• Korean Journal of Veterinary Research
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• v.53 no.4
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• pp.245-251
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• 2013

Porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) have been suspected to have immunosuppressive effects on pigs. To investigate the correlation between these virus infection and the lesions of lymph nodes including sub-mandibular and inguinal lymph node, 44 pigs (PCV2 single, n = 14; PRRSV single, n = 10; PCV2/PRRSV, n = 14; negative control, n = 6) were examined by histopathology and immunohistochemistry. Histopathologically, granulomatous lymphadenitis characterized by lymphoid depletion with histiocytic cells infiltration was observed in PCV-2 single and PCV-2/PRRSV group. Immunohistochemically, there were significant reduction of B and T lymphocytes in lymph nodes of these groups, while the number of macrophages was increased. In only PRRSV infected group, germinal center hypertrophy and lymphoid necrosis were observed. Immunohistochemically, the number of CD3+ T lymphocytes was slightly increased. Severe lymphocytic depletion in PCV-2 infection-related lymph nodes might be associated with producing immunocompromised state in pig. Comparing with PCV-2 infected group, PRRSV produced minor effects on the changes in immune cell population in the lymph nodes of pigs. PRRSV may increase susceptibility of the disease in pigs by disruption of the first defense lines in target organs, such as the alveolar macrophages in lungs.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.1
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• pp.75-79
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• 2008

Blunt trauma, drugs, infection, congenital anomalies of the pancreaticobiliary system, and multisystem diseases are the main causes of acute pancreatitis in children. Various viruses can cause acute pancreatitis, but varicella-induced pancreatitis is unusual and generally observed in adults or immunocompromised patients. We report a rare case of acute pancreatitis associated with varicella-zoster virus infection in a 6-year-old immunocompetent girl. The patient initially presented complaining of severe abdominal pain and repetitive vomiting. The patient had multiple cutaneous crusts that has been caused by preceding varicella infection and had elevated values of serum amylase and lipase. Abdominal ultrasonography demonstrated swelling of the pancreas and pancreatic duct dilatation, findings which were compatible with acute pancreatitis. The patient's clinical and laboratory abnormalities were completely normalized through conservative treatment consisting of fasting, total parenteral nutrition, and analgesic therapy.

• Childhood Kidney Diseases
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• v.9 no.2
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• pp.275-281
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• 2005

Parvovirus B19(PV B19) is a nonenveloped single-stranded DNA virus that causes a wide variety of diseases ranging from benign childhood infection such as slapped-cheek rash(fifth disease) to life threatening diseases such as hydrous fetalis in fetuses or aplastic anemic crises in patients with hemolytic anemia. In immunocompromised hosts including organ transplant recipients, this infection can cause chronic anemia. Recently, the reports of cases of PV B19 infection have been increasing in transplant recipients and most reported cases of PV B19 infection-associated anemia in renal transplant recipients were successfully treated with intravenous immunoglobulin infusion. We experienced two cases of aplastic anemia caused by PV B19 infection in pediatric renal transplant recipients. The patients were an 8 year-old boy and 12-year-old boy who received allograft kidneys from their mothers. Anemia developed 2 weeks after transplantation and their serum was positive for PV B19 PCR. They were treated with 400 mg/kg of intravenous immunoglobulin(IVIG) for 5 consecutive days. In one of the case, anemia was corrected promptly after the first 5-day course of IVIG therapy but in the other, anemia persisted but responded to the second course of IVIG therapy. One year later, the patients have normal hematocrit levels and stable renal function These are the first cases of PV B19 infection treated successfully with IVIG in pediatric renal transplant recipients in Korea. (J Korean Soc Pediatr Nephrol 2005;9:275-281)

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1894-1903
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• 2019

The purpose of this study was to determine the probiotic properties of Lactobacillus brevis KCCM 12203P isolated from the Korean traditional food kimchi and to evaluate the antioxidative activity and immune-stimulating potential of its heat-killed cells to improve their bio-functional activities. Lactobacillus rhamnosus GG, which is a representative commercial probiotic, was used as a comparative sample. Regarding probiotic properties, L. brevis KCCM 12203P was resistant to 0.3% pepsin with a pH of 2.5 for 3 h and 0.3% oxgall solution for 24 h, having approximately a 99% survival rate. It also showed strong adhesion activity (6.84%) onto HT-29 cells and did not produce β-glucuronidase but produced high quantities of leucine arylamidase, valine arylamidase, β-galactosidase, and N-acetyl-β-glucosaminidase. For antioxidant activity, it appeared that viable cells had higher radical scavenging activity in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, while in the 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, heat-killed cells had higher antioxidant activity. Additionally, L. brevis KCCM 12203P showed higher lipid oxidation inhibition ability than L. rhamnosus GG; however, there was no significant difference (p < 0.05) between heat-killed cells and control cells. Furthermore, heat-killed L. brevis KCCM 12203P activated RAW 264.7 macrophage cells without cytotoxicity at a concentration lower than 10⁸ CFU/ml and promoted higher gene expression levels of inducible nitric oxide synthase, interleukin-1β, and interleukin-6 than L. rhamnosus GG. These results suggest that novel L. brevis KCCM 12203P could be used as a probiotic or applied to functional food processing and pharmaceutical fields for immunocompromised people.

• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1216-1225
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• 2014

Biofilm-related infections of Candida albicans are a frequent cause of morbidity and mortality in hospitalized patients, especially those with immunocompromised status. Options of the antifungal drugs available for successful treatment of drug-resistant biofilms are very few, and as such, new strategies need to be explored against them. The aim of this study was to evaluate the efficacy of phenylpropanoids of plant origin against planktonic cells, important virulence factors, and biofilm forms of C. albicans. Standard susceptibility testing protocol was used to evaluate the activities of 13 phenylpropanoids against planktonic growth. Their effects on adhesion and yeast-to-hyphae morphogenesis were studied in microplate-based methodologies. An in vitro biofilm model analyzed the phenylpropanoid-mediated prevention of biofilm development and mature biofilms using XTT-metabolic assay, crystal violet assay, and light microscopy. Six molecules exhibited fungistatic activity at ${\leq}0.5mg/ml$, of which four were fungicidal at low concentrations. Seven phenylpropanoids inhibited yeast-to-hyphae transition at low concentrations (0.031-0.5 mg/ml), whereas adhesion to the solid substrate was prevented in the range of 0.5-2 mg/ml. Treatment with ${\leq}0.5mg/ml$ concentrations of at least six small molecules resulted in significant (p < 0.05) inhibition of biofilm formation by C. albicans. Mature biofilms that are highly resistant to antifungal drugs were susceptible to low concentrations of 4 of the 13 molecules. This study revealed phenylpropanoids of plant origin as promising candidates to devise preventive strategies against drug-resistant biofilms of C. albicans.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1154-1158
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• 2013

Ganciclovir resistance of human cytomegalovirus is associated with mutations in the viral UL97 gene and poses severe problems for immunocompromised patients. In this study, PCR-based restriction fragment length polymorphism and sequencing analyses detected the UL97 D605E mutation in all five clinical isolates from patients with ganciclovir-resistant human cytomegalovirus infection during prolonged ganciclovir therapy, whereas the M460V mutation was only present in 1 of 5 isolates. On the other hand, the detection rates of the D605E mutation in the stored available DNA samples from the donor and allogeneic stem cell transplantation recipients were 66.7% and 93.7%, respectively, suggesting that the presence of D605E mutation was not associated with the ganciclovir exposure. Although the D605E mutation may not be related to ganciclovir resistance, we suggest that this mutation could be an important molecular marker of human cytomegalovirus evolution in East Asian countries. Moreover, the restriction fragment length polymorphism method using the restriction enzyme HaeIII, which is generally used to detect the UL97 A591V mutation, could also detect the D605E mutation and may therefore be a useful tool for future research on the investigation of UL97 gene mutations.

• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1142-1148
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• 2020

Mitochondria play a vital role in iron uptake and metabolism in pathogenic fungi, and also influence virulence and drug tolerance. However, the regulation of iron transport within the mitochondria of Cryptococcus neoformans, a causative agent of fungal meningoencephalitis in immunocompromised individuals, remains largely uncharacterized. In this study, we identified and functionally characterized Mrs3/4, a homolog of the Saccharomyces cerevisiae mitochondrial iron transporter, in C. neoformans var. grubii. A strain expressing an Mrs3/4-GFP fusion protein was generated, and the mitochondrial localization of the fusion protein was confirmed. Moreover, a mutant lacking the MRS3/4 gene was constructed; this mutant displayed significantly reduced mitochondrial iron and cellular heme accumulation. In addition, impaired mitochondrial iron-sulfur cluster metabolism and altered expression of genes required for iron uptake at the plasma membrane were observed in the mrs3/4 mutant, suggesting that Mrs3/4 is involved in iron import and metabolism in the mitochondria of C. neoformans. Using a murine model of cryptococcosis, we demonstrated that an mrs3/4 mutant is defective in survival and virulence. Taken together, our study suggests that Mrs3/4 is responsible for iron import in mitochondria and reveals a link between mitochondrial iron metabolism and the virulence of C. neoformans.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.93-100
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• 2017

Human norovirus (hNoV) infection accounts for the vast majority of virus-mediated gastroenteritis cases worldwide. It causes self-limiting acute illnesses in healthy individuals lasting for a few days, however, in immunocompromised patients, hNoV can establish chronic and potentially fatal infections. Since its discovery in 1968, much effort had been made to develop cell culture and animal infection models to no avail. Only recently, some promising breakthroughs in the development of in vitro infection models have been made. Here, we will contrast and compare those models and discuss what further needs to be done to develop a reliable and robust cell culture model.

• Journal of agricultural medicine and community health
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• v.15 no.1
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• pp.49-55
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• 1990

Zoonoses are those diseases and infections that are naturally transmitted between vertebrate animals and man. At present, approximately 175 diseases caused by virus, rickettsia, bacteria, protozoa and helminthes as well as some of arthropods and the number is continually increasing. Although zoonoses are generally recognized as significant health problems, the actual prevalence and incidence of zoonotic infections is difficult to determine. Medical services in a rural area are scarce and ill persons may have little chance to see a physician. Furthermore, a lack of physician awareness and of appropriate diagnostic support is made often misdiagnosis. In rural Korea, parasitic disease is still important subject in the field of zoonotic infections considering its number and morbidity. Recently there was conspicuous reduction of soil-transmitted parasitic diseases (i.e. ascariasis. hookworms, trichuriasis), but clonorchiasis. intestinal trematodiases and taeniasis are a considerable problem. This is often significantly related to human behavioral patterns based on socio-economic and cultural conditions and linked with the local biologic and physical environment. The most of all parasitic zoonoses to man and animals are the food-transmitted parasitic diseases, and domestic animals such as dog, cat, pig, as well as fat and some mammals, ruminants and birds are act as reservoir hosts. In the present topics, current problems of parasitic zoonoses caused by protozoan infections (i. e. toxoplasmosis, pneumocystosis and cryptosporidiosis) which are the most common opportunistic in AIDS or immunocompromised persons, trematode infections (i.e. clonorchiasis, paragonimiasis and some intestinal tremadodiases). cestode infections such as cysticercosis and sparganosis, and some nematode infections of anisakiasis, thelaziasis and strongyloidiasis, are discussed here those on the occurrence in man and animals and the source of transmission as well as prevention and control measures in Korea.

• Tuberculosis and Respiratory Diseases
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• v.42 no.1
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• pp.93-98
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• 1995

Cryptococcosis is a systemic infection caused by the yeast-like fungus Cryptococcus neoformans. Respiratory tract is the usual portal of infection but relatively few cases of pulmonary cryptococcosis have been reported. Recently the incidence of the disease are increasing because the perception to seek the disease is increasing and immunocompromised hosts are more widespread with introduction of immune-suppressants, steroids and advent of AIDS. Because of nonspecific pattern of clinical manifestation, radiologic findings, differentiating the other diseases is essential and it needs fungal culture and biopsy. We describe a patient in the state of bilateral adrenalectomy due to bilateral ACTH-independent macronodular hyperplasia who developed pulmonary cryptococcosis and was later infected with pulmonary tuberculosis.