炎症性腸疾患および再発性Clostridioides difficile感染症患者における糞便移植後の臨床的改善、便中腸内細菌叢・代謝産物の変化

藤田医科大

Risk factors for unsuccessful removal of central venous access ports implanted in the forearm of adult oncologic patients

Purpose: To evaluate the risk factors for unsuccessful removal of a central venous access port (CV port) implanted in the forearm of adult oncologic patients. Materials and methods: This study included 97 adult oncologic patients (51 males, 46 females; age range, 30–88 years; mean age, 63.7 years) in whom removal of a CV port implanted in the forearm was attempted at our hospital between January 2015 and May 2021. Gender, age at removal, body mass index, and diagnosis were examined as patient characteristics; and indwelling period, indwelling side, and indication for removal were examined as factors associated with removal of a CV port. These variables were compared between successful and unsuccessful cases using univariate analysis. Then, multivariate analysis was performed to identify independent risk factors for unsuccessful removal of a CV port using variables with a significant difference in the univariate analysis. A receiver-operating characteristics (ROC) curve was drawn for significant risk factors in the multivariate analysis and the Youden index was used to determine the optimum cut-off value for predicting unsuccessful removal of a CV port. Results: Removal of CV ports was successful in 79 cases (81.4%), but unsuccessful in 18 cases (18.6%) due to fixation of the catheter to the vessel wall. Multivariate logistic regression analysis showed that the indwelling period (odds ratio 1.048; 95% confidence interval 1.026–1.070; P  60 months had unsuccessful removal. Conclusion: The indwelling period is an independent risk factor for unsuccessful removal of a CV port implanted in the forearm of adult oncologic patients, with a cut-off of 41 months

Outer Membrane Vesicles of Helicobacter pylori TK1402 are Involved in Biofilm Formation

<p>Abstract</p> <p>Background</p> <p><it>Helicobacter pylori </it>forms biofilms on glass surfaces at the air-liquid interface in <it>in vitro </it>batch cultures; however, biofilms of <it>H. pylori </it>have not been well characterized. In the present study, we analyzed the ability of <it>H. pylori </it>strains to form biofilms and characterized the underlying mechanisms of <it>H. pylori </it>biofilm formation.</p> <p>Results</p> <p>Strain TK1402 showed strong biofilm forming ability relative to the other strains in Brucella broth supplemented with 7% FCS. The strong biofilm forming ability of TK1402 is reflected the relative thickness of the biofilms. In addition, outer membrane vesicles (OMV) were detected within the matrix of only the TK1402 biofilms. Biofilm formation was strongly correlated with the production of OMV in this strain. We further observed that strain TK1402 did not form thick biofilms in Brucella broth supplemented with 0.2% β-cyclodextrin. However, the addition of the OMV-fraction collected from TK1402 could enhance biofilm formation.</p> <p>Conclusion</p> <p>The results suggested that OMV produced from TK1402 play an important role in biofilm formation in strain TK1402.</p

Percutaneous drainage of psoas and iliopsoas muscle abscesses with a one-step technique under real-time computed tomography fluoroscopic guidance

PURPOSE : To evaluate the utility and safety of drainage catheter installation for psoas/iliopsoas muscle abscesses using a one-step technique under the guidance of real-time computed tomography (CT) fluoroscopy. MATERIALS and METHODS : Ten psoas or iliopsoas muscle abscesses in 7 patients that were treated with percutaneous drainage were included in this study. All drainage procedures were carried out using a one-step technique under real-time CT fluoroscopic guidance. RESULTS : The drainage catheter insertion was performed successfully with the one-step technique in all lesions. Improvements in the patients’ symptoms and blood test results were seen after the drainage procedure in all cases. In addition, postoperative CT scans demonstrated that the abscesses had reduced in size or disappeared in all but one patient, who was transferred to another institution while the drainage catheter was still in place. No major complications were seen in any case. CONCLUSION : The one-step procedure is simple to perform. The percutaneous drainage of psoas or iliopsoas muscle abscesses with the one-step technique under real-time CT fluoroscopic guidance is accurate and safe. Moreover, compared with the two-step technique the one-step procedure results in a shorter drainage procedure and exposes the patient and operator to lower amounts of radiation

Autonomous learning of ball trapping in the four-legged robot league

Abstract. This paper describes an autonomous learning method used with real robots in order to acquire ball trapping skills in the four-legged robot league. These skills involve stopping and controlling an oncoming ball and are essential to passing a ball to each other. We rst prepare some training equipment and then experiment with only one robot. The robot can use our method to acquire these necessary skills on its own, much in the same way that a human practicing against a wall can learn the proper movements and actions of soccer on his/her own. We also experiment with two robots, and our ndings suggest that robots communicating between each other can learn more rapidly than those without any communication.

Loss of Bacitracin Resistance Due to a Large Genomic Deletion among Bacillus anthracis Strains

Bacillus anthracis is a Gram-positive endospore-forming bacterial species that causes anthrax in both humans and animals. In Zambia, anthrax cases are frequently reported in both livestock and wildlife, with occasional transmission to humans, causing serious public health problems in the country. To understand the genetic diversity of B. anthracis strains in Zambia, we sequenced and compared the genomic DNA of B. anthracis strains isolated across the country. Single nucleotide polymorphisms clustered these strains into three groups. Genome sequence comparisons revealed a large deletion in strains belonging to one of the groups, possibly due to unequal crossing over between a pair of rRNA operons. The deleted genomic region included genes conferring resistance to bacitracin, and the strains with the deletion were confirmed with loss of bacitracin resistance. Similar deletions between rRNA operons were also observed in a few B. anthracis strains phylogenetically distant from Zambian strains. The structure of bacitracin resistance genes flanked by rRNA operons was conserved only in members of the Bacillus cereus group. The diversity and genomic characteristics of B. anthracis strains determined in this study would help in the development of genetic markers and treatment of anthrax in Zambia. IMPORTANCE Anthrax is caused by Bacillus anthracis, an endospore-forming soil bacterium. The genetic diversity of B. anthracis is known to be low compared with that of Bacillus species. In this study, we performed whole-genome sequencing of Zambian isolates of B. anthracis to understand the genetic diversity between closely related strains. Comparison of genomic sequences revealed that closely related strains were separated into three groups based on single nucleotide polymorphisms distributed throughout the genome. A large genomic deletion was detected in the region containing a bacitracin resistance gene cluster flanked by rRNA operons, resulting in the loss of bacitracin resistance. The structure of the deleted region, which was also conserved among species of the Bacillus cereus group, has the potential for both deletion and amplification and thus might be enabling the species to flexibly control the level of bacitracin resistance for adaptive evolution

Clinical response and changes in the fecal microbiota and metabolite levels after fecal microbiota transplantation in patients with inflammatory bowel disease and recurrent Clostridioides difficile infection

Objectives: We determined the efficacy of fecal microbiota transplantation (FMT) and subsequent changes in fecal microbiota and short-chain fatty acid (SCFA) levels in patients with ulcerative colitis (UC), Crohn’s disease (CD), and recurrent Clostridioides difficile infection (rCDI). Methods: A filtered solution of Japanese donor feces was endoscopically administered. The efficacy of FMT was evaluated after 8 weeks using the Mayo score, Crohn’s Disease Activity Index (CDAI), and the absence of diarrhea with stool toxin negativity in patients with active UC, CD, and rCDI, respectively. For fecal microbiota analysis, the 16S ribosomal RNA gene was sequenced, and fecal SCFA levels were measured. Results: Clinical response was achieved in 5/20 (25%), 3/4 (75%), and 4/4 (100%) patients with UC, CD, and rCDI, respectively. Clinical remission was achieved in 4/20 (20%) and 1/4 (25%) patients with UC and CD, respectively. Linear discriminant analysis illustrated that UC responders had lower counts of Clostridium cluster XIVa before FMT and higher counts after FMT. Higher Fusicatenibacter saccharivorans counts in donors were significantly correlated with 8-week clinical remission. Patients with CD exhibited lower Blautia, Dorea, and Eubacterium counts before FMT and higher Collinsella, Dorea, and Eubacterium counts after FMT, accompanied by functional profiles predictive of SCFA fermentation and elevated fecal butyrate concentrations. Patients with rCDI displayed significantly lower abundances of Clostridium clusters IV and XIVa before FMT and higher abundances after FMT accompanied by elevated fecal propionate concentrations. Conclusions: FMT exhibited various efficacy against UC, CD, and rCDI by altering the gut microbiota and SCFA production