Discrimination as a consequence of genetic testing.

Genetic discrimination refers to discrimination directed against an individual or family based solely on an apparent or perceived genetic variation from the "normal" human genotype. We describe here the results of a case history study designed to assess whether or not genetic discrimination exists. Using the above definition of genetic discrimination and applying stringent criteria for case selection, we find that genetic discrimination exists and is manifested in many social institutions, especially in the health and life insurance industries. Stigmatization, and denial of services or entitlements to individuals who have a genetic diagnosis but who are asymptomatic or who will never become significantly impaired, is noted. Follow-up comprehensive studies on the significance and varieties of genetic discrimination are needed. In order to avoid creating a new social underclass based on genetic discrimination (the "asymptomatic ill"), existing and future genetic testing or screening programs need review by medical, scientific, legal, and social policy experts, as well as the public, and may require modification.     

广州市代表性家庭的居民生活污水排放特征

针对目前城市生活污水排放量大、但居民排放底数不清的问题,选择广州市代表性家庭开展居民生活污水的定期调查,采用全天候全面收集、观测方法,定量分析广州城市居民的生活污水排放系数及特征.结果表明:城市居民人均日用水123.10 L,排出污水112.43 L.在居民日常生活排污中,洗衣水是最大的废水来源之一,而洗头水占比重最小.季节变化对居民用水量有一定影响,秋冬季节的日均用水及排水最要大于春夏季;家庭不同人群组成也对排水量有一定的影响,成年女性的生活污水排水量要高于成年男性和未成年人.     

Improvement of the shallow water communities following reductions of industrial outlets and sewage discharge in the Hvaler estuary,Norway

Three years' investigations of the shallow water communities at 30 different rocky shore sites in an estuary in southeast Norway were carried out during 1980–1982. The flora was mostly poor, possibly due to a combination of fresh water exposure, industrial and sewage outlets. The aim of these investigations was to establish the environmental status of the estuary prior to huge outlet reductions in 1989/90. Later reinvestigations during 1992–1994, following a significant reduction of titanium dioxide wastes and building of a new chemical sewage treatment plant have shown an improvement of the macroalgal and benthic animal communities. In the formerly most polluted area, the number of benthic taxa has increased since 1980–1982 by 50–350% in 1992–1994.     

Modeling of swarm formation as a consequence of autotaxis

The simple model of school and swarm formation is proposed within the frameworks of Eulerian space models (reaction-diffusion-advection system). Assuming that the schooling and the processes of birth-and-death act on different time scales, we have excluded the local kinetics of species (the reaction term) from the model. The spatial dynamics of animals is circumscribed by scalar field of density and vector field of velocity. The basis of animal aggregation in space is the ability of animals to move in certain direction, i.e. taxis. As an example of swarming strategy the behavior of midges is taken: we presume that individuals accelerate towards higher swarm density but change direction when the density exceeded some maximum. In other words, acceleration of movement is assumed to be proportional (with density-dependent coefficient of proportionality) to the gradient of species density. This statement poses the equation for species velocity. Thus, our model adds the differential equation for velocity of autotaxis to the standard advection-diffusion model. The linear analysis of 1D problem with zero-flux boundary conditions has showed that homogeneous nonzero equilibrium looses its stability when the movement rate of animals (coefficient of proportionality in velocity equation) overpasses some bifurcation value. The numerical experiments have confirmed analytical results, displaying stationary spatially heterogeneous solution (standing waves) for the detected supercritical value of the movement rate.     

Robust development as a consequence of generated positional information

The origin and robustness of morphogenesis are studied by dynamical system modeling of a cell society, in which cells possessing internal chemical reaction dynamics interact with each other through their mutual interaction with diffusive chemicals in a two-dimensional medium. It is found that stem-type cells differentiate into various cell types (where a cell 'type' is defined by a type of intra-cellular dynamics) due to a dynamic instability caused by cell-cell interactions in a manner described by the isologous diversification theory. The differentiations are spatially regulated by the concentration of chemicals in the medium, while the chemical concentrations are locally influenced by the intra-cell dynamics. Through this reciprocal relationship, chemical concentrations come to exhibit spatial variation as differentiated cell types begin to emerge, and as a result the regulation exercised by the chemical concentrations become spatially inhomogeneous. This reinforces the process of differentiation, through which spatial patterns of differentiated cells appear. Within this reciprocal relationship, the concentration gradients are read and interpreted by the cell as positional information. A spatial order of cells realized in this process represents a stable state of the system governed by this reciprocal relationship, and that the developmental process through which this state is realized is robust with respect to perturbations. The dependence of the morphogenesis on history and the community effect in cell differentiation are also discussed.     

Vitamin C stabilization as a consequence of the plasma membrane redox system

Summary Ascorbate is stabilized in the presence of HL-60 cells. Our results showed that cAMP derivatives and agents that increase cAMP stimulate the ability of HL-60 cells to stabilize ascorbate. On the other hand, tunicamycin, a glycosilation-interfering agent, inhibited this ability. The ascorbate stabilization in the presence of HL-60 cells has been questioned as a simple chemical effect. Further properties and controls about the enzymatic nature of this stabilization are described and discussed. This data, together with hormonal regulation, support the hypothesis that an enzymatic redox system located at the plasma membrane is responsible of the extracellular ascorbate stabilization by HL-60 cells.Abbreviations AFR ascorbate free radicals - FCS fetal calf serum - Sp-cAMPS Sp-cyclic adenosine monophosphothionate - Rp-cAMPS Rp-cyclic adenosine monophosphothionate     

Extralymphatic virus sanctuaries as a consequence of potent T-cell activation

T helper cells can support the functions of CD8(+) T cells against persistently infecting viruses such as murine lymphocytic choriomeningitis virus (LCMV), cytomegalovirus, hepatitis C virus and HIV. These viruses often resist complete elimination and remain detectable at sanctuary sites, such as the kidneys and other extralymphatic organs. The mechanisms underlying this persistence are not well understood. Here we show that mice with potent virus-specific T-cell responses have reduced levels and delayed formation of neutralizing antibodies, and these mice fail to clear LCMV from extralymphatic epithelia. Transfer of virus-specific B cells but not virus-specific T cells augmented virus clearance from persistent sites. Virus elimination from the kidneys was associated with the formation of IgG deposits in the interstitial space, presumably from kidney-infiltrating B cells. CD8(+) T cells in the kidneys of mice that did not clear virus from this site were activated but showed evidence of exhaustion. Thus, we conclude that in this model of infection, site-specific virus persistence develops as a consequence of potent immune activation coupled with reductions in virus-specific neutralizing antibodies. Our results suggest that sanctuary-site formation depends both on organ anatomy and on the induction of different adaptive immune effector mechanisms. Boosting T-cell responses alone may not reduce virus persistence.     

Psychiatric disturbance as a consequence of abnormal periodic cardiac variation

Abstract

The relationship between cardiac rate variation, resting sinus rhythm heart rate in beats per minute, and mental state is reviewed. A small series of 12 psychiatric patients in whom these variables were studied both before and after appropriate psychiatric treatment is reported. Comparison with the periodicity of cardiac rate variation in a normal group of subjects showed that the setting of the biological clock governing cardiac rate variation in psychiatric patients is abnormal, and in these cases running at a slower frequency than that of mental health. Appropriate psychiatric therapy re‐sets this clock in patients responding to treatment, but fails to do so in those patients who remain unimproved. Resting mean sinus rhythm heart rate in beats per minute does not show this relationship.     

Stream drift as a consequence of disturbance by invertebrate predators

Summary We carried out an experimental field study in a Swedish stream in order to determine whether mobile predators enhance the drift of stream insects. We increased the density of nymphs of the predaceous perlid stonefly, Dinocras cephalotes, in an experimental section of a stream up to densities in another more densely populated part of the same stream. The drift of several benthic species increased significantly compared to a control section where D. cephalotes were rare. Experiments carried out in September showed a strongly elevated drift response in nymphs of the mayfly Baetis rhodani only, whereas May experiments resulted in increased drift in B. rhodani as well as the amphipod Gammarus pulex, the stonefly Leuctra fusca, chironomids, and the total number of drifting animals. In September, we found that the drift response of Baetis rhodani to predator disturbance was dependent on the size of mayfly nymphs; small nymphs appeared in greater numbers in the drift nets than did large nymphs. A subsequent laboratory analysis of drift lengths of B. rhodani nymphs supported the hypothesis that small nymphs travel in the drift for longer than do large nymphs, particularly in darkness. We suggest that morphological constraints in vision or swimming performance, or both, cause small nymphs to drift longer. In May, size-dependent drift was less obvious, probably because the size of the nymphs was considerably greater than in September.