Systematic search for 1 alpha,25-dihydroxy-vitamin D3 receptors in human breast carcinomas.

We looked systematically for the presence of receptor like binding sites for 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) in the cytosol from 22 breast cancers. Cytosols were centrifuged on 5-20% sucrose gradients after labeling with tritiated 1,25 (OH)2D3 (3H-1,25(OH)2D3 or 25-hydroxyvitamin D3 (25(OH)D3 alone or in the presence of a large excess of these unlabeled sterols. Binding sites for 1,25 (OH)2D3 migrating in the 3.

Development of electrical membrane properties in cultured avian neural crest.

In previous studies of the development of membrane excitability in vertebrate neurones, a calcium current has commonly been observed first, later replaced by a sodium current. We have now examined the development of membrane currents in explant cultures of mesencephalic neural crest cells from the quail embryo. Some of these cells constitute the precursors for the ciliary and trigeminal ganglia and in certain conditions can be characterized morphologically as neurones after only a few hours in culture.

Membrane currents in a developing parasympathetic ganglion.

It is reported that chick embryo ciliary ganglion neurons that have just terminated their migration and are in the process of forming a ganglion express several properties underlying membrane excitability. Evidence is presented which suggests that these cells possess voltage-dependent sodium, potassium, and calcium currents as well as a calcium-activated potassium current. These currents resemble those previously described in the more mature ciliary ganglion (Bader, C.

Cellular utilization of cytosolic NADPH in kidney and liver cells from rats fed a normal or a vitamin D-deficient diet.

The amount of reducing equivalents from NADPH generated by glucose 6-phosphate dehydrogenase activity (G6PD) used in mixed function oxidation (pathway I) or in reductive biosynthesis (pathway II) has been determined by cytochemical methods and microdensitometry in cells from the pars recta (PR) and distal convoluted tubule (DCT) of the kidney and from centrilobular (CL) and periportal (PP) hepatocytes from rats fed a normal or a vitamin D-deficient diet. In the kidney, pathway I activity was similar to that of pathway II in PR, whereas in DCT pathway II was markedly predominant. Feeding a vitamin D-deficient diet resulted in an increase in the total amount of reducing equivalents in PR and DCT.

Voltage-activated and calcium-activated currents studied in solitary rod inner segments from the salamander retina.

1. Solitary rod inner segments were obtained by enzymatic dissociation of the tiger salamander (Ambystoma tigrinum) retina. Their membrane currents were studied with the single-pipette voltage-clamp technique.

Effects of weight and glucose ingestion on urinary calcium and phosphate excretion: implications for calcium urolithiasis.

Renal handling of phosphate and calcium was studied in 17 hypercalciuric stone-formers, 6 normocalciuric stone-formers and 10 normal subjects before (fasting state) and 45 and 75 min after the ingestion of 100 g glucose. The ratio of fasting urinary calcium to creatinine (UCa/creat) was higher in hypercalciuric than in normocalciuric stone-formers or controls. A positive correlation was found between weight index and fasting UCa/creat for all subjects studied (r = 0.

Diffuse and local effects of light adaptation in photoreceptors of the honey bee drone.

Intracellular recordings from drone photoreceptors were made by means of glass microelectrodes in superfused retinae. Exposure of a small portion of a cell to white light decreased the amplitude of responses to a small stimulus subsequently applied at different sites of the photoreceptor cell, i.e.

[Vitamin D metabolites in a new case of drug-induced hypercalcemia (author's transl)].

The authors report on a new case of severe hypercalcaemia induced by prolonged oral treatment with high doses of vitamin D2. (6 mg/day for 9 months). Blood calcium level did not return to normal until 6 months after the drug was discontinued.

[Measurement of plasma 1,25 dihydrovitamin D. Normal and pathological values in adults (author's transl)].

Plasma levels of 1,25 dihydrovitamin D (1,25 (OH)2D) were measured in normal subjects and in patients with various diseases, using a radiocompetition method. Mean values of 89 +/- 58 pmol/l (1 s.d.

Storage and retrieval of bibliographic references using a microprocessor system.

A program is described for the storage and retrieval of bibliographic references. The program, designed for a dual floppy disk microcomputer system, allows fast access to references, which can be retrieved by keywords, by authors' names or by string matching. Provided a printer is available, the program prints reprint requests, while new references are being stored, and prints hard copies of the references.

[Evidence for a glucose-dependent renal phosphorus leak in normo- and hypercalciuric stone-formers (author's transl)].

Changes in phosphatemia and in maximum renal threshold phosphate concentration (TmP/GFR) have been measured before and 45 and 75 min after oral ingestion of 75 g of glucose in 10 hypercalciuric lithiasic patients (HCI), 8 normocalciuric lithiasic patients (NCI) and 7 control subjects. After glucose ingestion, whereas plasma phosphorus decreased in all 3 groups, TmP/GFR decreased significantly in HCI and NCI but not in controls. A slight increase in calcium excretion was noted in the subjects with HCI and NCI after glucose load.

A voltage-clamp study of the light response in solitary rods of the tiger salamander.

1. Single, isolated, rod photoreceptors were obtained by enzymatic dissociation of the tiger salamander (Ambystoma tigrinum) retina. These solitary cells retained the morphological features of rods of the intact retina and could be maintained in culture for several days.

Ineffectiveness of topical adenine arabinoside 5'-monophosphate in the treatment of recurrent herpes simplex labialis.

The ability of topical 10 per cent adenine arabinoside 5'-monophosphate to decrease the severity and frequency of recurrent herpes simplex labialis was evaluated in a double-blind, randomized study of 233 patients at three collaborating institutions. Nine clinical and four virologic measurements were used to evaluate drug efficacy during a single episode. No statistically significant improvement in any measurement was seen in the drug-treated patients.

The natural history of recurrent facial-oral infection with herpes simplex virus.

Fifty-seven episodes of facial-oral infections with herpes simplex virus (HSV) (cold sores) were studied in 41 ambulatory patients. Patients were examined within 24 hr of the onset of symptoms and for five consecutive days. Clinical parameters were assessed, lesion size was measured, and daily cultures for virus were performed.

[Rubella vaccination during puerperium? Effect of rubella vaccination during puerperium on the titer of HAH].

The rubella-HI-titer of 142 women vaccinated against rubella during childbed and 126 women not vaccinated during childbed were tested at the time of delivery and again 10-12 weeks later. The results show booster effects if prevaccinal titer were low. In the case of higher prevaccinal titer a titer reduction due to vaccination results.

Responses to light of solitary rod photoreceptors isolated from tiger salamander retina.

Single, isolated rod photoreceptors were obtained by enzymatic dissociation of the tiger salamander (Ambystoma tigrinum) retina. These solitary cells retained the morphological features of rods of the intact retina and could be maintained in culture for several days. When impaled with micropipettes for electrophysiological recording, dark-adapted solitary rods had during darkness a resting potential of approximately -45 mV and a steady-state slope resistance of 500 Momega at rest.