Endogenous respiration and regulation in a primitive marine fungus

The relationship between the respiration and the presence and utilization of endogenous and exogenous substrates was studied in the non-filamentous obligately marine fungus Thraustochytrium aureum. Using isotopic and manometric methods, it was shown that almost all exogenous glucose is assimilated, whilst almost all the oxygen consumption in the presence of exogenous glucose was due to oxidation of endogenous reserves. In contrast, exogenous glutamate, which cannot serve as the sole carbon source for growth, inhibits respiration of endogenous materials, and is itself rapidly oxidized. The uncoupler 2,4-dinitrophenol stimulates the oxidation of endogenous reserves without affecting the uptake and use of exogenous glucose. These data strongly support the idea of physiologic compartmentation in this organism.     

A general synthesis of long chain ω- and (ω-1)-hydroxy fatty acids

A method for the synthesis of long chain fatty acids substituted at the ω and ω-1 positions has been developed. The key step is the isomerization of the triple bond of an alkyn-1-ol from an internal position in the chain to the free terminus with a new, convenient reagent, sodium aminopropylamide (NaAPA). Standard functional group manipulations i.e., Jones oxidation, esterification and hydroboration of the triple bond are used to prepare ω-hydroxy fatty esters. The generality of the method is illustrated with syntheses of ω-hydroxy fatty esters with 24, 26, 28 and 30 carbon chains.In the 24 carbon series, hydration of the terminal triple bond of alkynoic ester 4a followed by reduction gave the (ω-1)-hydroxy ester.     

Program of early development in the mammal: Synthesis and intracellular migration of histone H4 during oogenesis in the mouse

Synthesis of histone H4 by mouse oocytes and unfertilized eggs has been examined by using a modified high-resolution two-dimensional gel electrophoresis procedure capable of resolving basic proteins (M. J. LaMarca and P. M. Wassarman, 1979, Develop. Biol.73, 103–119). Histones were separated on such gels and observed rates of incorporation of [³⁵S]methionine into histone H4 were converted into absolute rates of synthesis by using previously determined values for the absolute rates of total protein synthesis in mouse oocytes and unfertilized eggs Schultz et al., 1979a, Schultz et al., 1979b. Histone H4 was synthesized at all stages of oogenesis examined, and accounted for 0.07, 0.05, and 0.04% of total protein synthesis in growing oocytes, fully grown oocytes, and unfertilized eggs, respectively. During oocyte maturation the absolute rate of histone H4 synthesis decreased by about 40%, as compared to a 23% decrease in the rate of total protein synthesis during the same period. These measurements indicate that enough histone is synthesized during oogenesis in the mouse to support two to three cell divisions. Examination of the intracellular location of newly synthesized proteins in fully grown oocytes revealed that histone H4 was highly concentrated in the nucleus (germinal vesicle), whereas total protein and tubulin were not. Nearly 50% of the histone H4 synthesized during a 5-hr period was located in the oocyte's germinal vesicle, as compared to 1.9 and 0.9% for total protein and tubulin, respectively. These results are compared with those obtained using oocytes and eggs from nonmammalian animal species.     

Serum FSH, LH and testosterone in the male rhesus following prostaglandin injection.

Adult male rhesus were treated with PGE2, PGF2 alpha or the 13,14-dihydro-15-keto metabolite of PGE2 in a randomized crossover design. Serum concentrations of FSH, LH and testosterone were determined and compared to the respective values in the same uninjected animals. No significant changes were noted in controls or following the metabolite injection. FSH increased gradually for 4 hours after metabolite treatment. In contrast, injection of PGF2 alpha was followed by an abrupt (within 15 minutes) increase in LH and testosterone. FSH increased gradually in 2 of 3 treated animals. Injection of PGE2 was followed by a similar abrupt increase in LH concentration. This was not always associated with a significant increase in testosterone or FSH. These results demonstrate that injections of PGE2 or PGF2 alpha can change serum gonadotropin and testosterone concentrations in male rhesus monkeys, and that the effects of these two prostaglandins are qualitatively different.     

Characterization of surface alloantigens of murine neutrophils

Serological analysis of highly purified (>97%) mouse peritoneal exudate neutrophils using a protein-A rosetting technique, showed that these cells possessed the surface phenotype: Ig^–, Thy-1^–, Ly-1^–, Ly-2^–, Ly-3^–, Ly-4⁺, Ly-5⁺, Ly-6⁺, Ly-7^–, Ia^–, FcR⁺ and C3R⁺.     

Influence of dietary Ca, Mg, and P on cyclic-AMP excretion and kidney calcification in the rat.

A series of five experiments was conducted with young male albino rats to investigate effects of various levels of dietary Ca, P and Mg on urinary cAMP excretion and kidney calcification. Urinary cAMP excretion was shown to be directly correlated with injected parathyroid (PT) hormone dose level and to be inversely associated with dietary Ca intake. Thus, cAMP excretion may be presumed to reflect PT activity in the young rat. Magnesium deficiency tended to reduce cAMP excretion, while P excess did not affect it. Each treatment induced kidney calcification. Calcium deficiency increased cAMP excretion irrespective of Mg status, although nephrocalcinosis appeared only in the Mg-deficient animals. These data support the view that nephrocalcinosis of dietary origin in the rat is not mediated by increased PT activity.     

Morphological changes of the surface of the egg of Xenopus laevis in the course of development: III. Scanning electron microscopy of gastrulation

Cell surface changes occurring before and during gastrulation in Xenopus laevis embryos have been examined by scanning electron microscopy (SEM). Our study covers the period of development from very young blastulae (stage 7) to late gastrulae (stage $\text{12}\text{1}\text{2}$. Before the onset of the epibolic movement there is evidence of locomotory activity of the cells lining the blastocoel at the animal pole. In the medim- (stage 8) and small-cell (stage 9) blastula, when pregastrulation movements are progressing rapidly, microvilli appear in the interstices between cells, both at the animal and at the vegetal pole. In the gastrula, most of the cells close to the blastopore have either their entire exposed surface or part of it covered with microvilli. On the other hand, the cells that have just reached the blastopore and have become clubshaped do not display microvilli on their surfaces; microvilli are also absent on the surface of the cells that have undergone invagination. The invaginated chorda-mesoderm is made up of single fibroblastlike cells with long thin filopodia which are interwoven with those of nearby cells. The observations are discussed in relation to changes in cell-to-cell connections and to the role of cell surface organization in the morphogenetic movements of gastrulation.     

A 10-miRNA risk score-based prediction model for pathological complete response to neoadjuvant chemotherapy in hormone receptor-positive breast cancer

Patients with hormone receptor(HR)-positive tumors breast cancer usually experience a relatively low pathological complete response(p CR) to neoadjuvant chemotherapy(NAC). Here, we derived a 10-micro RNA risk score(10-mi RNA RS)-based model with better performance in the prediction of p CR and validated its relation with the disease-free survival(DFS) in 755 HRpositive breast cancer patients(273, 265, and 217 in the training, internal, and external validation sets, respectively). This model,pres...