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31.
Using macrophage scavenger receptor-A knockout (SRKO) mice, we examined the role of macrophage class A scavenger receptors (MRS-A) on the immune response and acquisition of host resistance against repeated infestation with Haemaphysalis longicornis. Except for one batch of nymphs that infested one of the SRKO (SR-/-) mice and showed no appreciable reduction in body weight, all the other groups of nymphs manifested significant decrease in body weight. Both SR-/- and wild type (SR+/+) mice showed a sustained increase in anti-tick antibody titers, but SR+/+ mice showed significantly higher titers. The IFN-gamma assayed in SR-/- mouse immune sera was substantially less compared with that in SR+/+ mice. Immune sera from SR-/- and SR+/+ mice recognized the 51 and 44 kDa, and 44 kDa proteins, respectively, of the salivary gland antigen. The difference in the level of anti-tick resistance manifested by both groups of mice may be influenced by less efficient trapping and processing of tick antigens by macrophages in mice lacking for the macrophage scavenger receptors, and consequently affected the cascade of Th1 and Th2 responses. We have thus obtained valuable data that strongly infer the role of MSR-A in enhancing host defense against repeated infestation with H. longicornis.  相似文献   
32.
Indian dwarf wheat (Triticum aestivum L. ssp. sphaerococcum (Perc.) Mac Key, synonym: T. sphaerococcum Perc.) is endemic to southern Pakistan and northwestern India. It was one of the main winter crops grown by ancient Indian cultures. However, it disappeared from the record during the early twentieth century, especially after the Green Revolution brought modern wheat varieties into India and Pakistan. Whether or not Indian dwarf wheat is presently cultivated has been unclear. Here we report on the rediscovery of the cultivation of this wheat in northern Karnataka and southern Maharashtra in India. Molecular genetic analysis of the chloroplast DNA of the two specimens collected at location 3 revealed that both samples have a unique haplotype that is specific to Indian dwarf wheat. We found this wheat at three locations in 2010, but at only one of the three locations in 2011. Therefore, the future survival of this subspecies is uncertain. Further ethnobotanical research is urgently needed to conserve this unique genetic resource for the future.  相似文献   
33.
Melatonin has been reported to improve the in vitro development of embryos in some species. This study was conducted to investigate the effect of melatonin supplementation during in vitro maturation (IVM) and development culture on the development and quality of porcine embryos. In the first experiment, when the in vitro fertilized embryos were cultured with different concentrations of melatonin (0, 10, 25 and 50 ng/ml) for 8 days, the blastocyst formation rate of embryos cultured with 25 ng/ml melatonin (10.7%) was significantly increased (p < 0.05) compared to the control embryos cultured without melatonin (4.2%). The proportion of DNA‐fragmented nuclei in blastocysts derived from embryos cultured with 50 ng/ml melatonin was significantly lower (p < 0.05) than that of embryos cultured without melatonin (2.1% vs 7.2%). In the second experiment, when oocytes were cultured in the maturation medium supplemented with different concentrations of melatonin (0, 10, 25 and 50 ng/ml), fertilized and then cultured with 25 ng/ml melatonin for 8 days, there were no significant differences in the rates of cleavage and blastocyst formation among the groups. However, the proportions (2.7–5.4%) of DNA‐fragmented nuclei in blastocysts derived from oocytes matured with melatonin were significantly decreased (p < 0.05) compared to those (8.9%) from oocytes matured without melatonin, irrespective of the concentration of melatonin. Our results suggest that supplementation of the culture media with melatonin (25 ng/ml) during IVM and development has beneficial effects on the developmental competence and quality of porcine embryos.  相似文献   
34.
In this study, two following experiments were performed to improve post-thaw motility and viability of frozen-thawed ram spermatozoa. We examined i) the effects of different concentrations of bovine serum albumin (0, 0.3, 1, 5, 10 and 15% BSA) in semen diluents lacking egg yolk and ii) the effects of four semen diluents, fructose (F: control) and trehalose (T) in semen diluents containing egg yolk, 15% BSA in semen diluents without egg yolk (BSA), and modified phosphate buffered saline (m-PBS). Frozen-thawed spermatozoa were examined for progressive sperm motility, viability, morphological abnormality, sperm tail swelling test, and sperm acrosome integrity. In Experiment 1, the rates of sperm motility immediately after thawing (0 h) were significantly (P<0.05) higher in the 10 and 15% BSA groups (55.0 +/- 2.9 and 58.3 +/- 6.7%, respectively) than in the positive control (F) group (41.7 +/- 4.4%). The rate of sperm viability in the negative control (0% BSA) group (80.2 +/- 3.3%) was significantly (P<0.05) lower than in the positive control (F) group (89.8 +/- 1.5%), but when compared with the F group, no significant differences were found among the 0.3, 1, 5, 10 and 15% BSA groups at 0 h. The rates of sperm morphological abnormality of the 10 and 15% BSA groups (6.5 +/- 1.3 and 6.3 +/- 1.1%, respectively) were significantly (P<0.05) lower at 0 h than that in the 1% BSA group (16.3 +/- 5.2%). In Experiment 2, T addition improved (P<0.05) the post-thaw motility compared with the F and BSA groups. Furthermore, at 3 and 6 h, the post-thaw motility of the T group (36.3 +/- 2.4 and 25.0 +/- 2.0%, respectively) was significantly (P<0.05) higher than in the BSA (26.3 +/- 2.4 and 18.8 +/- 1.3%, respectively) and F (28.8 +/- 3.8 and 18.8 +/- 2.4%, respectively) groups. The post-thaw sperm motility and viability in the m-PBS group were significantly (P<0.05) lower than those of the control (F), T, and BSA groups throughout all observation points. These results indicate that 10 and 15% BSA can be substituted for egg-yolk for ram semen diluent and that the addition of trehalose enhances motility and viability of ram spermatozoa after freezing and thawing.  相似文献   
35.
A dog presented with hematuria, and two small polypoid masses were detected in the urinary bladder. Histopathologically, the masses were located in the mucosal or submucosal layer. That tissue consisted of a random proliferation of spindle-shaped, round and pleomorphic cells with single or multiple large atypical nuclei and abundant cytoplasm, and eosinophil infiltration. These large cells were confirmed by immunohistochemical staining as fibroblasts, myofibroblasts and macrophages. Mitotic figure was rarely seen. These masses were diagnosed as eosinophilic polypoid cystitis with pseudosarcomatous proliferative tissue, since they consisted of a wide variety of cells and showed low growth activity.  相似文献   
36.

Background

Definitive diagnosis of histiocytic sarcoma (HS) in dogs is relatively difficult by conventional histopathological examination because objective features of HS are not well defined.

Hypothesis

Quantitative analysis of mRNA expression of selected cellular surface antigens (SAs) specific to HS in dogs can facilitate objective and rapid diagnosis.

Animals

Dogs with HS (n = 30) and dogs without HS (n = 36), including those with other forms of lymphoma (n = 4), inflammatory diseases (n = 6), and other malignant neoplasias (n = 26).

Methods

Retrospective clinical observational study. Specimens were collected by excisional biopsy, needle core biopsy, or fine needle aspiration. To determine HS detection efficacy, mRNA expression levels of selected SAs specific to HS in dogs, including MHC class IIα, CD11b, CD11c, and CD86, were quantitatively analyzed using real‐time quantitative polymerase chain reaction.

Results

Each SA mRNA expression level was significantly higher in HS dogs than in non‐HS dogs (= .0082). Cutoff values for discriminating between HS and non‐HS dogs based on these expression levels were calculated on the basis of receiver‐operating characteristic analysis. Accuracy of the cutoff values, including MHC class IIα, CD11b, CD11c, and CD86, was 87.9, 86.4, 86.4, and 84.8%, respectively.

Conclusions and Clinical Importance

Our results suggest that quantitative analysis of mRNA expression of the selected SAs could be an adjunctive diagnostic technique with high diagnostic accuracy for HS in dogs. Substantial investigation is required for exclusion of diseases with similar cell types of origin to lymphoma.  相似文献   
37.
The present study was conducted to investigate whether a portable CO2 incubator was effective for in vitro maturation (IVM) of bovine, porcine and minke whale oocytes, and the effect of maturation media supplemented with different hormones; porcine follicle stimulating hormone (pFSH), estradiol-17beta (E2), or pregnant mare's serum gonadotropin (PMSG): human chorionic gonadotropin (hCG) for minke whale immature oocytes was also examined. In vitro maturation rates of bovine and porcine oocytes cultured in the portable CO2 incubator were not significantly different from the standard CO2 incubator. In minke whale IVM culture using the portable incubator, the maximum expansion of cumulus mass was observed by pFSH/E2 and PMSG/hCG at the end of IVM culture. Moreover, the IVM culture period was shortened to 28-30 h from 96-120 h previously reported. The proportion of matured oocytes cultured in the medium supplemented with pFSH/E2 (26.7%) was significantly higher (P<0.05) than that with PMSG/hCG (6.9%). The present study indicates that a portable CO2 incubator is a useful device for minke whale IVM culture on a research base ship, and the addition of pFSH/E2 into an IVM medium enhanced cumulus expansion and the proportion of minke whale matured oocytes.  相似文献   
38.
Middle ear cholesteatoma is caused by the formation of epidermoid cysts that result in distention and enlargement of the tympanic bulla with subsequent destruction of surrounding tissues. We report treatment of middle ear cholesteatoma in 2 dogs, via an oral surgical approach. Abnormal tympanic bulla contents and the wall compressing the pharynx were successfully removed in both cases. Computed tomography imaging, surgical findings, and histopathology results were consistent with middle ear cholesteatoma in both cases. The outcomes in both cases suggest that an oral surgical approach may be an alternative treatment for middle ear cholesteatoma in dogs.Key clinical message:Despite the limited number of cases described herein, our report indicates that the direct oral approach for canine cholesteatoma may be and alternative approach.  相似文献   
39.
The production and partial characterization of bacteriocin‐like substances (BLSs) produced by bacteria isolated from cow manure compost were investigated. Eight BLS producers, which exhibited inhibitory activity against pathogenic bacteria, were isolated from cow manure compost at different stages of the composting process. The pile temperature ranged from 9.1°C to 73.2°C. The BLSs showed thermostability, but the BLS producers were not thermostable except for the H1 producer. Thermophilic Bacillus licheniformis H1 was further characterized. The culture supernatant of B. licheniformis H1 exhibited antagonistic activity against various species of Gram‐positive bacteria such as Listeria monocytogenes ATCC19111 but not against Gram‐negative bacteria except Pseudomonas fluorescens ATCC11251. Inactivation of bacteriocin‐like activity by α‐chymotrypsin, trypsin, and papain was highly significant (P < 0.001). The BLS was found to be stable under a pH range from 3 to 9 and at temperatures up to 75°C for 60 min, but it lost activity after being autoclaved at 121°C for 15 min. The optimum production of BLS by B. licheniformis H1 was obtained at a temperature of 55°C. Sodium dodecyl sulfate – polyacrylamide electrophoresis analysis of concentrated partially purified supernatants collected after resting the bacterial cells at 55°C revealed a bacteriocin‐like protein with a molecular mass of approximately 3.5 kDa. This study is the first report of a BLS from thermophilic B. licheniformis with an animal compost origin.  相似文献   
40.
Three hyperimmune dogs were injected intramuscularly with canine wild rabies virus. The dogs showed no clinical evidence of rabies. Intramuscular injection of the wild rabies virus in susceptible puppies induced fulminating disease and mortality in 14 to 16 days. Investigation of the serum proteins of the hyperimmune dogs by a paper electrophoresis technique revealed conspicuous changes in the beta and gamma protein bands.  相似文献   
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