Effect of sequential medium on in vitro culture of goat ovarian cortical tissue

A sequential medium was evaluated on the survival, activation and growth rates of caprine preantral follicles submitted to a long-term culture period, aiming to establish an ideal in vitro culture system. Ovarian fragments were cultured for 16 days in α-MEM+ alone or supplemented with hormones (GH and/or FSH) added sequentially on different days of culture. Ovarian fragments were cultured in the first (days 0–8) and second (days 8–16) halves of the culture period, generating 10 treatments: α-MEM+/α-MEM+, FSH/FSH, FSH/GH, FSH/FSH + GH, GH/GH, GH/FSH, GH/FSH + GH, FSH + GH/FSH + GH, FSH + GH/FSH and FSH + GH/GH. Follicle morphology, viability and ultrastructure were analyzed. After day 1 of culture, FSH treatments maintained the percentage of normal follicles similar to the fresh control. At day 16 of culture, the treatment FSH/GH showed the highest (P < 0.05) percentage of normal follicles. The ultrastructure of follicles was preserved in the fresh control and FSH/GH treatment. Follicles cultured with FSH/GH had a higher (P < 0.05) viability than α-MEM+; however the viability was lower (P < 0.05) when compared to the fresh control. The FSH/GH treatment showed the highest (P < 0.05) percentage of follicular activation and secondary follicle formation and produced the largest (P < 0.05) mean follicular diameter after 16 days of culture. In conclusion, a sequential medium supplemented with FSH followed by GH during a long-term culture maintains the survival, viability and ultrastructure of goat preantral follicles, and promotes activation and secondary follicles

A method for finding new sets of axioms for classes of semigroups

We introduce a general technique for finding sets of axioms for a given class of semigroups. To illustrate the technique, we provide new sets of defining axioms for groups of exponent n, bands, and semilattices

Plant D-2-Hydroxyglutarate Dehydrogenase Participates in the Catabolism of Lysine Especially during Senescence

D-2-Hydroxyglutarate dehydrogenase (D-2HGDH) catalyzes the specific and efficient oxidation of D-2-hydroxyglutarate (D-2HG) to 2-oxoglutarate using FAD as a cofactor. In this work, we demonstrate that D-2HGDH localizes to plant mitochondria and that its expression increases gradually during developmental and dark-induced senescence in Arabidopsis thaliana, indicating an enhanced demand of respiration of alternative substrates through this enzymatic system under these conditions. Using loss-of-function mutants in D-2HGDH(d2hgdh1) and stable isotope dilution LC-MS/MS, we found that the D-isomer of 2HG accumulated in leaves of d2hgdh1 during both forms of carbon starvation. In addition to this, d2hgdh1 presented enhanced levels of most TCA cycle intermediates and free amino acids. In contrast to the deleterious effects caused by a deficiency in D-2HGDH in humans, d2hgdh1 and overexpressing lines of D-2HGDH showed normal developmental and senescence phenotypes, indicating a mild role of D-2HGDH in the tested conditions. Moreover, metabolic fingerprinting of leaves of plants grown in media supplemented with putative precursors indicated that D-2HG most probably originates during the catabolism of lysine. Finally, the L-isomer of 2HG was also detected in leaf extracts, indicating that both chiral forms of 2HG participate in plant metabolism

On the reliability of a simple method for scoring phenotypes to estimate heritability: A case study with pupal color in Heliconius erato phyllis, Fabricius 1775 (Lepidoptera, Nymphalidae)

In this paper, two methods for assessing the degree of melanization of pupal exuviae from the butterfly Heliconius erato phyllis, Fabricius 1775 (Lepidoptera, Nymphalidae, Heliconiini) are compared. In the first method, which was qualitative, the exuviae were classified by scoring the degree of melanization, whereas in the second method, which was quantitative, the exuviae were classified by optical density followed by analysis with appropriate software. The heritability (h2) of the degree of melanization was estimated by regression and analysis of variance. The estimates of h 2 were similar with both methods, indicating that the qualitative method could be particularly suitable for field work. The low estimates obtained for heritability may have resulted from the small sample size (n = 7-18 broods, including the parents) or from the allocation-priority hypothesis in which pupal color would be a lower priority trait compared to morphological traits and adequate larval development