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51.
Hans-Christian Schaefer George W. Eshiamwata Fred B. Munyekenye & Katrin Böhning-Gaese 《Ibis》2004,146(3):427-437
The investigation of factors that cause differences in life-history traits between temperate and tropical birds is often hampered by a lack of knowledge about tropical species. Even within the well-known warblers of the genus Sylvia , which include resident species from temperate and tropical regions as well as migrants, there are few data from tropical species. We investigated the breeding biology of the tropical species Sylvia lugens and S. boehmi in a 2-year study in Kenya. Both species had a clutch size of 2.0 and laid c. 3.7 clutches per year. Breeding was characterized by long incubation periods ( S. lugens 14.5 days, S. boehmi 15.0 days), long nestling periods (16.0 and 12.9 days, respectively) and high predation rates (Mayfield nest success S. lugens 33.2%, S. boehmi 19.4%). Annual fecundity was 2.3 fledglings in S. lugens and 1.4 fledglings in S. boehmi . After fledging, the young birds were fed for 37.5 days ( S. lugens ) and 58.5 days ( S. boehmi ) (time to independence) and they stayed in their parents' territory for days or weeks, even after feeding had stopped. Fledgling survival until independence was 55.4% in S. lugens and 69.2% in S. boehmi . In general, S. lugens and S. boehmi have smaller but more numerous clutches, longer developmental periods, higher nest predation rates, lower annual fecundity and longer post-fledging care than their temperate congenerics. 相似文献
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We have previously characterized the centrosome/spindle pole-associated protein (CSPP) involved in cell cycle progression. The open reading frame C20orf55 was identified in a yeast two-hybrid screen in a search for CSPP-interacting proteins. A homology search revealed that C20orf55 belongs to a gene family consisting of three members that have not yet been described. The HUGO Nomenclature Committee has assigned these genes the names FAM110A-FAM110C. Studies of transfectants showed that the FAM110 proteins localized to centrosomes and accumulated at the microtubule organization center in interphase and at spindle poles in mitosis. In addition, overexpression of FAM110C induced microtubule aberrancies. Our data also indicated a cell cycle-regulated expression of FAM110A. Moreover, ectopic expression of FAM110B and FAM110C proteins impaired cell cycle progression in G1 phase. To summarize, we have characterized a novel family of genes encoding proteins with distinct conserved motifs, of which all members localize to centrosomes and spindle poles. 相似文献
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Wu AM Singh T Liu JH Krzeminski M Russwurm R Siebert HC Bonvin AM André S Gabius HJ 《Glycobiology》2007,17(2):165-184
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Shane A. Liddelow Katarzyna M. Dzi?gielewska Kjeld M?llg?rd Sophie C. Whish Natassya M. Noor Benjamin J. Wheaton Renate Gehwolf Andrea Wagner Andreas Traweger Hannelore Bauer Hans-Christian Bauer Norman R. Saunders 《PloS one》2014,9(9)
To maintain the precise internal milieu of the mammalian central nervous system, well-controlled transfer of molecules from periphery into brain is required. Recently the soluble and cell-surface albumin-binding glycoprotein SPARC (secreted protein acidic and rich in cysteine) has been implicated in albumin transport into developing brain, however the exact mechanism remains unknown. We postulate that SPARC is a docking site for albumin, mediating its uptake and transfer by choroid plexus epithelial cells from blood into cerebrospinal fluid (CSF). We used in vivo physiological measurements of transfer of endogenous (mouse) and exogenous (human) albumins, in situ Proximity Ligation Assay (in situ PLA), and qRT-PCR experiments to examine the cellular mechanism mediating protein transfer across the blood–CSF interface. We report that at all developmental stages mouse albumin and SPARC gave positive signals with in situ PLAs in plasma, CSF and within individual plexus cells suggesting a possible molecular interaction. In contrast, in situ PLA experiments in brain sections from mice injected with human albumin showed positive signals for human albumin in the vascular compartment that were only rarely identifiable within choroid plexus cells and only at older ages. Concentrations of both endogenous mouse albumin and exogenous (intraperitoneally injected) human albumin were estimated in plasma and CSF and expressed as CSF/plasma concentration ratios. Human albumin was not transferred through the mouse blood–CSF barrier to the same extent as endogenous mouse albumin, confirming results from in situ PLA. During postnatal development Sparc gene expression was higher in early postnatal ages than in the adult and changed in response to altered levels of albumin in blood plasma in a differential and developmentally regulated manner. Here we propose a possible cellular route and mechanism by which albumin is transferred from blood into CSF across a sub-population of specialised choroid plexus epithelial cells. 相似文献
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Erdur L Kallenbach-Dermutz B Lehmann V Zimmermann-Viehoff F Köpp W Weber C Deter HC 《BioPsychoSocial medicine》2012,6(1):4
Background
Anorexia nervosa is a severe psychosomatic disease with somatic complications in the long-term course and a high mortality rate. Somatic comorbidities independent of anorexia nervosa have rarely been studied, but pose a challenge to clinical practitioners. We investigated somatic comorbidities in an inpatient cohort and compared somatically ill anorexic patients and patients without a somatic comorbidity. In order to evaluate the impact of somatic comorbidity for the long-term course of anorexia nervosa, we monitored survival in a long-term follow-up. 相似文献58.
Kaltoft MS Skov Sørensen UB Slotved HC Konradsen HB 《Journal of microbiological methods》2008,75(3):540-544
In this paper, a simplified method for detection of pneumococcal carriage and for revealing the presence of several serotypes in a nasopharyngeal sample is evaluated. Enrichment broth was used for transportation and for the initial culturing of samples. All specimens were examined directly by the capsular reaction test for the presence of any of the 91 known pneumococcal serotypes. Sub-culturing on blood agar was used for isolation of the pneumococcal strains detected in the primary broth culture. A total of 693 nasopharyngeal swabs were obtained among children, their parents and employees in day care centres. Pneumococci were observed in 363 samples and 36 of these (9.9%) contained more than one serotype (multiple carriages). Two persons carried 3 different serotypes simultaneously. A significant increase in the positive sampling rate (5.8%) was achieved by using the simplified method compared to conventional streaking of the swabs directly on blood agar (p<0.0001). 相似文献
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Jüngling K Seidenbecher T Sosulina L Lesting J Sangha S Clark SD Okamura N Duangdao DM Xu YL Reinscheid RK Pape HC 《Neuron》2008,59(2):298-310
A deficient extinction of memory is particularly important in the regime of fear, where it limits the beneficial outcomes of treatments of anxiety disorders. Fear extinction is thought to involve inhibitory influences of the prefrontal cortex on the amygdala, although the detailed synaptic mechanisms remain unknown. Here, we report that neuropeptide S (NPS), a recently discovered transmitter of ascending brainstem neurons, evokes anxiolytic effects and facilitates extinction of conditioned fear responses when administered into the amygdala in mice. An NPS receptor antagonist exerts functionally opposing responses, indicating that endogenous NPS is involved in anxiety behavior and extinction. Cellularly, NPS increases glutamatergic transmission to intercalated GABAergic neurons in the amygdala via presynaptic NPS receptors on connected principal neurons. These results identify mechanisms of NPS in the brain, a key role of intercalated neurons in the amygdala for fear extinction, and a potential pharmacological avenue for treating anxiety disorders. 相似文献