• Journal of Microbiology
• /
• 제45권1호
• /
• pp.29-33
• /
• 2007

Salmonella typhimurium, causing mouse typhoid, infects hosts such as macrophage cells, and proliferates in intracellular vacuoles causing infected cells to trigger numerous genes to respond against the infection. In this study, we tried to identify such genes in RAW264.7 cells by using the PCR screening method with degenerate primers. Fourteen genes were found to be differentially expressed after a 4 h infection in which the expression of 8 genes increased while expression of the others decreased. Most of the genes were involved in proinflammatory responses such as cytokines production and cell death. The mutation in msbB gene encoding the myristoyl transferase in lipid A of lipopolysaccharide (LPS) resulted in much lower toxicity to the inoculated animals. We compared the expression of the identified genes in wild-type and msbB-mutated S. typhimurium infections and found that Lyzs encoding lysozyme type M was differentially expressed. This gene is quite likely to be related to bacterial survival in the host cells.

• 대한수의학회지
• /
• 제57권1호
• /
• pp.37-42
• /
• 2017

Getah virus (GETV) infection causes sporadic outbreaks of mild febrile illness in horses and reproductive failure in pigs. In this study, we established a reverse transcription polymerase chain reaction (RT-PCR) method to detect GETV from suspected virus-infected samples. The reaction conditions were optimized and validated by using RNA extracted from GETV propagated in cell culture. A GETV-specific GED4 primer set was designed and used to amplify a 177 bp DNA fragment from a highly conserved region of the E1 glycoprotein gene in the GETV genome. RT-PCR performed with this primer set revealed high sensitivity and specificity. In the sensitivity test, the GED4 primer set detected GETV RNA at the level of $10^{2.0}\;TCID_{50}/mL$. In the specificity test, the GED4 primer set amplified only a single band of PCR product on the GETV RNA template, without non-specific amplification, and exhibited no cross-reactivity with other viral RNAs. These results suggest that this newly established RT-PCR method is useful for accurate identification of GETV infection in animals.

• 대한의생명과학회지
• /
• 제24권3호
• /
• pp.275-279
• /
• 2018

Inflammatory bowel disease (IBD) is increasing in prevalence in developed countries but the cause of this increase is unclear. In animal models of IBD and in human IBD patients, alterations in the tight junctional proteins have been observed, suggesting that the intestinal microflora may penetrate the underlying colonic tissue and promote inflammation. Enterotoxigenic Bacteroides fragilis (ETBF) causes inflammatory diarrhea in human and is implicated in inflammatory bowel diseases. However, it is unclear whether alterations in tight junctional proteins occur during ETBF infection in mice. In this brief communication, we report that ETBF infection induces up-regulation of claudin-2 and down-regulation of claudin-5 through B. fragilis toxin (BFT) activity in the large intestine of C57BL/6 mice. In contrast, BFT did not induce changes in tight junctional proteins in the HT29/C1 cell line, suggesting that analysis of biological activity of BFT in vivo is important for evaluating ETBF effects.

• Biomolecules & Therapeutics
• /
• 제6권2호
• /
• pp.191-198
• /
• 1998

Vsrio vulnificus is an estuarine gram-negative human pathogen that affects people with chronic hepatitis, alcoholic cirrhosis, diabetes mellitus or other underlying diseases. V. vulnificus infection is mediated primarily by consumption of raw fish or by exposure of pre-existing wounds to seawater, causing permanent tissue damages or fatal septic shock. We have been developing a vaccine against V. vulnificus composed of whole cell Iysate of a V. vulnificus O-antigen serotype 4 strain. Oral administration of the V. vulnificus;oral vaccine;immunogenicity;protective efficacy vaccine elicited a high serum antibody response in rabbits. The induced antibodies were reactive not only to the homologous strain but also to heterologous O-antigen serotype strains, indicating cross-reactivities among serotypes. Western blot analysis revealed that the antibodies are mainly specific for outer membrane proteins (OMPs) and reacted equally well with OMPs purified from 9 O-antigen serotypes. The rabbit antisera showed opsonophagocytic killing activity against heterologous strains as well as the homologous strain. Passively transferred rabbit antisera into mice were protective against a lethal V. vulnificus infection. These data demonstrate that oral administration of the V. vulnificus vaccine induced a systemic antibody response which had a protective efficacy against V. vulnificus infections, suggesting that this vaccine preparation could be used to develop an oral vaccine against V. vulnificus.

• Journal of Microbiology and Biotechnology
• /
• 제31권11호
• /
• pp.1481-1489
• /
• 2021

Early and accurate detection of pathogens is important to improve clinical outcomes of bloodstream infections (BSI), especially in the case of drug-resistant pathogens. In this study, we aimed to develop a culture-independent digital PCR (dPCR) system for multiplex detection of major sepsis-causing gram-negative pathogens and antimicrobial resistance genes using plasma DNA from BSI patients. Our duplex dPCR system successfully detected nine targets (five bacteria-specific targets and four antimicrobial resistance genes) through five reactions within 3 hours. The minimum detection limit was 50 ag of bacterial DNA, suggesting that 1 CFU/ml of bacteria in the blood can be detected. To validate the clinical applicability, cell-free DNA samples from febrile patients were tested with our system and confirmed high consistency with conventional blood culture. This system can support early identification of some drug-resistant gram-negative pathogens, which can help improving treatment outcomes of BSI.

• Archives of Pharmacal Research
• /
• 제27권4호
• /
• pp.361-370
• /
• 2004

The discovery of insulin receptor substrate (IRS) proteins and their role to link cell surface receptors to the intracellular signaling cascades is a key step to understanding insulin and insulin-like growth factor (IGF) action. Moreover, IRS-proteins coordinate signals from the insulin and IGF receptor tyrosine kinases with those generated by proinflammatory cytokines and nutrients. The IRS2-branch of the insulin/IGF signaling cascade has an important role in both peripheral insulin response and pancreatic $\beta$-cell growth and function. Dysregulation of IRS2 signaling in mice causes the failure of compensatory hyperinsulinemia during peripheral insulin resistance. IRS protein signaling is down regulated by serine phosphorylation or protea-some-mediated degradation, which might be an important mechanism of insulin resistance during acute injury and infection, or chronic stress associated with aging or obesity. Under-standing the regulation and signaling by IRS1 and IRS2 in cell growth, metabolism and survival will reveal new strategies to prevent or cure diabetes and other metabolic diseases.

• Asian-Australasian Journal of Animal Sciences
• /
• 제3권4호
• /
• pp.293-298
• /
• 1990

Pathogen infections or mastitis inflammations usually develop differently on each udder of lactating cow. Although healthy udders will be attacked by the mastitis pathogens or the pathogens from blood in a long term, they would not be always inflamed. Somatic cell counts (SCC) in milk, which is utilized as an index of mastitis diagnosis, and the relation among SCC and milk constituents will have to be examined on each udder individually. Twelve cows of a Holstein cow herd in Nasu Research Station, which were suffering clinical or non-clinical mastitis, were selected, and SCC and milk constituents on each udder milk were measured. The effects of mastitis infection on udder milk components were relatively small except lactose content on udder milks of non-clinical mastitis (SCC< $10.0{\times}10^5$ per ml milk). On udder milks of clinical mastitis, however, high negative correlations were recognized between SCC and milk components. On different sampling days, high contents of fat and protein corresponded to that of total solids.

• Investigative Magnetic Resonance Imaging
• /
• 제24권1호
• /
• pp.61-65
• /
• 2020

Langerhans cell histiocytosis (LCH) is generally considered a childhood disease that exhibits various nonspecific clinical and radiological manifestations that mimic infection or malignancy. Here, we present a case of LCH involving the rib in an adult patient. CT and MRI revealed an expansile lytic lesion with periosteal reaction on the left 8th rib, suggesting a malignant bone tumor. Surgical resection was performed and histopathological examination was consistent with LCH. Owing to its rare occurrence in adults and nonspecific aggressive features, LCH should be included in the differential diagnosis of an aggressive-appearing rib lesion in both adults and children.

• Journal of Plant Biology
• /
• 제39권3호
• /
• pp.215-221
• /
• 1996

Sorghum leaf tissues showing the early acute response of systemic infection with maize dwarf mosaic virus (MDMV) strain A, contained unusual virus-induced cytological modifications including cell wall thickenings and protrusions, intercellular vesicles termed as "paramural bodies", modified plasmodesmata, abnormal plastids, and cylindrical inclusion bodies. Abnormal cell wall, some of which associated with paramural bodies, was frequently contained modified plasmodesmata. Various abnormal plastids were located within infected cells of leaf tissues showing the early acute response. The most important changes in chloroplast seen in the tissues are the presence of small vesicles, deformation of membranes, reduction in granal stack height, disappearance of osmiophilic globules and degeneration of stuctures. The cytological modification was not occurred in nucleus but a group of degenerated mitochondria with abnormal membranes attached to cylindrical inclusion bodies were observed. It was hard more or less to prove the relationship clearly between virus and cellular organelles in virus replication.plication.

• Journal of Microbiology and Biotechnology
• /
• 제16권8호
• /
• pp.1292-1300
• /
• 2006

Aeromonas encheleia, a potential human intestinal pathogen, was shown to infect a human intestinal epithelial cell line (Caco-2) in a noninvasive manner. The transcriptional profile of the Caco-2 cells after infection with the bacteria revealed an upregulated expression of genes involved in chloride secretion, including that of phospholipase A2 (PLA2) and platelet-activating factor (PAF) acetylhydrolase (PAFAH2). This was also confirmed by a real-time RT-PCR analysis. As expected from PLA2 induction, PAF was produced when the Caco-2 cells were infected with the bacteria, and PAF was also produced when the cells were treated with a bacterial culture supernatant including bacterial extracellular proteins, yet lacking lipopolysaccharides. Bacterial aerolysin was shown to induce the production of PAF.