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11.
A gene known as Cyclon (cytokine-induced protein with coiled-coil domain) or CCDC86 (coiled-coil domain-containing protein 86) is known for its expression in leukocytes in mice, where it regulates the immune response. We investigated whether Cyclon/CCDC68 is expressed in leukocytes of schizophrenia patients and whether it might be used as a biological marker for the disease endophenotype segregation. We examined the level of mRNA of Cyclon/CCDC68 in white blood cells obtained from schizophrenia patients in relapse and remission as well as in healthy controls. The mRNA of Cyclon/CCDC68 was expressed by white blood cells of both schizophrenia patients and healthy controls. There was a dichotomous change in the levels of Cyclon/CCDC68 of relapsed patients before and after treatment. High Cyclon/CCDC68 levels were associated with a recent disease and presence of psychotic symptoms, while low levels were associated with a long duration of the disease and an absence of psychotic symptoms. These data indicate that Cyclon/CCDC68 levels correlate with the clinical presentation of relapsed schizophrenia. Cyclon/CCDC68 might be involved in the immune system disturbances observed in schizophrenia.  相似文献   
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In Biodemography, aging is typically measured and compared based on aging rates. We argue that this approach may be misleading, because it confounds the time aspect with the mere change aspect of aging. To disentangle these aspects, here we utilize a time-standardized framework and, instead of aging rates, suggest the shape of aging as a novel and valuable alternative concept for comparative aging research. The concept of shape captures the direction and degree of change in the force of mortality over age, which—on a demographic level—reflects aging. We 1) provide a list of shape properties that are desirable from a theoretical perspective, 2) suggest several demographically meaningful and non-parametric candidate measures to quantify shape, and 3) evaluate performance of these measures based on the list of properties as well as based on an illustrative analysis of a simple dataset. The shape measures suggested here aim to provide a general means to classify aging patterns independent of any particular mortality model and independent of any species-specific time-scale. Thereby they support systematic comparative aging research across different species or between populations of the same species under different conditions and constitute an extension of the toolbox available to comparative research in Biodemography.  相似文献   
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Shifts in species'' traits across contrasting environments have the potential to influence ecosystem functioning. Plant communities on unusually harsh soils may have unique responses to environmental change, through the mediating role of functional plant traits. We conducted a field study comparing eight functional leaf traits of seventeen common species located on both serpentine and non-serpentine environments on Lesbos Island, in the eastern Mediterranean. We focused on species'' adaptive strategies across the two contrasting environments and investigated the effect of trait variation on the robustness of core ‘leaf economic’ relationships across local environmental variability. Our results showed that the same species followed a conservative strategy on serpentine substrates and an exploitative strategy on non-serpentine ones, consistent with the leaf economic spectrum predictions. Although considerable species-specific trait variability emerged, the single-trait responses across contrasting environments were generally consistent. However, multivariate-trait responses were diverse. Finally, we found that the strength of relationships between core ‘leaf economic’ traits altered across local environmental variability. Our results highlight the divergent trait evolution on serpentine and non-serpentine communities and reinforce other findings presenting species-specific responses to environmental variation.  相似文献   
14.
W Champness  P Riggle  T Adamidis  P Vandervere 《Gene》1992,115(1-2):55-60
To define genetic elements that regulate antibiotic synthesis, we screened for mutations that visibly blocked synthesis of Streptomyces coelicolor's two pigmented antibiotics and found mutant strains in which all four antibiotics were blocked. The responsible mutations defined two loci, absA and absB. Two additional approaches to defining genes have been taken: isolation of cloned genes with a dominant negative effect on antibiotic synthesis and isolation of genes which, in multicopy, can compensate for specific mutational blocks. These genes apparently function in a global regulatory pathway (or network) for control of antibiotic synthesis.  相似文献   
15.
The filamentous soil bacterium Streptomyces coelicolor is known to produce four antibiotics which are genetically and structurally distinct. An extensive search for antibiotic regulatory mutants led to the discovery of absB mutants, which are antibiotic deficient but sporulation proficient. Genetic analysis of the absB mutants has resulted in definition of the absB locus at 5 o'clock on the genetic map. Multiple cloned copies of the actII-ORF4 gene, an activator of synthesis of the antibiotic actinorhodin, restore actinorhodin biosynthetic capability to the absB mutants. These results are interpreted to mean that the failure of absB mutants to produce antibiotics results from decreased expression of the antibiotic genes. The absB gene is proposed to be involved in global regulation of antibiotic synthesis.  相似文献   
16.

Background

The efferent dorsal motor nucleus of the vagal nuclei complex may degenerate early in the course of Parkinson’s disease (PD), while efferent nucleus ambiguous, the principal source of parasympathetic vagal neurons innervating the heart, and afferent somatosensory nuclei remain intact.

Objective

To obtain neurophysiological evidence related to this pattern, we tested processing of afferent sensory information transmitted via the auricular branch of the vagus nerve (ABVN) which is known to be connected to autonomic regulation of cardiac rhythm.

Methods

In this cross-sectional observational study, we recorded (i) somatosensory evoked potentials (ABVN-SEP) and (ii) cutaneo-cardioautonomic response elicited by stimulation of the ABVN (modulation of heart-rate variability (HRV index; low frequency power, ln(LF), high frequency power, ln(HF); ln(LF/HF) ratio)) in 50 PD patients and 50 age and sex matched healthy controls. Additionally, auditory evoked potentials and trigeminal nerve SEP were assessed.

Results

Neither ABVN-SEP nor any of the other functional brainstem parameters differed between patients and controls. Although HRV index was decreased in PD patients, modulation of ln(LF/HF) by ABVN-stimulation, likely indicating cardiac parasympathetic activation, did not differ between both groups.

Conclusions

Findings do not point to prominent dysfunction of processing afferent information from ABVN and its connected parasympathetic cardiac pathway in PD. They are consistent with the known pattern of degeneration of the vagal nuclei complex of the brainstem.  相似文献   
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Alyssum lesbiacum is a well-established Ni hyperaccumulator, endemic to serpentine soils of Lesbos Island (Greece). A total of 95 individuals were collected from 17 plots encompassing the only four large populations of this species. ISSR (Inter-simple sequence repeat) markers were used to assess genetic diversity and population structure of A. lesbiacum to provide initial guidance for the development of successful management and conservation measures. A total of ten primers produced 82 bands, 96.34 % being polymorphic. The largest part of total diversity was found within populations, rather than among them. AMOVA analysis partitioned the largest part of diversity within plots (66 %), while 15 % contained among plots within populations and 19 % among populations. Principal coordinates analysis along with dendrogram based on genetic distances among populations showed a high degree of genetic differentiation of the isolated population Loutra. At a smaller scale, distance was not the most significant factor influencing the patterns of genetic diversity, but topography, ecosystem types and connectivity through streams. According to our results, conservation efforts should be organized at the level of watersheds and ecosystem types, considering them as management units. For ex situ conservation and restoration, seed samplings should be representative of the different habitats and watersheds as well as the patches of large and small populations while keeping the east population of Loutra separate from the other three central populations, to avoid any loss of genetic diversity and to preserve the character of the local adapted populations.  相似文献   
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