We have reported the possibility of an outbreak of a plasmid-borne carbapenemase-producing Enterobacteriaceae at Showa University Hospital using conjugal transfer experiments; however, we could not perform plasmid profiling and fingerprinting to identify the plasmid responsible for the outbreak in clinical isolates. Therefore, to distinguish whether the appearance of metallo-β-lactamase IMP-11 （^blaIMP-11）-producing Enterobacter cloacae （E. cloacae） was due to the same plasmid, we established a plasmid testing system involving plasmid isolation, typing, profiling, and fingerprinting, as well as DNA sequencing analysis of genes surrounding the carbapenemase-encoding gene. Plasmid fingerprinting is an essential tool for identifying plasmids when next-generation sequencing methods cannot be employed. Of note, an important step in fingerprinting is plasmid isolation, which is difficult when large plasmids are involved. In addition, plasmid profiling using S1 nuclease pulse-field gel electrophoresis （PFGE） Southern blotting is an important tool for profiling the size and number of plasmids in bacteria. In this study, we successfully isolated an approximately 90-kb IncL/M plasmid by employing our plasmid analysis system. Importantly, as different ^blaIMP-11-producing E. cloacae isolates carried the same type of plasmid, with similar size and fingerprinting pattern, we suggest that the isolated IncL/M plasmid is the one present in this strain.

抄録全体を表示

Predicting normal values of cardiovascular structure size are essential in managing congenital and pediatric heart diseases. Conventionally, normal values of cardiovascular structure size are predicted based on body surface area （BSA）, which is calculated from the infant’s weight and height. However, the predicted normal values may be more accurate if the actual body composition measurement is considered because there are large individual differences in lean body mass （LBM） and fat mass （FM）. The objective of this study was to evaluate the efficacy of measuring body fat percentage using the PEA POD Infant Body Composition System, a novel pediatric body composition measurement tool, in assessing cardiovascular structures focused on the diameters of the aortic valve （AVD） and mitral valve （MVD） and the left ventricular mass （LVM） in infants. We evaluated the associations between diameters of the AVD and MVD, LVM, and percent body fat （％BF） using the PEA POD system at term-equivalent age （37-42 weeks）. AVD and MVD were not significantly different between groups with high or low ％BF, whereas the differences between the predicted normal values and AVD and between the predicted normal values and MVD were significantly larger in the high ％BF group than those in the low ％BF group （p＜0.05 and p＜0.01, respectively）. The high ％BF group had significantly larger LVM/height^2.16 than the low ％BF group （p＜0.05）, whereas no significant difference in LVM/BSA was found between the two groups. Body composition analysis is crucial for evaluating cardiovascular structure in infants because the existing methods for predicting normal values for valve diameter and LVM are significantly influenced by ％BF.

抄録全体を表示

Fluoride treatment has been well known to improve acid resistance of tooth enamel, leading to the widespread use of fluoride therapies in dentistry such as fluoride rinse and fluoride-releasing dental materials. The effect of fluoridation is likely based on the chemical properties of fluoridized hydroxyapatite; however, nanoscale tiny hydroxyapatite crystals in tooth enamel make it difficult to observe the demineralization pattern of fluoridated enamel versus the untreated enamel at a single crystal level. The purpose of this study was to mimic the demineralization patterns of fluoridated and untreated enamel by means of the newly developed hydrothermally enlarged enamel-like hydroxyapatite single crystals at Showa University. Large-scale hydroxyapatite single crystals were hydrothermally produced from polyphosphoric acid and calcium oxide. The crystals were stored in sodium fluoride solutions with four different concentrations for 30days, then exposed to 3％ citric acid solution for up to 60min. The degradation patterns of each sample were observed using a conventional scanning electron microscope and were analyzed using F K-edge X-ray absorption near edge structure spectra. The surfaces of the hydroxyapatite crystals treated by relatively low concentrations of fluoride showed degradation in citric acid as well as in the untreated control. The hydroxyapatite crystals treated with 1,500 and 9,000ppm F revealed that the fluoridated outer pillar of the crystals remained mostly intact which made calcium fluoride detectable. Fluoridization of tooth enamel might be preventive of an early acid erosion at a crystal level with a caution of sufficient fluoride concentration and exposure over time. The remaining substantial portion of the crystal pillar implies of highly fluoridized crystals, and a possible remineralization occurs as long as saliva provides minerals required for enamel remineralization by in vivo regulation.

抄録全体を表示

Triple negative breast cancer has a high frequency of BRCA1 gene mutations. In this experiment, we examined whether there are cells that are not led to apoptosis in different subtypes of breast cancer with poor prognosis with BRCA1 mutation and wild type BRCA cells. Cells with BRCA1 wild-type （MDA-MB-231 and BT-549） or mutated （MDA-MB-436）BRCA1 were exposed to anticancer drugs, and the levels of reactive oxygen species （ROS）produced by oxidative stress and Annexin V （an index of apoptosis） were examined. The wild-type MDA-MB-231 cells showed increased ROS levels and Annexin V after exposure to eribulin and paclitaxel. Hence, the pathway leading to apoptosis may be activated by oxidative stress. ROS levels in BT-549 cells were significantly increased after exposure to eribulin and paclitaxel. However, there was no change in Annexin V. BRCA1-mutated MDA-MB-436 cells showed significantly increased ROS levels after exposure to eribulin and paclitaxel and no change in the Annexin V levels. This suggests that BRCA1 wild-type BT-549 cells and BRCA1-muted MDA-MB-436 cells were resistant to ROS-mediated apoptosis. These results indicate that BRCA1 mutation and cell subtypes should be investigated prior to selecting the chemotherapy combination to enable appropriate selection in clinical practice.

抄録全体を表示

The cytokine interleukin-34 （IL-34） was recently described. However, its role in the lungs is not well understood. IL-34 binds to the colony stimulating factor-1 receptor, thereby enhancing tissue macrophage maturation and differentiation. Macrophages are essential to the airway inflammation process and acute lung injury （ALI）. This study aimed to evaluate the role of IL-34 in ALI establishment. C57BL/6 male mice were stimulated intratracheally with lipopolysaccharide （LPS） and sacrificed on day 1, 3, 5, or 7. Additionally, the mice were treated with an anti-IL-34 antibody intranasally before LPS stimulation. The bronchoalveolar lavage fluid （BALF） and lung tissues were collected. The cells of the human peripheral blood monocyte cell line THP-1 and the human airway epithelial cell line BEAS-2B were cultured with LPS in vitro. The total cell number in BALF was higher in the LPS-stimulated mice than in the control mice. The BALF IL-34 level was significantly elevated in BALF on days 1 and 3. IL-34 expression was detected in the pulmonary epithelium in the LPS-stimulated mice on day 1. Anti-IL-34 antibody suppressed the number of macrophages in BALF. IL-34 blockade resulted in pulmonary fibrosis reduction in LPS-stimulated mice on day 5. LPS stimulation in vitro induced the production of tumor necrosis factor-α （TNF-α） in THP-1 cells. Furthermore, TNF-α stimulation induced the IL-34 production in BEAS-2B cells. These results suggest that IL-34 induction in the epithelial cells may enhance pulmonary inflammation and fibrosis in the murine model of LPS-induced acute lung injury.

抄録全体を表示

Surgical resection for colorectal cancer（CRC）that deeply invades the submucosa（≥1,000µm）（T1b）has been recommended to reduce the potential risk of lymph node metastasis. In clinical settings, cases of pathological T1b exist, and these cases are treated with endoscopic resection（ER）for various reasons. However, factors that influence the choice of ER to treat T1b CRC remain unknown. Therefore, in this study, we investigated the factors associated with the choice of endoscopic treatments in patients diagnosed with pathological T1b or a more deeply invading CRC. To achieve this aim, we conducted a case series investigation of the previously conducted endoscopic diagnoses, after which we selected treatments for colorectal lesions. The case series comprised 83 lesions endoscopically diagnosed as early CRC, which was subsequently reviewed by eight endoscopists with various levels of experience in magnifying colonoscopy at Showa University Hospital. Then, pathological T1b or T2 lesions were extracted from the case series. We also assessed factors related to ER selection for these lesions using multiple logistic regression and analyzed their contributions using decision tree analysis. Eighteen cases with pathological T1b or more deeply invading lesions were extracted, and the analyses were conducted using 144 data obtained from these 18 lesions as interpreted by the eight reviewers. With multivariate logistic regression, a low estimation level for T1b and high confidence to perform ER were identified as independent factors affecting the selection of ER for T1b. The decision tree analysis further indicated that confidence levels to perform ER influenced treatment selection, especially in lesions diagnosed as probable T1b. Our study therefore demonstrated that factors affecting the selection of ER to treat T1b CRCs were low estimations during endoscopic diagnosis and high confidence to conduct the ER procedure.

抄録全体を表示

Most Rathke’s cleft cysts （RCCs） are asymptomatic. Of the symptomatic RCCs, those that rapidly develop and cause hemorrhagic RCC apoplexy are particularly rare. In this study, we report a case of nonhemorrhagic RCC apoplexy that is an acute-onset RCC without intracystic hemorrhage. This study included a 21-year-old male patient. His chief complaints were severe headache with sudden disturbance of consciousness, visual disturbance, and double vision. Head computed tomography （CT）/magnetic resonance imaging （MRI） and clinical course indicated a hemorrhagic RCC apoplexy that is an acute-onset RCC with intracystic hemorrhage, a nonhemorrhagic RCC apoplexy, or a pituitary apoplexy. We then performed endoscopic transsphenoidal surgery. Histopathological examinations revealed a nonhemorrhagic RCC apoplexy. The preoperative diagnosis makes it difficult to distinguish between acute-onset hemorrhagic RCC apoplexy, nonhemorrhagic RCC apoplexy, and pituitary apoplexy. We compared 26 cases of hemorrhagic RCC apoplexy with cases of nonhemorrhagic RCC apoplexy by reviewing previous literatures. Furthermore, we have determined the characteristics of nonhemorrhagic RCC apoplexy. Knowledge on these characteristics may be useful in the differential diagnosis. For the differential diagnosis and treatment of RCC apoplexy and pituitary apoplexy, it is important to appropriately perform surgical treatment and make an accurate diagnosis based on surgical and pathological findings.

抄録全体を表示

Myelopathy with atlantoaxial instability is a relatively rare condition. It is treated with various surgical methods to treat upper cervical problems, including atlantoaxial fusion, occipitocervical fusion, and C1 laminectomy. However, the choice of surgical method, especially in highly aged （≥80 years） patients, is controversial. This case report describes the difficulty of selecting the appropriate surgical procedure for upper cervical and occipitocervical diseases in highly aged patients. An 85-year-old woman complained of neck pain and bilateral hand numbness. The Japanese Orthopedic Association score for cervical myelopathy （C-JOA） of the patient was 9 out of a possible score of 17. Plain radiographs showed atlantoaxial subluxation （AAS） and vertical subluxation （VS）, whereas magnetic resonance imaging showed spinal cord compression and myelomalacia at C1-2. The patient underwent a C1 laminectomy to minimize invasive procedures. After surgery, her symptoms improved, and her C-JOA score increased to 12. Fifteen months after surgery, her neurological conditions gradually deteriorated again. Her VS progressed postoperatively, with spinal canal restenosis at the craniovertebral junction. After an additional occipitocervical fusion, her symptoms improved, and she had no evidence of recurrence at her final follow-up. Although surgeons tend to choose less-invasive procedures when treating highly aged patients, appropriate surgical procedures may be required （even if invasive for the patient） when less-invasive treatments failed. Hence, it is important to avoid over-selecting less-invasive surgical procedures for highly aged patients.

抄録全体を表示

We performed aneurysm repair with double closure technique of sinus of Valsalva aneurysm（SVA）in a 59-year-old man who was revealed obstructing right ventricular outflow tract（RVOT）with moderate Aortic insufficiency（AI）by transthoracic echocardiography（TTE）. SVA plication was performed resection and suture trans tricuspid valve. Patch closure was performed with double-layer 30mm×30mm bovine pericardial patch. Aortic valve cusps had no abnormalities such as prolapse and AI disappeared after aneurysm repair because the etiology of AI was enlargement of aortic valve annulus. He was discharged with good condition. Computed tomography confirmed disappearance of blood flow in SVA, and TTE showed released RVOT obstruction in follow-up. Double closure technique, which combines resection and suture and patch closure, is useful for treatment of SVA.

抄録全体を表示