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271.
272.
This study aimed to detect filarial parasites in blood samples of Japanese black bears (Ursus thibetanus japonicus) collected from Iwate Prefecture, Japan. Positive amplicons were obtained from 26 out of 30 samples by nested PCR targeting 18S ribosomal RNA gene and first internal transcribed spacer regions. DNA sequences of Mansonella sp. close to M. ozzardi and Dirofilaria sp. were detected for eight and 11 positive amplicons, respectively. Co-infection was detected for the remaining seven amplicons. Dirofilaria sp. was identified as D. ursi by further genetic analysis of 5S ribosomal RNA gene sequence. The results of this study will contribute to further investigations of Japanese black bears for monitoring their risk as a reservoir of possible zoonotic filarial parasites.  相似文献   
273.
We report the direct observation of dioxygen molecules physisorbed in the nanochannels of a microporous copper coordination polymer by the MEM (maximum entropy method)/Rietveld method, using in situ high-resolution synchrotron x-ray powder diffraction measurements. The obtained MEM electron density revealed that van der Waals dimers of physisorbed O2 locate in the middle of nanochannels and form a one-dimensional ladder structure aligned to the host channel structure. The observed O-O stretching Raman band and magnetic susceptibilities are characteristic of the confined O2 molecules in one-dimensional nanochannels of CPL-1 (coordination polymer 1 with pillared layer structure).  相似文献   
274.
Beet necrotic yellow vein virus (BNYVV) is the causal agent of rhizomania, the most serious sugar beet disease worldwide. Since the first finding in Japan in 1969, BNYVV became widespread throughout Hokkaido in a few decades and led to the introduction of Rz1-resistant sugar beet cultivars in the 1990s. Here, we report the historical progress of the BNYVV epidemic in Hokkaido from 1969 to 2019. Previous analysis on samples from 1991 showed that BNYVV isolates were classified into three strains (named O, D, and T) based on the RNA3-encoded p25 gene. The O-type viruses were widely detected in Hokkaido, while the D- and T-type viruses were detected in limited areas. The RNA5, encoding the p26 gene, was initially contained in some D- and O-type isolates but not in any T-type isolates. Interestingly, recent sample analysis revealed that RNA5-containing T-type viruses, seemingly more virulent than the other two strains, were widely detected in Hokkaido. Additionally, a small group of virus isolates harbouring a new p25 gene (named C) was found in limited areas. These results suggest that the T-type viruses, which accompanied RNA5, have been preferentially spread from a limited area to other districts over the last few decades and that this spread might be strongly associated with the recent introduction of Rz1-resistant sugar beet cultivars. BNYVV-positive samples also contained mainly beet soil-borne virus and traces of beet virus Q, both of which are the first to be recorded in Japan.  相似文献   
275.
ABSTRACT:   The auditory brainstem response (ABR) of fishes is commonly measured by bringing the heads of the fishes out of the water in a small tank. However, this method is inapplicable to experiments for large fishes that are economically important in large spaces such as the sea or in a large tank. This paper describes a method of recording, the ABR for fishes in water, without exposing the fish heads to air, by using a waterproof, insulated electrode. To evaluate the effectiveness of this method, the goldfish Carassius auratus was investigated, and the ABR waveform and auditory thresholds measured in water were compared with those measured on the surface. Both ABR waveforms and auditory thresholds showed similar trends between the two methods. The underwater ABR method is useful to measure the auditory thresholds of larger fish in natural or on-site environments such as the sea, net enclosures and large aquaria in which precise positioning of the fish is not possible. However, more improvement is needed to apply this method to large fishes.  相似文献   
276.
ABSTRACT Tomato wilt, caused by the soilborne fungus Fusarium oxysporum f. sp. lycopersici, is effectively controlled by a foliar spray of validamycin A (VMA) or validoxylamine A (VAA) (>/=10 mug/ml); however, neither VMA nor VAA is antifungal in vitro. In pot tests, the effect of a foliar application of VMA or VAA at 100 mug/ml lasted for 64 days. Plants sprayed with VMA or VAA accumulated salicylic acid and had elevated expression of the systemic acquired resistance (SAR) marker genes P4 (PR-1), Tag (PR-2), and NP24 (PR-5). Foliar spray of VMA also controlled late blight and powdery mildew of tomato. The disease control by VMA and VAA lasted up to 64 days after treatment, was broad spectrum, and induced the expression of PR genes, all essential indicators of SAR, suggesting that VMA and VAA are plant activators. The foliar application of plant activators is a novel control method for soilborne diseases and may provide an economically feasible alternative to soil fumigants such as methyl bromide.  相似文献   
277.
The immune system in juvenile calves is immature, so calves are susceptible to several diarrheal and respiratory diseases. Oral administration of lactic acid bacteria (LAB) is known to improve the growth performance and prevent diarrheal and respiratory diseases by stimulating the immune system in juvenile calves. Most of the immunostimulation by LAB is achieved by their cell wall components, and therefore we evaluated the immunostimulation of the cell preparation of Enterococcus faecalis strain EC-12 (EC-12) in juvenile calves in a clinical field. Twenty-nine 1-week old calves were used. Fourteen calves were administered 0.2% (w/w) of an EC-12 preparation that supplemented a milk replacer, and other calves were not supplemented. Feces and serum was collected at day 0, 7 and 49 after the administration to measure the IgA and IgG concentration. The fecal IgA concentration was increased by EC-12 administration at day 49, and the serum IgA concentration was also increased at day 7. These results suggested that oral administration of EC-12 in juvenile calves might have an immunostimulatory effect and provide earlier recovery of IgA levels in mucosal immunity.  相似文献   
278.
Cultivated rice (Oryza sativa L.) is derived from Asian wild rice (Oryza rufipogon Griff). Vietnamese local varieties and wild natural populations in Vietnam and Myanmar were examined to evaluate the levels of genetic variation in cultivated and wild rice. In total, 222 Vietnamese local varieties were analyzed with ten microsatellite markers. Using marker genotype and gene diversity data, the local varieties were differentiated based on geographical distribution, cropping season, and human preference. A total of 976 wild plants were collected at six natural sites of wild populations (three each in Myanmar and Vietnam), and the degrees of variation among populations were analyzed with five microsatellite markers. Phylogenetic analyses revealed wide genetic differentiation among wild populations. The diversity values detected in a single wild population in Vietnam were higher than those in whole Vietnamese local varieties. These results indicate that wild rice has much greater genetic variation than cultivated rice.  相似文献   
279.
OBJECTIVE: To determine the effects of continuous low-dose infusion of lipopolysaccharide (LPS) on the expression of E-selectin and intercellular adhesion molecule-1 (ICAM-1) mRNA and neutrophil accumulation in the lungs, liver, spleen, small intestine, and pancreas in dogs. ANIMALS: 11 healthy adult Beagles. PROCEDURE: Dogs received a continuous infusion of a low dose (10 microg/kg/h, i.v.) of LPS (Escherichia coli 055:B5) or saline (0.9% NaCI) solution (20 mL/kg/h, i.v.) for 8 hours. Activity levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (1L-6) and the number of WBCs in circulation were examined before and 1, 2, 4, and 8 hours after the onset of LPS infusion. Expression of E-selectin and ICAM-1 mRNA and the number of neutrophils in each tissue were examined. RESULTS: After the onset of LPS infusion, serum TNF-alpha and IL-1beta activities transiently increased. Thereafter, IL-6 activity increased, and high IL-6 activity was maintained throughout the experiment. In dogs in the LPS group, expression of E-selectin mRNA increased only in the lungs, and expression of ICAM-1 mRNA increased in the lungs and liver; the number of neutrophils in the tissue increased in the lungs and liver. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that expression of E-selectin and ICAM-1 mRNA increased during sepsis, particularly in the lungs and liver, and that this increase was associated with neutrophil accumulation. Hence, inhibiting the activation of endothelial cells in the lung and liver may decrease organ damage caused by accumulated neutrophils and help regulate multiple-organ dysfunction.  相似文献   
280.
Changes in immune factors expressed by milk somatic cells from Holstein cows with hypocalcemia after calving were investigated in this study. Fourteen multiparous Holstein cows after their 3rd or 4th calving in one farm were used. The cows were divided into 2 groups: 7 cows needing treatment due to onset of hypocalcemia (hypocalcemia group; age = 5.53 ± 0.27 years, parity = 3.14 ± 0.14) and 7 cows without health problems (control group; age = 5.88 ± 0.31 years, parity = 3.57 ± 0.26). Milk samples were collected aseptically using a cannula and mRNA of immune factors expressed by milk somatic cells were analyzed. Milk samples (50 mL) were collected from the right rear mammary gland of cows before milking at day 1 and weeks 1, 2, 4, and 8 after calving. All milk samples showed a negative reaction to the California Mastitis Test. Levels of relative interleukin (IL)-6 and cathelicidin in the hypocalcemia group were lower than those in the control group in weeks 1 to 8. A significant difference in relative IL-6 levels was found in week 4 (P < 0.05). These results suggest that levels of IL-6 expressed by milk somatic cells may be affected by hypocalcemia in dairy cows.  相似文献   
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