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T K Chung

Publications and source records attributed to T K Chung.

At least 37 records · Page 2Linked to original sources
PubMed2000

Analysis of mid-trimester corticotrophin-releasing hormone and alpha-fetoprotein concentrations for predicting pre-eclampsia.

The aims of this study were firstly to examine if corticotrophin-releasing hormone (CRH) concentrations in maternal plasma were significantly elevated in Chinese pregnancies complicated by pre-eclampsia, secondly to assess if this elevation could be detected in the mid-trimester before onset of clinical signs of the disease, and thirdly to evaluate the performance of using maternal CRH and/or alpha-fetoprotein (AFP) concentrations in the mid-trimester for prediction of pre-eclampsia. The first part of this study was tested in a cohort of 39 subjects. The CRH concentrations were significantly elevated in pregnant women complicated by pre-eclampsia. The second and third parts of the study involved a different cohort of 1021 subjects. Both CRH and AFP concentrations in the mid-trimester were significantly elevated in those who subsequently developed pre-eclampsia. However, when used for prediction of pre-eclampsia, neither the CRH nor AFP concentrations alone in the mid-trimester had strong predictive value. Although the combination of both tests improved the detection rate compared to the use of CRH alone, the small increase in the likelihood ratio from 1.9 to 2.6 did not suggest that the combination would be of great clinical value.

Adult↗
PubMed2000

Overexpression of p53 and HER-2/neu and c-myc in primary fallopian tube carcinoma.

Primary fallopian tube carcinoma is a rare form of female cancer and the genetic basis of its carcinogenesis remains unclear. Eighteen cases of primary fallopian tube adenocarcinoma were studied. Immunohistochemical staining for p53, HER-2/neu and c-myc genes were performed. Overexpression of p53 was detected in 12 cases (67%), HER-2/neu in 16 cases (89%), and c-myc in 11 cases (61%). The potential relevance of overexpression of the three genes with clinicopathological features was examined, but no significant correlation was found. The high incidence of p53, HER-2/neu and c-myc overexpression in fallopian tube adenocarcinoma suggests these genes may play a role in its tumorigenesis.

Adenocarcinoma↗
PubMed2000

p53 polymorphism and human papillomavirus infection in Hong Kong women with cervical cancer.

In this study we investigated the involvement of p53 polymorphism at codon 72, the infection and typing of human papillomavirus (HPV) and the correlation of p53 polymorphism with HPV type and other clinicopathologic characteristics in 72 Hong Kong women with cervical cancer. We developed a simple and nonradioactive method for determining polymorphism at codon 72 of the p53 gene. The homozygous p53 arginine allele (Arg/Arg) was detected in 22 (31%), the homozygous p53 proline allele (Pro/Pro) in 14 (19%) and the heterozygous allele (Arg/Pro) in 36 (50%) cases, respectively. Using the consensus primers MY11 and MY09, HPV infection was detected in 55 of 72 (76%) cases. The prevalent types were HPV-16 (55%), HPV-18 (16%) and HPV-58 (9%). The number of HPV-positive cases with Arg/Arg, Pro/Pro and Arg/Pro were 17 (31%), 12 (22%) and 26 (47%), respectively. The p53 polymorphism at codon 72 was not significantly correlated with any of the HPV types (p > 0.05). No striking overrepresentation of homozygous arginine-72 p53 was observed in HPV-associated cervical cancer. The results in this study did not show that any p53 polymorphic form has a prognostic significance for cervical cancer.

Codon↗
PubMed2000

Identifying women at risk of postnatal depression: prospective longitudinal study.

OBJECTIVE: To identify psychosocial risk factors for postnatal depression among Hong Kong Chinese women. DESIGN: Prospective longitudinal study involving self-report questionnaires and face-to-face interviews. SETTING: University teaching hospital, Hong Kong. PARTICIPANTS: Two hundred and twenty consecutive Chinese women who were admitted to the postnatal ward of the Department of Obstetrics and Gynaecology from 6 November 1996 to 18 January 1997. MAIN OUTCOME MEASURES: Psychiatric diagnoses were established using the clinician-administered Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders. Psychosocial risk factors were ascertained by conducting face-to-face interviews and using psychometric rating scales. RESULTS: Of the 330 women who delivered during the study period, 220 (66.7%) agreed to participate in the study. The 220 participants had a mean age of 29 years (range, 16-42 years). Postnatal depression was associated with depression during pregnancy, elevated depression score at delivery, and prolonged postnatal 'blues'. Other correlates of postnatal depression were temporary housing accommodation, financial difficulties, two or more induced abortions, past psychiatric disorders (including depression), and an elevated neuroticism score. Postnatal depression was more likely if the spouse was disappointed with the gender of the newborn. CONCLUSION: Some risk factors are similar to those found in the West, whereas others (spouse disappointment and history of abortion) may be unique to the local population. To help identify women who are at particularly high risk of developing postnatal depression, obstetricians and midwives in Hong Kong should consider codifying the identified risk factors into a check-list.

Adolescent↗
PubMed1999

Allelic loss on chromosome 1 is associated with tumor progression of cervical carcinoma.

BACKGROUND: Alterations in chromosome 1 are common in human malignancies. The frequency of loss of heterozygosity (LOH) on chromosome 1 in cervical carcinoma and its clinical significance are not clearly understood. METHODS: LOH on chromosome 1 was studied in 100 cervical carcinomas by the polymerase chain reaction (PCR) using 29 highly polymorphic microsatellite markers spaced approximately 10 centimorgans apart. Loci with high frequencies of LOH were identified and the findings were correlated with clinicopathologic characteristics. RESULTS: LOH on chromosome 1 at 1 or more loci was detected in 93% of tumors. The frequencies of LOH at locus D1S2829 (1p31), D1S2663 (1p36.3), and D1S2725 (1q25) exceeded 30%, and 12 other loci exhibited frequencies of LOH of 20-30%. Advanced stage tumors had a significantly higher percentage of informative microsatellite markers with LOH than early stage tumors. Of the 29 microsatellite markers studied, 4 loci had a significantly higher frequency of LOH in Stage III and IV tumors than in earlier stage tumors. CONCLUSIONS: Frequent aberrations on chromosome 1 in cervical carcinoma suggest that inactivation of tumor suppressor genes is important in cervical tumorigenesis. Higher frequencies of LOH in Stage III and IV tumors suggest that chromosome 1 changes are late events in cervical carcinoma. The findings of this study are consistent with earlier reports that suggest that tumor suppressor genes are present at 1p36.3 and 1p31. To the authors' knowledge, the high frequency of LOH mapped to 1q25 has not been reported previously. Its significance awaits further clarification.

Adenocarcinoma↗
PubMed1999

Methylation of p16INK4A in primary gynecologic malignancy.

The p16INK4A gene mapped on band p21 of chromosome 9 can be inactivated via multiple mechanisms including homozygous deletion, point mutation and promoter hypermethylation in various human tumors. A polymerase chain reaction (PCR) based analysis was performed to examine methylation of the p16INK4A gene promoter in 196 primary gynecologic malignancies including 98 cervical, 49 endometrial and 49 ovarian carcinomas. Methylation of p16INK4A was detected in 31% of cervical, 20% of endometrial, and 4% of ovarian carcinomas, respectively. The incidence of p16INK4A methylation in patients with cervical and endometrial carcinomas at advanced stages (stages III-IV) was statistically higher than those at early stages (stages I-II). There were also significant differences in the incidence of p16INK4A methylation in both cancers between the patients who had died of their disease or were alive with evidence of disease, and those without evidence of disease. The results indicate that methylation of the p16INK4A gene is present in a proportion of primary gynecologic malignancies and this alteration may be associated with poor outcome in cervical and endometrial carcinomas.

Adult↗
PubMed1999

Spontaneous abortion: a randomized, controlled trial comparing surgical evacuation with conservative management using misoprostol.

OBJECTIVE: To compare the efficacy of surgical evacuation of the uterus with medical evacuation using misoprostol in cases of spontaneous abortion. DESIGN: A prospective, randomized, controlled trial. SETTING: A university teaching hospital. PATIENT(S): Six hundred thirty-five women who aborted spontaneously and who consented to pretreatment randomization. INTERVENTION(S): Routine surgical evacuation or medical evacuation of the uterus using misoprostol. MAIN OUTCOME MEASURE(S): Immediate, short-term (2-3 weeks), and medium-term (6 months) medical complications. RESULT(S): There was a significantly lower incidence of immediate and short-term complications in the group treated with misoprostol compared with the surgically treated group. There were also fewer major complications in the 6 months after treatment in the medically treated group. Approximately 50% of the medically treated group subsequently required surgical evacuation, and these subjects required significantly more analgesia. CONCLUSION(S): Treatment with misoprostol can reduce the demand for surgical evacuation in cases of spontaneous abortion, and its use is associated with fewer medical complications.

Abortifacient Agents, Nonsteroidal↗
PubMed1999

Abducens nerve palsy complicating pregnancy: a case report.

We report a case presented at 38 weeks gestation with abducens nerve palsy. No specific pathology was found. After reviewing all the previously reported cases, hypertension is found to be a common factor in all cases presenting in late pregnancy. The clinical course is benign and all resolved after delivery.

Abducens Nerve↗
PubMed1999

Patient-related barriers to cancer pain management in a palliative care setting in Hong Kong.

This article reviews a study of pain management and its barriers in Hong Kong. Using an interview technique, several measures were used to understand the level of concern in patients about pain, the patients' hesitancy in reporting pain, use of analgesics, and adequacy of medication for pain. A total of nine barriers were identified, which include "addiction," "tolerance," "side effects," "physician distraction," "good patient," "fear of injection," "time interval," "fatalism," and "disease progression." Thirty-nine interviews were carried out. The interviewees were all cancer patients with pain in a palliative setting in Hong Kong. When the findings in Taiwan and the United States were compared, it was found that the cancer patients in Hong Kong had a higher level of concern toward the patient-related barriers. It was also found that the level of concern was generally higher in the group with hesitancy in reporting pain and using analgesics. Last of all, this project also identified the educational needs of patients and health care workers in Hong Kong.

Adult↗
PubMed1999

Elevated mid-trimester maternal corticotrophin-releasing hormone levels in pregnancies that delivered before 34 weeks.

OBJECTIVE: To test whether maternal corticotrophin-releasing hormone levels are elevated in the mid- trimester for those women who subsequently had spontaneous preterm delivery and to assess the clinical utility of the measurement in the prediction of preterm delivery. DESIGN: A prospective observational study. SETTING: Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Hong Kong. POPULATION: 1047 low risk pregnant women recruited at 15-20 weeks of gestation. METHODS: Venous samples were assayed for levels of corticotrophin-releasing hormone. The investigators responsible for the laboratory assay were blinded to the obstetric outcome. MAIN OUTCOME MEASURES: Incidence of preterm, term and post-term pregnancies. RESULTS: Those who were delivered spontaneously at a preterm gestational age (before 34 weeks) had significantly higher corticotrophin-releasing hormone levels in the mid-trimester, compared with those who were delivered at term or post-term. There was a trend towards lower corticotrophin-releasing hormone levels with more advanced gestational age at delivery. When the measurement of corticotrophin- releasing hormone was used to predict delivery before 34 weeks, the best cut off was 1.9 MoM, which produced a sensitivity of 72.7% and specificity of 78.4%. This translated to a positive predictive value of 3.6%, negative predictive value of 99.6% and relative risk of 9.4 when the background prevalence of spontaneous preterm delivery before 34 weeks was 1.1%. The likelihood ratio was 3.4. CONCLUSIONS: Mid-trimester maternal corticotrophin-releasing hormone levels are elevated in pregnancies destined to deliver preterm before 34 weeks. When used alone in a low risk population, the measurement has a low predictive power for preterm delivery. However, the likelihood ratio of 3 4 implies that in high risk populations the test may be considerably more valuable.

Adult↗
PubMed1999

Threatened abortion: prediction of viability based on signs and symptoms.

OBJECTIVE: To examine the relationship between signs and symptoms associated with threatened abortion and viability of the pregnancy. DESIGN: A prospective observational study SETTING: A university teaching hospital PARTICIPANTS: One thousand consecutive women presenting with a threatened abortion. INTERVENTION: A structured history and an examination were performed as initial clinical assessment. These were followed by transvaginal sonography to determine the status of the pregnancy. MAIN OUTCOMES: The relationship between individual signs and symptoms and the status of the pregnancy was determined. Logistic regression was performed to determine which signs or symptoms were independent predictors of spontaneous abortion. RESULTS: A history of having passed a tissue mass, the presence of products of conception in the vagina and an open cervix were the only sign or symptom associated with a greater than 90% chance that the pregnancy was non-viable. Logistic regression of signs and symptoms at presentation indicated that maternal age greater than 35 years, a history of passing clots vaginally, vaginal bleeding similar to normal menstruation, increasing vaginal bleeding and discrepancy of 4 or more weeks between the uterine size on examination and that which would have been expected by menstrual dates were significant predictors of nonviable pregnancy. A history of vomiting was predictive of a viable pregnancy. CONCLUSION: The clinical assessment of threatened abortion is unreliable in most cases and should be superseded by ready access to sonographic assessment.

Abortion, Threatened↗
PubMed1999

Clinical use of serum c-erbB-2 in patients with ovarian masses.

The c-erbB-2 (Her-2/neu) gene product has a large extracellular domain (ECD) and part of which could be identified in the serum. We measured the serum level of c-erbB-2 ECD in 93 patients, who presented with ovarian masses, with an enzyme immunoassay test and an elevated level was found in 5.5, 16.7 and 38% of patients with benign, borderline and malignant ovarian neoplasms, respectively. This serum marker may reflect the overexpression of c-erbB-2 gene in tumor tissues, which is associated with poor prognosis. However, measurement of c-erbB-2 ECD when used alone or in combination with CA 125 is not useful in differentiating benign from malignant ovarian tumors.

Adult↗
PubMed1999

Prospective study of symptom control in 133 cases of palliative care inpatients in Shatin Hospital.

We report a prospective study assessing the prevalence and severity of physical and nonphysical symptoms, and the benefits from treatment and intervention, in advanced cancer patients presenting to a local palliative care unit in Hong Kong. Patients were assessed by a modified version of the support team assessment schedule (STAS). The study highlighted some symptoms which needed better control, and also reinforced the team morale by demonstrating aspects where there was definite improvement. In general, the STAS was found to be practicable and acceptable by our patients and staff. The most important benefit gained from the study was the successful dissemination of the concept of audit and quality assurance throughout the unit, which is essential for continuous improvement in the future.

Adult↗
PubMed1998

Prospective randomized study of the effect of "add-back" hormone replacement on vascular function during treatment with gonadotropin-releasing hormone agonists.

BACKGROUND: Gonadotropin-releasing hormone agonists (GnRHas) are a group of drugs that with long-term use induce a pseudomenopausal state in which estrogen production is suppressed. They are commonly used in the treatment of sex steroid-dependent conditions. "Add-back" hormone replacement therapy is used to prevent menopause-like symptoms and bone loss during GnRHa treatment, but it is also recognized that hypoestrogenism adversely affects vascular function. The aim of this study was to examine the effect of GnRHa and add-back therapy on vascular reactivity. This model serves as a paradigm for the effect of hormone replacement therapy in postmenopausal women. METHODS AND RESULTS: Measurements of endothelium-dependent and endothelium-independent vascular reactivity were compared in 2 groups of women treated with a GnRHa for 6 months. One group received estrogen/progestogen add-back therapy during the second 3 months of GnRHa treatment. Vascular reactivity was examined by use of ultrasound measurements of changes in brachial artery diameter. Endothelium-dependent changes were assessed during reactive hyperemia, whereas endothelium-independent changes were measured after the administration of glyceryl trinitrate sublingual spray. Treatment with the GnRHa alone had an inhibitory effect on endothelium-dependent relaxation. However, endothelium-dependent relaxation significantly improved in the group receiving add-back therapy (14.6%) compared with the group treated with GnRHa alone (8.6%) (P<0.01). There were no significant endothelium-independent changes in either group. CONCLUSIONS: These results suggest that the administration of add-back therapy has a protective effect on vascular function in GnRHa-induced hypoestrogenism. As a model for the menopause, these results also suggest that the long-term administration of hormone replacement therapy would result in endothelium-dependent arterial relaxation, an observation previously attributed only to the acute administration of estrogen.

Adult↗
PubMed1998

Expression of p16INK4 and retinoblastoma protein Rb in vulvar lesions of Chinese women.

The protein products of the two tumor suppressor genes located on 9p and 13p, p16INK4 and Rb, respectively, play an important role in regulation of the cell cycle and are implicated in tumorigenesis. We examined 49 cases of benign vulvar lesions, vulvar intraepithelial neoplasia (VIN), and squamous cell carcinoma with immunohistochemical staining to determine expression of p16INK4 and Rb. All and 86% of benign lesions expressed Rb and p16INK4, respectively; 40% each of VIN I and VIN III expressed p16INK4 and Rb, respectively; and 37 and 68% of squamous cell carcinomas expressed p16INK4 and Rb, respectively. The combination of the lack of p16INK4 and/or Rb expression increased from benign lesions (14.3%), through VIN I (60%) and VIN III (60%), to invasive squamous cell carcinoma (72%), thus supporting the postulation that alterations in p16INK4 or Rb could be significant events in progression of disease. The loss of Rb expression also increased from stage I carcinoma (16.7%) through stage II (26.7%) and III (44.4%), to IV (50%), suggesting that Rb may play an important role in tumor progression. A larger study on VIN lesions and genetic coding is suggested to further investigate the role of p16INK4, Rb, and other factors in tumorigenesis and progression of vulvar cancers.

Carcinoma, Squamous Cell↗
PubMed1998

Ultrasonographic estimation of postpartum postvoid residual bladder volume: a comparison between transabdominal and transvaginal ultrasonography.

Postvoid residual bladder volume (PVRBV) was estimated in 89 patients with postpartum urinary retention using two ultrasonographic volume estimation methods. The PVRBV estimated by transabdominal and transvaginal ultrasonography are compared using the plot of difference against mean and the paired t-test. Neither showed any significant difference between the two methods (paired sample t-test, P > 0.05). The two methods have high correlation coefficient of 0.903 (Spearman's correlation, P < 0.0001). Either ultrasonographic volume estimation method gives reasonable bladder volume assessment in postpartum patients and could be used interchangeably as the clinical situation requires.

Female↗
PubMed1998

Spontaneous abortion: short-term complications following either conservative or surgical management.

Spontaneous abortion is a common gynaecological condition. It is a commonly held belief that medical morbidity associated with this condition is low and that routine treatment should be surgical evacuation of the uterus. This study was performed to study the short-term complications of spontaneous abortion and its management. Transvaginal sonography (TVS) was used to determine whether retained products of conception (POCs) were visible inside the uterus in women presenting with spontaneous abortion. If tissue was present, surgical evacuation of retained products of conception (ERPC) was performed. If the uterus was empty, the patients were managed expectantly. Four hundred and seventy women were treated with ERPC and 297 were managed expectantly. The complication rate was 3.0% in those managed expectantly compared with 5.8% for those treated by ERPC. Subjects with no POCs on TVS can therefore be managed expectantly without increasing the risk of morbidity associated with this condition.

Abortion, Incomplete↗