Sepsis: evolving concepts and challenges

Sepsis remains a major cause of morbidity and mortality worldwide, with increased burden in low- and middle-resource settings. The role of the inflammatory response in the pathogenesis of the syndrome has supported the modern concept of sepsis. Nevertheless, a definition of sepsis and the criteria for its recognition is a continuous process, which reflects the growing knowledge of its mechanisms and the success and failure of diagnostic and therapeutic interventions. Here we review the evolving concepts of sepsis, from the "systemic inflammatory response syndrome triggered by infection" (Sepsis-1) to "a severe, potentially fatal, organic dysfunction caused by an inadequate or dysregulated host response to infection" (Sepsis-3). We focused in the pathophysiology behind the concept and the criteria for recognition and diagnosis of sepsis. A major challenge in evaluating the host response in sepsis is to characterize what is protective and what is harmful, and we discuss that, at least in part, the apparent dysregulated host response may be an effort to adapt to a hostile environment. The new criteria for recognition and diagnosis of sepsis were derived from robust databases, restricted, however, to developed countries. Since then, the criteria have been supported in different clinical settings and in different economic and epidemiological contexts, but still raise discussion regarding their use for the identification versus the prognostication of the septic patient. Clinicians should not be restricted to definition criteria when evaluating patients with infection and should wisely use the broad array of information obtained by rigorous clinical observation.

Evaluation of apoptosis as a mechanism of follicular cell atresia in the ovaries of cattle (bos indicus) and buffalo (bubalus bubalis) fetuses

The objective of this study was to investigate the occurrence of apoptosis in the ovaries of cattle and buffalo fetuses between 4 and 8 months old by the terminal deoxynucleotidyltransferase - mediated dUTP nick end labeling (TUNEL) assay . Histological analysis of the ovarian t issue showed that apoptosis occurred at all ages evaluated , presenting a similar pattern among different fetal stages in both species . Within species, secondary follicles displayed a higher (P 0.05) of apoptotic follicular cells among the three follicular classes compared . C omparing resul ts between species, secondary follicles had a higher (P < 0.05) mean number of TUN EL positive cells in bovine fetuses; however , this difference was proportional to the larger number of follicular cells present in secondary follicles in this species . In summary, the TUNEL method was effective for the detection of apoptosis in the support ing cells of ovarian follicles from bovine and buffalo fetuses with apoptosis occurring at similar rates in both species between 4 and 8 months of gestational age. Further studies are needed to better understand the dynamics of apoptosis as a regulator of follicular atresia in fetal ovaries from these species, as well as the potential involvement of the oocyte in this process.

Morphological and morphometric aspects of Crassostrea rhizophorae (Guilding, 1828) oocytes in three stages of the gonadal cycle / Aspectos Morfológicos y Morfométricos de Oocitos de Crassostrea rhizophorae (Guilding, 1828) en Tres Fases del Ciclo Gonadal

Crassostrea rhizophorae (Guilding, 1828) es una de las especies de ostras tropicales cultivadas en la costa brasilera, que presenta alto valor comercial, no existiendo información sobre las características gonadales, durante las fases reproductivas de esta especie. El objetivo de este trabajo fue analizar la morfología de los ovocitos y de los folículos gonadales de Crassostrea rhizophorae, en tres fases del ciclo gonadal. Analizando los cortes histológicos de las gónadas y considerando los ovocitos que presentaban núcleo y nucléolo evidentes, fueron determinadas tres fases del ciclo gonadal: gametogénesis inicial, crecimiento y maduración. En la fase de gametogénesis inicial, el diámetro de los folículos y de los ovocitos era de 180,29 (+ - 41,91) e 18,66 (+ - 6,85) µm, respectivamente; también identificamos gran cantidad de tejido conjuntivo interfolicular y un número mayor de ovocitos previtelogénicos. En la fase de crecimiento, el diámetro de los folículos y de los ovocitos era de 218,02 (+ - 43,19) y 25,92 (+ - 9,94) µm, respectivamente. Este fase fue caracterizada por una pequeña cantidad de tejido conjuntivo interfolicular y predominio de ovocitos vitelogénicos. En la fase de maduración, el diámetro de los folículos y de los ovocitos era de 298,16 ( + - 99,24) y 35,27 (+ - 6,2) µm, respectivamente, existiendo gran número de ovocitos maduros. De esta manera, concluimos que durante la implantación del cultivo, Crassostrea rhizophorae tolera la influencia de los factores intrínsecos y extrínsecos y no presenta alteraciones significativas en su actividad reproductiva.

Crassostrea rhizophorae (Guilding, 1828) is one of the tropical species of oysters cultivated on the Brazilian shore. Despite its high commercial value, there is no information on the gonadal characteristics during the reproductive stages of this species. The objective of this work was to analyze the morphology and morphometry of Crassostrea rhizophorae oocytes and follicles in three stages of the gonadal cycle. Were analized histological sections of gonads considering that the oocytes presented visible nuclei and nucleoli, it was observed three gonadal cycle stages: early gametogenesis, growth and maturation. In the early gametogenesis stage, follicles and oocytes presented diameters of 180.29 (± 41.91) and 18.66 (± 6.85) µm, respectively, and presence of large amount of connective tissue and previtellogenic oocyte. In the growth stage, follicles and oocytes presented diameters of 218.02 (± 43.19) and 25.92 (± 9.94) µm, respectively, this stage was characterized by a small amount of interfollicular connective tissue with vitellogenic oocyte predominate. In the maturation stage, follicles and oocytes presented diameters of 298.16 (± 99.24) and 35.27 (± 6.2) µm, respectively, and presence of large number of mature oocytes. We concluded that during culture Crassostrea rhizophorae tolerates the influence of intrinsic and extrinsic factors and does not undergo significant changes in reproductive activity.

A novel polymorphic Alu insertion embedded in a LINE 1 retrotransposon in the human X chromosome (DXS225): identification and worldwide population study

We describe a novel polymorphic Alu insertion (DXS225) on the human X chromosome (Xq21.3) embedded into an L1 retrotransposon. The DXS225 polymorphism was genotyped in 684 males from the CEPH Human Genome Diversity Panel. This insertion was found in all regions of the globe, suggesting that it took place before modern humans spread from Africa ca. 100,000 years ago. However, only one Amerindian population (Karitiana) showed this insertion allele, which may have been introduced by European admixture. Thus, it appears likely that the Alu insertion was absent from pre-Columbian America. Analysis of molecular variance worldwide demonstrated that 92.2% of the genetic variance was concentrated within populations. DXS225 is flanked by two microsatellites (DXS8114 and DXS1002), which are 86 kb apart and are in very strong linkage disequilibrium. The combination of a unique event polymorphism on the X chromosome in linkage disequilibrium with two rapidly evolving microsatellites should provide a useful tool for studies of human evolution.

The leaves of green plants as well as a cyanobacterium, a red alga, and fungi contain insulin-like antigens

We report the detection of insulin-like antigens in a large range of species utilizing a modified ELISA plate assay and Western blotting. We tested the leaves or aerial parts of species of Rhodophyta (red alga), Bryophyta (mosses), Psilophyta (whisk ferns), Lycopodophyta (club mosses), Sphenopsida (horsetails), gymnosperms, and angiosperms, including monocots and dicots. We also studied species of fungi and a cyanobacterium, Spirulina maxima. The wide distribution of insulin-like antigens, which in some cases present the same electrophoretic mobility as bovine insulin, together with results recently published by us on the amino acid sequence of an insulin isolated from the seed coat of jack bean (Canavalia ensiformis) and from the developing fruits of cowpea (Vigna unguiculata), suggests that pathways depending on this hormone have been conserved through evolution