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1.
Differences in sugar distribution between the villous epithelium and follicle-associated epithelium (FAE) were compared using lectins in the rabbit small intestine. In every portion, villous columnar epithelial cells primarily exhibited a positive reaction to the GalNAc, GlcNAc, galactose, and oligosaccharide. In the ileal Peyer's patch (PP), whereas microvillous epithelial cells exhibited positive reactions, M cells tended to be negative. The villous epithelial reaction to the fucose group was negative, but M cells and microvillous epithelial cells showed a positive to the fucose. No epithelium had a positive reaction to the mannose and glucose. The variety of lectin-binding properties of villous epithelial cells and M cells may reflect specificity for the recognizing luminal substances such as antigenic molecules and bacterial elements.  相似文献   
2.
The siderophore avaroferrin (1), an inhibitor of Vibrio swarming that was recently identified in Shewanella algae B516, was produced by heterologous expression of the biosynthetic gene cluster cloned from a deep-sea sediment metagenomic DNA, together with two analogues, bisucaberin (2) and putrebactin (3). Avaroferrin (1) is a macrocyclic heterodimer of N-hydroxy-N-succinyl cadaverine (4) and N-hydroxy-N-succinyl-putrescine (5), whereas analogues 2 and 3 are homodimers of 4 and 5, respectively. Heterologous expression of two other related genes from culturable marine bacteria resulted in production of compounds 1–3, but in quite different proportions compared with production through expression of the metagenomic DNA.  相似文献   
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A typhoon event catastrophically destroyed a 45-year-old Japanese larch plantation in southern Hokkaido, northern Japan in September 2004, and about 90% of trees were blown down. Vegetation was measured to investigate its regeneration process and CO2 flux, or net ecosystem production (NEP), was measured in 2006–2008 using an automated chamber system to investigate the effects of typhoon disturbance on the ecosystem carbon balance. Annual maximum aboveground biomass (AGB) increased from 2.7 Mg ha−1 in 2006 to 4.0 Mg ha−1 in 2007, whereas no change occurred in annual maximum leaf area index (LAI), which was 3.7 m2 m−2 in 2006 and 3.9 m2 m−2 in 2007. Red raspberry (Rubus idaeus) had become dominant within 2 years after the typhoon disturbance, and came to account for about 60% and 50% of AGB and LAI, respectively. In comparison with CO2 fluxes measured by the eddy covariance technique in 2001–2003, for 4.5 months during the growing season, the sum of gross primary production (GPP) decreased on average by 739 gC m−2 (64%) after the disturbance, whereas ecosystem respiration (RE) decreased by 501 gC m−2 (51%). As a result, NEP decreased from 159 ± 57 gC m−2 to −80 ± 30 gC m−2, which shows that the ecosystem shifted from a carbon sink to a source. Seasonal variation in RE was strongly correlated to soil temperature. The interannual variation in the seasonal trend of RE was small. Light-saturated GPP (Pmax) decreased from 30–45 μmol m−2 s−1 to 8–12 μmol m−2 s−1 during the summer season through the disturbance because of large reduction in LAI.  相似文献   
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Myofibrillar proteins of vertebrate skeletal muscles are insoluble in solutions of ionic strength that approximate physiological conditions. We established a method to solubilize more than 80% of chicken breast muscle myofibrillar proteins in water for the use of meat as a source of food protein. SDS‐polyacrylamide gel electrophoretic patterns of water‐soluble myofibrillar proteins demonstrated that all identified myofibrillar proteins except connectin/titin were soluble in water. A part of α‐actinin was released from myofibrils by repeated washing with 2.5 mmol/L NaCl and 5 mmol/L L‐histidine solution, and subsequent destruction of connectin/titin in washed myofibrils by ultrasonication resulted in solubilization of a large fraction of chicken breast muscle myofibrillar proteins in water. Myofibrillar proteins of chicken leg, pork loin, beef shoulder loin, and lamb were also solubilized in water using this procedure.  相似文献   
7.
Measles virus (MV) infection primarily targets epithelial cells of the respiratory tract, which have the potential to synthesize a variety of cytokines. In this report, we studied the effect of MV infection on the production of interleukin (IL)-8 by the pulmonary epithelial cells. A549 cells, a lower airway epithelial cell line, produced IL-8 after MV inoculation in a dose- and time-dependent manner. The IL-8 production was little affected by UV-inactivation of MV and scarcely suppressed by cycloheximide treatment. These results indicated that MV particle binding to and/or incorporation into cells stimulated IL-8 expression in A549 cells.  相似文献   
8.
In order to understand the relationship between lactic acid bacteria (LAB) species and silage fermentation, a total of 65 LAB strains isolated from mixed pasture of timothy (Phleum pratense L.) and orchardgrass (Dactylis glomerata L.), and its badly preserved silages were subjected to phenotypic and genetic analysis. According to these analyses, the isolates were divided into 13 groups, including Enterococcus gallinarum, Lactobacillus acidipiscis, L. coryniformis subsp. coryniformis, L. coryniformis subsp. torquens, L. curvatus, L. paraplantarum, L. plantarum subsp. argentoratensis, L. plantarum subsp. plantarum, L. sakei subsp. carnosus, Lactococcus garvieae, Lactococcus lactis subsp. cremoris, Leuconostoc pseudomesenteroides, Pediococcus acidilactici, Pediococcus pentosaceus, Weissella hellenica, Weissella paramesenteroides and Carnobacterium divergens. This is the first report to document that C. divergens, L. acidipiscis, L. sakei subsp. carnosus, L. garvieae, phenotypically novel L. lactis subsp. cremoris, E. gallinarum and W. hellenica are present in vegetative forage crops. L. plantarum group strains were most frequently isolated from the badly preserved silages. Some isolates showed a wide range of growth preferences for carbohydrate utilization, optimal growth pH and temperature in vitro, indicating that they have a high growth potential. These results are useful in understanding the diversity of LAB associated with decayed silage of timothy and orchardgrass.  相似文献   
9.
Myogenesis is precisely proceeded by myogenic regulatory factors. Myogenic stem cells are activated, proliferated and fused into a multinuclear myofiber. Pax7, paired box 7, one of the earliest markers during myogenesis. It has been reported that Pax7 regulates the muscle marker genes, Myf5 and MyoD toward differentiation. The possible roles of Pax7 in myogenic cells have been well researched. However, it has not yet been clarified if Pax7 itself is able to induce myogenic fate in nonmyogenic lineage cells. In this study, we performed experiments using stably expressed Pax7 in 3T3‐L1 preadipocytes to elucidate if Pax7 inhibits adipogenesis. We found that Pax7 represses adipogenic markers and prevents differentiation. These cells showed decreased expression of PDGFRα, PPARγ and Fabp4 and inhibited forming lipid droplets.  相似文献   
10.
A 2-year-old Thoroughbred filly presented with ocular pain and epiphora of the left eye. The pupil was miotic and the cornea edematous near the ventro-temporal limbus, but did not retain any fluorescein. The topical antibiotics and atropine and diclofenac, and systemic flunixin meglumine and antibiotic therapy did not resolve the condition. A pink and fleshy infiltrate developed near the limbus indicating nonulcerative keratouveitis. The anterior uveitis deteriorated as manifested by the presence of dyscoria, hypopyon, and organized fibrin in the anterior chamber. Ocular signs were improved by topical and subconjunctival corticosteroids, but repeatedly deteriorated as the frequency of medication was reduced. The horse was seropositive to three serovars of Leptospira interrogans. The animal was diagnosed as blind on day 91 by the absence of pupillary light and menace reflexes, and donated for histopathologic diagnosis. The corneal opacity was histologically fibrotic and infiltrated predominantly by lymphocytes with Descemet's membrane partially disrupted by macrophages. The choroid was infiltrated by lymphocytes, eosinophils and basophils, and was positive to IgG and C3. There were filamentous or spiral structures positive to Warthin-Starry stain in the renal cortex. There was also polymerase chain reaction amplification of the leptospiral gene in the kidney. From these findings nonulcerative keratouveitis was believed to be caused by systemic infection with Leptospira.  相似文献   
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