Medical provisions for the immediate post-flight period following long space flights

At the final stage of long-term space flights first aid should be rendered in a specific way in cases of critical situations. Resuscitation and anesthesiology measures should be applied, if necessary, after study of flight-induced changes in the vital organs and systems. The paper describes the most important factors that should determine the tactics of resuscitation-anesthesiology support of the immediate postflight stage, if theoretically feasible acute life-endangering states develop. It also presents substantiated correction of routine clinical protocols of resuscitation aid.     

Repeated hypergravity: morphologic investigations of pituitary, thyroid, blood and bone marrow in rats

To elicit the mechanism of facilitating the mammals' adaptation to repeated changed gravity influence, the pituitary, thyroid, blood and bone marrow were investigated morphologically in rats exposed to single and repeated hypergravity (2 g) and Coriolis accelerations for 5 days during rotation on centrifuge. No distinct difference in blood and bone marrow cytology was determined after single and repeated exposure to 2 g and the Coriolis accelerations. Compared to single and in contrast to single and repeated exposures to the Coriolis accelerations, a repeated 2 g influence produced some structural changes in somatotropic cells of the pituitary and thyroid parenchyma of the thyroid. These changes were indicative of a significant intensification of synthesis and secretion of somatotropic and thyroid hormones. Elevated functional activity of the somatotropic cells and thyroid parenchyma during repeated exposure to 2 g appears to be a part of mechanism that makes adaptation to repeated hypergravity easier and points to the ability of mammals "to remember" changed gravity. It also advocates for the potentiality of intermittent centrifugation as a means of generating artificial gravity forces in space flight.     

cyclops encodes a nodal-related factor involved in midline signaling

Ventral structures in the central nervous system are patterned by signals emanating from the underlying mesoderm as well as originating within the neuroectoderm. Mutations in the zebrafish, Danio rerio, are proving instrumental in dissecting these midline signals. The cyclops mutation leads to a loss of medial floor plate and to severe deficits in ventral forebrain development, leading to cyclopia. Here, we report that the cyclops locus encodes the nodal-related protein Ndr2, a member of the transforming growth factor type beta superfamily of factors. The evidence includes identification of a missense mutation in the initiation codon and rescue of the cyclops phenotype by expression of ndr2 RNA, here renamed "cyclops." Thus, in interaction with other molecules implicated in these processes such as sonic hedgehog and one-eyed-pinhead, cyclops is required for ventral midline patterning of the embryonic central nervous system.     

Morphometric analysis of the extramacular retina from postmortem eyes with retinitis pigmentosa

Desmosomes are highly organized intercellular adhesive junctions that are particularly prominent in epidermis and other tissues experiencing mechanical stress. Desmoplakin, a constitutive component of the desmosomal plaque, is the most abundant protein present in such junctions and plays a critical role in linking the intermediate filament network to the plasma membrane in these tissues. Here we report the first mutation in the gene encoding desmoplakin. The identified mutation, resulting in a null allele and haploinsufficiency, was observed in genomic DNA from a kindred with the dominantly inherited skin disorder, striate palmoplantar keratoderma. Affected individuals had a linear pattern of skin thickening on the fingers and palms and circumscribed areas of skin thickening on the soles. Affected skin demonstrated loosening of intercellular connections, disruption of desmosome-keratin intermediate filament interactions and a proportion of rudimentary desmosomal structures. The disorder mapped to chromosome 6p21 with a maximum lod score of 10.67. The mutation was a heterozygous C-->T transition in exon 4 of the desmoplakin gene and predicted a premature termination codon in the N-terminal region of the peptide. This is the first reported mutation of desmo-plakin and also the first inherited skin disorder in which haploinsufficiency of a structural component has been implicated. It identifies dosage of desmoplakin as critical in maintaining epidermal integrity.     

Titanium diffusion in shinbone of rats with osseointegrated implants

Dental implants are composed of commercially pure Ti (which is actually an alloy of titanium, and minor or trace components such as aluminium and vanadium). When the implant is inserted, its surface undergoes a number of chemical and mechanical processes, releasing particles of titanium to the medium. The metabolism of free ions of titanium is uncertain; the uptaking processes in the body are not well known, nor their toxic dose. In addition, physical properties of newly formed bone, such as diffusivity and activation energy, are scarce and rarely studied. In this study, we analysed the diffusion of titanium in the titanium‐implanted shinbones of six adult male Wistar rats by spatially resolved micro x‐ray fluorescence. The measurements were carried out at the microfluorescence station of the x‐ray fluorescence (XRF) beamline of the Brazilian synchrotron facility LNLS (from Portuguese ‘Laboratorio Nacional de Luz Sincrotron’). For each sample, XRF spectra were taken by linear scanning in area near the new bone formed around the Ti implant. The scanning line shows a clear effect of titanium diffusion whereas calcium intensity presents a different behaviour. Moreover, a clear correlation among the different structures of bones is observed in the Ti and Ca intensities. The results obtained in these measurements may allow determining quantitatively the parameters of diffusion rates and other physical properties of new bone like diffusion coefficients.     

Effects of maintenance sessions on smoking relapse: Delaying the inevitable?

Fifty-seven smokers received a smoking cessation treatment consisting of rapid smoking and behavioral counseling. Additionally, subjects were assigned either to one of two maintenance treatments or to a nonmaintenance control condition. Both maintenance treatments comprised coping-response and Pavlovian-exposure training; one also included massed exposure to cigarettes (rapid-puffing trials). Maintenance meetings occurred 2, 4, 8, and 12 weeks after the cessation treatment. Compared with the control condition, both forms of maintenance sessions reduced relapse during the 12-week maintenance period but did not reduce relapse beyond that period. (PsycINFO Database Record (c) 2010 APA, all rights reserved)