To investigate the possibility of transmission of CTX-M-producing Escherichia coli isolates among humans and animals, we compared CTX-M-producing E. coli isolates showing the same genotype from humans and dogs in Korea. Sixteen CTX-M-producing E. coli isolates from animals were selected and their genotypes were identified using MLST. Among clinical CTX-M-producing E. coli isolates from humans, which have been identified in previous studies, 12 isolates showing the same STs with those of E. coli isolates from animals were selected. For these 28 CTX-M-producing E. coli isolates, identification of bla CTX-M genes and their genetic environments, antimicrobial susceptibility testing, extended MLST, and PFGE were performed. Some CTX-M-producing E. coli isolates from humans showed the same genotypes, such as ST10, ST38, ST58, and ST95, but different CTX-M enzymes and PFGE patterns. Thus, it can be concluded that dissemination of ESBL-producing E. coli isolates between humans and animals is rare so far.
Animals* ; Dogs ; Escherichia coli* ; Escherichia* ; Genotype ; Humans* ; Korea*

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are among the most common causes of chronic liver disease worldwide. The host immune pressure against hepatitis viruses during the chronic infection has led to mutations in their coding genes, which could play a pivotal role in the clinical outcomes of chronic patients. Our recent molecular epidemiologic studies regarding the HBV precore/core (preC/C) regions and HCV nonstructural 5B (NS5B) protein suggest the presence of distinct CD4 T cell immune pressure against HBV and HCV in Korean chronic patients. However, induced HBV and HCV mutations seem to exert an opposite effect on Korean chronic hepatitis B (CHB) and chronic hepatitis C (CHC) patients, respectively. On the basis of two of our recent papers, we focused in this review on the relationships between the mutation patterns of HBV preC/C and HCV NS5B, which were presumed to be caused by distinct CD4 T cell pressure in the Korean population and their effect on the clinical outcomes and liver disease progression of CHB and CHC patients.
Clinical Coding ; Epidemiologic Studies ; Hepacivirus* ; Hepatitis B virus* ; Hepatitis B* ; Hepatitis B, Chronic ; Hepatitis C* ; Hepatitis C, Chronic ; Hepatitis Viruses ; Hepatitis* ; Humans ; Liver Diseases

Human immunodeficiency virus type 1 (HIV-1)-infected cells respond to the infection with different outcomes depending on their cell type. The interplay of cellular and viral proteins is a key player of differences in virus replication and disease progression. Myeloid cells, including monocytes, macrophages, and myeloid dendritic cells (mDCs) play a crucial role in the transmission and pathogenesis of HIV. The viral protein Tat, which is the viral transcriptional activator, modulates the expression of both HIV and cellular genes in these myeloid cells. This review will focus on recent advances on the interplay between HIV and myeloid cells and will discuss how this interaction may contribute to HIV pathogenesis. A better understanding of the pathogenesis of HIV disease will provide us with the scientific rationale for novel approaches to prevention.
Dendritic Cells ; Disease Progression ; HIV* ; HIV-1* ; Humans* ; Macrophages ; Monocytes ; Myeloid Cells* ; Viral Proteins ; Virus Replication

Lyme disease is the most common vector-borne disease in the United States and Europe, caused by a tick-borne spirochete, Borrelia burgdorferi. Life cycle alternation between arthropod and mammals enhanced B. burgdorferi to adapt to two diverse niches. Although B. burgdorferi infection in these reservoir hosts appears asymptomatic, infection in human can typically cause inflammation in the skin, nervous system, musculoskeletal system and heart. In this review, we discuss the basic molecular characteristics and cell biology of B. burgdorferi and provide an overview of spirochete-induced activation of innate and adaptive immunity, resulting in particular immunopathology. Advancing understanding of the immune evasion mechanisms of B. burgdorferi provides important implications for ongoing research and clinical practice of Lyme disease.
Adaptive Immunity ; Arthropods ; Borrelia burgdorferi ; Europe ; Heart ; Humans ; Immune Evasion ; Inflammation ; Life Cycle Stages ; Lyme Disease* ; Mammals ; Musculoskeletal System ; Nervous System ; Skin ; Spirochaetales ; United States

Whether we are aware or not, diverse microorganisms are living on almost all environmentally exposed surfaces on our body without eliciting harmful immune responses. In fact, recent understanding from numerous studies indicates that our health is highly dependent on the contribution of intestinal commensal bacteria. It appears through its symbiotic interaction with the host, which is the result of millions of years of co-evolution, the microbiota shapes the immune system. In this review, we discuss the relationship between host physiology and commensal bacteria and explore the molecular mechanisms by which the adaptive immune system is influenced by the intestinal microbiota.
Bacteria ; Dysbiosis ; Immune System* ; Microbiota* ; Physiology

Monocytes and macrophages regulate host immune system against infectious pathogens. Activated macrophages play an important role in restricting the multiplication and dissemination of pathogens. The concept of alternative activation of macrophages might provide useful insights into pathology of infectious diseases. M1 macrophages (classically activated macrophages) and M2 macrophages (alternatively activated macrophages) are associated with responses to tissue remodeling, pro-inflammatory and anti-inflammatory reactions in various infectious diseases. However, the relevance of macrophage polarization in several infectious diseases was not revealed clearly. Macrophage plasticity and polarization should be considered as a useful conceptual framework for understanding the unknown pathogenesis of infectious diseases. Here we reviewed the recent progress on macrophage polarization and its characters in infectious diseases.
Communicable Diseases ; Immune System ; Macrophages* ; Monocytes ; Pathology ; Plastics

Human Respiratory Syncytial virus (hRSV) is a leading cause of severe lower respiratory tract diseases in the pediatric population.hRSV frequently causes severe morbidity and mortality in high risk groups including infants with congenital heart disease and the immunosuppressed patients. Although hRSV is recognized as a major public health threat and economic burden worldwide, there is no licensed vaccine and effective therapeutic agent. Viral nonstructural (NS) proteins have been known to play multiple functions for efficient viral replication and pathogenesis. Especially, diverse functions of influenza A virus NS1 have been extensively studies. Recent studies demonstrated that NS1 and NS2 of RSV also exert diverse functions to modulate cellular environment and antiviral immune responses. Since NS proteins of RSV are required for efficient replication and pathogenesis, NS mutant viruses have been tested as live-attenuated vaccines. This review will outline the recent progress in understanding the various functions of RSV NS1 and NS2.
Heart Defects, Congenital ; Humans ; Infant ; Influenza A virus ; Interferons ; Mortality ; Public Health ; Respiratory Syncytial Virus, Human ; Respiratory Syncytial Viruses* ; Respiratory Tract Diseases ; Vaccines

For our survey of the infection frequency and mixed infection of the viruses causing acute respiratory syndromes, we analyzed those viruses from acute respiratory patients in Seoul. Total 1,038 specimens of oropharyngeal swab were tested by the real-time polymerase chain reaction (PCR) kit (Kogenebiotech, Korea) from Jan. to Dec. in 2013. Virus detection rate causing acute respiratory infection was 46% (476/1,038). The most frequently isolated virus was only hRV (21.6%, 103/476), followed by only ADV (8.96%, 93/476), only IFV A (H3N2) (18.1%, 86/476), and only hCoV (7.8%, 37/476) etc. Most of acute respiratory viruses had severe fever. Infection frequency information and mixed infection status on respiratory viruses circulating in Seoul will be helpful for the management of acute respiratory infection and for epidemiological continuous studies.
Coinfection* ; Fever ; Humans ; Real-Time Polymerase Chain Reaction ; Seoul

Human adenovirus type 5 (hAd5) vectors have been demonstrated to be useful vehicles for gene expressions in animals. However, it has not been reported whether hAd5 transduction might be hampered in the sera of livestock animals in Republic of Korea. We collected 205 samples of livestock animals, such as pig (n=84), cattle (n=84), and goat (n=37) in Korea. The neutralizing antibody (NAb) titers to hAd5 virus were less than 15 in most of samples. Only 8% of goat samples had a NAb titer of 15 or 30. Thus, we showed that hAd5 virus was not neutralized in sera from cattle, pig, and goat, and suggest that the hAd5 vector could be used for the effective delivery of vaccines or proteins in livestock animals in the field.
Adenoviruses, Human* ; Animals ; Antibodies, Neutralizing ; Cattle* ; Gene Expression ; Goats* ; Korea ; Livestock ; Republic of Korea* ; Vaccines

It has been previously demonstrated that dystrophin is cleaved in the cardiac myocyte by the viral protease 2A following infection with Coxsackievirus B3 (CVB3). The viral protease 2A mediated cardiomyopathy can be prevented by inhibiting cleavage of dystrophin. However, it is less clear whether uncleaved dysdrophin have other heart protective effect in coxsackievirus infection. To address this, we generated a Balb/C background mouse that had a point mutation in dystrophin that prevents cleavage by protease 2A (KI). We show here that when mice expressing cleavage-resistant dystrophin were infected with CVB3, there was increased cardiac myocyte apoptosis. Bax and Bcl-X(L) mRNA ratio was significantly increased in KI mice heart compare to wild type mice heart. We found cleavage-resistant dystrophin induced the apoptosis related enzyme capspase-3 and caspase-8 activity. In addition, TUNEL stain was observed many TUNEL positive cardiac myocyte in KI mice heart compare to wild type mice heart (3.7% vs 0.3%). However, zVAD treatment for apoptosis blocking was significantly decreased myocardium damage and fibrosis in KI mice heart. These findings indicated that uncleaved dystrophin may have a critical role in cardiac myocyte viral propagation. Uncleaved dystrophin mutant induced cardiac myocyte apoptosis. It delayed coxsackievirus propagation in cardiac myocyte and could prevent cardiac myocyte death.
Animals ; Apoptosis* ; Cardiomyopathies ; Caspase 8 ; Coxsackievirus Infections ; Dystrophin* ; Fibrosis ; Heart* ; In Situ Nick-End Labeling ; Mice* ; Myocardium ; Myocytes, Cardiac* ; Point Mutation ; RNA, Messenger