Purpose: Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers (ARBs) are frequently employed to counteract the detrimental effects of proteinuria on glomerular diseases. However, the effects of ARBs remain poorly examined in pediatric patients with immunoglobulin A (IgA) nephropathy. Herein, we evaluated the efficacy and safety of losartan, an ARB, in pediatric IgA nephropathy with proteinuria. Methods: This prospective, single-arm, multicenter study included children with IgA nephropathy exhibiting proteinuria. Changes in proteinuria, blood pressure, and kidney function were prospectively evaluated before and 4 and 24 weeks after losartan administration. The primary endpoint was the difference in proteinuria between baseline and 24 weeks. Results: In total, 29 patients were enrolled and received losartan treatment. The full analysis set included 28 patients who received losartan at least once and had pre- and post-urinary protein to creatinine ratio measurements (n=28). The per-protocol analysis group included 22 patients who completed all scheduled visits without any serious violations during the study period. In both groups, the mean log (urine protein to creatinine ratio) value decreased significantly at 6 months. After 24 weeks, the urinary protein to creatinine ratio decreased by more than 50% in approximately 40% of the patients. The glomerular filtration rate was not significantly altered during the observation period. Conclusions Losartan decreased proteinuria without decreasing kidney function in patients with IgA nephropathy over 24 weeks. Losartan could be safely employed to reduce proteinuria in this patient population. ClinicalTrials.gov trial registration (NCT0223277)

Human amniotic membrane-derived mesenchymal stem cells (hAM-MSCs) are capable of differentiating into several lineages and possess immunomodulatory properties. In this study, we investigated the soluble factor-mediated immunomodulatory effects of hAM-MSCs. Mitogen-induced peripheral blood mononuclear cell (PBMC) proliferation was suppressed by hAM-MSCs in a dose-dependent manner as well as hAM-MSC culture supernatant. Moreover, interferon-gamma and interleukin (IL)-17 production significantly decreased from PBMC, whereas IL-10 from PBMCs and transforming growth factor beta (TGF-beta) production from hAM-MSCs significantly increased in co-cultures of hAM-MSCs and PBMCs. Production of several MSC factors, including hepatocyte growth factor (HGF), TGF-beta, prostaglandin E2 (PGE2), and indoleamine 2, 3 dioxygenase (IDO), increased significantly in hAM-MSCs co-cultured with PBMCs. These results indicate that the immunomodulatory effects of hAM-MSCs may be associated with soluble factors (TGF-beta, HGF, PGE2, and IDO), suggesting that hAM-MSCs may have potential clinical use in regenerative medicine.
Amnion/cytology/*immunology ; Cell Differentiation/immunology ; Coculture Techniques ; Dinoprostone/genetics/immunology ; Female ; Hepatocyte Growth Factor/genetics/immunology ; Humans ; Immunologic Factors/*immunology ; Immunophenotyping ; Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics/immunology ; Interferon-gamma/immunology ; Interleukin-10/analysis/immunology ; Interleukin-17/analysis/immunology ; Leukocytes, Mononuclear/cytology/immunology ; Mesenchymal Stem Cells/cytology/*immunology ; Pregnancy ; RNA, Messenger/chemistry/genetics ; Regenerative Medicine/methods ; Reverse Transcriptase Polymerase Chain Reaction ; Transforming Growth Factor beta/genetics/immunology

The Staphylococcus (S.) intermedius group (SIG) has been a main research subject in recent years. S. pseudintermedius causes pyoderma and otitis in companion animals as well as foodborne diseases. To prevent SIG-associated infection and disease outbreaks, identification of both staphylococcal exotoxins and staphylococcal cassette chromosome mec (SCCmec) types among SIG isolates may be helpful. In this study, it was found that a single isolate (one out of 178 SIG isolates examined) harbored the canine enterotoxin SEC gene. However, the S. intermedius exfoliative toxin gene was found in 166 SIG isolates although the S. aureus-derived exfoliative toxin genes, such as eta, etb and etd, were not detected. SCCmec typing resulted in classifying one isolate as SCCmec type IV, 41 isolates as type V (including three S. intermedius isolates), and 10 isolates as non-classifiable. Genetic relatedness of all S. pseudintermedius isolates recovered from veterinary staff, companion animals, and hospital environments was determined by pulsed-field gel electrophoresis. Strains having the same band patterns were detected in S. pseudintermedius isolates collected at 13 and 18 months, suggesting possible colonization and/or expansion of a specific S. pseudintermedius strain in a veterinary hospital.
Animals ; Bacterial Toxins/genetics/metabolism ; Cat Diseases/epidemiology/*microbiology ; Cats ; Chromosomes, Bacterial/genetics/metabolism ; Dog Diseases/epidemiology/*microbiology ; Dogs ; Electrophoresis, Gel, Pulsed-Field/veterinary ; Enterotoxins/genetics/metabolism ; Exfoliatins/genetics/metabolism ; Exotoxins/*genetics/metabolism ; Hospitals, Animal ; Humans ; Medical Staff, Hospital ; Molecular Sequence Data ; Pets/microbiology ; Polymerase Chain Reaction/veterinary ; Republic of Korea/epidemiology ; Staphylococcal Infections/epidemiology/microbiology/*veterinary ; Staphylococcus/genetics/isolation & purification ; Staphylococcus intermedius/*genetics/*isolation & purification

BACKGROUND/AIMS: The incidence of Hepatitis B has significantly declined since the introduction of an HBV vaccination program. The aim of this study was to investigate recent clinical features of acute viral hepatitis B (AVH-B) in Korea. METHODS: A total of 2241 patients with acute viral hepatitis were enrolled and their data were collected from nine medical-centers between January 2006 and December 2009. RESULTS: One hundred nineteen (5.3%) of the 2241 were diagnosed as AVH-B. Among 78 patients with AVH-B whose data were analyzed, 50 were male, and the mean age was 38.6 years. In an initial test, mean AST, ALT and total-bilirubin levels were 1296.2 IU/L, 2109.6 IU/L and 9.3 mg/dl, respectively. Positivity frequencies for HBeAg and anti-HBe were 55.1% and 67.9%, respectively, and the mean HBV DNA level was 5.2 log10 copies/ml. The mean length of hospitalization was 11.6 days. During follow-up, AST, ALT and total bilirubin levels were normalized or near-normalized in all patients without serious complications. Sixty-three of 66 (95.4%) patients showed HBsAg loss and 37 (56.1%) patients showed HBsAg seroconversion. Only 3 patients (4.5%) showed persistent hepatitis B viremia. There was no case of death or liver transplantation. Nine patients (11.3%) had received anti-viral agents and their clinical outcomes were not significantly different from those of patients treated without antiviral agents. CONCLUSIONS: The prevalence of AVH-B among acute hepatitis patients is relatively low in Korea. AVH-B infection can be cured without complications in almost all patients, regardless of antiviral treatment.
Acute Disease ; Adult ; Alanine Transaminase/blood ; Antiviral Agents/therapeutic use ; Aspartate Aminotransferases/blood ; Bilirubin/blood ; DNA, Viral/analysis ; Female ; Hepatitis B/*diagnosis/drug therapy/epidemiology ; Hepatitis B Antibodies/blood ; Hepatitis B e Antigens/blood/immunology ; Humans ; Male ; Middle Aged ; Retrospective Studies

Infectious upper respiratory disease (IURD) of Thoroughbred racehorses has been a frequent problem (29.6% of incidence) at the Seoul Race Park (Korea). Risk factors for IURD include the season with a high transfer rate (summer and fall), the stabling period (< or = 3 months), and age (2 to 3 years old), suggesting that the movement and new environment may have depressed the immune system of the horses and decreased their ability to respond properly to pathogens. The bacterial strains (n = 98) isolated from IURD horses included Pseudomonas spp., Escherichia coli, Staphylococcus spp., Streptococcus equi subsp. equi and zooepidemicus.
Animals ; Bacteria/*isolation & purification ; Bacterial Infections/epidemiology/immunology/microbiology/*veterinary ; Horse Diseases/epidemiology/immunology/*microbiology ; Horses ; Incidence ; Microbial Sensitivity Tests ; Republic of Korea/epidemiology ; Respiratory Tract Infections/epidemiology/immunology/microbiology/*veterinary ; Risk Factors

Staphylococcus aureus is a major etiological pathogen of bovine mastitis, which triggers significant economic losses in dairy herds worldwide. In this study, S. aureus strains isolated from the milk of cows suffering from mastitis in Korea were investigated by spa typing and staphylococcal enterotoxin (SE) gene profiling. Forty-four S. aureus strains were isolated from 26 farms in five provinces. All isolates grouped into five clusters and two singletons based on 14 spa types. Cluster 1 and 2 isolates comprised 38.6% and 36.4% of total isolates, respectively, which were distributed in more than four provinces. SE and SE-like toxin genes were detected in 34 (77.3%) isolates and the most frequently detected SE gene profile was seg, sei, selm, seln, and selo genes (16 isolates, 36.3%), which was comparable to one of the genomic islands, Type I nuSabeta. This is a first report of spa types and the prevalence of the recently described SE and SE-like toxin genes among S. aureus isolates from bovine raw milk in Korea. Two predominant spa groups were distributed widely and recently described SE and SE-like toxin genes were detected frequently.
Animals ; Cattle ; Cluster Analysis ; DNA, Bacterial/chemistry/genetics ; Enterotoxins/chemistry/*genetics ; Female ; Genotype ; Mastitis, Bovine/epidemiology/genetics/*microbiology ; Microsatellite Repeats ; Milk/*microbiology ; Polymerase Chain Reaction/veterinary ; Prevalence ; Republic of Korea/epidemiology ; Staphylococcal Infections/epidemiology/microbiology/*veterinary ; Staphylococcus aureus/classification/genetics/*isolation & purification

Paratuberculosis (PTB) is a major disease problem worldwide, and causes major economic losses in the dairy industry. Although PTB has been reported in Korea, no studies have been conducted to determine its prevalence and no program has been developed to control the disease. In this study, the sera of beef (n = 1,056) and dairy cattle (n = 1,105) from all provinces in Korea were tested to determine the prevalence of PTB using two different ELISA: an 'in house' modified absorbed ELISA (P-ELISA) based on sonicated antigen from Mycobacterium avium subsp. paratuberculosis ATCC 19698, and a commercial ELISA (C-ELISA). Receiver operating characteristic analysis was used to determine the cutoff point for P-ELISA. Based on C-ELISA results, the area under the curve for P-ELISA was 0.913 (95% CI, 0.883 to 0.943). Using a cutoff point of 0.100, P-ELISA showed a sensitivity of 62.0% and a specificity of 93.7%. The kappa value and the percent agreement between the two ELISAs were 0.322 and 92.5%, respectively. Both ELISAs showed a significant correlation between age and seropositivity (p < 0.01). According to C-ELISA, 71 of 2,161 sera (3.3%, 95 CI, 2.6% to 4.1%) were test-positive. The national true prevalence of PTB was estimated to be 7.1%. The findings suggest that a control program should be implemented to limit the spread of this disease, and that P-ELISA could be used as a screening test that produces results similar to C-ELISA.
Animals ; Antibodies, Bacterial/blood ; Cattle ; Cattle Diseases/*epidemiology/*microbiology ; Enzyme-Linked Immunosorbent Assay/veterinary ; Female ; Korea/epidemiology ; Male ; Mycobacterium avium subsp. paratuberculosis/*isolation & purification ; Paratuberculosis/blood/*epidemiology ; ROC Curve ; Sensitivity and Specificity ; Seroepidemiologic Studies

Our recent study has provided that the in vitro SEC-induced proliferation of bovine T cells is preceded by a period of a non-proliferative immunoregulation of T cells that may be associated with cytokine production regulated by type 1 or type 2 T cells. Inversion of CD4+:CD8+ T cell ratio and induction of CD8+T cells with immunoregulatory activity could increase the probability of intracellular survival of Staphylococcus aureus (S. aureus). The increase of activated CD8+(ACT2+ BoCD8+) T cells in cows with mastitis caused by S. aureus may be associated with immune-regulatory function in the bovine mammary gland. The difference and similarity between bovine activated CD8+ T cells (CD8+ CD26+)and well-established human CD4+ CD25+ T regulatory (Tr)cells may help to reveal their unique immune regulatory system in the host infected with S. aureus.
Animals ; Cattle ; Cell Proliferation ; Female ; Lymphocyte Activation/immunology ; Mastitis, Bovine/*immunology/microbiology ; Staphylococcal Infections/immunology/*veterinary ; Staphylococcus/*immunology ; *Superantigens ; T-Lymphocytes/*immunology

Escherichia coli O157:H7 is recognized as a significant food-borne pathogen, so rapid identification is important for food hygiene management and prompt epidemiological investigations. The limited prevalence data on Shiga toxin-producing E. coli (STEC) and E. coli O157:H7 in foods and animals in Korea made an assessment of the risks difficult, and the options for management and control unclear. The prevalence of the organisms was examined by newly developed kit-E. coli O157:H7 Rapid kit. For the isolation of E. coli O157:H7, conventional culture, immunomagnetic separation, and E. coli O157:H7 Rapid kit were applied, and multiplex PCR and randomly amplified polymorphic DNA (RAPD) were performed for the molecular determination. There was high molecular relatedness among 11 Korean isolates and 17 U.S. strains at 63% level. Additionally, distinct differentiation between pig and cattle isolates was determined. It implied that RAPD had a capacity to distinguish strains with different sources, however it could not discriminate among isolates according to their differences in the degree of virulence. In antimicrobial susceptibility tests, 45.5% of isolates showed antibiotic resistance to two or more antibiotics. Unlike the isolates from other countries, domestic isolates of E. coli O157:H7 was mainly resistant to ampicillin and tetracylines. In summary, the application of E. coli O157:H7 Rapid kit may be useful to detect E. coli O157:H7 due to its sensitivity and convenience. Moreover, combinational analysis of multiplex PCR together with RAPD can aid to survey the characteristics of isolates.
Abattoirs ; Adhesins, Bacterial/genetics ; Animals ; Cattle ; Cercopithecus aethiops ; Chickens ; Escherichia coli O157/genetics/*isolation&purification ; Escherichia coli Proteins/genetics ; Feces/microbiology ; Food Microbiology ; Hemolysin Proteins/genetics ; Korea ; Meat/*microbiology ; Phylogeny ; Polymerase Chain Reaction/*methods ; Random Amplified Polymorphic DNA Technique/*methods ; *Reagent Kits, Diagnostic ; Shiga-Like Toxin I/genetics ; Shiga-Like Toxin II/genetics ; Swine ; United States ; Vero Cells

Though the aetiology of transmissible spongiform encephalopathies (TSEs) remains uncertain, proteinase resistant prion protein (PrP-Sc), a converted form of the normal cellular prion protein (PrP-C), accumulates in the lysosome of cells of the nervous systems of animals with TSEs. In this study, clinical and epidemiological examinations of bovine spongiform encephalopathy (BSE) were conducted in Korea. During the investigated period, none of the cattle exhibited typical clinical signs of BSE, such as behavioral disturbances, high sensitivity, and abnormal locomotion. Immunohistochemical analysis and western immunoblotting were established to detect PrP-Sc in the brain tissue using monoclonal antibody (MAb) F89/160.1.5, produced by immunizing mice with a synthetic peptide which corresponds to bovine PrP residues 146-159, NH2-SRPLIHFGSDYEDRC-COOH. Although some BSE-like spongiform changes were observed in bovine brains randomly collected from Korean slaughterhouses from 1996 to 1999, no PrP-Sc was detected in those brains with the established immunohistochemistry and western immunoblotting assay. Also, no positive reaction was observed in bovine brains infected with rabies. These immunohistochemical and western immunoblotting methods using MAbs, specifically reactive with conserved epitopes on ruminant PrP, can be used for postmortem diagnosis of BSE. Further, the method can be applied to antemortem and the preclinical diagnosis of ovine scrapie by detecting PrP-Sc in lymphoid tissues, such as the tonsils, third eyelid or peripheral lymph nodes.
Abattoirs ; Animals ; Blotting, Western ; Brain/*pathology ; Brain Stem/pathology ; Cattle ; Encephalopathy, Bovine Spongiform/*epidemiology/pathology ; Immunohistochemistry ; Korea/epidemiology ; PrPSc Proteins/*analysis ; Sheep ; Sheep Diseases/*epidemiology/pathology