Energy landscape analysis and time-series clustering analysis of patient state multistability related to rheumatoid arthritis drug treatment: The KURAMA cohort study.

Rheumatoid arthritis causes joint inflammation due to immune abnormalities, resulting in joint pain and swelling. In recent years, there have been considerable advancements in the treatment of this disease. However, only approximately 60% of patients achieve remission. Patients with multifactorial diseases shift between states from day to day. Patients may remain in a good or poor state with few or no transitions, or they may switch between states frequently. The visualization of time-dependent state transitions, based on the evaluation axis of stable/unstable states, may provide useful information for achieving rheumatoid arthritis treatment goals. Energy landscape analysis can be used to quantitatively determine the stability/instability of each state in terms of energy. Time-series clustering is another method used to classify transitions into different groups to identify potential patterns within a time-series dataset. The objective of this study was to utilize energy landscape analysis and time-series clustering to evaluate multidimensional time-series data in terms of multistability. We profiled each patient's state transitions during treatment using energy landscape analysis and time-series clustering. Energy landscape analysis divided state transitions into two patterns: "good stability leading to remission" and "poor stability leading to treatment dead-end." The number of patients whose disease status improved increased markedly until approximately 6 months after treatment initiation and then plateaued after 1 year. Time-series clustering grouped patients into three clusters: "toward good stability," "toward poor stability," and "unstable." Patients in the "unstable" cluster are considered to have clinical courses that are difficult to predict; therefore, these patients should be treated with more care. Early disease detection and treatment initiation are important. The evaluation of state multistability enables us to understand a patient's current state in the context of overall state transitions related to rheumatoid arthritis drug treatment and to predict future state transitions.

Successful Antimicrobial Therapy of Esophageal Stenosis Because of Actinomycosis.

Esophageal stenosis can cause vomiting or dysphagia in children and is commonly treated with esophageal balloon dilation. However, surgery may be required if the stenosis does not respond to dilation. Although esophageal actinomycosis can cause severe esophageal strictures and be refractory to balloon dilation, it has been reported to respond effectively to antimicrobial therapy in adults. However, the course of the disease and appropriate treatment strategies in children are not well understood. We present a case of a previously healthy 2-year-old boy diagnosed with esophageal stenosis because of actinomycosis. The patient was treated with intravenous penicillin G, followed by oral amoxicillin for 8 weeks and 6 months, respectively. After completion of the antimicrobial treatment, the patient showed improvement in symptoms and endoscopic findings. At the 1-year follow-up, the patient showed consistent weight gain and normal growth without further intervention. This case highlights the importance of considering esophageal actinomycosis as a potential cause of esophageal stenosis in children and the potential effectiveness of antimicrobial therapy in avoiding surgical intervention.

Optimal Surgical Method and Timing for Low-birth-weight Esophageal Atresia Babies: Multi-institutional Observational Study.

AIM OF THE STUDY: Previous research has shown that low birth weight is one of the risk factors for esophageal atresia. However, there remains a paucity of evidence on the timing and the treatment method. METHOD: Data were collected using a multi-institutional observational study in 11 hospitals that performed surgeries on esophageal atresia babies whose birth weights were ≤1500 g from 2001 to 2020. RESULTS: Of the 46 patients analyzed, median birth weight was 1233 (IQR 1042-1412) g. Within 46 cases, 19 (41%) underwent definitive esophageal anastomosis at the median of age in 8 (IQR 2-101) days. Thirteen out of 19 experienced either closure of tracheoesophageal fistula, gastrostomy, or esophageal banding at the first operation, followed by esophageal anastomosis. Seven infants, including four cases of <1000 g, underwent anastomosis after one month of age to wait for weight gain (variously 2-3000 g). Twenty-one out of 27 infants (78%) who did not receive anastomosis died within one year of age, including 21 (78 %) with major cardiac anomalies and 24 (89%) with severe chromosomal anomalies (trisomy 18). Six survivors in this group, all with trisomy 18, lived with palliative surgical treatments. CONCLUSION: In our study, the definitive esophageal anastomosis was effective either at the first operation or as a later treatment after gaining weight. Although having severe anomalies, some infants receive palliative surgical treatments, and the next surgery was considered depending on their condition. EVIDENCE LEVEL: II.

Dementia Scale Classification with Sequential Model from Sleep Activity Data.

Dementia, a disorder caused by brain diseases, has been found to influence the sleep patterns of patients. The finding indicates that monitoring sleep activity is helpful to detect the change in cognitive status. With this in mind, the aim of this study is to explore the possibility to develop a machine learning model for classifying the scores of dementia screening tests based on sleep activity data which could be recorded with less burden for participants. In this study, We collected sleep activity data from 124 elderly patients with varying cognitive states, including heart rate, respiratory rate and depth of sleep, using a single sensor. The score of Mini Mental State Estimation (MMSE) cognitive test is used to determine the level of cognitive states. First, we conducted a statistical analysis of the measured sleep activity data to find specific features observed in people with low-MMSE scores. Second, we utilized an efficient sequence model for capturing time-series changes in sleep activity for binary classification of the dementia scale to detect such low-MMSE people. Our findings revealed significant distinctions in sleep patterns between high and low cognitive status groups, and in the classification task, a maximum macro F1 score of 0.67 was achieved using LSTM models. Our results suggest the validity of using sleep activity data for the prediction of dementia classification.

How many cases do instructor class pediatric surgeons need to experience to be an independent operator in performing advanced endoscopic surgery? A nationwide survey to establish an ideal curriculum for pediatric endoscopic surgery in Japan.

PURPOSE: To ensure the safe spread of pediatric endoscopic surgery, it is essential to build a training curriculum, and a survey of the current situation in Japan is necessary. The present study assessed an efficient training curriculum by clarifying instructor class pediatric surgeons' experiences, including autonomy when performing advanced endoscopic surgeries. METHODS: An online nationwide questionnaire survey was conducted among pediatric surgeons who had Endoscopic Surgical Skill Qualification (ESSQ) and board-certified instructors who had skills comparable to ESSQ. We assessed participants' training experience, opinions concerning the ideal training curriculum, and the correlation between surgical experience and the level of autonomy. The Zwisch scale was used to assess autonomy. RESULTS: Fifty-two participants responded to the survey (response rate: 86.7%). Only 57.7% of the respondents felt that they had received sufficient endoscopic surgery training. Most respondents considered an educational curriculum for endoscopic surgery including off-the-job training essential during the training period. Autonomy had been acquired after experiencing two to three cases for most advanced endoscopic surgeries. CONCLUSION: This first nationwide survey in Japan showed that instructor class pediatric surgeons acquired autonomy after experiencing two to three for most advanced endoscopic surgeries. Our findings suggest that training, especially off-the-job training, has been insufficient.

Comprehension of fundamental knowledge about pediatric endoscopic surgery: a cross-sectional study in Japan.

BACKGROUND: Pediatric endoscopic surgery has become an alternative to conventional techniques with the development of medical equipment. However, there is no formal, standardized curriculum for pediatric endoscopic surgery, and its requirement remains elusive. The purpose of this study is to determine the baseline knowledge of pediatric surgeons that is considered essential for pediatric laparoscopic and thoracoscopic surgery. METHODS: Sixteen web-based multiple-choice questions based on the fundamental cognitive knowledge of pediatric endoscopic surgery were administered. The questions were created based on the fields covered by the Fundamentals of Laparoscopic Surgery ™ (FLS) certification examination blueprints and eight specific diseases of pediatric surgery. Pediatric surgeons and pediatric surgical trainees participated in this study voluntarily. RESULTS: A total of 122 surgeons participated through the Japanese Society of Pediatric Surgeons. The response rate was 95% (122/128). The total mean examination score of all participants was 79.4% (77.3-81.4%). There were no significant differences in total scores between the board-certified pediatric surgeons without an endoscopic surgical skill qualification and the non-board-certified pediatric surgeons (80.4% vs. 77.1%, p = 0.12). The endoscopic surgical skill-qualified surgeons had significantly higher percentages of correct responses in specific subjects than board-certified pediatric surgeons and surgeons without pediatric board certification (94.3% vs. 82.9%, p = 0.02; 94.3% vs. 77.5%, p = 0.0002). The FLS original subjects' scores were not significantly different among them. The mean score of surgeons who had experienced more than 200 cases of endoscopic surgery, including adult cases, was 83.2% (80.4-85.9%). CONCLUSIONS: A knowledge gap exists between surgeons, board-certified pediatric surgeons, and endoscopic surgical skill-qualified surgeons in Japan. In the field of pediatric surgery, an effective formal curriculum, such as FLS, is required to help address this vast knowledge gap for the safe conduct of endoscopic surgeries.

In Vitro Production of Optically Active Octahydrocurcumin by Human Intestinal Bacterium.

Enterococcus avium, producing 5R-hexahydrocurcumin metabolized tetrahydrocurcumin to octahydrocurcumin in vitro. Based on a detailed analysis of the two secondary alcohols, the metabolite obtained from tetrahydrocurcumin via 5R-hexahydrocurcumin was identified as 3R,5R-octahydrocurcumin. The activities of 5R-hexahydrocurcumin and 3R,5R-octahydrocurcumin were compared to those of the synthetic compounds, using monocyte chemoattractant protein-1 produced via murine adipocytes in vitro. The optically active curcuminoids reduced the cytokine production similar to tetrahydrocurcumin without any difference in their stereochemistry.

Perioperative outcomes of laparoscopic fundoplication for gastroesophageal reflux disease in children with or without scoliosis.

PURPOSE: This study aimed to evaluate the perioperative outcomes of laparoscopic fundoplication (LF) for gastroesophageal reflux disease (GERD) in children with scoliosis. METHODS: Data of consecutive patients with GERD who underwent LF from January 2015 to December 2020 at a single pediatric institution were retrospectively analyzed. RESULTS: Eighty-two patients underwent laparoscopic Nissen fundoplication. The median [interquartile range (IQR)] body weight was 9.3 [7; 14] kg. Seventy-five patients were neurologically impaired (91%), and other comorbidities included scoliosis (n = 33), lung disease (n = 39), and cardiac disease (n = 14). The median (IQR) operative time including the creation of the gastrostomy and volume of bleeding were 160 [143; 190] min and 2 [1; 5] mL, respectively. There were no significant differences between patients with and those without scoliosis (p = 0.17 and p = 0.90, respectively). Patients with cardiac disease had a longer operative time (167 [161; 193] vs. 157 [141; 190] min, p = 0.01). There were three post-operative complications in children with neurological impairment; however, there was no clear relationship between the severity of scoliosis and complications. CONCLUSION: Severity of scoliosis did not correlate with perioperative results and post-operative complications. This suggests that the same LF technique can be used regardless of the presence or absence of scoliosis in children.

Effects of isoflavone-rich red clover extract on blood glucose level: A randomized, double-blind, placebo-controlled trial.

High blood glucose is associated with increased risk of various diseases. Red clover (RC; Trifolium pratense L.) is an edible legume whose sprout is rich in isoflavones such as formononetin and biochanin A. We examined the effects of RC extract on postprandial and fasting blood glucose level, using a randomized, double-blind, placebo-controlled trial with 36 participants, aged 25 to 64 years, who were randomly assigned to receive either 1.91 g of RC extract (containing 8 mg formononetin and 1.8 mg biochanin A) or placebo. Each participant ingested the assigned test food daily for 8 weeks, and at the oral maltose tolerance test (OMTT). Initially, the two groups did not significantly differ in OMTT results. However, fasting insulin levels at 8 weeks were significantly lower in the RC group (4.76 µIU/ml at Week 0 to 4.01 µIU/ml at Week 8) with a significant interaction (P = 0.046). Subgroup analysis showed that change in blood glucose level (blood glucose ΔC) tended to decrease late in the trial period during OMTT in the ≤50-year-old RC group, as did fasting blood glucose and insulin levels at 8 weeks; hemoglobin A1c was also significantly reduced in this subgroup (5.36% at Week 0 to 5.28% at Week 8) with a significant interaction (P = 0.040). These results suggest that the daily intake of RC could reduce blood glucose, particularly for those ≤50 years old. Formononetin-an α-glucosidase inhibitor-is considered to be the major functional molecule for these effects. Therefore, intake of RC that contains formononetin might help blood glucose control.

Production of Optically Active Hexahydrocurcumin by Human Intestinal Bacterium in Vitro.

A hexahydrocurcumin-producing bacterium named 2a1-2b was isolated from human feces. It was observed that the bacterium had more than 99% similarity with Enterococcus avium ATCC14025T according to 16S ribosomal DNA (rDNA) sequence. The strain 2a1-2b produced optically active 5R-hexahydrocurcumin (enantiomeric excess (e.e.) > 95%) from tetrahydrocurcumin but not from curcumin. Our results showed that intestine is an important place for producing hexahydrocurcumin.

Benzyl Isothiocyanate Produced by Garden Cress (Lepidium sativum) Prevents Accumulation of Hepatic Lipids.

We determined the physiological effects of glucotropaeolin-rich lyophilized garden cress sprout powder (GC) administered to fasting and nonfasting mice. High-performance liquid chromatography analysis revealed glucotropaeolin (57.4±1.1 mg/g dry weight) as a major phytochemical constituent of GC. Decreasing tendency in body weight and feeding efficiency ratio were detected in the group of mice fed 0.05% (w/w) GC (GC0.05). Nonfasting mice exhibited significantly lower liver weights that were unchanged after fasting. Decreased total lipid (TL) and triglyceride (TG) levels in the liver were detected in the nonfasted GC0.01 and GC0.05 groups, but only in TLs of the fasted groups. The levels of plasma TGs and nonesterified fatty acids of the GC0.05 group, which remained unchanged during nonfasting, decreased after fasting. To determine its effects on the accumulation of lipids in the liver, the glucotropaeolin aglycone, benzyl isothiocyanate (BITC), was added to the liver-derived HepG2 human cell line cultured in a medium containing a high concentration of D-glucose (4,500 mg/L D-glucose) (HG group) or 1 mM oleic acid (SO group). Toxicity was not detected when cells were treated with as much as 5 µM BITC; however, lipid accumulation was inhibited by BITC in a concentration-dependent manner in the HG groups. The same effect was observed when 2 µM BITC was added to the diet of the SO groups. These results suggest that moderate levels of GC or BITC are useful for reducing liver and plasma TGs.

Red Clover (Trifolium pratense L.) Sprout Prevents Metabolic Syndrome.

We examined the prevention effect of red clover (Trifolium pratense L.) sprout on metabolic syndrome using a high-carbohydrate and high-fat diet (Western diet; WD)-induced male C57BL/6J obese model mouse. Red clover sprout-lyophilized powder (RC) contained 3.5 mg/g dry-weight of formononetin as a major phenolic compound, as analyzed by high performance liquid chromatography. Supplementation of 0.3% (w/w) RC in a WD (WD+RC) showed an anti-obesity effect and ameliorated lipid metabolism in the obese model mice. Additionally, fasting plasma glucose levels were significantly reduced in the WD+RC group. Administration of 0.1 mg/kg formononetin reduced the postprandial blood glucose level, as assessed using the oral maltose tolerance test. However, no significant formononetin intake effect was observed on the plasma insulin level. These results suggest that the formononetin contained in red clover sprout inhibits α-glucosidase and thereby contributes to reducing the postprandial blood glucose response in mice.

Equol Inhibits Mushroom Tyrosinase in Vitro through Tight Binding.

Equol, an intestinal metabolite of daidzein, inhibited more potently mushroom tyrosinase in vitro than other inhibitors, genistein and kojic acid. We investigated the mechanism underlying tyrosinase inhibition by equol. Treating racemic equol with tyrosinase produced 3'-hydroxyequol. Because the optical activity of the product showed <25% enantiomeric excess, the reaction was not highly stereospecific. Using enzyme-linked immunosorbent assays with an anti-equol monoclonal antibody, we observed that equol bound to pre-coated tyrosinase in a dose-dependent manner. Our results suggested the formation of a stable equol-tyrosinase complex.

Evaluation methods and impact of simulation-based training in pediatric surgery: a systematic review.

PURPOSE: The aim of this study was to identify (1) the type of skill evaluation methods and (2) how the effect of training was evaluated in simulation-based training (SBT) in pediatric surgery. METHODS: Databases of PubMed, Cochrane Library, and Web of Science were searched for articles published from January 2000 to January 2017. Search concepts of Medical Subject Heading terms were "surgery," "pediatrics," "simulation," and "training, evaluation." RESULTS: Of 5858 publications identified, 43 were included. Twenty papers described simulators as assessment tools used to evaluate technical skills. Reviewers differentiated between experts and trainees using a scoring system (45%) and/or a checklist (25%). Simulators as training tools were described in 23 papers. While the training's effectiveness was measured using performance assessment scales (52%) and/or surveys (43%), no study investigated the improvement of the clinical outcomes after SBT. CONCLUSION: Scoring, time, and motion analysis methods were used for the evaluation of basic techniques of laparoscopic skills. Only a few SBT in pediatric surgery have definite goals with clinical effect. Future research needs to demonstrate the educational effect of simulators as assessment or training tools on SBT in pediatric surgery.

Identifying the needs for teaching fundamental knowledge of laparoscopic surgery: a cross-sectional study in Japan.

BACKGROUND: Recently, laparoscopic surgery (LS) has become a more common procedure than traditional open surgery. Although LS-related adverse events have been reported, there is no formal, standardized curriculum to teach the fundamentals of LS in Japan. Understanding surgeons' knowledge regarding LS is crucial for developing an educational curriculum. The purpose of this study was to determine the baseline knowledge on LS of surgeons and surgical trainees in Japan. METHODS: Participants completed 24 multiple-choice questions testing basic cognitive knowledge of LS and a questionnaire regarding the status of laparoscopic education. The examination was developed according to the 13 content domains of the Fundamentals of Laparoscopic Surgery (FLS) program. Scores were compared between post-graduate year (PGY) > 5 and PGY 1-5 participants. Data are expressed as median scores and interquartile ranges. Wilcoxon signed-rank test was used for statistical analysis. RESULTS: A total of 195 surgeons and surgical trainees from 10 teaching hospitals (PGY1-5: 66, PGY > 5: 129) across Japan completed the examination. The median score in the entire cohort was 75 [67; 83] %, with significantly higher scores in the PGY > 5 group compared to the PGY1-5 group (79 [75; 83] % vs. 67 [58; 75] %, p < 0.001). The differences in performance were due to better scores for PGY > 5 group on the sections "equipment," "patient considerations," "abdominal access," "tissue handling," "hemorrhage and hemostasis," "tissue approximation," and "exiting the abdomen." Overall, the median scores in the "energy sources" and "establishment and physiology of the pneumoperitoneum" subsections were lower than in other domains. All participants agreed on the need for fundamental knowledge and a formal educational curriculum. CONCLUSIONS: Compared to experienced surgeons, surgical trainees had lesser knowledge about performing LS. Regardless of the years of experience, there are crucial knowledge gaps in specific areas regarding safe LS that should be addressed by implementing an educational curriculum.

Daidzein reductase of Eggerthella sp. YY7918, its octameric subunit structure containing FMN/FAD/4Fe-4S, and its enantioselective production of R-dihydroisoflavones.

S-Equol is a metabolite of daidzein, a type of soy isoflavone, and three reductases are involved in the conversion of daidzein by specific intestinal bacteria. S-Equol is thought to prevent hormone-dependent diseases. We previously identified the equol producing gene cluster (eqlABC) of Eggerthella sp. YY7918. Daidzein reductase (DZNR), encoded by eqlA, catalyzes the reduction of daidzein to dihydrodaidzein (the first step of equol synthesis), which was confirmed using a recombinant enzyme produced in Escherichia coli. Here, we purified recombinant DZNR to homogeneity and analyzed its enzymological properties. DZNR contained FMN, FAD, and one 4Fe-4S cluster per 70-kDa subunit as enzymatic cofactors. DZNR reduced the CC bond between the C-2 and C-3 positions of daidzein, genistein, glycitein, and formononetin in the presence of NADPH. R-Dihydrodaidzein and R-dihydrogenistein were highly stereo-selectively produced from daidzein and genistein. The Km and kcat for daidzein were 11.9 µM and 6.7 s-1, and these values for genistein were 74.1 µM and 28.3 s-1, respectively. This enzyme showed similar kinetic parameters and wide substrate specificity for isoflavone molecules. Thus, this enzyme appears to be an isoflavone reductase. Gel filtration chromatography and chemical cross-linking analysis of the active form of DZNR suggested that the enzyme consists of an octameric subunit structure. We confirmed this by small-angle X-ray scattering and transmission electron microscopy at a magnification of ×200,000. DZNR formed a globular four-petal cloverleaf structure with a central vertical hole. The maximum particle size was 173 Å.

The production of S-equol from daidzein is associated with a cluster of three genes in Eggerthella sp. YY7918.

Daidzein (DZN) is converted to equol (EQL) by intestinal bacteria. We previously reported that Eggerthella sp. YY7918, which is found in human feces, is an EQL-producing bacterium and analyzed its whole genomic sequence. We found three coding sequences (CDSs) in this bacterium that showed 99% similarity to the EQL-producing enzymes of Lactococcus sp. 20-92. These identified CDSs were designated eqlA, eqlB, and eqlC and thought to encode daidzein reductase (DZNR), dihydrodaidzein reductase (DHDR), and tetrahydrodaidzein reductase (THDR), respectively. These genes were cloned into pColdII. Recombinant plasmids were then introduced into Escherichia coli BL21 (DE3) and DZNR, DHDR, and THDR were expressed and purified by 6×His-Tag chromatography. We confirmed that these three enzymes were involved in the conversion of DZN to EQL. Purified DZNR converted DZN to dihydrodaizein (DHD) in the presence of NADPH. DHDR converted DHD to tetrahydrodaizein (THD) in the presence of NADPH. Neither enzyme showed activities with NADH. THDR converted THD in the absence of cofactors, NAD(P)H, and also produced DHD as a by-product. Thus, we propose that THDR is not a reductase but a new type of dismutase. The GC content of these clusters was 64%, similar to the overall genomic GC content for Eggerthella and Coriobacteriaceae (56-60%), and higher than that for Lactococcus garvieae (39%), even though the gene cluster showed 99% similarity to that in Lactococcus sp. 20-92. Taken together, our results indicate that the gene cluster associated with EQL production evolved in high-GC bacteria including Coriobacteriaceae and was then laterally transferred to Lactococcus sp. 20-92.

Th17 Cell Induction by Adhesion of Microbes to Intestinal Epithelial Cells.

Intestinal Th17 cells are induced and accumulate in response to colonization with a subgroup of intestinal microbes such as segmented filamentous bacteria (SFB) and certain extracellular pathogens. Here, we show that adhesion of microbes to intestinal epithelial cells (ECs) is a critical cue for Th17 induction. Upon monocolonization of germ-free mice or rats with SFB indigenous to mice (M-SFB) or rats (R-SFB), M-SFB and R-SFB showed host-specific adhesion to small intestinal ECs, accompanied by host-specific induction of Th17 cells. Citrobacter rodentium and Escherichia coli O157 triggered similar Th17 responses, whereas adhesion-defective mutants of these microbes failed to do so. Moreover, a mixture of 20 bacterial strains, which were selected and isolated from fecal samples of a patient with ulcerative colitis on the basis of their ability to cause a robust induction of Th17 cells in the mouse colon, also exhibited EC-adhesive characteristics.

Stereochemical determination of O-desmethylangolensin produced from daidzein.

We had isolated an O-desmethylangolensin (O-DMA)-producing bacterium, Clostridium rRNA cluster XIVa strain SY8519. According to chiral separation using HPLC, the SY8519-produced O-DMA exhibited high optical purity. To determine the absolute stereochemistry of O-DMA, we prepared 2-(4-hydroxyphenyl)propionic acid (2-HPPA) from the O-DMA using the Baeyer-Villiger reaction. From chiral analysis of the product, the major peak had the same stereochemistry to that of 2-HPPA produced from genistein by the same bacteria. As we have determined the stereochemistry of SY8519-produced 2-HPPA to have an R configuration, by the chemical synthesis of (S)-2-HPPA, the SY8519-produced O-DMA must also possess R stereochemistry at the 2-position. To study the stereoselective metabolism, we applied racemic dihydrodaidzein to SY8519. The O-DMA was isolated from the culture media and starting material was also recovered. The O-DMA produced was optically active in a similar manner to that produced from daidzein. However, the remaining dihydrodaidzein exhibited no difference between the enantiomers. These results suggested that SY8519 produces (R)-O-DMA from both enantiomers of dihydrodaidzein.

Characterization of Alcaligenes faecalis strain AD15 indicating biocontrol activity against plant pathogens.

Bacterial strain possessing both bacteriostatic and fungistatic activity (biocontrol activity) against pathogens of cyclamen (Cyclamen sp.) was isolated from the soil in Gifu Prefecture, Japan, and characterized with respect to its taxonomic and biocontrol properties. The sequence of its 16S rRNA gene, morphology, biochemistry, and fatty acid composition demonstrated that it is a strain most closely related to Alcaligenes faecalis subsp. faecalis LMG 1229(T). The isolate was named A. faecalis strain AD15. A. faecalis AD15 produced hydroxylamine at maximum yields of 33.3±1.7 mg/L after 16 h cultivation in LB medium and 19.0±0.44 mg/L after 19 h cultivation in synthetic medium. Moreover, minimum inhibitory concentrations of hydroxylamine against the cyclamen pathogens Pantoea agglomerans and Colletotrichum gloeosporioides were 4.20±0.98 and 16.5±0.67 mg/L. These results indicated that the biocontrol activity of strain AD15 might be attributed to hydroxylamine, a metabolite in the culture medium, and it had the potential for biopesticide application.