Publications by authors named "Kazuaki Miyamoto"

136 Publications

A liver metastasis 7 years after resection of a low-risk duodenal gastrointestinal stromal tumor.

Clin J Gastroenterol 2021 Jun 11. Epub 2021 Jun 11.

Department of Surgery, National Hospital Organization, Higashihiroshima Medical Center, 513 Jike, Saijo-cho, Higashihiroshima, Hiroshima, 739-0041, Japan.

Duodenal gastrointestinal stromal tumors (dGISTs) are rare, and a lack of consensus exists regarding their treatment, particularly for recurrent disease. We herein report a rare case of liver metastasis 7 years after resection of a low-risk duodenal gastrointestinal stromal tumor. A 45-year-old woman revealed positive fecal occult blood. Upper gastrointestinal endoscopy revealed a submucosal duodenal tumor with ulceration and oozing on the apex. Endoscopic ultrasound showed a hypoechoic mass originating in the submucosa. Contrast-enhanced abdominal computed tomography (CT) revealed a 30-mm hyper-vascular tumor in the duodenal bulb. The patient underwent partial resection of the duodenal bulb with distal gastrectomy, followed by Roux-en-Y reconstruction. Histopathological evaluation revealed a tumor comprised of spindle-shaped cells including 5 mitotic figures per 50 high-power fields. Immunohistochemical evaluation indicated that the tumor cells were positive for c-Kit and CD34 expression. The tumor was diagnosed as low-risk dGIST. Postoperative follow-up was continued, and 7 years later, CT revealed a 39-mm enhanced tumor in liver segment 4. The tumor was diagnosed as a metastatic liver tumor, and the patient underwent S4 partial hepatectomy. As a result of histological and immunohistochemical analysis, the tumor was diagnosed as a liver metastasis from dGIST. The patient has been receiving oral imatinib 400 mg daily and remains free of disease 5 years after her last surgery. Low-risk dGIST can metastasize relatively long after surgery. However, an excellent long-term prognosis may be achieved by combining complete resection and imatinib therapy in patients with recurrent liver metastases.
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http://dx.doi.org/10.1007/s12328-021-01464-wDOI Listing
June 2021

A Case of Stage II Ascending Colon Cancer with Cardiac Tamponade Due to Pericardial Metastasis.

Am J Case Rep 2021 Jun 7;22:e932239. Epub 2021 Jun 7.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, Hiroshima, Japan.

BACKGROUND Malignant tumors, such as lung and breast cancers, can metastasize to the heart. However, cardiac metastasis rarely occurs in colorectal cancer. Cardiac metastasis cases are typically asymptomatic and rarely cause cardiac tamponade. Heart failure due to systemic metastasis is a terminal symptom; therefore, cardiac metastasis is rarely diagnosed when a patient is alive. We report a case of stage II ascending colon cancer with cardiac tamponade due to pericardial metastasis. CASE REPORT The patient was a 63-year-old woman who underwent laparoscopic ileocecal resection for ascending colon cancer. The final pathological diagnosis was stage IIB cancer. At the time of surgery, computed tomography scans revealed no metastases to the regional lymph nodes, liver, lungs, and other organs. The patient was then referred for dyspnea 5 months after the surgery. Computed tomography revealed large quantities of pericardial effusion, and the patient was diagnosed with cardiac tamponade. The symptoms were alleviated after pericardiocentesis. Cytological examination of the pericardial fluid confirmed the diagnosis of adenocarcinoma, and by extension, cardiac metastasis of the ascending colon cancer. Anticancer agents were recommended, but the patient opted for palliative treatment. CONCLUSIONS We report a rare case of ascending colon cancer with pericardial metastasis. The advancements in chemotherapy have made the prognosis of colorectal cancer more favorable. The prevalence of pericardial metastasis is expected to increase as well. As such, it is necessary to discuss similar case encounters and establish appropriate treatment.
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http://dx.doi.org/10.12659/AJCR.932239DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8197445PMC
June 2021

Alpha-fetoprotein-producing Colon Carcinoma with Rapidly Increasing Liver Metastases That Resulted in Death: A Case Report.

J Anus Rectum Colon 2021 28;5(1):100-106. Epub 2021 Jan 28.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, Higashihiroshima, Japan.

Alpha-fetoprotein (AFP) has been widely used as a tumor marker for detecting hepatocellular carcinoma and yolk sac tumors. Recently, cases of gastrointestinal cancer with elevated serum AFP levels have been reported. However, AFP-producing colon cancer is considered rarer than other AFP-producing gastrointestinal cancers. In this study, we report on a case of a 47-year-old woman who was diagnosed with sigmoid colon cancer and underwent sigmoidectomy and lymph node dissection. Postoperative adjuvant chemotherapy (AC) was performed after the curative surgery. After the seventh course of AC, multiple liver masses and enlarged systemic lymph nodes were detected; these were later diagnosed as liver metastases from sigmoid colon cancer. Laboratory examination revealed high AFP levels (14,657.8 ng/mL). After confirming the recurrence, her condition worsened rapidly, and she eventually died 8 months after the operation. Autopsy and histopathological findings showed that the liver mass was positive for AFP staining, but the sigmoid colon cancer tissue was not. We then determined that liver metastases of the colon cancer were more likely than germ cell carcinoma according to the clinical course and pathological findings. We assumed that colon cancer cells can rapidly expand by dedifferentiation, and we diagnosed AFP-producing colon cancer with liver metastases. Despite curative surgery and AC for AFP-producing colon cancer, the patient died of liver and systemic lymph node metastases.
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http://dx.doi.org/10.23922/jarc.2020-038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7843138PMC
January 2021

Safety and Recipient Satisfaction of Propofol Sedation in Outpatient Endoscopy: A 24-Hour Prospective Investigation Using a Questionnaire Survey.

Clin Endosc 2021 May 11;54(3):340-347. Epub 2020 Dec 11.

Department of Gastroenterology, Sendai City Medical Center, Sendai, Japan.

Background/aims: The aim of this study was to evaluate the safety of sedation with propofol as an alternative to benzodiazepine drugs in outpatient endoscopy.

Methods: In this prospective study, examinees who underwent outpatient endoscopy under propofol sedation and submitted a nextday questionnaire with providing informed consent were evaluated. Periprocedural acute responses, late adverse events within 24 hours, and examinee satisfaction were evaluated.

Results: Among the 4,122 patients who received propofol in the 17,978 outpatient-based endoscopic examinations performed between November 2016 and March 2018, 2,305 eligible examinees (esophagogastroduodenoscopy for 1,340, endoscopic ultrasonography for 945, and total colonoscopy for 20) were enrolled, and their responses to a questionnaire were analyzed. The mean propofol dose was 69.6±24.4 mg (range, 20-200 mg). Diazepam, midazolam, and/or pentazocine in combination with propofol was administered to 146 examinees. Mild oxygen desaturation was observed in 59 examinees (2.6%); and mild bradycardia, in 2 (0.09%). Other severe reactions or late events did not occur. After eliminating 181 invalid responses, 97.7% (2,065/2,124) of the patients desired propofol sedation in future examinations.

Conclusion: Propofol sedation was found to be safe-without severe adverse events or accidents-for outpatient endoscopy on the basis of the patients' next-day self-evaluation. Given the high satisfaction level, propofol sedation might be an ideal tool for painless endoscopic screening.
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http://dx.doi.org/10.5946/ce.2020.138DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8182244PMC
May 2021

Cholangioscopy- versus fluoroscopy-guided transpapillary mapping biopsy for preoperative evaluation of extrahepatic cholangiocarcinoma: a prospective randomized crossover study.

Surg Endosc 2020 Nov 3. Epub 2020 Nov 3.

Department of Gastroenterology, Sendai City Medical Center, 5-22-1, Tsurugaya, Miyagino-ku, Sendai, 983-0824, Japan.

Background: To evaluate the lateral extent of extrahepatic cholangiocarcinoma, the value of cholangioscopy-guided mapping biopsy (CMB) compared with that of fluoroscopy-guided mapping biopsy (FMB) remains unknown. The aim of this study was to compare these two techniques.

Methods: In this prospective, randomized, crossover study, both CMB and FMB techniques were performed for all patients in a randomized order. Target sites for the mapping biopsy were determined based on resection lines of possible surgical procedures. At least two biopsy strokes were attempted at each target site. The primary outcome was the rate of site-based successful biopsies, which was defined as acquisition of epithelium-containing material appropriate for diagnosing benignancy/malignancy from each site, regardless of amount of materials obtained from the same site.

Results: Between September 2016 and October 2018, 28 patients (16 distal bile duct cancer and 12 perihilar bile duct cancer) were enrolled and divided into two groups of 14 patients: CMB first and FMB first. Although all 118 target sites could be approached using CMB, FMB forceps reached only 71% of them with significantly poor accessibility to the B2/3 confluence. Since several materials were too small and did not contain epithelium, the overall rates of site-based successful biopsies were 78% (92/118) using CMB and 64% (76/118) using FMB (P = 0.031).

Conclusions: The rate of site-based successful biopsies using CMB was significantly higher than that using FMB when evaluated using specimens obtained from several biopsy strokes.
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http://dx.doi.org/10.1007/s00464-020-08141-yDOI Listing
November 2020

Value of repeated cytology for intraductal papillary mucinous neoplasms of the pancreas with high risk potential of malignancy: Is it a promising method for monitoring a malignant transformation?

Pancreatology 2020 Sep 28;20(6):1164-1174. Epub 2020 Jul 28.

Department of Gastroenterology, Sendai City Medical Center, Sendai, Japan.

Objectives: The efficacy of and indications for cytological reexamination to detect malignant changes in branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) have not been studied in detail. We conducted a retrospective study to evaluate the efficacy and indications of cytological reexamination by using pancreatic juice (repeated cytology) for BD-IPMNs.

Methods: Forty-five patients who underwent repeated cytology after a diagnosis of benignancy by using initial cytology were recruited for this study.

Results: Thirty-eight patients, excluding 7 patients with lack of surveillance period after the final cytology, were classified into Malignancy (n = 13) and Benignancy groups (n = 25) on the bases of the findings from resected specimens or changes in BD-IPMNs after repeated cytology. The sensitivity and specificity to detect malignant changes in BD-IPMNs by using repeated cytology were 62% and 100%, respectively. For the 12 patients with mural nodules (MNs) ≥ 5 mm (67% of them were malignant), the sensitivity was 50%, whereas, for the 26 patients without MNs ≥ 5 mm (19% of them were malignant), it was 80%. In addition, malignant changes in BD-IPMNs after initial cytology occurred in 62% of the patients with changes in the MNs and 27% of the patients with an increase in the cyst size.

Conclusion: Repeated cytology can play a role in the determination for surgery even after a diagnosis of benignancy by using initial cytology, especially for BD-IPMNs without MNs ≥5 mm. In addition, changes in the MNs or cyst size may be appropriate indications for repeated cytology.
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http://dx.doi.org/10.1016/j.pan.2020.05.021DOI Listing
September 2020

A safe and reliable technique for fascial closure without special devices after laparoscopic surgery.

Asian J Endosc Surg 2021 Jan 16;14(1):149-153. Epub 2020 Jul 16.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, Higashihiroshima, Japan.

Introduction: To prevent port-site hernia, we established a simple and low-cost closure method that uses a venous catheter needle and suture, without any other special devices.

Materials And Surgical Technique: We used the inner needle of a 16-G venous catheter and a 2-0 absorbable bladed suture. To evaluate the efficacy of this technique, the procedure time was noted and compared among three operators (an experienced surgeon and two inexperienced surgeons).

Discussion: The median suturing time was 60.5 seconds (range, 26-130 seconds) per incision. Even an unexperienced surgeon can close the fascia safely and quickly after some experience with the procedure.
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http://dx.doi.org/10.1111/ases.12809DOI Listing
January 2021

Peroral Cholangioscopy-guided Electrohydraulic Lithotripsy with a SpyGlass DS Versus a Conventional Digital Cholangioscope for Difficult Bile Duct Stones.

Intern Med 2020 Aug 8;59(16):1925-1930. Epub 2020 May 8.

Department of Gastroenterology, Sendai City Medical Center, Japan.

Objective Recently, a new digital peroral cholangioscopy (POCS) system, the SpyGlass DS (SpyDS), has been used for POCS-guided lithotripsy for difficult bile duct stones (DBDSs). The aim of this retrospective study was to compare the efficacy of SpyDS-guided electrohydraulic lithotripsy (EHL) for DBDS with that of a conventional digital cholangioscope. Methods Seventeen consecutive patients who had undergone POCS-guided EHL for DBDS with the SpyDS between October 2015 and January 2019 were enrolled in this study group (SpyDS group) using a prospectively maintained database. Fifteen other consecutive patients who had undergone POCS-guided EHL with a conventional digital cholangioscope (CHF-B260) just prior to the introduction of the SpyDS between December 2006 and September 2015 were analyzed as a control group (CHF group). The main outcome measurement was the total procedure time to complete stone removal. Results The rate of complete stone removal was 100% for both groups. The mean total procedure time for the SpyDS group was significantly shorter than that for the CHF group (67±30 minutes vs. 107±64 minutes, p=0.038). The mean number of endoscopic sessions for the SpyDS group was significantly lower than that for the CHF group (1.35±0.49 vs. 2.00±0.85, p=0.037). There were no significant differences in the rate of adverse events between the two groups. Conclusion The SpyDS appears useful for decreasing the procedure time and number of endoscopic sessions for complete stone removal in POCS-guided EHL for DBDS compared with a conventional digital cholangioscope.
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http://dx.doi.org/10.2169/internalmedicine.4463-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7492117PMC
August 2020

Inside Plastic Stents versus Metal Stents for Treating Unresectable Malignant Perihilar Biliary Obstructions: A Retrospective Comparative Study.

Clin Endosc 2020 Nov 4;53(6):735-742. Epub 2020 Mar 4.

Department of Gastroenterology, Sendai City Medical Center, Sendai, Japan.

Background/aims: The aim of this study was to evaluate outcomes of inside plastic stents (iPSs) versus those of metal stents (MSs) for treating unresectable perihilar malignant obstructions.

Methods: For all patients who underwent endoscopic suprapapillary placement of iPS(s) or MS(s) as the first permanent biliary drainage for unresectable malignant perihilar obstructions between January 2014 and August 2019, clinical outcomes using iPSs (n=20) and MSs (n=85), including clinical efficacy, adverse events, and time to recurrence of biliary obstruction (RBO), were retrospectively evaluated.

Results: There were no differences in clinical effectiveness (95% for the iPS group vs. 92% for the MS group, p=1.00). Procedure-related adverse events, including pancreatitis, acute cholangitis, acute cholecystitis, and death, were observed for 8% of the MS group, although no patient in the iPS group developed such adverse events. The median time to RBO was 561 days (95% confidence interval, 0-1,186 days) for iPSs and 209 days (127-291 days) for MSs, showing a significant difference (p=0.008).

Conclusion: Time to RBO after iPS placement was significantly longer than that after MS placement. IPSs, which are removable, unlike MSs, were an acceptable option.
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http://dx.doi.org/10.5946/ce.2020.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7719412PMC
November 2020

Long-term Outcomes of Endoscopic Papillary Large-balloon Dilation for Common Bile Duct Stones.

Intern Med 2020 Apr 29;59(7):891-899. Epub 2019 Nov 29.

Department of Gastroenterology, Sendai City Medical Center, Japan.

Objective Endoscopic papillary large-balloon dilation (EPLBD) for common bile duct (CBD) stone removal has been confirmed to be safe and effective in the short term. The long-term outcomes of EPLBD, which have not been sufficiently evaluated, were therefore investigated in this study. Methods For patients who had undergone endoscopic CBD stone removal with EPLBD between October 2011 and December 2015, follow-up surveys were conducted using a postal survey, telephone interview, or medical record review in August 2017. The main outcome measurement was the recurrence rate of CBD stones after complete stone removal with EPLBD in patients who received follow-up for more than one year. Risk factors for such recurrence were secondarily analyzed. Results Of the 98 patients treated using EPLBD, 93 (95%) were followed up after complete stone removal and analyzed for the long-term outcomes. During the mean follow-up period of 33.7±16.6 months, CBD stones recurred in 16 patients (17%) with a mean interval of 12.7±12.7 months. Univariate analyses showed that a large stone size, multiple stones, a large distal CBD diameter, and a history of cholecystectomy were significant risk factors for stone recurrence (p=0.022, 0.013, 0.001 and 0.035, respectively). The large distal CBD diameter was the only significant risk factor for stone recurrence in a multivariate analysis (hazard ratio, 1.227; p=0.031). Conclusion The long-term outcomes of EPLBD for CBD stones, including the rate of stone recurrence, were found to be acceptable. A large distal CBD diameter was an independent risk factor for stone recurrence.
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http://dx.doi.org/10.2169/internalmedicine.3881-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7184081PMC
April 2020

Predictive Value of Localized Stenosis of the Main Pancreatic Duct for Early Detection of Pancreatic Cancer.

Clin Endosc 2019 Nov 20;52(6):588-597. Epub 2019 Nov 20.

Department of Gastroenterology, Sendai City Medical Center, Sendai, Japan.

Background/aims: In this study, we aimed to evaluate the predictive value of localized stenosis of the main pancreatic duct (MPD) for early detection of pancreatic cancer.

Methods: Among 689 patients who underwent endoscopic retrograde pancreatography from January 2008 to September 2018, 19 patients with MPD findings were enrolled. These patients showed findings for indicating suspicious pancreatic cancer at an early stage (FiCE); FiCE was defined as a single, localized stenosis in the MPD without a detectable mass (using any other imaging methods) and without other pancreatic diseases, such as definite chronic pancreatitis, intraductal papillary mucinous neoplasm, and autoimmune pancreatitis. Final diagnoses were established by examining resected specimens or through follow-up examinations after an interval of >5 years.

Results: Among 19 patients with FiCE, 11 underwent surgical resection and 8 were evaluated after a >5-year observation period. The final diagnosis of the MPD stenosis was judged to be pancreatic cancer in 9 patients (47%), including 3 with intraepithelial cancer, and to be a non-neoplastic change in 10. The sensitivity, specificity, and accuracy of preoperative pancreatic juice cytology were 75%, 100%, and 88%, respectively.

Conclusion: The predictive value of FiCE for pancreatic cancer prevalence was 47%. Histological confirmation with pancreatic juice cytology is necessary before surgical resection.
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http://dx.doi.org/10.5946/ce.2019.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6900300PMC
November 2019

Mucinous nonneoplastic cyst of the pancreas penetrates the colon causing infection: a case report.

J Med Case Rep 2019 Aug 10;13(1):264. Epub 2019 Aug 10.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, 513 Jike, Saijo-cho, Higashihiroshima, Hiroshima, 739-0041, Japan.

Background: Mucinous nonneoplastic cyst of the pancreas is a rare disease defined as a cystic lesion lined with mucinous epithelium, supported by hypocellular stroma and not communicating with the pancreatic ducts. Mucinous nonneoplastic cyst of the pancreas has no malignant potential and does not require surgical resection or surveillance. However, its preoperative differentiation from other cystic lesions of the pancreas is difficult because of several overlapping clinical, radiological, and biochemical features. We report a rare case of large mucinous nonneoplastic cyst of the pancreas in which surgery was required due to infection and the possibility of malignancy.

Case Presentation: A 75-year-old Japanese man was found to have a pancreatic cyst in 2006 while undergoing postoperative evaluation for colon cancer. In 2015, the cyst ruptured, and it was treated conservatively. In 2017, he fell down on a road with a fever of 40 °C and was transported emergently to a nearby hospital. Enhanced computed tomography revealed a cystic lesion in the body of the pancreas measuring 119 mm × 100 mm and an adjacent left renal cyst measuring 63 mm in diameter. The wall of the pancreatic cyst was thickened. Magnetic resonance imaging demonstrated a liquid surface in the pancreatic cyst. Pancreatic cyst infection was diagnosed as the source of infection. However, identification of the organism was difficult. Furthermore, due to the increase in the size and wall thickness of the cyst, it was unclear whether the cystic mass was neoplastic with malignant potential. For these reasons, the patient underwent distal pancreatectomy and splenectomy with deroofing of the left renal cyst. Intraoperatively, the pancreatic cyst adhered to the descending colon, and partial resection of the colon was added. Pathologic analysis of the resected cyst demonstrated a simple cyst lined by mucinous epithelium. There was no underlying stromal condensation or epithelial dysplasia, and communication with the native pancreatic ducts was not observed. Based on the operative and histological findings, a final diagnosis of mucinous nonneoplastic cyst of the pancreas with colonic communication was made. The colonic fistula was presumed to be the source of infection.

Conclusion: Mucinous nonneoplastic cyst of the pancreas is generally benign and requires little follow-up, but large cysts may penetrate other organs and cause severe complications.
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http://dx.doi.org/10.1186/s13256-019-2160-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6689156PMC
August 2019

Endoscopic Ultrasonography-Guided Gallbladder Drainage as a Treatment Option for Acute Cholecystitis after Metal Stent Placement in Malignant Biliary Strictures.

Clin Endosc 2019 May 15;52(3):262-268. Epub 2019 Mar 15.

Department of Gastroenterology, Sendai City Medical Center, Sendai, Japan.

Background/aims: It is often difficult to manage acute cholecystitis after metal stent (MS) placement in unresectable malignant biliary strictures. The aim of this study was to evaluate the feasibility of endoscopic ultrasonography-guided gallbladder drainage (EUS-GBD) for acute cholecystitis.

Methods: The clinical outcomes of 10 patients who underwent EUS-GBD for acute cholecystitis after MS placement between January 2011 and August 2018 were retrospectively evaluated. The procedural outcomes of percutaneous transhepatic gallbladder drainage (PTGBD) with tube placement (n=11 cases) and aspiration (PTGBA) (n=27 cases) during the study period were evaluated as a reference.

Results: The technical success and clinical effectiveness rates of EUS-GBD were 90% (9/10) and 89% (8/9), respectively. Severe bile leakage that required surgical treatment occurred in one case. Acute cholecystitis recurred after stent dislocation in 38% (3/8) of the cases. Both PTGBD and PTGBA were technically successful in all cases without severe adverse events and clinically effective in 91% and 63% of the cases, respectively.

Conclusion: EUS-GBD after MS placement was a feasible option for treating acute cholecystitis. However, it was a rescue technique following the established percutaneous intervention in the current setting because of the immature technical methodology, including dedicated devices, which need further development.
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http://dx.doi.org/10.5946/ce.2018.183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6547349PMC
May 2019

α-toxin impairs granulocyte colony-stimulating factor receptor-mediated granulocyte production while triggering septic shock.

Commun Biol 2019 31;2:45. Epub 2019 Jan 31.

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima, 770-8514 Japan.

During bacterial infection, granulocyte colony-stimulating factor (G-CSF) is produced and accelerates neutrophil production from their progenitors. This process, termed granulopoiesis, strengthens host defense, but α-toxin impairs granulopoiesis via an unknown mechanism. Here, we tested whether G-CSF accounts for the α-toxin-mediated impairment of granulopoiesis. We find that α-toxin dramatically accelerates G-CSF production from endothelial cells in response to Toll-like receptor 2 (TLR2) agonists through activation of the c-Jun N-terminal kinase (JNK) signaling pathway. Meanwhile, α-toxin inhibits G-CSF-mediated cell proliferation of Ly-6G neutrophils by inducing degradation of G-CSF receptor (G-CSFR). During sepsis, administration of α-toxin promotes lethality and tissue injury accompanied by accelerated production of inflammatory cytokines in a TLR4-dependent manner. Together, our results illustrate that α-toxin disturbs G-CSF-mediated granulopoiesis by reducing the expression of G-CSFR on neutrophils while augmenting septic shock due to excess inflammatory cytokine release, which provides a new mechanism to explain how pathogenic bacteria modulate the host immune system.
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http://dx.doi.org/10.1038/s42003-019-0280-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6355902PMC
April 2020

Prognostic Nutritional Index Predicts Treatment Outcomes following Palliative Surgery for Colorectal Adenocarcinoma.

J Anus Rectum Colon 2017 25;1(4):118-124. Epub 2018 May 25.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, Hiroshima, Japan.

Objectives: Palliative surgeries such as stoma creation and bypass are effective for relieving symptoms related to incurable abdominal malignancies; however, these methods are controversial in patients with severe metastatic disease or poor pre-surgical health. The aim of this study was to examine the clinical significance of the prognostic nutritional index (PNI) in evaluations for palliative surgery.

Methods: We retrospectively analyzed data from 37 patients who underwent palliative surgery for histologically-proven colorectal adenocarcinoma from 2009 to 2015. We investigated both risk factors for postoperative complications and prognostic factors. We used a PNI cutoff value of 40, as defined by previous studies.

Results: The reason for surgery was stenosis in 18 patients, obstruction in 12, fistula in 5, and bleeding in 2. Bypass was performed in 10 cases, ileostomy in 5, and colostomy in 22. Postoperative morbidity and mortality occurred in 9 and 2 patients, respectively. Median overall survival time was 8.9 months. Only low PNI correlated with postoperative complications at trend-level (p=0.07), and the 2 patients with mortality were classified as PNI-low. The presence of ascites (p=0.003) and PNI (p=0.02) were identified as independent prognostic factors.

Conclusions: PNI could be used as an objective marker for deciding whether to proceed with palliative surgery, independent of the extent of metastatic disease.
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http://dx.doi.org/10.23922/jarc.2017-016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6768688PMC
May 2018

Acid Sphingomyelinase Promotes Cellular Internalization of Iota-Toxin.

Toxins (Basel) 2018 05 20;10(5). Epub 2018 May 20.

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.

iota-toxin is a binary actin-ADP-ribosylating toxin composed of the enzymatic component Ia and receptor binding component Ib. Ib binds to a cell surface receptor, forms Ib oligomer in lipid rafts, and associates with Ia. The Ia-Ib complex then internalizes by endocytosis. Here, we showed that acid sphingomyelinase (ASMase) facilitates the cellular uptake of iota-toxin. Inhibitions of ASMase and lysosomal exocytosis by respective blockers depressed cell rounding induced by iota-toxin. The cytotoxicity of the toxin increased in the presence of Ca in extracellular fluids. Ib entered target cells in the presence but not the absence of Ca. Ib induced the extracellular release of ASMase in the presence of Ca. ASMase siRNA prevented the cell rounding induced by iota-toxin. Furthermore, treatment of the cells with Ib resulted in the production of ceramide in cytoplasmic vesicles. These observations showed that ASMase promotes the internalization of iota-toxin into target cells.
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http://dx.doi.org/10.3390/toxins10050209DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5983265PMC
May 2018

Causes and Prognosis of Unilateral and Bilateral Optic Disc Swelling.

Neuroophthalmology 2017 Aug 10;41(4):187-191. Epub 2017 Apr 10.

Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Sakyo, Kyoto, Japan.

The authors reviewed 93 consecutive cases with optic disc swelling (ODS) to compare clinical manifestations and prognosis among the causes. Among unilateral ODS patients ≥50 years old and without pain, anterior ischaemic optic neuropathy accounted for 87.5%. Furthermore, papilloedema (PE) presented unilateral ODS with an atrophic or hypoplastic disc in the opposite eye. Despite no differences for age and initial visual acuity between PE and pseudopapilloedema, the two main causes of bilateral ODS, some PE patients showed poor visual prognosis. Understanding differences in frequencies and clinical features of ODS related to cause and age group can help to accurately determine cause and predict outcome.
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http://dx.doi.org/10.1080/01658107.2017.1299766DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5762143PMC
August 2017

Clinical outcomes of Clutch Cutter endoscopic submucosal dissection for older patients with early gastric cancer.

World J Gastrointest Oncol 2017 Oct;9(10):416-422

Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.

Aim: To evaluate the clinical outcome of endoscopic submucosal dissection using the Clutch Cutter (ESDCC) in older patients.

Methods: We reviewed 232 consecutive patients with early gastric cancer who underwent ESDCC between June 2010 and February 2014 at Aso Iizuka Hospital. We divided patients into two groups according to age: Older patients (> 80 years, = 64) and non-older patients (≤ 80 years, = 168). We retrospectively compared the prevalence rates of pre-existing comorbidities, anticoagulant therapy, resection, mean duration of hospitalization, incidence of ESDCC-related complications, change in performance status (PS) before and after ESDCC, and financial cost of admission.

Results: The older group comprised 64 patients with a mean age of 84.1 years, and the non-older group comprised 168 patients with a mean age of 69.5 years. Older patients had significantly more pre-existing comorbidities than did non-older patients, specifically heart disease ( < 0.05). The resection rate in non-older patients was significantly higher than that in older patients (100% 95.3%, = 0.02). There were no significant differences between the older and non-older groups in the incidence of ESDCC-related complications (., postoperative bleeding and perforation) and the post-ESDCC change in PS. There were also no significant differences between the older and non-older groups in the mean duration of hospitalization (11.4 and 10.7 d, respectively) and financial cost of admission (657040 JPY and 574890 JPY, respectively).

Conclusion: ESDCC has a good clinical outcome in older patients.
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http://dx.doi.org/10.4251/wjgo.v9.i10.416DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5648985PMC
October 2017

Sole vibration improves locomotion through the recovery of joint movements in a mouse cast model.

PLoS One 2017 17;12(10):e0186189. Epub 2017 Oct 17.

Department of Orthopedic Surgery, Nakamura Hospital, Nogata, Fukuoka, Japan.

We investigated the effects of a vibratory stimulus on the plantar surface of the hind limb for motor, sensory, and locomotive function using a mouse cast model. The right knee joint of C57BL/6 male mice (7 weeks, 20 g, n = 31) was flexed with aluminum splint and tape for 6 weeks. These mice were randomly divided into 2 groups (control group, n = 11 and vibration group, n = 12). The mice in the vibration group received vibration on the sole of the ankle for 15 minutes per day, 5 days per week. After the knee joint cast was removed, we measured the range of motion (ROM) of both knee and ankle joints and the sensory threshold of the sole. Further, both walking and swimming movements were analyzed with a digital video. The sole vibration did not affect the passive ROM of the knee joint and sensory threshold after cast removal. However, it increased the ankle dorsiflexion range and improved free walking, swimming, and active movement of the knee joint. In conclusion, we show that the vibration recovered both walking and swimming movements, which resulted from improvements in both the passive ankle dorsiflexion and active knee movement.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0186189PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5645094PMC
October 2017

Hemorrhagic Cholecystitis in a Patient on Maintenance Dialysis.

Case Rep Gastroenterol 2017 May-Aug;11(2):488-493. Epub 2017 Aug 17.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, Higashihiroshima, Japan.

The present paper describes a case of hemorrhagic cholecystitis in a patient on maintenance dialysis. The patient presented with right upper quadrant abdominal pain. Computed tomography revealed swelling of the gallbladder, high- and isodensity contents of the gallbladder, and high-density stone in the gallbladder neck. He was hospitalized for suspected acute cholecystitis. After hospitalization, his levels of total bilirubin, aspartate aminotransferase, and alanine aminotransferase increased. T2-weighted magnetic resonance imaging showed low-intensity contents expanded to include a wide area from the common bile duct to the cystic duct and gallbladder neck. Endoscopic retrograde cholangiopancreatography revealed clotting from the duodenal papilla. After cannulation of the bile duct, old blood and pus began to flow from the mammary papilla, and an endoscopic nasobiliary drainage tube was placed. After his liver function had improved, the patient underwent laparoscopic cholecystectomy. His sample revealed that the gallbladder was filled with blood clots and stones. His postoperative course was uneventful and he was discharged on day 19 after the procedure. Although hemorrhagic cholecystitis is rare, it should be considered as a differential diagnosis for patients on dialysis who have acute abdominal symptoms.
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http://dx.doi.org/10.1159/000479497DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5624269PMC
August 2017

Delta-toxin from Clostridium perfringens perturbs intestinal epithelial barrier function in Caco-2 cell monolayers.

Biochim Biophys Acta Biomembr 2018 Feb 5;1860(2):428-433. Epub 2017 Oct 5.

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan. Electronic address:

Clostridium perfringens delta-toxin is a β-barrel-pore-forming toxin (β-PFT) and a presumptive virulence factor of type B and C strains, which are causative organisms of fatal intestinal diseases in animals. We showed previously that delta-toxin causes cytotoxicity via necrosis in sensitive cells. Here, we examined the effect of delta-toxin on intestinal membrane integrity. Delta-toxin led to a reduction in transepithelial electrical resistance (TEER) and increased the permeability of fluorescence isothiocyanate-conjugated dextran in human intestinal epithelial Caco-2 cells without changing the tight junction proteins, such as zonula occludens-1 (ZO-1), occludin, and claudin-1. On the other hand, delta-toxin reduced the cellular levels of adherence junction protein E-cadherin before cell injury. A disintegrin and metalloprotease (ADAM) 10 facilitates E-cadherin cleavage and was identified as the cellular receptor for alpha-toxin, a β-PFT produced by Staphylococcus aureus. ADAM10 inhibitor (GI254023X) blocked the toxin-induced decrease in TEER and cleavage of E-cadherin. Delta-toxin enhanced ADAM10 activity in a dose- and time-dependent manner. Furthermore, delta-toxin colocalized with ADAM10. These results indicated that ADAM10 plays a key role in delta-toxin-induced intestinal injury.
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http://dx.doi.org/10.1016/j.bbamem.2017.10.003DOI Listing
February 2018

Endoscopic submucosal dissection of gastric adenomas using the clutch cutter.

World J Gastrointest Endosc 2017 Jul;9(7):334-340

Kazuya Akahoshi, Masaru Kubokawa, Junya Gibo, Shigeki Osada, Kayo Tokumaru, Eriko Yamaguchi, Hiroko Ikeda, Takao Sato, Kazuaki Miyamoto, Yusuke Kimura, Yuki Shiratsuchi, Kazuaki Akahoshi, Department of Gastroenterology, Aso Iizuka Hospital, Iizuka 820-8505, Japan.

Aim: To evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) using the clutch cutter (CC) (ESD-CC) for gastric adenoma (GA).

Methods: From June 2007 to August 2015, 122 consecutive patients with histological diagnoses of GA from specimens resected by ESD-CC were enrolled in this prospective study. The CC was used for all ESD steps (marking, mucosal incision, submucosal dissection, and hemostatic treatment), and its therapeutic efficacy and safety were assessed.

Results: Both the resection rate and the R0 resection rate were 100% (122/122). The mean surgical time was 77.4 min, but the time varied significantly according to tumor size and location. No patients suffered perforation. Post-ESD-CC bleeding occurred in six cases (4.9%) that were successfully resolved by endoscopic hemostatic treatment.

Conclusion: ESD-CC is a technically efficient, safe, and easy method for resecting GA.
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http://dx.doi.org/10.4253/wjge.v9.i7.334DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5507825PMC
July 2017

Clostridium perfringens α-toxin impairs erythropoiesis by inhibition of erythroid differentiation.

Sci Rep 2017 07 12;7(1):5217. Epub 2017 Jul 12.

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima, 770-8514, Japan.

Clostridium perfringens α-toxin induces hemolysis of erythrocytes from various species, but it has not been elucidated whether the toxin affects erythropoiesis. In this study, we treated bone marrow cells (BMCs) from mice with purified α-toxin and found that TER119 erythroblasts were greatly decreased by the treatment. A variant α-toxin defective in enzymatic activities, phospholipase C and sphingomyelinase, had no effect on the population of erythroblasts, demonstrating that the decrease in erythroblasts was dependent of its enzymatic activities. α-Toxin reduced the CD71TER119 and CD71TER119 cell populations but not the CD71TER119 cell population. In addition, α-toxin decreased the number of colony-forming unit erythroid colonies but not burst-forming unit erythroid colonies, indicating that α-toxin preferentially reduced mature erythroid cells compared with immature cells. α-Toxin slightly increased annexinV cells in TER119 cells. Additionally, simultaneous treatment of BMCs with α-toxin and erythropoietin greatly attenuated the reduction of TER119 erythroblasts by α-toxin. Furthermore, hemin-induced differentiation of human K562 erythroleukemia cells was impaired by α-toxin, whereas the treatment exhibited no apparent cytotoxicity. These results suggested that α-toxin mainly inhibited erythroid differentiation. Together, our results provide new insights into the biological activities of α-toxin, which might be important to understand the pathogenesis of C. perfringens infection.
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http://dx.doi.org/10.1038/s41598-017-05567-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5507896PMC
July 2017

CIRCINATE PARTITION-LIKE FINDINGS ON CONE MOSAIC IMAGED BY ADAPTIVE OPTICS SCANNING LASER OPHTHALMOSCOPY IN EYES WITH INNER NUCLEAR LAYER MICROCYSTIC CHANGES.

Retin Cases Brief Rep 2019 Summer;13(3):232-237

Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.

Purpose: To report cases that showed partition-like, dark areas in the cone mosaic on adaptive optics scanning laser ophthalmoscopy (AO-SLO) images in eyes with inner nuclear layer (INL) microcystic changes.

Methods: Eyes with INL microcystic changes were imaged by prototype AO-SLO.

Results: An eye with Leber hereditary optic neuropathy, an eye with traumatic optic neuropathy, and an eye with retinitis pigmentosa that showed microcystic lesions in the INL were imaged by AO-SLO. The images revealed characteristic, dark, partition-like lesions in the cone mosaic of all the eyes in areas where microcystic changes in the INL were shown by spectral domain optical coherence tomography. The AO-SLO findings in eyes with optic neuropathy were quite similar in shape and size to those seen in eyes with retinitis pigmentosa.

Conclusion: We report cases that manifest dark, partition-like areas in the cone mosaic on AO-SLO images. Microcystic lesions in the INL may affect the images of the cone mosaic.
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http://dx.doi.org/10.1097/ICB.0000000000000564DOI Listing
June 2019

Cellular Uptake of Clostridium botulinum C2 Toxin Requires Acid Sphingomyelinase Activity.

Infect Immun 2017 04 23;85(4). Epub 2017 Mar 23.

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro, Tokushima, Japan.

C2 toxin consists of an enzyme component (C2I) and a binding component (C2II). Activated C2II (C2IIa) binds to a cell receptor, giving rise to lipid raft-dependent oligomerization, and it then assembles with C2I. The whole toxin complex is then endocytosed into the cytosol, resulting in the destruction of the actin cytoskeleton and cell rounding. Here, we showed that C2 toxin requires acid sphingomyelinase (ASMase) activity during internalization. In this study, inhibitors of ASMase and lysosomal exocytosis blocked C2 toxin-induced cell rounding. C2IIa induced Ca influx from the extracellular medium to cells. C2 toxin-induced cell rounding was enhanced in the presence of Ca ASMase was released extracellularly when cells were incubated with C2IIa in the presence of Ca Small interfering RNA (siRNA) knockdown of ASMase reduced C2 toxin-induced cell rounding. ASMase hydrolyzes sphingomyelin to ceramide on the outer leaflet of the membrane at acidic pH. Ceramide was detected in cytoplasmic vesicles containing C2IIa. These results indicated that ASMase activity is necessary for the efficient internalization of C2 toxin into cells. Inhibitors of ASMase may confer protection against infection.
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http://dx.doi.org/10.1128/IAI.00966-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5364297PMC
April 2017

Successful resection of liver metastasis detected by exacerbation of skin symptom in a patient with dermatomyositis accompanied by rectal cancer: a case report and literature review.

Surg Case Rep 2017 Dec 4;3(1). Epub 2017 Jan 4.

Department of Surgery, National Hospital Organization Higashihiroshima Medical Center, 513, Jike, Saijyo-cho, Higashihiroshima, Hiroshima, 739-0041, Japan.

Background: Dermatomyositis (DM) is a rare syndrome that belongs to the group of idiopathic inflammatory myopathies. The association between DM and malignancy is well recognized, and the severity of DM symptoms has been linked to the progression of metastatic disease.

Case Presentation: We report the case of a 42-year-old man that was diagnosed with dermatomyositis (DM) and rectal cancer. Proctectomy was performed, and DM symptoms were resolved postoperatively. One year and 9 months after the surgery, liver metastasis occurred accompanied by the exacerbation of DM symptom. Partial resection of the liver was performed, and postoperative course was uneventful. DM symptoms improved postoperatively, and no evidence of cancer recurrence or DM symptoms was observed 2 years after the second surgery. To date, few reports have described recurring cases of DM accompanied by colorectal cancer in detail. We reviewed four similar cases that were reported poor prognoses with treatment resistance. However, our case report demonstrates good long-term results with resection of metastatic lesion.

Conclusions: It is important to check the exacerbation of DM symptoms, as this symptom sometimes preceded cancer relapse during the follow-up of our patient with DM and colorectal cancer.
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http://dx.doi.org/10.1186/s40792-016-0281-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5214766PMC
December 2017

Structural and Functional Analyses in Nonarteritic Anterior Ischemic Optic Neuropathy: Optical Coherence Tomography Angiography Study.

J Neuroophthalmol 2017 06;37(2):140-148

Department of Ophthalmology and Visual Sciences, Kyoto University, Kyoto, Japan.

Background: Retinal and optic disc perfusion in nonarteritic anterior ischemic optic neuropathy (NAION) is incompletely understood. Our aim was to investigate the characteristics of the microvascular structures at the peripapillary area and optic disc, and their associations with retinal structure and function in patients with NAION.

Methods: We conducted a prospective, observational case series study. Thirty-four eyes, consisting of 15 NAION eyes and 19 normal eyes, were included. Optical coherence tomography (OCT) angiography was used to measure the vessel densities in the peripapillary superficial retina and whole-depth mode inside the optic disc. Measurement of circumpapillary retinal nerve fiber layer (cpRNFL) thickness was performed using OCT. Sectorial division analysis of cpRNFL was performed by eliminating the influences of the difference in disc rotation between OCT images and OCT angiography images.

Results: The vessel densities of peripapillary retina and inside the optic disc were significantly reduced in the NAION compared to the normal (both P < 0.001). Both the severity of visual field defect and cpRNFL thinning were significantly associated with the peripapillary vessel density (P = 0.006, P = 0.046), but not with the optic disc vessel density (P = 0.981, P = 0.856). cpRNFL and peripapillary vessel density showed reduction predominantly in the superior sectors, corresponding to the visual field defect. However, the correlations showed discrepancy of the sectors.

Conclusions: The microvascular structures in the peripapillary retina and optic disc were reduced, but the cpRNFL thinning was associated with vessel density only in the peripapillary retina, indicating that the vessel densities in the peripapillary retina and optic disc may be differently affected in the pathological process of NAION.
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http://dx.doi.org/10.1097/WNO.0000000000000470DOI Listing
June 2017

Clostridium perfringens α-Toxin Impairs Lipid Raft Integrity in Neutrophils.

Biol Pharm Bull 2016 ;39(10):1694-1700

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University.

Clostridium perfringens type A, a Gram-positive, anaerobic bacterium, causes gas gangrene. Recently, we reported that C. perfringens α-toxin blocked neutrophil differentiation in an enzyme activity-dependent manner to impair host innate immunity, which should be crucial for the pathogenesis of C. perfringens. However, the detailed mechanism remains unclear. Lipid rafts have been reported to be platforms for signaling molecules involved in the regulation of cell differentiation in many different cell types. In this study, we found that cell surface expression of a lipid raft marker, GM1 ganglioside, decreased in association with neutrophil differentiation by flow cytometry analysis and morphological observation. In vitro treatment of isolated mouse bone marrow cells with α-toxin or an α-toxin variant lacking phospholipase C and sphingomyelinase activities revealed that α-toxin increased the cell surface expression of GM1 ganglioside in an enzyme activity-dependent manner. C. perfringens infection also increased GM1 ganglioside levels in bone marrow myeloid cells. Moreover, treatment of bone marrow cells with methyl-β-cyclodextrin, a lipid raft-disrupting agent, impaired neutrophil differentiation. Together, our results suggest that the integrity of lipid rafts should be properly maintained during granulopoiesis, and α-toxin might perturb lipid raft integrity leading to the impairment of neutrophil differentiation.
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http://dx.doi.org/10.1248/bpb.b16-00444DOI Listing
January 2017

Clostridium perfringens α-Toxin Impairs Innate Immunity via Inhibition of Neutrophil Differentiation.

Sci Rep 2016 06 16;6:28192. Epub 2016 Jun 16.

Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.

Although granulopoiesis is accelerated to suppress bacteria during infection, some bacteria can still cause life-threatening infections, but the mechanism behind this remains unclear. In this study, we found that mature neutrophils in bone marrow cells (BMCs) were decreased in C. perfringens-infected mice and also after injection of virulence factor α-toxin. C. perfringens infection interfered with the replenishment of mature neutrophils in the peripheral circulation and the accumulation of neutrophils at C. perfringens-infected sites in an α-toxin-dependent manner. Measurements of bacterial colony-forming units in C. perfringens-infected muscle revealed that α-toxin inhibited a reduction in the load of C. perfringens. In vitro treatment of isolated BMCs with α-toxin (phospholipase C) revealed that α-toxin directly decreased mature neutrophils. α-Toxin did not influence the viability of isolated mature neutrophils, while simultaneous treatment of BMCs with granulocyte colony-stimulating factor attenuated the reduction of mature neutrophils by α-toxin. Together, our results illustrate that impairment of the innate immune system by the inhibition of neutrophil differentiation is crucial for the pathogenesis of C. perfringens to promote disease to a life-threatening infection, which provides new insight to understand how pathogenic bacteria evade the host immune system.
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http://dx.doi.org/10.1038/srep28192DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4910053PMC
June 2016

Quantitative comparison of disc rim color in optic nerve atrophy of compressive optic neuropathy and glaucomatous optic neuropathy.

Graefes Arch Clin Exp Ophthalmol 2016 Aug 26;254(8):1609-1616. Epub 2016 Apr 26.

Department of Ophthalmology and Visual Sciences, Kyoto University, 54 Shougoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.

Purpose: The purpose was to investigate an objective and quantitative method to estimate the redness of the optic disc neuroretinal rim, and to determine the usefulness of this method to differentiate compressive optic neuropathy (CON) from glaucomatous optic neuropathy (GON).

Methods: In our study there were 126 eyes: 40 with CON, 40 with normal tension glaucoma (NTG), and 46 normal eyes (NOR). Digital color fundus photographs were assessed for the redness of disc rim color using ImageJ software. We separately measured the intensity of red, green, and blue pixels from RGB images. Three disc color indices (DCIs), which indicate the redness intensity, were calculated through existing formulas.

Results: All three DCIs of CON were significantly smaller than those of NOR (P < 0.001). In addition, when compared with NTG, DCIs were also significantly smaller in CON (P < 0.05). A comparison of mild CON and mild NTG (mean deviation (MD) > -6 dB), in which the extent of retinal nerve fiber layer thinning is comparable, the DCIs of mild CON were significantly smaller than those of mild NTG (P < 0.05). In contrast, DCIs did not differ between moderate-to-severe stages of CON and NTG (MD ≤ -6 dB), though the retinal nerve fibers of CON were more severely damaged than those of NTG. To differentiate between mild CON and mild NTG, all AUROCs for the three DCIs were above 0.700.

Conclusions: A quantitative and objective assessment of optic disc color was useful in differentiating early-stage CON from GON and NOR.
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http://dx.doi.org/10.1007/s00417-016-3366-2DOI Listing
August 2016
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