Transplants: bioethics and justice

Bioethics, as a branch of philosophy that focuses on questions relative to health and human life, is closely tied to the idea of justice and equality. As such, in understanding the concept of equality in its original sense, that is, in associating it to the idea to treat "unequals" (those who are unequal or different, in terms of conditions or circumstances) unequally (differentially), in proportion to their inequalities (differences), we see that the so-called "one-and-only waiting list" for transplants established in law no. 9.434/97, ends up not addressing the concept of equality and justice, bearing upon bioethics, even when considering the objective criteria of precedence established in regulation no. 9.4347/98, Thus, the organizing of transplants on a one-and-only waiting list, with a few exceptions that are weakly applicable, without a case by case technical and grounded analysis, according to each particular necessity, ends up institutionalizing inequalities, condemning patients to happenstance and, consequently, departs from the ratio legis, which aims at seeking the greatest application of justice in regards to organ transplants. We conclude, therefore, that from an analysis of the legislation and of the principles of bioethics and justice, there is a need for the creation of a collegiate of medical experts, that, based on medical criteria and done in a well established manner, can analyze each case to be included on the waiting list, deferentially and according to the necessity; thus, precluding that people in special circumstances be treated equal to people in normal circumstances.

Sobre o comportamento mitótico e meiótico de cromossomas policêntricos ou com ponto de inserção difuso

Material: Studies were made mainly with Ascaris megalocephála Cloq. univalens and bivalens, and also with Tityus bahiensis Perty. 1) Somatic pairing of heterochromatic regions. The heterochromatic ends of the somatic chromosomes in Ascaris show a very strong tendency for unspecifical somatic pairing which may occur between parts of different chromosomes (Figs. 1, 2, 3, 7, 10, 11, 12, 13, 14, 16, 18,), between the two ends of the same chromosome either directly (Figs. 4, 5, 7, 8, 11, 12, 13, 15, 16, 17, 18) or inversely (Fig. 8, in the arrow) and also within a same chromosomal arm (Fig. 6). 2) During the early first cleavage division the chomosomes are an isodiametric cylinder (Figs. 6, 9, 11, 13, 14). But in later metaphase the ends become club shaped (Figs. 1, 2, 3, 4, 5, 7, 10) which is interpreted as the beginning of migration of chromatic substance from the central euchromatic region towards the heterochromatic regions. This migration becomes more and accentuated in anaphase (Figs. 19, 22, 23) and in the vegetative cells where euchromatic region looses more and more staing power, especially in the intersititial zones between the individual small spherical chromosomes into which the euchromatic region desintegrates. The emigrated chromatin material is finally eliminated with the heterochromatic chromosome ends (Fig. 23 and 24). 3) It seems a general rule that during mitotic anaphase all chromosomes with diffuse or multiple spindle fiber attachement (Ascaris, Tityus, Luzula, Steatococcus, Homoptera and Heteroptera in general) move to the poles in the form of an U with precedence of the chromosomal ends. In Ascaris, the heterocromatic regions are pulled passively towards the poles and only the euchromatic central portion may be U-shaped (Fig. 19, 22, 25). While in the other species this U-shape is perfect since the beginning of anaphase, giving the impression that movement towards the poles begins at both ends of a chromosome simultaneously, this is not the case in Ascaris. There the euchromatic region is at first U-shaped, passing then to form a straight or zig-zag line and becoming again U-shaped during late anaphase. This is explained by the fact that the ends of the euchromatic regions have to pull the weight of the passive heterochromatic portions. 4) While it is generally accepted that, during first meio-tic division untill second anaphase, all attachement regions remain either undivided or at least united closely, this is not the case in chromosomes with diffused or multiple attachment. Here one clearly sees in all cases so far studied four parallel chromatids at first metaphase. In Luzula and Tityus (for Tityus all figs. 26 to 31) this division is allready quite clear in paraphase (pro-metaphase) and it cannot be said wether in other species the division in sister chromatids is allready present, but not visible at this stage. During first anaphase the sister chromatids of Titbits remain more or less in contact, while in Luzula and especially in Ascaris they are quite separated. Thus one can count in late anaphase or telophase of Ascaris megalocephala bivalens, nearly allways, four separate chromosomes near each pole, or a total of eight chromatids per division figure (Figs. 35, 36, 37, 38, 39, 40, 41).

O conceito de eletronegatividade na educação básica e no ensino superior

The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the electronegativity concept in high school and introductory college chemistry textbooks. Results obtained showed that most textbooks lacked history precedence and did not deal with the conceptual understanding and manifesting a strong standardization of characteristics that, from our point of view, do not favor the teaching-learning of the electronegativity concept.