OBJECTIVETo investigate the ultrastructural changes of the extraintestinal organs of newborn mice with human retrovirus (RV) infection to probe into the mechanism and clinical diagnose and therapy of extraintestinal RV infection.

METHODSHuman RV was inoculated into the abdominal cavity of the newborn mice, and the ultrastructural changes of the heart, lung, livers, and kidneys of the infected and control mice were observed by transmission electron microscope.

RESULTSThe mice with intraabdominal RV injection showed pathological changes of the cells in the small intestinal villus, liver, and kidneys. Shortened small intestinal villus, nuclear membrane disorganization, massive vacuolization, mitochondrial swelling and rough endoplasmic reticulum dilation were observed in the cells of the small intestinal. In the liver of the mice, marked mitochondrial swelling and agglutination, cell nucleus pyknosis or collapse, presence of numerous lipid droplets and vacuoles were seen in the liver cells, with lymphocyte and plasmacyte infiltration. Obvious dilatation and shedding of the microvillus were seen in cholangioles. The mitochondria of the proximal convoluted renal tubule showed mild swelling, but the cells in the heart and lung did not display obvious changes.

CONCLUSIONThe small intestinal villi were highly susceptible to RV infection, and systemic spread of human RV may cause damage of various extraintestinal organs especially the liver, which can also be susceptible to RV.

Animals ; Animals, Newborn ; Female ; Intestine, Small ; ultrastructure ; virology ; Kidney ; ultrastructure ; virology ; Liver ; ultrastructure ; virology ; Lung ; ultrastructure ; virology ; Male ; Mice ; Microscopy, Electron, Transmission ; Rotavirus Infections ; pathology ; virology

OBJECTIVETo know the genotype and subtype of hantavirus (HV) carried by host animals in HFRS natural epidemic area of Hebei province.

METHODSAccording to the conservative sequence of 76-118 and R22 strains, specific primers were designed. RT-nested PCR was used to amplify partial M segments from the positive rat lungs screened by IFA. Agarose gel electrophoresis was used to identify the types. Nucleotides were assayed from partial products after purification and reclaim. Gene analysis was carried on with DNAStar package.

RESULTS32 specimens, which were positive screened by IFA, were amplified the specific segment (418bp) and all belonged to type SEO. Sequencing results of 10 partial segments indicated that G2 segment had little variability and nucleotide homology reached to 98.0%-100.0%. Comparing with the R22 and 76-118 strains, homology was 93.3%-94.3% and 67.7%-69.0% respectively.

CONCLUSIONAccording to G2 segment, SEO was the major type in Hebei HFRS natural epidemic area and S3 was the major subtype. HV which belonged to the same subtype had high homology and genetic materials were correspondingly stable. Different rats could carry the same subtype of HV.

Animals ; Animals, Wild ; virology ; Disease Reservoirs ; virology ; Genotype ; Hantavirus ; classification ; genetics ; isolation & purification ; Lung ; virology ; Molecular Sequence Data ; Phylogeny ; RNA, Viral ; genetics ; Rats ; virology ; Sequence Analysis, DNA

The bovine leukemia virus (BLV) is the causative agent of enzootic bovine leucosis. This study investigated the presence of the BLV in leukemia (179 acute lymphoblastic leukemia, 292 acute myeloid leukemia and 46 chronic myelogenous leukemia cases) and 162 lung cancer patients (139 adenocarcinoma, 23 squamous cell carcinoma) to determine if the BLV is a causative organism of leukemia and lung cancer in Koreans. A BLV infection was confirmed in human cells by PCR using a BLV-8 primer combination. All 517 cases of human leukemia and 162 lung cancer were negative for a PCR of the BLV proviral DNA. In conclusion, although meat has been imported from BLV endemic areas, the BLV infection does not appear to be the cause of human leukemia or lung cancer in Koreans. These results can be used as a control for further studies on the BLV in Koreans.
Acute Disease ; Adenocarcinoma/virology ; Cell Line ; DNA, Viral/*genetics/isolation & purification ; Humans ; Korea ; Leukemia/*virology ; Leukemia Virus, Bovine/*genetics ; Leukemia, Lymphocytic, Acute/virology ; Leukemia, Myeloid/virology ; Leukemia, Myeloid, Chronic/virology ; Lung Neoplasms/*virology ; Polymerase Chain Reaction/methods ; Proviruses/*genetics

The objectives of the present study were to evaluate the anatomic localization of porcine reproductive and respiratory syndrome virus (PRRSV) in naturally infected pigs and to determine whether oral fluid could be used to detect the virus in infected animals. Two sows, seven 2-month-old grower pigs, and 70 6-month-old gilts were included in this study. PRRSV in sera and oral fluid were identified by nested reverse transcription PCR (nRT-PCR) while lung, tonsil, and tissue associated with oral cavity were subjected to nRT-PCR, immunohistochemistry, and in situ hybridization. In sows, PRRSV was identified in oral fluid and tonsils. PRRSV was also detected in oral fluid, tonsils, salivary glands, oral mucosa, and lungs of all seven grower pigs. However, viremia was observed in only two grower pigs. Double staining revealed that PRRSV was distributed in macrophages within and adjacent to the tonsillar crypt epithelium. In gilts, the North American type PRRSV field strain was detected 3 to 8 weeks after introducing these animals onto the farm. These results confirm previous findings that PRRSV primarily replicates in tonsils and is then shed into oral fluid. Therefore, oral fluid sampling may be effective for the surveillance of PRRSV in breeding herds.
Animals ; Female ; In Situ Hybridization/veterinary ; Lung/virology ; Male ; Palatine Tonsil/virology ; Polymerase Chain Reaction/veterinary ; Porcine Reproductive and Respiratory Syndrome/*virology ; Porcine respiratory and reproductive syndrome virus/*physiology ; Saliva/*virology ; Salivary Glands/virology ; Swine/virology ; Virus Replication/physiology

OBJECTIVETo document ultrastructural changes of brain, spinal cord, skeletal muscle, jejunum and lung of EV71 infection mouse model, and to explore the myotropism and pathogenesis of EV71 in nervous system.

METHODSTen-day-old suckling mice were infected with EV71 strain via the intraperitoneal route. Mice with paralysis were scarified on day 4 post infection and the brain, spinal cord, skeletal muscle, jejunum and lung were sampled for transmission electron microscopy and light microscopy.

RESULTSLesions in brain were generally mild with inner chamber swelling in some of mitochondria. Myelin sheaths of medullated fibers were split with vacuolated changes. The Nissl bodies in anterior motor neurons disappeared along with mitochondria swelling, rough endoplasmic reticulum swelling and degranulation. Cytoplasm of anterior motor neurons showed cribriform appearance accompanied by neuronophagia. The bands of skeletal muscle in the infected group disappeared with degeneration and karyopyknosis in myocytes, in addition to mitochondrial swelling. Microvilli of epithelium in jejunum became loosely arranged along with formation of spiral medullary sheath structure and mitochondria swelling. Interstitial pneumonia was observed in lungs with type II pneumocyte proliferation and evacuation of the multilamellar bodies.

CONCLUSIONSEV71 infection causes severe myositis in the mouse model suggesting a strong myotropism of EV71 virus. The presence of lesions of various degrees in central nervous system and changes in anterior motor neurons may be associated with limb paralysis.

Animals ; Brain ; ultrastructure ; virology ; Disease Models, Animal ; Enterovirus A, Human ; Enterovirus Infections ; pathology ; virology ; Jejunum ; ultrastructure ; virology ; Lung ; ultrastructure ; virology ; Mice ; Mice, Inbred BALB C ; Microscopy, Electron, Transmission ; Muscle, Skeletal ; ultrastructure ; virology ; Spinal Cord ; ultrastructure ; virology

The tissue distribution and cellular localization of viral antigens in three cattle with persistent bovine viral diarrhea virus (BVDV) infection was studied. In three cases, necropsy findings of oral ulcers, abmasal ulcers and necrosis of Peyer's patches were suspected have been caused by BVDV infection. Non-cytopathic BVDV was isolated from a tissue pool of liver, kidneys and spleen. Immunohistochemical detection of BVDV showed that BVDV antigens were detected in both epithelial and nonepithelial cells in all examined organs, including the gastrointestinal tract, liver, pancreas, lung, lymphatic organs (spleen, lymph nodes), adrenal gland, ovary, uterus, and the mammary gland. These findings support the hypothesis that animals with persistent BVDV infection spread BVDV through all routes, and that infertility in BVDV infection is associated with the infection of BVDV in the ovaries and uteri.
Adrenal Glands/pathology/virology ; Animals ; Antigens, Viral/*isolation & purification ; Bovine Virus Diarrhea-Mucosal Disease/pathology/physiopathology/*virology ; Cattle ; Diarrhea Viruses, Bovine Viral/immunology/*isolation & purification ; Digestive System/pathology/virology ; Female ; Immunohistochemistry/veterinary ; Infertility, Female/virology ; Kidney/pathology/virology ; Lung/pathology/virology ; Lymphatic System/pathology/virology ; Mammary Glands, Animal/virology ; Ovary/pathology/virology ; Uterus/pathology/virology

In order to investigate the human cytomegalovirus (HCMV) infection, the mouse cytomegalovirus (MCMV) infected mice were experimentally studied. 6 to 8 week old female BALB/C mice with immunosuppression were selected to undergo the MCMV inoculations: intracranial inoculation and peritoneal inoculation. MCMV of the infected mice in various organs and tissues were detected by using beta-gal staining and in situ nucleic acid hybridization assay. The pathological changes were observed in HE staining paraffin-embedded sections. It was found that all the MCMV infected mice showed the retardation of growth and development, and feather looseness. Both intracranial inoculation of 10(4) PFU viruses or peritoneal inoculation of 10(6) PFU viruses resulted in the pathological changes, to some extent, of various organs and tissues in the mice. The pathological changes in liver were consistent with the amount of beta-gal staining positive cells, indicating the liver lesions were mainly caused by viral proliferation. It was also found that the viruses in the immunosuppressed mice subjected to intracranial inoculation could spread to whole body organs, while the viruses in the immunosuppressed mice subjected to intrapeitoneal inoculation couldn't spread to the brain, suggesting blood-brain barrier could prevent the virus from spreading to the brain.
Blood-Brain Barrier ; Brain/pathology ; Brain/virology ; Disease Models, Animal ; *Herpesviridae Infections/pathology ; *Herpesviridae Infections/virology ; Immunocompromised Host ; Liver/pathology ; Liver/virology ; Lung/pathology ; Lung/virology ; Mice, Inbred BALB C ; *Muromegalovirus

BACKGROUNDChina is the most severe endemic area of hemorrhagic fever with renal syndrome (HFRS) in the world with 30,000-50,000 cases reported annually, which accounts for more than 90% of total number of cases worldwide. The incidence rate of the syndrome in Shandong Province is one of the highest in China, which has ever reached 50 per 100,000 persons per year. However, the molecular characteristics of hantaviruses (HV) epidemic in Shandong Province remain unclear. Therefore it is useful to clarify nucleotide sequence and phylogenetic characteristics of HV isolated in Shandong Province in order to provide better advices to control and prevent HFRS.

METHODSRNAs were extracted from sera of clinically diagnosed patients and positive rodent lungs that were detected by indirect immunofluorescent assay (IFA). Partial M segments of HV were amplified from the RNAs with reverse transcription nested polymerase chain reactions (nested PCR) using hantavirus genotype specific primers. The nested PCR products were sequenced and compared with those from previously epidemic isolates in Shandong and with other representative HV sequences from GenBank. Phylogenetic tree analyses were performed based on the sequences of the M genes.

RESULTSThirty-four HV isolates in Shandong showed 67.1%-100% nucleotide identities. The nucleotide homologies among 6 Hantaan viruses (HTNV) isolates in Shandong were 78.1%-98.7%, while the homologies among 28 Seoul virus (SEOV) isolates in Shandong were 93.7%-100%. There were at least 3 subtypes HTNV (H2, H5, H9) and 2 subtypes SEOV (S2, S3) in Shandong Province.

CONCLUSIONSIn Shandong Province, the homologies of HTNV were lower and there were no predominant subtypes, while the homologies of SEOV were higher and S3 was the predominant subtype. The homologies of SEOV from rodents were higher than those from patients. The distribution of subtypes in Shandong was similar to that of the adjoining provinces. Phylogenetic analyses of the sequences showed geographic clustering of HV in Shandong.

Animals ; Antigens, Viral ; analysis ; Base Sequence ; Genetic Variation ; Hantavirus ; classification ; genetics ; Humans ; Lung ; virology ; Phylogeny ; RNA, Viral ; analysis ; Rodentia ; virology

Highly pathogenic avian influenza viruses (HPAIV) of the H5N1 subtype have spread since 2003 in poultry and wild birds in Asia, Europe and Africa. In Korea, the highly pathogenic H5N1 avian influenza outbreaks took place in 2003/2004, 2006/2007 and 2008. As the 2006/2007 isolates differ phylogenetically from the 2003/2004 isolates, we assessed the clinical responses of chickens, ducks and quails to intranasal inoculation of the 2006/2007 index case virus, A/chicken/Korea/IS/06. All the chickens and quails died on 3 days and 3-6 days post-inoculation (DPI), respectively, whilst the ducks only showed signs of mild depression. The uninoculated chickens and quails placed soon after with the inoculated flock died on 5.3 and 7.5 DPI, respectively. Both oropharyngeal and cloacal swabs were taken for all three species during various time intervals after inoculation. It was found that oropharyngeal swabs showed higher viral titers than in cloacal swabs applicable to all three avian species. The chickens and quails shed the virus until they died (up to 3 to 6 days after inoculation, respectively) whilst the ducks shed the virus on 2-4 DPI. The postmortem tissues collected from the chickens and quails on day 3 and days 4-5 and from clinically normal ducks that were euthanized on day 4 contained the virus. However, the ducks had significantly lower viral titers than the chickens or quails. Thus, the three avian species varied significantly in their clinical signs, mortality, tissue virus titers, and duration of virus shedding. Our observations suggest that duck and quail farms should be monitored particularly closely for the presence of HPAIV so that further virus transmission to other avian or mammalian hosts can be prevented.
Animals ; Antibodies, Viral/blood ; Brain/virology ; *Chickens ; *Coturnix ; *Ducks ; Heart/virology ; Influenza A Virus, H5N1 Subtype/*pathogenicity ; Influenza in Birds/epidemiology/transmission/*virology ; Kidney/virology ; Korea/epidemiology ; Lung/virology ; Virus Shedding

C57BL/6 mice were inoculated intranasally (50 microl) with serial 10-fold dilution of HAB/01 H5N1 virus. Three and five days later, three mice of each group were euthanized. Lung injury was assessed by observation of lung histopathology, virus titers and MCD50 were also measured. Our data showed that H5N1 viral infection in mice resulted in mainly epithelial injury and interstitial pneumonia, featuring significant weight loss, dramatically increased lung wet weight:body weight ratio, inflammatory cellular infiltration, alveolar and interstitial edema, hemorrhage in lungs with high virus titers, and MCD50 was 10(-6.5)/ 0.05 mL. These results suggested that a mouse model of H5N1 viral infection was successfully established which may benefit study of H5N1 avian influenza virus and pathogenic mechanism of host.
Animals ; Brain ; pathology ; virology ; Disease Models, Animal ; Female ; Humans ; Influenza A Virus, H5N1 Subtype ; pathogenicity ; Influenza, Human ; pathology ; virology ; Liver ; pathology ; virology ; Lung ; pathology ; virology ; Mice ; Mice, Inbred C57BL ; Random Allocation ; Spleen ; pathology ; virology