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91.
Human enterovirus 109 (EV109) is a recently identified recombinant enterovirus in family Picornaviridae from acute paediatric respiratory illness in Nicaragua. EV109 have not been reported elsewhere. Our aims were the molecular detection and genetic analysis of EV109 from acute childhood respiratory infections in Hungary. Nasopharyngeal aspirates were collected from children under age of 10 years with acute respiratory infections treated in Department of Pulmonology, Kaposi Mór Teaching Hospital, Mosdós, Hungary. Samples were taken from 15 October to 15 May in two respiratory seasons 2005/2006 and 2006/2007. Samples were tested using EV109 specific VP1 primers by RT-PCR method. One (1.1%) of the 92 nasopharyngeal aspirates was positive for EV109 collected from a 2.5-year-old child in January, 2007. The main symptoms were dropping nose, fever (38.1°C), hard cough and wheezing associated with bronchitis and pneumonia. Based upon the VP1 gene region EV109 (L87/HUN/2007, JN900470) has 93% nucleotide identity and identical recombinant pattern to the prototype EV109. This is the first detection of the novel recombinant enterovirus, EV109, in Hungary (in Europe). This study supports the possibility that EV109 is able to cause acute respiratory infections, in addition, it might be plays a part in lower respiratory disease with hospitalization in children.  相似文献   
92.
Analyzing complex dynamics of ecological systems is complicated by two important facts: First, phenotypic plasticity allows individual organisms to adapt their reaction norms in terms of morphology, anatomy, physiology and behavior to changing local environmental conditions and trophic relationships. Secondly, individual reactions and ecological dynamics are often determined by indirect interactions through reaction chains and networks involving feedback processes.

We present an agent-based modeling framework which allows to represent and analyze ecological systems that include phenotypic changes in individual performances and indirect interactions within heterogeneous and temporal changing environments. We denote this structure of interacting components as COmplex Interaction Network (COIN).

Three examples illustrate the potential of the system to analyze complex ecological processes that incorporate changing phenotypes on the individual level:

• A model on fish population dynamics of roach (Rutilus rutilus) leads to a differentiation in fish length resulting in a conspicuous distribution that influences reproduction capability and thus indirectly the fitness.

• Modeling the reproduction phase of the passerine bird Erithacus rubecula (European Robin) illustrates variation in the behavior of higher organisms in dependence of environmental factors. Changes in reproduction success and in the proportion of different activities are the results.

• The morphological reaction of plants to changes in fundamental environmental parameters is illustrated by the black alder (Alnus glutinosa) model. Specification of physiological processes and the interaction structure on the level of modules allow to represent the reaction to changes in irradiance and temperature accurately.

Applying the COIN-approach, individual plasticity emerges as a structural and functional implication in a self-organized manner. The examples illustrate the potential to integrate existing approaches to represent detailed and complex traits for higher order organisms and to combine ecological and evolutionary aspects.

Keywords: Phenotypic plasticity; Indirect interactions; Complex interaction networks (COIN); Agent-based modeling; Individual-based modeling; Plant morphology; Fish energetics; Time-energy budgets; Rutilus rutilus; Erithacus rubecula; Alnus glutinosa  相似文献   

93.
Theory predicts that males adapt to sperm competition by increasing their investment in testis mass to transfer larger ejaculates. Experimental and comparative data support this prediction. Nevertheless, the relative importance of sperm competition in testis size evolution remains elusive, because experiments vary only sperm competition whereas comparative approaches confound it with other variables, in particular male mating rate. We addressed the relative importance of sperm competition and male mating rate by taking an experimental evolution approach. We subjected populations of Drosophila melanogaster to sex ratios of 1:1, 4:1, and 10:1 (female:male). Female bias decreased sperm competition but increased male mating rate and sperm depletion. After 28 generations of evolution, males from the 10:1 treatment had larger testes than males from other treatments. Thus, testis size evolved in response to mating rate and sperm depletion, not sperm competition. Furthermore, our experiment demonstrated that drift associated with sex ratio distortion limits adaptation; testis size only evolved in populations in which the effect of sex ratio bias on the effective population size had been compensated by increasing the numerical size. We discuss these results with respect to reproductive evolution, genetic drift in natural and experimental populations, and consequences of natural sex ratio distortion.  相似文献   
94.
The effects of neuropeptide F (NPF; from Moniezia expansa) on the regeneration of Girardia tigrina were studied. The animals were decapitated and incubated in water (control) or NPF. The dynamics of the proliferation of the neoblasts in the developing tissue were studied during the course of regeneration by monitoring the mitotic index (MI). The effects of incubation in FMRFamide and GYIRFamide on the MI were also tested. The course of cephalic regeneration was followed with in vivo computer-assisted morphometry for up to 7 days. The development of the regenerating nervous system and the musculature was visualised by immunostaining with a primary antiserum to the C-terminal decapeptide of NPF (YFAIIGRPRFa) and tetramethylrhodamine-isothiocyanate-conjugated phalloidin, which stains F-actin in muscle filaments. The study showed that NPF had a stimulatory effect on the mitotic activity of the neoblasts. FMRFamide and GYIRFamide did not have this effect. NPF also stimulated the growth of the regenerating head and the growing nervous system and musculature. NPF is postulated to have a morphogenetic action in the regenerating animals. This work was supported by two grants from the Finnish Academy of Science (nos. 202685, 2004) and (no. 112090, 2006) to M.G., an RFBR grant (07-04-00452a) to N.K. and a Wellcome Trust grant (069411) to A.G.M. for which we express our gratitude.  相似文献   
95.
96.
Proteasomes are energy-dependent proteases that are central to the quality control and regulated turnover of proteins in eukaryotic cells. Dissection of this proteolytic pathway in archaea, however, has been hampered by the lack of substrates that are easily detected in whole cells. In the present study, we developed a convenient reporter system by functional expression of a green fluorescent protein variant with C-terminal fusions in the haloarchaeon Haloferax volcanii. The levels of this reporter protein correlated with whole-cell fluorescence that was readily detected in culture. Accumulation of the reporter protein was dependent on the sequence of the C-terminal amino acid fusion, as well as the presence of an irreversible, proteasome-specific inhibitor (clasto-lactacystin β-lactone). This inhibitor was highly specific for H. volcanii 20S proteasomes, with a Ki of ~40 nM. In contrast, phenylmethanesulfonyl fluoride did not influence the levels of fluorescent reporter protein or inhibit 20S proteasomes. Together, these findings provide a powerful tool for the elucidation of protein substrate recognition motifs and the identification of new genes which may be involved in the proteasome pathway of archaea.  相似文献   
97.
Based on preliminary ethnographic research in five Javanese communities with major Hindu temples, I explore the political history and social dynamics of Hindu revivalism. I reject formalist approaches to the study of religion, including the notion of ‘syncretism’ and instead, treat the Hindu revival movements as an illustration of how social agents employ religious or secular concepts and values in their strategic responses to the particular challenges and crises they may face in a specific cultural, social, political and historical setting. Expectations of a great crisis at the dawn of a new golden age among followers of the Javanese Hindu revival movement are an expression of utopian prophesies and political hopes more widely shared among contemporary Indonesians. These expectations are set to shape the prospects of Indonesia's fledgling democracy. The paper reflects on the historical conditions under which these and similar utopian expectations and associated social movements may either incite violent conflict or serve a positive role in the creation or maintenance of a fair society.  相似文献   
98.
99.
The recidive-free phases, survival times and the number of long surviging patients were recorded in 64 children with cytochemically differentiated ALL. A significantly more favourable course of ALL of PAS type could be observed as compared with the undifferentiated type and partially with the esterase type, too. According to the present findings the cytochemical examinations of ALL can be recommended in the initial phase of leukaemia as a prognostic evaluation.  相似文献   
100.
The objective of this study was to determine if human oviduct specific glycoprotein (huOGP) would associate with hamster ovarian oocytes and human sperm during in vitro incubation. The huOGP used in these studies was partially purified from human hydrosalpinx fluid. Hamster ovarian oocytes and human sperm samples were incubated in culture medium with and without huOGP. Association of huOGP was assessed by indirect immunofluorescence assay using a polyclonal antibody prepared against huOGP. Intense fluorescence of the zona pellucida, and bright but uneven fluorescence of the perivitelline space, were observed in hamster ovarian oocytes following incubation in the presence of huOGP. A similar but more uniform pattern of fluorescence was observed when hamster oviductal oocytes (positive controls) were incubated in culture medium alone. Fluorescence was absent when oocytes were assayed with preimmune serum. The association of huOGP with the zona pellucida and perivitelline space appeared to be specific since thyroglobulin, a large molecular weight glycoprotein, and human serum albumin, the major protein in oviduct fluid, did not associate with the hamster oocytes nor inhibit huOGP association when included in the culture medium. Fluorescence was absent when human sperm incubated with huOGP were assayed with antiserum to huOGP. However, human sperm fluoresced when incubated with a uterine glycoprotein, CUPED, which had previously been shown to bind to cat sperm during in vitro incubation. Sperm also fluoresced brightly when human sperm antibody was used as a positive control. Solubilization of sperm membrane proteins postincubation and analysis of these proteins by 1-D SDS-PAGE followed by immunoblotting also failed to show an association of huOGP with human sperm. Electron microscopy of sperm both pre- and postsolubilization confirmed that the sperm membranes were removed by this process. In conclusion, the association of huOGP with hamster oocytes in vitro suggests that huOGP may associate with human oocytes in vivo, whereas that may not be true for human sperm in vivo. The association of huOGP with oocytes may serve to facilitate the process of fertilization and early embryonic development within the oviduct. © 1994 Wiley-Liss, Inc.  相似文献   
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