Enhanced potency of truncated insulin-like growth factor-I (des(1-3)IGF-I) relative to IGF-I in lit/lit mice

The relative potencies of insulin-like growth factor (IGF-I) and the N-terminal truncated derivative, des(1-3)IGF-I, have been compared in lit/lit mice. Injection of 30 micrograms IGF-I, 30 micrograms des(1-3)IGF-I or 3 micrograms des(1-3)IGF-I daily for 3 weeks increased total length and nose-rump length of the animals substantially more than in controls or animals treated with 3 micrograms IGF-I daily. Body weight changes were not statistically significant. The lower dose of des(1-3)IGF-I, but not that of IGF-I, led to increases in kidney and heart weights relative to controls, while the higher dose of either IGF-I or des(1-3)IGF-I also increased the weights of liver, lungs and stomach. These results indicate that the higher potency of des(1-3)IGF-I demonstrated in cultured cells also applies in vivo to at least one strain of GH-deficient animals.

A request for antenatal advice

An informed older woman in her first pregnancy often has greater than usual anxieties about the well-being of her baby. She is likely to seek advice about how to have a healthy pregnancy and which antenatal tests to have. Giving the correct guidance, however, is not so straightforward.

Increase in proteinuria and reduction in number of anionic sites on the glomerular basement membrane in rabbits by infusion of human nephrotic plasma in vivo

1. Intraortic suprarenal infusion in vivo of New Zealand White rabbits with plasma from patients with the nephrotic syndrome reduced the number of anionic sites labelled by the cationic polymer polyethyleneimine in the lamina rara iterna to 14.0 +/- 2.7 per 1000 nm of lamina rara interna (mean +/- SD) compared with 18.7 +/- 2.1 (P less than 0.005) after infusion of plasma from normal subjects. 2. Proteinuria increased in all nine animals infused with nephrotic plasma and in two of seven infused with control plasma (P less than 0.01). The mean increase in proteinuria in the animals infused with nephrotic plasma was 246 mg/l (P less than 0.05), whereas in those infused with control plasma there was no increase. 3. We conclude that nephrotic plasma contains a factor(s) capable of neutralizing the charge of these anionic sites and concomitantly increasing proteinuria.

Development, validation and application of computer-linked knowledge questionnaires in diabetes education

Multiple choice questionnaires (MCQs) capable of being marked manually or by a newly developed optical mark reader, or by use of an inexpensive inter-active microcomputer system have been developed for the separate assessment of insulin-dependent and non-insulin-dependent patient knowledge. Forty-six insulin-related and non-insulin-related multiple choice questions covering six main areas of knowledge were constructed for inclusion into draft questionnaires. From the responses of a total of 180 completed questionnaires, piloted in 18 randomly selected clinics in 14 Regional Health Authorities in England, psychometric analysis was performed to determine reliability, discrimination coefficients, and facility indices. Seventy-three per cent of insulin-dependent diabetic patients (IDDM) and 92% of non-insulin-dependent diabetic patients (NIDDM) MCQ correct options had facility indices within the acceptable range of 30 to 90%. 82% IDDM and 93% NIDDM correct options had discrimination coefficients exceeding 0.2. Questionnaire reliability (internal consistency) using the Kudor-Richardson (KR20) formula was IDDM 0.87 and NIDDM 0.82. Evidence in support of the IDDM questionnaire's criterion validity was based on significant differences (p less than 0.05) identified between a number of knowledge area scores stratified according to HbA1 levels. Prescriptive correction for screen display and automatic hard copy feedback was designed for both incorrect and omitted question options, providing both educational (patient) and analytical (clinic) documentation. Both technical and psychometric properties of these knowledge assessment instruments should be acceptable for diabetic knowledge evaluation and instruction.

Evaluation of a weekend group for parents of children with diabetes

A weekend group was organized for parents of children with diabetes with the aim of teaching them an approach to identifying and tackling common problems. A total of 97 parents of 85 children participated. The effectiveness of the weekend was evaluated and measures were taken before, immediately following and 3 months afterwards. Parents rated themselves significantly more confident in looking after their child immediately following the weekend. although ratings of perceived difficulty in managing the child's diabetes did not alter. Three months later parents' confidence had further increased, although as before perceived difficulty was unchanged. The majority of parents reported making at least some changes either in daily management or other aspects of coping with their child's diabetes. Participation in such short-term groups represents an efficient approach to increasing the confidence of parents of children with a chronic illness.

A study of genetic linkage in schizophrenia

Families with more than one member affected by schizophrenia were identified and their members were interviewed. Four standardized diagnostic definitions (PSE, DSM-III, ICD-9, Feighner) were applied to all subjects who were classified as schizophrenic or not schizophrenic according to each definition. Non-schizophrenic psychiatric disorders which have been shown to be familially associated with schizophrenia were also identified. Twenty blood markers were ascertained for all subjects and evidence of co-segregation with schizophrenia was sought. No selective segregation was found and therefore there was no evidence suggesting linkage or supporting a monogenic theory of transmission of susceptibility to schizophrenia.

Platelet monoamine oxidase: specific activity and turnover number in schizophrenics and their families

Monoamine oxidase specific activities and molecular turnover numbers have been measured in families with at least two schizophrenic members. Neither measure of monoamine oxidase was different in schizophrenics compared with their first degree relatives. Molecular turnover number was remarkably similar in males and females and when the group was considered by age, diagnosis, drug status and family membership. Neither specific activity nor turnover number could be used in risk estimation for the development of schizophrenia in members of these families.

Mesangial proliferative glomerulonephritis associated with multiple myeloma

IgA lambda multiple myeloma was diagnosed in a 58-year-old white woman after the onset of nephrotic syndrome. Serial renal histology demonstrated progressive mesangial proliferative glomerulonephritis. Electron microscopy revealed subepithelial electron dense deposits. Immunofluorescence microscopy demonstrated granular staining of peripheral capillary loops with IgG and C3. No IgA was present. No evidence of deposition of the myeloma protein in the glomeruli was found. The temporal relationship of occurrence of the two diseases and the progression of glomerular disease suggest that multiple myeloma be added to the list of malignancies causing immune complex glomerulonephritis.

NH4Cl inhibition of transport in the rabbit cortical collecting tubule

Ammonium has previously been found to inhibit transport in a number of tissues. The present experiments were designed to evaluate the effect of ammonium chloride on transepithelial voltage (VTE) and cation transport in the isolated rabbit cortical collecting tubule perfused in vitro. Peritubular NH4Cl (2-10 mM) inhibited VTE in these tubules independent of bath or lumen pH. Luminal NH4Cl had a similar effect. However, VTE did not change with bath NH4Cl in tubules treated with amiloride or ouabain. Furthermore, when bath PCO2 was lowered simultaneously with the addition of NH4Cl to the bath, little change in VTE occurred, raising the possibility that intracellular pH falls after addition of NH4Cl to the bath. Consistent with the voltage effects, 5 mM NH4Cl in the bathing solution inhibited net sodium reabsorption by 36% and potassium secretion by 44%. Unidirectional lumen-to-bath tracer fluxes were consistent with predominant inhibition of the sodium reabsorptive flux and the potassium secretory flux. These findings may have relevance to metabolic acidosis in vivo because ionic ammonium concentrations attain the levels used in this study.

Transport of ammonia in the rabbit cortical collecting tubule

Nonionic diffusion and diffusion equilibrium of ammonia have been generally accepted as the mechanism of urinary ammonium excretion. However, these characteristics have not been examined directly in vitro. In the present studies, nonionic diffusion and diffusion equilibrium of ammonia were examined in rabbit cortical collecting tubules perfused in vitro. Collected fluid ammonium and pH were measured in tubules exposed to chemical gradients of NH3/NH+4. In tubules perfused with an acid perfusate free of ammonia and bathed with solutions containing NH4Cl, collected fluid ammonia failed to equilibrate across the epithelium except at slow flow rates. The estimated apparent permeability coefficient to NH3 was approximately 5 X 10(-3) cm/s. Predominant nonionic diffusion of NH3, rather than transport of NH+4, was indicated by alkalinization of luminal fluid in tubules exposed to peritubular NH4Cl and by the relative influence of peritubular NH+4 and NH3 on ammonia entry. In tubules perfused with an acid solution containing NH4Cl, little loss of ammonium was detectable, indicating a low permeability to NH+4. In contrast to the restricted diffusion of NH3 in cortical collecting tubules, proximal convoluted tubules exhibited a much higher apparent permeability to NH3. In conclusion, nonionic diffusion of NH3 accounted for most ammonium transport in the proximal convoluted tubule and in the cortical collecting tubule. However, there was relatively restricted diffusion in the collecting tubules; this may account for the failure of whole kidney ammonium excretion to obey quantitatively the predictions of nonionic diffusion and diffusion equilibrium of ammonia.

Short-term group therapy for stroke patients in a rehabilitation centre

Three groups of eight patients who had suffered strokes participated in short-term group therapy run by a psychiatrist and a social worker. A simple assessment was made by patients and therapists, further information being obtained by means of a follow-up questionnaire. The feasibility of this approach, and the indications that such groups might be beneficial, are discussed. Certain common themes emerged from all three groups, but it was interesting to note a different reaction was shown by men and women in response to their strokes. The provision of such groups for patients suffering from different illnesses and alternative ways of running these groups are suggested.