Adoption in utero is the wrong term.
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Biomedical subjects
Publications and source records attributed to S S Ratnam.
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A sensitive staining method for the detection of oxytocinase (EC 3.4.11.3) activity in electrophoresis gels has been described. The method is based on the enzymatic release of p-nitroaniline (PNA) from two specific synthetic oxytocinase substrates, S-benzyl-L-cysteine-p-nitroanilide (BCN) and L-leucine-p-nitroanilide (LN), respectively. The PNA is then diazotized with sodium nitrite and subsequently coupled to a chromogen, N-(1-naphthyl)-ethylenediamine dihydrochloride (NED) to produce a deep pink/magenta colored azo-dye at the site of oxytocinase activity.
Five homogenates of human sperm cells were separately incubated with [14C]arachidonic acid in the presence of reduced glutathione, L-tryptophan, and haematin as cofactors. The cyclooxygenase products of arachidonic acid metabolism were extracted, separated, and measured for their radioactivity. The rate of formation of prostaglandin (PG)D2, PGE2, PGF2 alpha, 6-keto PGF1 alpha, and thromboxane (TX)B2 were 18.0 +/- 1.11, 10.9 +/- 0.68, 5.8 +/- 0.21, 3.9 +/- 0.13 and 6.6 +/- 0.52 pmol/10(6) cells/min, respectively. These results are discussed in relation to the hypothesis that cyclooxygenase metabolites of certain polyunsaturated fatty acids play an important part in the sperm acrosome reaction and fertilization.
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PURPOSE: A modified two-step ultrarapid freezing technique was compared to the one-step ultrarapid freezing technique. Two-cell mouse embryos were frozen-thawed using the two freezing protocols, and postthaw cryoprotectant removal was carried out in either a single- or a multiple-step procedure. RESULTS: Statistically similar cryosurvival (96.95-100%) and blastocyst formation rates (87.95-91.47%) were obtained with both freezing groups. In addition, the method of cryoprotectant removal did not have any significant effect on the survival and development of the frozen-thawed embryos in both groups. Blastocysts formed following single-step cryoprotectant removal had significantly lower inner cell mass counts in the one-step than in the two-step group (26.14 and 27.59, respectively; P < 0.05). Embryo transfer studies showed that the implantation and fetal formation rates of embryos frozen by the two-step technique (61.67 and 60.0%, respectively) were similar to those of embryos frozen by the one-step technique (74.12 and 71.76%, respectively). CONCLUSION: These results demonstrate that the ultrarapid two-step technique is as effective in cryopreserving two-cell mouse embryos as the ultrarapid one-step technique.
A randomized double-blind study of the metabolic effects of 2 low-dose combined oral contraceptives was carried out in Singaporean women. The subjects comprised 58 women randomly allocated to two treatment groups (29 each): norethisterone 1 mg/ethinyl estradiol 35 micrograms (NET/EE) or levonorgestrel 150 micrograms/ethinyl estradiol 30 micrograms (LNG/EE) and a control group of 23 women using intra-uterine devices (IUD). Blood samples were taken on admission and at 3 and 12 months after pills or insertion of IUDs. Fasting glucose levels were decreased while 2h glucose and triglyceride were increased throughout the treatment period in NET/EE group [corrected]. LNG/EE group only showed significant increase of 2h glucose at 12 months and decrease of LDL cholesterol at 3 months while total cholesterol was significantly suppressed at 3 and 12 months [corrected]. The atherogenic index, LDL/HDL cholesterol was significantly reduced by 12 months. Both groups had no change in hemoglobin, hematocrit and total protein levels but alkaline phosphatase, bilirubin and aspartate transaminase (SGOT) were suppressed. While NET/EE suppressed albumin significantly, this was not observed with LNG/EE group. However, these differences observed with use of each pill preparations, were not so obvious between treatment groups and control. Changes in total, HDL and LDL cholesterol and SGOT were not significantly different than the IUD group. Furthermore, except for 2h glucose, there was no increase in the number of abnormal parameters after treatment. On the contrary, there was a reduction of abnormal values in most liver function parameters. Thus, except for glucose intolerance, the observed changes in metabolic parameters may not constitute any clinical significance.(ABSTRACT TRUNCATED AT 250 WORDS)
In this study involving 100 women, the metabolic changes seen with Norplant use were evaluated. Besides a significant increase in serum bilirubin, there were no other changes in liver function to suggest possible hepatocellular dysfunction at the end of five years. Even the raised mean levels of bilirubin remained within the normal clinical range for the local population. As regards lipid metabolism, total triglycerides, cholesterol and LDL-cholesterol were decreased through the five years of Norplant use. The HDL-cholesterol showed a significant increase in the first year; it then decreased over the years to its preinsertion level at the end of five years. As a result, the HDL-cholesterol/Total cholesterol - HDL-cholesterol showed a significant increase in the first year and then decreased to almost its preinsertion value at the end of five years. The findings appear to indicate Norplant use not to be contributory to cardiovascular risk. The use of Norplant was not associated with any significant effect on carbohydrate metabolism.
This study describes the effects of Norplant on haemostatic function after 5 years of use in 97 women. There was a decrease in vitamin-K dependent Factors II, V, VII and reduction in fibrinolytic activity at 2 and 4 years of use. Increased platelet numbers and accelerated platelet aggregation were found throughout the 5 years of Norplant use, whilst raised alpha 2-Macroglobulin (a2-M) and antithrombin III (ATIII) antigen level were observed for up to 4 years of use. Prolonged Norplant use does not appear to activate the coagulation system and does not enhance a state of hypercoagulation.
A longitudinal study on one-hundred Singaporean women using Norplant-2 rod implant for contraception and their effects on the haemostatic function was carried out. There was a decrease in vitamin K-dependent Factors II, VII and a tendency towards lowered fibrinolytic activity after prolong use of Norplant-2 rods. The results indicate that the Norplant-2 rod implant system does not contribute towards hypercoagulable state but increased platelets and accelerated platelet aggregation observed will require further study to ascertain whether there is a concomitant increase in platelet activation.
The continuation rate at the end of this five-year clinical study was 60% with no accidental pregnancy occurring throughout the five years. The post-removal conception rate in women desiring pregnancy was 92% at the end of two years. The majority of acceptors described the overall experience with the implants as favourable. In fact, 75% of the women planning to use contraception after removal of the implants were going to use implants again.
The Norplant-2 rod system consists of two silastic rods in which levonogestrel has been incorporated with the polymer. The continuation rate at the end of five year was 62%. No accidental pregnancies occurred throughout the five years of use. The post-removal conception rate in women desiring pregnancy was 70.8% at the end of two years. The majority of acceptors were happy with the rods and 86.8% expressed the desire to have another set of implants inserted following removal of the first set. The study shows the Norplant-2 rod system to be a well accepted method of family planning.
The effect of Norplant-2 rods on liver, lipid and carbohydrate metabolism was evaluated in 100 women using Norplant-2 rods. Besides a significant increase in serum bilirubin, there was no other obvious evidence to suggest any possible hepatocellular dysfunction with the use of Norplant-2 rods. As regards lipid metabolism, decreases in total triglycerides, cholesterol and LDL-cholesterol and HDL-cholesterol were initially seen. These parameters returned to their preinsertion mean at the end of five years. As a result, the value of the HDL-cholesterol/total cholesterol - HDL-cholesterol and LDL-cholesterol/HDL-cholesterol ratios remained around their preinsertion value at the end of five years. All this appears to indicate that the use of Norplant-2 rods is not directly contributory to cardiovascular risk. The use of Norplant-2 rods was not associated with any significant effect on carbohydrate metabolism.
Tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA) and plasminogen activator inhibitors (PAI) are elevated in late pregnancy with t-PA and u-PA remaining so at 6 weeks postnatal. PAI-2 remains at postpartum but was absent by 6 weeks postnatal unlike PAI activity which was absent at postpartum and returned to nonpregnant level at postnatal. The potential fibrinolytic response to stress is much reduced in pregnancy thus increasing the risk of thromboembolism.
Forty patients suspected to have ectopic pregnancy by transvaginal ultrasonography had surgery. 77.5% were confirmed to have ectopic pregnancy and 10% had other abnormal pelvic findings. The transvaginal approach appears to enable us to diagnose ectopic pregnancy at an earlier date, with the earliest diagnosis made at 4 weeks 0 days of amenorrhoea. In cases of confirmed ectopic pregnancy, the presence of a complex adnexal mass was the most common feature seen on transvaginal ultrasound and its predictability of ectopic pregnancy is enhanced by a concomitant finding of an empty uterus (95%) or free fluid in the Pouch of Douglas (94%) in the presence of a positive hCG test. The significance of transvaginal ultrasound features, and the advantages of transvaginal over transabdominal ultrasound, are discussed.
One hundred and forty-three pregnancies conceived by assisted reproductive techniques (ART) from October 1985 to June 1989 in the National University Hospital, Singapore, resulted in 66 deliveries and 89 babies. There were 27 (18.7%) biochemical pregnancies, 44 (30.7%) clinical miscarriages and 6 (4.2%) ectopic pregnancies when total pregnancies were considered. Of those who continued pregnancy to second trimester multiple births occurred in 20 (13.3%) patients. A high incidence of vaginal bleeding and hypertension in pregnancy was noted in 32 (48.5%) patients and 18 (27.3%) patients, respectively. Caesarean section was the method of delivery in 48.5% of patients. Twenty-six (29.2%) babies required admission to the neonatal intensive care unit. All babies except one set of twins delivered at 24 weeks of amenorrhoea survived. Fetal abnormality was noted in 2 cases.
Vesico-rectal fistula is a rare congenital abnormality causing severe early second trimester oligohydramnios. Prenatal diagnosis of such a case is reported here. Ultrasound diagnosis could be aided by transabdominal amnio-infusion and, if necessary, fetal intraperitoneal saline installation. In a karyotypically normal fetus with normal somatic growth, demonstration of normal fetal kidneys together with a functioning urinary bladder, in presence of severe oligohydramnios, is very suggestive of the diagnosis. Since pulmonary hypoplasia is the major cause of neonatal mortality in these cases, restoration of normal amniotic fluid volume by serial amnio-infusion was attempted. Although amnio-infusion is an important diagnostic aid in the evaluation of severe midtrimester oligohydramnios, the role of multiple therapeutic amnio-infusion in improving lung growth remains to be evaluated.
OBJECTIVE: To measure sound pressure level in utero while a vibro acoustic stimulator is applied to maternal abdomen and to calculate whether the estimated effect on fetal cochlea cilia vibration would be hazardous. DESIGN: Prospective descriptive study. SETTING: Labour ward, National University Hospital, Singapore. SUBJECTS: Eight women undergoing induction of labour. INTERVENTION: A hydrophone was introduced via the cervix into the uterus and placed under ultrasound guidance near the fetal ear. Sound pressure was recorded when a vibroacoustic stimulator was applied directly to the maternal abdomen and also when separated by 2 cm of air. MAIN OUTCOME MEASURES: Sound pressure levels in utero. RESULTS: The sound level recorded from the vibrator diaphragm in air was 107 dB at 2 cm and 74 dB at 1 m. The mean sound pressure level in utero was 90.7 dB (range 75-96 dB) when the vibrator was in contact with the abdominal wall and 80.1 dB (range 70-88 dB) when separated by 2 cm of air. CONCLUSIONS: Analysis of factors affecting displacement of cochlear sensing cilia in utero show that, for equal sound pressures, sound intensity and sound vibration are about 4000 times less in amniotic fluid, compared to that produced in air. Further protection is provided by viscous and hydrodynamic features of the ear. The estimated effect on cilia vibration by the mean sound pressure registered in utero, about 90 dB, corresponds to that produced postnatally by an airborne sound registering about 40 dB, which would not be hazardous.