[Bone modeling in experimentally induced osteoporosis in rats].

Osteoporosis was experimentally induced in rats by ovariectomy (OVX), surgical excision of the sciatic nerve (NX), unilateral cordotomy (CX) and their combined operations. Each experimental group was sacrificed 12 or 24 weeks after the operation. Microdensitometrical findings, bone weight and the amount of tetracycline absorbed into the bone were examined and were compared with the control (sham op.

Probable assignment of soluble isocitrate dehydrogenase (IDH1) to 2q33.3.

Gene dosage effects for soluble isocitrate dehydrogenase (IDH1) were investigated in four unrelated cases with abnormalities involving the long arm of chromosome 2. Case 1 was trisomic for 2q33.3----qter, Case 2 monosomic for 2q33.

Grading score system: a method for evaluation of the degree of senescence in senescence accelerated mouse (SAM).

For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory.

Regional mapping of catalase and Wilms tumor--aniridia, genitourinary abnormalities, and mental retardation triad loci to the chromosome segment 11p1305----p1306.

Gene dosage effects for catalase (CAT) were studied in two unrelated patients with an interstitial deletion involving 11p13 to determine precisely the sites of the genes for CAT and the Wilms tumor--aniridia, genitourinary abnormalities, and mental retardation triad (WAGR) in the 11p13 band. Case 1 had the aniridia-Wilms tumor association, and case 2 showed the AGR triad. The karyotypes identified by high resolution banding techniques were 46,XY,del(11)(pter----p13::p11.

Antitumor agents LV: Effects of genkwadaphnin and yuanhuacine on nucleic acid synthesis of P-388 lymphocytic leukemia cells.

The diterpene esters, genkwadaphnin and yuanhuacine, have been shown to possess significant antileukemic activity in the P-388 screen. The major metabolic effects of the diterpene esters were on DNA and protein synthesis. The effects on DNA synthesis in vitro were evoked at a lower concentration than that required for protein synthesis inhibition.

Antitumor agents 57. The isolation and structural elucidation of microhelenin-E, a new antileukemic nor-pseudoguaianolide, and microhelenin-F from Helenium microcephalum.

Two new nor-pseudoguaianolides, microhelenin-E (1) and -F (2), were isolated from Texas Helenium microcephalum and their structures elucidated on the basis of physicochemical data and spectral evidence. Microhelenin-E demonstrated significant in vitro and in vivo cytotoxic and antileukemic activities against KB tissue cell culture (ED50 = 1.38 microgram/ml) P-388 lymphocytic leukemia growth in BDF1 male mice (T/C-166% at 8 mg/kg/day), respectively.

Amyloid deposition in the articular structures of AKR senescent mice.

Amyloid deposition in the articular structures occurred with high frequency in a strain of mice now being established as an animal model of senescence in this laboratory. The changes were most evident in the knee joint. Peripheral joints were always spared.

Studies on thermal adaptation in Tetrahymena membrane lipids. Changes in positional distribution of fatty acids in diacyl-phospholipids and alkyl-acyl-phospholipids during temperature acclimation.

The positioning of acyl chains in both 1-O-alkyl-2-acyl- and 1,2-diacyl-phospholipids was analyzed at various time intervals for a thermotolerant strain (NT-1) of Tetrahymena pyriformis cells during cold acclimation. During the 10 h period of adaptation, cells were not able to grow but maintained the ability to divide. The content of palmitate (16 : 0) in phosphatidylcholine and phosphatidylethanolamine was decreased after temperature-shift, with a concurrent increase of palmitoleate (16 : 1 delta 9) and gamma-linolenate (18 : 3 delta 6,9,12).

Cell cycle-associated changes of guanylate cyclase activity in synchronized Tetrahymena: a possible involvement of calmodulin in its regulation.

Guanylate cyclase activity decreased during the division phase of heat-shock synchronized Tetrahymena pyriformis, strain GL. However, when Ca2+ was removed by EGTA to negate the effects of the Ca2+-binding protein (calmodulin), which is required for the full activity of guanylate cyclase in this organism, no significant change in the enzymatic activity was observed throughout the cell cycle. On the other hand, the reduced guanylate cyclase activity at division phase was associated with a decreased level of calmodulin content.

Modification of membrane lipid composition following the nutritional shift-up of starved cells. A comparison with membrane biogenesis in Tetrahymena.

Detailed analyses of lipid composition have been made on various membrane fractions isolated at different intervals after 24 h-starved Tetrahymena cells were refed with nutrient-rich medium. During starvation there was a marked alteration in both phospholipid polar headgroup and acyl chain compositions: an increase in 2-aminoethylphospholipid and gamma-linolenic acid (18 : 3) with a concurrent decrease in phosphatidylethanolamine and palmitoleic acid (16 : 1). However, following refeeding, such an altered lipid composition was rather rapidly restored to the initial level of the control cell membranes prior to starvation.

Age-dependent modifications in membrane lipids: lipid composition, fluidity and palmitoyl-CoA desaturase in Tetrahymena membranes.

The membrane lipid composition of Tetrahymena pyriformis NT-I was observed to change in a manner markedly dependent on the progress of culture age. The pellicular, mitochondrial and microsomal membranes were isolated from cell harvested at various growth phases (I, early exponential; II, mid-exponential; III, late exponential; IV, early stationary; V, late stationary) and their lipid composition was analyzed by thin-layer and gas-liquid chromatography. Although the phospholipid composition varied somewhat among membrane fractions, the most general age-dependent alteration was a considerable decrease in the content of phosphatidylethanolamine accompanied by a small increase in phosphatidylcholine.

Regulatory mechanism of palmitoyl-CoA desaturase activity in thermal adaptation. Induction in non-growing Tetrahymena cells deprived of pre-existing desaturase.

The regulatory mechanism of palmitoyl-CoA desaturase activity in the downward temperature shift was investigated in the non-growing (starved) Tetrahymena cells. This cell system is advantageous in allowing depletion of the pre-existing palmitoyl-CoA desaturase. An unexpectedly profound increase in its activity was observed following temperature shift from 34 degrees C to 15 degrees C, providing evidence to support the concept that the increased level of the desaturase activity results from induction of the desaturase synthesis, probably by reutilization of degraded cell components, rather than from direct membrane fluidity control as observed in different experiments.

Morphogenesis and wall chemistry of the yeast, "intermediate," and hyphal phases of the dimorphic fungus, Mycotypha poitrasii.

When Mycotypha poitrasii (Zygomcetes) is grown under standard conditions in liquid culture containing 1% polypeptone, 0.5% yeast extract, and variable glucose concentrations (0-6%), it displays mycelial--yeast conversion. "Intermediate" cells, isolated from cultures containing 2% glucose, are considered to represent a developmental phase in the process of morphogenesis.