Kyoung-Hee Han

Influence of Bacterial Presence on Biofilm Formation of Candida albicans

Purpose Candida albicans is an opportunistic pathogen that is commonly found in human microflora. Biofilm formation (BF) is known as a major virulence factor of C. albicans. The aim of this study was to examine the influence of bacterial presence on biofilm formation of C. albicans. Materials and Methods The BF of Candida was investigated when it was co-cultured with C. albicans (C. albicans 53, a yeast with a low BF ability, and C. albicans 163, a yeast with high BF ability) and bacteria. BF was assessed with XTT reduction assay. A scanning electron microscope was used to determine the structure of the biofilm, and real-time reverse transcriptase polymerase chain reaction was used to amplify and quantify hyphae-associated genes. Results Co-culturing with two different types of bacteria increased the BF value. Co-culturing with C. albicans 53 and 163 also increased the BF value compared to the value that was obtained when the C. albicans was cultured individually. However, co-culturing with bacteria decreased the BF value of C. albicans, and the BF of C. albicans 163 was markedly inhibited. The expression of adherence and morphology transition related genes were significantly inhibited by co-culturing with live bacteria. Conclusion Bacteria have a negative effect on the formation of biofilm by C. albicans. This mechanism is the result of the suppression of genes associated with the hyphae transition of C. albicans, and bacteria particles physically affected the biofilm architecture and biofilm formation.

Electrophysiological and Behavioral Changes by Phosphodiesterase 4 Inhibitor in a Rat Model of Alcoholic Neuropathy

Objective Alcoholic neuropathy is characterized by allodynia (a discomfort evoked by normally innocuous stimuli), hyperalgesia (an exaggerated pain in response to painful stimuli) and spontaneous burning pain. The aim of the present study is to investigate the effect of rolipram, a phosphodiesterase 4 inhibitor, against alcohol-induced neuropathy in rats. Methods Allodynia was induced by administering 35% v/v ethanol (10 g/kg; oral gavage) to Spraue-Dawley rats for 8 weeks. Rolipram and saline (vehicle) were administered intraperitoneally. Mechanical allodynia was measured by using von Frey filaments. Somatosensory evoked potential (SEP) was proposed as complementary measure to assess the integrity of nerve pathway. Results The ethanol-induced mechanical allodynia began to manifest from 3 week, and then peaked within 1 week. Beginning from 3 week, latency significantly started to increased in control group. In rolipram treated rats, the shorter latency was sustained until 8 weeks (p<0.05). The mechanical allodynia, which began to manifest on the 3 weeks, intraperitoneal injections of rolipram sustained statistical difference until 8 weeks, the final week of the study (p<0.05). Conclusion This study suggests that rolipram might alleviate mechanical allodynia induced by alcohol in rats, which clearly has clinical implication.

A case of pseudomyxoma peritonei associated with borderline mucinous tumor of ovary with invasive metastasis of bladder

Pseudomyxoma peritonei (PMP) is an uncommon entity characterized by large amount of mucinous-jelatinous fluid disseminated in abdominal cavity and pelvic cavity with implants on omentum and bowel. The symptoms of this disease are mostly abdominal distension, dyspepsia, and intraabdominal palpable mass. The origin of PMP is under investigation yet, that is known to arise from appendix, ovary mostly. Also it’s etiology, treatment, and prognosis are speculative. Rare cases were reported that have invasion to other organ except appendix and ovaries, but we experienced a case of PMP associated with borderline mucinous tumor of ovary with invasive metastasis of bladder. So we report this case with a brief review with literature.