• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.353-359
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• 2008

Hepatitis C virus (HCV) is known as the causative agent of blood transmitted hepatitis. Two viral proteins, E2 and NS5A, are known to exert interferon resistance of HCV via PKR pathway. Here, we report a third protein, the RNA-dependent RNA polymerase (NS5B) of HCV, induced interferon resistance inhibiting p56 pathway. p56 was shown to interact with p48 subunit of eukaryotic initiation factor 3 (eIF3). This interaction inhibited formation of ternary complex in translation initiation. Using dual reporter assay system, we observed that the translation decreased when interferon alpha was added to the culture. But, in the presence of HCV NS5B, the translation partly recovered. NS5B and p48 subunit of eIF3 were shown to interact. This interaction seems to inhibit the interaction between p48 and p56. This is the first report that a virus exerts interferon resistance via p56 pathway.

• Archives of Pharmacal Research
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• v.17 no.2
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• pp.93-99
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• 1994

Macrtophages play an important role in defense against virus infection by intrinsic resistance and by extrinsic resistance. Since interferon-induced enzymes which are 2'-5' oligoadenylate synthetase and p1/eIF-2 protein kinase have been shown to be involved in the inhibition of viral replication, I examined the mechanism by which poly I:C, an interferon inducer, exerts its antiviral effects in inflammatory macrophages infected with herpes simplex virus type 1 (HSV-1). The data presented here demonstrate that poly I:C-induced antiviral activity is partially due to the activation of 2'-5' pligoadenylate synthetase. The activation of 2'-5' oligoadenlate A synthetase by poly I:C is also at least mediated via the production of interferon-.betha.. Taken together, these data indicate that interferon-.betha. produced in response to poly I:C acts in an autocrine manner to activate the 2'-5' oligoadenylate synthetase and to induce resistance to HSV-1.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.1037-1040
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• 2015

Hepatitis C is a blood-borne infectious disease of liver, caused by a small enveloped, positive-single stranded RNA virus, called the hepatitis C virus (HCV). HCV belongs to the Flaviviridae family and has 6 genotypes and more than 100 subtypes. It is estimated that 185 million people are infected with HCV worldwide and 5% of these are in Pakistan. The study was designed to evaluate different genotypes of HCV circulating in District Mardan and to know about the behavior of these genotypes to different anti-viral regimes. In this study 3,800 patients were exposed to interferon alfa-2a plus Ribavirin treatment for 6-months and subjected to real-time PCR to check the viral response. Among these 3,677 (97%) patients showed no detectable HCV RNA while 123 (3%) patients (non-responders) remained positive for HCV RNA. Genotypes of their analyzed showed that most of them belonged to the 3a genotype. Non-responders (123) and relapsed (5) patients were subjected to PEG-interferon and Ribavirin therapy for next 6 months, which resulted into elimination of HCV RNA from 110 patients. The genotypes of the persisting resistant samples to anti-viral treatment were 3b, 2a, 1a and 1b. Furthermore, viral RNA from 6 patients remained un-typed while 4 patients showed mixed infections. HCV was found more resistant to antiviral therapy in females as compared to mals. The age group 36-45 in both females and males was found most affected by infection. In general 3a is the most prevalent genotype circulating in district Mardan and the best anti-viral therapy is PEG-interferon plus Ribavirin but it is common practice that due to the high cost patients receive interferon alfa-2a plus Ribavirin with consequent resistance in 3% patients given this treatment regime.

• IMMUNE NETWORK
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• v.1 no.2
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• pp.109-115
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• 2001

Background: The role of the interferon consensus sequence binding protein (ICSBP), a member of interferon regulatory factor family, in protecting against a vesicular stomatitis virus (VSV) infection has not been firmly elucidated. Thus, it was investigated utilizing the human promyelocytic leukemia HL-60 cells which do not express ICSBP. Methods: HL-60 cells were stably transfected with plasmid containing cDNA for either ICSBP or DNA binding domain (DBD) and tested for their VSV-susceptibilities. The susceptibility of each transfectant group to a VSV infection was determined by a plaque assay at 1 h, 24 h, and 48 h post-infection in the presence (500 IU/ml) or absence of interferon ${\alpha}$ ($IFN{\alpha}$). Results: In the absence of $IFN{\alpha}$, the three groups showed similar sensitivities to a VSV infection. However, when pre-treated with IFN, the viral titers in both the ICSBP and control clones steadily decreased over 48 h of incubation, indicating the existence of $IFN{\alpha}$-mediated protection against VSV infection. The $IFN{\alpha}$-treated ICSBP clones appeared to be more resistant to infection compared with the control clones, although the difference was not great. On the contrary, the viral titers in the $IFN{\alpha}$-treated DBD clones increased at 24 h then decreased by 48 h. Conclusion: The expression of truncated ICSBP (DBD) does not appear to underlie the impaired protection against a VSV infection in the DBD clones, since even the control clones lacking ICSBP were protected from a VSV infection. This suggests that ICSBP does not play a critical role in the $IFN{\alpha}$- mediated anti-VSV response of HL-60 cells, although it appears to confer some resistance to a VSV infection.

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.776-780
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• 2004

Interferons are cytokines that confer resistance to viral infection and inhibit cellular proliferation. The interferon alpha gene from human blood samples was amplified, cloned and expressed in E. coli (BL21). Leukocyte chromosomal DNA was used as a source of template DNA. Using specific primers, the gene for HulFN$\{alpha}$-2b was amplified and inserted into the E. coli vector, pET21b, by ligation of the HindIII and BamHI linkers of the vector and insert. The insert was further analyzed by PCR, DNA restriction mapping and sequencing, and expressed in a suitable E. coli strain. The production of this important cellular protein in the laboratory has significant applications in production of the recombinant pharmaceutical proteins.

• The Journal of Internal Korean Medicine
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• v.37 no.4
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• pp.609-623
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• 2016

Objective: This study was undertaken to investigate the effects of Mori folium on insulin resistance and adipose tissue inflammation in an experimental mouse model of obesity.Methods: Obesity was induced in C57BL/6 mice by feeding them a high-fat diet. The mice were divided into four groups (n=6): a normal diet, high-fat diet, high-fat diet with 40 mg of Mori folium, and high-fat diet with 800 mg of Mori folium groups. After 13 wk, the body weights, fasting blood glucose and fasting serum insulin levels, insulin resistance (homeostatic model assessment) levels, oral glucose tolerance test levels, epididymal fat and liver weights, and gene expression of tumor necrosis factor-α, interleukin-6, and interferon-γ were measured. In addition, adipose tissue macrophages were analyzed by fluorescence-activated cell sorting.Results: Mori folium significantly reduced blood glucose levels, oral glucose tolerance levels, and liver weights. It also reduced adipose tissue macrophage numbers and tumor necrosis factor receptor-α gene expression.Conclusions: These results show that Mori folium has insulin resistance reduction and anti-inflammatory effects in an experimental mouse model of obesity.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.228.3-228
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• 2005

• The Journal of Internal Korean Medicine
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• v.39 no.4
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• pp.751-763
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• 2018

Objective: This study was undertaken to investigate how magnolia bark extract affects ob/ob mouse in terms of metabolic inflammation and insulin resistance. Methods: Leptin-deficient ob/ob mice were divided into 2 groups (n=5): a normal saline treatment (=control) and magnolia bark treatment. Wild type mice were the lean group (n=5). After 5 weeks, we measured fasting blood sugar (FBS) and conducted oral glucose tolerance tests (OGTTs) in each group. After 6 weeks, we measured body weight, epididymal fat pad weight, liver weight, serum glucose, serum insulin, and gene expression of tumor necrosis factor-${\alpha}$, interferon-${\gamma}$, and interleukin-6. We characterized the phenotype of adipose tissue macrophages (ATMs) and analyzed fractions of the phenotype in each group by flow cytometry. Results: In the magnolia bark group, fasting blood sugar, oral glucose tolerance levels, and insulin resistance (HOMA-IR) were significantly decreased. The population and proportion of ATMs among leukocytes in adipose tissue were significantly decreased in the magnolia bark group. The population and proportion of M1 type ATMs among ATMs were significantly decreased in the magnolia bark group. Gene expression of tumor necrosis factor-${\alpha}$ was significantly decreased in the magnolia bark group. Conclusions: These results support a positive effect of magnolia bark on metabolic diseases such as insulin resistance and metabolic inflammation in leptin-deficient ob/ob mice.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.89-105
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• 1998

In the past decade, significant progress has been achieved in the battle against hepatitis B virus. In addition to the immunomodulating agents such as interferon-.alpha., and thymosin, many novel antiviral agents have been discovered, among which nucleoside analogues are the mainstay. New-generation compounds such as 3TC and famciclovir have shown promise in the treatment of patients chronically infected by this virus, and are on the line for approval. However, viral rebound after cessation of therapy still remains a major problem. Additionally, the reports on the drug resistance to these antiviral agents suggest that combination therapy will be the eventual strategy (Bartholomew et al., 1997; Tipples et al., 1996). Therefore, developments of safe and effective antiviral agents which do not cross-resist with currently available antiviral drugs are still much needed.

• Korean Journal of Veterinary Research
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• v.52 no.4
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• pp.231-238
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• 2012

The expression profiles of inflammatory cytokines viz. interleukins (IL)-6, IL-8, IL-12, granulocyte macrophage-colony stimulating factor, interferon-${\gamma}$ and tumor necrosis factor-${\alpha}$ in response to subclinical mastitis in indigenous cattle breed Kankrej (n = 6), Gir (Bos indicus) (n = 12) and crossbred (Bos taurus${\times}$Bos indicus) (n = 7) were investigated using quantitative real time PCR. Significant correlation (p < 0.05) was observed between total bacterial load and somatic cell count (SCC) in all three breeds of cattle. All the cytokines were observed to be up-regulated compared to cows with healthy quarters, however, level of their expression varied among three breeds of cattle. In Kankrej most cytokines were found to be transcribed to higher levels than in other two breeds; the milk had higher load of bacteria but not so high SCC, implying that Kankrej has a higher inherent resistance against mastitis. The results of present study indicated that mammary glands of crossbred cattle are more sensitive to bacterial infection than indigenous breed of cattle as they elicit immune response at lower bacterial load and result into higher SCC. Research on identification of factors responsible for differentially expressed cytokines profiles and use of cytokines as immunomodulatory tools can pave way for formulating control strategies against bovine mastitis.