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Fecal fat, bile acid, and neutral sterol excretion and biliary bile acid, phospholipid, and cholesterol were studied in 36 patients 6 to 12 months after jejunoileostomy for obesity. No relationship was observed between the degree of steatorrhea and weight loss, although fecal fat rose sharply in all except 2 patients. Mean neutral sterol excretion in feces was unchanged after operation except in cholecystectomized patients. No relationship could be demonstrated between serum cholesterol decrease and fecal biel acid, which rose 3-fold, or between cholesterol and the sum of fecal fat and neutral sterol. Fecal excretion of cholic and deoxycholic acid together increased more than the total excretion of cxcretion patterns were demonstrable: moderate fecal fat (24 g or less on 65-g intake) was associated with a predominance of secondary bile acids in feces and in bile; high fecal fat (above 24 g/day) was associated with predominantly primary bile acids. A high incidence of gallstones or previous cholecystectomy (36%) was found preoperatively and of 25 patients with normal cholecystograms, four developed stones and five had nonvisualization of gallbladder 6 to 12 months postoperatively. Bile saturation ratio and lithogenic index were not consistently changed postoperatively. No clear cut increase in lithogenic potential or in bile acid (lithocholic acid) hepatotoxic potential after jejunoileostomy was demonstrable.

The optical transmitance, crystallographic structure and dielectric properties for PLZT 8/65/35 samples either containing a number of various dopands (Mn, Fe, Co, Eu), or subject to neutron or electron irradiation have been studied.

Pyroelectric and dielectric properties and switching of ferroelectric PLZT ceramics have been studied in the range 290–470 K. The effect of γ-irradiation on pyroelectric coefficient, dielectric permittivity and rate of Barkhausen jumps sequence at polarization switching of PLZT ceramics is found to be most pronounced at phase transition.

Casa Pangue glacier is a regenerated valley glacier, covered by supraglacial moraine of variable thickness (1 to 3 m). Seven moraine in-transit arcs have originated from avalanches falling on the ice from the steep walls at the head of the valley. The debris has been relocated by glacier movement, and vegetation has become established on areas with sediment cover. Primitive soil has developed very rapidly, probably in less than 100 a. Chemical analysis of soil samples show that it is acid (pH 4.6 to 4.7), nitrogen and organic matter are absent, calcium content is low, and potassium content is high. Pedogenic processes are mostly related to intense chemical weathering, under conditions of more than 4 000 mm a−l of total precipitation.The plant communities established on the moraine are essentially similar to the Va1divian rain forest that characterizes the region. The most frequent tree is “coihue” (Nothofagus dombeyi), followed by “teniú“ (Weinmannia trichosperma) and “notro” (Embothrium coccineum). One specimen of N.dombeyi was found to be 18 m tall and 0.62 m in diameter; many others were taller than 12 m and reproduction was abundant. Dendrochronological analysis indicates a minimum age of 45 a for the oldest tree. Other plants found here are shrubs, some hemiparasitic and creeping plants, mosses, lichens, ferns, and fungi.Using air photographs of 1942, 1953, 1970, and our own oblique photographs of 1978, taken from the summit of a neighbouring peak 1 200 m above the glacier tongue, average surface velocity of the glacier tongue was estimated at 22.5 m a−l for the lower and intermediate sectors where the trees are growing. If the total length of the regenerated valley glacier is taken into account, the mean annual movement rate is 35.0 m a−l. If this value is extrapolated over the last 45 a, the trees have moved an average distance of at least 1 000 m in that time.The discovery of established communities (also observed at Río Blanco glacier, southwest of Mt Tronador) on moving ice constitutes an event not previously recorded in glaciological literature. Some significant aspects are discussed: time lapse for soil development on moraine deposits, primary plant succession on moraine deposits, the need of stable ground for plant colonization, the absolute validity of radiocarbon dating of glacier advances using fossil wood found within terminal moraines, and the validity of lichenometric techniques in deglaciated terrain.

PLZT and PSN transparent ferroelectric ceramics have been subjected to γ-irradiation (energy ≈ 1;15 MeV; power of the dose 1050 r/s; doses up to 3 × 109 rad), electron irradiation (energy ≈ 4.5 MeV; power of the dose ≈ 1012 electr./cm2 · s: doses up to 1018 electr./cm2) and direct irradiation in a thermal reactor channel (neutron energy ≥ 0.1 MeV; flow density from 1.8 × 1011 to 2.4 × 1012 n/cm2 s: the dose up to 1018 n/cm2).Results of complex X-ray, dielectric, and optical studies of the irradiated ceramics are interpreted in terms of radiation-induced defect interaction with the real structure defects of the initial material taking into account the chemical and phase constitution, as well as the defectness and ordering of structural elements at different levels of the latter.

PLZT and PSN ceramics have been exposed to γ-radiation (energy ≈ 1.15 MeV, dose up to 3 · 109 rad), electron flux (≈4.5 MeV, dose up to 3.1018 electr./cm2) and fast neutrons (≥ 0.1 MeV, dose up to 1018 n/cm2). The irradiated material was used to study radiation effects on dielectric parameters (e and tgδ were measured at frequencies from 1 kHz to 5 MHz), polarization (dielectric hysteresis quasistatic loops) and non-linear optical properties (I2w). The measurements were made in the region of phase transition as well as to examine annealing of radiation-induced defects. As compared to PLZT the PSN ceramics is more resistant to radiation, the most sensitive PLZT compounds being with 7 ≤ × ≤ 9.5 at .% of La. Obtained results are explained by the change of ion charge, redistribution of vacancies in A and B sublattices of PLZT and by possible ion ordering in sublattice B of PSN with account for intrinsic fields in the relevant compounds.

Mean and peak jejunal bile salt concentrations during digestion of a standard fat meal were found to be significantly lower in six Puerto Rican patients with untreated tropical sprue, all of whom had steatorrhoea, than in six asymptomatic subjects who had normal fat absorption. Bile salt pool size and turnover time did not differ significantly in the two groups. It is suggested that bile salt concentrations may be reduced in the proximal small intestine of patients with tropical sprue as a result of excessive dilution by intestinal fluid. The finding of low bile salt concentrations in two asymptomatic subjects indicates that bile salt lack alone may not be sufficient to produce steatorrhoea.

From these data, it can be said that the metabolism of carbohydrates and proteins is deranged in patients with the history of sterility and repeated abortions or congenital malformations. In these cases, all other conditions which could account for sterility or abortion were found to be in order. The abnormal histochemical changes, the alterations in the Krebs citric acid cycle, the decreased secretion of glucose-6-phosphatase and alkaline phosphatase together with the inability of the tissue to synthesize amino acids to RNA and DNA and hence on to the various enzymes needed in the carbohydrate metabolism probably indicate that the endometrial tissue in these patients was not carrying on the process of glycolysis or glycogenesis in a satisfactory manner. This may be due to (1) lack of estrogen and progesterone due to pituitary or ovarian failure, (2) anatomic, structural, and physiologic abnormality of the uterus and/or endometrium, (3) poor blood supply due to capillary disease, (4) a combination of all three factors. Any one of these factors may affect the amount of glucose and oxygen delivered to this tissue. In some instances these abnormal changes can be corrected by the proper use of the ovarian steroids.

A twenty-two year old man with recurrent stiffness following exercise was found to have chemical and histologic changes consistent with partial deficiency of myopnosphorylase. Muscle biopsy showed increased glycogen and a decrease in glycogen phosphorylase. Ischemic muscle exercise yielded a subnormal increase in venous lactate which was returned toward normal by prior administration of oral fructose or parenteral glucagon but not by oral glucose. Oral alcohol also increased blood lactate but did not enhance potassium uptake. A review of twenty-four reported cases of McArdle's disease revealed previously unrecognized major characteristics of this abnormality, including the predominance of exercise intolerance as an early symptom, the occurrence of muscle cramps before age eighteen in the majority of patients and the occurrence of myoglobinuria in approximately half the patients before the age of eighteen. These observations indicate that McArdle's disease is probably more common than suspected and exists in mild and unrecognized forms. Confirmation of the diagnosis is achieved by analyzing blood lactate levels after ischemic exercise and determining myophosphorylase content in muscle biopsy specimens.

ASPIRIN consumption is associated with gastric mucosal erosions1,2 and upper gastrointestinal haemorrhage3–5, and has been postulated as a factor in the development of chronic peptic ulcer6,7. It has been reported to cause chronic gastric ulcer in rats8. There is, however, no real understanding of the mechanism of these injuries. Menguy et al.9 suggested that the damage to the gastric mucosa results from lack of energy (ATP) for cell function. The reported antagonism of cholera enterotoxin by aspirin in the rat intestine10 might have been mediated through the inhibition of adenyl cyclase. We have now found, however, that aspirin can stimulate the activity of this enzyme in rat gastric mucosa.

Aspirin stimulated gastric mucosal adenyl cyclase activity in rats after oral administration. The stimulation became apparent within 5 min after an oral dose (300 mg/kg body wt). Aspirin was also shown to stimulate adenyl cyclase activity when added to gastric mucosal homogenate in vitro and some correlation was seen between the concentration of aspirin used and adenyl cyclase activity.

Squamous cell cancer was induced in the uterine cervix of S-3H strain of mice within 8 to 12 weeks after implantation. The experiments compared the metabolism of carbohydrates and nucleic acids in the cervical cancer with normal cervical tissue. It determined the effect of cancer growth upon the carbohydrate and nucleic acid metabolism of other essential organs by measuring the following enzymes and metabolites. Lactic acid content, glycogen, glycogen synthetase, glucose-6-phosphate dehydrogenase, and TPN-dependent isocitric dehydrogenase. These substances were significantly altered in the spleen, kidney, and cervical cancer of the cancer animals. The relative rate of mitosis in all structures was evaluated by assaying the tritiated thymidine at various time intervals after intraperitoneal injection. The DNA and RNA content was estimated in all by the quantitative extraction of the nucleic acid fraction. Marked changes in the metabolic rate and nucleic acid metabolism was noted in the spleen, kidney, lymph nodes, and cervical cancer.