Evolution of the Tn4371 ICE family: traR-mediated coordination of cargo gene upregulation and horizontal transfer.

ICEKKS102Tn4677 carries a bph operon for the mineralization of polychlorinated biphenyls (PCBs)/biphenyl and belongs to the Tn4371 ICE (integrative and conjugative element) family. In this study, we investigated the role of the traR gene in ICE transfer. The traR gene encodes a LysR-type transcriptional regulator, which is conserved in sequence, positioning, and directional orientation among Tn4371 family ICEs. The traR belongs to the bph operon, and its overexpression on solid medium resulted in modest upregulation of traG (threefold), marked upregulation of xis (80-fold), enhanced ICE excision and, most notably, ICE transfer frequency. We propose the evolutional roles of traR, which upon insertion to its current position, might have connected the cargo gene activation and ICE transfer. This property of ICE, i.e., undergoing transfer under environmental conditions that lead to cargo gene activation, would instantly confer fitness advantages to bacteria newly acquiring this ICE, thereby resulting in efficient dissemination of the Tn4371 family ICEs.IMPORTANCEOnly ICEKKS102Tn4677 is proven to transfer among the widely disseminating Tn4371 family integrative and conjugative elements (ICEs) from ß and γ-proteobacteria. We showed that the traR gene in ICEKKS102Tn4677, which is conserved in the ICE family with fixed location and direction, is co-transcribed with the cargo gene and activates ICE transfer. We propose that capturing of traR by an ancestral ICE to the current position established the Tn4371 family of ICEs. Our findings provide insights into the evolutionary processes that led to the widespread distribution of the Tn4371 family of ICEs across bacterial species.

A New Self-Expandable Metallic Stent with Low Axial Force and a High Axial Force Zero-Border Shows a Very Low Perforation Rate in Malignant Colorectal Obstruction: A Japanese Multicenter Prospective Study.

Background: Recently, there has been a significant increase in the utilization of self-expandable metallic stents (SEMSs) for treating malignant colorectal obstructions through colorectal stenting. The mechanical properties of SEMSs are usually considered to affect clinical outcomes of patients with malignant colorectal obstructions. Methods: This single-arm, prospective, multicenter study of SEMS with a lower axial force and high axial force zero-border included 200 patients with malignant colorectal obstruction. Technical and clinical success, stent patency, and adverse events associated with SEMS placement were evaluated. Results: One patient was excluded, and 199 patients were evaluated. The treatment intent was bridge-to-surgery in 129 and palliation in 70 patients. Technical and clinical success rates were 99.5% and 97.0%, respectively. The percentage of the ColoRectal Obstruction Scoring System scores of 3 or higher improved significantly from 19.2% before placement to 93.9% after placement. Clinical success was not achieved in five patients due to insufficient stent expansion in four patients and stent occlusion in one patient. Only one patient underwent emergency surgery for perforation of the proximal colon, far from where the stent was placed; the rescue procedure was not performed, despite no improvement in proximal dilatation due to insufficient stent expansion. Among the palliation cohort, 15 patients received chemotherapy, including molecular-targeted agents such as bevacizumab. There were no fatal cases related to stent placement. Conclusions: For management of malignant colorectal obstruction, this newly developed SEMS with low axial force and a high axial force zero-border showed high technical and clinical success rates, and an extremely low perforation rate (0.5%).

Characterization of faecal microbiota and serum inflammatory markers in dogs diagnosed with chronic enteropathy or small-cell lymphoma: a pilot study.

Dogs diagnosed with chronic enteropathy (CE) or small-cell lymphoma (SCL) exhibit marked differences in faecal microbiota and organic acid profiles compared with healthy dogs, as well as immune abnormalities in intestinal mucosal tissue. However, few studies have analysed trace organic acids, such as succinic acid, which have been suggested to be associated with IBD in humans. Therefore, in this study, we compared the faecal microbiota and organic acid profiles as well as serum inflammatory markers between dogs with disease (n = 11; 6 with CE and 5 with SCL) and healthy controls (n = 16). We also performed machine learning and correlation analysis to obtain more detailed insights into the characteristics of affected dogs. These results revealed that dogs with CE and SCL had lower levels of Erysipelotrichaceae (e.g. Turicibacter and Allobaculum), exhibited abnormalities in the succinic acid metabolism (i.e. succinic acid accumulation and decreased levels of Phascolarctobacterium as succinic acid-utilising bacteria) and increased levels of pathobiont bacteria such as Escherichia-Shigella. Additionally, the presence of Dubosiella was significantly negatively correlated with Canine Inflammatory Bowel Disease Activity Index scores. These findings are expected to aid the development of microbiome-based medications and/or supplements, although further verification is needed.

Strength dependency of frequency-magnitude distribution in earthquakes and implications for stress state criticality.

Earthquake size distribution is characterized by the "b-value" of the power law decay, which exhibits spatiotemporal variations. These variations are sometimes evident before a large earthquake. Understanding spatiotemporal variations is key to developing a model for large-earthquake generation. Previous studies have shown that changes in the b-value are caused by the tectonic stress regime. Furthermore, lab experiments have demonstrated the b-value dependency of acoustic emissions on the criticality of the failure condition. However, the factors controlling the b-values during natural seismic activity are unclear. In this study, changes in the b-value in small earthquake sequences are investigated, focusing on failure criticality. Based on our high-precision focal mechanism dataset, we conclude that the b-value decreases as it nears a critical failure condition, providing a physical explanation for the reduction in b-value before a major earthquake. Our findings elucidate fault failure models, facilitating improvement in earthquake alerts and disaster mitigation.

Significance of Adjuvant Chemotherapy for Obstructive Colorectal Cancer After Stent Placement: A Multicenter Retrospective Study.

BACKGROUND/AIM: To explore the survival benefit of adjuvant chemotherapy for obstructive colorectal cancer (OCRC) managed by self-expandable metallic stent (SEMS) placement as a bridge to surgery (BTS). PATIENTS AND METHODS: One hundred twenty-nine patients with pathological stage II/III OCRC who underwent BTS using a SEMS were included in this multicenter retrospective study. Patients were divided into the no-adjuvant chemotherapy group (No-Adj group) (n=52) and adjuvant chemotherapy group (Adj group) (n=77), and relapse-free survival (RFS) was compared. RESULTS: The No-Adj group had more fragile patient background factors, such as higher age, higher American Society of Anesthesiologists score, and lower preoperative albumin compared with the Adj group. The 3-year RFS rates for the overall cohort were significantly different between the No-Adj and Adj groups (56.4% and 78.5%, respectively; p=0.003). Significant RFS benefits of adjuvant chemotherapy were observed in both pathological stage II and III cancer. Characteristics of more advanced cancer, such as high carcinoembryonic antigen (CEA), pathological T4, and lymphovascular invasion, were associated with survival improvement by adjuvant chemotherapy. T4 and adjuvant chemotherapy were significantly associated with RFS in the multivariate Cox proportional analysis. CONCLUSION: To our knowledge, this is the first study to show a survival benefit of adjuvant chemotherapy in patients with OCRC undergoing BTS using a SEMS. Adjuvant chemotherapy is basically recommended regardless of the cancer stage and is strongly recommended with more advanced characteristics, such as high CEA, T4, and lymphovascular invasion.

Oncologic investigation of the interval from stent placement to surgery in patients with obstructive colorectal cancer.

PURPOSE: Self-expandable metallic stent (SEMS) placement is widely used as a bridge to surgery (BTS) procedure for obstructive colorectal cancer. However, evidence regarding the optimal interval between SEMS placement and elective surgery is lacking. METHODS: We retrospectively collected data from patients with BTS between January 2013 and October 2021. Inverse probability treatment-weighted propensity score analyses were used to compare short- and long-term outcomes between the short-interval (SI) and long-interval (LI) groups, using a cutoff of 20 days. RESULTS: In total, 138 patients were enrolled in this study (SI group, n = 63; LI group, n = 75). In the matched cohort, the patients' backgrounds were well balanced. The incidence of Clavien-Dindo grade ≥ II postoperative complications was not significantly different between the SI and LI groups (19.0% vs. 14.0%, P = 0.47). There were no significant differences between the SI and LI groups in the 3-year recurrence-free survival (68.0% vs. 76.4%, P = 0.73) or 3-year overall survival rates (86.0% vs. 90.6%, P = 0.72). CONCLUSIONS: A longer interval did not deteriorate the oncological outcomes. Individual perioperative management with an appropriate interval to improve the patient's condition is required to ensure safe surgery.

TrkB phosphorylation in serum extracellular vesicles correlates with cognitive function enhanced by ergothioneine in humans.

Oral administration of the food-derived antioxidant amino acid ergothioneine (ERGO) results in its efficient distribution in the brain and enhances cognitive function. However, effect of ERGO deficiency on cognitive impairment and the underlying mechanisms remain unknown. We revealed that cognitive function and hippocampal neurogenesis were lower in mice fed an ERGO-free diet than in those fed the control diet. Furthermore, ERGO supplementation to achieve the control diet ERGO levels reversed these effects and restored ERGO concentrations in the plasma and hippocampus. The ERGO-induced recovery of cognitive function and hippocampal neurogenesis was blocked by inhibiting the neurotrophic factor receptor tropomyosin receptor kinase B (TrkB), with a concomitant reduction in hippocampal phosphorylated TrkB, suggesting the involvement of TrkB in these events in mice. Phosphorylated TrkB was also detected in extracellular vesicles (EVs) derived from serum of volunteers who had been orally administered placebo or ERGO-containing tablets. Importantly, the ratio of serum EV-derived phosphorylated TrkB was significantly higher in the ERGO-treated group than in the placebo-treated group and was positively correlated with both serum ERGO concentrations and several cognitive domain scores from Cognitrax. Altogether, TrkB phosphorylation is involved in ERGO-induced cognitive enhancement in mice, and TrkB phosphorylation levels in serum EVs may quantitatively represent ERGO-induced cognitive enhancement in humans.

Three distinct metabolic phases of polychlorinated biphenyls/biphenyl degrader Acidovorax sp. KKS102 in nutrient broth.

Acidovorax sp. KKS102 is a beta-proteobacterium capable of degrading polychlorinated biphenyls (PCBs). In this study, we examined its growth in liquid nutrient broth supplemented with different carbon sources. KKS102 had at least 3 distinct metabolic phases designated as metabolic phases 1-3, with phase 2 having 2 sub-phases. For example, succinate, fumarate, and glutamate, known to repress the PCB/biphenyl catabolic operon in KKS102, were utilized in phase 1, while acetate, arabinose, and glycerol in phase 2, and glucose and mannose in phase 3. We also showed that the BphQ response regulator mediating catabolite control in KKS102, whose expression level increased moderately through the growth, plays important roles in carbon metabolism in phases 2 and 3. Our study elucidates the hierarchical growth of KKS102 in nutrient-rich media. This insight is crucial for studies exploiting microbial biodegradation capabilities and advancing studies for catabolite regulation mechanisms.

Current Status of Robotic Hepatobiliary and Pancreatic Surgery.

Laparoscopic surgery is performed worldwide and has clear economic and social benefits in terms of patient recovery time. It is used for most gastrointestinal surgical procedures, but laparoscopic surgery for more complex procedures in the esophageal, hepatobiliary, and pancreatic regions remains challenging. Minimally invasive surgery that results in accurate tumor dissection is vital in surgical oncology, and development of surgical systems and instruments plays a key role in assisting surgeons to achieve this. A notable advance in the latter half of the 1990s was the da Vinci Surgical System, which involves master-slave surgical support robots. Featuring high-resolution three-dimensional (3D) imaging with magnification capabilities and forceps with multi-joint function, anti-shake function, and motion scaling, the system compensates for the drawbacks of conventional laparoscopic surgery. It is expected to be particularly useful in the field of hepato-biliary-pancreatic surgery, which requires delicate reconstruction involving complex liver anatomy with diverse vascular and biliary systems and anastomosis of the biliary tract, pancreas, and intestines. The learning curve is said to be short, and it is hoped that robotic surgery will be standardized in the near future. There is also a need for a standardized robotic surgery training system for young surgeons that can later be adapted to a wider range of surgeries. This systematic review describes trends and future prospects for robotic surgery in the hepatobiliary-pancreatic region.

Minimally invasive surgery for esophagogastric junction cancer with Leriche's syndrome-induced ischemic enteritis in the rectum: A case report.

The incidence of esophagogastric junction cancer has been increasing, leading to growing interest in surgical treatment. Leriche syndrome, characterized by occlusion limited to the infrarenal aorta, has not been reported to be associated with ischemic enteritis, and there are no previous reports on the surgical approaches for esophagogastric junction cancer in this disease.We describe the case of a male patient in his fifties with lower abdominal pain and melena who was diagnosed with esophagogastric junction cancer, Leriche syndrome, and ischemic enteritis. Contrast-enhanced computed tomography (CT) showed a hemorrhage from the cancer, occlusion of the abdominal aorta beyond the renal artery branches, and rectal contrast deficiency. Three-dimensional (3D)-CT angiography revealed occlusion from the lumbar artery bifurcation to the distal portions of both common iliac arteries plus numerous collateral pathways, indicating a precarious rectal blood supply. Based on 3D-CT angiography, minimally invasive surgery (MIS) using laparoscopy and thoracoscopy for esophagogastric junction cancer was performed after whole-body control. The patient was discharged without any postoperative complications.Esophagogastric junction cancer with Leriche syndrome can be complicated by ischemic enteritis due to tumor bleeding and fragile collateral pathways. MIS using laparoscopy and thoracoscopy guided by 3D-CT angiography can be safely performed for this disease.

Current Status of Robotic Gastrointestinal Surgery.

Development of surgical support robots began in the 1980s as a navigation and auxiliary device for endoscopic surgery. For remote surgery on the battlefield, a master-slave-type surgical support robot was developed, in which a console surgeon operates the robot at will. The da Vinci surgical system, which currently dominates the global robotic surgery market, received United States Food and Drug Administration and regulatory approval in Japan in 2000 and 2009 respectively. The latest, fourth generation, da Vinci Xi has a good field of view via a three-dimensional monitor, highly operable forceps, a motion scale function, and a tremor-filtered articulated function. Gastroenterological tract robotic surgery is safe and minimally invasive when accessing and operating on the esophagus, stomach, colon, and rectum. The learning curve is said to be short, and robotic surgery will likely be standardized soon. Therefore, robotic surgery training should be systematized for young surgeons so that it can be further standardized and later adapted to a wider range of surgeries. This article reviews current trends and potential developments in robotic surgery.

Burkholderia cepacia-contaminated dentures possibly cause pneumonia.

We report a case in which a patient was suspected of developing pneumonia due to wearing dentures that were immersed in a storage solution contaminated with 3.0 × 108 colony-forming units (cfu)/mL of Burkholderia cepacia. It is highly possible that the contaminated denture solution entered the trachea and caused the pneumonia, possibly due to the prolonged supine positioning of the patient. We demonstrated that B. cepacia isolated from the sputum and B. cepacia isolated from the denture storage solution had the same DNA fingerprint, and that the patient recovered from pneumonia after stopping the use of dentures. These findings suggest the storage solution as the main source of infection.

Tracking supercritical geothermal fluid distribution from continuous seismic monitoring.

Continuous seismic monitoring could play a pivotal role in deep geothermal energy exploration. We monitored seismicity near geothermal production areas of the Kuju volcanic complex with a dense seismic network and automated event detection. Most events were shallow (less than 3 km below sea level) and distributed along a boundary between regions of high and low resistivity and S-wave velocity, interpreted as a lithological boundary or related fracture zone. Deeper events located on top of subvertical conductors may reflect fracturing associated with magmatic fluid intrusion. A correlation may exist between seismicity and heavy rainfall three days prior to increased pore pressure in pre-existing fractures. Our findings support the presence of supercritical geothermal fluids and demonstrate the importance of continuous seismic monitoring in supercritical geothermal energy exploration.

Peptides obtained by enzymatic decomposition of mackerel induce recovery from physical fatigue by enhancing the SIRT1-mediated antioxidant effect in the soleus muscle of mice.

Fatigue is a serious health problem, and long-term fatigue can lead to mental illnesses and accelerated aging. Oxidative stress, which causes excessive production of reactive oxygen species, is generally thought to increase during exercise and is an indicator of fatigue. Peptides obtained by enzymatic decomposition of mackerel (EMP) contain selenoneine, a strong antioxidant. Although antioxidants increase endurance, the effects of EMP on physical fatigue are unknown. The present study aimed to clarify this aspect. We investigated the effects of EMP on changes in locomotor activity, expression levels of silent mating type information regulation 2 homolog peroxisome 1 (SIRT1), proliferator-activated receptor-γ coactivator-1α (PGC1α), and antioxidative-related proteins including superoxide dismutase 1 (SOD1), SOD2, glutathione peroxidase 1, and catalase in the soleus muscle following EMP treatment before and/or after forced walking. Treatment with EMP before and after forced walking, and not only at one or another time point, improved the subsequent decrease in the locomotor activity and enhanced the levels of SIRT1, PGC1α, SOD1, and catalase expression in the soleus muscle of mice. Moreover, EX-527, a SIRT1 inhibitor, abolished these effects of EMP. Thus, we suggest that EMP combats fatigue by modulating the SIRT1/PGC1α/SOD1-catalase pathway.

Segmental or right hemi-colectomy? The optimal surgical procedure for transverse colon cancer: a propensity score-matched, multicenter, retrospective study.

PURPOSE: Extended colectomy is sometimes chosen for treatment of transverse colon cancer (TCC) because of concerns about short- and long-term outcomes. However, there is still a lack of evidence regarding the optimal surgical procedure. METHODS: We retrospectively collected and analyzed data of patients who underwent surgical treatment of pathological stage II/III TCC at four hospitals from January 2011 to June 2019. We excluded the patients with TCC located at distal transverse colon, and just evaluated and analyzed proximal and middle third TCC. Inverse probability treatment-weighted propensity score analyses was used to compare short- and long-term outcomes between patients who underwent segmental transverse colectomy (STC) and those who underwent right hemicolectomy (RHC). RESULTS: In total, 106 patients were enrolled in this study (STC group, n = 45; RHC group, n = 61). The patients' backgrounds were well balanced after matching. The incidence of major postoperative complications (Clavien-Dindo grade ≥ III) was not significantly different between the STC and RHC groups (4.5% vs. 5.6%, respectively; P = 0.53). The 3-year recurrence-free survival and overall survival rates were not significantly different between the STC and RHC groups (88.2% vs. 81.8%, P = 0.86 and 90.3% vs. 91.9%, P = 0.79, respectively). CONCLUSION: RHC has no significant benefits over STC with respect to either short- or long-term outcomes. STC with necessary lymphadenectomy could be an optimal procedure for proximal and middle TCC.

Postoperative infectious complications have a negative oncological impact in patients after stent placement with malignant large bowel obstruction.

PURPOSE: In this study, we aimed to investigate the oncological impact of postoperative infection in patients with malignant large bowel obstruction managed by self-expandable metallic stent placement as a bridge to surgery. METHODS: The cohort of this multicenter retrospective study comprised 129 patients with pathological stage II/III malignant large bowel obstruction who had undergone bridge to surgery. Patients were allocated to no-postoperative infection (n = 116) and postoperative infection groups (n = 13). RESULTS: The postoperative infection group had a significantly greater proportion of men, fewer harvested lymph nodes, and longer postoperative hospital stays than did the no-postoperative infection group. Self-expandable metallic stent-related variables, including clinical failure, were not associated with postoperative infection. Male sex and low body mass index were identified as risk factors for postoperative infection by multivariate logistic regression. Three-year relapse-free survival rates were 75.5% and 30.8% in the no-postoperative infection and postoperative infection groups, respectively; this difference is statistically significant. Male sex, postoperative infection, and T4 were identified as independent prognostic factors by multivariate Cox proportional hazard analysis. The postoperative infection group had a significantly higher total recurrence rate and shorter interval to recurrence than did the no-postoperative infection group. CONCLUSION: To the best of our knowledge, this is the first study to show that postoperative infection in bridge to surgery patients has a negative oncological impact. This finding indicates that further improvement in perioperative management of bridge to surgery patients is required to minimize postoperative infection and that patient-risk stratification and additional therapy would contribute to improving oncological outcomes.

Diverse impact of a probiotic strain, Lacticaseibacillus paracasei Shirota, on peripheral mononuclear phagocytic cells in healthy Japanese office workers: a randomized, double-blind, controlled trial.

Mononuclear phagocytic cells (MPCs) are classified into monocytes (Mos)/macrophages and dendritic cells (DCs) based on their functions. Cells of MPCs lineage act as immune modulators by affecting effector cells, such as NK cells, T cells, and B cells. This study aimed to investigate the effects of Lacticaseibacillus paracasei strain Shirota (LcS) ingestion on peripheral MPCs, particularly on their expression of functional cell-surface molecules enhanced in healthy adults. Thus, twelve healthy office workers consumed a fermented milk drink containing 1.0 × 1011 cfu of LcS (LcS-FM) or a control unfermented milk drink (CM) once a day for 6 weeks. Peripheral blood mononuclear cells (PBMCs) were prepared from blood samples, and immune cells and functional cell-surface molecules were analyzed. We observed remarkable differences in the expression of HLAABC, MICA, CD40, and GPR43 in plasmacytoid DCs (pDCs) between the LcS-FM and CM groups, whereas no difference was found in CD86 or HLADR expression. The LcS-FM group exhibited higher CD40 expression in both conventional DCs (cDCs) and Mos, especially in type 2 conventional DCs (cDC2s) and classical monocytes (cMos); higher percentages of cMos, intermediate monocytes (iMos), and nonclassical monocytes; and higher numbers of cMos and iMos in PBMCs than the CM group. LcS ingestion increased the expression of HLAABC, MICA, CD40, and GPR43 in pDCs and CD40 in cDCs and Mos, particularly cDC2s and cMos. These results suggest that LcS modulates the function of MPCs that may lead to the regulation of immune effector functions in healthy adults.

The utility of serum osteopontin levels for predicting postoperative complications after colorectal cancer surgery.

BACKGROUND/AIM: Osteopontin (OPN) is a secretory glycoprotein, which is expressed not only in osteoblasts, but immune cells including macrophages and activated T cells. Its pleiotropic immune functions, such as bone remodeling, cancer progression, immune response, and inflammation have been reported previously. However, the association between OPN and postoperative complications (POC) after colorectal cancer (CRC) surgery has not been studied, so far. METHODS: Peripheral blood samples were collected before (pre) and immediately after surgery (post), and on postoperative days (POD) 1, 3, 5, and 7. Serum OPN levels were measured by ELISA. In total, 78 patients who underwent elective CRC surgery were divided into the No-POC (n = 54) and POC (n = 24) groups. RESULTS: The POC group had significantly higher OPN levels than the No-POC group throughout the postoperative observation period. The maximum OPN levels from pre- to postsurgical samples showed the best predictive potential for POCs (cut off: 20.75 ng/mL, area under the curve: 0.724) and were correlated with length of postoperative stays. OPN values were significantly correlated with C-reactive protein on POD3 and were identified as an independent predictive marker for POCs (odds ratio: 3.88, 95% CI: 1.175-12.798, P = 0.026). The severity of POCs was reflected in increased OPN levels. CONCLUSION: Increased postoperative OPN was associated with increased postoperative inflammatory host responses and POC after CRC surgery. Serum OPN level may be a useful biomarker for early prediction of POC and it may provide additional information for treatment decisions to prevent POC.

Elevated serum creatine kinase levels due to osimertinib: A case report and review of the literature.

INTRODUCTION: Osimertinib is a tyrosine kinase inhibitor that targets the epidermal growth factor receptor. Elevated serum creatine kinase level is an uncommon adverse event associated with osimertinib treatment for lung cancer. CASE REPORT: We report a previously healthy 56-year-old woman who developed elevated serum creatine kinase levels during osimertinib monotherapy for epidermal growth factor receptor mutation-positive lung adenocarcinoma. MANAGEMENT & OUTCOME: During treatment, she experienced leg cramps and her serum creatine kinase levels increased, peaking at 989 U/l. Further investigation revealed no evidence of cardiotoxicity or myositis; thus, osimertinib-induced myopathy was assumed to be the cause of her elevated serum creatine kinase levels. We successfully managed both lung cancer and osimertinib-induced myopathy using 1-week pauses of osimertinib therapy without dose reduction. DISCUSSION: Short-term suspension of osimertinib without dose reduction may be a reasonable option for osimertinib-induced myopathy.

Stool preparation under anaerobic conditions contributes to retention of obligate anaerobes: potential improvement for fecal microbiota transplantation.

BACKGROUND: Fecal microbiota transplantation (FMT) in patients with ulcerative colitis has shown variable efficacy depending on the protocol used. A previous randomized controlled trial reported that anaerobic preparation of donor stool contributes to improved efficacy. Despite the suggestion that viable obligate anaerobes would be decreased through aerobic handling, there have been only a limited number of reports on how these aerobic or anaerobic procedures affect the composition of viable microbiota in the fecal slurries used for FMT. METHODS: We adopted 16S and 23S rRNA-targeted reverse transcription-quantitative polymerase chain reaction to quantify viable bacteria in fecal slurries. This study utilized specific primers designed to detect obligate anaerobes (including Clostridium coccoides group, C. leptum subgroup, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, and Prevotella) and facultative anaerobes (including total lactobacilli, Enterobacteriaceae, Enterococcus, Streptococcus, and Staphylococcus). We then calculated the ratio change (RC) between before and after mixing, and compared the resulting values between anaerobic-prep and aerobic-prep in samples fixed immediately after blending (RCAn0 vs. RCAe0) and in samples maintained (under anaerobic or aerobic conditions) for 1 h after blending (RCAn1 vs. RCAe1). RESULTS: For most obligate anaerobes, the median RC tended to be less than 1, indicating that the number of obligate anaerobes was decreased by the blending procedure. However, in samples maintained for 1 h after blending, anaerobic-prep counteracted the decrease otherwise seen for the C. coccoides group and B. fragilis groups (P < 0.01 for both). The C. leptum subgroup also tended to show higher RC by anaerobic-prep than by aerobic-prep, although this effect was not statistically significant. Among facultative anaerobes, Enterobacteriaceae, Enterococcus, and Staphylococcus showed median RC values of more than 1, indicating that these organisms survived and even grew after mixing. Moreover, oxygen exposure had no significant influence on the survival of the facultative anaerobes. CONCLUSIONS: The conditions under which the blending procedure was performed affected the proportion of live anaerobes in fecal slurries. The obligate anaerobes tended to be decreased by blending processes, but anaerobic-prep significantly mitigated this effect. Anaerobic-prep may improve the efficacy of FMT by permitting the efficient transfer of obligate anaerobes to patients with ulcerative colitis.