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Biomedical subjects

T K Chung

Publications and source records attributed to T K Chung.

At least 73 records · Page 4Linked to original sources
PubMed1997

c-fos overexpression is associated with the pathoneogenesis of invasive cervical cancer.

The molecular genetics of human cervical cancer remains to be defined to a significant extent. The current study examined the prevalence and significance of proto-oncogene c-fos overexpression in cervical cancer. Immunohistochemical staining of c-fos oncoprotein was performed in 27 invasive cervical carcinomas and 30 cervical intraepithelial neoplasias (CINs) managed in our department. Eight normal cervical specimens were used as controls. In the patients with invasive cervical cancer, 8 were stage I, 12 were stage II, and 7 had stage III-IV disease. Three of the cancers were well differentiated, 18 were moderately differentiated and 6 were poorly differentiated. Twenty invasive cervical carcinomas (59%) and 3 CIN (10%) showed overexpression of c-fos. The difference is statistically significant (p < 0.001). No statistically significant relationship was found between c-fos overexpression and clinical stage, histological grade, or survival in invasive cervical cancer. In this population, c-fos overexpression appears to be common in invasive cervical cancer and correlated with the ability of the tumor to become invasive, but is not associated with the progression of cervical cancer.

Female↗
PubMed1996

An examination of the effect of combined cyclical hormone replacement therapy on lipoprotein(a) and other lipoproteins.

Lipoprotein(a) (Lp(a)) is an independent marker of cardiovascular disease which is relatively unresponsive to treatment with most of the commonly prescribed lipid lowering drugs. Concentrations of Lp(a) increase after the menopause, and the primary aim of this study was to determine whether combined hormone replacement therapy was effective in lowering levels of Lp(a) in postmenopausal women. An open longitudinal study was conducted among 42 women who had undergone a spontaneous menopause and were attending the outpatient clinic of the Prince of Wales Hospital, Hong Kong. All subjects were treated with 2 mg oral estradiol daily and 5 mg medroxyprogesterone acetate for 12 days each calendar month. Fasting blood samples for lipoprotein measurement were taken before the commencement of treatment and at 6 and 12 months. Lp(a) levels showed a skewed distribution with a median value before treatment of 9.45 mg/dl (range 1.47-95.62 mg/dl). After 6 months, there was a reduction to 7.70 mg/dl (1.12-72.59 mg/dl) (P < 0.01), and after 12 months the median concentration was 7.14 mg/dl (0.63-69.23 mg/dl) (P < 0.001 0-12 months). There were also significant reductions in the concentrations of apo B from 116.13 to 111.62 mg/dl and LDL-C from 3.02 to 2.74 mmol/l (P < 0.05), plus a lowering of TC of borderline significance. Apo A-I increased from 162.56 to 173.35 mg/dl (P < 0.01), but there were no significant changes in HDL-C or the HDL-C subfractions. TC, LDL-C, apo B and TG concentrations were higher and HDL-C and HDL2-C concentrations were lower when blood was sampled during combined treatment with estrogen and progesterone than when estrogen was being taken alone. Levels of Lp(a) were also lower during the estrogen only phase of treatment, but none of these differences were statistically significant. This study demonstrates that combined cyclical hormone replacement therapy is effective in reducing concentrations of Lp(a). The trend towards a more atherogenic lipid profile during the combined phase of treatment suggests that attention should be given to the timing of blood sampling in future studies of this nature.

Adult↗
PubMed1996

Coincidental renal cell and endometrial carcinoma: a case report.

A case of renal cell carcinoma and coexistent endometrial carcinoma is reported. The renal tumor in the lower pole of left kidney was detected by staging preoperative ultrasound scan and was confirmed to be a multilocular cystic renal cell carcinoma. There were two separate foci of moderately differentiated endometrial cancer in the endometrial cavity. Microscopic tumor deposits were also found in the left ovary and the right obturator pelvic lymph nodes. The multicentric involvement of endometrial cavity is uncommon and even rarer is the association with renal cell carcinoma. To the best of our knowledge, this is the first report of an association between renal cell carcinoma and endometrial cancer. This case demonstrates the importance of complete preoperative investigation before any definitive surgery for cancer. Without the abdominal ultrasound scanning, the asymptomatic renal cell carcinoma would probably have been undetected.

Adenocarcinoma↗
PubMed1996

Sexual behavior in pregnancy among Hong Kong Chinese women.

Sexual behavior during pregnancy was examined in a retrospective study of 150 Hong Kong Chinese women interviewed in the immediate postpartum period. Sexual activity was found to decline abruptly during the first trimester of pregnancy, and continued to decrease in frequency as the pregnancy advanced. The frequency of intercourse was lower both before and during pregnancy than has been reported in similar studies among Western populations. There was no consistent relationship between age, parity, level of education, or employment status and sexual behavior either before or during pregnancy. These results suggest that a relatively conservative attitude toward sexual activity persists within this population.

Adolescent↗
PubMed1996

A randomized, double-blind, placebo-controlled, crossover study on the effect of oral oestradiol on acute menopausal symptoms.

Acute menopausal symptoms occur less frequently in Asian than in Caucasian women. Oestrogen replacement therapy has been shown to be effective in controlling acute symptoms in Caucasians, but the effect of oestrogens is not well documented in Asian women. A randomized, double-blind, placebo-controlled, crossover study of the effect of oral oestradiol on the incidence of acute menopausal symptoms was conducted in 83 Hong Kong Chinese women who had experienced a surgical menopause. Although there was a significant increase in the oestradiol concentration with treatment compared with placebo (P < 0.001), there were no significant differences in the reporting of symptoms between the treatment and placebo groups. There is no obvious explanation for this apparent lack of effect of oestrogen on acute menopausal symptoms in Chinese women. Whilst it may be related to the generally low incidence of symptoms or to a higher dietary intake of phytoestrogens in Chinese women, further studies are necessary to explain these findings.

Administration, Oral↗
PubMed1996

The prevalence of urinary dysfunction in Hong Kong Chinese women.

OBJECTIVE: To determine the prevalence of urinary dysfunction in Hong Kong Chinese women. METHODS: A telephone survey was conducted in the territory of Hong Kong. The subjects were a sample of women between the ages of 10 and 90 years. The main outcome determined was the prevalence of urinary dysfunction. RESULTS: We made 3248 calls, resulting in 819 evaluable responses. Stress incontinence was reported by 21% (174) of respondents, urgency or urge incontinence in 15% (120), urinary frequency in 19% (154), nocturia in 20% (166), bed-wetting in 4% (31), and voiding difficulties in 13% (109). Stress incontinence occurred as the only symptom in 7% (53), the combination of urgency and frequency in 1% (11), and mixed symptoms in 6% (52). Four percent required protective underwear or pads, with 2% wearing protective underwear continuously; 4% were incapacitated by their incontinence. Symptoms of urgency, urge incontinence, frequency, and nocturia increased with increasing age, but voiding difficulties and nocturnal enuresis were unrelated to age. Stress incontinence, urgency, urge incontinence, frequency, nocturia, and voiding difficulties increased with increasing parity to para 4. CONCLUSION: Urinary dysfunction and its patterns appear to be as common and incapacitating in Hong Kong Chinese as they are in other populations.

Adolescent↗
PubMed1996

HER-2/neu gene amplification in cervical cancer in Chinese women of Hong Kong and China.

OBJECTIVE: To determine the amplification of proto-oncogene HER-2/neu in invasive cervical cancer and its relationship with the stage of disease, grade of tumor and prognosis of patients. METHODS: In this retrospective study 70 women with invasive cervical squamous cell carcinoma were included. DNA was extracted from the paraffin-embedded tumor tissue. The amplification of HER-2/neu was studied using a differential polymerase reaction (PCR) technique. Assessment of significance was performed using Peason's Chi-square test and Fisher's exact test. RESULTS: Eleven of the 70 cases (16%) showed an amplification of HER-2/neu but there was no relation between amplification and tumor histologic grading (p = 0.408) or clinical staging (p = 0.180). Follow-up information in 67 patients was available. The incidence of amplification in the patients who were alive with disease was not statistically different from that in the patients who were alive with no evidence of disease (p = 0.315). The incidence of amplification in the patients who died of disease was higher than that in the patients who were still alive, but statistical significance did not reached (p = 0.062). CONCLUSION: The results suggest that HER-2/neu amplification does exist in a subgroup of invasive cervical cancer and may play a role in cervical carcinogenesis. The role as independent prognostic factor has to be evaluated by further prospective studies.

Base Sequence↗
PubMed1996

Ovarian epithelial tumour in gonadal dysgenesis. A case report and literature review.

A patient with gonadal dysgenesis was found to have a mucinous epithelial ovarian tumour on the left side and a streak gonad on the right. The preponderance of mucinous tumours (5 of 8) over other epithelial tumours in these patients is noted but the significance is not fully understood. Two models of pathogenesis (incessant ovulation and hypergonadotrophic hypogonadism) were proposed but neither satisfactorily explains the development of the tumours. Further ultrastructural, chromosomal and molecular biological study of these tumours may help to elucidate the underlying cause and pathogenesis.

Adult↗
PubMed1995

Frequent ras gene mutations in squamous cell cervical cancer.

Eighty samples of cervical invasive squamous cell carcinoma were examined for ras gene mutations using polymerase chain reaction (PCR) followed by restriction enzyme digestion. We found 28 (35%) cervical cancers contained ras mutations at H-ras codon 12, 49 (61%) at K-ras codon 12, and 5 (6%) at K-ras codon 13. There were no significant differences in incidence of the ras gene mutations among different histologic grades or clinical stages of the cancer (P > 0.05). This result suggests that ras mutation may be an important step involved in a substantial number of cervical carcinoma. The interaction of ras with other genes and/or events may also be involved in pathogenesis of this malignancy.

Alleles↗
PubMed1995

The perception of the menopause and the climacteric among women in Hong Kong and southern China.

BACKGROUND: A lack of awareness of the long-term consequences of the menopause may be a major contributing factor to the low demand for hormone replacement therapy in Hong Kong and China. Most Chinese women suffer few acute menopausal symptoms, and it was our hypothesis that they had little knowledge of the risks of developing either osteoporosis or cardiovascular disease as a result of estrogen deficiency. METHODS: A prospective study was conducted among 200 Chinese women of all ages living in Hong Kong or southern China. A structured questionnaire was used to examine their perception of the menopause and the climacteric. RESULTS: While 96% of women from Hong Kong and 73% from southern China could define the menopause, none in either group were aware of the problems of either osteoporosis or cardiovascular disease in post-menopausal women. Only 8% of women from Hong Kong and 4% from southern China knew that hormone replacement therapy could be used to treat postmenopausal women. CONCLUSIONS: The results of this study confirm a relative lack of understanding of the climacteric in both groups of Chinese women. As menopausal symptoms are also infrequent in this population, most women will not have the need to consult a physician and will therefore not have the option of taking hormone replacement therapy to prevent the long-term effects of estrogen deficiency. Considering the sizes of the populations involved, the potential for reducing morbidity and mortality through improved education about the menopause is considerable.

Adult↗
PubMed1995

The effect of percutaneous oestrogen replacement therapy on Lp(a) and other lipoproteins.

OBJECTIVES: To determine the effect of percutaneous oestrogen replacement therapy on lipoprotein (a) and other plasma lipoproteins. METHODS: Open longitudinal prospective study conducted at the hormone replacement clinic of the Prince of Wales Hospital, New Territories, Hong Kong. Thirty women who had undergone a total abdominal hysterectomy and bilateral salpingo-oophorectomy for benign gynaecological conditions were treated with 1.5 mg of percutaneous 17 beta-oestradiol gel applied daily for a period of 12 consecutive months. Measurements of plasma lipoproteins were made before the commencement of treatment and repeated at 6- and 12-month intervals. RESULTS: There was a significant reduction in the concentrations of Lp(a) during the first 6 months of treatment, with median values falling from 7.87 mg dL-1 to 6.16 mg dL-1 (P = 0.004, 0-6 months). During the second 6 months, the median concentration increased to 9.38 mg dL-1, (P = 0.072, 6-12 months), which did not significantly differ from the baseline level (P = 0.545, 0-12 months). Significant reductions in the concentrations of apoprotein A-I (apo A-I), apoprotein B (apo B), high density lipoprotein cholesterol (HDL-C), and HDL3-C were also present after 6 months (P = 0.043, 0.049, 0.028, 0.013, respectively), but there were no differences between the baseline values of these lipoproteins and those at the completion of the study (P = 0.948, 0.244, 0.839, 0.117 respectively). Drug compliance was maintained throughout the study, with similar mean oestradiol concentrations at 6 and 12 months. CONCLUSIONS: The percutaneous administration of 17 beta-oestradiol has variable short term effects on plasma lipoproteins which are not maintained over a longer duration of treatment. By avoiding the 'first pass' effect on the liver, this method of delivery does not appear to produce the sustained changes in lipoproteins seen with oral treatment.

Administration, Cutaneous↗
PubMed1995

Calcium supplementation and bone mineral density in postmenopausal women using estrogen replacement therapy.

Both estrogen and calcium have been shown to be of benefit in reducing the incidence of osteoporosis in postmenopausal women. It has been suggested that estrogen promotes the intestinal absorption of calcium, and this effect may especially benefit postmenopausal women with a low dietary intake of calcium. The purpose of this study was to examine the effect of calcium supplementation on the bone mineral density (BMD) of postmenopausal women using estrogen replacement therapy. BMD measurements were made over 12 months in two groups of postmenopausal women, one having treatment with estrogen alone, and the second having estrogen and 1000 mg of supplemental calcium each day. There was no significant reduction in BMD between the two groups over the 12-month study period. Those in the group having supplemental calcium had a significant increase in BMD at the femoral neck (p = 0.023), but not in other areas of the femur nor in the lumbar spine. The results of this study suggest that the addition of supplemental calcium may improve the bone mass of postmenopausal women using estrogen who have a low dietary calcium intake. This benefit appears to be more pronounced in corticocancellous than in trabecular bone, and may therefore have a greater effect on the femoral neck than the lumbar spine.

Absorptiometry, Photon↗
PubMed1995

Second and early third trimester atrial natriuretic peptide (ANP) levels in pregnancies subsequently complicated by hypertension.

OBJECTIVE: To explore the clinical utility of measuring atrial natriuretic peptide (ANP) in the second and early third trimesters of pregnancy in order to predict pregnancy induced hypertension (PIH). METHODS AND MATERIALS: The study was done in a University Teaching Hospital. A prospective study of 200 women in their first pregnancy was conducted. ANP was measured at 2 gestational windows, 20-26 weeks and 30-34 weeks. This was correlated with pregnancy outcomes, in particular PIH. Student's t-test was used to compare ANP levels between women who developed PIH and those who did not. The receiver operator curve (ROC) was used to determine its clinical utility. RESULTS: ANP levels were lower at 20-26 weeks in women who subsequently developed PIH but there was no significant difference at 30-34 weeks between women who had normotensive pregnancies and those who later developed PIH. The character of the ROC would indicate that it is not useful for prediction. CONCLUSION: ANP levels in the second and early third trimesters has limited clinical utility for the prediction of PIH.

Adult↗
PubMed1995

The prediction of fetal acidosis at birth by computerised analysis of intrapartum cardiotocography.

OBJECTIVE: To assess the capability of a computer software interpretation program, using intrapartum fetal heart rate and intrauterine pressure as recorded in a cardiotocogram to predict fetal acidosis at birth. DESIGN AND SUBJECTS: A retrospective analysis of digitised fetal heart rate and uterine activity values obtained from 73 high risk women in labour. SETTING: Two university teaching hospitals. METHODS: A computer software program was constructed to analyse the digitised data and predict acidosis. The results of the analysis were compared with actual umbilical arterial blood pH and base excess at delivery. RESULTS: The software cardiotocogram interpreter was able to predict a pH of less than 7.15 with an accuracy of 77%, a sensitivity of 88% and specificity of 75% in this set of data. It was able to predict a base excess of less than -8 mmol/l with an accuracy of 81%, a sensitivity of 76% and specificity of 82%. CONCLUSIONS: A computerised method of analysing fetal heart rate and uterine activity using a simple algorithm has demonstrated a capability to predict fetal acidosis at the time of delivery. Further research in this area is warranted.

Acidosis↗
PubMed1995

A prospective study of the microbiological environment of the genitourinary tract in Hong Kong Chinese women during pregnancy.

Microbiological colonization of the genitourinary tract in pregnancy is associated with an increased risk of preterm labour and delivery. In our population, the risk of preterm labour is relatively low, and the purpose of this study was to examine the microbiological environment of the genitourinary tract to determine whether it differed from that reported in populations where the rate of preterm delivery is higher. A prospective study was made in 367 unselected women between 16 and 24 weeks' gestation. Although the rate of colonization with Candida species was higher than in most other studies (30.2%), colonization with Gardnerella, Group B Streptococcus, Trichomonas and Chlamydia was uncommon (1.9%, 0.8%, 0.6% and 3.5% respectively). Significant bacteriuria was also uncommon, occurring in only 4.9% of cases. The results of this study confirmed a relatively low incidence of colonization of the genitourinary tract in this population of women with a low incidence of preterm delivery. These findings suggest that low levels of colonization may be related to a low incidence of preterm delivery in our patients.

Adult↗
PubMed1995

Prevalence and significance of HER-2/neu amplification in epithelial ovarian cancer.

Amplification of the HER-2/neu oncogene was assessed in 80 cases of epithelial ovarian tumors using differential polymerase chain reaction. HER-2/neu gene was amplified in 22 of 46 invasive cancers (48%) and in 5 of 34 borderline cancers (15%), but none of the 20 specimens of normal ovaries showed amplification. THis difference is statistically significant (p = 0.00004). The incidence of HER-2/neu amplification in late stage (III-IV, 77%) was significantly higher than that in early stage (I-II, 21%) in invasive epithelial carcinoma (p = 0.0004). There was no correlation between HER-2/neu amplification and cell type or grade of tumor. In cases of ovarian tumors of borderline malignant potential, the amplification of HER-2/neu was not correlated with clinicopathologic features. Follow-up with a mean of 22 months (6-50 months) was available for 39 cases of invasive ovarian cancers and all 34 borderline ovarian cancers. The incidence of HER-2/neu amplification in the invasive cancer and borderline cancer patients who were alive with disease was 50 and 50%, and is not statistically different from that in the patients who were alive with no evidence of disease (p = 0.662 and 0.345, respectively). The incidence of amplification in the invasive cancers of patients who died of the disease (86%) was higher than that in the patients who were still alive (44%), but the difference is not statistically significant (p = 0.175). This study supports the association of HER-2/neu amplification with progression of invasive ovarian cancer. It also suggests that HER-2/neu amplification may be an adjunctive prognostic factor of invasive epithelial ovarian cancer, shown to be associated with an unfavorable clinical course. In addition, HER-2/neu amplification occurs relatively infrequently in early invasive and borderline ovarian cancers, making it unlikely that such amplification is a general early event in ovarian carcinogenesis.

Base Sequence↗
PubMed1995

Sonographic assessment of the vaginal vault following hysterectomy.

OBJECTIVE: A prospective study to determine the sonographic appearance of the vaginal vault following hysterectomy. METHODS: A transvaginal sonographic examination of the vaginal vault on the third postoperative day. Follow-up to determine the incidence of postoperative morbidity. RESULTS: An accurate sonographic examination of the vaginal vault was possible in 66/71 cases (92.9%). Fluid collections were visible in 28/66 cases (42.4%), and measured up to 41.1 cm2 in the transverse plane and 30.2 cm2 in the sagittal plane. There was no correlation between the presence of a collection and indices of postoperative morbidity. CONCLUSION: Collections of fluid at the vaginal vault are common after hysterectomy, but do not usually contribute to postoperative morbidity.

Exudates and Transudates↗