The continuing risk of vitamin-D intoxication

Eight cases of vitamin-D poisoning are described. In six patients this therapy was unnecessary and in the remaining two patients inadequate supervision of the treatment resulted in overdosage. In five cases the history of vitamin-D therapy was either unknown or not appreciated by the referring clinician so that three surgical procedures of dubious value were performed on two patients. Large doses of vitamin D should only be used when strictly indicated and on the understanding that close biochemical and clinical supervision is necessary.

The natural history of a non-stenotic bicuspid aortic valve

Forty-one patients in whom the diagnosis of a non-stenotic bicuspid aortic valve had been established by noninvasive techniques were followed up for a mean of 10.9 years. During this period, 2 patients required aortic valve replacement because of the development of calcific aortic valve stenosis at the ages of 52 and 64 and 5 others developed evidence of mild aortic valve stenosis. The appearance of calcium in a bicuspid aortic valve suggests the possibility of subsequent calcific aortic stenosis, and patients with this feature should be carefully followed up. Bacterial endocarditis on the aortic valve occurred in 3 patients, one of whom developed severe aortic regurgitation and subsequently died. Patients with a bicuspid aortic valve are at definite risk from bacterial endocarditis and should receive appropriate antibiotic prophylaxis. In 26/41 (63%) patients there was no clinical change during the follow-up period, including 7 of the patients over the age of 50.

Lysosomal enzymes in human urine: evidence for polymorphonuclear leucocyte proteinase involvement in the pathogenesis of human glomerulonephritis

1. Lysosomal proteinase activity was assayed in human cadaver kidney, urine, granules from polymorphonuclear leucocytes of normal persons, and urine samples from 154 patients with renal disease.

2. Granules from polymorphonuclear leucocytes showed proteinase activity at acid and neutral pH, whereas cadaver kidney showed proteinase activity at acid pH only.

3. The urine from 13 patients with glomerulonephritis showed proteinase activity at both acid and neutral pH as well as increased amounts of antigenic glomerular basement membrane fragments. The properties of the urinary proteinases suggested that they had originated in polymorphonuclear leucocytes.

4. Only the urine samples containing these proteinases were capable of degrading isolated human glomerular basement membrane in vitro.

5. Clinical recovery, where it occurred, was accompanied by the disappearance of urinary proteinase activity, and reduction in glomerular basement membrane antigen excretion.

Effect of BCG on alloimmune cell-mediated cytotoxicity in (C57BL/6Jfemale x A/Jmale)F1 mice. II. Correlation with BCG activity in syngeneic tumor systems

The effectiveness of selected BCG regimens to produce an activation of cell-mediated cytotoxicity (CMC) in an allogeneic tumor system was compared with its ability to cause tumor regression in syngeneic tumor systems. In the tumor system selected in both inbred LEW rats and inbred C57BL/6J and (C57BL/6Jfemale x A/Jmale)F1 mice, a correlation was observed in that BCG treatments that caused marked CMC activation in the allogeneic tumor systems also effectively caused tumor regression and increased animal survival in syngeneic systems. It was concluded that the allogeneic CMC reaction can be used to predict the capacity of BCG to cause tumor rejection.

Effect of BCG on alloimmune cell-mediated cytotoxicity in (C57BL/6Jfemale x A/Jmale)F1 mice. I. Effect of different BCG treatments on cytotoxicity mediated by T-cells and macrophages

The effect of BCG on the development of cell-mediated cytotoxicity (CMC) in the spleens of allogeneic tumor-bearing female (C57BL/6Jfemale x A/Jmale)F1 mice was studied. BCG-treated tumor-bearing animals elicited a stronger CMC response than did the untreated tumor-bearing animals. Furthermore, the degree of activation was dependent on the time, route of injection, and dose of BCG. Therefore, if the BCG was administered at suboptimal conditions, a less marked stimulation of the CMC resulted. A combination of a high BCG dose given iv 12 days before implant of P815 tumor cells and a low, second dose given at the time of implant produced the most marked activation of the CMC response. By the use of in vitro technique, the specific CMC was mediated mostly by T-cells, with macrophages making a less significant contribution.

The binding of lipopolysaccharide from Escherichia coli to mammalian cell membranes and its effect on liposomes

The kinetics of the absorption of 32P- or 14C-labelled lipopolysaccharide from Escherichia coli NCTC 8623, serotype 0 125, chemotype XII, to erythrocytes, leukocytes, peritoneal macrophages and peritoneal lymphocytes was examined. Under variable conditions maximal levels of binding were found due to saturation of receptor sites on the cell membrane or steric hindrance by bound lipopolysaccharide. During adsorption slight leakage of haemoglobin was found but complete lysis of erythrocytes was ruled out after noting the effect of lipopolysaccharide on artificial lipid bilayers. The affinit of lipopolysaccharide to cell membranes revealed a consistent pattern of cyclic fluctuation between adsorption and desorption. A model was proposed to explain this cyclic fluctuation in binding based on membrane reorganization. It was significant that the cycle of lipopolysaccharide adsorption-desorption proceeded to completion even if the process was interrupted. The indication was that, once triggered, membrane reorganization occurred independently without influence from the test environment.

The degradation of human glomerular basement membrane with purified lysosomal proteinases: evidence for the pathogenic role of the polymorphonuclear leucocyte in glomerulonephritis

1. Human polymorphonuclear leucocyte elastase and cathepsin G were incubated with preparations of isolated human glomerular basement membrane at neutral pH and 37 degrees C. 2. The ability of these enzymes to degrade glomerular basement membrane was followed by the release of hydroxyproline. Both proteinases released considerable amounts of hydroxyproline. 3. By using Sephadex G-100 it was shown that the solubilized basement membrane fragments appeared as a single peak and had a molecular weight of over 100 000. These proteins after reduction were analysed by sodium dodecyl sulphate-gel electrophoresis to examine their subunit pattern and determine their molecular size. 4. The released basement membrane proteins gave at least four precipitin lines with a rabbit anti-(glomerular basement membrane) antiserum. 5. These results support the concept that polymorphonuclear leucocyte neutral proteinases play an important role in the pathogenesis of glomerulonephritis. 6. At acid pH values cathepsin B also released hydroxyproline from human glomerular basement membrane but the lysosomal carboxyl proteinase, cathepsin D, had no action.

The binding of adjuvant-active mycobacterial peptidoglycolipids and glycopeptides to mammalian membranes and their effect on artificial lipid bilayers

The nature of the binding of adjuvant-active amphiphilic mycobacterial peptidoglycolipids and glycopeptides to mammalian plasma membranes was investigated together with their effect on the stability of artificial lipid bilayers. The importance of these interactions between mycobacterial components and membranes is discussed in relation to immunopotentiation, mitogenicity and tuberculous infection.

Vitamin D metabolism and the response to 1,25-dihydroxycholecalciferol in Osteoporosis

The metabolism of isotopically-labelled cholecalciferol and the response to small doses of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) was studied in a group of women with osteoporosis presenting with crush vertebral fracture. No abnormality of vitamin D metabolism was detected. The administration of 1 microgram 1,25-(OH)2D3 for between 8 and 20 days was associated with an increased intestinal absorption and urinary excretion of calcium but caused no improvement in calcium balance. There was a small but significant rise in serum calcium and phosphorus and significant reduction in immunoassayable parathyroid hormone levels during treatment. It is concluded that 1,25-(OH)2D3 is unlikely to be of value in the management of osteoporosis.

Treatment of fulminant hepatic failure by polyacrylonitrile-membrane haemodialysis

24 patients with fulminant hepatic failure who had deteriorated to grade-IV coma were treated by repeated periods of haemodialysis with a polyacrylonitrile membrane. 9 patients fully recovered consciousness, and 8 (33%) survived to leave hospitals. These results are to be compared with those of conservative management alone (15% survival in 53 cases) and those obtained initially with charcoal haemo-perfusion (38%). Of the 16 treatment failures, cerebral oedema was found at necropsy in 13 (18%). Whether this would have been less of problem if treatment had been started earlier in the course of the illness remains to be determined.

Effect of different doses of BCG on an allogeneic cell-mediated antitumor response in mice

The effect of BCG on the development of cell-mediated cytotoxicity (CMC) in the spleens of allogeneic tumor-bearing (C57BL/6 X A)F1 mice was studied. BCG-treated tumor-bearing animals elicited a stronger CMC response than did the untreated tumor-bearing animals. Furthermore, the degree of activation was dependent on different doses of BCG, so that if the BCG was administered at doses above or below the optimum dose, a less marked stimulation of the CMC resulted. The combination of BCG given before the tumor implant plus an intratumor inoculation resulted in a significantly higher CMC than did either treatment alone.

Paravertebral and peripheral ligamentous ossification: an unusual association of hypoparathyroidism

A 62-year-old man with idiopathic hypoparathyroidism and extensive paravertebral and ligamentous ossification is reported. The clinical and radiological findings of this, and other reported cases, are discussed and compared with other causes of paravertebral ossification.

An outbreak of infection caused by a gentamicin-resistant Staphylococcus aureus

An outbreak of infection caused by a strain of Staphylococcus aureus resistant to gentamicin and tobramycin and other antibiotics occurred in two wards in a hospital. Eight patients were colonized, of whom six had clinical infections. Previous administration of gentamicin appeared to predispose the patients to infection with the strain. Restriction of the use of gentamicin and tobramycin is essential to preserve their value in serious infections.

1,25-dihydroxycholecalciferol in hypoparathyroidism

8 patients with hypoparathyroidism have been treated successfully with 1,25-dihydroxycholecalciferol (0-25-1-0 mug/day) for 4-24 mo. Normal serum-calcium levels were restored in all patients, but half the patients required supplementary oral calcium. Treatment reduced serum-phosphorus in all patients, but values remained high in 3, and the renal-tubular reabsorption of phosphate returned to normal in only 2 of the 8 patients. A comparison is made with the effects of oral therapy with massive amounts of calcium salts. The data obtained are discussed in relation to the probable mode of therapeutic action of 1,25-dihydroxycholecalciferol.

Biosynthesis of methylmercury compounds by the intestinal flora of the rat

The contents of the rat cecum and, to a lesser extent, those of the small intestine, synthesized methylmercury from mercuric chloride labeled with Hg 203 in vitro under aerobic or anaerobic conditions. The rate of formation was approximately 18 ng/g cecal contents/20 hr. The synthesis of methylmercury was inhibited by antibiotics and by filtration of the cecal contents through membrane filters, indicating that the bacterial flora of the gut participates in the reaction. Pure cultures of bacteria, isolated from the intestinal tract of the rat, could methylate mercuric chloride. It was estimated that the total amount of methylmercury synthesized from ingested inorganic mercury in man in approximately 400 ng/day.

Studies on the effect of salicylic acid on normal skin

This investigation was prompted by our ignorance of the way in which salicyclic acid aids desquamation. Salicyclic acid in aqueous cream or white soft paraffin and in concentrations of 2-12% was applied to normal skin of twenty-three subjects while the vehicle alone was applied to the contralateral sites. Biopsies and skin surface biopsies were taken from the test and control sites after 1 week. Histological examination showed that there was less horny layer on the test specimens but that there were no qualitative or quantitative differences in the structure of the viable epidermis. Portions of the biopsies were incubated in the presence of tritiated precursor compounds and subsequent autoradiographic examination showed no difference in the incorporation of thymidine, cytidine or histidine between test and control preparations. Scanning electron microscopy of skin surface biopsies showed some changes in all specimens--presumably due to hydration--but also showed striking differences between test and control sites and were especially marked with higher concentrations of salicylic acid. It is suggested that salicylic acid causes desquamation by dissolution of intercellular cement material.

Metabolic fate of administered 1,25-dihydroxycholecalciferol in controls and in patients with hypoparathyroidism

In four healthy controls and three patients with hypoparathyroidism serum-1,25-dihydroxycholecalciferol (1,25-D.H.C.C.) concentrations, after oral or intravenous administration, declined biphasically with a rapid-phase half-time of about 14 hours. Repeated oral doses of 1 mug 1,25-D.H.C.C. (2-4 nmol) produced serum concentrations well below the assayed normal range but were nevertheless effective in raising serum-calcium. It is suggested that orally administered 1,25-D.H.C.C. acts directly on the intestinal mucosal-cell nucleus to promote calcium absorption. 1,25-D.H.C.C. is more rapidly eliminated from the body than vitamin D, and it is predicted that any hypercalcaemia caused by 1,25-D.H.C.C. therapy should be of relatively short duration.

How many tastes are there for low concentration "sweet" and "sour" stimuli? - Threshold implications

Ascending series of solutions of sucrose, glucose, and citric acid were tasted and detection and recognition thresholds were noted; subjects were also required to determine the number of taste sensations that occurred and their sequence of occurrence. It was found that subjects varied in their reports of the number of taste changes and hence potential criteria for detection and recognition. Even among those subjects who reported the same number of criteria there was little consistency as to which were actually chosen for detection and recognition. Some subjects even used an intensity change rather than a quality change to signal a threshold. They criterion can thus be seen to be a potential variable in threshold measurement, and criterion-free measures of sensitivity are recommended. Taste quality descriptions were also studied and a high proportion of novel descriptions was noted; it was hypothesised that this was due to the fact that subjects were not primed with traditional descriptive terms during the instructions.

Behavioral and social effects of heroin self-administration and withdrawal

Behavioral and social reactions to intravenously administered heroin were studied during a 33-day experimental addiction cycle. Three groups of four subject volunteers were allowed to self-administer heroin for a ten-day period as part of a longer study of oplate antagonists. Data relevant to sleep patterns, energy expenditure, social interaction, and other observable behaviors were collected during hourly observations. Comparison of behavioral differences before and after drug administration indicated few significant acute reactions. Reactions to long-term heroin self-administration were most pronounced in the areas of sleep behavior and social interaction. Subjects tended to sleep less, especially during the initial period of acquisition, and to withdraw more from social contact. No changes were noted in energy expenditure during waking hours. The results were interpreted in terms of physiological tolerance, central nervous system arousal, and sleep deprivation.

Treatment of hypoparathyroidism with 1,25-dihydroxycholecalciferol

Five patients with hypoparathyroidism (three post thyroidectomy and two idiopathic) were treated with synthetic 1,25-dihydroxycholecalciferol (1,25-(OH)2-D3) for up to 6 months. In each case daily oral administration of 1 microgram 1,25-(OH)2-D3, either alone or with additional calcium, raised ther serum calcium into the normal range. The serum phosphorus and the renal tubular reabsorption of phosphorus fell during treatment. None of these patients developed hypercalcaemia and no other complications of treatment have been recorded. 1,25-(OH)2D3 seems to represent a significant improvement over conventional methods for treating hypoparathyroidism.

Interpersonal behavior in a small group setting during the heroin addiction cycle

In a study of social interaction during an experimental addiction cycle, male narcotic addicts expressed more hostility after higher doses of heroin. No consistent role variations were observed in dominance, friendliness, or therapeutic-orientation.

Interactions of carbenicillin and ticarcillin with gentamicin

The in vitro inactivation of gentamicin by carbenicillin and a new semisynthetic penicillin, ticarcillin (BRL 2288), has been demonstrated. Gentamicin half-lives have been studied in eight patients with end-stage renal failure, and a 25 to 74% reduction in half-life has resulted from the concomitant administration of therapeutic doses of carbenicillin and ticarcillin.

Influence of the length of Heineke-Mikulicz pyloroplasty on the area of gastric outlet

Using agar casts of human post-mortem stomachs we have shown that (1) A 4-cm Heineke-Mikulicz (H-M) pyloroplasty increases the diameter of the narrowest area of the pylorus in every case. (2) Further increase to an 8-cm pyloroplasty leads to a further comparable increase in the size of the outlet. (3) The distortion caused by H-M pyloroplasty does not reduce the mean cross-sectioned area of the pyloric canal. (4) The narrowest area of the outlet appears to remain at the pylorus. These findings and their significance in gastric emptying are briefly discussed.

Simplified repair of abdominal aortic aneurysms using non-bifurcated (straight) inlay prostheses

The treatment of abdominal aortic aneurysms by prosthetic replacement is still attended by considerable hospital mortality, particularly when rupture has already occurred. We consider that the results could be significantly improved by the more widespread use of a simplified repair which consists of the insertion of a non-bifurcated (straight) tubular inlay prosthesis within the aneurysm. No attempt is made to resect or to transect the aorta and its bifurcation is preserved.

In a series of 61 consecutive patients, from which 4 were excluded because they died before definitive surgery, there were 30 intact and 27 ruptured aneurysms. The hospital mortality for prosthetic replacement of intact aneurysms was 15 per cent using bifurcation grafts in 20 patients and nil for straight prostheses in 10 patients. The respective figures for leaking aneurysms were 64 per cent in 14 patients and 38 per cent in 13 patients.

In our experience this simplified technique has resulted in diminished hospital mortality as a consequence of reduced operating times, blood loss and postoperative morbidity. It can, moreover, be universally employed except where gross separation of the origin of the common iliac vessels has occurred, which is uncommon, or in the rare instance of coexistent acute limb ischaemia.

The effect of triton WR-1339 on the subcellular distribution of trypan blue and 125 I-labelled albumin in rat liver

1. The density-gradient distribution patterns of acid phosphatase, Trypan Blue and denatured (125)I-labelled albumin were studied by discontinuous sucrose- and isopycnic sucrose-density-gradient centrifugation on combined heavy and light mitochondrial (M+L) fractions of liver isolated from normal rats and from rats injected with Triton WR-1339. 2. The results obtained from the subfractionation of the M+L pellet of normal animals indicate that the equilibrium density of Trypan Blue and acid-insoluble radioactivity is the same as that for acid phosphatase, which suggests they are bound by a common membrane to form a distinct subcellular population of lysosomal nature. 3. In contrast, the analysis of the isopycnic gradients obtained on subfractionation of M+L pellets of liver isolated from rats treated with Triton WR-1339 show that the acid-insoluble radioactivity has an equilibrium density around 1.21, whereas the acid hydrolases, including cathepsin D, show the characteristic shift to an equilibrium density of around 1.12. Trypan Blue is distributed along the gradient with distinct peaks at densities 1.22 and 1.12. 4. Similar equilibrium-density distribution patterns were obtained with M+L pellets isolated from rats pretreated with Triton WR-1339 but not injected with Trypan Blue. 5. Treatment of the rats with Triton WR-1339 does not affect albumin digestion of isolated intact lysosomes despite the fact that most of the cathepsin D and the albumin ingested by phagocytosis are located in different vacuoles. 6. It is concluded from these experiments that in the liver of animals treated with Triton WR-1339 (125)I-labelled albumin is located within heterophagosomes which do not fuse with heterolysosomes containing the non-ionic detergent Triton WR-1339. The inability of these two lysosomal populations to fuse is not due to Trypan Blue.