• Journal of Veterinary Science
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• v.22 no.3
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• pp.36.1-36.12
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• 2021

Background: Mouse hepatitis virus (MHV) A59 is a highly infectious pathogen and starts in the respiratory tract and progresses to systemic infection in laboratory mice. The complement system is an important part of the host immune response to viral infection. It is not clear the role of the classical complement pathway in MHV infection. Objectives: The purpose of this study was to determine the importance of the classical pathway in coronavirus pathogenesis by comparing C1qa KO mice and wild-type mice. Methods: We generated a C1qa KO mouse using CRISPR/Cas9 technology and compared the susceptibility to MHV A59 infection between C1qa KO and wild-type mice. Histopathological and immunohistochemical changes, viral loads, and chemokine expressions in both mice were measured. Results: MHV A59-infected C1qa KO mice showed severe histopathological changes, such as hepatocellular necrosis and interstitial pneumonia, compared to MHV A59-infected wild-type mice. Virus copy numbers in the olfactory bulb, liver, and lungs of C1qa KO mice were significantly higher than those of wild-type mice. The increase in viral copy numbers in C1qa KO mice was consistent with the histopathologic changes in organs. These results indicate that C1qa deficiency enhances susceptibility to MHV A59 systemic infection in mice. In addition, this enhanced susceptibility effect is associated with dramatic elevations in spleen IFN-γ, MIP-1 α, and MCP-1 in C1qa KO mice. Conclusions: These data suggest that C1qa deficiency enhances susceptibility to MHV A59 systemic infection, and activation of the classical complement pathway may be important for protecting the host against MHV A59 infection.

• Journal of Pharmacopuncture
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• v.26 no.4
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• pp.348-356
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• 2023

Objectives: Neuralgia-pharmacopuncture (NP) was recently developed as a water-soluble type of pharmacopuncture inspired by CS (care special pain)-pharmacopuncture. I aimed to evaluate the toxic response and approximate lethal dose of when NP when administered intramuscularly to Sprague Dawley rats. Methods: The experimental group was divided into the NP test substance group and the saline control group and administered at a dose of 1.0 mL/animal to the posterior thigh muscles on both sides using a 1 mL syringe; each group consisted of five males and five females. Each rat was monitored for clinical signs and changes in body weight for 14 days after a single intramuscular injection. After completing observation, necropsy findings and localized tolerance at the injection site were assessed via gross necropsy and histopathological examination. Results: No deaths occurred in the NP or control group, regardless of sex. During the observation period, no changes (such as general symptoms, weight change, or visual observation results at the time of autopsy) were judged to be due to the test substance. Histopathological examination showed no changes at the administration site judged to be caused by the test substance in either the male or female test substance administration groups. In addition, mononuclear cell infiltration of the outer membrane of the femoris muscle at the administration site was observed at the same frequency and extent in the control and NP groups, and was judged to be caused by physical stimulation by the injection needle; therefore, it had no toxicological significance. Conclusion: Based on the above results, the approximate lethal dose for a single intramuscular administration of the test substance NP in Sprague-Dawley rats was judged to be > 1.0 mL/animal, and there were no findings that were judged to be due to the test substance at the administration site.

• Journal of fish pathology
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• v.18 no.3
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• pp.247-258
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• 2005

To understand responses of bivalve tissues to various injurious agents, histopathological observation was done in the Manila clam, Ruditapes hilippinarum, during 240 hours after an intramuscular injection of N-methyl-N-nitro-N-nitrosoguanidine (MNNG). Some histopathological changes were observed with the epithelia of stomach, midgut, hindgut, digestive diverticula and gonads after injecting MNNG. The earliest degenerative changes were recognized in the epithelium of midgut 12 hours after the injection. Partial or complete, epithelial destruction was constantly accompanied by the massive infiltration of a mononuclear, necrotic cell group including hemocytes. At 144 hours later, gonads showed the necrotic desquamation of their germinal epithelia. Nearly all of the infiltrated cells within the destructive epithelium were suggested to be hemocytes, from the binding property with a hemocyte-specific lectin, Ricinus communis (RCA-1). From these results it was concluded that the epithelium of digestive system is vulnerable to parenteral MNNG and hemocytes might be deeply involved in this MNNG-induced destruction of the digestive epithelium.

• Korean Journal of Veterinary Research
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• v.25 no.2
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• pp.103-112
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• 1985

A total of 1-0 colostrum-deprived pigs (1 or 2-day-old) and 6 pigs (35-day-old), which had been raised by natural maternal nursing, were used to study the pathogenicity of the porcine enteroviruses by the intracerebral and intramuscular routes of inoculation, which the enterovirus were isolated from the diseased pigs in Korea. The porcine enteroviruses produced an identical polioencephalomyelitis in colostrum-deprived pigs and 35-day-old pigs, which manifested clinical signs and histopathological changes. Clinically it was characterized by incoordination, rise in rectal temperature, ataxia, flaccid paralysis in all the experimental groups. Histopathologically, the lesions were present in both grey and white matter at all levels of central nervous system, though usually more severe in the grey matter. These changes were characterized by meningeal infiltration, degeneration of nerve cells, neuronophagia, diffuse and focal gliosis, glial nodules and perivascular lymphocytic infiltrations. Ganglionitis of the dorsal root ganglia was frequently observed. On the basis of the clinical and histopathological changes mentioned above, it was concluded that porcine enteroviruses isolated in Korea were pathogenic strains which could produce polioencephalomyelitis in pigs. The most severe Jisease was prcduced by the inoculation of both enterovirus and hog cholera vaccine in the 35-day-old pigs at a time when colostral immunity presumably was low. The porcine enterovirus infections seemed to be associated with certain stress factor such as hog cholera vaccine in or immediately following the weanling period.

• Biomolecules & Therapeutics
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• v.16 no.2
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• pp.137-140
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• 2008

The effects of Picrorrhiza Rhizoma (PR) aqueous extracts were observed on xylene-induced acute inflammation. The xylene was topically applied 60 min after administration of 500, 250 and 125 mg/kg of PR extracts, and all animals were sacrificed 2 hrs after xylene application. The changes on ear weights, histolopathological analyses of ear were evaluated as compared with indomethacin and dexamethasone 15 mg/kg treated groups - well known anti-inflammatory agents. Xylene application resulted in marked increases in induced ear weights as compared with intact control ear. Severe vasodilation, edematous changes of ear skin and increase in the thickness of the ear tissues as acute inflammation were detected in xylene-treated control ears at histopathological observation. However, these xylene-induced acute inflammatory changes were dosedependently decreased by oral treatment of PR extracts. Therefore, it is concluded that PR extracts has favorable anti-inflammatory effects on xylene-applicated acute ear inflamed mice.

• The Journal of Dong Guk Oriental Medicine
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• v.11
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• pp.66-73
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• 2008

Objectives: The study was designed to evaluate the single dose toxicity of modified Bo-yang-Hwan-o-Tang (mBHT) in Sprague-Dawley (SD) rats. Methods: The mBHT was once administrated orally to both sexes of rats at dose 2,000 mg/kg body weight which are the recommended maximum limit dose for acute toxicity. We recorded clinical signs of toxicity, body weight, gross and histological changes in target organs for all rats. Results: Neither significant changes of body weight not death was observed during the observation period in mBHT-administrated rats. Neither significant toxic signs not histopathological changes were shown during the observation period. There were not observed significant gross abnormality between the control and mBHT-administrated rats. Conclusions: These results indicated that the toxicity of mBHT is greater than 2,000 mg/kg body weight in SD rats.

• Advances in Traditional Medicine
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• v.7 no.3
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• pp.304-310
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• 2007

Monocrotophos was administered orally to adult male albino mice at dose level of 3.0 mg/kg body weight/day/mice for 50 days. The treatment has found to affect spermatogenesis as well as the endocrine functions of the testis as indicated by gravimetric, histopathological and biochemical changes. The treatment has caused degenerative changes in the seminiferous tubules and Leydig cells of the testis and regression of the epididymis, seminal vesicle, vas deferens, prostate, Cowper's gland and levator ani. Similarly, cauda epididymal sperm count and sperm motility have shown significant reduction. There was a significant reduction in the protein, glycogen, sialic acid, acid and alkaline phosphatase and increase in cholesterol in the testis of monocrotophos treated mice compared with the control. The causative factors for these changes due to monocrotophos administration were discussed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.203-204
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• 2003

Ammonia in aquaculture system may lead to suppression of fish growth, sublethal histopathological changes, and even death thus ammonia is considered toxic to fish. Tricking filter and submerged filter have many advantages include: low construction cost, easy management and maintenance, and well adaptation to different water and waste loading rates. (omitted)

• YAKHAK HOEJI
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• v.43 no.3
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• pp.358-368
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• 1999

Subacute toxicity study was performed in Sprague-Dawley rats after daily dermal administration of Sangmosu (0.2, 1.0 and 5.0 g/kg) for one month. There were no clinical signs and pathological changes compared with control group. Bodyweights were not significantly changed between control and Sangmosu treatment groups. In histopathological examinations, there were some pneumonia in lung tissues at all groups of Sangmosu treatment including control, but it was not considered to be caused by Sangmosu. These results suggest that Sangmosu does not induce any significant subacute dermal toxicities in Sprague-Dawley rats.

• Toxicological Research
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• v.21 no.3
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• pp.227-234
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• 2005