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Biomedical subjects

S F Wong

Publications and source records attributed to S F Wong.

At least 37 records · Page 2Linked to original sources
PubMed2002

Risk factors for preterm delivery in women with placenta praevia and antepartum haemorrhage: retrospective study.

OBJECTIVE: To identify risk factors for preterm delivery in women with placenta praevia and antepartum haemorrhage. DESIGN: Retrospective study. SETTING: Regional obstetric unit, Hong Kong. SUBJECTS AND METHODS: Women delivered at Princess Margaret Hospital between 1 January 1990 and 31 December 1997. Possible risk factors for preterm delivery among women with placenta praevia and antepartum haemorrhage including onset, pattern, and severity of vaginal bleeding; presence of uterine contractions on admission; and type of placenta were assessed. RESULTS: Three risk factors for preterm delivery were identified from univariate analysis. These included second trimester vaginal bleeding (odds ratio=4.19; 95% confidence interval, 1.29-13.66), the presence of uterine contractions on admission (odds ratio=4.00; 95% confidence interval, 1.57-10.19), and a haemoglobin decrease of more than 20 g/L (odds ratio=3.00; 95% confidence interval, 1.00-9.04). Using the logistic regression model, second trimester vaginal bleeding and the presence of uterine contractions were found to be independent risk factors for delivery before 36 weeks. CONCLUSION: Preterm delivery is increased in women with placenta praevia and antepartum haemorrhage who have second trimester vaginal bleeding or the presence of uterine contractions. This high-risk group may benefit from close in-patient monitoring and more aggressive management.

Adult↗
PubMed2001

The effect of fetal gender on nuchal translucency at 10-14 weeks of gestation.

Recent data have suggested that fetal nuchal translucency (NT) is affected by fetal gender. We investigated the size of this effect in 12 189 unselected pregnancies with known normal outcomes that had undergone NT measurements between 10 and 14 weeks of gestation. NT increased with gestation and was converted to multiples of the median (MoM) for the gestational day. The median NT MoM (95% CI) for female fetuses was 0.98 (0.97-0.99). This was significantly lower than that of the male fetuses (1.03; range 1.02-1.04) (p<0.0005; Wilcoxon rank-sum test). The gender difference was not observed at 10 weeks but was observed from 11 weeks onwards. There is no obvious explanation for the above findings.

Adult↗
PubMed2001

Sex selection in practice among Hong Kong Chinese.

The aim of this study is to identify factor(s) influencing imbalance in the sex distribution of children (more children of the same sex) of the multiparous women attending an antenatal clinic in Hong Kong. A retrospective study was carried out to compare the expected and observed sex ratios of babies born to women with one previous live birth and women with two. All singleton pregnant women of parities 1 and 2 delivering after 22 weeks of gestation, between 1 July 1996 and 30 June 1998, were included. A total of 2604 women of parity 1 and 752 women of parity 2 were included. The sexes of the children of parity 1 women and the sex distribution of their newborns were consistent with the predicted value. The parity 2 women were more likely to have third children if their previous children were of the same sex (p-value < 0.001). This implies that the parity 2 women attending our antenatal clinic had third pregnancies because of social, economical or environmental reasons. Our parity 2 women with two daughters were more likely to have sons (p < 0.05). Thus, biological or parental factors were unlikely to be important in influencing the sex of the newborn. This suggested that sex selection or sex-selective abortion might be practiced among Hong Kong Chinese women.

China↗
PubMed2001

Effect of transforming growth factor-beta1, insulin-like growth factor-I and insulin-like growth factor-II on cell growth and oestrogen metabolism in human breast cancer cell lines.

Oestrogens play an important role in the development of breast cancer. Oestrone sulphate (E1S) acts as a huge reservoir of oestrogens in the breast and is converted to oestrone (E1) by oestrone sulphatase (E1STS). E1 is then reversibly converted to the potent oestrogen, oestradiol (E2) by oestradiol-17beta hydroxysteroid dehydrogenase (E2DH). The aim of this study was to assess the effects of transforming growth factor-beta1 (TGFbeta1), insulin-like growth factor-I (IGF-I) and insulin-like growth factor-II (IGF-II) on cell growth, E1STS and E2DH activities in the MCF-7 and MDA-MB-231 human breast cancer cell lines. TGFbeta1, IGF-I and IGF-II alone or in combination inhibited cell growth of both cell lines but no additive or synergistic effects were observed. The treatments significantly stimulated E1STS activity in the MCF-7 cell line, except for TGFbeta1 alone and TGFbeta1 and IGF-I in combination, where no effects were seen. Only TGFbeta1 and IGF-II acted synergistically to stimulate E1STS activity in the MCF-7 cells. There was no significant effect on E1STS activity in the MDA-MB-231 cells with any of the treatments. In the MCF-7 cells, TGFbeta1 and IGF-I, IGF-I and IGF-II, and TGFbeta1, IGF-I and IGF-II acted synergistically to stimulate the reductive E2DH activity, while only TGFbeta1, IGF-I and IGF-II synergistically stimulated the oxidative E2DH activity. There were no additive or synergistic effects on both oxidative and reductive E2DH activities in the MDA-MB-231 cells. In conclusion, TGFbeta1, IGF-I and IGF-II may have effects on oestrogen metabolism, especially in the MCF-7 cell line where they stimulated the conversion of E1S to E1 and E1 to E2 and, thus, may have roles to play in the development of breast cancer.

Breast Neoplasms↗
PubMed2001

Findings in women with postmenopausal bleeding investigated with hysteroscopy.

Most reports on histopathological findings of postmenopausal bleeding were published before hysteroscopy was widely used. Recent studies have shown that hysteroscopic examination is better than dilatation and curettage alone in detecting intrauterine pathology. The aim of this study is to assess histopathological findings of patients presented with postmenopausal bleeding after incorporation of hysteroscopic examination. Between 1 January 1996 and 31 December 1996, a total of 199 consecutive patients presenting with postmenopausal bleeding to a regional hospital were reviewed. Patients were investigated with cervical biopsy, endometrial aspiration or hysteroscopy and curettage. Excluding patients who had hysterectomy and cervical cancer, 97% of the patients had hysteroscopic examination. The majority of patients with postmenopausal bleeding had atrophic vaginitis and/or atrophic endometrium (58.8%). Other common diagnoses were endometrial polyp (9.4%), endometrial carcinoma (9.4%) and carcinoma of the cervix (6%). Other diagnoses included submucous fibroid, endometrial hyperplasia, pyometra, ovarian cancer and urethral caruncle. Pathologies found were similar to early reports, except that incidences of submucous fibroids and endometrial polyps were higher (13.4%). We concluded that all patients with postmenopausal bleeding should be investigated thoroughly as 22% have significant pathology. Hysteroscopy is the preferred investigation because of high incidences of endometrial polyps and submucous fibroids.

Journal Article↗
PubMed2001

Sonographic estimation of fetal weight in macrosomic fetuses: diabetic versus non-diabetic pregnancies.

The objective of this study is to compare the accuracy of sonographic estimation of fetal weight of macrosomic babies in diabetic vs non-diabetic pregnancies. All babies weighing 4,000 g or more at birth, and who had ultrasound scans performed within one week of delivery were included in this retrospective study Pregnancies with diabetes mellitus were compared to those without diabetes mellitus. The mean simple error (actual birthweight--estimated fetal weight); mean standardised absolute error (absolute value of simple error (g)/actual birthweight (kg)); and the percentage of estimated birthweight falling within 15% of the actual birthweight between the two groups were compared. There were 9,516 deliveries during the study period. Of this total 1,211 (12.7%) babies weighed 4,000 g or more. A total of 56 non-diabetic pregnancies and 19 diabetic pregnancies were compared. The average sonographic estimation of fetal weight in diabetic pregnancies was 8% less than the actual birthweight, compared to 0.2% in the non-diabetic group (p < 0.01). The estimated fetal weight was within 15% of the birthweight in 74% of the diabetic pregnancies, compared to 93% of the non-diabetic pregnancies (p < 0.05). In the diabetic group, 26.3 % of the birthweights were underestimated by more than 15 %, compared to 5.4% in the non-diabetic group (p < 0.05). In conclusion, the prediction accuracy of fetal weight estimation using standard formulae in macrosomic fetuses is significantly worse in diabetic pregnancies compared to non-diabetic pregnancies. When sonographic fetal weight estimation is used to influence the mode of delivery for diabetic women, a more conservative cut-off needs to be considered.

Abdomen↗
PubMed2001

Oral bexarotene in the treatment of cutaneous T-cell lymphoma.

OBJECTIVE: To review the preclinical and clinical information related to oral bexarotene approved by the Food and Drug Administration for the treatment of cutaneous manifestations of cutaneous T-cell lymphoma (CTCL) in patients who are refractory to at least one prior systemic therapy. DATA SOURCES: Literature accessed through MEDLINE (from 1990 to July 2000) and provided by the manufacturer. Key search terms included bexarotene, Targretin, LGD1069, and cutaneous T-cell lymphoma. DATA SYNTHESIS: The management of CTCL remains controversial due to its rarity in the US and its heterogeneity. An evaluation focusing on the pharmacology of bexarotene and its role in the management of the different stages of CTCL was conducted. CONCLUSIONS: Bexarotene has demonstrated activity in the treatment of CTCL. The oral route of administration and the adverse effect profile of bexarotene appear to make this drug a favorable option for the treatment of CTCL. Compared with other systemic therapies. Phase III randomized studies are needed to determine the clinical benefits of bexarotene as monotherapy or combination therapy in the treatment of CTCL.

Administration, Oral↗
PubMed2001

The role of TGFbeta in human cancers.

Transforming growth factor beta (TGFbeta) is secreted as a large latent precursor from both normal and transformed cells which needs to be activated for biological activity. The active TGFbeta binds either directly to TbetaR-II or indirectly by binding to beta-glycan which then presents the TGFbeta to TbetaR-II. Formation of the TGFbeta-TbetaR-II complex rapidly leads to phosphorylation of TbetaR-I. TbetaR-I, in turn, phosphorylates receptor-specific Smads and induces their translocation into the nucleus. TGFbeta is able to act as a growth stimulator or inhibitor and elicits a broad spectrum of biological effects on various cell types. However, these cells may lose their sensitivity and responsiveness to TGFbeta. Down-regulation or loss of functional receptors, aberrant signal transduction pathways due to Smad mutations, loss of the cell's ability to activate latent TGFbeta, loss of the peptide itself or functional genes that control the transcription and translation of TGFbeta may contribute to development of cancer.

DNA-Binding Proteins↗
PubMed2001

Pyometra. What is its clinical significance?

OBJECTIVE: To evaluate the clinical outcomes of pyometra. STUDY DESIGN: Retrospective study conducted between 1993 and 1999 in two regional hospitals. RESULTS: Pyometra represented 0.038% of gynecologic admissions. Of the 27 women with pyometra, 6 (22.2%) cases were associated with malignancy, 1 (3.7%) was associated with genital tract abnormality, and 20 (74.1%) were idiopathic. Patients with idiopathic pyometra tended to be older and had a higher incidence of concurrent medical conditions. Five (18.5%) women experienced spontaneous perforation of pyometra. A preoperative diagnosis was correctly made in 17 of 22 (77.3%) patients without spontaneous perforation. Most women were treated with dilatation of the cervix and drainage. Nine women (33.3%) had persistent or recurrent pyometra; three of them were asymptomatic. CONCLUSION: Pyometra is an uncommon condition, but the incidence of associated malignancy is considerable, and the risk of spontaneous perforation is higher than previously thought. Dilatation and drainage is the treatment of choice, and regular monitoring after initial treatment is warranted to detect persistent and recurrent disease.

Adult↗
PubMed2000

Acceptability of serum screening as an alternative to cytogenetic diagnosis of down syndrome among women 35 years or older in Hong Kong.

The addition of second trimester serum markers to maternal age increases the efficacy of screening for Down syndrome by maternal age alone. Among women aged 35 years or older, serum screening makes a large proportion of amniocentesis unnecessary. However, there are ethical and medicolegal concerns about serum screening in 'old' women, largely because some of the pregnancies affected by Down syndrome and other chromosomal abnormalities may not be detected. We investigated the acceptability of serum screening in women aged 35 years or older when it was offered as an alternative to prenatal cytogenetic diagnosis after detailed counselling. Women referred for prenatal diagnosis of Down syndrome because of advanced maternal age were given the options of cytogenetic diagnosis by chorionic villus sampling (CVS) or amniocentesis. As an alternative, they could choose to undergo second trimester serum human chorionic gonadotrophin (hCG) and alpha-fetoprotein (AFP) screening first before deciding on whether to undergo amniocentesis. Between January 1997 and October 1999, 3419 subjects were recruited. 1807 women (52. 9%) chose to undergo serum screening, 1516 women (44.3%) chose to have amniocentesis and 96 women chose to have CVS (2.8%). The proportion of women who chose serum screening rose steadily from 38. 8% in the year of 1997 to 63.4% in 1999. Significantly fewer Chinese women chose serum screening than non-Chinese. The decision as to whether to undergo an invasive diagnostic procedure or to be content with the relatively safer but less accurate screening test varies, being affected by the women's background and culture.

Adult↗
PubMed2000

Succinylcholine-associated postoperative myalgia.

The subject of postoperative myalgia associated with the use of succinylcholine is reviewed. We discuss the mechanisms of succinylcholine-induced myalgia and the techniques available to prevent and treat the myalgia. In situations where patients are at risk of developing myalgia and succinylcholine is the neuromuscular blocker of choice, the use of a combination of techniques may prove to be a useful strategy.

Fasciculation↗
PubMed2000

Women with placenta praevia and antepartum haemorrhage have a worse outcome than those who do not bleed before delivery.

We set out to assess the maternal and neonatal outcomes of women with placenta praevia and antepartum haemorrhage (APH) between 1991 and 1997, compared with woman with a diagnosed placenta praevia who did not bleed. The demographic data, maternal and perinatal outcomes of 159 women with antepartum haemorrhage were compared with 93 women without antepartum haemorrhage in a retrospective study. Women with antepartum haemorrhage had the diagnosis of placenta praevia confirmed at an earlier gestation. More women with antepartum haemorrhage received antenatal steroids and tocolytic agents, and had emergency caesarean sections. The majority of women with bleeding had an emergency caesarean section for antepartum haemorrhage and more delivered early because of fetal distress. There were more preterm deliveries in women with antepartum haemorrhage. The mean birth weight was 2.69 kg in the women with antepartum haemorrhage and 3.06 kg in those without. More infants in the bleeding group had a low Apgar score at the first minute, respiratory distress syndrome, and admission to special baby care and neonatal intensive care unit. It is concluded that there is an increased risk of premature delivery in women with antepartum haemorrhage and placenta praevia. Aggressive management, tocolysis and cervical cerclage should be explored further to improve the perinatal outcome. Women without antepartum haemorrhage can be managed on an outpatient basis.

Journal Article↗
PubMed2000

Predictive factors of post-discharge mortality in the hospitalised elderly.

AIM: To study the death rate of noninstitutionalised elderly after discharge from hospital, describe the causes of death and identify predictive factors of mortality. METHODS: Vital status and cause of death of patients was ascertained by linkage to the death registry I year post discharge. Age, sex, race, marital status, housing and class of ward (to reflect socioeconomic status), presence of carer, Elderly Cognitive Assessment Questionnaire (ECAQ) score, Barthel score, presence of depression, number of chronic illnesses and length of stay in the hospital were studied as potential predictive factors for mortality using Cox proportional hazard regression models. RESULTS: Death occurred in 38 out of 113 patients. The commonest causes of death were malignancy (18%) and cerebrovascular disease (18%). Barthel score and length of stay were independent significant predictive factors of mortality. Elderly with low ECAQ score, with carers and from C class wards also had higher mortality although these results were not statistically significant. CONCLUSION: Post-discharge mortality is high in the elderly. We recommend that further studies be done to determine if amelioration of these predictive factors would lead to decreased mortality or improvement of quality of life.

Aged↗
PubMed1999

Small cell carcinoma of the cervix complicated by pregnancy.

We report the results of treatment in a 26-year old patient with stage IB2 small cell carcinoma of the cervix complicated by pregnancy. A pathological complete remission was achieved following sandwich chemotherapy and radiotherapy. The patient remains in clinical remission 14 months after presentation.

Adult↗
PubMed1999

Perceived need for community geriatric services: a survey at a regional hospital in Singapore in an inpatient setting.

Our primary aim was to study the need for community services as perceived by the elderly and their relatives. A secondary objective was to determine the predictive factors of need for these services. This is a survey of 115 consecutive non-institutionalised patients admitted to a hospital geriatric department and their relatives. Twenty-seven elderly patients without cognitive impairment and 115 relatives were interviewed as to their need for community services after discharge. Services most needed by patients were: 24-hour medical helpline (33%), emergency alarm system (19%), social helpline (14%) and day care centre (13%). Services most needed by relatives were: 24-hour medical helpline (70%), emergency alarm system (40%), home visits by doctors (40%), respite care (35%), day care centre (35%) and transport service (33%). There were low levels of need for home help service, meal delivery service and the befriender service. Important predictive factors of need were: low ECAQ (Elderly Cognitive Assessment Questionnaire) score, low Barthel score, and absence of a carer. The development of community geriatric services in Singapore should be guided by the perceived needs of the elderly and their relatives/care-givers. This study is limited by its hospital-based perspective and small numbers. We recommend that further community-based studies be carried out to complement our study and extend our findings.

Activities of Daily Living↗
PubMed1998

Abrogation of autoimmune diabetes in nonobese diabetic mice and protection against effector lymphocytes by transgenic paracrine TGF-beta1.

Paracrine effect of transforming growth factor-beta1 (TGF-beta1) on autoimmune insulitis and diabetes was studied by transgenic production of the active form of porcine TGF-beta1 (pTGF-beta1) in pancreatic islet (islet) alpha cells in nonobese diabetic (NOD) mice under the control of rat glucagon promoter (RGP) (NOD-RGP-TGF-beta1). None of 27 NOD-RGP-TGF- beta1 mice developed diabetes by 45 wk of age, in contrast to 40 and 71% in male and female nontransgenic mice, respectively. None of the NOD-RGP-TGF-beta1 mice developed diabetes after cyclophosphamide (CY) administration. Adoptive transfer of splenocytes of NOD-RGP-TGF-beta1 mice to neonatal NOD mice did not transfer diabetes after CY administration. Adoptive transfer of three types of diabetogenic lymphocytes to NOD-RGP-TGF-beta1 and nontransgenic mice after CY administration led to the lower incidence of diabetes in NOD-RGP-TGF-beta1 mice versus that in nontransgenic mice: 29 vs. 77% for diabetogenic splenocytes, 25 vs. 75% for islet beta cell-specific Th1 clone cells, and 0 vs. 50% for islet beta cell-specific CD8(+) clone cells, respectively. Based on these, it is concluded that autoimmune diabetes in NOD mice is not a systemic disease and it can be completely prevented by the paracrine TGF-beta1 in the islet compartment through protection against CD4(+) and CD8(+) effector lymphocytes.

Adoptive Transfer↗