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711.
While bipedalism is a fundamental evolutionary adaptation thought to be essential for the development of the human brain, the erect body is always an inch or two away from falling. Although the neural mechanism for automatically detecting one''s own body instability is an important consideration, there have thus far been few functional neuroimaging studies because of the restrictions placed on participants'' movements. Here, we used functional magnetic resonance imaging to investigate the neural substrate underlying whole body instability, based on the self-recognition paradigm that uses video stimuli consisting of one''s own and others'' whole bodies depicted in stable and unstable states. Analyses revealed significant activity in the regions which would be activated during genuine unstable bodily states: The right parieto-insular vestibular cortex, inferior frontal junction, posterior insula and parabrachial nucleus. We argue that these right-lateralized cortical and brainstem regions mediate vestibular information processing for detection of vestibular anomalies, defensive motor responding in which the necessary motor responses are automatically prepared/simulated to protect one''s own body, and sympathetic activity as a form of alarm response during whole body instability.  相似文献   
712.
α-Taxilin, a binding partner of the syntaxin family, is a candidate tumor marker. To gain insight into the physiological role of α-taxilin in normal tissues, we examined α-taxilin expression by Western blot and performed immunochemical analysis in the murine gastrointestinal tract where cell renewal vigorously occurs. α-Taxilin was expressed in the majority of the gastrointestinal tract and was prominently expressed in epithelial cells positive for Ki-67, a marker of actively proliferating cells. In the small intestine, α-taxilin was expressed in transient-amplifying cells and crypt base columnar cells intercalated among Paneth cells. In the corpus and antrum of the stomach, α-taxilin was expressed in cells localized in the lower pit and at the gland, respectively, but not in parietal or zymogenic cells. During development of the small intestine, α-taxilin was expressed in Ki-67-positive regions. Inhibition of cell proliferation by suppression of the Notch cascade using a γ-secretase inhibitor led to a decrease in α-taxilin- and Ki-67-positive cells in the stomach. These results suggest that expression of α-taxilin is regulated in parallel with cell proliferation in the murine gastrointestinal tract.  相似文献   
713.
A new psyllid species, Cacopsylla biwa Inoue, sp. nov., is described from Tokushima Prefecture, Shikoku, Japan. This new species develops only on Eriobotrya japonica (Thunb.) Lindl. (Rosaceae), causing severe damage to its fruits and flowers. It is strongly suspected that C. biwa is an alien species. Morphological similarities and host-plant relationships indicate that C. biwa is most closely related to Cacopsylla eriobotryae (Yang) comb. nov. (transferred from Edentatipsylla Li), which occurs in Taiwan and feeds on Eriobotrya deflexa (Hemsl.) Nakai. Morphological diagnostic characteristics of C. biwa and differences from the other congeners are discussed. Information is provided on the biology and life cycle of the new species.  相似文献   
714.
Patients with severe COPD are known to have comorbidities such as emaciation, cor pulmonale and right heart failure, muscle weakness, hyperlipemia, diabetes mellitus, osteoporosis, muscle atrophy, arterial sclerosis, hypertension, and depression. Therefore, treatment for COPD needs to focus on these comorbidities as well as the lungs. We previously reported a new mouse model of COPD utilizing the human surfactant protein C promoter SP-C to drive the expression of mature mouse IL-18 cDNA; constitutive IL-18 overproduction in the lungs of transgenic (Tg) mice induces severe emphysematous change, dilatation of the right ventricle, and mild pulmonary hypertension with aging. In the present study, we evaluated the progression of comorbidity in our COPD model. In female Tg mice, significant weight loss was observed at 16 weeks and beyond, when compared with control wild-type (WT) mice. This weight loss was suppressed in IL-13-deficient (knockout; KO) Tg mice. Muscle weight and bone mineral density were significantly decreased in aged Tg mice relative to control WT and IL-13 KO Tg mice. The aged Tg mice also showed impaired glucose tolerance. IL-18 and IL-13 may play important roles in the pathogenesis of comorbidity in COPD patients.  相似文献   
715.
The design and synthesis of 16-membered azalides modified at the C-15 and 4″ positions are described. The compounds we report here are characterized by an arylpropenyl group attached to the C-15 position of macrolactone and a carbamoyl group at the C-4″ position in a neutral sugar. Introduction of alkylcarbamoyl groups to the C-4″ position was regioselectively achieved by unique and convenient methods via acyl migration. As a result of optimization at the C-3 and 15 positions, several compounds were found to have potent activity against mef- and erm-resistant bacterial strains. These results suggest that 16-membered azalides could be promising compounds as clinical candidates.  相似文献   
716.
The viral 2A peptides have recently been used for bicistronic expression in various organisms. In this system, a single mRNA that codes for two proteins flanking the 2A peptide can be translated simultaneously into each protein by ribosomal skipping at this peptide sequence. Here, we tested the function of the Thosea asigna insect virus 2A (T2A) peptide in the branchiopod crustacean Daphnia magna—an emerging model of evolutionary developmental biology. First, we used transgenic Daphnia that expresses a potential bicistronic RNA containing mCherry and histone H2B‐ green fluorescent protein (GFP) open reading frames upstream and downstream of the T2A sequence, respectively. Microscopic observation revealed difference of localization of the two proteins in the cell, homogenous distribution of mCherry and nuclear localization of H2B‐GFP. Second, we changed localization of mCherry from cytoplasm to plasma membrane by attachment of a consensus myristoylation motif in the bicistronic reporter. RNA that codes for this new bicistronic reporter was injected into eggs. At gastrulation stage, we found spectrally distinct fluorescence with enough intensity and resolution to detect membrane localized mCherry and nuclear GFP. These results indicate that the T2A peptide functions in D. magna and T2A‐mediated bicistronic expression would be a promising tool for evo‐devo studies of this species.  相似文献   
717.
An isothermal ice recrystallization behavior in trehalose solution was investigated. The isothermal recrystallization rate constants of ice crystals in trehalose solution were obtained at ?5 °C, ?7 °C, and ?10 °C. Then the results were compared to those of a sucrose solution used as a control sample. Simultaneous estimation of water mobility in the freeze-concentrated matrix was conducted by 1H spin–spin relaxation time T2 to investigate mechanisms causing the different ice crystal recrystallization behaviors of sucrose and trehalose. At lower temperatures, lower recrystallization rates were obtained for both trehalose and sucrose solutions. The ice crystallization rate constants in trahalose solution tended to be smaller than those in sucrose solution at the same temperature. Although different ice contents (less than 3.6%) were observed between trehalose and sucrose solutions at the same temperature, the recrystallization behaviors of ice crystals were not markedly different. The 1H spin–spin relaxation time T2 of water components in a freeze-concentrated matrix for trehalose solution was shorter than in a sucrose solution at the same temperature. Results show that the water mobility of trehalose solutions in freeze-concentrated matrix was less than that of sucrose solutions, which was suggested as the reason for retarded ice crystal growth in a trehalose solution. Results of this study suggest that the replacement of sucrose with trehalose will not negatively affect deterioration caused by ice crystal recrystallization in frozen foods and cryobiological materials.  相似文献   
718.
Elucidating the physiological mechanisms of the irregular yet concerted flowering rhythm of mass flowering tree species in the tropics requires long‐term monitoring of flowering phenology, exogenous and endogenous environmental factors, as well as identifying interactions and dependencies among these factors. To investigate the proximate factors for floral initiation of mast seeding trees in the tropics, we monitored the expression dynamics of two key flowering genes, meteorological conditions and endogenous resources over two flowering events of Shorea curtisii and Shorea leprosula in the Malay Peninsula. Comparisons of expression dynamics of genes studied indicated functional conservation of FLOWERING LOCUS T (FT) and LEAFY (LFY) in Shorea. The genes were highly expressed at least 1 month before anthesis for both species. A mathematical model considering the synergistic effect of cool temperature and drought on activation of the flowering gene was successful in predicting the observed gene expression patterns. Requirement of both cool temperature and drought for floral transition suggested by the model implies that flowering phenologies of these species are sensitive to climate change. Our molecular phenology approach in the tropics sheds light on the conserved role of flowering genes in plants inhabiting different climate zones and can be widely applied to dissect the flowering processes in other plant species.  相似文献   
719.
The adsorption process of bovine serum albumin (BSA) onto a stainless steel surface was investigated using the quartz crystal microbalance based on admittance analysis. The adhered mass change ?m increased with time as a result of contacting the BSA solution, and considerably long period (>2 h) was required for the attainment of the asymptotic values of ?m as well as dissipation factor ?D. The relation between ΔD and Δm suggested that the layer of adsorbed BSA molecules became stiffer with increasing time at higher BSA concentration. The relation between Δm after 2 h and the final BSA concentration was described well by the Langmuir adsorption isotherm. However, the time course of Δm clearly deviated from the Langmuir adsorption model. The stretched exponential function model described the time course of Δm well although it was an empirical one.  相似文献   
720.
Proteoglycan (PG) is a heavily glycosylated protein, localized to cell surface and extracellular matrix, and has various functions. Recently, it has been gradually revealed that PG interacts with various growth factors and morphogens and regulates cellular functions. Although salmon nasal cartilage PG (Salmon-PG) increases proliferation of immortalized cells, its mechanism remains unclear. In this study, we confirmed the effect of Salmon-PG on normal human dermal fibroblast (NHDF) and investigated the mechanism of PG action on NHDF. Salmon-PG dose- and time-dependently increased NHDF proliferation. Receptor tyrosine kinase array revealed that Salmon-PG increased only Erk1/2 signaling. Erk1/2 phosphorylation was significantly increased by Salmon-PG in a time-(10 min) and dose-(400 or 800 μg/mL) dependent manner. MEK inhibitor suppressed the enhancement of NHDF proliferation by Salmon-PG. The overall findings indicate that Salmon-PG plays a role as a growth factor in NHDF via Erk1/2 activation, suggesting that Salmon-PG contributes to the maintenance of skin homeostasis.  相似文献   
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