Estimating meaningful change thresholds for Skin Pain-Numeric Rating Scale, Sleep-Numeric Rating Scale and Dermatology Life Quality Index in patients with prurigo nodularis.

BACKGROUND: Prurigo nodularis (PN) is characterized by intensely itchy nodules/lesions and skin pain, which can have a substantial impact on health-related quality of life (HRQoL). Treatment benefits on such symptoms and impacts are best assessed in trials using patient-reported outcome (PROs) instruments such as Skin Pain Numerical Rating Scale (NRS), Sleep-NRS and Dermatology Life Quality Index (DLQI). However, no guidance exists for interpreting meaningful changes in scores using these PROs in patients with PN. OBJECTIVES: The main objective was to derive within-patient (responder definition) and between-group improvement thresholds for interpreting Skin Pain-NRS, Sleep-NRS and DLQI total scores in patients with PN. The measurement properties of the three PROs were also evaluated. METHODS: Intention-to-treat (ITT), blinded and pooled data were used from the Phase 3 PRIME (NCT04183335) and PRIME2 (NCT04202679) studies evaluating the efficacy of dupilumab in adult patients with PN. Anchor- and distribution-based methods were applied to derive responder definition and between-group thresholds for Skin Pain-NRS, Sleep-NRS and DLQI. Data were additionally used to examine the instrument measurement properties, including reliability, validity and responsiveness. RESULTS: A total of 311 patients (mean age 49.5 years, 65.3% female) were included in the pooled ITT population. The within-patient improvement threshold for Skin Pain-NRS was estimated as 4.0 points, 2.0 points for Sleep-NRS and 9.0 points for DLQI total score. A 1.5-point improvement in Skin Pain-NRS scores, 1.0-point in Sleep-NRS and 4.0-point in DLQI indicated a between-group meaningful change. Adequate to good psychometric properties were demonstrated for all three instruments. CONCLUSIONS: The results of this study can aid interpretation of Skin Pain-NRS, Sleep-NRS and DLQI scores in patients with PN in both clinical trials and clinical practice to better understand and treat PN-related skin pain and the impact of PN on sleep quality and HRQoL.

Onychopapilloma: its clinical, dermoscopic and pathologic features.

BACKGROUND: Onychopapilloma is a benign tumour of the nail bed and distal matrix and commonly presents as longitudinal erythronychia, longitudinal leukonychia or longitudinal melanonychia. Because onychopapilloma is rare, its clinical characteristics and dermoscopic findings have not been well investigated in Asia. OBJECTIVES: This study aimed to investigate the clinical characteristics and dermoscopic and pathologic findings of onychopapilloma in Korea. METHODS: We retrospectively reviewed the medical records and clinical/dermoscopic photographs of 39 patients diagnosed with onychopapilloma in the Pusan National University Hospitals (Busan and Yangsan) for 11 years (2010-2021). RESULTS: Among 39 patients, 23 (59.0%) were men, and 16 (41.0%) were women. The mean age was 46.1 (16-77) years. All lesions were single, and most of them were located on the fingers (92.3%), especially the thumb (66.7%). The most common clinical feature was longitudinal erythronychia (56.4%), and the most common dermoscopic finding was distal subungual hyperkeratosis (100%). We found two new dermoscopic features: macrolunula and trailing lunula along the longitudinal band. Among 18 patients who underwent surgical excision, only 6 (33.3%) showed typical acanthosis and papillomatosis on the nail bed. CONCLUSIONS: We found that Asian onychopapilloma has similar clinicodermoscopic findings to the Caucasian one, that is to say, longitudinal erythronychia and distal subungual hyperkeratosis were the most common nail change and dermoscopic finding, respectively. We propose two new dermoscopic features of onychopapilloma: macrolunula and trailing lunula along the longitudinal band.

Antifungal activity of streptavidin C1 and C2 against pathogens causing Fusarium wilt.

Fusarium wilt is caused by the soil-inhabiting fungus Fusarium oxysporum ff. spp. and is one of the most devastating plant diseases, resulting in losses and decreasing the quality and safety of agricultural crops. We recently reported the structures and biochemical properties of two biotin-binding proteins, streptavidin C1 and C2 (isolated from Streptomyces cinnamonensis strain KPP02129). In the present study, the potential of the biotin-binding proteins as antifungal agent for Fusarium wilt pathogens was investigated using recombinant streptavidin C1 and C2. The minimum inhibitory concentration of streptavidin C2 was found to be 16 µg ml-1 for inhibiting the mycelial growth of F. oxysporum f.sp. cucumerinum and F. oxysporum f.sp. lycopersici, while that of streptavidin C1 was found to be 64 µg ml-1 . Compared with the nontreated control soil, the population density of F. oxysporum f.sp. lycopersici in the soil was reduced to 49·5% and 39·6% on treatment with streptavidin C1 (500 µg ml-1 ) and C2 (500 µg ml-1 ), respectively. A greenhouse experiment revealed that Fusarium wilt of tomato plants was completely inhibited on soil drenching using a 50-ml culture filtrate of the streptavidin-producing strain KPP02129.

PIN1 is a new therapeutic target of craniosynostosis.

Gain-of-function mutations in fibroblast growth factor receptors (FGFRs) cause congenital skeletal anomalies, including craniosynostosis (CS), which is characterized by the premature closure of craniofacial sutures. Apert syndrome (AS) is one of the severest forms of CS, and the only treatment is surgical expansion of prematurely fused sutures in infants. Previously, we demonstrated that the prolyl isomerase peptidyl-prolyl cis-trans isomerase interacting 1 (PIN1) plays a critical role in mediating FGFR signaling and that Pin1+/- mice exhibit delayed closure of cranial sutures. In this study, using both genetic and pharmacological approaches, we tested whether PIN1 modulation could be used as a therapeutic regimen against AS. In the genetic approach, we crossbred Fgfr2S252W/+, a mouse model of AS, and Pin1+/- mice. Downregulation of Pin1 gene dosage attenuated premature cranial suture closure and other phenotypes of AS in Fgfr2S252W/+ mutant mice. In the pharmacological approach, we intraperitoneally administered juglone, a PIN1 enzyme inhibitor, to pregnant Fgfr2S252W/+ mutant mice and found that this treatment successfully interrupted fetal development of AS phenotypes. Primary cultured osteoblasts from Fgfr2S252W/+ mutant mice expressed high levels of FGFR2 downstream target genes, but this phenotype was attenuated by PIN1 inhibition. Post-translational stabilization and activation of Runt-related transcription factor 2 (RUNX2) in Fgfr2S252W/+ osteoblasts were also attenuated by PIN1 inhibition. Based on these observations, we conclude that PIN1 enzyme activity is important for FGFR2-induced RUNX2 activation and craniofacial suture morphogenesis. Moreover, these findings highlight that juglone or other PIN1 inhibitors represent viable alternatives to surgical intervention for treatment of CS and other hyperostotic diseases.

Comparison of dermoscopic features between congenital and acquired acral melanocytic nevi in Korean patients.

BACKGROUND: The dermoscopic patterns of acral melanocytic nevi (AMNs) are crucial in differentiating them from acral melanoma. Several studies have reported the dermoscopic patterns of acquired acral melanocytic nevi (AAMNs). However, few have investigated the dermoscopic patterns of congenital acral melanocytic nevi (CAMNs). OBJECTIVE: To compare the clinical and dermoscopic features of CAMNs and AAMNs. METHODS: The present study included 43 patients with CAMNs and 40 with AAMNs. We reviewed their medical records as well as their clinical and dermoscopic findings. RESULTS: Congenital acral melanocytic nevis were more asymmetrical than AAMNs (P = 0.002) and presented more frequently as comma-shaped (P = 0.005). Regarding dermoscopic findings, globular pattern (55.8%) was the most common feature of CAMNs, while parallel furrow pattern (37.5%) was the most common feature of AAMNs. The presence of fibrillar, globular, and parallel ridge patterns, and diffuse multi-component pigmentation differed significantly between the groups (P < 0.05). Furthermore, CAMNs showed melanoma-specific dermoscopic patterns, such as parallel ridge (18.6%) and diffuse multi-component pigmentation (25.6%). CONCLUSION: The dermoscopic patterns of CAMNs and AAMNs differed markedly. In terms of dermoscopic patterns, CAMNs resembled acral melanoma more often than AAMNs did.

Comparative outcomes of robot-assisted minimally invasive versus open esophagectomy in patients with esophageal squamous cell carcinoma: a propensity score-weighted analysis.

Robots are increasingly used in minimally invasive surgery. We evaluated the clinical benefits of robot-assisted minimally invasive esophagectomy (RAMIE) in comparison with the conventional open esophageal surgery. From 2012 to 2016, 371 patients with esophageal squamous cell carcinoma underwent an Ivor Lewis or McKeown procedure at our institution. Of these, 130 patients underwent laparoscopic gastric conduit formation followed by RAMIE, whereas 241 patients underwent conventional esophageal surgery, including laparotomy and open esophagectomy (OE). We compared the short- and long-term clinical outcomes of these patients using the propensity score-based inverse probability of treatment weighting technique (IPTW). Among the early outcomes, the OE group showed a higher incidence of pneumonia (P = 0.035) and a higher requirement for vasopressors (P = 0.001). Regarding the long-term outcomes, all-cause mortality was significantly higher (P = 0.001) and disease-free survival was lower (P = 0.006) in the OE group. Wound-related problems also occurred more frequently in the OE group (P = 0.020) during the long-term follow-up. There was no statistical intergroup difference in the recurrence rates (P = 0.191). The Cox proportional-hazard analysis demonstrated that wound problems (HR 0.16, 95% CI 0.02-0.57; P = 0.017), pneumonia (HR 0.23, 95% CI 0.06-0.68; P = 0.019), and use of vasopressors (HR 0.14, 95% CI 0.08-0.25; P = 0.001) were independent predictors of mortality. RAMIE could be a better surgical option for selected patients with esophageal squamous cell carcinoma.

Large anomalous Hall current induced by topological nodal lines in a ferromagnetic van der Waals semimetal.

Topological semimetals host electronic structures with several band-contact points or lines and are generally expected to exhibit strong topological responses. Up to now, most work has been limited to non-magnetic materials and the interplay between topology and magnetism in this class of quantum materials has been largely unexplored. Here we utilize theoretical calculations, magnetotransport and angle-resolved photoemission spectroscopy to propose Fe3GeTe2, a van der Waals material, as a candidate ferromagnetic (FM) nodal line semimetal. We find that the spin degree of freedom is fully quenched by the large FM polarization, but the line degeneracy is protected by crystalline symmetries that connect two orbitals in adjacent layers. This orbital-driven nodal line is tunable by spin orientation due to spin-orbit coupling and produces a large Berry curvature, which leads to a large anomalous Hall current, angle and factor. These results demonstrate that FM topological semimetals hold significant potential for spin- and orbital-dependent electronic functionalities.

Protective effects of extracorporeal shockwave on rat chondrocytes and temporomandibular joint osteoarthritis; preclinical evaluation with in vivo99mTc-HDP SPECT and ex vivo micro-CT.

OBJECTIVE: Extracorporeal shockwave therapy (ESWT) has been shown to have chondroprotective effects on arthritic diseases. We investigated the effects of ESWT on temporomandibular joint osteoarthritis (TMJOA) using rat chondrocytes and TMJOA rat models. DESIGN: Cell viability and expression of pro-inflammatory cytokines, cartilage degradation, and apoptosis markers were measured in control, monosodium iodoacetate (MIA)-treated and ESWT plus MIA-treated chondrocytes in vitro, and intra-articular MIA injection (TMJOA) and ESWT on TMJOA rats in vivo. In vivo99mTc-hydroxymethylene diphosphonate (HDP) single-photon emission computerized tomography/computerized tomography (SPECT/CT) and ex-vivo micro-CT and histologic examinations were performed in rat models. RESULTS: ESWT plus MIA-treated chondrocytes showed increased cell viability significantly (P = 0.007), while decreased genetic expression of pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6); P < 0.001 for each] and cartilage degradation markers [matrix metalloproteinase-3 (MMP3), matrix metalloproteinase-13 (MMP13), and bone morphogenetic protein 7 (BMP7); P < 0.001 for each], and number of apoptotic cells (P < 0.001) compared to MIA-treated chondrocytes. Changes in cytochrome c and cleaved caspase-3 levels relative to procaspase-3 were decreased over MIA-treated chondrocytes. ESWT on TMJOA rat models was associated with a significant decrease in pro-inflammatory and cartilage degradation markers, as demonstrated by real-time PCR and immunohistochemistry stains (P < 0.001 for each). On 99mTc-HDP SPECT/CT, the ESWT group showed a significantly lower uptake ratio compared to the TMJOA group (P = 0.008). Micro-CT analysis revealed that the ESWT group showed improved structure and bone quality compared to the TMJOA control group. CONCLUSIONS: ESWT was associated with a protective effect on cartilage and subchondral bone structures of TMJOA by reducing inflammation, cartilage degradation, and chondrocyte apoptosis.

Length of hospital stay after hip fracture surgery and 1-year mortality.

There is ongoing effort to discharge patients early after hip fracture surgery to reduce the medical and economic burden. We tried to find whether there is any related side effect, and discovered that early discharge, especially before 10 days after surgery, is associated with higher mortality. INTRODUCTION: The aim of this study was to analyze the association between the length of hospital stay after hip fracture and 1-year mortality in older adults aged ≥ 65 years old. METHODS: We conducted a retrospective cohort study using the Korean National Health Insurance Service data to identify patients who were discharged after hip fracture surgery from 2007 to 2009 among 487,460 older adults of age ≥ 65 years. The lengths of stay involving hip fracture surgery were categorized at 10-day interval, and analyzed in relation to 1-year mortality from the date of hospital discharge. RESULTS: A total of 4213 patients were discharged after hip fracture surgery, of whom 604 (14.3%) died within 1 year of discharge. The average length of stay was 30.7 days (standard deviation 24.5 days). The 1-year mortality was the highest for the length of stay ≤ 10 days group at 21.7%, followed by 15.2%, 14.3%, 13.3%, and 12.4% for > 40, 21-30, 31-40, and 11-20 days groups, respectively (p value 0.05). On Cox proportional hazard regression, the adjusted hazard ratio for length of stay ≤ 10 days group was 1.56 (95% confidence interval 1.14-2.12) against the reference group (11-20 days), while other groups did not show statistical significance. Higher risk of death was associated with increasing age, male gender, Charlson comorbidity index ≥3, subtrochanteric fracture, and discharge to tertiary care hospitals and long-term care hospitals. CONCLUSION: Older adults discharged within 10 days of hospital admission for hip fracture surgery have higher 1-year mortality after discharge.

Different functional genes of upper airway microbiome associated with natural course of childhood asthma.

BACKGROUND: Microbial colonization of the airway plays a role in the pathogenesis of asthma; however, the effect of the upper airway microbiome on childhood asthma is not fully understood. We analyzed the metagenome of airway microbiome to understand the associated role of upper airway microbiome with the natural course of childhood asthma. METHODS: Nasopharyngeal swabs were collected from children with asthma, those in asthma remission, and control groups. High-throughput sequencing was used to examine the structure and functional dynamics of the airway microbiome with respect to asthma phenotypes. RESULTS: The composition of microbiota differed among healthy control, asthma, and remission groups. The relative abundance of Streptococcus was negatively associated with FEV1% predicted (P = .023) and that of Staphylococcus was negatively associated with methacholine PC20 (P = .013). Genes related to arachidonic acid metabolites, lysine residues, and glycosaminoglycans in the microbiome could be associated with airway inflammation. In particular, genes related to synthesis of anti-inflammatory prostaglandin E2 (PGE2 ) were not detected from the airway microbiome in the asthma group. CONCLUSIONS: These data suggest that alterations in the composition and function of the upper airway microbiome could be related with the natural course of asthma in children.

Functional characterization of O-methyltransferases used to catalyse site-specific methylation in the post-tailoring steps of pradimicin biosynthesis.

AIMS: To identify the roles of the two O-methyltransferase homologous genes pdmF and pdmT in the pradimicin biosynthetic gene cluster of Actinomadura hibisca P157-2. METHODS AND RESULTS: Pradimicins are pentangular polyphenol antibiotics synthesized by bacterial type II polyketide synthases (PKSs) and tailoring enzymes. Pradimicins are naturally derivatized by combinatorial O-methylation at two positions (i.e., 7-OH and 11-OH) of the benzo[α]naphthacenequinone structure. PdmF and PdmT null mutants (PFKO and PTKO) were generated. PFKO produced the 11-O-demethyl shunt metabolites 11-O-demethylpradimicinone II (1), 11-O-demethyl-7-methoxypradimicinone II (2), 11-O-demethylpradimicinone I (3) and 11-O-demethylpradimicin A (4), while PTKO generated the 7-O-demethyl derivatives pradimicinone II (5) and 7-hydroxypradimicin A (6). Pradimicinones 1, 2, 3, and 5 were fed to a heterologous host Escherichia coli harbouring expression plasmid pET-22b::pdmF or pET-28a::pdmT. PdmF catalysed 11-O-methylation of pradimicinones 1, 2, and 3 regardless of O-methylation at the C-7 position, while PdmT was unable to catalyse 7-O-methylation when the C-11 hydroxyl group was methylated (5). CONCLUSIONS: PdmF and PdmT were involved in 11-O- and 7-O-methylations of the benzo[α]naphthacenequinone moiety of pradimicin, respectively. Methylation of the C-7 hydroxyl group precedes methylation of the C-11 hydroxyl group in pradimicin biosynthesis. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first reported demonstration of the functions of PdmF and PdmT for regiospecific O-methylation, which contributes to better understanding of the post-PKS modifications in pradimicin biosynthesis as well as to rational engineering of the pradimicin biosynthetic machinery.

The importance of dermoscopy for the diagnosis of acquired bilateral telangiectatic macules: the angioid streak pattern reveals underlying chronic liver disease.

BACKGROUND: Acquired bilateral telangiectatic macules (ABTM) are a newly recognized disease entity, which manifest as multiple telangiectatic pigmented macules confined mostly to the upper arms. OBJECTIVES: To evaluate clinical and dermoscopic features in a group of 50 patients with ABTM and to determine the diagnostic usefulness of dermoscopy in ABTM. METHODS: Patients were selected from two tertiary teaching hospitals in Korea [Pusan National University Hospitals (Busan and Yangsan)]. Fifty patients (41 males and 9 females; mean age 48.1 years; range 26-78 years) with ABTM were included in the study. The dermoscopic findings were graded using a 4-point scale: none (0), mild (1), moderate (2) and severe (3). In addition, the results of 23 patients with and 27 patients without chronic liver disease (CLD) were compared to determine whether the presence of CLD affects dermoscopic findings. RESULTS: Three distinct dermoscopic patterns were observed; brown pigmentations, telangiectasia (linear-irregular vessels) and an angioid streak pattern. Brown pigmentation in the group without CLD had higher severity score than those in CLD group (mean score: 2.00 vs. 1.48, P = 0.033). However, mean telangiectasia severity score was higher in the CLD group (2.14 vs. 1.39, P < 0.001). The angioid streak pattern was more severe and more common in patients with CLD than in those without [1.37 vs. 0.35 (P < 0.001) and 63.0% vs. 26.1%, respectively]. CONCLUSIONS: Detailed observations with dermoscopy can provide first clues of the presence of ABTM and underlying chronic liver disease.

Alitretinoin can be a good treatment option for idiopathic recalcitrant trachyonychia in adults: an open-label study.

BACKGROUND: Trachyonychia can be refractory to conventional treatments including topical, intralesional or systemic corticosteroids, as well as cyclosporine and retinoids. Therefore, new treatment options are needed for recalcitrant trachyonychia. OBJECTIVE: To evaluate the efficacy and safety of oral alitretinoin for idiopathic recalcitrant trachyonychia. METHODS: A total of 21 adult patients with 210 nails affected by idiopathic recalcitrant trachyonychia were evaluated in this open-label prospective study. All patients took 30 mg of alitretinoin daily for at least 3 months. Clinical outcomes were assessed using the Physician Global Assessment (PGA) scale proposed by Park et al. (degree of roughness: 0, clear; 1, mild; 2, moderate; 3, marked; 4, severe) at baseline and 1, 3 and 6 months after treatment. RESULTS: After 1, 3 and 6 months of treatment, 74.3% (123/210), 98.1% (206/210) and 99.2% (119/120) of nails showed clinical improvement, respectively; 0% (0/210), 22.9% (48/210) and 69.2% (83/120) were completely free from nail abnormalities. The mean PGA score at baseline was 3.4, decreasing significantly to 2.7, 1.3 and 0.7 at 1, 3 and 6 months following treatment, respectively. LIMITATIONS: A small number of participants and lack of a control group were limitations. CONCLUSIONS: For the first time, this study evaluated the efficacy and safety of oral alitretinoin for idiopathic recalcitrant trachyonychia in adults. The results suggest that oral alitretinoin can be a good treatment option for adult patients with recalcitrant trachyonychia.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study).

BACKGROUND: Psychological aspect and quality of life should be considered in treating patients with psoriasis. OBJECTIVE: We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis. METHODS: The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ). RESULTS: Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental). CONCLUSION: The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

The clinical and histopathological characteristics of early-onset basal cell carcinoma in Asians.

BACKGROUND: Basal cell carcinoma (BCC) is by far the most common cancer in white populations. In addition, recent reports have demonstrated an increasing incidence of BCC in Korea. We have observed a significant number of early-onset BCC cases in which the disease occurred in patients younger than 50 years. OBJECTIVE: To investigate the clinicopathological characteristics of early-onset BCC in an Asian population, specifically in Koreans. METHODS: One hundred and five patients with early-onset BCC were enrolled from a total of 1047 BCC patients who underwent surgery between January 1997 and December 2014 (942 patients over the age of 50 years were designated as the control group). RESULTS: Early-onset BCC accounted for 10.03% of all 1047 cases and the incidence over time displayed an incremental trend. The early-onset group displayed similar results as the control group, with a predominance of female BCC patients and the majority of tumours displaying the following characteristics: small in size, occurring in sun-exposed areas and belonging to the noduloulcerative clinical subtype and nodular histopathological subtype. In comparison with a previous study in a Western population, the incidence of the disease in non-exposed areas of the body, as well as the proportion of tumours of the superficial histological subtype, were lower in Asian patients. CONCLUSION: Although the clinicopathological characteristics of BCC are well-known, these characteristics have not been determined for early-onset BCC in an Asian population. Therefore, this study is the first report on early-onset BCC in Asians, specifically in a Korean patient group.

Antifungal activity of rimocidin and a new rimocidin derivative BU16 produced by Streptomyces mauvecolor BU16 and their effects on pepper anthracnose.

AIMS: The objective of this study was to explore antifungal metabolites targeting fungal cell envelope and to evaluate the control efficacy against anthracnose development in pepper plants. METHODS AND RESULTS: A natural product library comprising 3000 microbial culture extracts was screened via an adenylate kinase (AK)-based cell lysis assay to detect antifungal metabolites targeting the cell envelope of plant-pathogenic fungi. The culture extract of Streptomyces mauvecolor strain BU16 displayed potent AK-releasing activity. Rimocidin and a new rimocidin derivative, BU16, were identified from the extract as active constituents. BU16 is a tetraene macrolide containing a six-membered hemiketal ring with an ethyl group side chain instead of the propyl group in rimocidin. Rimocidin and BU16 showed broad-spectrum antifungal activity against various plant-pathogenic fungi and demonstrated potent control efficacy against anthracnose development in pepper plants. CONCLUSIONS: Antifungal metabolites produced by S. mauvecolor strain BU16 were identified to be rimocidin and BU16. The compounds displayed potent control efficacy against pepper anthracnose. SIGNIFICANCE AND IMPACT OF THE STUDY: Rimocidin and BU16 would be active ingredients of disease control agents disrupting cell envelope of plant-pathogenic fungi. The structure and antifungal activity of rimocidin derivative BU16 is first described in this study.

Artefacts at a glance: differentiating features of artefactual stenosis from true stenosis at the genu of the petrous internal carotid artery on TOF MRA.

AIM: To investigate the distinguishing features of artefactual stenosis from true stenosis at the genu of the petrous internal carotid artery (ICA) on time of flight (TOF) magnetic resonance angiography (MRA). MATERIALS AND METHODS: Both TOF MRA and digital subtraction angiography (DSA) were performed in 65 patients with 74 vessels who demonstrated artefactual stenosis in 43 patients with 50 vessels and true stenosis in 22 patients with 24 vessels. The following findings of the signal loss were compared between the two groups: (1) margin, (2) darkness, (3) the presence of bilaterality, (4) the presence of tandem arterial stenosis, (5) the location of the epicentre, and (6) length. RESULTS: In five out of the six evaluated items, statistically significant differences were present between the two groups (p<0.00 in all five items). Artefactual stenosis more frequently showed signal loss with ill-defined margins (47/50), less darkness compared to the background darkness (46/50), the absence of tandem arterial stenosis (35/50), epicentre at the genu (34/50), and shorter length (2.57 ± 0.68 mm). No significant difference was noted in the presence of bilaterality of signal loss between the two groups (p=0.706). CONCLUSION: Several MRA features can be useful for suggesting artefactual stenosis rather than true stenosis at the genu of the petrous ICA on TOF MRA.

Mandibular second molar root canal morphology and variants in a Korean subpopulation.

AIM: To determine the root canal anatomy of mandibular second molars in a Korean population by analysing cone-beam computed tomography (CBCT) images. METHODOLOGY: The CBCT images of 960 subjects were examined. The number and configuration of roots and canals were categorized according to Vertucci's and modified Melton's classifications. RESULTS: Of the 1920 mandibular second molars, 41% had one root, 58% had two roots, and <1% had three roots. In the mesial roots of two-rooted molars, Vertucci's Type lV (44%) and Type II (37.75%) canals were most frequent. The prevalence of C-shaped roots was 40%, and C-shaped roots in combination with additional mesiolingual or distolingual roots were found in <1% of molars. Interestingly, O-shaped canals were detected in 0.10% of the molars. Of the C-shaped roots, the most common configuration types were Melton's Type I (66%) in the coronal region and Melton's Type III (56%) in the apical region. The prevalence of C-shaped roots was higher in females (47%) than in males (32%) (P < 0.001) and did not differ with age (P = 0.497) or tooth position (P = 0.514). Most (82%) C-shaped canals were bilateral (P < 0.001). CONCLUSIONS: A high prevalence of C-shaped canals and a low incidence of three-rooted molars were observed in the mandibular second molars of the Korean subpopulation studied.

Purification and characterization of a melanin biodegradation enzyme from Geotrichum sp.

OBJECTIVE: Melanin is a black or brown phenolic polymer present mainly in skin and hair. Although melanin can be degraded by some microbial species, the melanin degradation capacity of Geotrichum sp. is unknown. The aim of this study was to characterize a melanin biodegradation enzyme from Geotrichum sp. METHODS: In this study, we assessed the melanin degradation activity of Geotrichum sp. in comparison with the major melanin-degrading enzymes, manganese-dependent peroxidase (MnP), manganese-independent peroxidase, lignin peroxidase and laccase. Furthermore, the effect of several carbohydrates on melanin degradation by Geotrichum sp. was determined. The MnP enzyme was purified using ammonium sulphate precipitation and Sephadex G-200 column chromatography, and then the conditions for optimal enzymatic activity were determined by adjusting the pH, temperature and Tween-80 concentration. RESULTS: Compared with extracellular ligninolytic enzymes of Geotrichum sp., MnP had the highest ligninolytic enzyme activity; and the highest enzymatic activity was observed in the presence of glucose. The final purified MnP enzyme exhibited 6 U mL-1 activity and had a molecular weight of 54.2 kDa. The enzymatic activity was highest at pH 4.5 and 25-35°C in the absence of Tween-80. CONCLUSION: These results indicate the potential of MnP purified from Geotrichum sp. as a skin-lightening agent in the cosmetic industry.