In vivo regulation of rat epididymal proteins by retinoids: analysis by two-dimensional electrophoresis.

The role of retinoids in the regulation of epididymal fluid protein expression was investigated. We compared the patterns of two-dimensional electrophoretic gels of proteins from luminal fluids, cytosols and spermatozoa (from control rats only) of control, retinoid-depleted, retinoid-depleted retinoic acid-complemented and retinoid-depleted testosterone-supplemented rats. This study compared the luminal fluid patterns from the 4 diets and observed 13 proteins whose expression was dependent on nutritional status. Eight were either absent or very weakly expressed in retinoid-depleted animals only, while their presence was obvious in control rats and in the retinoid-deficient retinoic acid- and testosterone-complemented groups. The expression of 8 proteins was greatly enhanced in retinoid-depleted testosterone-supplemented fluids as compared to control fluids. Five of the regulated proteins seemed to be captured by spermatozoa as they were observed in sperm protein patterns of control rats. These results clearly show that the synthesis of several epididymal proteins is influenced by retinoids. Since testosterone-supplemented animals on retinoid-free diet elicited the same response as retinol and retinoic acid ones, testosterone is likely to be the mediator of retinoid action on epididymal protein synthesis. Nevertheless, the observation of one protein whose expression is stimulated by retinoic acid only and is totally independent of testosterone also favors the direct influence of this retinoid.

Reconstitution of cytolytic alloreactivity with N-[4-[(4-fluorophenyl) sulfonyl]phenyl]acetamide (CL 259,763) in animals immunocompromised by cyclophosphamide.

A novel synthetic immunopotentiator, i.e. N-[4-[(4-fluorophenyl)sulfonyl]phenyl]acetamide (CL 259,763), was investigated for its potential in reconstituting the cell-mediated immune response of animals whose immunologic system had been severely depressed by cytoreductive agents. It was demonstrated that lymphocytes from mice which had received 300 mg/kg of cyclophosphamide (CY) immediately following antigen sensitization had a reduced capability of responding to alloantigens in mixed lymphocyte culture and failed to generate effective cytolytic T-lymphocytes (CTL) capable of destroying appropriate tumor target cells in a cytotoxicity assay. However, treatment of these immunocompromised animals with CL 259,763 produced a significant restoration of alloreactivity, as evidenced by an enhancement of the CTL response. Although effective doses of CL 259,763 ranged from 20 to 300 mg/kg, the optimal effect was observed at 75 mg/kg. Findings from a time course study indicated that the maximum restoration occurred when CL 259,763 was given to mice 2-5 days after, but not before or simultaneously with, CY treatment. Both the immunoimpairment by CY and its reversal by CL 259,763 appeared not to be antigen specific. The lessened immunoreactivity of CY-treated mice was explicable by the presence of suppressor cells in their spleens. These suppressors were able to adhere to plastic and resisted treatment with anti-Thy 1.2 antibody, indicating a macrophage characteristic. Flow cytometric analysis indicated a quantitative depletion of all T-lymphocytes, including Thy-1.2(+), Lyt-1(+), Lyt-2(+) and L3T4(+) subsets in the spleens of CY-treated mice; however, a population of Mac-1(+) cells was markedly expanded.(ABSTRACT TRUNCATED AT 250 WORDS)

Restoration of cytolytic T-lymphocyte response with a new immunopotentiator, N-(4-[(4-fluorophenyl)sulfonyl]phenyl)acetamide (CL 259, 763), in mice.

The immunorestorative characteristics of a novel synthetic immunomodulator, N-(4-[(4-fluorophenyl)sulfonyl]phenyl)acetamide (CL 259, 763), has been investigated in several experimental models. In one situation, the compound was shown to enhance the induction of a cytolytic T-lymphocyte response to the murine MBL-2 leukemia implanted in its syngeneic host in which only a minimal reactivity to the tumor is normally displayed. In a Vaccinia virus model, the compound similarly augmented the lytic activity of cytolytic T-lymphocyte to virus-infected targets in not only viral antigen-primed but also cyclosporin A-impaired mice. Likewise, the alloreactive cytolytic T-lymphocyte activity was recovered in animals immunocompromised by inoculation with murine plasmacytomas or cytoreductive anticancer drugs, such as cyclophosphamide and 5-fluorouracil. Thus, the present findings suggest that CL 259,763 is effective in potentiating the immune response to weak antigens as well as in restoring alloreactivity by sparing the immunotoxicity associated with the administration of cytotoxic drugs and the growth of neoplasms.

Effect of hyperthermia on the sensitivity of human colon carcinoma cells to mitoxantrone.

The effect of temperature on the cytotoxicity of mitoxantrone (MX) was investigated by exposing human WIDR colon carcinoma cells to elevated temperatures in the presence of drug. The survival of treated cells was determined by their ability to proliferate and to form colonies in vitro. It was demonstrated that incubation of WIDR cells with MX at 42 degrees C produced not only a higher toxicity but also a more rapid action than when cells were exposed to drug at 37 degrees C. By measuring the amounts of 3H-MX incorporated by treated tumor cells, it was shown that cells at 42 degrees C induced an approximately threefold increase in drug uptake when compared to cells at 37 degrees C. The effect seemed long-lasting but preheating did not induce tolerance to a subsequent exposure to MX hyperthermia. Therefore, it is clear that the cytotoxic potency of MX can be augmented by elevated temperature possibly by enhancing the uptake of drug. The present findings may prove useful for designing an effective clinical regimen of MX thermochemotherapy.

Effect of phosphate supplementation to breast fed very low birthweight infants on urinary calcium excretion, serum immunoreactive parathyroid hormone and plasma 1,25-dihydroxy-vitamin D concentration.

The effect of two doses of Phosphorus (P) supplementation to pooled breast milk (BM): 0.48 and 0.800 mmol/kg/24 h given during the second month of life was evaluated in 22 very low birthweight infants. The concentration of calcium and phosphorus in serum and urine, the serum concentration of immunoreactive parathyroid hormone (iPTH) and the plasma 1,25-dihydroxy-vitamin D concentration (1,25-OH-D) were compared to the values in 19 control infants. The mean +/- SD concentrations in control infants and adults are 63 +/- 18 microliters Eq/ml for serum iPTH and 85 +/- pmol/l for plasma 1,25-OH-D. With 0.48 P supplementation, urinary Ca (UCa) excretion (median and range) 0.238 mmol/kg/24 h (0.105-0.520) was lower than in the control group 0.288 (0.205-0.679) (p less than 0.05); the reduction of UCa was larger with 0.8 P supplementation: 0.047 (0.023-0.163) (p less than 0.01). P supplementation induced no change in serum Ca concentration but a slight and significant increase in serum iPTH was observed only with the 0.8 P supplementation: 55 microliters Eq/ml (less than 25-80) (p less than 0.05). With 0.8 P supplementation there was no significant change of plasma 1,25-OH-D concentration: 173 pmol/l (106-271) vs. 255 (132-293) in the control group. These data show that with 0.8 P supplementation, the hypercalciuria in BM-fed infant disappears without secondary hyperparathyroidism, but without any change in plasma 1,25-OH-D concentration.

[Plasma 25-OH D deficiency in Maghrebian children more than 10 years of age immigrated to France]. / Déficit plasmatique en 25 OH D chez les enfants maghrébins de plus de 10 ans immigrés en France.

From 1984 Feb 1st to April 30, 63 blood samples were collected from children more than 10 years old in the pediatric unit of CHR de St-Etienne, and analysed for 25 OH D, calcium, phosphate, magnesium and alkaline phosphatase serum concentrations. Mean 25 OH D is lower (22,6 nmol/1) in 26 migrant children (24 from Maghreb and 2 from Turkey) than in 37 European children (mean = 48,6 nmol/1; p less than 0,001). Serum concentration is under 10 nmol/1 in 3 of the 37 Europeans (8%), versus 13 of the 26 Maghrebians (50%). Mean alkaline phosphatase and phosphate are significantly higher in the 36 boys than in the 27 girls. A significative positive correlation is found between alkaline phosphatase and phosphate (r = 0,535; p less than 0,01). There is no relation between age, month of assessment, sex, height, weight, place of late holidays and any of the measured serum values.

Age-related changes in parathyroid hormone and 25 hydroxycholecalciferol levels.

Serum parathyroid hormone and 25 hydroxyvitamin D were measured in 124 normal subjects aged from 20 to 90 years. There was a significant progressive increase in serum parathyroid levels with age associated with a progressive decrease in total serum calcium. After the sixth decade there was a significant reduction of 25 hydroxyvitamin D serum levels. In each age group, there were no significant differences between men and women in all parameters measured. In normal elderly subjects there is an age-related decline of calcium absorption associated with reduced calcium intake and sun exposure leading to secondary hyperparathyroidism. These results emphasize the importance of calcium and vitamin D supplementation in elderly European population, not only in long-stay patients but in ambulatory normal people after 60 years.

[Levels of plasma 1,25-dihydroxyvitamin D and parameters of phospho-calcium metabolism in children with non-dialyzed chronic renal failure]. / Taux de 1,25-dihydroxyvitamine D plasmatique et paramètres du métabolisme phosphocalcique de l'enfant en insuffisance rénale chronique non dialysé.

1,25-diOH vitamin D, 25-OH vitamin D, parathyroid hormone, calcium and phosphorus were measured in the blood of 34 children and correlated. These children, 3 months to 17 years old, had chronic renal insufficiency of varying intensity. 15 of them were treated with vitamin D. We found a negative correlation between the 1,25-diOHD levels and the reduction of the clearance of inuline, serum creatinine and uremia. This suggests a defect in 1,25-diOHD synthesis appearing when the glomerular filtration rate is decreased by about 50%, except in the case of tubulopathies, where it appears earlier. In these children, the 1,25-diOHD levels correlated with calcemia, but not with phosphoremia. The high levels of PTH were related with the lowest levels of 1,25-diOHD. The regulation of calcemia is thus basically controlled by the renal possibilities. There was a positive correlation between 1,25-diOHD and 25OHD levels when GFR was lower than 0.6 ml/sec./1,73 m2, indicating a dependence of 1,25-diOHD levels or its substrate in severe chronic renal failure.

Activity of a novel anthracenyl bishydrazone, 9,10-anthracenedicarboxyaldehyde Bis[(4,5-dihydro-1H-imidazol-2-yl)hydrazone] dihydrochloride, against experimental tumors in mice.

9,10-Anthracenedicarboxaldehyde bis[(4,5-dihydro-1H-imidazol-2-yl)hydrazone] dihydrochloride (CL 216942; bisantrene hydrochloride; NSC 337766), a member of a new chemical class of compounds with antineoplastic properties, has been evaluated for antitumor activity in experimental murine tumor systems. The compound produced significant increases in life span (LS) and long-term survivors among mice bearing transplantable leukemias and solid tumors. Optimal treatment regimens resulted in an ILS of greater than 173 and 151% in mice with P388 and L1210 leukemia, respectively, an ILS of greater than 85% in mice with Lieberman plasma cell tumor, and an ILS of greater than 200, 150, and 63%, respectively, in mice with B16 melanoma, colon tumor 26, and Ridgway osteogenic sarcoma. An adriamycin-resistant subline of P388 leukemia showed complete cross-resistance to CL of 216942. The compound was active when administered by the i.p., i.v., and s.c. routes, but p.o. activity was not observed. Significant schedule dependency was not observed when the drug was administered once daily for 9 days, once every 4 days, or as a single dose, but single doses typically produced the best effects. CL 216942 was a potent inhibitor of DNA and RNA synthesis in L5178Y lymphoma cells cultured in vitro, and preliminary studies indicated the drug was a DNA-intercalating agent. The drug was cytotoxic for rapidly proliferating and nonproliferating (G0) human colon carcinoma WiDR cells in vitro.U