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Lactobacillus rhamnosus GG (LGG) is a well‐established probiotic strain. The beneficial properties of this strain are partially dependent on its prolonged residence in the gastrointestinal tract, and are likely influenced by its adhesion to the intestinal mucosa. The pilin SpaC subunit, located within the Spa pili structure, is the most well studied LGG adhesion factor. However, the binding epitopes of SpaC remain largely unknown. The aim of this study was to evaluate the binding properties of SpaC to the carbohydrate moieties of intestinal glycoconjugates using a recombinant SpaC protein. In a competitive enzyme‐linked immunosorbent assay, SpaC binding was markedly reduced by addition of purified mucin and the mucin oligosaccharide fraction. Histochemical staining revealed that the binding of SpaC was drastically reduced by periodic acid treatment. Moreover, in the surface plasmon resonance‐based Biacore assay, SpaC bound strongly to the carbohydrate moieties containing β‐galactoside at the non‐reducing terminus of glycolipids. We here provide the first demonstration that SpaC binds to the oligosaccharide chains of mucins, and that the carbohydrate moieties containing β‐galactoside at the non‐reducing termini of glycoconjugates play a crucial role in this binding. Our results demonstrate the importance of carbohydrates of SpaC for mucus interactions.  相似文献   
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Twenty-one synthetic compounds, containing one or more furan rings, were demonstrated to possess anti-juvenile hormone (AJH) activity as evidenced by their induction of premature metamorphosis in the milkweed bug, Oncopeltus fasciatus (Dallas) by contact, topical application or fumigation. The ED50 of the four most active analogs required to induce precocious metamorphosis from 3rd-instar nymphs by residue contact in a Petri dish compared favorably with that of precocene II (6,7-dimethoxy-2,2-dimethyl 2H-chromene) a naturally occurring phytochemical AJH. Precocious metamorphosis was fully reversible by co-treatment with juvenile hormone (JH III) or JH analogs, demonstrating that the observed AJH activity resulted from an induced deficiency of juvenile hormone.  相似文献   
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Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.  相似文献   
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We isolated 629 fungi from 1296 berry seeds of solanaceous plants, including tomato (Lycopersicon esculentum), eggplant (Solanum melongena), bell pepper (Capsicum annuum), and red pepper (Capsicum annuum var. annuum) preserved for long and short terms. The isolates were classified into 22 genera excluding unidentified fungi, and the fungal floras were divided into two types: the tomato–eggplant and pepper groups. The results of cluster analysis with unweighted pair-group method with arithmetic average also supported these groups. Most tomato seeds infested with Geotrichum candidum germinated and grew the same as uninfested seeds. Cladosporium sphaerospermum and Arthrinium sp. isolated from eggplant seeds strongly suppressed germination, and Penicillium variabile suppressed seminal root elongation on eggplant. Alternaria alternata, Botrytis cinerea, and Myrothecium verrucaria detected from red pepper or bell pepper seeds were pathogenic to the fruits and the seedlings after artificial inoculation.  相似文献   
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Inter-section hybrids were obtained in the reciprocal crosses between Primula filchnerae (2n = 2x = 24) of Sect. Pinnatae and P. sinensis ‘Fanfare’ (2n = 2x = 24) of Sect. Auganthus by rescuing ovules on half-strength (1/2) Murashige and Skoog's (MS) medium supplemented with 50 g l−1 sucrose, 2.5 g l−1 gellan gum, 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 0.1 mg l−1 6-benzyladenine (BA) and 50 mg l−1 gibberellic acid (GA3). In ovule culture, germination occurred with radicle elongation but no plumule was observed. The radicle kept on the initial medium showed root proliferation with callus formation. When the calluses were transferred to (1/2)MS media containing 30 g l−1 sucrose and 3 g l−1 gellan gum, without plant growth regulators (PGRs) or with 1 mg l−1 zeatin and 0.1 mg l−1 NAA, plantlets were regenerated. The plants thus obtained were confirmed to be hybrids through flow cytometry (FCM) and random amplified polymorphic DNA (RAPD) analyses. The hybrid obtained when P. filchnerae was used as the maternal parent was diploid, whereas hexaploid hybrid was obtained when using P. sinensis as the maternal parent. The hexaploid hybrid might be produced through chromosome doubling of a triploid originated from the fertilization of P. sinensis with unreduced pollen of P. filchnerae.  相似文献   
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The relationship between the sugar content and absorption spectra was investigated using a near-infrared (NIR) spectrometer to visualize the sugar content of a melon. The absorbance at 676 nm, which is close to the absorption band of chlorophyll, exhibited a strong inverse correlation with the sugar content. A high-resolution cooled charged couple device imaging camera fitted with a band-pass filter of 676 nm was used to capture the spectral absorption image. The calibration method used for converting the absorbance values on the image into the degrees Brix sugar content was developed in accordance with NIR spectroscopy techniques. When this method was applied to each pixel of the absorption image, a color distribution map of the sugar content was constructed.  相似文献   
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To study the effect of pollination on fruit development in gynoecious and parthenocarpic cucumbers (Cucumis sativus L. cv. NK × AN8), the number of cells, cell size, mitotic index, histone H4 gene expression, and concentrations of endogenous cytokinins and auxin were compared in fruits that had developed from pollinated and non-pollinated flowers. Fresh weight was more in the pollinated group 4–12 days after anthesis (DAA) in both winter and spring, and 2–6 DAA in the summer. In winter, mitotic index increased from anthesis to 2 DAA and then decreased gradually in the pollinated group but immediately after anthesis in the non-pollinated group. Histone H4 gene in the pericarp zone was expressed more strongly during the period from pre-anthesis to 2 DAA in the pollinated group in summer. Concentrations of zeatin, isopentenyladenine, and indole-3-acetic acid (IAA) were higher in the non-pollinated group 2 and 4 DAA and peaked 4 DAA in spring whereas isopentenyladenine and IAA showed no distinct peaks in the pollinated group. These results are incompatible with the idea that pollination activates cell division by stimulating the synthesis of cytokinins and auxin in cucumber fruits.  相似文献   
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