-inflammatory agents.

Activation of the respiratory burst of granulocytes and macrophages by invading microorganisms is a key first line cellular defence against infection. Failure to generate this response leads to persistent life-threatening infection unless appropriate antibiotic treatment is given. The respiratory burst of neutrophils is usually measured spectrophotometrically by following ferricytochrome c reduction, and histologically by using the tetrazolium salt, nitroblue tetrazolium, which is reduced intracellularly to an insoluble formazan. In both assays, reduction is mediated by superoxide generated via NADPH oxidase. Because ferricytochrome c has a high molecular mass and high background absorbance at 550 nm, the assay lacks sensitivity and is not ideally suited to microplate measurement. We have circumvented these limitations by using the cell-impermeable, sulfonated tetrazolium salt, WST-1, which exhibits very low background absorbance and is efficiently reduced by superoxide to a stable water-soluble formazan with high molar absorptivity. This has permitted adaptation of the WST-1 assay to microplate format while retaining sensitivity. Reduction of WST-1 by activated human peripheral blood neutrophils correlated closely with ferricytochrome c reduction across a range of PMA concentrations and with time of activation by PMA and fMLP. Reduction of WST-1 was inhibited by 98% by superoxide dismutase (20 microg/ml) and by 88% by the NADPH oxidase inhibitor, diphenyleneiodinium (10 microM) but was resistant to catalase, azide and the NADH oxidase inhibitor, resiniferatoxin. WST-1 and ferricytochrome c reduction were also compared using xanthine/xanthine oxidase to generate superoxide. Under optimised assay conditions, both WST-1 and ferricytochrome c reduction were directly proportional to added xanthine. WST-1 generated approximately 2-fold greater increase in absorbance than ferricytochrome c at their respective wavelengths, and this translated into increased assay sensitivity. Addition of the intermediate electron acceptor, 1-methoxy phenazine methosulfate, increased the background of the neutrophil assay but did not affect the overall magnitude of the response. We have used the WST-1 assay to assess human neutrophil dysfunction and to compare anti-inflammatory activity.

Isolation and characterization of two immunochemically distinct alkaline phosphatases from Pseudomonas aeruginosa.

We have isolated two alkaline phosphatases (H-AP and L-AP, for high and low molecular mass, respectively) from Pseudomonas aeruginosa PA01. These two enzymes were found to differ in mobility on sodium dodecyl sulphate polyacrylamide gels (H-AP, M(r) = 51,000 and L-AP, M(r) = 39,500), amino-terminal amino acid sequence and did not cross-react. Both enzymes were active as phosphomonoesterases while only L-AP demonstrated any phosphodiesterase activity. Both enzymes were purified from P. aeruginosa grown in phosphate limiting conditions using the same protocol and were identified in both periplasmic and extracellular locations. A low level of H-AP was produced constitutively whereas L-AP was produced only after induction by reduced phosphate concentration in the growth medium. An L-AP-like enzyme has been previously described, however, this is the first report of a second P. aeruginosa alkaline phosphatase.

Overview of legislation and tobacco control in Singapore.

Legislative measures against smoking in Singapore began in the early 1970s, and can be said to have been the start of a comprehensive smoking control programme. With the launch of the National Smoking Control Programme (NSCP) in 1986, a National Smoking Control Coordinating Committee was set up to look into legislation and fiscal measures. To further increase the dimension and impact of the programme, a Civic Committee on Smoking Control was formed in 1996. This committee also looks into and recommends legislative measures. The NSCP is an ongoing programme that aims to reduce smoking rates through a combination of strategies, including education, establishment of no-smoking areas and increasing taxation and legislative measures. Existing legislation is regularly and systematically reviewed and revised, and new laws are recommended to strengthen our smoking control efforts. Concurrently, penalties and ways to improve enforcement of the legislation are also updated. The legislative measures that have been implemented in Singapore over the years include prohibition of tobacco advertising and promotion, restrictions on the sale of tobacco products, licensing of sales outlets, use of health warnings on cigarette packets, controlling and labelling of tar and nicotine contents, restriction of smoking in public places and prohibition of smoking in public by the under-eighteens. Several factors have helped make legislative measures work in Singapore. These include political will and support, starting legislation early, comprehensive legislative measures, enforcement measures and continuous review. To sustain these efforts, Singapore needs to continue to stay abreast of world-wide measures on smoking control.

The glucose challenge test for screening gestational diabetes in pregnant women with no risk factors.

AIM OF STUDY: To evaluate the 50 g glucose challenge test as a screening tool for gestational diabetes in pregnant women with no risk factors, to determine the prevalence of gestational diabetes in this population and to determine the perinatal outcomes of pregnancy according to the glucose challenge test. METHODOLOGY: A descriptive prospective study. A total of 146 patients with no risk factors who booked a particular obstetrician and delivered between May 1996 and April 1997 were recruited. Pregnancy outcomes were assessed by the gestation and mode of delivery, neonatal outcomes included birth weights, apgar scores and other neonatal complications. RESULTS: The detected incidence of gestational diabetes was 8.2%. With the threshold plasma glucose level at 7.1 mmol/l, 53 women or 36% needed to undergo the 75 g oral glucose tolerance test and 12 women were found to have gestational diabetes. The diagnostic yield was 22.6%. With 7.8 mmol/l as the threshold value, 28 women or 20% needed the oral glucose tolerance test and eight women with gestational diabetes were detected. The diagnostic yield was 28.6%. Perinatal outcome for these diabetic women who were well-controlled during pregnancy was similar to the rest of the women with normal glucose challenge test. CONCLUSIONS: The 50 g glucose challenge test is a useful screening test for diabetes in Singaporean women with no risk factors. A threshold value at 7.8 mmol/l with a smaller number of women requiring the 75 g oral glucose challenge test may be more acceptable.

Perioperative management of a patient with congenital myasthenia gravis for elective caesarean section.

Congenital disorders of neuromuscular transmission are commonly referred to as congenital myasthenia gravis because of their clinical similarity to the immune-mediated disease. Differentiation between the immune-mediated and congenital forms of the disease is important, because therapy established for the former may not be appropriate for patients with the latter presentation. The course of this rare neuromuscular disorder during pregnancy and its influence on anaesthesia remain largely unknown. We report on the case of a 32-year-old parturient suffering from congenital myasthenia gravis scheduled for elective caesarean section. The perioperative management of this patient who underwent the operation under spinal anaesthesia was reviewed. The effects of anaesthetic agents and techniques on the course of congenital myasthenic patients may need further review in the light of latest findings in the electrophysiology, genetic and therapeutic studies of this syndrome.

Patient education in the management of diabetes mellitus.

AIM: A patient education programme in the management of diabetes mellitus (DM) was piloted in a government polyclinic. This study aimed to evaluate the effectiveness of the education programme in improving knowledge of DM and skills in self-care in order to achieve long term control of DM. METHOD: The study was carried out on an intervention group of 183 diabetic patients who completed the education programme and a control group of 95 diabetic patients who attended the clinic during the period of the study. The patients were assessed on their knowledge of diabetes and their practice for good control of the disease (dietary practice, compliance, home monitoring) through a questionnaire. Long term control was assessed by their glycosylated haemoglobin levels. The education programme comprised individual counselling using a diabetes education guide, talks, videoshows and food displays. RESULTS: The intervention group showed a significant and greater improvement in the knowledge of the disease and self-care and in the dietary practice (taking more unpolished rice/high fibre food, reducing calories intake and cutting down oily/fatty food) when compared to the control group. Compliance with medication and the mean HbA1c levels were also improved in the intervention group. CONCLUSION: In this study the educational intervention was observed to have improved the diabetic patients' knowledge of the disease and self-care and the long term control of the disease. Patient education is thus an important component in the management of diabetes mellitus.