Antibiotics and the Wasting Disease in Neonatally Thymectomized Rats

The administration of the antibiotic, Chloramphenicol, to pregnant rats just prior to, and for four days after delivery, diminishes the incidence of the so-called Wasting Disease in neonatally thymectomized rats. A total of 50 rats were divided into the following groups: Thymectomy only---nonmedicated 17 rats Thymectomy only---medicated 12 rats Thymectomy-adrenalectomy---nonmedicated 5 rats Thymectomy-adrenalectomy---medicated 8 rats Controls---nonmedicated 4 rats Controls---medicated 4 rats Chloramphenicol was administered in the drinking water to the mothers of groups 2, 4 and 6 for about 2 days prior to delivery and 4 days after. On the day of birth or within three days after birth, the male progeny were thymectomized. Approximately 2 weeks after thymectomy adrenalectomies were carried out on some of the progeny (groups 3 and 4). Growth rate and weight records were kept of all groups. At the 12th week white blood cell counts were made on all groups expect 1 and 3. At the end of the 24th week, all survivors were autopsied for presence of thymus and adrenal tissue and those with evidence of such were excluded. Routine tissue sections were made of various organs of all groups and search made for any evidence of hormonal deprivation or infection. The medicated control animals exhibited a higher growth rate than all other groups. The medicated thymectomized rats showed an average weight just slightly under that of the nonmedicated controls. The thymectomized-adrenalectomized animals appeared to show the same average weight at the end of the experiment but the medicated group had a faster growth rate and weight gain during the early weeks of the experiment. The medicated animals of groups 2 and 4 showed a 20 percent wasting incidence while wasting occurred in 40 percent of group 1 and 50 percent in group 3. The lowest white blood counts were 8,800 for the medicated thymectomized animals and 9,200 for the thymectomized-adrenalectomized animals, probably due to the lymphopenia reported by others. The white blood count of the nonmedicated control group was 12,000. The administration of antibiotic to a pregnant rat just prior to and for few days after birth of the young appears to lessen the incidence of the wasting disease in its progeny thymectomized within three days after birth leading to the conclusion that the wasting disease is primarily a pre-occupation of the immunologic system during the early weeks of life with infections acquired in the immediate post-operative period, These results corroborate the conclusions of Azar (1964) relative to the efficacy of antibiotic administration in preventing the wasting disease, and also are in accord with the findings of Miller (1964) that germ free thymectomized mice do not evidence the wasting syndrome

Cancer Biomarker Discovery: The Entropic Hallmark

Background: It is a commonly accepted belief that cancer cells modify their transcriptional state during the progression of the disease. We propose that the progression of cancer cells towards malignant phenotypes can be efficiently tracked using high-throughput technologies that follow the gradual changes observed in the gene expression profiles by employing Shannon's mathematical theory of communication. Methods based on Information Theory can then quantify the divergence of cancer cells' transcriptional profiles from those of normally appearing cells of the originating tissues. The relevance of the proposed methods can be evaluated using microarray datasets available in the public domain but the method is in principle applicable to other high-throughput methods. Methodology/Principal Findings: Using melanoma and prostate cancer datasets we illustrate how it is possible to employ Shannon Entropy and the Jensen-Shannon divergence to trace the transcriptional changes progression of the disease. We establish how the variations of these two measures correlate with established biomarkers of cancer progression. The Information Theory measures allow us to identify novel biomarkers for both progressive and relatively more sudden transcriptional changes leading to malignant phenotypes. At the same time, the methodology was able to validate a large number of genes and processes that seem to be implicated in the progression of melanoma and prostate cancer. Conclusions/Significance: We thus present a quantitative guiding rule, a new unifying hallmark of cancer: the cancer cell's transcriptome changes lead to measurable observed transitions of Normalized Shannon Entropy values (as measured by high-throughput technologies). At the same time, tumor cells increment their divergence from the normal tissue profile increasing their disorder via creation of states that we might not directly measure. This unifying hallmark allows, via the the Jensen-Shannon divergence, to identify the arrow of time of the processes from the gene expression profiles, and helps to map the phenotypical and molecular hallmarks of specific cancer subtypes. The deep mathematical basis of the approach allows us to suggest that this principle is, hopefully, of general applicability for other diseases

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

Food provisioning—from supermarket to producer: understanding the articulation of different suppliers

This special issue of theReview of Agricultural, Food and EnvironmentalStudiessets out to describe the social logics that enable consumers to manage theirrestrictions and resources, leading them to multimodal provisioning practices. Althoughit has become common to make use of multiple suppliers for food provisioning, theseplaces of commodification differ depending on each person’s restrictions. The fivearticles in this issue make important contributions on this point. In the first section ofthis introduction, we examine the way in which consumers mobilise these differentsuppliers, integrating different practices to authenticate foods. In the second section, welook at the complementarity of the disciplines and methods of this issue’sauthors,whoshare the same comprehensive approach. They pay special attention not only to themeaning consumers give to their provisioning but also to its material aspects, which weanalyse in the third section. Lastly, we return to the way in which all these studiesincorporate politics, economics and social aspects when analysing the commodificationand decommodification occurring in today’s food provisioning