Different levels of immunity to Schistosoma mansoni in the mouse: the role of variant cercariae

Very variable levels of immunity to a second infection with Schistosoma mansoni were recorded in 7 strains of mice, 12--15 weeks following a small primary infection. When 2 or more strains of mice were assayed at the same time, less variation occurred within the experiment than between different experiments. This evidence suggested variation between pools of cercariae as the main cause of variability in immunity. In direct experiments in one strain of mouse, 2 different pools of cercariae stimulated widely different levels of immunity to the same challenge. Conversely, challenge infections drawn from different pools showed different susceptibility to immunity stimulated by the same primary infection. Individual clones of cercariae, from snails infected with single miracidia, showed a high level of susceptibility to immunity stimulated by a small bisexual infection, or were not susceptible at all. Antigenic polymorphism is the most likely explanation for the differences observed between clones of cercariae. However, indirect immunofluorescence showed the presence of at least 1 common antigen on the surface of schistosomula derived from different clones of cercariae and clone-specific antigens have not been detected.

Relationship between urinary and blood glucose in diabetic children

The relationship of urine glucose concentration with 'average' blood glucose concentration for the corresponding period was investigated in 10 juvenile diabetics during the performance of 15 inpatient metabolic profiles. 0% glucosuria was associated with 'average' blood glucose concentrations less than 6.4 mmol/l (less than 115 mg/100ml), 2% glycosuria with concentrations greater than 8.6 mmol/l (greater than 154 mg/100ml), and over 5% glycosuria with concentrations greater than 11.3 mmol/l (greater than 204 mg/100ml). Urinary glucose loss was large (greater than 278 mmol; greater than 5g) when the 'average' blood glucose was greater than 11.1 mmol/l (greater than 200 mg/100ml). Because many diabetics have blood glucose concentrations up to 11.1 mmol/l, it is advantageous if glucosuria up to 5% is detectable by routine home urine tests. The 2-drop Clinitest method detects glycosuria up to 5% without significant loss of accuracy and is recommended in preference to the 5-drop method.

Development of apparatus to measure calcium changes in the forearm and spine by neutron activation analysis using californium-252

Techniques were developed to measure small changes of calcium in the forearm and spine in vivo by neutron activation analysis using two sources of 252Cf in a hospital environment. Using purpose-built part-body counters and bilateral irradiation with 7.5 cm premoderation between the sources and the bone, peripheral bone was measured with a total source strength eventually as low as 50 mCi. Two methods of spectral analysis were used and compared. Patient studies of the forearm were successfully undertaken, with a precision of 2.6% which included patient movement, and an annual bone dose of less than 10 rem and skin dose of 35 rem from six measurements. Two 100 mCi sources were used for measurements of the lumbar spine. Care was taken to minimise the problems of non-uniformity of activation which are present using unilateral irradiation. Emphasis was placed on measuring the bodies of the vertebrae with adequate sensitivity and uniformity, and the spinous processes and arches with low sensitivity. A whole body counter was used for the bilateral detection of the induced activity. The precision of the method was 3.0% with an annual peak bone dose of 2.1 rem and skin dose of 18 rem from three measurements.

Reduction of insulin dose on changing diabetic children from standard to monocomponent insulins

21 diabetic children requiring greater than 50 units of standard insulin daily were changed to a monocomponent insulin. During the 3 months before the change the insulin dose had risen significantly from a mean of 70 to a mean of 77 units daily. During the 3 months after the change the dose fell significantly to a mean of 53 units daily. This decrease in insulin requirement was associated with a general improvement in diabetic control. This was assessed clinically and measured in 10 children by an analysis of home urine tests and in 8 children by an analysis of 24-hour urine glucose excretion.

Effect of temperature on protein synthesis in fish of the Galapagos and Perlas Islands

1. The temperature dependency of protein synthesis was studied in vivo in five species of Pacific fish collected in the Galapagos and Perlas Islands: batfish (Ogcocephalus darwini), groupers (Epinephelus labriformis), catfish (Netuma platypogan), puffers (Arothron hispidus) and triggerfish (Sufflamen verres). 2. Liver protein synthesis, assayed by a rapid pulse injection technique, showed a moderate temperature dependency (Q10 = 2-3) in the 15-30 degree C range for all species except puffers (Q10 = 10-20). Synthesis was inhibited above 32 degrees C. 3. Protein synthesis in triggerfish was measured by the constant-infusion technique. Synthetic rates (% of tissue protein synthesized per day) at 25 degrees C were 20% for liver, 10% for gill, 1.8% for red muscle and 0.6% for white muscle. Q10 in the 20 degrees-30 degrees C range was 3.0 +/- 0.5 degrees C for all tissues.

Oestrogen and pregnanediol excretion through childhood, menarche and first ovulation

Urinary oestrogen and pregnanediol values were measured in 24 boys and 38 girls between the ages of 2 and 13 years. Longitudinal studies were conducted on eight girls, two of whom collected for periods of 4 and 5 years which included menarche and in one case establishment of ovulation. Highly sensitive assay methods were developed for measuring the very small amounts of oestrone, oestradiol and oestriol and pregnanediol present in the urine of young children. The total oestrogen values were within the submicrogram range of 0·1–0·5 μg/24 hr in the children aged 2–8 years, with no differences seen between the boys and girls. After the age of 8 years, oestrogen values above 1 μg/24 hr began to be encountered and by age 11½ years the majority of subjects were recording oestrogen values above this figure. The rise in the oestrogen values was more rapid in the girls than in the boys. Evidence was presented that a value of approximately 1 μg/24 hr represents the minimum oestrogen production for the initiation of breast development. The oestrogen values were fluctuating with irregular periodicities at all ages and the gradual general rises seen after the age of 8 years could be arrested at any stage for a year or more. Menarche was preceded by marked periodic fluctuations in oestrogen output which peaked above 15 μg/24 hr. In all subjects studied, the initial bleeding cycles were anovulatory as judged by the low pregnanediol values, the usual pattern being one of fluctuating oestrogen production. One subject was studied fully through to the establishment of ovulation, which first occurred 12 months after menarche. The approach of ovulation was indicated by pre-menstrual rises in pregnanediol which increased in amplitude from 0·4 mg/24 hr until finally 2 mg/24 hr was exceeded (the value accepted for ovulation). Evidence was presented that the interval from menarche to ovulation in different individuals was very variable, extending from ovulation at menarche itself to periods of more than a year. Recording of self-observed symptoms of production of cervical mucus could be of considerable value in documenting these events in larger populations.

Corpus luteum function in early pregnancy following ovulation induction with bromocriptine

Serum and prolactin levels and urinary oestrogen and pregnanediol excretion were measured during early pregnancy in 12 hyperprolactinaemic subjects who became pregnant during treatment with bromocriptine. Prolactin levels were suppressed below normal whilst taking the bromocriptine, but rose significantly when this drug was stopped and by eight weeks of gestation reached values significantly higher than those observed in normal pregnancy. Further increases in prolactin levels were, however, not observed. Urinary oestrogen and pregnanediol excretion was initially normal but, following cessation of bromocriptine, urinary pregnanediol excretion decreased and was significantly less than normal at 11 to 14 weeks gestation. These results suggest that elevated prolactin levels affect corpus luteum function of early pregnancy. Because the effect is maintained until at least 14 weeks gestation, prolactin may also affect progesterone production by the placenta.

The effect of dialysate calcium concentration on 1alpha-hydroxyvitamin D3 on skeletal calcium loss and hyperparathyroidism in haemodialysis patients

The response of hyperparathyroidism and skeletal calcium loss in haemodialysis patients to treatment with 1alpha-hydroxyvitamin D3 and a dialysate calcium concentration of 1.375 mmol/l was compared with the response to treatment with a dialysate calcium concentration of 1.375 or 1.75 mmol/l alone over a 6 month period. In patients treated with 1alpha-hydroxyvitamin D3 there was a significant rise in plasma calcium associated with a significant fall in plasma alkaline phosphatase and plasma parathyroid hormone as well as resolution of sub-periosteal erosions. In these patients there was a significant rise in the calcium content of the forearm assessed by neutron activation analysis in comparison to patients treated with a dialysate calcium concentration of 1.75 or 1.375 mmol/l alone. In patients treated with a dialysate calcium concentration of 1.375 or 1.75 mmol/l alone there was no significant change in the plasma calcium, alkaline phosphatase or parathyroid hormone after 6 months and in these patients subperiosteal erosions either did not change or became worse. No significant difference in the response in these two groups was observed. This study indicates that treatment of haemodialysis patients with 1alpha-hydroxyvitamin D3 is significantly more effective than treatment with a dialysate calcium concentration of 1.375 or 1.75 mmol/l alone in preventing progression of hyperparathyroidism and skeletal calcium loss.

A study of the effects of bromocriptine on serum prolactin, follicle stimulating hormone and luteinizing hormone and on ovarian responsiveness to exogenous gonadotrophins in anovulatory women

Twelve anovulatory patients with normal serum prolactin values and six with elevated values were treated with bromocriptine and the effects on serum prolactin, FSH and LH levels were recorded. Ovulation resulted in one patient who had normal prolactin values and in all six who had raised values. No patient with normal basal prolactin values showed an increase in serum FSH during therapy with bromocriptine, whereas 5 of the 6 patients with elevated values showed significant increases. Similar results were obtained for LH. Although these differences were highly significant (P less than 0-005) the majority of the serum FSH and LH values remained within the normal ranges. Five patients with normal basal prolactin values and one with elevated values were also treated with human pituitary gonadotrophin (HPG). An increase in ovarian responsiveness to HPG during therapy with bromocriptine was recorded in the one patient with initially elevated prolactin values. It was concluded that bromocriptine acts by allowing FSH to rise above threshold requirements for follicular stimulation.

Oestrogen excretion and ovarian pathology in postmenopausal women with atypical hyperplasia, adenocarcinoma and mixed adenosquamous carcinoma of the endometrium

Urinary oestrogen and pregnanediol excretion were measured before and after hysterectomy and bilateral salpingo-oophorectomy in 26 postmenopausal women with adenocarcinoma of the endometrium, 10 postmenopausal women with mixed adenosquamous carcinoma and 11 postmenopausal women with atypical hyperplasia (the patient groups). The results were compared with the values obtained in 22 active postmenopausal women, 20 hospitalized postmenopausal women and 18 women who had been subjected to hysterectomy and bilateral salpingo-oophorectomy for cancer of the cervix (the control groups). The ovaries and Fallopian tubes obtained at operation were examined for evidence of current or past excessive oestrogen production. Preoperative oestrogen values were higher in the patient groups than in the controls and the elevated values persisted after oophorectomy. The implications of these findings are discussed.

Serum prolactin levels in normal women and in women with disorders of menstruation

The mean (+/-SD) serum prolactin (PRL) level of 78 normal premenopausal women was 10-6+/-3-0 ng/ml, and this was significantly different from that of post-menopausal women (8-2+/-4-0 ng/ml) and women taking combined oral contraceptive preparations (12-2+/-4-0 ng/ml). No significant differences were found between follicular and luteal phase PRL levels. Serum PRL levels higher than the ranges given above were found in 31 of 87 patients with secondary amenorrhoea and two of 41 patients with oligomenorrhoea. Nine of the 33 patients with hyperprolactinaemia did not have galactorrhoea. Only two of the patients with hyperprolactinaemia had pituitary tumours evident on skull X-ray films. Serum PRL levels were of value in predicting the likely success in achieving ovulation with clomiphene citrate or CB-154; clomiphene citrate was less likely to be successful in the presence of hyperprolactinaemia, whereas the reverse applied for treatment with CB-154.

Serum prolactin levels and the value of bromocriptine in the treatment of anovulatory infertility

Basal serum levels of prolactin were measured in 37 infertile anovulatory patients who had failed to conceive on therapy with clomiphene citrate. Twenty of these patients, 16 of whom had galactorrhoea, had elevated basal serum prolactin values which were suppressed to normal or subnormal values during therapy with bromocriptine, the most commonly effective dose being 2.5 mg twice daily. Ovulation, as assessed by urinary oestrogen and pregnanediol measurements, was induced in 17 of these patients with pregnancy in 14. Ovarian responses short of defined criteria for ovulation were induced initially in eight patients, but these progressed to full ovulatory responses in five patients, either on the same or increased doses of bromocriptine. In all the patients who ovaulated, the prolactin levels had been reduced below the mean value for normal women (10.6 ng-ml). The three patients who failed to ovulate all had values higher than this at a dose of bromocriptine reaching 5.0 mg thrice daily. There seemed to be no value in increasing the dose of bromocriptine once ovulation had been achieved. Of the 17 patients with normal basal prolactin values, only one had an unequivocal response to bromocriptine with ovulation and conception, even though the prolactin values in the majority were suppressed to below normal.

Different levels of acquired immunity to Schistosoma mansoni in two strains of hamster

A primary infection with schistosoma mansoni, of 5 or more weeks duration, stimulated a high level of resistance to a challenge infection in the WO outbred strain of golden hamster. In sharp contrast, the LGN strain showed no statistically significant immunity to reinfection in most experiments and where detected the level of resistance was only about half that observed in the WO strain. Immunity to reinfection was assayed with the lung recovery method which assesses resistance a few days after challenge and with the conventional perfusion assay which measures immunity 6 weeks after challenge. Wide differences in the immune response to S. mansoni in different strains of the same host species have not been reported previously.

Preparation and characterization of antithymocyte serum and globulin without stem cell activity

Immunosuppressive antimouse and antihuman thymocyte sera and antihuman T lymphocyte sera, raised in rabbits, inhibited colony formation in vitro by bone marrow stem cells. Absorption of the antisera with fetal liver, or isolation of the gamma-globulin from the antisera, removed the inhibitory effect on bone marrow stem cells but left the anti T lymphocyte activity unimpaired. Absorption with cultured lymphoblasts (B cell lines) failed to remove the affinity of the globulins for B lymphocytes.

Cross-immunity to Schistosoma mansoni and S. haematobium in the hamster

Hamsters (WO strain) with a primary infection of Schistosoma mansoni or S. haematobium rapidly developed immunity to homologous challenge judged by the lung recovery assay. Immunity was detected at 4-5 weeks and reached a plateau 6 weeks after infection. Using this information, hamsters with an 8-week primary infection with S. mansoni or S. haematobium were tested for resistance to homologous reinfection and resistance to a challenge with the other species of schistosome. Primary infection with S. mansoni or S. haematobium conferred a high level of immunity to reinfection with either species of schistosome judged by the perfusion assay, involving recovery of adult worms 6-10 weeks following challenge. Estimation of the level of immunity with the lung recovery assay, 5 days after challenge, indicated that immunity due to a primary infection with S. mansoni acted at or before migration of the challenge through the lungs but immunity stimulated by a primary S. haematobium infection was only partially effective at the lung stage and substantial destruction of challenging organisms occurred at a later stage of development. Antibodies in immune sera of hamsters with a primary S. mansoni or or S. haematobium infection were shown to bind to common antigens on the surface of young schistosomula of either species by u.v. microscopy using as detecting agent a fluorescein-labelled rabbit antiserum directed against hamster globulins.

Carcinoma of the colon in a child

A case of mucinous adenocarcinoma of the colon in a 12-year-old girl is reported. There was no evidence of pre-existing familial polyposis or ulcerative colitis, conditions which predispose to colon carcinoma in childhood. A review of the literature revealed 103 previously reported cases. The salient features of the disease are discussed.

Multiple colonic stricture formation and amoebiasis. A case report

Case reports of multiple colonic strictures resulting from amoebiasis are uncommon in the literature. Such a case is presented and the diagnosis and management are discussed.

Early neonatal hypocalcaemia

In our hospital early neonatal hypocalcaemia is now the major cause of low serum calcium in the neonatal period. Over a 2-year period, only 2 cases of hypocalcaemic convulsions were seen in a total of 8700 deliveries, though 51 infants had early neonatal hypocalcaemia. All sick low birth-weight infants should have daily serum calcium estimations carried out. Calcium supplements should be considered if symptoms of hypocalcaemia are present.

Glutaraldehyde and human T cell rosettes

Blood mononuclear cells from ten healthy donors and cells from fifty cultured human lymphoblastoid lines were tested for the capacity to form rosettes with sheep erythrocytes. The effect of adding glutaralhehyde before scoring rosettes and the effect of substituting glutaraldehyde-fixed for fresh sheep cells were both examined. The results suggest that glutaraldehyde increases the apparent proportion of rosette-forming cells by altering the sheep erythrocytes in such a way that they will adhere to some B lymphocytes. Although a small number of cells carry both surface immunoglobulins and receptors for fresh sheep erythrocytes, the rosette test with fresh sheep cells identifies T lymphocytes more accurately in the absence of glutaraldehyde than in its presence.

Early averaged electroencephalic responses to clicks in neonates

The early (approximately 8–50 msec latency) averaged electroencephalic responses (AER) to 55 dB HL clicks were elicited from ten normal newborns 36 to 72 hours after birth. Early components were observed in all ten babies with 512 clicks presented at 4.5/sec and 9.0/sec. Mean peak latencies in msec were: Po — 11, Na — 17, Pa — 28, Nb — 35, and Pb — 51. The neonates' early component waveforms closely resemble those of adults. The latency and waveform stability of the early components in neonates and adults support the belief in the primary auditory (lemniscal) system as the mediator of these responses. Furthermore, the repeatability of the early components of the AER makes them more reliable response indices than the late components (approximately 50–400 msec) for audiometry with neonates.