The purpose of this study is to delineate the histopathologic findings of the spleen after Hantaan viral inoculation, which is the largest lymphoid organ in rats, and to identify the viral location by anti-Hantaan virus (HTNV) monoclonal antibody. All the sixty one suckling rats of less than twenty four hours of age were used. Except twenty one rats of control group, twenty-five rats inoculated intracerebrally for the early change and fifteen suckling rats inoculated intramuscularly for the late change were uniformly susceptible to lethal infection with the ROK 84-105-1 strain of seed HTNV. The characteristic histopathologic findings were; appearance of macrophages below the splenic capsule on the 3rd day, small lymphocytes around the periarteriolar sheath on the 5th day increasing in numbers on the 7th day, and a markedly expanded marginal zone with some immunoblasts and plasma cells as well as decreased extramedullary hematopoiesis on the 9th and 14th days. Time of onset of histopathologic changes in spleen thickness, appearance of medium and large lymphocytes and degree of extramedullary hematopoiesis were influenced by inoculation route, whereas expansion of the marginal zone was affected by postnatal age.
Animals ; Animals, Suckling ; Antigens, Viral/analysis ; Hantavirus/immunology ; Hematopoiesis ; Hemorrhagic Fever with Renal Syndrome/*pathology ; Rats ; Rats, Inbred Strains ; Spleen/*pathology

This study was designed to investigate the potential estrogenic effects of perinatal dietary phytoestrogens on the rat uterus. Pregnant rats were divided to three groups provided the following diets: (1) rat chow, (2) rat chow with 7.5% Trifolium (T.) pratense, or (3) rat chow supplemented with 17beta-estradiol (0.5 mg/kg). The dams in each group were kept on the same diet during pregnancy and lactation. Female offspring were euthanized on day 21 at which time body and organ weights were recorded and tissue samples were taken for histology. Immunohistochemistry was performed to detect estrogen receptor alpha (ERalpha) and progesterone receptor (PR) levels. Our results revealed estrogen-like biological effects of perinatal T. pratense exposure. Relative uterus and ovary weights in the experimental groups were increased compared to control. The number of uterine glands and luminal epithelium heights were also increased. However, there were no statistically significant changes detected in the immunostaining intensity of ERalpha and PR between the groups.
Animals ; Animals, Suckling ; Body Weight/drug effects ; Estrogen Receptor alpha/*metabolism ; Female ; Immunohistochemistry ; Isoflavones/*pharmacology ; Lactation ; Maternal Exposure ; Organ Size/drug effects ; Phytoestrogens/*pharmacology ; Plant Components, Aerial/chemistry ; Pregnancy ; Rats ; Rats, Wistar ; Receptors, Progesterone/*metabolism ; Trifolium/*chemistry ; Uterus/*drug effects

Integrin alphavbeta3 plays a major role in various signaling pathways, cell apoptosis, and tumor angiogenesis. To examine the functions and roles of alphavbeta3 integrin, a stable CHO-677 cell line expressing the murine alphavbeta3 heterodimer (designated as "CHO-677-malphavbeta3" cells) was established using a highly efficient lentiviral-mediated gene transfer technique. Integrin subunits alphav and beta3 were detected at the gene and protein levels by polymerase chain reaction (PCR) and indirect immunofluorescent assay (IFA), respectively, in the CHO-677-malphavbeta3 cell line at the 20th passage, implying that these genes were successfully introduced into the CHO-677 cells and expressed stably. A plaque-forming assay, 50% tissue culture infective dose (TCID50), real-time quantitative reverse transcription-PCR, and IFA were used to detect the replication levels of Foot-and-mouth disease virus (FMDV) in the CHO-677-malphavbeta3 cell line. After infection with FMDV/O/ZK/93, the cell line showed a significant increase in viral RNA and protein compared with CHO-677 cells. These findings suggest that we successfully established a stable alphavbeta3-receptor-expressing cell line with increased susceptibility to FMDV. This cell line will be very useful for further investigation of alphavbeta3 integrin, and as a cell model for FMDV research.
Animals ; Animals, Suckling ; CHO Cells ; Cloning, Molecular ; Cricetulus ; DNA, Complementary/genetics/metabolism ; Disease Susceptibility/virology ; Foot-and-Mouth Disease/*genetics/virology ; Foot-and-Mouth Disease Virus/*physiology ; Integrin alphaVbeta3/*genetics/metabolism ; Mice

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is an important pathogen. One of the important virulence traits of EHEC O157:H7 is the capacity to produce attaching and effacing (A/E) lesions on enterocyte. This property encoded by a pathogenicity island termed the locus of enterocyte effacement (LEE). LEE contains ler (LEE-encoded regulator) gene. The product of ler is a central up-regulator of many virulence genes of the LEE. Another important virulence factor of EHEC O157: H7 is Shiga toxin (Stx), encoded by a prophage integrated into the chromosome of O157:H7. In order to obtain an attenuated vaccine candidate, a ler deletion mutant of O157: H7 was constructed by use of suicide vector pCVD442. Meanwhile, due to potential instability of the prophage carrying the stx gene, the prophage was cured with serial passages of bacteria and confirmed by PCR and DNA sequencing. A ler/stx deletion mutant of EHEC O157:H7 was constructed, termed as O157:H7(deltaler/deltastx). The cultural supernatant of O157 ler/stx deletion mutant was inoculated in vero cell culture, and the result indicating that O157 ler/stx deletion mutant lost the toxigenicity to vero cell. Test group and control group of mice were orogstrically inoculated with the O157 ler/stx deletion mutant and the virulent strain O157:H7 EDL933, respectively. Mice were observed daily for clinical signs and weight changes. After inoculation of the deletion mutant, test group of mice (inoculated with O157:H7(deltaler/deltastx)) gained weight normally and experienced no clinical signs. In contrast, control group of mice (inoculated with O157: H7) exhibited weight loss and all died in four days. In another experiment, pregnant mice were orally vaccinated by O157:H7(deltaler/ deltastx) twice at interval of 14 days. Subsequently, the suckling mice were orally challenged with O157:H7 EDL933 at 7 days of age. The results showed that 78.34% of the sucking mice born by vaccinated mice were survival and 12.73% of the sucking mice born by non-vaccinated mice were survival. This study demonstrated that O157 ler/stx deletion mutant lost the toxigenicity to vero cell and to be safety to mice. Oral immunization can induce specific immune responses, and this mutant strain could be used as an attenuated vaccine candidate against EHEC O157.
Administration, Oral ; Animals ; Animals, Suckling ; Antibodies, Bacterial ; blood ; immunology ; Cercopithecus aethiops ; Escherichia coli Infections ; immunology ; mortality ; prevention & control ; Escherichia coli O157 ; genetics ; immunology ; pathogenicity ; Escherichia coli Proteins ; genetics ; Escherichia coli Vaccines ; administration & dosage ; genetics ; immunology ; Female ; Gene Deletion ; Genetic Vectors ; genetics ; Genomic Islands ; genetics ; Immunization ; Lactation ; immunology ; Male ; Mice ; Mutation ; Pregnancy ; Shiga Toxin ; genetics ; Survival Rate ; Trans-Activators ; genetics ; Vaccines, Attenuated ; administration & dosage ; genetics ; immunology ; Vero Cells ; Virulence ; genetics