Visceral adipose tissue reduction measured by deep neural network architecture improved reflux esophagitis endoscopic grade

BACKGROUND AND AIMS

Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE.

METHODS

Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal computed tomography (CT) at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included. Visceral and subcutaneous adipose tissue areas and volumes were measured using a deep neural network architecture and CT. The association between the abdominal adipose tissue area and volume and the risk of RE was evaluated. Participants who underwent follow-up EGD and abdominal CT were selected; the effects of changes in abdominal adipose tissue area and volume on RE endoscopic grade were investigated using Cox proportional hazards regression.

RESULTS

We enrolled 6570 patients who underwent EGD and abdomen CT on the same day. RE was associated with male sex, hypertension, diabetes, excessive alcohol intake, current smoking status, and levels of physical activity. The VAT area and volume increased the risk of RE dose-dependently. A decreasing VAT volume was significantly associated with improvement in RE endoscopic grade (HR:3.22, 95%CI:1.82-5.71). Changes in subcutaneous adipose tissue volume and the disease course of RE were not significantly correlated.

CONCLUSIONS

Visceral obesity is strongly associated with RE. VAT volume reduction was prospectively associated with improvement in RE endoscopic grade dose-dependently. Visceral obesity is a potential target for RE treatment.

Boston bowel preparation scale score 6 has more missed lesions compared with 7-9

Adequate bowel preparation is an important factor in high-quality colonoscopy. It is generally accepted that a Boston Bowel Preparation Scale (BBPS) score ≥ 6 is adequate, but some reports suggest ≥ 7. Subjects who underwent colonoscopy at least twice within 3 years from August 2015 to December 2019 were included. Polyp detection rates (PDRs), adenoma detection rates (ADRs), and number of polyps including adenomas were compared stratified by baseline colonoscopy (C1) BBPS score. Among 2352 subjects, 529 had BBPS 6 (group 1) and 1823 had BBPS 7-9 (group 2) at C1. There was no significant difference in PDR or ADR at C1 and follow-up colonoscopy (C2) between the two groups. However, the numbers of polyps (1.84 vs. 1.56, P = 0.001) and adenomas (1.02 vs. 0.88, P = 0.034) at C2 were significantly higher in group 1 than group 2, respectively. Segmental BBPS score 2 in group 1 compared to group 2, especially, showed higher PDR (P = 0.001) and ADR (P = 0.007) at C2. BBPS 6 is associated with a higher number of polyps and adenomas in short-term follow-up colonoscopy than BBPS 7-9. To reduce the risk of missed polyps, a thorough examination is necessary for BBPS 6.

[Predictive value of serum Gal-13, GLP-1 and VEGF levels in adverse pregnancy outcomes of gestational diabetes mellitus]

To explore the application value of serum Gal-13, GLP-1 and VEGF in the prevention and guidance of adverse pregnancy outcomes in gestational diabetes (GDM). A retrospective study with case-control method was used to select 1 012 GDM patients from Haikou Maternal and Child Health Hospital from January 2019 to December 2022 as the study objects, and they were divided into poor pregnancy outcome group (n=342) and good pregnancy outcome group (n=670) according to whether they had adverse pregnancy outcomes. The medical records of 521 healthy women with normal glucose metabolism were selected as the control group. Serum Gal-13 and GLP-1 were detected by enzyme-linked immunosorbent assay and VEGF was determined by IAMMGE specific protein analyzer. After comparing the differences of the above factors among the three groups, multivariate logistic regression model was used to analyze the influencing factors of adverse pregnancy outcomes in GDM patients, and ROC curve was drawn to analyze the predictive value of serum Gal-13, GLP-1 and VEGF levels on adverse pregnancy outcomes in GDM patients. The results showed that Fasting blood glucose (FPG), glycosylated hemoglobin (HbA1c) and fasting insulin (FINS) in the adverse pregnancy outcome group were 5.92(4.98, 6.41) mmol/L, 5.32(4.96, 5.47)%, 62.56(49.21,99.50) pmol/L, VEGF was 495.47(389.14, 567.13) ng/L, TSH was 1.48(1.34, 1.58) mIU/L, right ventricular myocardial work index (Tei index) was 0.59(0.45, 0.67), 89 cases of elderly parturients; FPG was 4.45(4.16, 5.03) mmol/L, HbA1c was 5.04(4.86, 5.29)%, FINS was 57.41(46.90, 74.08) pmol/L, VEGF was 405.84(348.02, 462.68) ng/L, TSH was 1.42(1.25, 1.50) mIU/L, Tei index was 0.50(0.47, 0.64), there were 142 cases of old women. In the control group, FPG was 4.33(4.05, 4.75) mmol/L, HbA1c was 5.01(4.13, 5.18)%, FINS was 38.48(36.76, 41.72) pmol/L and VEGF was 302.45(283.14, 336.56) ng/L, TSH was 1.32(1.24, 1.47)mIU/L, Tei index was 0.48(0.39, 0.59), and there were 106 elderly parturiencies. The levels of FPG, HbA1c, FINS, VEGF, TSH and Tei index in the adverse pregnancy outcome group and the good pregnancy outcome group were higher than those in the control group, and the proportion of elderly parturients was higher than that in the control group, and the adverse pregnancy outcome group was higher than that in the good pregnancy outcome group. The differences were statistically significant (H=8.620, P<0.001, H=2.616, P=0.014, H=6.156, P<0.001, H=3.051, P<0.001, H=4.892, P=0.044, χ2=2.548, P=0.045). In the adverse pregnancy outcome group, Gal-13 was 15.27(8.35, 24.45)pg/ml, GLP-1 was 9.27(8.26, 12.35) pmol/L and FT4 was 11.59(9.67, 13.48) pmol/L. In the group with good pregnancy outcome, Gal-13 was 25.34(20.14, 29.73) pg/ml, GLP-1 was 12.38(10.25, 15.63) pmol/L and FT4 was 13.86(10.67, 15.10) pmol/L. In the control group, Gal-13 was 31.21(27.48, 34.45) pg/ml, GLP-1 was 11.34(10.40, 14.37) pmol/L and FT4 was 14.15(10.75, 15.43)pmol/L. The levels of Gal-13, GLP-1 and FT4 in the adverse pregnancy outcome group and the good pregnancy outcome group were significantly lower than those in the control group, and the adverse pregnancy outcome group was lower than that in the good pregnancy outcome group. The differences were statistically significant (H=6.458, P=0.011, H=8.445, P<0.001, H=5.694, P<0.001). The levels of Gal-13 and GLP-1 in normal blood glucose recovery group were higher than those in non-normal blood glucose recovery group, and the levels of VEGF were lower than those in non-normal blood glucose recovery group (P<0.05).In multivariate logistic regression analysis, Gal-13, GLP-1, VEGF, TSH, FT4 and Tei indexes were independent influencing factors for adverse pregnancy outcomes with GDM (P<0.05). ROC curve analysis showed that the AUC of Gal-13, GLP-1 and VEGF alone in predicting adverse pregnancy were 0.779, 0.761 and 0.615, respectively. The value of the combined diagnosis was the highest (AUC=0.912), the sensitivity was 90.1%, and the specificity was 80.0%. In conclusion, Gal-13, GLP-1 and VEGF may be independent influencing factors for adverse pregnancy outcomes in GDM patients, and the combined detection of the three may help to improve the auxiliary diagnostic efficacy for predicting adverse pregnancy outcomes.

Retraction: Bio-inspired terpolymers containing dopamine, cations and MPC: a versatile platform to construct a recycle antibacterial and antifouling surface

Retraction of 'Bio-inspired terpolymers containing dopamine, cations and MPC: a versatile platform to construct a recycle antibacterial and antifouling surface' by B. L. Wang et al., J. Mater. Chem. B, 2015, 3, 5501-5510, https://doi.org/10.1039/C5TB00597C.

Regulation of psoriasis, colitis, and the intestinal microbiota by clusterin

Psoriasis, a chronic and systemic inflammatory disorder characterized by activation of the interleukin (IL)-23/IL-17 axis, may be associated with the intestinal microbiota through the so-called "gut-skin axis." Clusterin is a glycoprotein ubiquitously distributed in mammalian tissues; however, its role in psoriasis is unclear. Therefore, we evaluated the role of clusterin in psoriatic skin inflammation, systemic inflammation, and colitis using a murine model of IMQ-induced psoriasis. In IMQ-treated clusterin-knockout (clusterin-/-) mice, the expressions of inflammatory cytokines in clusterin-silenced human keratinocytes and intestinal microbial composition were analyzed. We also examined clusterin expression in the skin tissues of patients with psoriasis. IMQ-induced psoriatic skin inflammation is suppressed in clusterin-/- mice. Long-term administration of IMQ induced systemic inflammation and colitis; however, both were alleviated by the genetic deletion of clusterin. Genetic silencing of clusterin in human keratinocytes inhibited the production of inflammatory cytokines involved in the initiation and progression of psoriasis. The composition of the intestinal microbiota in IMQ-treated clusterin-/- and wild-type mice was different. Genetic deletion of clusterin suppressed the increase in the Firmicutes/Bacteroidetes (F/B) ratio. Skin tissues of patients with psoriasis showed high clusterin expression. In conclusion, inhibition of clusterin decreased psoriatic skin inflammation, systemic inflammation, colitis, and altered the F/B ratio in an IMQ-induced murine psoriasis model.

Atopic dermatitis is associated with the clinical course of inflammatory bowel disease

OBJECTIVES

There are a few studies about the relationship between inflammatory bowel disease (IBD) and atopic dermatitis (AD). It is implied that both diseases have common pathophysiologic mechanisms and can affect each other. However, little information is available on the effect of AD on the clinical course of patients with IBD.

METHODS

This is a multi-center, retrospective, observational study. We define AD as a chronic eczematoid dermatosis diagnosed by dermatologists. Patients with concurrent IBD and AD were defined as a case group. Age, gender, and IBD subtype-matched patients without AD were included as a reference group.

RESULTS

The numbers of patients in the case and reference groups were 61 and 122 respectively. There was a significantly shorter biologics-free survival in the case group than that in the reference group according to the multivariable-adjusted Cox regression analysis with the onset age, disease duration, smoking status, use of steroid, use of immunomodulator, initial C-reactive protein, initial erythrocyte sedimentation rate, presence of other allergic diseases and initial disease severity [hazard ratio (HR) 1.828, 95% confidence interval (CI) 1.022-3.271, p = .042]. The trend was consistent in the subgroup analysis with ulcerative colitis (HR 3.498, 95% CI 1.066-11.481, p = .039), but not with Crohn's disease (HR 1.542, 95% CI 0.720-3.301, p = .265).

CONCLUSIONS

AD showed a significant effect on the biologics-free survival of patients with IBD and especially the UC subtype. Further mechanistic research is required to elucidate the pathogenesis of AD on the clinical course of IBD.

The Relationship Between Rosacea and Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

INTRODUCTION

Rosacea and inflammatory bowel disease (IBD) are chronic inflammatory disorders of the skin and the gut, which are interfaces between the environment and the human body. Although growing evidence has implicated a possible link between rosacea and IBD, it remains unclear whether IBD increases the risk of rosacea and vice versa. Therefore, we investigated the association between rosacea and IBD in this study.

METHODS

We performed a systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines.

RESULTS

Eight eligible studies were included in this meta-analysis. Overall, the prevalence of rosacea was higher in the IBD group than in the control group, with a pooled odds ratio (OR) of 1.86 (95% confidence interval [CI](1), 1.52-2.26). Both the Crohn's disease and the ulcerative colitis groups had higher prevalences of rosacea than the control group, with ORs of 1.74 (95% CI 1.34-2.28) and 2.00 (95% CI 1.63-2.45), respectively. Compared with those in the control group, the risks of IBD, Crohn's disease, and ulcerative colitis were significantly higher in the rosacea group, with incidence rate ratios of 1.37 (95% CI 1.22-1.53), 1.60 (95% CI 1.33-1.92), and 1.26 (95% CI 1.09-1.45), respectively.

CONCLUSION

Our meta-analysis suggests that IBD is bidirectionally associated with rosacea. Future interdisciplinary studies are needed to better understand the mechanism of interaction between rosacea and IBD .

[Observation of the efficacy of autologous mucosal transplantation to prevent esophageal stricture after near-circumferential endoscopic submucosal dissection for early esophageal cancer]

Objective: To investigate the efficacy of autologous mucosal transplantation to prevent esophageal stricture after near-circumferential endoscopic submucosal dissection (ESD) for early esophageal cancer. Methods: The case data of 33 patients, who underwent near-circumferential ESD for early esophageal cancer and were followed up regularly in the First Affiliated Hospital of Zhengzhou University from April 2017 to July 2022, were analyzed retrospectively, including 14 males and 19 females, aged (66.4±7.4) (47-77) years. According to the different treatment methods, they were divided into 4 groups: group A (6 cases) were treated with autologous mucosa transplantation and fully covered metal stent implantation, combined with oral, intravenous and local injection of hormone; Group B (8 cases) were treated with autologous mucosa transplantation and fully covered metal stent implantation; Group C (11 cases) were treated with fully covered metal stent implantation combined with oral or intravenous hormone; Group D (8 cases) were treated with fully covered metal stent implantation. After the operation, the growth of the transplanted mucosa, esophageal stricture and surgical complications were observed by endoscopy, so as to understand the efficacy of automucosa transplantation in preventing esophageal stricture after near-circumferential ESD for early esophageal cancer. Results: The gastroscopic operation was successful in 33 patients. The times of expansion in groups B, C and D were more than that in group A, and the times of expansion [M(Q₁,Q₃)] in group A were 0(0, 1.8) times, while the times of expansion in group B, C and D were 5.5(4.3, 6.8), 4.0(4.0, 7.0) and 5.5(3.5, 10.8) times, respectively, with statistical significance (all P<0.05). There was no significant difference in times of expansion among groups B, C and D (all P>0.05). The stent placement time [M(Q₁,Q₃)] in group B [7.5(6.3, 8.8) days] was shorter than that in group A [64.5(41.5, 75.5) days] (P=0.006). There was no significant difference in stent placement time between group C [38.0(28.0, 50.0) days] and group D [31.5(27.3, 66.3) days] and group A (both P>0.05). The stent placement time in group C was longer than that in group B (P<0.05).There was no significant difference in stent placement time between group B, C and D (all P>0.05). There was no significant difference in the incidence of complications among the groups (all P>0.05). Conclusions: Autologous mucosal transplantation is safe and effective in preventing stenosis after near-circumferential ESD for early esophageal cancer. The effect of autologous mucosal transplantation combined with fully covered metal stent placement, systemic and local steroid application in preventing esophageal stricture after near-circumferential ESD for early esophageal cancer is better than that of single application.

[The mid-term effect of corneal collagen cross-linking for progressive keratoconus and the changes in rigid gas permeable contact lens fitting parameters]

Objective: To investigate the effect of corneal collagen cross-linking (CXL) for progressive keratoconus and to evaluate changes in the parameters of rigid gas permeable contact lens (RGPCL) fitting after surgery. Methods: It was a prospective cohort study. Fifty-three eyes of 41 keratoconus patients received accelerated CXL in Qingdao Eye Hospital of Shandong First Medical University from May to December 2018. There were 31 males and 10 females, aged (20.46±4.15) years. According to the corneal thickness, de-epithelial CXL (33 eyes) or trans-epithelial CXL (20 eyes) was performed. The best spectacle-corrected visual acuity, refractive power and the thinnest corneal thickness at baseline and at 6 weeks were compared. Corneal topography was performed at baseline and at 6 weeks, 3, 6 and 12 months postoperatively. Rose K RGPCLs were used before and 6 weeks after surgery, and the fitting status was monitored until 12 months after surgery. The t test was performed to analyze the difference before and after the operation. Results: The best spectacle-corrected visual acuity, refractive power, and the thinnest corneal thickness were not significantly changed over 6 weeks of follow-up, but the Kf, Ks and Kmax values were significantly increased in all patients (all P<0.05). In the de-epithelial group, the Kmax values before the operation, at 3, 6 and 12 months after the operation were (55.00±5.51) diopters (D), (54.73±5.34) D, (54.58±6.15) D and (54.20±5.49) D, respectively, and the decrease at 12 months was significant [(0.80±2.05) D; t=2.25, P=0.001]. In the trans-epithelial group, the Kmax values were (59.43±8.98) D, (57.97±8.79) D, (58.19±8.37) D and (56.94±7.19) D at the four time points, respectively, and the decreases at 3, 6 and 12 months were all significant [(1.46±2.09) D, (1.25±1.82) D, (2.49±3.64) D; t=3.12, 3.06, 3.50; P=0.006, 0.006, 0.007]. The best RGPCL-corrected visual acuity, the diameter and the average diopters of RGPCLs showed no significant change in both groups. The RGPCL base curve decreased by 0.07 mm in the de-epithelial group and by 0.13 mm in the trans-epithelial group (both P<0.05). The design of edge lifting was used in 10 eyes postoperatively in the de-epithelial group compared with 8 eyes preoperatively, and in 4 eyes postopratively in the trans-epithelial group compared with 7 eyes preoperatively. The number of eyes using the toric peripheral design of the lens was increased to 3 compared with 2 preoperatively in the de-epithelial group and from 1 to 4 in the trans-epithelial group. The acceptance rate of RGPCL fitting in both groups increased at 6 and 12 months after surgery compared to 6 weeks after surgery. Conclusions: The corneal curvature became steep slightly at 6 weeks after CXL and gradually recovered and flattened. The Kmax in the trans-epithelial group decreased earlier and more than that in the de-epithelial group. The base curve of the RGPCLs was slightly reduced after 6 weeks, and the toric peripheral design was increasingly needed, but the requirement for the design of the lifted edge was different between the two groups. A good RGPCL fitting can be achieved within 1 year after CXL.

Inverse correlation between gastroesophageal reflux disease and atrophic gastritis assessed by endoscopy and serology

BACKGROUND

Helicobacter pylori (H. pylori) infection is known to prevent the occurrence of gastroesophageal reflux disease (GERD) by inducing gastric mucosal atrophy. However, little is known about the relationship between atrophic gastritis (AG) and GERD.

AIM

To confirm the inverse correlation between AG and the occurrence and severity of GERD.

METHODS

Individuals receiving health checkups who underwent upper gastrointestinal endoscopy at Seoul National University Healthcare System Gangnam Center were included. The grade of reflux esophagitis was evaluated according to the Los Angeles classification. Endoscopic AG (EAG) was categorized into six grades. Serologic AG (SAG) was defined as pepsinogen I ≤ 70 ng/mL and pepsinogen I/II ratio ≤ 3.0. The association between the extent of EAG and SAG and the occurrence and severity of GERD was evaluated using multivariate logistic regression analysis.

RESULTS

In total, 4684 individuals with GERD were compared with 21901 healthy controls. In multivariate logistic regression analysis, advanced age, male sex, body mass index > 23 kg/m², presence of metabolic syndrome, current smoking, and alcohol consumption were associated with an increased risk of GERD. Seropositivity for H. pylori immunoglobulin G antibodies was associated with a decreased risk of GERD. There was an inverse correlation between the extent of EAG and occurrence of GERD: Odds ratio (OR), 1.01 [95% confidence interval (CI): 0.90-1.14] in C1, 0.87 (0.78-0.97) in C2, 0.71 (0.62-0.80) in C3, 0.52 (0.44-0.61) in O1, 0.37 (0.29-0.48) in O2, and 0.28 (0.18-0.43) in O3. Additionally, the extent of EAG showed an inverse correlation with the severity of GERD. The presence of SAG was correlated with a reduced risk of GERD (OR = 0.49, 95%CI: 0.28-0.87, P = 0.014).

CONCLUSION

The extent of EAG and SAG exhibited strong inverse relationships with the occurrence and severity of GERD. AG followed by H. pylori infection may be independently protect against GERD.

Non-alcoholic/Metabolic-Associated Fatty Liver Disease and Helicobacter pylori Additively Increase the Risk of Arterial Stiffness

Background

Non-alcoholic fatty liver disease (NAFLD) and Helicobacter pylori (Hp) infection have a close association with an increased risk of cardiovascular disease. Metabolic dysfunction-associated fatty liver disease (MAFLD) is characterized by metabolic dysfunction in NAFLD. We investigated the synergistic effects of NAFLD/MAFLD and Hp infection on the risk of arterial stiffness in an asymptomatic population.

Methods

We included individuals who underwent abdominal ultrasonography, anti-Hp IgG antibody evaluations and cardio-ankle vascular index (CAVI) during health screening tests between January 2013 and December 2017. Arterial stiffness was defined using CAVI. A logistic regression model was used to analyze the independent and synergistic effects of NAFLD/MAFLD and Hp infection on the risk of arterial stiffness.

Results

Among 3,195 subjects (mean age 54.7 years, 68.5% male), the prevalence of increased arterial stiffness was 36.4%. In the multivariate analysis, subjects with NAFLD but without Hp infection and those with both NAFLD and Hp infection had a significantly higher risk of increased arterial stiffness [odds ratio (OR) 1.61, 95% confidence interval (CI) 1.15–2.26, and OR 2.23, 95% CI 1.63–3.06, respectively], than subjects without Hp infection and NAFLD. Regarding MAFLD, Hp infection additively increased the risk of arterial stiffness in subjects with MAFLD (OR 2.13, 95% CI 1.64–2.78).

Conclusions

An interactive effect of Hp infection on the risk of arterial stiffness in individuals with NAFLD/MAFLD was observed. Hp infection additively increases the risk of arterial stiffness in subjects with NAFLD or MAFLD.

Impact of comprehensive optical diagnosis training using Workgroup serrAted polypS and Polyposis classification on detection of adenoma and sessile serrated lesion

OBJECTIVES

Many interventions have been attempted to improve adenoma detection rate (ADR) and sessile serrated lesion detection rate (SDR), and one of these interventions is educational training to recognize polyp characteristics. This study aimed to investigate the change in polyp detection rates of endoscopists before and after comprehensive training through the Gangnam-Real Time Optical Diagnosis (Gangnam-READI) program.

METHODS

Fifteen gastroenterologists participated in a 1-year comprehensive training program that consisted of ex vivo and in vivo training that encompasses knowledge and skills in endoscopic characterization of colonic polyps using the Workgroup serrAted polypS and Polyposis (WASP) classification. We evaluated the impact of the training program by comparing the overall and individual ADR and SDR 6 months before and after the training.

RESULTS

Overall, 18,280 polyps (9337 adenomas and 855 sessile serrated lesion) were collected. The optical diagnosis training had no significant impact on the difference in ADR after training compared to before training (47.7% vs. 46.5%, P = 0.608). A tendency for a decrease in ADR variance was noted among the endoscopists after training (74.9 vs. 32.7, P = 0.121). The overall pre-training period SDR was 4.5% and showed a statistically significant increase to 5.6%, 8.0%, and 7.1% in the first and second half of the training period, and post-training period, respectively (P = 0.003). The optical diagnosis training did not decrease variance in SDR (8.9 vs. 8.8, P = 0.985).

CONCLUSION

Comprehensive optical diagnosis training with WASP classification has a significant impact on increasing the overall SDR of expert endoscopists.

Small sessile serrated polyps might not be at a higher risk for future advanced neoplasia than low-risk adenomas or polyp-free groups

BACKGROUND

Polypectomy surveillance colonoscopy is recommended according to the risk stratification of initially removed polyps. This study aimed to evaluate the risk of advanced neoplasia following low-risk SSPs compared with that following LRAs and polyp-free groups.

MATERIALS AND METHODS

From September 2013 to August 2017, asymptomatic Koreans aged 50-75 years who underwent surveillance colonoscopy post-baseline colonoscopy were enrolled. The 1314 participants who met the study design criteria were stratified into three groups according to the presence of LRAs or low-risk SSPs. The rate of advanced neoplasia was then compared between groups by surveillance colonoscopy.

RESULTS

A total of 1314 participants were classified according to baseline colonoscopy findings: no polyp (n = 551), LRA (n = 707), and low-risk SSP (n = 56). All participants underwent surveillance colonoscopy after an average of 28.1 ± 8.7 months. The rate of advanced neoplasia at surveillance was not different between groups: no polyp group (13/551, 2.4%), LRA group (27/707, 3.8%), and low-risk SSP group (0/56, 0%). The LRA group exhibited a significantly higher rate of low- and high-risk polyps (47.5, 13.4%) than did the no polyp (35.6, 7.4%, p < .001, p = .001), but no significant differences to the low-risk SSP group (35.7, 7.1%, p = .117, p = .253), respectively.

CONCLUSIONS

Patients with low-risk SSPs were not at a higher risk of advanced neoplasia than LRA patients, even in the polyp-free group. We suggest that surveillance colonoscopy after the removal of low-risk SSPs is not required more often than for LRAs.

The association between Helicobacter pylori with nonalcoholic fatty liver disease assessed by controlled attenuation parameter and other metabolic factors

Aim

Existing studies have suggested an association between Helicobacter pylori (Hp) infection and nonalcoholic fatty liver disease (NAFLD). We investigated the relationship between Hp infection and NAFLD using controlled attenuation parameter (CAP) and other metabolic factors.

Method

We conducted a retrospective cohort study of apparently healthy individuals who underwent liver Fibroscan during health screening tests between January 2018 and December 2018. Diagnosis of Hp infection was based on a serum anti-Hp IgG antibody test and CAP values were used to diagnose NAFLD.

Results

Among the 1,784 subjects (mean age 55.3 years, 83.1% male), 708 (39.7%) subjects showed positive results of Hp serology. In the multivariate analysis, obesity (body mass index ≥25) (odds ratio [OR] 3.44, 95% confidence interval [CI] 2.75–4.29), triglyceride (OR 2.31, 95% CI 1.80–2.97), and the highest tertile of liver stiffness measurement (OR 2.08, 95% CI 1.59–2.71) were found to be associated with NAFLD, defined by CAP ≥248 dB/m, while Hp-seropositivity showed no association with NAFLD. Serum levels of HDL cholesterol significantly decreased in subjects with Hp-seropositivity compared to HP-seronegativity in both groups with and without NAFLD (P<0.001).

Conclusion

While Hp seropositivity was not associated with CAP-defined NAFLD, serum HDL cholesterol level were negatively associated with Hp-seropositivity in both groups with and without NAFLD. Further clinical and experimental studies are necessary to determine the association between Hp infection and NAFLD.

Graphene Nanocoating: High Quality and Stability upon Several Stressors

Titanium implants present 2 major drawbacks-namely, the long time needed for osseointegration and the lack of inherent antimicrobial properties. Surface modifications and coatings to improve biomaterials can lose their integrity and biological potential when exposed to stressful microenvironments. Graphene nanocoating (GN) can be deposited onto actual-size dental and orthopedic implants. It has antiadhesive properties and can enhance bone formation in vivo. However, its ability to maintain structural integrity and quality when challenged by biologically relevant stresses remains largely unknown. GN was produced by chemical vapor deposition and transferred to titanium via a polymer-assisted transfer technique. GN has high inertness and did not increase expression of inflammatory markers by macrophages, even in the presence of lipopolysaccharides. It kept high coverage at the top tercile of tapered dental implant collars after installation and removal from bone substitute and pig maxilla. It also resisted microbiologically influenced corrosion, and it maintained very high coverage area and quality after prolonged exposure to biofilms and their removal by different techniques. Our findings show that GN is unresponsive to harsh and inflammatory environments and that it maintains a promising level of structural integrity on the top tercile of dental implant collars, which is the area highly affected by biofilms during the onset of implant diseases. Our findings open the avenues for the clinical studies required for the use of GN in the development of implants that have higher osteogenic potential and are less prone to implant diseases.

Increasing changes in visceral adiposity is associated with higher risk for colorectal adenoma: Multilevel analysis in a prospective cohort

BACKGROUND AND AIM

While many studies demonstrated an association between visceral adiposity and colorectal adenoma (CRA), the effect of longitudinal changes in body fat composition on CRA is unclear. We investigated the longitudinal association between changes in visceral adiposity and CRA occurrence.

METHODS

Between 2006 and 2018, 732 (62.8%) of the 1165 subjects in a prospective cohort voluntarily underwent follow-up abdominal fat computed tomography and colonoscopy. We defined incident and recurrent CRA as adenoma detected at follow-up colonoscopy from negative and positive adenoma at baseline colonoscopy, respectively. Multilevel survival analysis examined the longitudinal association between changes in visceral fat and CRA.

RESULTS

During a median follow-up of 7.4 years, 400 (54.6%) subjects developed CRA. In multivariable analysis, increasing changes in visceral adipose tissue (VAT) area were associated with higher risk of incident adenoma (hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.00-1.46 for change per 10 cm² increase; HR 1.79, 95% CI 1.08-2.97 for highest vs lowest quartile, P values for trend = 0.045). Likewise, increasing changes in VAT area were independently associated with a higher risk of recurrent adenoma (HR 1.35, 95% CI 1.13-1.62 for change per 10 cm² increase; HR 1.62, 95% CI 1.04-2.52 for highest vs lowest quartile, P values for trend = 0.001). Changes in subcutaneous adipose tissue area were not independently associated with CRA.

CONCLUSION

Increasing changes in VAT area were longitudinally associated with a higher risk of incident and recurrent CRA, independent of risk factors, suggesting that visceral adiposity may be an important target in CRA prevention.

Longer Withdrawal Time Is More Important than Excellent Bowel Preparation in Colonoscopy of Adequate Bowel Preparation

BACKGROUND

Adequate bowel preparation is crucial for effective screening colonoscopy. However, it is unclear whether higher bowel preparation scores correspond to beneficial effects on the adenoma and polyp detection rate (ADR and PDR) in the adequate bowel preparation group.

AIMS

This study aimed to evaluate the effects of bowel preparation, according to the Boston Bowel Preparation Scale (BBPS), and colonoscopy withdrawal time (CWT) on ADR and PDR in the adequate bowel preparation group.

METHODS

Healthy examinees between 50 and 75 years old who underwent colonoscopy between September 2015 and August 2016 were included. BBPS scores, CWT, ADR, and PDR were reviewed retrospectively. Predictors of ADR and PDR were analyzed with a generalized linear mixed model.

RESULTS

A total of 5073 cases with adequate bowel preparation (BBPS ≥ 6) were analyzed. Examinees with good (BBPS = 6, 7) and excellent (BBPS = 8, 9) bowel preparation were 1898 (37.4%) and 3175 (62.6%), respectively. Both ADR and PDR were higher in the good bowel preparation group than in the excellent bowel preparation group (ADR 47.3% vs. 45.0%, P = 0.035; PDR 73.7% vs. 69.5%, P = 0.004, respectively). In the multivariate analysis, CWT, rather than BBPS, was significantly associated with both ADR (OR 1.04; 95% CI 1.02-1.06; P < 0.001) and PDR (OR 1.05; 95% CI 1.02-1.07; P = 0.002).

CONCLUSIONS

Both ADR and PDR were lower when bowel preparation was excellent rather than good. However, CWT, not BBPS, was significantly associated with ADR and PDR in the adequate bowel preparation group. Therefore, meticulous inspection is important for high-quality colonoscopy regardless of the BBPS score in examinees with adequate bowel preparation.

Astragalin Inhibits Nuclear Factor-κB Signaling in Human Colonic Epithelial Cells and Attenuates Experimental Colitis in Mice

Background/Aims

Astragalin (kaempferol-3-O-β-D-glucoside) is a flavonoid isolated from the leaves of persimmon or Rosa agrestis. Astragalin exhibits various anti-inflammatory properties; however, little is known about its therapeutic potential for inflammatory bowel disease (IBD). This study aims to investigate the anti-inflammatory effect of astragalin via blockade of the nuclear factor κB (NF-κB) signaling pathway in human colonic epithelial cells and a murine colitis model.

Methods

HCT-116 and HT-29 human colonic epithelial cells were pretreated with astragalin and stimulated with tumor necrosis factor-α (TNF-α). Cell viability was assessed by the MTS assay. Real-time reverse transcription polymerase chain reaction was used to analyze the messenger RNA expression of the inflammatory cytokines interleukin (IL)-6 and IL-8. The effect of astragalin on the NF-κB pathway was evaluated by Western blot analysis of inhibitor of NF-κB alpha (IκBα) phosphorylation/degradation and by electrophoretic mobility shift assay. Dextran sulfate sodium (DSS)-induced acute murine colitis model was used for in vivo experiments.

Results

Astragalin strongly suppressed the expression of proinflammatory cytokines in human colonic epithelial cells in a dose-dependent manner. Western blot analysis showed that astragalin inhibited IκBα phosphorylation/degradation. Additionally, astragalin reduced the DNA binding activity of NF-κB. Astragalin alleviated colon shortening and improved the pathologic scores in DSS-induced acute murine colitis model. Furthermore, astragalin reduced the level of phosphorylated IκBα and decreased the production of the inflammatory cytokines IL-6, IL-8, and TNF-α in the DSS-treated colon mucosa.

Conclusions

Astragalin exerted an anti-inflammatory effect through NF-κB pathway inhibition and attenuated murine colitis. Astragalin is thus a potential therapeutic agent for IBD.

Improved Accuracy in Optical Diagnosis of Colorectal Polyps Using Convolutional Neural Networks with Visual Explanations

BACKGROUND & AIMS

Narrow-band imaging (NBI) can be used to determine whether colorectal polyps are adenomatous or hyperplastic. We investigated whether an artificial intelligence (AI) system can increase the accuracy of characterizations of polyps by endoscopists of different skill levels.

METHODS

We developed convolutional neural networks (CNNs) for evaluation of diminutive colorectal polyps, based on efficient neural architecture searches via parameter sharing with augmentation using NBIs of diminutive (≤5 mm) polyps, collected from October 2015 through October 2017 at the Seoul National University Hospital, Healthcare System Gangnam Center (training set). We trained the CNN using images from 1100 adenomatous polyps and 1050 hyperplastic polyps from 1379 patients. We then tested the system using 300 images of 180 adenomatous polyps and 120 hyperplastic polyps, obtained from January 2018 to May 2019. We compared the accuracy of 22 endoscopists of different skill levels (7 novices, 4 experts, and 11 NBI-trained experts) vs the CNN in evaluation of images (adenomatous vs hyperplastic) from 180 adenomatous and 120 hyperplastic polyps. The endoscopists then evaluated the polyp images with knowledge of the CNN-processed results. We conducted mixed-effect logistic and linear regression analyses to determine the effects of AI assistance on the accuracy of analysis of diminutive colorectal polyps by endoscopists (primary outcome).

RESULTS

The CNN distinguished adenomatous vs hyperplastic diminutive polyps with 86.7% accuracy, based on histologic analysis as the reference standard. Endoscopists distinguished adenomatous vs hyperplastic diminutive polyps with 82.5% overall accuracy (novices, 73.8% accuracy; experts, 83.8% accuracy; and NBI-trained experts, 87.6% accuracy). With knowledge of the CNN-processed results, the overall accuracy of the endoscopists increased to 88.5% (P < .05). With knowledge of the CNN-processed results, the accuracy of novice endoscopists increased to 85.6% (P < .05). The CNN-processed results significantly reduced endoscopist time of diagnosis (from 3.92 to 3.37 seconds per polyp, P = .042).

CONCLUSIONS

We developed a CNN that significantly increases the accuracy of evaluation of diminutive colorectal polyps (as adenomatous vs hyperplastic) and reduces the time of diagnosis by endoscopists. This AI assistance system significantly increased the accuracy of analysis by novice endoscopists, who achieved near-expert levels of accuracy without extra training. The CNN assistance system can reduce the skill-level dependence of endoscopists and costs.

Clinical significance of perioperative EMT-CTC in rectal cancer patients receiving open/laparoscopic surgery

The objective of this study was to explore the clinical significance of perioperative CTCs (circulating tumor cells) counts and EMT-CTCs (epithelial-mesenchymal transition-CTCs) in rectal cancer patients. A total of 30 patients with rectal cancer who underwent radical resection of rectal cancer at the Guangxi Zhuang Autonomous Region People's hospital were enrolled. Five ml peripheral blood was withdrawn from 30 patients with rectal cancer before the operation and seven days after the operation and at the corresponding time also from 20 healthy volunteers. CanPatrol™ CTC detection technique was used to enrich and identify CTCs and IER3 expression simultaneously. We found out that the preoperative total CTCs were correlated with lymph node metastasis (p=0.008) and tumor size, and mixed CTCs were closely correlated with lymph node metastasis (p=0.009). The number of IER3-positive total CTCs and mesenchymal CTCs were statistically associated with tumor size, p=0.034 and 0.043, respectively. The number of CTCs varied significantly before and after the operation in all patients (p=0.049). There were significant differences in CTCs variations between the open operation group and the laparoscopic operation group. In the laparoscopic operation group, the average number of single-cell CTCs was 6.9 before operation and 3.5 after the operation (p=0.013). In the open operation group, the average number of single-cell CTCs was 5.9 before operation and 4.2 after the operation. To conclude, surgery is associated with a decrease of CTCs in rectal cancer patients, especially in patients receiving laparoscopic surgery. The number of CTCs before the operation in rectal cancer patients is related to the size of tumors and regional lymph node metastasis. CTCs detection and characterization may be useful for clinical staging and lymph node dissection during operation.

Inhibiting Corrosion of Biomedical-Grade Ti-6Al-4V Alloys with Graphene Nanocoating

The identification of metal ions and particles in the vicinity of failed implants has raised the concern that biomedical titanium alloys undergo corrosion in healthy and infected tissues. Various surface modifications and coatings have been investigated to prevent the deterioration and biocorrosion of titanium alloys but so far with limited success. Graphene is a cytocompatible atom-thick film made of carbon atoms. It has a very high surface area and can be deposited onto metal objects with complex shapes. As the carbon lattice has a very small pore size, graphene has promising impermeability capacity. Here, we show that graphene coating can effectively protect Ti-6Al-4V from corrosion. Graphene nanocoatings were produced on Ti-6Al-4V grade 5 and 23 discs and subjected to corrosive challenge (0.5M NaCl supplemented with 2-ppm fluoride, pH of 2.0) up to 30 d. The linear polarization resistance curves and electrochemical impedance spectroscopy analysis showed that the graphene-coated samples presented higher corrosion resistance and electrochemical stability at all time points. Moreover, the corrosion rate of the graphene-coated samples was very low and stable (~0.001 mm/y), whereas that of the uncoated controls increased up to 16 and 5 times for grade 5 and 23 (~0.091 mm/y) at the end point, respectively. The surface oxidation, degradation (e.g., crevice defects), and leaching of Ti, Al, and V ions observed in the uncoated controls were prevented by the graphene nanocoating. The Raman mappings confirmed that the graphene nanocoating presented high structural stability and resistance to mechanical stresses and chemical degradation, keeping >99% of coverage after corrosion challenge. Our findings open the avenues for the use of graphene as anticorrosion coatings for metal biomedical alloys and implantable devices.

Dietary threonine prevented stress-related mucosal diseases in rats

Stress-related mucosal disease (SRMD), or stress ulceration, is a group of conditions ranging from stress-related superficial gastric mucosal damage to deep gastric ulcers that are primarily correlated with mucosal ischemia, and pharmacologic interventions that optimize tissue perfusion or preserve defensive mucus aim to decrease the occurrence of conditions, such as gastric acidity, or enhance gastric defenses. However, the identification of multifactorial pathogenesis may be effective in preventing SMRD, and the use of stress prophylaxis is generally preferred. Since threonine is a component in the polymerization and synthesis of gastric mucin and possibly enhanced defense actions and lignin may provide structural support for defense and antioxidative function, we hypothesized that dietary intake of threonine and/or lignin can enhance defense against SRMD. The water immersion-restraint stress (WIRS) was used in rats and additional groups were pretreated with threonine alone or the combination of threonine and lignin. Based on gross and microscopic evaluations, threonine alone or the combination of threonine and lignin, a natural antioxidant, significantly reduced the development of SRMD (P < 0.05). According to molecular explorations, the levels of inflammatory mediators, such as interleukin (IL)-8, IL-6, IL-1β, inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ), all of which are mediators that play a significant role in controlling WIRS, significantly decreased in the groups pretreated with either threonine alone or the combination of threonine and lignin (P < 0.01). WIRS significantly increased apoptosis in the stomach. However, the apoptotic index significantly decreased with threonine pretreatment. According to periodic acid Schiff staining results, the expression of gastric mucin was significantly preserved in groups pretreated with threonine but remarkedly decreased in the WIRS group. The gastric heme oxygenase-1 levels significantly increased in the group treated with threonine. In conclusion, the dietary intake of threonine or the combination of threonine and lignin is effective in preventing SRMD.

There might be a distinctive clinical phenotype of constipation with non-cardiac chest pain which responds to combination laxatives: A retrospective, longitudinal symptom analysis

Proton pump inhibitor (PPI)-refractory non-cardiac chest pain (NCCP) is often resolved when constipation was relieved. This study aimed to investigate the clinical features of patients with both NCCP and constipated functional bowel disorders (FBD).Among 692 consecutive patients diagnosed with functional constipation or irritable bowel syndrome with constipation and underwent anorectal manometry (ARM) in our hospital, PPI-refractory NCCP was present in 37. The clinical course of various torso symptoms including NCCP and ARM findings were retrospectively evaluated.The mean age was lower in the NCCP than in the non-NCCP group (57.4 vs 61.3 years, respectively, P = .042). Back pain (16.2% vs 2.0%, P < .001) and sharp abdominal pain (13.5% vs 0.9%, P < .001) were more common in the NCCP group. Increased resting pressure (16.2% vs 6.9%, P = .036) and squeezing pressure (62.2% vs 50.7%, P = .049) of the anal sphincter, increased urgency volume (40.5% vs 23.2%, P = .004), and maximal volume (25.7% vs 15.0%, P = .032) for rectal sensation were more frequently observed in the NCCP group. After taking laxatives for 1 to 3 months, 81.1% of patients with NCCP reported improvement.Subjects with NCCP showed decreased rectal sensation more frequently at anorectal manometry. Majority of patients with NCCP reported improvement of symptom upon relief of constipation. Constipation might be a therapeutic target in patients with NCCP related to constipated functional bowel disorders.

Host nuclear factor erythroid 2-related factor-2 defense system determines the outcome of dextran sulfate sodium-induced colitis in mice

Administration of dextran sulfate sodium (DSS) in drinking water led to significant bout of colitis simulating ulcerative colitis of human. However, colitis usually developed 5 - 7 days after DSS administration. Therefore, we hypothesized host defense system might protect colitis up to 5 days of DSS administration. 2.5% DSS-induced colitis were administered to C57BL/6 mice and sequential measurements of pathology, cyclooxygenase-2 (COX-2), nuclear factor-κB (NF-κB), heme oxygenase-1 (HO-1), NADPH quinone oxidoreductase-1 (NQO1), γ-glutamylcysteine synthetase (γ-GCS), nuclear factor erythroid 2-related factor-2 (Nrf2), and keap1 were done at 2, 6, 12, 24, 48, 96, 120, and 168 hour of DSS administration, respectively. DSS-induced colitis was repeated in either COX-2^-/- or Nrf2^-/- mice. On serial pathological analysis, significant colitis was noted after 120 h of DSS administration, during which both activations of COX-2/NF-κB and HO-1/Nrf2 were noted. Nrf2 activations after keap1 inactivation led to significant increases in HO-1 after 168 hours of DSS administration, when NF-κB nuclear translocation was noted. Significantly attenuated colitis was noted in DSS-challenged COX-2^-/- mice, in which the levels of HO-1 were significantly decreased compared to DSS-challenged WT littermates (p < 0.01), while the levels of NQO1 were significantly increased. On DSS administration to Nrf2^-/- mice, colitis was significantly aggravated (p < 0.01), in which the expressions of COX-2 as well as expressions of HO-1 and γ-GCS were significantly increased (p < 0.01). Reciprocal activations of inflammatory and antioxidative defense signaling after DSS administration might be prerequisite to make intestinal homeostasis and host defense Nrf2 system can determine colitis.

Association Between Anxiety and Depression and Gastroesophageal Reflux Disease: Results From a Large Cross-sectional Study

Background/Aims

The different clinical manifestations of gastroesophageal reflux disease (GERD) may be influenced by associated psychological factors. We evaluated the psychological status (anxiety and depression) according to each subtype of GERD.

Methods

Subjects who underwent esophagogastroduodenoscopy and completed a symptom questionnaire between January 2008 and December 2011 were analyzed. The subjects were classified into the following groups: erosive reflux disease (ERD), non-erosive reflux disease (NERD), asymptomatic erosive esophagitis (AEE), and controls. Anxiety and depression were assessed using the State-Trait Anxiety Inventory and Beck Depression Inventory, respectively.

Results

We analyzed 19 099 subjects: 16 157 (84.6%), 176 (0.9%), 1398 (7.3%), and 1368 (7.2%) in the control, ERD, NERD, and AEE groups, respectively. Multiple multinomial logistic regression revealed a significant association of increased state (adjusted OR, 1.89; 95% CI, 1.53–2.33) and trait anxiety (adjusted OR, 1.78; 95% CI, 1.34–2.35) and depression (adjusted OR, 2.21; 95% CI, 1.75–2.80) with NERD. ERD group showed a significant association only with state anxiety (adjusted OR, 2.20; 95% CI, 1.27–3.81) and depression (adjusted OR, 2.23; 95% CI, 1.18–4.22). The AEE group, however, did not show any significant association with psychological factors.

Conclusion

This cross-sectional study revealed that anxiety and depression levels were significantly higher in subjects with GERD (notably in the NERD) than in controls.

Long-term outcome of group D patients with negative serum anti-Helicobacter pylori antibody and positive serum pepsinogen test in healthy Koreans

OBJECTIVE

The aim of this study was to assess the clinical characteristics and long-term outcomes of group D patients (negative H. pylori antibodies and positive pepsinogen level).

METHODS

Group D patients were divided into two groups, that is, the limited endoscopic atrophic gastritis (EAG) group with EAG confined to the antrum and angle (C1 and C2) and the advanced EAG group with gastric body-involved EAG (C3 to O3). We compared the progression of precursor lesions and the occurrence of gastric neoplasms between the two groups.

RESULTS

Among 107 group D patients, the advanced EAG group (n = 60) was elder and had a lower pepsinogen I level and a lower pepsinogen I to II ratio (PGI/II) than the limited EAG group (n = 47). Among the 52 patients who underwent a follow-up endoscopy, three gastric neoplasms were detected (one in the limited and two in the advanced EAG groups). During a median follow-up of 44 months, 10 (43.5%) patients in the limited and 13 (52.0%) in the advanced EAG groups showed EAG progression or newly occurred intestinal metaplasia. A family history of GC (odds ratio [OR] 44.974, 95% confidence interval [CI] 1.360-1487.087), a lower PGI/II (OR 0.247, 95% CI 0.085-0.717) and a longer follow-up duration (OR 1.832, 95% CI 1.200-2.796) increased the risk of progression.

CONCLUSION

A family history of GC and low baseline PGI/II were independently associated with an increased risk of progression of precursor lesions of GC.

Visceral obesity as a risk factor for colorectal adenoma occurrence in surveillance colonoscopy

BACKGROUND AND AIMS

The aim of this study was to examine the prospective association between visceral obesity and the incidence and recurrence of colorectal adenoma.

METHODS

We conducted a cohort study involving 2244 participants between 2006 and 2007. The study participants were prospectively followed until 2014 according to the initial colonoscopy and histopathology findings. Incident and recurrent colorectal adenoma groups were defined as individuals with a positive follow-up colonoscopy result from the normal results and adenoma groups, respectively, at the baseline colonoscopy.

RESULTS

Among the 1163 patients (51.8%) who received a follow-up colonoscopy, 509 (43.8%) and 654 (56.2%) were grouped into the normal and adenoma cohorts. Colorectal adenomas occurred in 592 patients (50.9%) during the median period of 43 months, with an incident adenoma prevalence of 39.1% and a recurrent adenoma prevalence of 60.1%. An increase in the visceral adipose tissue (VAT) area was associated with a higher incidence of adenoma (highest quintile vs lowest quintile of the VAT hazard ratios [HRs], 2.16; 95% confidence interval [CI], 1.26-3.71; HR 1.32 [per 1-standard deviation]; 95% CI, 1.10-1.60) in the multivariable analysis. Increases in body mass index and waist circumference were associated with recurrent adenomas (HR 1.33 [per 1 kg/m²], 95% CI, 1.18-1.46; HR 1.04 [per 1 cm], 95% CI, 1.01-1.07, respectively) in the multivariate analysis.

CONCLUSION

A higher VAT area was dose-dependently associated with a higher risk of incident adenoma. Furthermore, increases in body mass index and waist circumference as surrogate markers of abdominal obesity were associated with a higher risk of recurrent adenoma.

Modified Floating Electrode-Based Sensors for the Quantitative Monitoring of Drug Effects on Cytokine Levels Related with Inflammatory Bowel Diseases

Modified floating electrode-based sensors were developed to quantitatively monitor the levels of tumor necrosis factor α (TNF-α), a pro-inflammatory cytokine related with inflammatory bowel disease (IBD), and to evaluate the effect of drugs on the cytokine levels. Here, antibodies (anti-TNF-α) were immobilized on the floating electrodes of carbon nanotube devices, enabling selective and real-time detection of TNF-α among various cytokines linked to IBD. This sensor was able to measure the concentrations of TNF-α with a detection limit of 1 pg/L, allowing the quantitative estimation of TNF-α secretion from mouse macrophage Raw 264.7 cells stimulated by lipopolysaccharides (LPS). Notably, this method also allowed us to monitor the anti-inflammatory effect of a drug, lupeol, on the activation of the LPS-induced nuclear factor κB signaling in Raw 264.7 cells. These results indicate that our novel TNF sensor can be a versatile tool for biomedical research and clinical applications such as screening drug effects and monitoring inflammation levels.

Risk Factors for Vitamin D, Zinc, and Selenium Deficiencies in Korean Patients with Inflammatory Bowel Disease

Background/Aims

Studies on the micronutrient status of Asian patients with inflammatory bowel disease (IBD) are scarce. We evaluated the prevalence of micronutrient deficiency and verified the risk factors for micronutrient deficiency in Korean patients with IBD.

Methods

We measured the serum levels of 25-hydroxyvitamin D3 [25-(OH)D], zinc, and selenium to analyze the clinical risk factors for micronutrient levels below the reference values. In addition, we compared the 25-(OH)D levels of patients with IBD to those of age- and sex-matched healthy controls.

Results

Among the 83 patients, 74 (89.2%) had suboptimal serum 25-(OH)D levels. The mean plasma 25-(OH)D level in patients with IBD was significantly reduced compared to that of the healthy controls (12.3±6.2 ng/mL vs 20.0±6.7 ng/mL; p<0.001). The proportions of patients with lower serum zinc and selenium levels were 39.0% and 30.9%, respectively. Female sex (p=0.012) and Crohn’s disease (p=0.012) were associated with vitamin D deficiency. Patients younger than 40 years were at increased risk for zinc deficiency (p=0.045). Female sex (p=0.015) and low serum albumin level (<3.3 g/dL) (p=0.047) were risk factors for selenium deficiency.

Conclusions

Many Korean patients with IBD have vitamin D, zinc, and selenium deficiencies, suggesting the necessity for monitoring levels of these micronutrients.

Comparison of the Efficacies of Parenteral Iron Sucrose and Oral Iron Sulfate for Anemic Patients with Inflammatory Bowel Disease in Korea

BACKGROUND/AIMS

The optimal route for iron administration in anemic patients with inflammatory bowel disease (IBD) has not been determined. The aim of this study was to compare the efficacies of parenteral and oral iron therapy in IBD patients in Korea.

METHODS

A retrospective multicenter study was performed. Patients who had been administered parenteral iron were matched to the controls with oral iron at a 1:1 ratio according to age, sex, and type of IBD.

RESULTS

Patients that received parenteral iron exhibited increases in hemoglobin levels of ≥20% from the baseline at lower doses and in shorter durations (p=0.034 and p=0.046, respectively). In the multivariate analysis, parenteral iron therapy appeared to be more efficient than oral iron therapy, but this difference was not statistically significant (hazard ratio [HR], 1.552; 95% confidence interval [CI], 0.844 to 2.851; p=0.157). Patients with ulcerative colitis responded better to iron therapy than those with Crohn's disease (HR, 3.415; 95% CI, 1.808 to 6.450; p<0.001). Patients with an initial hemoglobin level of 10 g/dL or higher responded poorly to iron therapy (HR, 0.345; 95% CI, 0.177 to 0.671; p=0.002).

CONCLUSIONS

Parenteral iron therapy appears to be more efficient than oral iron therapy. Physicians should focus on the iron deficiency of IBD patients and consider parenteral iron supplements in appropriate patient groups.

Colon Capsule Endoscopy: Where Are We and Where Are We Going

Colon capsule endoscopy (CCE) is a noninvasive technique for diagnostic imaging of the colon. It does not require air inflation or sedation and allows minimally invasive and painless colonic evaluation. The role of CCE is rapidly evolving; for example, for colorectal screening (colorectal cancer [CRC]) in average-risk patients, in patients with an incomplete colonoscopy, in patients refusing a conventional colonoscopy, and in patients with contraindications for conventional colonoscopy. In this paper, we comprehensively review the technical characteristics and procedure of CCE and compare CCE with conventional methods such as conventional colonoscopy or computed tomographic colonography. Future expansion of CCE in the area of CRC screening for the surveillance of polyps and adenomatous lesions and for assessment of inflammatory bowel disease is also discussed.

Patients with perianal Crohn's disease have poor disease outcomes after primary bowel resection

BACKGROUND AND AIM

The presence of perianal disease in Crohn's disease patients is one of the factors of postoperative recurrence. The aim of this study is to evaluate long-term prognosis of perianal Crohn's disease patients in Asian.

METHODS

Patients with Crohn's disease who had undergone surgical bowel resection were divided into two groups according to the presence of perianal lesion. We monitored the occurrences of abdominal and/or perianal reoperation and readmission due to disease flare-up.

RESULTS

The 132 patients included in the study were divided into 2 groups, those with perianal disease (45 patients, 34.1%) and those without perianal disease (87 patients, 65.9%). Patients with perianal disease was younger in age (33.8 years versus 39.8 years, p = 0.015) and had been diagnosed as CD at a younger age (21.9 years versus 28.6 years, p = 0.005) than patients without perianal disease. Patients with perianal disease showed more extra-intestinal manifestation than patients without perianal disease (8 versus 3, p = 0.008). Reoperation was required in 46 (44.8%) patients during the follow-up period. The presence of perianal disease independently increased the risk of reoperation [hazard ratio (HR), 3.112; confidence interval (CI), 1.707-5.675]. Furthermore, patients with perianal disease had increasing risks of abdominal reoperation (HR 1.978; 95% CI, 1.034-3.784).

CONCLUSIONS

Patients with Crohn's disease and perianal lesions had a higher risk of reoperation. Considering these findings, physicians should consider aggressive and early top down therapy for patients with perianal Crohn's disease.

Reconstruction of atmospheric soot history in inland regions from lake sediments over the past 150 years

Historical reconstruction of atmospheric black carbon (BC, in the form of char and soot) is still constrained for inland areas. Here we determined and compared the past 150-yr records of BC and polycyclic aromatic compounds (PACs) in sediments from two representative lakes, Huguangyan (HGY) and Chaohu (CH), in eastern China. HGY only receives atmospheric deposition while CH is influenced by riverine input. BC, char, and soot have similar vertical concentration profiles as PACs in both lakes. Abrupt increases in concentrations and mass accumulation rates (MARs) of soot have mainly occurred since ~1950, the establishment of the People’s Republic of China, when energy usage changed to more fossil fuel contributions reflected by the variations in the concentration ratios of char/soot and individual PACs. In HGY, soot MARs increased by ~7.7 times in the period 1980–2012 relative to the period 1850–1950. Similar increases (~6.7 times) were observed in CH. The increase in soot MARs is also in line with the emission inventory records in the literature and the fact that the submicrometer-sized soot particles can be dispersed regionally. The study provides an alternative method to reconstruct the atmospheric soot history in populated inland areas.

The expression of osteopontin in breast cancer tissue and its relationship with p21ras and CD44V6 expression

OBJECTIVE

This study aimed to investigate the expression of osteopontin (OPN), p2lras, and CD44V6 in breast cancer tissues, and to analyze the relationships between their expression and a patient's clinicopathological characteristics and five-year survival rate.

MATERIALS AND METHODS

Streptavidin-peroxidase immunohistochemistry was used to detect the expression of OPN, p2lras, and CD44V6 in tissue samples from 96 breast cancer patients, and the multivariate Cox proportional hazards model (mCOX-PHM) was used to analyze the factors that affect prognosis.

RESULTS

Among the 96 breast cancer patients studied, positive staining for OPN, CD44V6, and p21ras was observed in 54.2%, 58.3%, and 43.8% of samples, respectively. The expression of OPN and CD44V6 were positively correlated (r = 0.58), and the expression of OPN and p21ras were also positively correlated (r = 0.25). Coexpression OPN, CD44V6, and p21ras was negatively correlated with a patient's five-year survival rate (p < 0.05). Kaplan-Meier analysis indicated that a patient without OPN, CD44V6, or p21ras expression had an improved survival (p < 0.05). Results from the mCOX-PHM analysis indicated that CD44V6 expression, the degree of tumor differentiation, and lymph node metastasis were all independent factors that indicate prognosis. The combined detection of OPN, CD44V6, and p21ras could contribute to a more accurate assessment of the biological behavior of breast cancers, and could help to indicate the prognosis of breast cancer patients.

Bio-inspired terpolymers containing dopamine, cations and MPC: a versatile platform to construct a recycle antibacterial and antifouling surface

A new kind of bio-inspired terpolymer was synthesized by a conventional free radical terpolymerization of dopamine methacrylamide (DMA), 2-(dimethylamino)-ethyl methacrylate (DMAEMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) with azobisisobutyronitrile (AIBN) as an initiator. DMA consists of a biomimetic adhesive side chain covalently linked to a polymerizable methacrylate monomer. 1H NMR and gel permeation chromatography confirmed the successful synthesis of P(DMA-co-MPC-co-DMAEMA). The terpolymer could self-assemble on the macroscopic planar substrates with DMA as an anchor. After being quaternized by 1-bromo-heptane, terpolymers of P(DMA-co-MPC-co-DMAEMA+) with bactericidal function were obtained. The self-assembly terpolymer on the substrate was confirmed by X-ray photoelectron spectroscopy, water contact angle, spectroscopic ellipsometry and atomic force microscopy. The hydrophilicity and antifouling properties of the self-assembly coating increased greatly against bacteria, protein and cells with the increase of MPC content. As the existence of bactericidal cations for electrostatic targeting of bacteria as well as membrane lysis, the terpolymer coating showed excellent bactericidal function against E. coli and S. aureus. Biofilm inhibition assay showed that terpolymer coating was very efficient to resist bacterial adhesion and biofilm formation in a nutrient environment. Bacteria could be continuously "captured" and killed by the terpolymer coating, and then bacteria corpse was released into the solution. Importantly, this work provides a versatile strategy for the fabrication of a recycle antibacterial and antifouling surface to modify biomaterials.

Elemental carbon and polycyclic aromatic compounds in a 150-year sediment core from Lake Qinghai, Tibetan Plateau, China: influence of regional and local sources and transport pathways

Elemental carbon (EC) and polycyclic aromatic compounds (PACs) are potential proxies for the reconstruction of change in human activities and the origin of air masses in historic times. In this study, the historic deposition of char and soot (the two subtypes of EC) and PACs in a 150-year sediment core from different topographic subbasins of Lake Qinghai on the Qinghai Tibetan Plateau (QTP) were reconstructed. The objective was to explore how the variations in the concentrations of EC and PACs, in the ratios of char to soot and of oxygenated polycyclic aromatic hydrocarbons (OPAHs) to parent PAHs, and in the composition of the PAC mixtures reflect historical changes in climate and human activity and the origin of air masses arriving at the QTP. The deposition fluxes of soot in the different subbasins were similar, averaging 0.18 (range of 0.15-0.25) and 0.16 (0.13-0.23) g m(-2) year(-1), respectively, but they varied for char (averaging 0.11 and 0.22 g m(-2) year(-1), respectively), suggesting ubiquitous atmospheric deposition of soot and local river inputs of char. The different vertical distributions of the char/soot ratios in the different subbasins can be interpreted in terms of the different transport mechanisms of char and soot. An abrupt increase in soot concentrations since 1980 coincides with results from the QTP ice cores that were interpreted to be indicative of soot transport from South Asia. Similar concentration patterns of PAHs with soot and 9,10-anthraquinone/anthracene (9,10-AQ/ANT) ratios all >2.0 suggest regional PAC sources. Increasing PAH/soot ratios and decreasing 9,10-AQ/ANT ratios since the beginning of the 1970s indicate increasing local emissions. The historical trends of these diagnostic ratios indicate an increase in the fossil-fuel contribution since the beginning of the 1970s. The increase of perylene concentrations with increasing core depth and the ratio of perylene to its penta-aromatic isomers indicate that perylene originates mainly from in situ biogenic diagenesis. We demonstrate that the concentrations of EC, char, soot, and PACs in sediments can be used to reconstruct local, regional, and remote sources and transport pathways of pollutants to the QTP.

Stronger association of polycyclic aromatic hydrocarbons with soot than with char in soils and sediments

The knowledge of the association of polycyclic aromatic hydrocarbons (PAHs) with organic matter and carbonaceous materials is critical for a better understanding of their environmental transport, fate, and toxicological effects. Extensive studies have been done with regard to the relationship of PAHs with total organic carbon (TOC) and elemental carbon (EC) in different environmental matrices. The relationship between PAHs and the two subtypes of EC, char (combustion residues) and soot (produced via gas-to-particle conversion) also has been tested in field and laboratory experiments using reference materials. However, a direct comparison of associations of PAHs between with char and with soot in real environmental matrices has to our knowledge not yet been reported because of a lack of methodology to differentiate them. In this study, char and soot were measured using the IMPROVE method to test their associations with 12 EPA priority PAHs measured in topsoil samples (N=22, top 10 cm) collected from the Guanzhong Plain and in surface sediment samples (N=32, top 5 cm) from the Wei River (central China). In both soils and sediments, ∑12PAHs were more strongly associated with soot than with char, mainly due to the fact that soot and PAHs were produced in the same gas phase during combustion, had a strong affinity for each other, and were transported and deposited together, while char, the combustion residue, was transported differently to PAHs due to its large particle size. Stronger correlations between PAHs and the different carbon fractions (TOC, soot, and char) in sediments than in soils were observed, which is associated with the redistribution of PAHs among the organic matter pools in water because of the processes during soil erosion and sedimentation in the river.

Recent chemotherapy reduces the maximum-standardized uptake value of 18F-fluoro-deoxyglucose positron emission tomography in colorectal cancer

BACKGROUND/AIMS

The aim of this study was to evaluate the influence of recent chemotherapy on the patterns of the maximum-standardized uptake value (M-SUV) and sensitivity of (18)F-fluoro-deoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) in colorectal cancer.

METHODS

We retrospectively analyzed the FDG-PET/CT of 509 patients who underwent surgery for colorectal cancer. Subgroup analysis was performed according to chemotherapy status; 401 patients were not treated with chemotherapy and 108 patients were treated with chemotherapy within 6 months prior to surgery. Pathologic analysis of the surgical specimen was used as the gold standard.

RESULTS

The M-SUV was significantly lower in patients treated with chemotherapy than in those not treated with chemotherapy in pathologically confirmed same stages of disease. The difference in the sensitivity of the M-SUV according to chemotherapy status was greatest using a cutoff M-SUV value of 6.4 (p<0.001). The longest diameter of the primary tumor was the most important factor that correlated with M-SUV of the primary tumor irrespective of the chemotherapy effect (p<0.001). The M-SUV of the primary tumor was not an independent predictor of lymph node metastasis in colorectal cancer.

CONCLUSIONS

The results indicate that the M-SUV of FDG-PET/CT should be interpreted in the context of concurrent chemotherapy.

Long-term oncologic outcomes of endoscopic stenting as a bridge to surgery for malignant colonic obstruction: comparison with emergency surgery

BACKGROUND

Self-expandable metallic stents (SEMS) are now regarded as an effective and safe intervention for malignant colorectal obstruction (MCO). However, manipulation of the tumor might lead to the spillage of tumor cells and result in distant metastases. We aimed to compare the long-term oncologic outcomes of SEMS as a bridge to surgery with those of emergency surgery for MCO.

METHODS

Between June 2005 and December 2011, 60 patients who underwent elective curative resection after endoscopic SEMS insertion were included in the "SEMS group". The SEMS group was matched to 180 patients who underwent emergency curative surgery for MCO during the same period ["Emergency surgery (ES) group"]. The clinicopathologic characteristics, recurrence-free survival (RFS), and overall survival (OS) were compared between the two groups.

RESULTS

There were no significant differences in demographics, tumor stage, location, and histology between the SEMS group and the ES group. The median follow-up times were 41.4 months (IQR, 22.2-60.0 months) for the SEMS group and 45.0 months (IQR, 20.9-68.1 months) for the ES group. The proportions of patients who received postoperative adjuvant chemotherapy were comparable (SEMS group vs. ES group, 68.3 % vs. 77.8 %; P = 0.210). The long-term prognosis did not significantly differ between two groups in either the 5-year RFS rate (79.6 % vs. 70.2 %; P = 0.218) or the 5-year OS rate (97.8 % vs. 94.3 %; P = 0.469).

CONCLUSIONS

Long-term oncologic outcomes of SEMS insertion as a bridge to surgery were comparable to those of primary curative surgery.

Endoscopic removal of a migrated coil after embolization of a splenic pseudoaneurysm: a case report

Splenic artery pseudoaneurysms can be caused by pancreatitis, trauma, or operation. Traditionally, the condition has been managed through surgery; however, nowadays, transcatheter arterial embolization is performed safely and effectively. Nevertheless, several complications of pseudoaneurysm embolization have been reported, including coil migration. Herein, we report a case of migration of the coil into the jejunal lumen after transcatheter arterial embolization of a splenic artery pseudoaneurysm. The migrated coil was successfully removed by performing endoscopic intervention.

Nonsteroidal anti-inflammatory drugs (NSAID) sparing effects of glucosamine hydrochloride through N-glycosylation inhibition; strategy to rescue stomach from NSAID damage

Gastrointestinal or cardiovascular complications limit nonsteroidal anti-inflammatory drugs (NSAID) prescription. Glucosamine hydrochloride (GS-HCl) alternatively chosen, but debates still exist in its clinical efficiency. COX-2 instability through inhibiting COX-2 N-glycosylation of GS-HCl raised the possibility of NSAID sparing effect. Study was done to determine whether combination treatment of glucosamine and NSAID contributes to gastric safety through NSAID sparing effect. IEC-6 cells were stimulated with TNF-α and compared the expressions of inflammatory mediators after indomethacin alone or combination of indomethacin and GS-HCl by Western blotting and RT-PCR. C57BL/6 mice injected with type II collagen to induce arthritis were treated with indomethacin alone or combination of reduced dose of indomethacin and GS-HCl after 3 weeks. TNF-α increased the expression of COX-2, iNOS and inflammatory cytokines, but GS-HCl significantly attenuated TNF-α-induced COX-2 expression. Decreased COX-2 after GS-HCl was caused by N-glycosylation inhibition as much as tunicamycin. Combination of reduced dose of indomethacin and GS-HCl significantly reduced the expressions of ICAM-1, VCAM-1, IL-8, IL-1β, MMP-2, MMP-7, MMP-9, and MMP-11 mRNA as well as NF-κB activation better than high dose indomethacin alone. These NSAID sparing effect of GS-HCl was further proven in collagen-induced arthritis model. Combination of GS-HCl and 2.5 mg/kg indomethacin showed significant protection from gastric damages as well as efficacious anti-arthritic effect. Taken together, COX-2 N-glycosylation inhibition by GS-HCl led to indomethacin sparing effects, based on which combination of GS-HCl and reduced dose of NSAID can provide the strategy to secure stomach from NSAID-induced gastric damage as well as excellent anti-arthritic effects.

Diagnostic efficacy of gadoxetic acid-enhanced MRI for the detection and characterisation of liver metastases: comparison with multidetector-row CT

OBJECTIVES

We compared the diagnostic performance of gadoxetic acid-enhanced MRI and 16-slice multidetector CT (MDCT) with respect to their abilities to detect hepatic metastases and differentiate hepatic metastases from hepatic cysts and haemangiomas.

METHODS

67 patients with 110 liver metastases (size 0.3-2.5 cm), 33 haemangiomas (size 0.5-1.5 cm) and 17 cysts (size 0.3-1.0 cm) underwent 4-phase MDCT and gadoxetic acid-enhanced MRI, including early dynamic phases, post-contrast T(2) weighted turbo spin echo sequences and 20 min hepatocyte-selective phases. Two observers independently analysed each image in random order. Sensitivity and diagnostic accuracy for lesion detection and differentiation for MDCT and gadoxetic acid-enhanced MRI were calculated using receiver operating characteristic analysis.

RESULTS

For both observers, the Az values of gadoxetic acid-enhanced MRI (mean, 0.982 and 0.981) were significantly higher than the Az values of MDCT (mean, 0.839 and 0.892) (p<0.05) for the detection of metastases and for the differentiation of metastases from haemangiomas and cysts. Sensitivities of gadoxetic acid-enhanced MRI with regard to the detection and characterisation of liver metastases (mean, 96.9% and 96.0%) were significantly higher than those of MDCT (mean, 78.7% and 75.0%) (p<0.05).

CONCLUSION

Gadoxetic acid-enhanced MRI showed higher diagnostic accuracy and sensitivity than did MDCT for the detection of hepatic metastases and for the differentiation between hepatic metastases and hepatic haemangiomas or cysts.

Characteristics and source apportionment of PM1 emissions at a roadside station

The mass concentrations of PM(1) (particles less than 1.0 μm in aerodynamic diameter), organic carbon (OC), elemental carbon (EC), water-soluble ions, and up to 25 elements were reported for 24h aerosol samples collected every sixth day at a roadside sampling station in Hong Kong from October 2004 to September 2005. Annual average PM(1) mass concentration was 44.5 ± 19.5 μg m(-3). EC, OM (organic matter, OC × 1.2), and SO(4)(=) were the dominant components, accounting for ∼ 36%, ∼ 26%, and ∼ 24% of PM(1), respectively. Other components, i.e., NO(3)(-), NH(4)(+), geological material, trace elements and unidentified material, comprised the remaining ∼ 14%. Annual average OC/EC ratio (0.6 ± 0.3) was low, indicating that primary vehicle exhaust was the major source of carbonaceous aerosols. The seasonal variations of pollutants were due to gas-particle partitioning processes or a change in air mass rather than secondary aerosol produced locally. Vehicle exhaust, secondary aerosols, and waste incinerator/biomass burning were dominant air pollution sources, accounting for ∼ 38%, ∼ 22% and ∼ 16% of PM(1), respectively. Pollution episodes during summer (May-August) which were frequently accompanied by tropical storms or typhoons were dominated by vehicle emissions. During winter (November-February) pollution episodes coincided with northeasterly monsoons were characterized by secondary aerosols and incinerator/biomass burning emissions.

Comparison of elemental carbon in lake sediments measured by three different methods and 150-year pollution history in Eastern China

Concentrations of elemental carbon (EC) were measured in a 150 yr sediment record collected from Lake Chaohu in Anhui Province, eastern China, using three different thermal analytical methods: IMPROVE_A thermal optical reflectance (TOR), STN_thermal optical transmittance (TOT), and chemothermal oxidation (CTO). Distribution patterns for EC concentrations are different among the three methods, most likely due to the operational definition of EC and different temperature treatments prescribed for each method. However, similar profiles were found for high-temperature EC fractions among different methods. Historical soot(TOR) (high-temperature EC fractions measured by the IMPROVE_A TOR method) from Lake Chaohu exhibited stable low concentrations prior to the late 1970s and a sharp increase thereafter, corresponding well with the rapid industrialization of China in the last three decades. This may suggest that high-temperature thermal protocols are suitable for differentiating between soot and other carbon fractions. A similar soot(TOR) record was also obtained from Lake Taihu (~200 km away), suggesting a regional source of soot. The ratio of char(TOR) (low-temperature EC fraction measured by the IMPROVE_A TOR method, after correction for pyrolysis) to soot(TOR) in Lake Chaohu shows an overall decreasing trend, consistent with gradual changes in fuel use from wood burning to increasing fossil fuel combustions. Average higher char(TOR)/soot(TOR) was observed in Lake Taihu than in Lake Chaohu in the past 150 years, consistent with the longer and more extensive industrialization around the Taihu region.

The effect of acidification on the determination of elemental carbon, char-, and soot-elemental carbon in soils and sediments

We studied the influence of acid pretreatment on the effective distinction between elemental carbon (EC) and organic carbon (OC), and between char-EC and soot-EC. Though widely employed in the pretreatment of soils and sediments for EC quantification, the use of HCl, HF, and HNO(3) could decrease soot thermal stability as acid remains, leading to an underestimation of soot-EC by thermal methods. We compared thermal optical reflectance (TOR) measurements of EC concentrations in char reference materials and in lacustrine and marine sediments following pretreatment with various acids. The results showed that pretreatment with 2M HCl, concentrated HNO(3), 7 M HNO(3), and 1 M HNO(3) did not result in EC oxidation. However, hot concentrated HNO(3) oxidized EC significantly, leading to lower concentrations of EC, char-EC and soot-EC. By comparing the removal of potentially interfering materials, which contain little fire-derived carbon, with different acid pretreatments, we recommend the HCl-HF-HCl and concentrated (not hot) HNO(3)-HF-HCl pretreatments for the determination of EC, char-EC, and soot-EC in soils and sediments using the TOR method.

Detection of small hepatocellular carcinoma: comparison of conventional gadolinium-enhanced MRI with gadolinium-enhanced MRI after the administration of ferucarbotran

We compared the diagnostic efficacy of gadolinium (Gd)-enhanced MRI with that of Gd-enhanced MRI after administration of ferucarbotran for revealing small hypervascular hepatocellular carcinomas (HCCs). 24 patients with 34 HCCs (ranging in size from 0.6-2.0 cm) underwent Gd-enhanced three-dimensional dynamic MRI followed, after an interval of 5-11 days (mean, 7 days), by Gd-enhanced three-dimensional dynamic MRI after administration of ferucarbotran. The two Gd-enhanced arterial-phase MRI scans were compared quantitatively by measuring the tumour-liver contrast-to-noise ratio (CNR) and qualitatively by evaluating the tumour-liver contrast using matched-pairs analysis. The tumour-liver CNR with Gd-enhanced arterial-phase imaging after ferucarbotran (250.3 +/- 103.7) was higher than that with Gd-enhanced arterial-phase imaging (221.1 +/- 96.1) (p < 0.001). Matched-pairs analysis indicated that, for three lesions, the relative tumour-liver contrast was slightly better with Gd-enhanced arterial-phase imaging after ferucarbotran than with conventional Gd-enhanced arterial-phase imaging; however, in the case of the remaining 31 lesions, the two images were equivalent. We concluded that, although Gd-enhanced arterial-phase imaging after ferucarbotran results in better tumour-liver CNR than Gd-enhanced arterial-phase imaging, the ability of the two techniques to reveal small hypervascular HCCs is the same.