Risk factors and treatment strategies for cholecystitis after metallic stent placement for malignant biliary obstruction: a multicenter retrospective study.

BACKGROUND AND AIMS: Cholecystitis can occur after self-expandable metallic stent (SEMS) placement for malignant biliary obstruction (MBO), but the best treatment option for cholecystitis has not been determined. Here, we aimed to identify the risk factors of cholecystitis after SEMS placement and determine the best treatment option. METHODS: Incidence, treatments, and predictive factors of cholecystitis were retrospectively evaluated in 1084 patients with distal MBO (DMBO) and 353 patients with hilar MBO (HMBO) who underwent SEMS placement at 12 institutions from January 2012 to March 2021. RESULTS: Cholecystitis occurred in 7.5% of patients with DMBO and 5.9% of patients with HMBO. The recurrence rate was significantly lower (P = .043) and the recurrence-free period significantly longer (P = .039) in endoscopic procedures than in percutaneous procedures for cholecystitis treatment. EUS-guided gallbladder drainage (EUS-GBD) was better in terms of technical success, procedure time, and recurrence-free period than endoscopic transpapillary gallbladder drainage. Obstruction across the cystic duct orifice by tumor (P = .015) and by stent (P = .037) were independent risk factors for cholecystitis in DMBO. Cases with multiple SEMS placements (odds ratio [OR], 11; 95% confidence interval [CI], 0.68-190; P = .091) and with gallbladder stones (OR, 2.3; 95% CI ,0.92-5.6; P = .075) had a higher risk for cholecystitis in HMBO. CONCLUSIONS: The incidences of cholecystitis after SEMS placement for DMBO and HMBO were similar. EUS-GBD is the optimal treatment option for patients with cholecystitis after SEMS placement for MBO.

Cysts or necrotic components in pancreatic ductal adenocarcinoma is associated with the risk of EUS-FNA/B complications including needle tract seeding.

BACKGROUND: EUS-FNA/B for pancreatic ductal adenocarcinoma (PDAC) is generally considered to be safe; however, while the incidence is low, there are occurrences of complications. Among these complications, there are serious ones like needle tract seeding (NTS), and it is not known than which types of tumors have the risks of EUS-FNA/B complications. This study aimed to evaluate the risk of EUS-FNA/B complications in patients with PDAC, focusing on morphological features. METHODS: Overall, 442 patients who underwent EUS-FNA/B for solid pancreatic masses between January 2018 and May 2022 in four institutions were retrospectively surveyed. Finally, 361 patients histopathologically diagnosed with PDAC were analyzed. Among these patients, 79 tumors with cysts or necrotic components were compared with 282 tumors without cysts or necrotic components. The incidence and risk of EUS-FNA/B complications including NTS were evaluated. RESULTS: There were 9 (2.4 %) of total EUS-FNA/B complications and 3 (0.8 %) of NTS. The incidence of total complication rate and NTS in tumors with cysts or necrotic components were significantly higher than in those without cysts or necrotic components (total complication 6.3 % vs. 1.4 %, p = 0.026, NTS 3.7 % vs. 0 %, p = 0.01). The transgastric route of puncture (OR: 93.3, 95 % CI: 3.81-2284.23) and the existence of cysts or necrotic components (OR: 7.3, 95 % CI: 1.47-36.19) were risk factors for EUS-FNA/B complications identified by the multivariate analysis. CONCLUSIONS: We should pay attention to the risks of EUS-FNA/B complications, including NTS, when the tumor has cysts or necrotic components.

The efficacy of non-anesthesiologist-administered propofol sedation with a target-controlled infusion system during double-balloon endoscopic retrograde cholangiopancreatography.

BACKGROUND: The sedation method used during double-balloon endoscopic retrograde cholangiopancreatography (DB-ERCP) differs among countries and/or facilities, and there is no established method. This study aimed to evaluate the efficacy of non-anesthesiologist-administered propofol (NAAP) sedation using a target-controlled infusion (TCI) system during DB-ERCP. METHODS: This retrospective study was conducted between May 2017 and December 2020 at an academic center. One hundred and fifty-six consecutive patients who underwent DB-ERCP were sedated by gastroenterologists using diazepam (n = 77) or propofol with a TCI system (n = 79), depending on the period. The primary endpoint was a comparison of poor sedation rates between the two groups. Poor sedation was defined as a condition requiring the use of other sedative agents or discontinuation of the procedure. Secondary endpoints were sedation-related adverse events and risk factors for poor sedation. RESULTS: Poor sedation occurred significantly more often in the diazepam sedation group (diazepam sedation, n = 12 [16%] vs. propofol sedation, n = 1 [1%]; P = 0.001). Vigorous body movements (3 or 4) (diazepam sedation, n = 40 [52%] vs. propofol sedation, n = 28 [35%]; P = 0.038) and hypoxemia (< 85%) (diazepam sedation, n = 7 [9%] vs. propofol sedation, n = 1 [1%]; P = 0.027) occurred significantly more often in the diazepam sedation group. In the multivariate analysis, age < 70 years old (OR, 10.26; 95% CI, 1.57-66.98; P = 0.015), BMI ≥ 25 kg/m2 (OR, 11.96; 95% CI, 1.67-85.69; P = 0.014), and propofol sedation (OR, 0.06; 95% CI, 0.01-0.58; P = 0.015) were associated factors for poor sedation. CONCLUSIONS: NAAP sedation with the TCI system during DB-ERCP was safer and more effective than diazepam sedation.

Involvement of gap junctions in the increased contraction of bovine oviducts at pre-ovulation observed in vitro.

In brief: Spontaneous contraction of oviductal smooth muscle is essential for gamete transport to the fertilization site in mammals. This study sheds light on the mechanism of elevated contraction amplitude in the bovine oviductal isthmus just before ovulation. Abstract: Rhythmic contraction of the oviducts is essential for transporting gametes and embryos at peri-ovulation; however, its regulatory mechanism during the estrous cycle is unclear. Meanwhile, it is reported that ion currents regulate muscle contraction. Our study aimed to clarify the involvement of ion channels and gap junctions in regulating oviductal motility during the estrous cycle in cattle. The isthmic sections of bovine oviducts collected just after ovulation (0-4 days after ovulation), at the mid-late luteal stage (10-17 days), and at the follicular stage (1-3 days before ovulation) were used in the experiments. The frequency and amplitude of contraction of the oviductal strips in the longitudinal direction were examined using the Magnus system. The frequency was not different among the estrous stages. Conversely, the amplitude was significantly higher at the follicular stage. The blockers of voltage-dependent calcium channels, both IP3 receptor and ryanodine receptors, chloride channel, and gap junction reduced the amplitude. Additionally, mRNA and protein expression of GJA1, a component of the gap junction, in the smooth muscle tissues of the oviductal isthmus were significantly higher in the follicular stage. In addition, estradiol-17ß (E2; 1.0 ng/mL) significantly increased GJA1 mRNA expression in cultured smooth muscle tissues after 24 h and GJA1 protein expression in cultured smooth muscle cells after 48 h. These results suggest that local levels of E2 in the oviductal isthmus ipsilateral to an ovary with a dominant follicle support the increased contraction amplitude of bovine ipsilateral oviducts by elevating the gap junction expression.

Bilateral verses bilateral with tri-segmental endoscopic drainage using metal stents for high-grade malignant hilar biliary obstructions: A multicenter, randomized controlled trial: BRAVE study (BRAVE study).

INTRODUCTION: Bilateral endoscopic drainage with self-expanding metallic stent (SEMS) can be used to manage hilar malignant biliary obstruction (HMBO) more effectively in comparison to unilateral drainage. An increased drainage area is predicted to prolong stent patency and patient survival. However, few reports have described the utility of trisegmental drainage and the benefits of using trisegmental drainage remain unknown. Thus, we launched a randomized clinical trial (RCT) to compare the clinical outcomes between bilateral and trisegmental drainage using SEMSs in patients with high-grade HMBO. METHODS AND ANALYSIS: This study was conducted as a multicenter randomized control trial (RCT) in 8 high-volume medical centers in Japan, and will prove the non-inferiority of bilateral drainage to trisegmental drainage. Patients with unresectable HMBO with Bismuth type IIIa or IV who pass the inclusion and exclusion criteria will be randomized to receive bilateral or trisegmental drainage at a 1:1 ratio. At each center, the on-site study investigators will obtain informed consent from the candidates, and will use an electronic data capture system (REDCap) to input necessary information, and register candidates with the registration secretariat. The primary endpoint is the rate of non-recurrent biliary obstruction (RBO) at 180 days after SEMSs placement. A -10% non-inferiority margin is assumed in the statistical analysis of the primary endpoint. Secondary endpoints include the rate of technical and clinical success, time to recurrent biliary obstruction (TRBO), causes of RBO, procedure-related adverse events (AEs), procedure time, TRBO with or without endoscopic sphincterotomy, overall survival, and the technical and clinical success rates at reintervention. DISCUSSION: If the non-inferiority of bilateral drainage is demonstrated, it is predicted that the procedure time will be shortened and the medical cost will be reduced, which will be beneficial to the patient and the medical economy. TRIAL REGISTRATION: Registered in Japan Registry of Clinical Trial-Registration (trial number. jRCTs062220038). This version number 1. Protocol dated Jun 23, 2022.

Double guidewire technique stabilization procedure for endoscopic ultrasound-guided hepaticogastrostomy involving modifying the guidewire angle at the insertion site.

BACKGROUND AND AIMS: Endoscopic ultrasonography-guided hepaticogastrostomy (EUS-HGS) is often performed using a single guidewire (SGW), but the efficacy of the double guidewire (DGW) technique during endoscopic ultrasonography-guided biliary drainage has been reported. We evaluated the efficacy of the DGW technique for EUS-HGS, focusing on the guidewire angle at the insertion site. METHODS: This retrospective cohort study included consecutive patients who underwent EUS-HGS between April 2012 and March 2021. We measured the guidewire angle at the insertion site using still fluoroscopic imaging. We compared the clinical outcomes of EUS-HGS with the DGW and SGW techniques. The factors associated with successful cannula insertion, need for additional fistula dilation and adverse event rate were assessed by a logistic regression multivariable analysis. RESULTS: The DGW group showed higher technical (p = 0.020) and clinical success rates (p = 0.016) than the SGW group, which showed more adverse events (p = 0.017) than the DGW group. Successful cannula insertion was associated with a guidewire angle > 137° and an uneven double-lumen cannula. The DGW technique made the guidewire angle obtuse at the insertion site (p < 0.0001). A guidewire angle ≤ 137° (OR, 35.6; 95% CI, 1.70-744; p = 0.0045) and intrahepatic bile duct diameter of the puncture site ≤ 3.0 mm (OR, 14.4; 95% CI, 1.37-152; p = 0.0056) were risk factors for needing additional fistula dilation in a multivariate analysis, and additional dilation was a significant predictive factor for adverse events (OR, 8.3; 95% CI, 0.9-77; p = 0.026). CONCLUSIONS: The DGW technique can modify the guidewire angle at the insertion site and facilitate stent deployment with few adverse events.

Endoscopic removal of proximally migrated stents using a double-balloon enteroscope in patients with bowel reconstruction (with video).

Endoscopic migrated stent removal using a balloon-assisted enteroscope is technically difficult in patients with bowel reconstruction. We report the treatment outcomes and endoscopic removal methods for migrated stents using a double-balloon enteroscope (DBE). We retrospectively studied 12 patients with stent migration into the main pancreatic duct (MPD) or bile duct who underwent bowel reconstruction between January 2012 and June 2020. The successful removal rates in the MPD (n = 3) and the bile duct (n = 9) were 66.7% (2/3) and 88.9% (8/9), respectively. The removal techniques included the indirect method (n = 3), the direct method (n = 4), and a combination of indirect and direct methods (n = 3). The removal devices included an extraction balloon catheter (n = 7), basket catheter (n = 5), biopsy forceps (n = 3), and snare (n = 2). Stent removal using a DBE was feasible and useful as the first treatment for patients with bowel reconstruction. The choice of the direct and/or indirect method according to the situation of the migrated stent is important.

Application of convolutional neural networks for evaluating the depth of invasion of early gastric cancer based on endoscopic images.

BACKGROUND AND AIM: Recently, artificial intelligence (AI) has been used in endoscopic examination and is expected to help in endoscopic diagnosis. We evaluated the feasibility of AI using convolutional neural network (CNN) systems for evaluating the depth of invasion of early gastric cancer (EGC), based on endoscopic images. METHODS: This study used a deep CNN model, ResNet152. From patients who underwent treatment for EGC at our hospital between January 2012 and December 2016, we selected 100 consecutive patients with mucosal (M) cancers and 100 consecutive patients with cancers invading the submucosa (SM cancers). A total of 3508 non-magnifying endoscopic images of EGCs, including white-light imaging, linked color imaging, blue laser imaging-bright, and indigo-carmine dye contrast imaging, were included in this study. A total of 2288 images from 132 patients served as the development dataset, and 1220 images from 68 patients served as the testing dataset. Invasion depth was evaluated for each image and lesion. The majority vote was applied to lesion-based evaluation. RESULTS: The sensitivity, specificity, and accuracy for diagnosing M cancer were 84.9% (95% confidence interval [CI] 82.3%-87.5%), 70.7% (95% CI 66.8%-74.6%), and 78.9% (95% CI 76.6%-81.2%), respectively, for image-based evaluation, and 85.3% (95% CI 73.4%-97.2%), 82.4% (95% CI 69.5%-95.2%), and 83.8% (95% CI 75.1%-92.6%), respectively, for lesion-based evaluation. CONCLUSIONS: The application of AI using CNN to evaluate the depth of invasion of EGCs based on endoscopic images is feasible, and it is worth investing more effort to put this new technology into practical use.

Propofol sedation with a target-controlled infusion pump in elderly patients undergoing ERCP.

BACKGROUND AND AIMS: Advanced age is an important risk factor for adverse events (AEs) during propofol sedation for endoscopic procedures. This study aimed to evaluate the safety and efficacy of nonanesthesiologist-administered propofol (NAAP) sedation with a target-controlled infusion (TCI) system in elderly patients during ERCP. METHODS: This study retrospectively analyzed 482 patients who underwent ERCP under propofol sedation with a TCI system at Iwakuni Medical Center between January 2014 and October 2016. Patients were divided into 3 groups according to their age: group A, <70 years (n = 130); group B, ≥70 and <85 years (n = 224); and group C, ≥85 years (n = 125). We compared the propofol dose and AEs during ERCP. RESULTS: The median total infusion dose and minimum and maximum target blood concentrations of propofol were 336 mg, 2.2 µg/mL, and 2.2 µg/mL in group A; 184 mg, 1.0 µg/mL, and 1.4 µg/mL in group B; and 99 mg, .6 µg/mL, and 1.0 µg/mL in group C, respectively, with older groups requiring a lower dose (P < .0001). Hypotension was observed in 23 patients (4.8%), with no significant difference between groups (group A, 2.3%; group B, 6.3%; group C, 4.8%; P = .24). Hypoxemia was observed in 16 patients (3.3%), with no significant difference between groups (group A, 3.1%; group B, 4.9%; group C, .8%; P = .17). All AEs were immediately resolved, and no procedures were aborted. CONCLUSIONS: NAAP sedation with a TCI system during ERCP may be acceptable in elderly patients with a lower dose of propofol than that used in younger patients.

Impact of cognitive function on oral perception in independently living older people.

OBJECTIVES: Oral tactile perception is important for better mastication, appetite, and enjoyment of food. However, previous investigations have not utilized comprehensible variables thought to have negative effect on oral perception, including aging, denture wearing, and cognitive function. The aim of this study was to elucidate the impact of cognitive function on oral perception in independently living older individuals. MATERIALS AND METHODS: The study sample was comprised of 987 participants (466 males, 521 females; age 69-71 years). Oral examinations, assessments of cognitive function in preclinical level by Montreal Cognitive Assessment (MoCA)-J, and determination of oral stereognostic ability as an indicator of oral perception were performed. Related variables were selected by univariate analyses; then, multivariate logistic regression model analysis was conducted. RESULTS: Univariate analyses revealed that number of teeth, removable dentures usage, and cognitive function respectively had a significant relationship with stereognostic score. Next, the subjects were classified into good and poor perception groups (lowest 17.4%) according to oral stereognostic ability. Logistic regression analysis revealed that lower cognitive function was significantly associated with poor oral perception (OR = 0.934, p = 0.017) after controlling for other variables. CONCLUSIONS: Cognitive decline even in preclinical stage was associated with reduced oral perception after controlling for gender, tooth number and denture use in independent living older people. CLINICAL RELEVANCE: This study suggested that preclinical level of change in cognitive function affected oral perception. Dental practitioners and caregivers may need to pay attention to reduced oral perception among older people even if they do not have trouble in daily life.

Influence of lack of posterior occlusal support on cognitive decline among 80-year-old Japanese people in a 3-year prospective study.

AIM: Previous studies have reported significant associations between tooth loss or periodontal status and cognitive function; however, animal experimental studies have shown that occlusion might be a more important factor in cognitive decline. The purpose of the present study was to investigate the influence of a lack of posterior occlusal support by residual teeth on the decline of cognitive function over a 3-year period among 80-year-old Japanese people. METHODS: Participants were community-dwelling older adults (n = 515, age 79-81 years). Cognitive function was measured using the Japanese version of the Montreal Cognitive Assessment. At baseline, participants were divided into two groups: those with and without posterior occlusal support. Participants whose Japanese version of the Montreal Cognitive Assessment score decreased by ≥3 points over the 3-year period were defined as the declined group. Logistic regression was carried out for the decline in Japanese version of the Montreal Cognitive Assessment scores, including dental status and possible risk factors as independent variables. RESULTS: More participants without posterior occlusal support tended to be in the cognitive decline group (49.4%) than in the maintained group (38.5%; χ2 -test, P = 0.02). Logistic regression analysis showed that a lack of posterior occlusal support was a significant variable (odds ratio 1.55, P = 0.03) for cognitive decline, even after adjusting for other risk factors. However, the number of teeth or mean periodontal pocket depth was not significantly correlated with cognitive decline. CONCLUSIONS: The present findings suggest that a lack of posterior occlusal support predicted the incidence of cognitive decline, even after adjusting for possible risk factors in community-dwelling old-old people. Geriatr Gerontol Int 2018; 18: 1439-1446.

Association of handgrip strength with various oral functions in 82- to 84-year-old community-dwelling Japanese.

OBJECTIVE: The purpose of this study was to elucidate the associations between muscle strength and several oral functions in a large cohort of community-dwelling, 82- to 84-year-old community-dwelling Japanese people. BACKGROUND DATA DISCUSSING THE PRESENT STATUS OF THE FIELD: Several studies have examined the relationships between physical performance and oral functions. However, no studies have investigated the associations of muscle strength with various objectively evaluated oral functional parameters in a large cohort of very old adults. MATERIALS AND METHODS: This study included 809 community-dwelling Japanese people (407 men and 402 women) aged 82-84 years. The oral functions examined were the maximal occlusal force, masticatory performance, stimulated salivary flow rate, repetitive saliva-swallowing test (RSST) score, tongue pressure and mouth-opening distance. Handgrip strength was measured, and its correlations with oral functions were assessed. Multiple linear and logistic regression analyses were performed to investigate the relationships between oral functions and handgrip strength. RESULTS: Multivariate analysis revealed that handgrip strength was correlated with not only the maximal occlusal force, masticatory performance and tongue pressure but also the RSST score and mouth-opening distance after adjustment for sex, number of teeth, use of removable denture, periodontal condition, instrumental activities of daily living, body mass index. When we examine the elderly people whose handgrip strength is declining, we should predict that their various oral functions may be declining. CONCLUSION: Handgrip strength was related to various oral functions after adjustment for the number of teeth in this population of community-dwelling 82- to 84-year-old Japanese.

Erratum to "Characterizations of oral microbiota in elderly nursing home residents with diabetes".

The publisher regrets that in the above-mentioned article, there was an error in the list of references. The reference numbers "29-32" should be "28-31".

Composition of salivary microbiota in elderly subjects.

Frailty is gaining attention worldwide with the aging of society. Despite the potential lethality and multiple signs and symptoms in affected individuals, preclinical detection of early manifestations leading to frailty syndrome have not been established. We speculated that the composition of the oral microbiota is associated with general frailty, as well as a relationship between gut microbiota and general health condition. In the present study, we investigated the salivary microbiota composition in samples from healthy and frail elderly individuals using 16S rRNA sequencing analysis for characterization. We found a significant difference in diversity between elderly individuals living in a nursing home (EN) and healthy control (HC) subjects, as well as in the microbiota composition at the phyla level. A supervised orthogonal partial least squared discriminant analysis (OPLS-DA) revealed a significant difference in clear classification trend between the EN and HC groups, with all observations falling within the Hotellings T2 (0.95) ellipse, with model fitness parameters of R 2(cum) = 0.937 and Q 2(cum) = 0.888, respectively. In addition, the score plots by unsupervised principal component analysis (PCA) showed a clear classification trend in both groups. Our findings suggest that general frailty is associated with oral microbiota composition and formation.

Occlusal force is correlated with cognitive function directly as well as indirectly via food intake in community-dwelling older Japanese: From the SONIC study.

BACKGROUND: Growing evidence suggests that oral health may be an important factor associated with cognitive function in aged populations. However, many previous studies on this topic used insensitive oral indicators or did not include certain essential covariates. Thus, we examined the association between occlusal force and cognitive function in a large sample of older adults, controlling for dietary intake, vascular risk factors, inflammatory biomarkers, depression, and genetic factors. METHODS: In this cross-sectional study of older community-dwelling Japanese adults, we examined data collected from 994 persons aged 70 years and 968 persons aged 80 years. Cognitive function was measured using the Japanese version of the Montreal Cognitive Assessment (MoCA-J). Oral status and function were evaluated according to the number of remaining teeth, periodontal pocket depth, and maximal occlusal force. Associations between MoCA-J scores and occlusal force were investigated via bivariate and multivariate analyses. RESULTS: Education level, financial status, depression score, and intake of green and yellow vegetables, as well as number of teeth and occlusal force, were significantly correlated with MoCA-J scores in both age groups. Among individuals aged 80 years, CRP and periodontal status were weakly but significantly associated with MoCA-J score. After controlling for all significant variables via bivariate analyses, the correlation between maximal occlusal force and cognitive function persisted. A path analysis confirmed the hypothesis that cognitive function is associated with occlusal force directly as well as indirectly via food intake. CONCLUSIONS: After controlling for possible factors, maximal occlusal force was positively associated with cognitive function directly as well as indirectly through dietary intake.

Characterizations of oral microbiota in elderly nursing home residents with diabetes.

Over 700 bacterial species have been detected in the oral cavity. Several studies have suggested that periodontitis is associated with systemic disorders such as diabetes mellitus, indicating a key role for oral microbiota in human health. However, the relationship between oral microbiota and diabetes has not been well clarified. Therefore, we conducted microbiome analysis of saliva samples obtained from 15 elderly residents (3 with type 2 diabetes mellitus [DM] and 12 without diabetes [non-DM]) at three different nursing homes, as well as 9 young healthy controls (HC). Genomic DNA was extracted from each sample, and then the V4 region of the 16S rRNA gene was amplified and sequenced. Alpha diversity, in terms of operational taxonomic unit richness, was significantly higher in samples from the non-DM group than in those from the HC group. Weighted UniFrac distance analysis showed that salivary microbial communities in the DM group were separately clustered. Furthermore, in the DM group, Actinomyces and Selenomonas showed significantly higher abundance, whereas Alloprevotella showed significantly lower abundance, relative to the non-DM group. Although our findings were limited by the small sample size, oral bacterial diversity in the DM group was clearly different from that in the non-DM group.

Microbiological assessment of effects of clinical mouth rinses on common oral microbes.

Dry mouth occurs frequently in aged individuals, as well as in patients who are hospitalized, receiving multiple drugs, undergoing radiation treatment to the head and neck, or wearing a removable denture prosthesis, use of mouth rinse being often an option for relief. In the present study, we performed microbiological assessments of subjects given three different commercially available mouth rinses commonly employed in clinical practice (Peptisal, Biotène, ConCool) to determine their effects. For bacterial clearance in vitro, Peptisal showed the highest level of suppression of oral indigenous bacteria found in both planktonic formations and biofilm. Furthermore, the inhibitory effects of these agents on biofilm formation on acrylic resin plates were examined using scanning electron microscopy. Again, Peptisal proved superior, because acquisition of resistance to antimicrobial peptides by a sensitive microbial strain was rarely observed. We conclude that Peptisal is an effective mouth rinse for clearance of planktonic and biofilm microorganisms present in the oral cavity.

Streptococcus pyogenes Endopeptidase O Contributes to Evasion from Complement-mediated Bacteriolysis via Binding to Human Complement Factor C1q.

Streptococcus pyogenes secretes various virulence factors for evasion from complement-mediated bacteriolysis. However, full understanding of the molecules possessed by this organism that interact with complement C1q, an initiator of the classical complement pathway, remains elusive. In this study, we identified an endopeptidase of S. pyogenes, PepO, as an interacting molecule, and investigated its effects on complement immunity and pathogenesis. Enzyme-linked immunosorbent assay and surface plasmon resonance analysis findings revealed that S. pyogenes recombinant PepO bound to human C1q in a concentration-dependent manner under physiological conditions. Sites of inflammation are known to have decreased pH levels, thus the effects of PepO on bacterial evasion from complement immunity was analyzed in a low pH condition. Notably, under low pH conditions, PepO exhibited a higher affinity for C1q as compared with IgG, and PepO inhibited the binding of IgG to C1q. In addition, pepO deletion rendered S. pyogenes more susceptible to the bacteriocidal activity of human serum. Also, observations of the morphological features of the pepO mutant strain (ΔpepO) showed damaged irregular surfaces as compared with the wild-type strain (WT). WT-infected tissues exhibited greater severity and lower complement activity as compared with those infected by ΔpepO in a mouse skin infection model. Furthermore, WT infection resulted in a larger accumulation of C1q than that with ΔpepO. Our results suggest that interaction of S. pyogenes PepO with C1q interferes with the complement pathway, which enables S. pyogenes to evade complement-mediated bacteriolysis under acidic conditions, such as seen in inflammatory sites.

Age and sex differences in the taste sensitivity of young adult, young-old and old-old Japanese.

AIM: The present study examined sex and age differences in taste sensitivity among young adult, young-old and old-old Japanese. METHODS: Participants were divided into three groups comprising 477 men and 519 women in the young-old group (aged 69-71 years), 449 men and 500 women in the old-old group (aged 79-81 years), and 35 men and 35 women in the young adult group (aged 24-32 years). Recognition thresholds for the four basic tastes were measured using the 1-mL whole mouth gustatory test, in which taste solutions of the four basic tastes were tested in five concentrations. RESULTS: Young adults showed significantly lower recognition thresholds than the young-old group, and the young-old group showed significantly lower recognition thresholds than the old-old group. Among the young-old and old-old groups, women showed significantly lower recognition thresholds than males for sour, salty and bitter tastes, but there was no sex difference in the sweet taste threshold between the two groups. CONCLUSIONS: The present study confirmed that there are age and sex differences in taste sensitivity for the four basic tastes among young adult, young-old, and old-old Japanese, and that the sensitivity of sweet taste is more robust than the other tastes. Geriatr Gerontol Int 2016; 16: 1281-1288.

Submucosal tumor-like lesion originating from colon tuberculosis: a case report and review of the literature.

A 76-year-old male had a solitary submucosal tumor-like lesion in the sigmoid colon originating from tuberculosis. The lesion, up to 1 cm in diameter, was found incidentally during a routine colonoscopy, which revealed a protuberant submucosal growth with a shallow depression of the overlying mucosa in the center of the tumor. Histologically, the endoscopic biopsy revealed caseating granulomas and infiltration of Langhans giant cells and epithelioid cells, consistent with tuberculosis, were also observed. Five reports of similar lesions from colon tuberculosis were found in a literature review, including the present case. In all cases, the submucosal tumor-like lesions which originated from tuberculosis were small and in an active stage of tuberculosis. Five cases of submucosal tumor-like lesions from gastric tuberculosis were also reported, with characteristics very similar to those of the lesions from colon tuberculosis. Therefore, we propose that lesions originating from tuberculosis should be included in the differential diagnosis of submucosal tumor-like lesions in the colon and stomach.