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221.
The complete genome sequences of two Brazilian wild-type rabies viruses (RABV), a BR-DR1 isolate from a haematophagous bat (Desmodus rotundus) and a BR-AL1 isolate from a frugivorous bat (Artibeus lituratus), were determined. The genomes of the BR-DR1 and BR-AL1 had 11,923 and 11,922 nt, respectively, and both encoded the five standard genes of rhabdoviruses. The complete nucleotide sequence identity between the BR-DR1 and BR-AL1 isolates was 97%. The BR-DR1 and BR-AL1 isolates had some conserved functional sites revealed by the fixed isolates, whereas both isolates had unique amino acid substitutions in the antigenic region IV of the nucleocapsid gene. Therefore, it is speculated that both isolates were nearly identical in virologic character. According to our phylogenetic analysis based on the complete genomes, both isolates belonged to genotype 1, and to the previously defined "vampire bat-related RABV lineage" which consisted of mainly D. rotundus- and A. lituratus-isolates; however, a branch pattern with high bootstrap values suggested that BR-DR1 was more closely related to the 9001FRA isolate, which was collected from a dog bitten by a bat in French Guiana, than to BR-AL1. This result suggests that the vampire bat-related RABV lineage includes Brazilian vampire bat and Brazilian frugivorous bat RABV and is further divided into Brazilian vampire bat and Brazilian frugivorous bat RABV sub-lineages. The phylogenetic analysis based on the complete genomes was valuable in discriminating among very closely related isolates.  相似文献   
222.
Bone-loss-improving action of kudzu vine ethanol extracts (PVEE) was clarified. PVEE was composed roughly of 80% fiber, 10% puerarin, 3.6% daidzin, 2.5% 6″-O-malonyldaidzin, and the other minor isoflavones. Ten-week-old ovariectomized (OVX) mice were fed diets containing PVEE (20 mg/kg body weight/day) for 8 weeks. The bone resorption markers (urinary deoxypyridinoline and tartrate-resistant acid phosphatase activity) was elevated in OVX mice and was significantly decreased in OVX mice that consumed PVEE for 8 weeks. Consistent with the decrease in the markers, the number of matured osteoclasts in the distal femur was diminished in OVX mice fed PVEE diets. PVEE diets also suppressed the decrease in femoral bone mineral density (BMD) by OVX. PVEE showed the affinity for estrogen receptor α and β nearly 1/10000 weaker than 17β-estradiol. No hypertrophy in the uterus by the PVEE diet was observed. These results suggest that PVEE could be a promising resource for a functional food that improves osteoporosis.  相似文献   
223.
The purpose of the present study was to investigate the effect of milk in the early stage of lactation on the maturation of cholinergic neurons in the cerebral cortex of rats. Pups were removed from their mothers immediately following parturition and placed with foster dams at days 5–7 of lactation. At days 18 and 56 after birth, the activity of choline acetyltransferase (ChAT), an enzyme responsible for acetylcholine synthesis, in different areas of the cerebral cortex was examined by high‐performance liquid chromatography electrochemical detection. In the frontal and hindlimb/parietal regions of the cerebral cortex, the lack of early milk significantly decreased ChAT activity at days 18 and 56. There was no effect on gains in the body or brain weight of infants. ChAT activity in the occipital area tended to be lower in the early milk‐deprived rats. The intake of early milk potentially contributes not only to nutrients for the growth of newborn infants, but also to the functional maturation of the cholinergic neurotransmission system in a region‐specific manner.  相似文献   
224.
Organic-inorganic hybrid zeolite materials containing an organic framework have been synthesized by partially superseding a lattice oxygen atom by a methylene group. The use of methylene-bridged organosilane as a silicon source gives zeolite materials containing an organic group as lattice (ZOL), with several zeolitic phases such as the MFI and the LTA structures. Through various characterization methods, the presence of methylene frameworks (Si-CH2-Si) that replace siloxane bonds (Si-O-Si) has been verified, although the Si-C bonds are partly cleaved to give rise to terminal methyl groups. The shape-selective lipophilicity of a ZOL material indicates that it is not a physical mixture of conventional zeolite and amorphous organic-containing material but contains a genuine organic-inorganic hybrid zeolite.  相似文献   
225.
Antimicrobial therapy is a useful tool to control bovine mastitis caused by Staphylococcus aureus, as consequence an increase in staphylococci resistant cases has been registered. Alternative strategies are desirable and bacteriocins represent attractive control agents to prevent bovine mastitis. The aim of this work was to evaluate the activity of five bacteriocins synthesized by Bacillus thuringiensis against S. aureus isolates associated to bovine mastitis. Fifty S. aureus isolates were recovered from milk composite samples of 26 Holstein lactating cows from one herd during September 2007 to February 2008 in México and susceptibility of those isolates to 12 antibiotics and 5 bacteriocins from B. thuringiensis was evaluated. S. aureus isolates were mainly resistant to penicillin (92%), dicloxacillin (86%), ampicillin (74%) and erythromycin (74%); whereas susceptibility to gentamicin, trimethoprim and tetracycline was detected at, respectively, 92%, 88%, and 72%. All S. aureus isolates showed susceptibility to the five bacteriocins synthesized by B. thuringiensis, mainly to morricin 269 and kurstacin 287 followed by kenyacin 404, entomocin 420 and tolworthcin 524. Our results showed that S. aureus isolates had differences in the antimicrobial resistance patterns and were susceptible to bacteriocins produced by B. thuringiensis, which could be useful as an alternative method to control bovine mastitis.  相似文献   
226.
Polygonum thunbergii was selected among wild plants as a cadmium (Cd)-tolerant plant because of the high accumulation of Cd in the stems. However, the concentration of Cd in the leaves was low, which suggested the existence of an inhibitory mechanism of Cd translocation from stems to leaves. Observation of Cd distribution in stem-petiole-lamina in P. thunbergii plants that had absorbed Cd, using SEM-EPMA, revealed that Cd accumulation occurred mainly in the nodes, junctions of petioles, and vessels in stems, with minimal translocation in petioles. A detection method for tissue distribution of Cd was developed. Resin-fixed tissue tips were stained with a fluorescent probe BTC-5N and then sites of Cd location were detected with a fluorescence microscope. It was found that Cd in the stem tissues of P. thunbergii was distributed at specific sites of the cell walls of vessels and surrounding cells. The results were consistent with the findings of the investigation of Cd distribution in stem cells obtained by the cell fractionation method, which showed that most of Cd was present in the cell wall and cytoplasm. These results suggest that P. thunbergii accumulates Cd in specific cell walls of the stems and inhibits Cd-translocation to the leaves.  相似文献   
227.
Abstract

Many vegetable growers in Japan practice a unique waterlogged cultivation method with ample nitrogen (N) supply and microbial supplements, reporting vigorous plant growth, no soilborne diseases, and high yields. We simulated waterlogged soil conditions in greenhouse experiments to examine effects of soil pH and redox potential (Eh) as well as microbial influence on the growth of tomato seedlings. Soil pasteurization enhanced seedling growth whether the acidic, volcanic soil was waterlogged or well-drained. Among various antimicrobials, only soil treatment with polymyxin B improved shoot growth in nonpasteurized soil. The seedlings grew best in pasteurized acidic, waterlogged soil fertilized with ample potassium nitrate (KNO3), which maintained soil Eh above zero. In nonpasteurized soil, growth was severely stunted by raising soil pH progressively to 8.5 while Eh dropped to –194?mV. The results suggested that heat-sensitive Gram-negative soil bacteria and low soil Eh were key factors limiting the growth potential of tomato plants in waterlogged soils.  相似文献   
228.
Wheat grain size and shape are associated not only with yield but also with product and milling quality. A subspecies of cultivated tetraploid wheat, Triticum turgidum ssp. polonicum, is characterized by elongated glumes. To elucidate morphological effects of the subspecies differentiation-related gene, we conducted QTL analysis for grain and spikelet shape using a mapping population between two tetraploid wheat subspecies, polonicum and durum. P1, the gene controlling the elongated glumes, was located on chromosome 7A, and the polonicum-type allele acted in an incomplete dominance manner to express the elongated glume phenotype. The polonicum allele of the P1 locus significantly affected not only glume length but also grain shape, spike shape, awn length and seed fertility in tetraploid wheat. The elongated glume phenotype was correlated with an increase in spike length, grain length and grain weight, and with a decrease in fertility, grain number and awn length. Thus, the subspecies differentiation-related gene in subspecies polonicum dramatically affects grain shape accompanied by alteration of spikelet shape in tetraploid wheat.  相似文献   
229.
This study investigated how supplementation of the diet of dairy cows with trace minerals (zinc, manganese, copper and cobalt) affected kinematic gait parameters and lactation performance. Eight Holstein cows were divided into two groups, with each group receiving a different dietary treatment (control diet, or control diet supplemented with trace minerals) in a two‐period crossover design. Kinematic gait parameters were calculated by using image analysis software. Compared to cows fed the control diet, cows that received the trace mineral‐supplemented diet exhibited significantly increased walking and stepping rates, and had a shorter stance duration. Feed intake and milk production increased in cows fed the trace mineral‐supplemented diet compared with control groups. The plasma manganese concentration was not different in control and experimental cows. In contrast, cobalt was only detected in the plasma of cows fed the supplemented diet. These results provide the first evidence that trace mineral supplementation of the diet of dairy cows affects locomotion, and that the associated gait changes can be detected by using kinematic gait analysis. Moreover, trace mineral supplementation improved milk production and only minimally altered blood and physiological parameters in dairy cows.  相似文献   
230.
The development of ectopic gastric, intestinal, or pancreatic tissue in the gastrointestinal tract is extremely rare in rats, although it is fairly common in humans. In this report, we describe an unusual case in which a mixture of different types of ectopic tissue was found in the forestomach of a rat. A solitary white nodular/polypoid structure, which measured 5 mm in size, was detected on the luminal surface of the greater curvature of the forestomach in an 8-week-old female Crl:CD(SD) rat. A histological examination revealed that the lesion contained ectopic glandular gastric tissue, including gastric surface mucous cells, parietal cells, and pyloric gland cells, which was confirmed by immunohistochemistry. Moreover, the lesion also contained villin-positive columnar intestinal absorptive cells and chymotrypsin-positive pancreatic exocrine tissue. To the best of our knowledge, this is the first study to detect a mixture of ectopic glandular gastric, intestinal, and exocrine pancreatic tissue in a rat.  相似文献   
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