Genomic analysis of inter-hospital transmission of vancomycin-resistant Enterococcus faecium sequence type 80 isolated during an outbreak in Hiroshima, Japan.

Outbreaks caused by vancomycin-resistant enterococci that transcend jurisdictional boundaries are occurring worldwide. This study focused on a vancomycin-resistant enterococcus outbreak that occurred between 2018 and 2021 across two cities in Hiroshima, Japan. The study involved genetic and phylogenetic analyses using whole-genome sequencing of 103 isolates of vancomycin-resistant enterococci to identify the source and transmission routes of the outbreak. Phylogenetic analysis was performed using core genome multilocus sequence typing and core single-nucleotide polymorphisms; infection routes between hospitals were inferred using BadTrIP. The outbreak was caused by Enterococcus faecium sequence type (ST) 80 carrying the vanA plasmid, which was derived from strain A10290 isolated in India. Of the 103 isolates, 93 were E. faecium ST80 transmitted across hospitals. The circular vanA plasmid of the Hiroshima isolates was similar to the vanA plasmid of strain A10290 and transferred from E. faecium ST80 to other STs of E. faecium and other Enterococcus species by conjugation. The inferred transmission routes across hospitals suggest the existence of a central hospital serving as a hub, propagating vancomycin-resistant enterococci to multiple hospitals. Our study highlights the importance of early intervention at the key central hospital to prevent the spread of the infection to small medical facilities, such as nursing homes, with limited medical resources and a high number of vulnerable individuals.

Recombinant bone matrix maintains the graft space, induces vascularized bone regeneration and preserves canine tooth extraction socket structure.

AIM: Recombinant bone matrix (RBM) is a newly conceived and engineered porous bone graft granule of average size 600 µm composed of purified recombinant collagen peptide. We sought to examine the behaviour with time of RBM that was grafted in the canine tooth extraction socket. MATERIALS AND METHODS: The canine tooth extraction socket of the hemisectioned mandibular third premolar distal root was grafted with RBM granules, whereas the opposite side extraction socket served as non-grafted control. The mandibular samples were harvested at 1, 3 and 6 months of healing and subjected to micro-CT imaging and decalcified paraffin-embedded histology. Separately, the effect of RBM was compared with that of deproteinized cancellous bovine bone (DCBB) and bovine atelocollagen plug (BACP) in the canine tooth extraction model at 3 months of healing. RESULTS: RBM maintained the grafted space in the socket and the gingival connective tissue until new bone was formed within its porous space. The regenerated bone was highly vascularized and continued to mature, while RBM was completely bioresorbed by 6 months. The buccal and lingual alveolar ridge heights of the RBM-grafted extraction socket was better preserved than those of non-grafted control sockets. The degree of socket preservation by RBM was equivalent to that by DCBB, although their healing mechanisms were different. CONCLUSIONS: This study demonstrated that RBM induced controlled active bone regeneration and preserved the extraction socket structure in a canine model. Bioresorbable RBM engineered without animal or human source materials presents a novel bone graft category with robust bone regenerative property.

A novel animal model of colonic stenosis to aid the development of new stents for colon strictures.

BACKGROUND: The incidence of colonic stenosis, primarily caused by colon cancer and Crohn's disease, is increasing each year. The development of safer stents for colonic stenosis is required because perforation associated with cancer stent placement worsens the prognosis and stent placement for anastomotic stenosis due to Crohn's disease or colectomy is not first choice due to the high migration rate. The wall of the large intestine where the stent is inserted receives the complex forces from the peristaltic movement of the large intestine and stool in addition to the reaction tension of the stent, causing perforation and migration. Animal models may help develop new and safe stents, but no animal model closely reproduces the condition of human colonic stenosis. Herein, we present a novel animal model of colonic stenosis, which closely replicates the human colonic size. METHODS: The artificial colonic stenosis model was developed by wrapping the porcine colon with a silicone sheet after laparotomy. The usefulness of the model was evaluated by investigating the availability of endoscopic stent placement, morphological maintenance of colonic stenosis, adverse effects on pigs, and modeling time. The first three and the last three modeling times were analyzed using Student's t-test. RESULTS: Endoscopic stent placement was performed in all cases without intraoperative complications. There were no postoperative model complications or deaths. Adhesions to the surrounding tissue in the abdominal cavity of the artificial colon stenosis were slight. The morphology of the isolated artificial stenoses was completely maintained, and no necrosis or perforation was observed. CONCLUSIONS: We developed a novel and feasible animal model of colonic stenosis using pigs. We believe that this animal model will be useful for developing a safer stent for obstruction caused by benign diseases and colon cancer.

Early response in phosphorylation of ribosomal protein S6 is associated with sensitivity to trametinib in colorectal cancer cells.

Mutations in RAS or BRAF are associated with poor prognosis and resistance to epidermal growth factor receptor (EGFR)-targeted therapy in colorectal cancer (CRC). Despite their common ability to activate downstream genes such as MEK and ERK, the therapeutic benefit of MEK inhibitors for patients with RAS/BRAF mutant CRC is limited, highlighting the need for biomarkers to predict the efficacy of MEK inhibition. Previously, we reported that a change in phosphorylation of ribosomal protein S6 (pS6) after MEK inhibition was significantly associated with sensitivity to MEK inhibition in gastric cancer cells. Here, we investigated the value of the response in pS6 for predicting the efficacy of trametinib, a MEK inhibitor, in patients with RAS/BRAF mutant CRC using patient-derived CRC organoids. We found that a subset of CRC cell lines and organoids were sensitive to trametinib. The change in phosphorylated ERK, a downstream molecule of the RAS/RAF/MEK pathway, was not significantly associated with trametinib sensitivity. On the other hand, only those with sensitivity showed a reduction of pS6 levels in response to trametinib. The change in pS6 after trametinib treatment was detectable by Western blotting, immunohistochemistry or immunocytochemistry. We also demonstrated an impact of MEK inhibition on pS6 in vivo using a xenograft model. Our data suggest that, in combination with patient-derived organoids, immunostaining-based detection of pS6 could be useful for prediction of trametinib sensitivity.

Appropriate mesh size in the totally extraperitoneal repair of groin hernias based on the intraoperative measurement of the myopectineal orifice.

BACKGROUND: Insufficient coverage of the area of a possible groin hernia is an important risk factor in hernia recurrence. To prevent recurrence, it is important to use the appropriate mesh size based on the size of the myopectineal orifice (MPO), which is the weak area of the abdominal wall where inguinal hernias occur. We aimed to estimate the appropriate mesh size for groin hernias by investigating MPO size. METHODS: Four hundred and six patients underwent groin hernia repair using a totally extraperitoneal (TEP) approach at the Zeze Hospital between July 2009 and December 2017. We investigated patients' backgrounds, MPO components dimensions, and hernia recurrence, and evaluated the appropriate mesh size. RESULTS: The 359 male and 47 female patients had an average age of 63 ± 15 years. In 171, 147, and 88 cases, hernias were localized to the right, left, and bilaterally, respectively. The number of lateral, medial, femoral, and combined hernias was 317, 124, 11, and 42, respectively. The 95th percentile for the horizontal and vertical lengths in cases of hernia orifice ≥ 3 cm were 9.6 cm and 7.0 cm, respectively, while it was 9.2 cm and 6.4 cm in cases of hernia orifice < 3 cm. We added 2 cm and 3 cm to the 95th percentile for the length and width of the MPO, resulting in 13.2 × 10.4 cm and 15.6 × 13.0 cm in cases with hernia orifice < 3 cm and ≥ 3 cm, respectively. Relapse after TEP occurred in 1 patient (0.2%). CONCLUSION: The appropriate mesh size for TEP repair, derived from intraoperative MPO measurements, was estimated as 13.2 × 10.4 cm and 15.6 × 13.0 cm when the hernia orifice was < 3 cm and ≥ 3 cm, respectively. Using appropriate mesh sizes based on MPO measurement may reduce groin hernia recurrence after TEP.

Role of increased vascular permeability in chemotherapy-induced alopecia: In vivo imaging of the hair follicular microenvironment in mice.

Chemotherapy-induced alopecia is one of the most difficult adverse events of cancer treatment for patients. However, it is still unknown why anticancer drugs cause hair loss. We aimed to clarify the mechanism of chemotherapy-induced alopecia in mice using an in vivo imaging technique with a two-photon microscope, which enables observation of the deep reaction in the living body in real time. In this study, ICR mice were injected intraperitoneally with cyclophosphamide (120 µg/g). Changes in the hair bulb morphology, subcutaneous vessel permeability, and vessel density were evaluated by two-photon microscopy and conventional methods. In order to determine whether there is a causal relationship between vascular permeability and hair loss, we combined cyclophosphamide (50 µg/g) with subcutaneous histamine. Using two­photon microscopy and conventional examination, we confirmed that the hair bulbs became smaller, blood vessels around the hair follicle decreased, and vascular permeability increased at 24 hours after cyclophosphamide injection [corrected]. Apoptosis occurred in vascular endothelial cells around the hair follicle. Additionally, hair loss was exacerbated by temporarily enhancing vascular permeability with histamine. In conclusion, cyclophosphamide caused a decrease in vascular density and an increase in vascular permeability, therefore increased vascular permeability might be one of the causes of chemotherapy-induced alopecia.

Intraperitoneal Phototherapy Suppresses Inflammatory Reactions in a Surgical Model of Peritonitis.

BACKGROUND: Standard treatment for diffuse peritonitis due to colorectal perforation may be insufficient to suppress inflammatory reaction in sepsis. Thus, developing new treatments is important. This study aimed to examine whether intraperitoneal irradiation by artificial sunlight suppresses inflammatory reaction in a lipopolysaccharide (LPS)-induced peritonitis model after surgical treatments. MATERIALS AND METHODS: Mice were divided into naive, nontreatment (NT), and phototherapy (PT) groups. In the latter two groups, LPS was intraperitoneally administered to induce peritonitis and removed by intraperitoneal lavage after laparotomy. The PT group was irradiated with artificial sunlight intraperitoneally. We evaluated the local and systemic inflammatory reactions. Murine macrophages were irradiated with artificial sunlight after stimulation by LPS, and cell viability and expression of tumor necrotizing factor-α (TNF-α) were evaluated. RESULTS: As a local inflammatory reaction, the whole cell count, the expression of interleukin-6 and TNF-α in the intra-abdominal fluid, and the peritoneal thickness were significantly lower in the PT group than in the NT group. As a systematic inflammatory reaction, the expression of serum TNF-α, granulocyte macrophage colony-stimulating factor, monocyte chemotactic protein-1, macrophage inflammatory protein (MIP)-1α, and MIP-1ß were significantly lower in the PT group than in the NT group. Irradiation by artificial sunlight suppressed the expression of TNF-α in murine macrophages without affecting cell viability. CONCLUSIONS: Intraperitoneal irradiation by artificial sunlight could suppress local and systemic inflammatory reactions in the LPS-induced peritonitis murine model. These effects may be associated with macrophage immune responses.

Gastric Carcinoma as Second Malignant Neoplasm in a Survivor From High-risk Neuroblastoma.

Childhood cancer survivors (CCSs) from high-grade malignancies, such as high-risk neuroblastoma, have been increased, and second malignant neoplasm, becomes a serious problem for CCSs. However, detailed reports about rare types of second cancer such as gastric cancer remain limited. We herein reported a female patient who developed diffuse type gastric carcinoma after 21 years from completion of treatment to high-risk neuroblastoma. We reviewed the previous cohort studies for second gastrointestinal cancer in CCSs and the case reports with second gastric carcinoma for CCSs. We presumed second gastric cancer was refractory for CCSs as well as for adult cancer survivors.

Epidemiological Aspects of Escherichia albertii Outbreaks in Japan and Genetic Characteristics of the Causative Pathogen.

Zoonotic pathogen Escherichia albertii has been identified as the cause of several human disease outbreaks; however, factors such as the general symptoms and incubation period of E. albertii infection have yet to be defined. Therefore, we aimed to determine the unique aspects of E. albertii outbreaks in Japan and to examine the genetic characteristics of the causative pathogen. We studied all known E. albertii outbreaks that occurred in Japan up until 2015, which consisted of five confirmed outbreaks and one putative outbreak (Outbreaks 1-6). Outbreaks were re-examined based on personal communications between researchers in prefectural and municipal public health institutes, and through examination of any published study conducted at the time. Draft genome sequences of outbreak-associated E. albertii isolates were also generated. The most common symptom displayed by patients across the six episodes was watery diarrhea (>80%), followed by abdominal pain (50-84%) and fever (37.0-39.5°C) (26-44%). The estimated average incubation period of E. albertii infection was 12-24 h. We assumed that most of the outbreaks were foodborne or waterborne, with restaurant foods, restaurant water, and boxed lunches being the suspected transmission vehicles. Three of the six outbreak-associated E. albertii isolates possessed intact ETT2 regions, while the remaining isolates contained disrupted ETT2-encoding genes. Virulence gene screening revealed that more than half (44/70) of the tested genes were present in all 5 strains examined, and that each of the strains contained more than 1 gene from 14 out of the 21 groups of virulence genes examined in this study. The five E. albertii strains were classified into four of the five known phylogroups. Therefore, we determined that multiple E. albertii genotypes in Japan have the potential to cause outbreaks of diarrhea, abdominal pain, and/or fever following infection of a human host.

The utility of DHL-HisZnNa, a novel antioxidant, against anticancer agent-induced alopecia in breast cancer patients: a multicenter phase II clinical trial.

PURPOSE: Chemotherapy-induced alopecia (CIA) is a distressing adverse effect of anticancer drugs; however, there are currently no mechanisms to completely prevent CIA. In this study, we performed a clinical trial to examine whether sodium N-(dihydrolipoyl)-l-histidinate zinc complex (DHL-HisZnNa), an alpha-lipoic acid derivative, prevents CIA in patients with breast cancer. METHODS: Between July 2014 and May 2015, we performed a multi-center, single arm, clinical trial involving 103 breast cancer patients who received adjuvant chemotherapy at three medical institutions in Japan. During chemotherapy, a lotion containing 1% DHL-HisZnNa was applied daily to the patients' scalps. The primary endpoint was the incidence of grade 2 alopecia; the secondary endpoints were the duration of grade 2 alopecia, alopecia-related symptoms, and drug-related adverse events. Alopecia was evaluated by three independent reviewers using head photographs taken from four angles. RESULTS: Safety analysis was performed for 101 patients who started the protocol therapy. After excluding one patient who experienced disease progression during treatment, 100 patients who received at least two courses of chemotherapy underwent efficacy analysis. All original 101 patients developed grade 2 alopecia, the median durations of which were 119 days (112-133 days) and 203 days (196-212 days) in the groups treated with four and eight courses of chemotherapy, respectively. Mild or moderate adverse events potentially related to DHL-HisZnNa were observed in 11 patients. Alopecia-related symptoms were observed in 53 patients (52%). CONCLUSIONS: The application of 1% DHL-HisZnNa to the scalp did not prevent CIA. However, this drug may promote recovery from CIA. TRIAL REGISTRATION NUMBER: UMIN000014840.

Legionella pneumophila and Other Legionella Species Isolated from Legionellosis Patients in Japan between 2008 and 2016.

The Legionella Reference Center in Japan collected 427 Legionella clinical isolates between 2008 and 2016, including 7 representative isolates from corresponding outbreaks. The collection included 419 Legionella pneumophila isolates, of which 372 belonged to serogroup 1 (SG1) (87%) and the others belonged to SG2 to SG15 except for SG7 and SG11, and 8 isolates of other Legionella species (Legionella bozemanae, Legionella dumoffii, Legionella feeleii, Legionella longbeachae, Legionella londiniensis, and Legionella rubrilucens). L. pneumophila isolates were genotyped by sequence-based typing (SBT) and represented 187 sequence types (STs), of which 126 occurred in a single isolate (index of discrimination of 0.984). These STs were analyzed using minimum spanning tree analysis, resulting in the formation of 18 groups. The pattern of overall ST distribution among L. pneumophila isolates was diverse. In particular, some STs were frequently isolated and were suggested to be related to the infection sources. The major STs were ST23 (35 isolates), ST120 (20 isolates), and ST138 (16 isolates). ST23 was the most prevalent and most causative ST for outbreaks in Japan and Europe. ST138 has been observed only in Japan, where it has caused small-scale outbreaks; 81% of those strains (13 isolates) were suspected or confirmed to infect humans through bath water sources. On the other hand, 11 ST23 strains (31%) and 5 ST120 strains (25%) were suspected or confirmed to infect humans through bath water. These findings suggest that some ST strains frequently cause legionellosis in Japan and are found under different environmental conditions.IMPORTANCELegionella pneumophila serogroup 1 (SG1) is the most frequent cause of legionellosis. Our previous genetic analysis indicated that SG1 environmental isolates represented 8 major clonal complexes, consisting of 3 B groups, 2 C groups, and 3 S groups, which included major environmental isolates derived from bath water, cooling towers, and soil and puddles, respectively. Here, we surveyed clinical isolates collected from patients with legionellosis in Japan between 2008 and 2016. Most strains belonging to the B group were isolated from patients for whom bath water was the suspected or confirmed source of infection. Among the isolates derived from patients whose suspected infection source was soil or dust, most belonged to the S1 group and none belonged to the B or C groups. Additionally, the U group was discovered as a new group, which mainly included clinical isolates with unknown infection sources.

Anti-proliferation effect of blue light-emitting diodes against antibiotic-resistant Helicobacter pylori.

BACKGROUND AND AIM: Infection by Helicobacter pylori is implicated in a wide range of upper gastrointestinal diseases. Owing to the rapid emergence of antibiotic-resistant strains of H. pylori, the development of novel treatment modalities for antibiotic-resistant H. pylori infection is a key priority. Blue light-emitting diodes (LED) may represent a unique option owing to their antimicrobial effect. In this study, we aimed to evaluate the anti-proliferative effect of blue LED against antibiotic-resistant H. pylori. METHODS: Ten antibiotic-resistant strains and one sensitive H. pylori strain were used in this study. After irradiation by blue LED along time course, the viability of H. pylori was evaluated by enumerating colony forming units. Morphological changes in H. pylori were observed using a scanning electron microscope. Reductase activity was measured as an indicator of bacterial cellular activity. Total reactive oxygen species was monitored using fluorescence intensity and fluorescence microscope imaging. RESULTS: After irradiation by blue LED, the numbers of H. pylori in all the strains were significantly reduced compared with control group. The H. pylori exhibited a short rod-shaped morphology after irradiation; no such change was observed in H. pylori not exposed to blue LED. Re-irradiation of surviving strain after the initial irradiation also exhibited the same anti-proliferation effect. After blue LED irradiation, bacterial cellular activity was lower, and total reactive oxygen species production was significantly higher in blue LED group, compared with that in control. CONCLUSIONS: Blue LED could be a new treatment to eradicate infection with antibiotic-resistant H. pylori.

Novel Feline Leukemia Virus Interference Group Based on the env Gene.

Feline leukemia virus (FeLV) subgroups have emerged in infected cats via the mutation or recombination of the env gene of subgroup A FeLV (FeLV-A), the primary virus. We report the isolation and characterization of a novel env gene, TG35-2, and report that the TG35-2 pseudotype can be categorized as a novel FeLV subgroup. The TG35-2 envelope protein displays strong sequence identity to FeLV-A Env, suggesting that selection pressure in cats causes novel FeLV subgroups to emerge.

The alpha-lipoic acid derivative DHLHZn: a new therapeutic agent for acute lung injury in vivo.

OBJECTIVE AND DESIGN: An animal experiment was performed to demonstrate the anti-inflammatory effects of an alpha-lipoic acid (ALA) derivative, dihydrolipoyl histidinate zinc complex (DHLHZn) for acute lung injury (ALI) and to investigate the mechanism of action. MATERIAL: Rats were randomly divided into three experimental groups: control group (n = 17), DHLHZn(-) group (n = 11, ALI model rats), and DHLHZn(+) group (n = 12, ALI model rats treated by DHLHZn). TREATMENT: Lipopolysaccharides (LPS, 10 mg/kg) were administered intratracheally in the DHLHZn(-) group and the DHLHZn(+) group. For the DHLHZn(+) group, DHLHZn (100 mg/kg) was administered intraperitoneally 2 h prior to LPS administration. METHODS: Four hours after LPS administration, bronchoalveolar lavage fluid (BALF) and lung tissue were collected. The findings were analyzed using the Mann-Whitney U test. RESULTS: Total number of cells, number of neutrophils and lymphocytes, levels of various inflammatory cytokines, and NF-kB p65 concentration of BALF were significantly lower in the DHLHZn(+) group than in the DHLHZn(-) group (p < 0.05). ALI pathology scores were significantly lower in the DHLHZn(+) group than in the DHLHZn(-) group (p < 0.001). CONCLUSIONS: Anti-inflammatory effects of DHLHZn for ALI were demonstrated by BALF and histopathological findings. The mechanism of action of DHLHZn was considered to be via inhibition of the NF-kB signaling pathway. DHLHZn is thus suggested to be a new prophylactic agent for ALI.

Refrex-1, a soluble restriction factor against feline endogenous and exogenous retroviruses.

The host defense against viral infection is acquired during the coevolution or symbiosis of the host and pathogen. Several cellular factors that restrict retroviral infection have been identified in the hosts. Feline leukemia virus (FeLV) is a gammaretrovirus that is classified into several receptor interference groups, including a novel FeLV-subgroup D (FeLV-D) that we recently identified. FeLV-D is generated by transduction of the env gene of feline endogenous gammaretrovirus of the domestic cat (ERV-DCs) into FeLV. Some ERV-DCs are replication competent viruses which are present and hereditary in cats. We report here the determination of new viral receptor interference groups and the discovery of a soluble antiretroviral factor, termed Refrex-1. Detailed analysis of FeLV-D strains and ERV-DCs showed two receptor interference groups that are distinct from other FeLV subgroups, and Refrex-1 specifically inhibited one of them. Refrex-1 is characterized as a truncated envelope protein of ERV-DC and includes the N-terminal region of surface unit, which is a putative receptor-binding domain, but lacks the transmembrane region. Refrex-1 is efficiently secreted from the cells and appears to cause receptor interference extracellularly. Two variants of Refrex-1 encoded by provirus loci, ERV-DC7 and DC16, are expressed in a broad range of feline tissues. The host retains Refrex-1 as an antiretroviral factor, which may potentially prevent reemergence of the ERVs and the emergence of novel ERV-related viruses in cats. Refrex-1 may have been acquired during endogenization of ERV-DCs and may play an important role in retroviral restriction and antiviral defense in cats.

Phototherapy with artificial light suppresses dextran sulfate sodium-induced colitis in a mouse model.

BACKGROUND AND AIM: Medical treatment for inflammatory bowel disease (IBD) requires chronic administration and causes side effects. Recently, anti-inflammatory effects of phototherapy were reported in animal models. The present study evaluated whether phototherapy improves dextran sulfate sodium (DSS)-induced colitis in a mouse model of IBD. METHODS: Mice were divided into four equal groups: Control, DSS, DSS + light low (LL), and DSS + light high (LH) groups. Normal fluorescent light intensity in the Control and DSS groups was 200 lux. Artificial light intensities were as follows: DSS + LL group, 1000 lux; DSS + LH group, 2500 lux. After administering phototherapy for 7 days, we evaluated disease activity index (DAI), histological score, colon length/weight, serum 1,25-dihydroxyvitamin D(3) level, and serum and colonic cytokines in the mice. RESULTS: DAI and histological scores were significantly lower in the DSS + LL group than in the DSS group (both, P < 0.05). Colon length and weight were significantly higher in the DSS + LL group than in the DSS group (both, P < 0.05). Serum interleukin (IL)-6, TNF-α, and IL-17 in the DSS + LL group were significantly lower, and serum and colonic IL-10 were significantly higher in the DSS + LL group than in the DSS group (all, P < 0.05). Serum 1,25-dihydroxyvitamin D(3) levels in the DSS + LH group were significantly increased compared with those in the DSS + LL and DSS groups. CONCLUSION: Artificial light phototherapy suppressed DSS-induced colitis in mice by suppression of pro-inflammatory cytokines and promotion of anti-inflammatory cytokines.

A comparison of laparoscopic and open surgery following pre-operative chemoradiation therapy for locally advanced lower rectal cancer.

OBJECTIVE: Although pre-operative chemoradiation therapy for advanced lower rectal cancer is a controversial treatment modality, it is increasingly used in combination with surgery. Few studies have considered the combination of chemoradiation therapy followed by laparoscopic surgery for locally advanced lower rectal cancer; therefore, this study aimed to assess the usefulness of this therapeutic combination. METHODS: We retrospectively reviewed the medical records of patients with locally advanced lower rectal cancer treated by pre-operative chemoradiation therapy and surgery from February 2002 to November 2012 at Oita University. We divided patients into an open surgery group and a laparoscopic surgery group and evaluated various parameters by univariate and multivariate analyses. RESULTS: In total, 33 patients were enrolled (open surgery group, n = 14; laparoscopic surgery group, n = 19). Univariate analysis revealed that compared with the open surgery group, operative time was significantly longer, whereas intra--operative blood loss and intra-operative blood transfusion requirements were significantly less in the laparoscopic surgery group. There were no significant differences in post-operative complication and recurrence rates between the two groups. According to multivariate analysis, operative time and intra-operative blood loss were significant predictors of outcome in the laparoscopic surgery group. CONCLUSIONS: This study suggests that laparoscopic surgery after chemoradiation therapy for locally advanced lower rectal cancer is a safe procedure. Further prospective investigation of the long-term oncological outcomes of laparoscopic surgery after chemoradiation therapy for locally advanced lower rectal cancer is required to confirm the advantages of laparoscopic surgery over open surgery.

Bolus injection of newly synthesized vitamin E derivative ETS-GS for the treatment of acute severe ulcerative colitis in a mouse model. New vitamin E derivative for acute severe UC.

PURPOSE: Vitamin E with its antioxidant action has therapeutic effects on ulcerative colitis (UC), but use of vitamin E is limited because of its insolubility in water. We developed ETS-GS (γ-L-glutamyl-S-[2-[[[3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltri-decyl)-2 H-1-benzopyran-6-yl]oxy]carbonyl]-3-oxo-3-[(2-sulfoethyl)amino]propyl]-L-cysteinylglycine sodium salt), a newly synthesized soluble vitamin E derivative with strong antioxidant action. We evaluated the therapeutic effects of bolus injection of ETS-GS on acute severe UC in a mouse model. METHODS: An animal model of acute severe UC was induced by feeding mice 5 % dextran sulfate sodium (DSS) for 5 days, followed by 1 % DSS on days 5-8, the experimental period. ETS-GS or saline was administered by subcutaneous bolus injection during the experimental period. We examined disease activity index (DAI) score, histological score, colon length, colon weight, and serum cytokines in the mice. RESULTS: The following results at day 8 in the DSS + ETS-GS group were significantly lower than those in the DSS + Saline group: DAI score, 2.6 ± 0.6 vs. 3.1 ± 0.5; histological score, 2.1 ± 1.0 vs. 3.1 ± 0.8; serum interleukin (IL)-6, 15 ± 9.4 vs. 39 ± 23 pg/ml; and keratinocyte-derived chemokine (KC), 122 ± 61 vs. 228 ± 66 pg/ml (P < 0.05). Colon length, colon weight, and serum IL-10 in the DSS + ETS-GS group were significantly higher than those in the DSS + Saline group (88 ± 12 vs. 75 ± 5.7 mm, 0.48 ± 0.09 vs. 0.38 ± 0.05 g, and 55 ± 18 vs. 31 ± 10 pg/ml, respectively; P < 0.05). CONCLUSIONS: Bolus injection of ETS-GS may be one therapeutic modality for acute severe UC. Its effects are associated with suppression of serum IL-6 and serum KC and promotion of serum IL-10.

Collagen type I-based recombinant peptide promotes bone regeneration in rat critical-size calvarial defects by enhancing osteoclast activity at late stages of healing.

Introduction: We recently demonstrated the bone-forming potential of medium-cross-linked recombinant collagen peptide (mRCP) in animal models of bone defects. However, these studies were limited to a 4-week observation period; therefore, in the present study, we aimed to further evaluate mRCP as a suitable bone graft material for the alveolar cleft by analyzing its bone-forming potential, osteogenic-inducing ability, and biodegradation over an extended period of 12 weeks, using a rat critical-size calvarial defect model. Methods: Using Sprague-Dawley rats, we created critical-size calvarial defects through a surgical procedure. The defects were then filled with 3 mg of mRCP (mRCP group) or 18 mg of Cytrans® (CA) granules, which has a carbonate apatite-based composition resembling natural bone, was used as a reference material (CA group). For negative control, the defects were left untreated. Bone volume, total bone volume (bone volume including CA granules), and bone mineral density (BMD) in the defect were assessed using micro-computed tomography (µ-CT) at 0, 4, 8, and 12 weeks after implantation. Using histomorphometric analyses of hematoxylin and eosin (H&E)-stained sections, we measured the amount of newly formed bone and total newly formed bone (new bone including CA granules) in the entire defect site, as well as the amount of newly formed bone in the central side, two peripheral sides (left and right), periosteal (top) side, and dura mater (bottom) side. In addition, we measured the amount of residual bone graft material in the defect. Osteoclasts and osteoblasts in the newly formed bone were detected using tartrate-resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) staining, respectively. Results: Bone volume in the mRCP group increased over time and was significantly larger at 8 and 12 weeks after surgery than at 4 weeks. The bone volume in the mRCP group was greater than that of the CA and control groups at 4, 8, and 12 weeks after implantation, and while the total bone volume was greater in the CA group after 4 and 8 weeks, the mRCP group had comparable levels of total bone volume to that of the CA group at 12 weeks after implantation. The BMD of the mRCP group reached similar levels to native calvaria bone at the same time point. H&E-stained sections revealed a larger amount of newly formed bone 12 weeks after implantation in the mRCP group compared to that of the CA and control groups. The total newly formed bone at 12 weeks after implantation was on par with that in the CA group. Furthermore, at the defect site, the area of newly formed bone was larger on the peripheral and dura mater sides. Notably, the number of osteoclasts in the mRCP group was higher than in the CA and control groups and peaked 8 weeks after implantation, which coincided with the timing of the greatest resorption of mRCP. Although the ALP-positive area was greater in the mRCP group compared to other groups, we did not detect any significant changes in the number of osteoblasts over time. Conclusion: This study demonstrated the bone-forming potential of mRCP over an extended period of 12 weeks, suggesting that mRCP sufficiently resists resorption to promote bone formation through induction of osteoclast activation in the late stages of the healing period.

Appropriate pore size for bone formation potential of porous collagen type I-based recombinant peptide.

Introduction: In this study, we developed porous medium cross-linked recombinant collagen peptide (mRCP) with two different ranges of interconnected pore sizes, Small-mRCP (S-mRCP) with a range of 100-300 µm and Large-mRCP (L-mRCP) with a range of 200-500 µm, to compare the effect of pore size on bone regeneration in a calvarial bone defect. Methods: Calvarial bone defects were created in Sprague-Dawley rats through a surgical procedure. The rats were divided into 2 groups: S-mRCP implanted group and L-mRCP implanted group. The newly formed bone volume and bone mineral density (BMD) was evaluated by micro-computed tomography (micro-CT) immediately after implantation and at 1, 2, 3, and 4 weeks after implantation. In addition, histological analyses were carried out with hematoxylin and eosin (H&E) staining at 4 weeks after implantation to measure the newly formed bone area between each group in the entire defect, as well as the central side, the two peripheral sides (right and left), the periosteal (top) side and the dura matter (bottom) side of the defect. Results: Micro-CT analysis showed no significant differences in the amount of bone volume between the S-mRCP and L-mRCP implanted groups at 1, 2, 3 and 4 weeks after implantation. BMD was equivalent to that of the adjacent native calvaria bone at 4 weeks after implantation. H&E images showed that the newly formed bone area in the entire defect was significantly larger in the S-mRCP implanted group than in the L-mRCP implanted group. Furthermore, the amount of newly formed bone area in all sides of the defect was significantly more in the S-mRCP implanted group than in the L-mRCP implanted group. Conclusion: These results indicate that the smaller pore size range of 100-300 µm is appropriate for mRCP in bone regeneration.