AmpC is a class C Ambler β-lactamase that confers resistance to cephamycins. Globally reported AmpC-producing Enterobacterales are clinically important due to their therapeutic restrictions and epidemiology. Between April 2021 and May 2021, an outbreak of AmpC beta-lactamase-producing Escherichia coli occurred at Showa University Hospital. Because of this outbreak, plasmid typing, enterobacterial repetitive intergenic consensus-polymerase chain reaction （ERIC-PCR） analysis, conjugation experiments, and pulsed-field gel electrophoresis （PFGE） were performed to study the molecular epidemiological characteristics of these E. coli strains. ERIC-PCR and conjugation experiments detected IncFrepB＋, IncFIA＋, and IncFIB＋ multiple-replicon conjugative plasmids carrying the AmpC gene （bla_DHA-1）. Five of eleven isolates showed the same PFGE banding pattern in the XbaI-digested genomic DNA, whereas the remaining six strains displayed minor variants. These data highlight the need for improvements to infection control and surveillance measures to prevent the spread of bla_DHA-1-carrying E. coli strains.

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Temporary anchorage devices （TADs） have become increasingly popular as orthodontic treatment measures for anchorage or distal movement of molars. However, TAD failure is a major limitation, and the aim of this study was to examine the effects of various factors on the timing of TAD failure. This study included 467 TADs implanted on the buccal side of the molar region in 197 patients undergoing orthodontic treatment. The relationship between failure and sex, age, jaw （maxilla or mandible）, side （left or right）, Frankfort mandibular plane angle （FMA）, point A-nasion-point B angle （ANB）, overbite, and overjet was examined. The time （number of days） until failure was also investigated. The failure rates were significantly higher in men compared to women （23.9％ vs. 13.6％; p-value＝0.024）, and in the mandible compared to the maxilla （28.2％ vs. 11.8％; p-value＜0.001）. A significant difference by age-group was also observed （p-value＜0.029）, with the failure rates being highest among patients aged ≥30 years （29.8％）. Approximately half （47.6％） of the maxillary failures occurred by day 120, and more than half （58.1％） of the mandibular failures occurred by day 60. Moreover, the failure rate by day 120 was higher in the maxilla when the FMA was smaller. The failure rates of TADs implanted on the buccal side of the molar region were influenced by sex, age, and location （i.e., mandible or maxilla）. Failure tended to occur more rapidly and readily in mandibular compared to maxillary implants. Moreover, when considering the vertical skeletal pattern, failure rates ＜120 days after implantation tended to increase when the FMA decreased.

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The assessment of jaw movements is a common method of evaluating stomatognathic function. However, with conventional methods, detailed examination of the interrelationship between maxillofacial morphology, tooth morphology, and jaw movements is difficult. Therefore, we engineered a method of analyzing individual three-dimensional （3D） jaw movements along a time axis. This study included five adult patients with permanent dentition and no notable oral parafunctional habits who visited the orthodontic department of the Showa University Dental Hospital. We used a jaw movement analysis system to assess jaw movements during free mastication. We assessed the （1） movement trajectory of the main occluding area, （2） rate of change in the distance between the origin and the insertion of the masticatory muscles, and （3） contact patterns of the dentition. The results for （1） showed no interrelationships. For （2）, the origin and insertion of the lateral pterygoid muscle exhibited characteristic changes. The analysis of the contact pattern between the upper and lower dentition showed the contact of the molars posterior to the first premolar when masticating on the balancing side. These results indicate that jaw movements occur in a way that is appropriate for the maxillofacial morphology when food is crushed during mastication. Additionally, the occlusal contact and condylar movement during mastication may be more affected on the balancing side than on the working side. Thus, the jaw movement analysis system used in this study was useful for movement analysis during functional activity.

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This single-center, retrospective study was aimed to evaluate the prophylactic efficacy of oral cefcapene pivoxil （CFPN-PI） in preventing perioperative surgical site infections （SSIs）. We obtained hospital records of patients on CFPN-PI prescription between August 25, 2014, and August 25, 2017, at Showa University Hospital in Tokyo, Japan. Patients hospitalized for urological surgery were divided into the CFPN-PI group and non-CFPN-PI group according to administration of antibiotic injection within 72hr of surgery. The incidence of SSI was calculated up to 30 days postoperation in both groups. Of the 1,158 patients, 360 met the inclusion criteria, and 207 received oral cephalosporin and 153 did not. The incidence of SSI was 4.8％ and 3.2％ in the CFPN-PI and the non-CFPN-PI groups, respectively. The incidence of SSI was not significantly different between the two groups （crude odds ratio: 1.5, 95％ confidence interval: 0.50-4.50, p＝0.59）. Perioperative, prophylactic, oral administration of CFPN-PI does not reduce the risk of SSI in patients who have undergone urological surgery.

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Phosphate binders, such as iron （III） citrate hydrate （FCH）, are essential medications for hemodialysis patients. Some in vivo studies have demonstrated that FCH prevented induction of oxidative stress in the presence of transferrin. However, how FCH affects iron-related oxidative stress in the absence of transferrin remains unclear. In the current study, we investigated the effects of ferric citrate （FC） on oxidative stress in the absence of transferrin in vitro to address this question. Human U937 monocytes were pretreated with FC, iron （II） chloride tetrahydrate （FeCl₂・4H₂O）, iron （III） chloride hexahydrate （FeCl3・6H₂O）, or saccharated ferric oxide for 24 h and then treated with 10-mM hydrogen peroxide （H₂O₂） for 30 min. The final Fe concentrations were adjusted to approximately 200µg/dl. Iron concentration, intracellular reactive oxygen species （ROS） levels, and intracellular lipid peroxidation of the cell membrane were measured. After treatment with FC, iron concentration and ROS levels increased. Change in lipid peroxidation after treatment with FC was not observed. However, after treatment with H₂O₂, no change was observed in the intracellular ROS levels in FC-pretreated cells, whereas lipid peroxidation of the cell membrane was decreased. Despite the high iron concentration in FC-pretreated cells, neither intracellular ROS nor cell membrane lipid peroxidation levels were increased with H₂O₂ treatment. Their results might represent antioxidative effects of FC. The results of this study may contribute to a better understanding of the effects of oxidative stress in hemodialysis patients treated with FCH.

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Differential cyanosis indicates a lower percutaneous oxygen saturation （SpO₂） level in the lower extremities than in the upper extremities and is generally observed in patients with interrupted aortic arch （IAA）. We report a case of the absence of differential cyanosis in a neonate with IAA. A male neonate was born at 38weeks of gestation. Despite routine care, his SpO₂ level dropped to 90％ at 1h after birth. On admission, there was no evidence of differential cyanosis. Systolic murmur was noted 12h after birth, leading to suspicion of IAA on echocardiography; IAA type B was confirmed by computed tomography. IAA type B occurs between the left carotid artery and left subclavian artery. In our patient, the levels of SpO₂ were different between the ear and lower extremities without signs of differential cyanosis because his right subclavian artery branched from the aorta distal to the interruption and left subclavian artery. In conclusion, despite the absence of differential cyanosis and lack of detailed echocardiographic evaluation, careful observation is mandatory. SpO₂ measurement in the ear is important to rule out IAA.

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We present a case of a male patient with type 1 diabetes mellitus who developed exogenous insulin antibody syndrome （EIAS）, ameliorated by immunosuppressive treatment including glucocorticoid for concomitant systemic lupus erythematosus （SLE）. A 43-year-old man with fulminant type 1 diabetes mellitus developed severe insulin resistance after approximately 8months of insulin therapy. He required 〜270insulin units/day, and EIAS was diagnosed based on the clinical course and the extremely high-binding rate of the insulin antibody. Two years later, he developed proteinuria, lymphopenia, low complement levels, and positive autoantibodies, and SLE was diagnosed. Glucocorticoid pulse therapy was started, followed by administration of mycophenolate mofetil and hydroxychloroquine. Although hyperglycemia might have been associated with glucocorticoid pulse therapy, the required insulin dose was reduced to 18 units/day. In diabetic patients who develop EIAS, the coexistence of immunological disorders such as SLE should be monitored, and glucocorticoid pulse therapy may be an effective alternative treatment option for EIAS.

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