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Biomedical subjects

H K Ma

Publications and source records attributed to H K Ma.

At least 37 records · Page 2Linked to original sources
PubMed1994

HPV and p53 in cervical cancer.

OBJECTIVE: To determine the prevalence of HPV 16 and 18 E6 by DNA detection and p53 abnormal protein expression in cervical cancers in Hong Kong. MATERIALS AND METHODS: Seventy-three squamous cell cervical cancer biopsy were analysed. Detection of HPV DNA was carried out by the polymerase chain reaction and Southern blotting (PCR/SB) technique using primers to the HPV16 & 18 E6 region and consensus primers to the L1 region. Abnormal expression of the p53 protein was detected by immunohistochemical staining (IHS) using the antibody CM1 on frozen sections of 55 cervical cancer samples. Forty-six samples were analysed for both the presence of HPV DNA and abnormal expression of p53. RESULTS: 67.2% of the 64 samples showed the presence of HPV 16 E6 DNA and 39.1% showed the presence of HPV 18 E6 DNA. 32.8% showed the presence of both HPV 16 and 18 E6 DNA. No HPV DNA was shown in 10.9% of samples. Only 3.6% (2) of 55 samples showed positive IHS with CM1. One occurred in a HPV negative sample and the other in a HPV positive sample. CONCLUSION: A high prevalence of HPV DNA was detected in cervical cancer in Hong Kong using the PCR/SB technique. However, abnormal expression of p53 was uncommon amongst patients with or without HPV 16 or 18 infection.

Base Sequence↗
PubMed1994

Expression of the p53 gene in trophoblastic cells in hydatidiform moles and normal human placentas.

In this study we compared the expression of p53 in six early placentas and eight hydatidiform moles using Northern blotting. A higher expression of p53 in hydatidiform moles as compared to normal placentas of comparable gestational age was observed. Immunohistochemical studies did not detect mutant protein of p53 in the hydatidiform moles. DNA sequencing was performed on four of the hydatidiform moles with increased expression of p53, but no mutations could be detected. The possible role of p53 in the pathogenesis of hydatidiform mole is discussed.

Base Sequence↗
PubMed1993

Dose-tumor response of carcinoma of cervix: an analysis of 594 patients treated by radiotherapy.

This is a retrospective study of 594 histologically proven carcinomas of the uterine cervix treated with radiotherapy alone between January 1970 and December 1986. The age of this group of patients ranged from 22 to 86 years, and the median age was 57 years. There were 544 (91.6%) patients with squamous carcinoma and 36 (6.1%) with adenocarcinoma. There were 24 (4.0%) patients who were treated by two sessions of intracavitary brachytherapy only using intrauterine tandem and vaginal ovoids; 513 (86.4%) patients received whole pelvis irradiation followed by two sessions of brachytherapy at 1-week intervals, with or without additional boost to the parametrium. The dose to point A ranged from 40 to 100.9 Gy for the patients with stage IB to IIIB disease. The 5- and 10-year survival for stages IB, IIA, IIB, IIIA, and IIIB were 90.0, 82.1, 72.0, 50.0, 51.5, and 86.9, 71.0, 67.5, 41.7, and 46.9%, respectively. There was no long-term survivor for stage IV disease; the median survivals for patients with stages IVA and IVB were 15.2 and 9.3 months, respectively. Dose response was demonstrated for stages IIB and III tumors; dose to point A greater than 85 Gy was associated with better central control (P = 0.0036 and 0.0234, respectively). However, further increase in dose to point A beyond 85 Gy was not associated with improvement in central control (P = 0.3128 and 0.3394, respectively, for stages IIB and III). It was also found that the occurrences of rectosigmoid and bladder complications were correlated with the rectal and point A dose. Thus, for these patients, there is no need to increase the dose to point A beyond 85 Gy so that the risk of radiation sequelae can be cut down.

Actuarial Analysis↗
PubMed1993

Termination of second trimester pregnancy with sulprostone and mifepristone: a randomized double-blind placebo-controlled trial.

A prospective randomized double-blind placebo-controlled trial was conducted in 13 subjects to find out whether mifepristone treatment could facilitate termination of second trimester pregnancy by sulprostone. The women received either 600 mg oral mifepristone or placebo tablets 36 hours before the administration of intramuscular sulprostone 0.5 mg every 6 hours. The median interval between the administration of sulprostone and abortion in the mifepristone group (4.6 hours) was significantly shorter than that in the placebo group (20 hours). The amount of sulprostone required was also significantly less in the mifepristone group. There was no significant difference in the incidence of side effects or analgesic requirement between the two groups. We conclude that oral mifepristone is useful in facilitating termination of second trimester pregnancies by sulprostone.

Abortifacient Agents, Nonsteroidal↗
PubMed1993

Blood loss in termination of early pregnancy by vacuum aspiration and by combination of mifepristone and gemeprost.

Blood loss was measured in 17 subjects undergoing surgical termination of pregnancy and in 96 subjects undergoing medical termination of pregnancy with sequential mifepristone (200 mg, 400 mg, 600 mg) and 1 mg prostaglandin analogue gemeprost. The median blood loss were 53.2, 84.1, 99.9 and 101.4 ml, respectively. There was a statistically significant difference between the surgical and each of the medical termination group of subjects but there was no difference among the subgroups in the medical termination group. The pattern of bleeding was also similar, being heaviest on the day and the days shortly after prostaglandin administration. Majority of them (> 90%) experienced blood loss of < 300 ml and there was no significant drop in hemoglobin level during the 6-week follow-up period. A few women experienced heavy bleeding and, hence, strict supervision on medical termination of pregnancy is recommended.

Abortifacient Agents, Nonsteroidal↗
PubMed1993

Shared antenatal care between family health services and hospital (consultant) services for low risk women.

Four thousand four hundred and seventy-two patients were recruited into a project to test the efficacy of a Shared Care System in the management of low risk antenatal patients. The patients were scored according to a simple point scoring system. Three thousand three hundred and fourty-seven (74.8%) were scored as low risk. Fifty point two percent (1,682) of these low risk patients received the conventional system of care and acted as controls; while 49.8% (1,665) received shared care, where they were seen jointly by midwives, general doctors and hospital specialists. It was found that with the use of shared care, there was a significant decrease in workload to the hospital specialty clinics. Not only was the antenatal diagnostic rate of intrauterine growth retardation (IUGR) significantly improved, but the mean gestations at which IUGR, malpresentations, and pregnancy induced hypertension were diagnosed were also significantly earlier. The number of antenatal cardiotocographs performed, as well as the number of hospital admissions and mean duration of stay were decreased in the study group. The overall cost savings to the hospital was calculated if the shared care system was generally adopted.

Adolescent↗
PubMed1993

Use of prophylactic antibiotics in patients with carcinoma of the cervix receiving intracavitary radium insertion.

The efficacy was studied of prophylactic antibiotics in preventing febrile morbidity in patients with carcinoma of the cervix undergoing intracavitary radium insertions. Of 93 consecutive patients who had completed external irradiation and two intracavitary radium insertions, 63 (67.74%) had fever over 37.5 degrees C and 19 (20.43%) had fever over 38 degrees C during radium insertion when prophylactic antibiotics were not given. When 3 gm cefoxitin was given over 24 hrs in divided doses as prophylaxis, 39 (41.93%) had fever over 37.5 degrees C and 8 (8.60%) had fever over 38 degrees C. The difference was found to be statistically significant for fever over 37.5 degrees C (p < 0.001) and fever over 38 degrees C (p < 0.05). There was no difference in the duration of fever in the two groups, but the use of antibiotic prophylaxis apparently decreased the need for subsequent therapeutic antibiotics from 13.98% to 4.30%. No difference in the febrile incidence was found when considering the size of the cervical tumour, the stage of the disease, or whether it was a first or second radium insertion, or whether the patient had her menopause already. Prophylactic antibiotics were also found to be more effective in preventing febrile morbidity over 37.5 degrees C in those receiving adjuvant chemotherapy as compared to the general study group (p < 0.025). We concluded that the use of prophylactic antibiotics has beneficial effect in decreasing febrile episodes during the period the radium was inserted, as well as in reducing subsequent need for therapeutic antibiotics, while its use in immunocompromised patients who are prone to sepsis may also be of advantage.

Adult↗
PubMed1992

Clinical significance of mucin production in post-irradiated cervical carcinoma.

Histological sections from 50 patients with clinical stage Ib to stage IIb squamous cell carcinoma of the cervix, initially treated by radiotherapy and followed by Wertheim hysterectomy, were reviewed and stained for mucin. The tissues from 17 (34%) of the patients contained no residual carcinoma. Mucin production was demonstrated in tumour tissue from 18 (55%) of the patients with residual tumour, none of who died of disease during the 5 to 10 years of follow up. Two patients who died of recurrent carcinoma had no mucin production in the post-irradiated tumour tissues. The presence of mucin in irradiated carcinoma of cervix seems to infer a better prognosis and this may prove useful in the follow-up of irradiated carcinomas.

Adult↗
PubMed1992

Born before arrival--uncovering the hazards.

In a retrospective case controlled study the demographic background and outcome of 193 mothers whose babies were born before arrival at hospital was compared to that of a control group who delivered within the maternity units of 2 teaching hospitals in Hong Kong. Mothers who delivered before arrival at hospital were significantly more likely to be single, to have received no antenatal care, to have an unplanned pregnancy, low family income and to come from a socially disadvantaged group such as Vietnamese refugees and illegal immigrants from China. Lacerations to the genital tract, postnatal anaemia and blood transfusions were more common in the study group. Results of cervical cytology and rubella status were available in significantly fewer of these mothers. They were more likely to be ambivalent about contraception and less likely to attend the postnatal clinic. The perinatal mortality and morbidity was significantly increased.

Adolescent↗
PubMed1992

The effect of smoking during pregnancy on the incidence of low birth weight among Chinese parturients.

The incidence and effect of smoking in Chinese parturients are not well known. In a retrospective case-controlled study of 213 patients who smoked during pregnancy, it was found that the incidence of low birth-weight was doubled. On average the babies were smaller by 200 g, shorter by 1 cm and the head circumference was smaller by 0.3 cm. These anthropometric deficits may have significant long-term effects. Although the incidence of smoking in Chinese parturients is low (2%), the rising trend in recent years should prompt all physicians to advise expectant mothers to avoid smoking before and during pregnancy.

Adult↗
PubMed1992

Narcotic addiction in pregnancy with adverse maternal and perinatal outcome.

A retrospective case controlled study was carried out on 51 Chinese gravidas who had abused narcotics and who were delivered in a teaching hospital in Hong Kong. Heroin was the most commonly abused drug. The number of patients who changed from heroin to methadone was small. The major antenatal complications were late antenatal booking (average 28 weeks), prematurity (41%), small for gestational age baby (27.5%), antepartum haemorrhage (13.7%) and high prevalence of venereal disease (23.5%). The babies born to drug addicted mothers were on average 629 g lighter at birth, 5 cm smaller in head circumference and 7 cm shorter in body length. Neonatal withdrawal symptoms occurred in 83% of all drug exposed neonates. The perinatal mortality rate was 19.6 per 1,000 total birth which was 2.5 times that of the control group. There was one maternal death in our series. Drug addiction in pregnancy poses a major risk to both mother and child.

Adult↗
PubMed1991

Discrepancy between laboratory determination and visual estimation of blood loss during normal delivery.

Blood loss during normal delivery was measured in 37 primiparas and 25 multiparas who had no obstetric or medical complications and who underwent normal delivery in a teaching hospital following spontaneous onset of labour at term. Measured blood loss was significantly greater than the estimated volume of blood loss. In primigravidas, the mean ( +/- SE, standard error of the mean) estimated blood loss was 260 +/- 12 ml and the mean measured blood loss was 401 +/- 29 ml. In multiparas the mean estimated blood loss was 220 +/- 10 ml and the mean measured blood loss was 319 +/- 41 ml. The mean estimated blood loss was significantly lower (P less than 0.05) than the mean measured blood loss in both groups. The size of the discrepancy between measured and estimated blood loss was proportional to the measured blood loss. These findings show that visual estimation of blood loss was grossly inaccurate.

Adult↗
PubMed1991

Primary mixed neuroendocrine and mucinous carcinoma of the ovary.

A rare case of mixed carcinoma of ovary with a predominant malignant neuroendocrine and a lesser mucinous tumor component is described. Extensive areas of enteric-type epithelium containing endocrine cells were present in both the mucinous borderline tumor element and in the small foci of mucinous adenocarcinoma. Transition from the mucinous tumor to the malignant neuroendocrine component provides evidence for the derivation of some neuroendocrine or carcinoid tumors direct from mucinous tumors without necessarily being a component of a teratoma. Contrary to reported examples of mucinous carcinoid, the overgrowth and spread of the neuroendocrine component characterised the aggressive and lethal nature of this tumor.

Adenocarcinoma, Mucinous↗
PubMed1991

Grand multiparity: a reappraisal of the risks.

An excellent maternal and perinatal outcome is reported in a group of grand multipara of low socioeconomic status. These observations on a group of patients who are traditionally considered to be high risk show that in a healthy population with access to modern medical care and hospital delivery, a favorable outcome can be achieved despite a low socioeconomic or refugee status.

Adult↗
PubMed1991

A case controlled study of pregnancy complicated by severe maternal anaemia.

The perinatal outcome of 96 patients who had an antenatal haemoglobin value of less than 8.0 g/dl was compared with that of a similar number of controls who were matched for age and parity. Sixty-one patients (63%) had iron deficiency anaemia, 25 (26%) had alpha or beta thalassaemia minor, 7 (7.3%) had iron deficiency and thalassaemia trait, 2 had idiopathic pancytopenia and 1 had haemolytic anaemia due to systemic lupus erythematosus. Patients in the study group attended the antenatal booking clinic later, had less weight gain during pregnancy and their babies had lower birth-weights (2,984 g versus 3,177 g p less than 0.01) although there was no significant difference in the period of gestation at delivery. Six patients in the study group had placental abruption and another 2 patients had stillbirths but neither of these complications occurred in the control group. Although 37 patients (39%) in the study group received an antenatal blood transfusion, 53 (55%) of this group also had postnatal anaemia.

Adolescent↗
PubMed1991

The impact of multiple induced abortions on the outcome of subsequent pregnancy.

The obstetric outcome of 285 women with a history of previous multiple induced abortions is compared to that of 285 age matched primigravidas. In the study group, 219 women had 2 previous induced abortions and 66 had 3 or more, the maximum number being 8. There was a higher incidence of unmarried women and smokers in this group but a lower incidence of uneducated women. There was no difference in the incidence of antenatal complications between the 2 groups. The mean gestation at delivery, duration of labour and mode of delivery were comparable. There was an increased incidence (p less than 0.01) of retained placenta in the subgroup of women with 3 or more previous induced abortions. There were no maternal or perinatal deaths. The mean birth-weight was comparable and there were no infants weighing less than 1,500 g in either group. We conclude that multiple previous induced abortions appear to have minimal impact on the obstetric outcome of subsequent pregnancy in this population, and in the absence of other risk factors there is no need to alter standard obstetric management in this group of women.

Abortion, Induced↗
PubMed1990

A controlled trial of bestatin in hydatidiform mole.

A prospective randomized controlled trial was conducted to study whether Bestatin, an immunomodifier, can reduce the incidence of persistent gestational trophoblastic disease in patients with hydatidiform mole. A group of 21 patients (Bestatin group) received 30 mg Bestatin daily after evacuation of the hydatidiform mole. A second group of 23 patients (control group) did not receive any drug. Blood was taken for white cell counts, differential counts, lymphocyte subset counts (CD2+, CD4+, CD8+ and B cells) and natural killer cell activity before evacuation of the hydatidiform moles. The tests were repeated every 4 weeks after evacuation until the serum beta subunit of human chorionic gonadotropin (beta hCG) had returned to normal or until the patient had to receive chemotherapy because of persistent gestational trophoblastic disease. There was no significant difference in the age of the patients, the pre-evacuation serum beta hCG, or the gestational age between the two groups. Chemotherapy was needed by 6 patients in the Bestatin group (28.6%) and 3 patients in the control group (13%) because of persistent gestational trophoblastic disease. There was no significant difference in any of the immunological parameters between the two groups before or after evacuation. We conclude that Bestatin at this dosage does not improve the immunological functions or clinical outcome in patients with hydatidiform mole.

Adjuvants, Immunologic↗