We recently observed the emergence of fluconazole-resistant Candida parapsilosis bloodstream isolates harboring a Y132F substitution in Erg11p in South Korea. These Y132F isolates had a higher propensity to cause clonal transmission than other fluconazole-resistant isolates and persisted within hospitals for several years, as revealed by microsatellite typing.

Introduction With the advent of genetically modified mice, it seems particularly advantageous to develop a mouse model of diabetic erectile dysfunction. Aim To establish a mouse model of type I diabetes by implementation of either multiple low-dose streptozotocin (STZ) protocol or single high-dose STZ protocol and to evaluate morphologic alterations in the cavernous tissue and subsequent derangements in penile hemodynamics in vivo. Methods Eight-week-old C57BL/6J mice were divided into three groups: a control group, a group administered the multiple low-dose STZ protocol (50 mg/kg × 5 days), and a group administered the single high-dose STZ protocol (200 mg/kg). Main Outcome Measures After 8 weeks, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was then harvested and stained with hydroethidine (in situ analysis of superoxide anion), TUNEL, or antibodies to nitrotyrosine (marker of peroxynitrite formation), PECAM-1, smooth muscle α-actin, and phospho-eNOS. Penis specimens from a separate group of animals were used for phospho-eNOS and eNOS western blot or cGMP determination. Results Erectile function was significantly less in diabetic groups than in control group. The generation of superoxide anion and nitrotyrosine and the number of apoptotic cells in both cavernous endothelial and smooth muscle cells were significantly higher in diabetic groups than in control group. Cavernous tissue phospho-eNOS and cGMP expression and the number of endothelial and smooth muscle cells were lower in diabetic groups than in control group. Both diabetic models resulted in similar structural and functional derangements in the corpus cavernosum; however, the mortality rate was higher in mice receiving single high-dose of STZ than in those receiving multiple low-doses. Conclusion The mouse model of type I diabetes is useful and technically feasible for the study of the pathophysiologic mechanisms involved in diabetic erectile dysfunction.

Candida auris is an emerging worldwide fungal pathogen. Over the past 20 years, 61 patient isolates of C. auris (4 blood and 57 ear) have been obtained from 13 hospitals in Korea. Here, we reanalyzed those molecularly identified isolates using two matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) systems, including Biotyper and Vitek MS, followed by antifungal susceptibility testing, sequencing of the ERG11 gene, and genotyping. With a research-use-only (RUO) library, 83.6% and 93.4% of the isolates were correctly identified by Biotyper and Vitek MS, respectively. Using an in vitro diagnostic (IVD) library of Vitek MS, 96.7% of the isolates were correctly identified. Fluconazole-resistant isolates made up 62.3% of the isolates, while echinocandin- or multidrug-resistant isolates were not found. Excellent essential (within two dilutions, 96.7%) and categorical agreements (93.4%) between the Clinical and Laboratory Standards Institute (CLSI) and Vitek 2 (AST-YS07 card) methods were observed for fluconazole. Sequencing ERG11 for all 61 isolates revealed that only 3 fluconazole-resistant isolates showed the Erg11p amino acid substitution K143R. All 61 isolates showed identical multilocus sequence typing (MLST). Pulsed-field gel electrophoresis (PFGE) analyses revealed that both blood and ear isolates had the same or similar patterns. These results show that MALDI-TOF MS and Vitek 2 antifungal susceptibility systems can be reliable diagnostic tools for testing C. auris isolates from Korean hospitals. The Erg11p mutation was seldom found among Korean isolates of C. auris, and multidrug resistance was not found. Both MLST and PFGE analyses suggest that these isolates are genetically similar.

Pericytes are known to play critical roles in vascular development and homeostasis. However, the distribution of cavernous pericytes and their roles in penile erection is unclear. Herein we report that the pericytes are abundantly distributed in microvessels of the subtunical area and dorsal nerve bundle of mice, followed by dorsal vein and cavernous sinusoids. We further confirmed the presence of pericytes in human corpus cavernosum tissue and successfully isolated pericytes from mouse penis. Cavernous pericyte contents from diabetic mice and tube formation of cultured pericytes in high glucose condition were greatly reduced compared with those in normal conditions. Suppression of pericyte function with anti-PDGFR-β blocking antibody deteriorated erectile function and tube formation in vivo and in vitro diabetic condition. In contrast, enhanced pericyte function with HGF protein restored cavernous pericyte content in diabetic mice, and significantly decreased cavernous permeability in diabetic mice and in pericytes-endothelial cell co-culture system, which induced significant recovery of erectile function. Overall, these findings showed the presence and distribution of pericytes in the penis of normal or pathologic condition and documented their role in the regulation of cavernous permeability and penile erection, which ultimately explore novel therapeutics of erectile dysfunction targeting pericyte function.

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eWe investigated the azole resistance mechanisms and clinical features of fluconazole-nonsusceptible (FNS) isolates of Candida tropicalis recovered from Korean surveillance cultures in comparison with fluconazole-less-susceptible (FLS) isolates. Thirtyfive clinical isolates of C. tropicalis, comprising 9 FNS (fluconazole MIC, 4 to 64 g/ml), 12 FLS (MIC, 1 to 2 g/ml), and 14 control (MIC, 0.125 to 0.5 g/ml) isolates, were assessed. CDR1, MDR1, and ERG11 expression was quantified, and the ERG11 and UPC2 genes were sequenced. Clinical features of 16 patients with FNS or FLS bloodstream isolates were analyzed. Both FNS and FLS isolates had >10-fold higher mean expression levels of CDR1, MDR1, and ERG11 genes than control isolates (P values of <0.02 for all). When FNS and FLS isolates were compared, FNS isolates had 3.4-fold higher mean ERG11 expression levels than FLS isolates (P ‫؍‬ 0.004), but there were no differences in those of CDR1 or MDR1. Of all 35 isolates, 4 (2 FNS and 2 FLS) and 28 (8 FNS, 11 FLS, and 9 control) isolates exhibited amino acid substitutions in Erg11p and Upc2p, respectively. Both FNS and FLS bloodstream isolates were associated with azole therapeutic failure (3/4 versus 4/7) or uncleared fungemia (4/6 versus 4/10), but FNS isolates were identified more frequently from patients with previous azole exposure (6/6 versus 3/10; P ‫؍‬ 0.011) and immunosuppression (6/6 versus 3/10; P ‫؍‬ 0.011). These results reveal that the majority of FNS C. tropicalis isolates show overexpression of CDR1, MDR1, and ERG11 genes, and fungemia develops after azole exposure in patients with immunosuppression. Candida tropicalis has become an important cause of bloodstream infections (BSIs) in seriously ill patients (1-3). Although C. tropicalis is usually susceptible to azole antifungals, 7 to 40% of clinical isolates have recently been reported to be resistant to azoles, particularly fluconazole (2-5). The mechanisms responsible for acquired azole resistance are well-characterized in Candida albicans and include mutations in the ERG11 gene, which encodes the drug target enzyme (lanosterol 14␣-demethylase), overexpression of ERG11, and overexpression of genes encoding efflux pumps (6). In C. tropicalis, overexpression of ERG11 associated with missense mutations has been described as the most frequent azole resistance mechanism in clinical isolates (7,8). However, the azole resistance mechanisms of C. tropicalis remain a matter of debate, and only five studies have been reported to date (7-11). In addition, there is a lack of substantial research on mutations in the transcription factor Upc2p of C. tropicalis, which can induce ERG11 overexpression and contribute to the development of fluconazole resistance in C. albicans (12)(13)(14).Fluconazole MIC distributions of wild-type C. tropicalis ranged from 0.125 to 64 g/ml following 24 h of incubation using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution (BMD) methods, and their modal MIC values were 0.125 to 0.5 g/ml (6). Recently, the CLSI es...

Introduction It has been suggested that transforming growth factor-β1 (TGF-β1) plays an important role in the pathogenesis of diabetes-induced erectile dysfunction. Aim To investigate the expression and activity of Smad transcriptional factors, the key molecules for the initiation of TGF-β-mediated fibrosis, in the penis of streptozotocin (STZ)-induced diabetic rats. Methods Fifty-two 8-week-old Sprague–Dawley rats were used and divided into control and diabetic groups. Diabetes was induced by an intravenous injection of STZ. Main Outcome Measures Eight weeks later, erectile function was measured by electrical stimulation of the cavernous nerve (N = 12 per group). The penis was harvested and stained with Masson trichrome or antibody to TGF-β1, phospho-Smad2 (P-Smad2), smooth muscle α-actin, and factor VIII (N = 12 per group). Penis specimens from a separate group of animals were used for TGF-β1 enzyme-linked immunosorbent assay (ELISA), P-Smad2/Smad2, phospho-Smad3 (P-Smad3)/Smad3, fibronectin, collagen I, and collagen IV western blot, or hydroxyproline determination. Results Erectile function was significantly reduced in diabetic rats compared with that in controls. The expression of TGF-β1, P-Smad2, and P-Smad3 protein evaluated by ELISA or western blot was higher in diabetic rats than in controls. Compared with that in control rats, P-Smad2 expression was higher mainly in smooth muscle cells and fibroblasts of diabetic rats, whereas no significant differences were noted in endothelial cells or in the dorsal nerve bundle. Cavernous smooth muscle and endothelial cell contents were lower in diabetic rats than in controls. Cavernous fibronectin, collagen IV, and hydroxyproline content was significantly higher in diabetic rats than in controls. Conclusion Upregulation of TGF-β1 and activation of the Smad signaling pathway in the penis of diabetic rats might play important roles in diabetes-induced structural changes and deterioration of erectile function.

OBJECTIVEPatients with diabetic erectile dysfunction often have severe endothelial dysfunction and respond poorly to oral phosphodiesterase-5 inhibitors. We examined the effectiveness of the potent angiopoietin-1 (Ang1) variant, cartilage oligomeric matrix protein (COMP)-Ang1, in promoting cavernous endothelial regeneration and restoring erectile function in diabetic animals.RESEARCH DESIGN AND METHODSFour groups of mice were used: controls; streptozotocin (STZ)-induced diabetic mice; STZ-induced diabetic mice treated with repeated intracavernous injections of PBS; and STZ-induced diabetic mice treated with COMP-Ang1 protein (days −3 and 0). Two and 4 weeks after treatment, we measured erectile function by electrical stimulation of the cavernous nerve. The penis was harvested for histologic examinations, Western blot analysis, and cGMP quantification. We also performed a vascular permeability test.RESULTSLocal delivery of the COMP-Ang1 protein significantly increased cavernous endothelial proliferation, endothelial nitric oxide (NO) synthase (NOS) phosphorylation, and cGMP expression compared with that in the untreated or PBS-treated STZ-induced diabetic group. The changes in the group that received COMP-Ang1 restored erectile function up to 4 weeks after treatment. Endothelial protective effects, such as marked decreases in the expression of p47phox and inducible NOS, in the generation of superoxide anion and nitrotyrosine, and in the number of apoptotic cells in the corpus cavernosum tissue, were noted in COMP-Ang1–treated STZ-induced diabetic mice. An intracavernous injection of COMP-Ang1 completely restored endothelial cell-cell junction proteins and decreased cavernous endothelial permeability. COMP-Ang1–induced promotion of cavernous angiogenesis and erectile function was abolished by the NOS inhibitor, N-nitro-L-arginine methyl ester, but not by the NADPH oxidase inhibitor, apocynin.CONCLUSIONSThese findings support the concept of cavernous endothelial regeneration by use of the recombinant Ang1 protein as a curative therapy for diabetic erectile dysfunction.