Biotransformation and detoxification of tetrabromobisphenol A by white-rot fungus Phanerochaete sordida YK-624.

The bulky phenolic compound tetrabromobisphenol A (TBBPA) is a brominated flame retardant used in a wide range of products; however, it diffuses into the environment, and has been reported to have toxic effects. Although it is well-known that white-rot fungi degrade TBBPA through ligninolytic enzymes, no other metabolic enzymes have yet been identified, and the toxicity of the reaction products and their risks have not yet been examined. We found that the white-rot fungus Phanerochaete sordida YK-624 converted TBBPA to TBBPA-O-ß-D-glucopyranoside when grown under non-ligninolytic-enzyme-producing conditions. The metabolite showed less cytotoxicity and mitochondrial toxicity than TBBPA in neuroblastoma cells. From molecular biological and genetic engineering experiments, two P. sordida glycosyltransferases (PsGT1c and PsGT1e) that catalyze the glycosylation of TBBPA were newly identified; these enzymes showed dramatically different glycosylation activities for TBBPA and bisphenol A. The results of computational analyses indicated that the difference in substrate specificity is likely due to differences in the structure of the substrate-binding pocket. It appears that P. sordida YK-624 takes up TBBPA, and reduces its cytotoxicity via these glycosyltransferases.

Structural health monitoring of sabo check dams with cosmic-ray muography.

Debris dams have a crucial role in consolidation of river basins and allow erosion control, flood protection in mountainous areas. Many of these infrastructures have operated over five decades, thus structural health monitoring (SHM) of these infrastructures became timely due to their aging. Utilizing new techniques is required for inspecting a large number of dams and deciding about their reinforcement or reconstruction. In this work, we propose cosmic-ray muography as a complementary tool for the SHM of debris dams. We conducted the first muographic surveying of a sabo check dam in the Karasu River, Gunma, Japan. The average mass density image was produced with a spatial resolution of 0.5 m through the dam. The comparison of density data reconstructed by muography and gamma-ray logging suggest the internal deterioration of dam in the region where cement released out from the embankment body.

Aerobic H2 production related to formate metabolism in white-rot fungi.

Biohydrogen is mainly produced by anaerobic bacteria, anaerobic fungi, and algae under anaerobic conditions. In higher eukaryotes, it is thought that molecular hydrogen (H2) functions as a signaling molecule for physiological processes such as stress responses. Here, it is demonstrated that white-rot fungi produce H2 during wood decay. The white-rot fungus Trametes versicolor produces H2 from wood under aerobic conditions, and H2 production is completely suppressed under hypoxic conditions. Additionally, oxalate and formate supplementation of the wood culture increased the level of H2 evolution. RNA-seq analyses revealed that T. versicolor oxalate production from the TCA/glyoxylate cycle was down-regulated, and conversely, genes encoding oxalate and formate metabolism enzymes were up-regulated. Although the involvement in H2 production of a gene annotated as an iron hydrogenase was uncertain, the results of organic acid supplementation, gene expression, and self-recombination experiments strongly suggest that formate metabolism plays a role in the mechanism of H2 production by this fungus. It is expected that this novel finding of aerobic H2 production from wood biomass by a white-rot fungus will open new fields in biohydrogen research.

Ergosterol and Its Metabolites Induce Ligninolytic Activity in the Lignin-Degrading Fungus Phanerochaete sordida YK-624.

White-rot fungi are the most important group of lignin biodegraders. Phanerochaete sordida YK-624 has higher ligninolytic activity than that of model white-rot fungi. However, the underlying mechanism responsible for lignin degradation by white-rot fungi remains unknown, and the induced compounds isolated from white-rot fungi for lignin degradation have never been studied. In the present study, we tried to screen ligninolytic-inducing compounds produced by P. sordida YK-624. After large-scale incubation of P. sordida YK-624, the culture and mycelium were separated by filtration. After the separation and purification, purified compounds were analyzed by high-resolution electrospray ionization mass spectrometry and nuclear magnetic resonance. The sterilized unbleached hardwood kraft pulp was used for the initial evaluation of ligninolytic activity. Ergosterol was isolated and identified and it induced the lignin-degrading activity of this fungus. Moreover, we investigated ergosterol metabolites from P. sordida YK-624, and the ergosterol metabolites ergosta-4,7,22-triene-3,6-dione and ergosta-4,6,8(14),22-tetraen-3-one were identified and then chemically synthesized. These compounds significantly improved the lignin-degrading activity of the fungus. This is the first report on the ligninolytic-inducing compounds produced by white-rot fungi.

Construction of white-rot fungal-bacterial consortia with improved ligninolytic properties and stable bacterial community structure.

It is believed that wood-rot fungi change their wood decay activities due to influences from co-existing bacterial communities; however, it is difficult to elucidate experimentally the interaction mechanisms in fungal-bacterial consortia because the bacterial community structure is quite unstable and readily changes. Indeed, the wood decay properties of fungal-bacterial consortia consisting of a white-rot fungus Phanerochaete sordida YK-624 and a natural bacterial community changed dramatically during several sub-cultivations on wood. Therefore, development of a sub-cultivation method that imparts stability to the bacterial community structure and fungal phenotype was attempted. The adopted method using agar medium enabled maintenance of fungal phenotypes relating to wood decay and the bacterial community even through dozens of repetitive sub-cultures. Some bacterial metabolic pathways identified based on gene predictions were screened as candidates involved in P. sordida-bacterial interactions. In particular, pathways related to prenyl naphthoquinone biosynthesis appeared to be involved in an interaction that promotes higher lignin degradation selectivity by the consortia, as naphthoquinone derivatives induced phenol-oxidizing activity. Based on these results, it is expected that detailed analyses of the relationship between the wood-degrading properties of white-rot fungal-bacterial consortia and bacterial community structures will be feasible using the sub-cultivation method developed in this study.

SUBRETINAL ENDOSCOPIC SURGERY FOR METASTATIC CHOROIDAL TUMOR.

PURPOSE: To report a case of a metastatic choroidal tumor treated with subretinal endoscopic surgery. METHODS: A single case report. RESULTS: A 68-year-old woman presented with a metastatic choroidal tumor in the right eye and an intraocular pressure of 54 mmHg. Chemotherapy and radiotherapy were ineffective in eliminating her eye pain. Subretinal endoscopic surgery was performed to remove the metastatic choroidal tumor with the complex retinal detachment attached to the posterior surface of the lens. The day after subretinal endoscopic surgery, the patient's intraocular pressure decreased to 7 mmHg and her pain subsided. The chemotherapeutic strategy was modified according to the pathological findings. Survival prognosis improved from 3 to 18 months. Twenty-one months after the surgery, the retinal detachment was reattached under silicone oil with a best-corrected visual acuity of 20/1,000 and an intraocular pressure of 15 mmHg. CONCLUSION: In this case, subretinal endoscopic surgery preserved visual function, eliminating the need for enucleation.

The complete mitochondrial genome of the white-rot fungus Phanerochaete sordida YK-624.

The white-rot fungus Phanerochaete sordida (Karsten) Eriksson and Ryvarden 1978 is known for its excellent ligninolytic activity and capability to degrade various recalcitrant organic pollutants. In this study, we determined the complete mitochondrial genome sequence of P. sordida YK-624. The mitochondrial genome is 129,567 bp in length with a GC content of 28.9%, and contains two ribosomal RNA genes, 26 transfer RNA genes, and 50 open reading frames, including 14 conserved proteins. Phylogenetic analysis based on the mitochondrial genome confirmed that P. sordida belongs to the family Phanerochaetaceae in the order Polyporales, and showed the general phylogenetic relationships.

Ethanol fermentation by saprotrophic white-rot fungus Phanerochaete sordida YK-624 during wood decay as a system for short-term resistance to hypoxic conditions.

In this study, major factors involved in regulating ethanol production from wood by the saprotrophic white-rot fungus Phanerochaete sordida YK-624 were investigated. P. sordida YK-624 produced ethanol from wood meal culture without the addition of any nutrients, and ethanol was produced from wood culture only when the oxygen concentration in headspace was reduced to ≤5%; thereafter, ethanol production ceased within a few days. Analyses of gene expression during aerobic incubation indicated that P. sordida simultaneously upregulates the glycolytic pathway from sugar uptake to pyruvate conversion during ethanol fermentation and suppresses pyruvate influx into the TCA cycle. Upon termination of ethanol fermentation, the expression of all tested genes was repressed, and the fungus ceased to grow. In contrast, the fungus could utilize ethanol for aerobic growth. These results suggest that ethanol fermentation by P. sordida functions as a short-term stress response system under anaerobic conditions during wood decay, enabling the fungus to rapidly resume growing when oxygen is supplied (e.g., following breakdown of plant cell walls or removal of the fungus from water immersion). This is the first report to describe the physiologic significance of ethanol fermentation in saprotrophic white-rot fungi.

Draft Genome Sequence of the White-Rot Fungus Phanerochaete sordida YK-624.

Here, we report the draft genome sequence of the white-rot basidiomycete fungus Phanerochaete sordida YK-624 (ATCC 90872), which was isolated in Yakushima, Kagoshima, Japan. The genome of this strain was found to be 41.2 Mbp, with a G+C content of 58.7%, and to comprise 17,108 predicted protein-coding sequences.

Closed total talar dislocation without fracture in a rare college athlete case.

Total talar dislocation without a fracture is an extremely rare injury. It is often the result of high-energy trauma, such as that incurred after a fall, or owing to motor or vehicular accidents. Talar dislocations have poor outcomes owing to the frequent complications of infection, avascular necrosis and osteoarthritis attributed to open dislocations. We report herein a closed total talar dislocation without a fracture in a college athlete who was injured during sports activities. Specifically, a 20-year-old man was injured during a soccer game this led to a closed total talar dislocation. We performed closed reduction with image guidance subject to a popliteal sciatic nerve block, and placed a plaster cast below the knee. Radiographic studies after reduction revealed no associated fractures. After an eight week no-weight bearing period, we confirmed that there were no avascular necrosis signs on magnetic resonance images. Based on these findings, partial weight bearing was allowed. At 18 months post trauma, the athlete continues to play soccer despite the fact that he experiences a slight pain and limited range of motion. The blood supply to the talus is limited, and trauma, such as dislocation, can easily injure the blood supply, thus resulting in complications, such as avascular necrosis. The talus vascularity of the presented case was maintained by superior branches. We think that it is important to a) perform closed reduction early on, b) avoid any type of surgical operation that damages the limited talus blood supply, and c) allow weight bearing after the lack of avascular necrosis signs is confirmed. Although there is no standardized treatment, the talar dislocation treatment should be chosen to preserve the blood supply to the talus as much as possible.

Transcriptomics analysis reveals the high biodegradation efficiency of white-rot fungus Phanerochaete sordida YK-624 on native lignin.

Lignocellulosic biomass is an organic matrix composed of cellulose, hemicellulose, and lignin. In nature, lignin degradation by basidiomycetes is the key step in lignocellulose decay. The white-rot fungus Phanerochaete sordida YK-624 (YK-624) has been extensively studied due to its high lignin degradation ability. It was demonstrated that YK-624 can secrete lignin peroxidase and manganese peroxidase for lignin degradation. However, the underlying mechanism for lignin degradation by YK-624 remains unknown. Here, we analyzed YK-624 gene expression following growth under ligninolytic and nonligninolytic conditions and compared the differentially expressed genes in YK-624 to those in the model white-rot fungus Phanerochaete chrysosporium by next-generation sequencing. More ligninolytic enzymes and lignin-degrading auxiliary enzymes were upregulated in YK-624. This might explain the high degradation efficiency of YK-624. In addition, the genes involved in energy metabolism pathways such as the TCA cycle, lipid metabolism, carbon metabolism and glycolysis were upregulated under ligninolytic conditions in YK-624. The first differential gene expression analysis of YK-624 under ligninolytic and nonligninolytic conditions was reported in this study. The results obtained in this study indicated that YK-624 produces more enzymes involved in lignin degradation and energy metabolism.

Clinical Outcomes of Endoscope-Assisted Vitreous Surgery for Giant Retinal Tear Detachment.

INTRODUCTION: With the advent of perfluorocarbon liquid (PFCL), the success rate of refractory giant retinal tear (GRT) detachment has dramatically improved. PFCL is a very effective tool when used properly, but in GRT detachment, it may move under the retina through the tear, so it is necessary to devise ways to prevent PFCL from migrating under the retina. Ophthalmic endoscope-assisted vitrectomy may reduce the risk of subretinal migration of PFCL, facilitate safer use of PFCL, and increase the success rate of GRT detachment. The present study aimed to describe the clinical outcomes of endoscope-assisted vitreous surgery for giant retinal detachment. METHODS: Twenty consecutive eyes from 19 patients who had undergone endoscope-assisted vitreous surgery for treatment of a GRT detachment were enrolled. Subretinal fluid drainage, extension of the rolled GRT, and endophotocoagulation under air were performed with the aid of an endoscope, without the use of PFCL. Where necessary, extension of a fixed retinal fold and internal limiting membrane peeling was performed with PFCL. RESULTS: The initial and final retinal reattachment rates were 90 and 95%, respectively. In 3 eyes, a small amount of PFCL was used, and there were no PFCL remnants. The mean follow-up duration was 18 months (range, 3-69 months). After surgery, the mean best-correlated visual acuity significantly improved from 20/514 to 20/41 (p = 0.0008). DISCUSSION/CONCLUSION: Endoscope-assisted vitreous surgery for giant retinal detachment has favourable clinical outcomes for visual acuity and retinal detachment.

Improvement of saccharide yield from wood by simultaneous enzymatic delignification and saccharification using a ligninolytic enzyme and cellulase.

White-rot fungi are thought to hold promise for development of a delignification pretreatment process for wood biorefinery that is less energy-consuming than current processes. However, the reaction must take place over weeks and consumes non-neglectable amounts of saccharides. To establish a biological process for wood biorefinery would first require establishment of an enzymatic approach to delignification. Such an approach has the potential to lower costs and reduce saccharide loss. Here, we attempted enzymatic delignification reactions using manganese peroxidases (MnP), a lignin-degrading enzyme, under several reaction conditions. The delignification rate from beech wood meal (particle size <45 µm) of up to 11.0% in 48 h was reached in a MnP reaction supplemented with multiple co-oxidants, glucose, glucose oxidase (GOD) and commercial cellulase. An additional 48-h reaction using fresh MnP/co-oxidants increased the delignification rate to 14.2%. Simultaneous enzymatic delignification and saccharification, which occurs without a need for glucose supplementation, successfully improved the glucose yield to 160% of the reaction without MnP. Development of a more accurate imitation of the mechanisms of delignification that occurs in white-rot fungi has the potential to improve the monosaccharide yield resulting from simultaneous delignification and saccharification.

Differences in the Knowledge and Experience of Physicians and Dentists About Medication-Related Osteonecrosis of the Jaw in Osteoporotic Patients.

AIM: Prevention of medication-related osteonecrosis of the jaw (MRONJ) in patients with osteoporosis requires the cooperation of physicians and dentists. We investigated the knowledge, experience, and behaviour related to medical and dental cooperation for MRONJ prevention in patients with osteoporosis between physicians and dentists practising in the Shiga prefecture. MATERIALS AND METHODS: We conducted a cross-sectional study to investigate the cooperation between practising physicians and dentists for preventing osteonecrosis of the jaw (ONJ) in patients with osteoporosis using 2 separate questionnaires from July 28, 2018, to February 3, 2019. RESULTS: Of 461 dentists who were sent the questionnaires at their dental clinics, 307 (67%) responded via fax. Of 846 physicians who were sent the questionnaire at their clinics, 378 (45%) responded via fax. Of these, 268 (32%) were finally analysed because 110 (13%) physicians had never treated patients with osteoporosis; 50% dentists and 24% physicians were familiar with the MRONJ position paper in Japan, and 39% dentists and 9% physicians had encountered MRONJ in their clinical practice. A total of 30% physicians had requested oral health care by a dentist before administering bone-modifying agents (BMA) therapy. The knowledge and experience of MRONJ differed between physicians and dentists. CONCLUSION: The behaviour of physicians and dentists was insufficient to enable medical and dental cooperation for the prevention of MRONJ in patients with osteoporosis. The lack of cooperation between physicians and dentists during osteoporosis treatment in the Shiga prefecture in Japan is documented in this study.

Seasonal Differences in the UVA/UVB Ratio of Natural Sunlight Influence the Efficiency of the Photoisomerization of (6-4) Photoproducts into their Dewar Valence Isomers.

The UVA and UVB components of sunlight can produce three classes of bipyrimidine DNA photolesions [cyclobutane pyrimidine dimers (CPDs), pyrimidine (6-4) pyrimidone photoproducts (6-4PPs) and related Dewar valence isomers (DewarPPs)]. The UVA/UVB ratio of sunlight is high in winter and low in summer in the Northern Hemisphere. Since UVB radiation produces 6-4PPs and UVA radiation converts them into DewarPPs through photoisomerization, it is expected that there may be differences in the photoisomerization of 6-4PPs between summer and winter, although that has never been documented. To determine that, isolated DNA was exposed to natural sunlight for 8 h in late summer and in winter, and absolute levels of the three classes of photolesions were quantified using calibrated ELISAs. It was found that sunlight produces CPDs and 6-4PPs in DNA at a ratio of about 9:1 and converts approximately 80% of 6-4PPs into DewarPPs within 3 h. Moreover, photoisomerization is more efficient in winter than in late summer after sunlight irradiation for the same duration, at similar solar UV doses and with the same induction level of CPDs. These results demonstrate that seasonal differences in the UVA/UVB ratio influence the efficiency of the photoisomerization of 6-4PPs into DewarPPs.

[Clinical Outcomes of Endoscope-Assisted 30-Gauge Single-Needle Technique for Intrascleral Intraocular Lens Fixation].

INTRODUCTION: We have developed an endoscope-assisted single-needle technique, which is an improvement of Yamane's double-needle technique of the intrascleral intraocular lens (IOL) fixation techniques. In this surgical procedure, the IOL is manipulated in the vitreous cavity, and the IOL haptic is externalized from the eye one by one with the aid of an ophthalmic endoscope. The purpose of this study was to report the postoperative visual function and safety of this new technique. METHODS: Overall, 19 consecutive eyes (16 patients; mean age, 75.1 ± 9.6 years; mean follow-up period, 5.7 months) that underwent intrascleral IOL fixation surgery with our new technique were included in the study. Manifest refraction, uncorrected/corrected visual acuity, and corneal endothelial cell density were measured before and after surgery. Tilt and decentration of IOL were analyzed using anterior segment optical coherence tomography. RESULTS: The mean absolute prediction error (spherical equivalent) was 0.82 ± 0.52. The mean postoperative best-corrected visual acuity had significantly improved at the final visits (p = 0.02). No significant differences in the mean corneal endothelial cell density were observed between the first (2,232 ± 751 cells/mm2) and final (2,099 ± 649 cells/mm2) visits (p = 0.35). The mean IOL tilt was 8.1 ± 3.2°. There were no vision-threatening complications, such as retinal detachment, endophthalmitis, or IOL dislocation, during or after surgery. CONCLUSIONS: The endoscope-assisted single-needle technique is a safe and effective method of intrascleral IOL fixation surgery.

White-rot fungus Phanerochaete chrysosporium metabolizes chloropyridinyl-type neonicotinoid insecticides by an N-dealkylation reaction catalyzed by two cytochrome P450s.

We previously identified a cytochrome P450 (CYP) derived from the white-rot fungus Phanerochaete chrysosporium as involved in degradation of acetamiprid, a neonicotinoid (NEO) insecticide. In the present study, we investigated biodegradation of other NEOs by P. chrysosporium, and attempted to identify the CYP enzyme responsible for NEO degradation. P. chrysosporium was able to degrade some NEOs (acetamiprid, clothianidin, imidacloprid, and thiacloprid) in nutrient-rich medium. Two CYPs in P. chrysosporium (PcCYPs), CYP5037B3 and CYP5147A3, were identified as major isozymes involved in metabolism of three neonicotinoids that have in common a chloropyridinyl moiety (acetamiprid, imidacloprid, and thiacloprid) by screening yeast that heterologously express PcCYPs. Both PcCYPs catalyzed cleavage of the chloropyridinyl moiety and side chain of the three NEOs by N-dealkylation, resulting in 6-chloro-3-pyridinemethanol and respective side chain fragments. In a culture of P. chrysosporium, 97 % and 74 % of imidacloprid and thiacloprid were modified to form degradation products, and one of these, 6-chloro-3-pyridinemethanol, was further degraded. These two PcCYPs catalyzed almost the same reaction but their substrate specificity and expression pattern are slightly different. Altogether, we found that P. chrysosporium degrades NEOs via the activity of at least two different CYP isozymes.

Clinical characteristics of participants enrolled in an early identification and healthcare management program for dementia based on cluster analysis and the effectiveness of associated support efforts.

OBJECTIVE: Although early identification and management services for dementia have become more widespread, their efficacy and the clinical characteristics of service have yet to be fully evaluated. Therefore, the objective of this study is to clarify these issues. MEASUREMENTS: The subjects were 164 Japanese users of an early identification and management program for dementia, known as the Initial-phase Intensive Support Team (IPIST), between 2013 and 2015. Nonhierarchical cluster analysis was used to derive subgroups based on cognitive status and ability in activities of daily living (ADL) and behavioral and psychological symptoms of dementia (BPSD). One-way analysis of variance was performed to evaluate differences among the groups derived by the cluster analysis. A paired t test was used to assess how the clinical status of the groups changed between baseline and follow-up. RESULTS: Four groups were identified by cluster analysis, i.e. a mild group, a moderate group, a BPSD group with moderate cognitive impairment and severe BPSD, and a severe group with severe cognitive impairment and severe BPSD. Although there were no significant improvements in cognitive impairment or ADL in any group, significant improvements were found in BPSD in the BPSD and severe BPSD groups. Caregiver burden was significantly lessened in all groups. Clinical diagnosis and long-term care insurance service utilization rates were significantly improved overall. CONCLUSION: The users of IPIST were classified into four subgroups based on their clinical characteristics. The IPIST program could improve the quality of life of people with dementia and their caregivers.