Nickel-rich layered lithium transition-metal oxides, LiNi(1-x)M(x)O(2) (M = transition metal), have been under intense investigation as high-energy cathode materials for rechargeable lithium ...batteries because of their high specific capacity and relatively low cost. However, the commercial deployment of nickel-rich oxides has been severely hindered by their intrinsic poor thermal stability at the fully charged state and insufficient cycle life, especially at elevated temperatures. Here, we report a nickel-rich lithium transition-metal oxide with a very high capacity (215 mA h g(-1)), where the nickel concentration decreases linearly whereas the manganese concentration increases linearly from the centre to the outer layer of each particle. Using this nano-functional full-gradient approach, we are able to harness the high energy density of the nickel-rich core and the high thermal stability and long life of the manganese-rich outer layers. Moreover, the micrometre-size secondary particles of this cathode material are composed of aligned needle-like nanosize primary particles, resulting in a high rate capability. The experimental results suggest that this nano-functional full-gradient cathode material is promising for applications that require high energy, long calendar life and excellent abuse tolerance such as electric vehicles.
We propose a feasibility of Co-free Ni-rich Li(Ni1–x Mn x )O2 layer compound. Li(Ni1–x Mn x )O2 (0.1 ≤ x ≤ 0.5) have been synthesized by a coprecipitation method. Rietveld refinement of X-ray ...diffraction and microscopic studies reveal dense and spherical secondary particles of highly crystalline phase with low cation mixing over the whole compositions, implying successful optimization of synthetic conditions. Electrochemical test results indicated that the Co-free materials delivered high capacity with excellent capacity retention and reasonable rate capability. In particular, Li(Ni0.9Mn0.1)O2, which possesses the lowest cation mixing in the Li layers among samples, exhibited exceptionally high rate capacity (approximately 149 mAh g–1 at 10 C rate) at 25 °C and high discharge capacity upon cycling under a severe condition, in the voltage range of 2.7–4.5 V at 55 °C. The cation mixing in Li(Ni0.9Mn0.1)O2 increased slightly even after the extensive cycling at the elevated temperature, which is ascribed to the structural integrity induced from the optimized synthetic condition using the coprecipitation.
We aimed to develop a computer-aided diagnostic system (CAD) for predicting colorectal polyp histology using deep-learning technology and to validate its performance. Near-focus narrow-band imaging ...(NBI) pictures of colorectal polyps were retrieved from the database of our institution. Of these, 12480 image patches of 624 polyps were used as a training set to develop the CAD. The CAD performance was validated with two test datasets of 545 polyps. Polyps were classified into three histological groups: serrated polyp (SP), benign adenoma (BA)/mucosal or superficial submucosal cancer (MSMC), and deep submucosal cancer (DSMC). The overall kappa value measuring the agreement between the true polyp histology and the expected histology by the CAD was 0.614-0.642, which was higher than that of trainees (n = 6, endoscopists with experience of 100 NBI colonoscopies in <6 months; 0.368-0.401) and almost comparable with that of the experts (n = 3, endoscopists with experience of 2,500 NBI colonoscopies in ≥5 years) (0.649-0.735). The areas under the receiver operating curves for CAD were 0.93-0.95, 0.86-0.89, and 0.89-0.91 for SP, BA/MSMC, and DSMC, respectively. The overall diagnostic accuracy of the CAD was 81.3-82.4%, which was significantly higher than that of the trainees (63.8-71.8%, P < 0.01) and comparable with that of experts (82.4-87.3%). The kappa value and diagnostic accuracies of the trainees improved with CAD assistance: that is, the kappa value increased from 0.368 to 0.655, and the overall diagnostic accuracy increased from 63.8-71.8% to 82.7-84.2%. CAD using a deep-learning model can accurately assess polyp histology and may facilitate the diagnosis of colorectal polyps by endoscopists.
Low-volume bowel preparation solutions, including 1-L polyethylene glycol plus ascorbate (PEG-A), have been developed to improve tolerability. The oral sodium sulfate tablet (OST) is a new agent with ...simethicone as a preloaded component. We investigated the efficacy, safety, and tolerability of OST compared to 1-L PEG-A.
A single-center, prospective, controlled study was performed with randomization into the OST (group A) and 1-L PEG-A (group B) groups. Bowel preparation efficacy was assessed on the Boston Bowel Preparation Scale (BBPS) and Bubble Scale. Safety and tolerability were evaluated using a questionnaire and laboratory examination.
Final analysis was performed on 171 patients (group A: 87, group B: 84). The proportion of bowel preparation success (BBPS ≥ 2 for each colonic segment) in group A was not inferior compared to group B (95.4% vs 96.4%, P = 0.736, 1-sided 97.5% lower confidence limit -7.0%). The adenoma detection rate was not different (59.6% vs 41.9%; P = 0.087). The bubble scale was better in group A (0.2 ± 0.9 vs 1.9 ± 1.7, P < 0.001). All adverse events were mild in both groups. Nausea was less frequent in group A (14.9% vs 38.1%, P = 0.001). Overall satisfaction was better in group A (8.1 ± 2.1 vs 6.4 ± 2.8, P < 0.001). No clinically significant laboratory abnormality developed in both groups. These findings were similarly shown in old patients ≥65 years.
Both OST and 1-L PEG-A were efficacious, safe, and tolerable for bowel preparation of colonoscopy. The OST showed fewer bubbles and slightly better tolerability.
This study aimed to investigate the effect of stenting-related factors, including endoscopists' expertise, on clinical outcomes after bridge-to-surgery (BTS) stenting for obstructive colorectal ...cancer (CRC).
We analyzed BTS stenting-related factors, including stenting expertise and the interval between stenting and surgery, in 233 patients (63 13 years, 137 male) who underwent BTS stenting for obstructive CRC. We evaluated the influence of these factors on post-BTS stenting clinical outcomes such as stent-related complications and cancer recurrence.
The interval between stenting and surgery was ≤ 7 days in 79 patients (33.9%) and > 7 days in 154 patients (66.1%). BTS stenting was performed by endoscopists with ≤ 50, 51-100, and > 100 prior stenting experiences in 94, 43, and, 96 patients, respectively. The clinical success rate of BTS stenting was 93.1%. Stent-related and postoperative complications developed in 19 (8.2%) and 20 (8.6%) patients, respectively. Cancer recurrence occurred in 76 patients (32.6%). Short BTS interval of ≤ 7 days increased the risk of postoperative complications (odds ratio OR, 2.61 1.03-6.75; P = 0.043). Endoscopists' stenting experience > 100 showed greater clinical success of stenting (OR, 5.50 1.45-28.39; P = 0.021) and fewer stent-related complications (OR, 0.26 0.07-0.80; P = 0.028) compared with stenting experience ≤ 50. BTS stenting-related factors did not affect long-term oncological outcomes.
Greater expertise of endoscopists was associated with better short-term outcomes, including high stenting success rate and low rate of stent-related complications after BTS stenting for obstructive CRC. An interval of > 7 days between BTS stenting and surgery was required to decrease postoperative complications.
A rapid and accurate molecular fluorescence imaging technique will greatly reduce cancer mortality by overcoming the detection limit of the naked eye in colonoscopy. Two imaging probes are reported ...that can be co‐used for colonoscopic diagnosis: a fluorescent molecular probe, cresyl violet–glutamic acid derivative, that ratiometrically switches between two fluorescent colors in response to the enzyme activity of λ‐glutamyltranspeptidase and an antibody quantum dot probe that is a conjugate of biocompatible AgInS2 quantum dot with matrix metalloproteinase 14 antibodies. Validity of the probes is confirmed using human colon cancer cell lines, ex vivo mouse model tissues, and patient tumor colon tissues in which the tumor lesions are well‐visualized in less than five minutes. Co‐application of the two probes onto fresh colon tissues affords accurate visualization of carcinomas and also hyperplasia and adenoma regions. Fresh human colon adenoma tissues are also valuated, where the two probes show complementary diagnoses of cancer. Two‐photon microscopy shows the time‐dependent depth profiles of the two probes. Both rapidly permeate and populate most at 10–20 µm from the surface. Extensive toxicity studies are performed for the two probes at cellular level and also at the organ level using a small animal model.
A ratiometric fluorescent probe that responds to λ‐glutamyltranspeptidase activity is developed and co‐used with an antibody–quantum dot conjugate probe, which demonstrates the potential for endoscopic early colon cancer diagnosis by multiplexed and complementary detection of colorectal tumors and precancerous regions such as adenoma and hyperplasia.
Objectives
High‐contrast and high‐resolution imaging techniques would enable real‐time sensitive detection of the gastrointestinal lesions. This study aimed to investigate the feasibility of novel ...dual fluorescence imaging using moxifloxacin and proflavine in the detection of neoplastic lesions of the human gastrointestinal tract.
Methods
Patients with the colonic and gastric neoplastic lesions were prospectively enrolled. The lesions were biopsied with forceps or endoscopically resected. Dual fluorescence imaging was performed by using custom axially swept wide‐field fluorescence microscopy after topical moxifloxacin and proflavine instillation. Imaging results were compared with both confocal imaging with cell labeling and conventional histological examination.
Results
Ten colonic samples (one normal mucosa, nine adenomas) from eight patients and six gastric samples (one normal mucosa, five adenomas) from four patients were evaluated. Dual fluorescence imaging visualized detail cellular structures. Regular glandular structures with polarized cell arrangement were observed in normal mucosa. Goblet cells were preserved in normal colonic mucosa. Irregular glandular structures with scanty cytoplasm and dispersed elongated nuclei were observed in adenomas. Goblet cells were scarce or lost in the colonic lesions. Similarity analysis between moxifloxacin and proflavine imaging showed relatively high correlation values in adenoma compared with those in normal mucosa. Dual fluorescence imaging showed good detection accuracies of 82.3% and 86.0% in the colonic and the gastric lesions, respectively.
Conclusions
High‐contrast and high‐resolution dual fluorescence imaging was feasible for obtaining detail histopathological information in the gastrointestinal neoplastic lesions. Further studies are needed to develop dual fluorescence imaging as an in vivo real‐time visual diagnostic method.
Background and Aim
Evidence has emerged that a pretreatment immune profile in rectal cancer is associated with response to chemoradiotherapy (CRT) and recurrence after CRT. However, few studies have ...evaluated the immune profile differences after CRT regarding recurrence and nonrecurrence.
Methods
We included patients with advanced rectal cancer treated with CRT and surgery with recurrence within 1 year in a recurrence group. After sex and age matching with the recurrence group, patients with no recurrence for 3 years after CRT were included in a nonrecurrence group. We extracted the immune profile, including CD3 and CD8, from the surgical specimen after CRT using multispectral fluorescence immunohistochemistry and compared the two groups.
Results
The immune profiles of 65 patients with rectal cancer were assessed; 30 were included in the recurrence group and 35 were included in the nonrecurrence group. CD3+ and CD8+ T lymphocyte densities were significantly higher in the nonrecurrence group than in the recurrence group (CD3+; P < 0.001, CD8+; P = 0.003) in the primary tumor. Consistent results were found in epithelial and stromal cells. Compared with the recurrence group, the distinct profiles of co‐expressed immune markers in the nonrecurrence group were revealed (CD3+CD8+, P = 0.001; CD3+CD8+PD‐L1−, P = 0.001; CD3+CD8+ FOXP3− PD‐L1−, P = 0.001).
Conclusions
Vigorous CD3+ and CD8+ T cell priming post‐CRT was prominent in the nonrecurrence group compared with that of the recurrence group. This finding suggests that differences in immune profiles may have clinical significance even after CRT.
Background and Aim
Data comparing the outcomes of cyclosporin A (CsA) and infliximab (IFX) as rescue therapy for steroid‐refractory acute severe ulcerative colitis (SR‐ASUC) among Asians are scarce.
...Methods
In this single‐center study, we retrospectively reviewed 121 patients with SR‐ASUC according to the Truelove and Witts' criteria who received CsA or IFX as rescue therapy between 1995 and 2015. The cumulative rates of treatment failure and colectomy at 3 months were compared. Treatment failure was defined as colectomy, switch to other medications, acute flare‐up events requiring steroid treatment, or adverse events leading to drug interruption.
Results
Among 121 patients with SR‐ASUC (male, 55.6%; median disease duration, 47.1 months; extensive colitis, 61.2%), 23 received CsA as rescue therapy. Baseline characteristics (e.g. age at diagnosis, sex, disease duration, disease extent at rescue therapy, and Mayo score at treatment initiation) were comparable between the two groups. During follow‐up (median, 45 months; interquartile range 29.3–61.8), 84 patients (69.4%) experienced treatment failure, and 25 patients (20.7%) underwent colectomy. The CsA group and the IFX group did not show significant differences in the cumulative rates of treatment failure (39.1% vs 34.7%, P = 0.714) and colectomy (26.1% vs 13.3%, P = 0.198) at 3 months. Previous use of azathioprine (odds ratio OR = 2.309, 95% confidence interval CI = 1.076–4.951, P = 0.032) was associated with treatment failure at 3 months. Mayo score > 10 at the time of rescue therapy was significantly associated with colectomy at 3 months (OR = 8.444, 95% CI = 2.592–27.506, P < 0.001).
Conclusion
Among Korean patients with SR‐ASUC, the rates of treatment failure and colectomy at 3 months were not significantly different between the CSA and the IFX treatment groups.
Background and Aim
The feasibility of endoscopic submucosal dissection (ESD) as a treatment option for dysplasia in ulcerative colitis (UC) has been reported, but the associated therapeutic ...decision‐making and clinical outcomes have not been extensively investigated.
Methods
We retrospectively reviewed 25 UC patients who were referred for potential ESD of non‐polypoid or sessile dysplasia. We analyzed the treatment decisions and the ESD and colectomy outcomes for this patient group.
Results
All lesions were located at the colitic segments. The median UC duration was 13.4 years. A colectomy was recommended for 10 patients because of ulceration with indistinct borders (one patient), non‐ulceration with indistinct borders (two patients), and non‐lifting signs (seven patients). The remaining 15 patients underwent ESD. The en bloc and R0 resection rates were 93.3% and 80%, respectively. The median hospitalization periods were 1 (range, 1–2) day after ESD and 7 (range, 5–30) days after colectomy. No procedure‐related complications occurred after ESD, but early and late postoperative complications occurred in two (22.2%) and six (66.7%) of the colectomized patients, respectively. Fourteen ESD cases were followed endoscopically for a median period of 24.7 (range, 5.2–64.8) months. Local recurrence occurred in 2 (14.3%) patients, and metachronous recurrence was identified in two separate patients (14.3%).
Conclusions
Endoscopic submucosal dissection is a feasible endoscopic treatment option for UC‐associated dysplasia showing noninvasive pit or vascular patterns, no surface ulceration, distinct borders, and appropriate lifting after submucosal injection. Meticulous endoscopic surveillance is essential to monitor for local or metachronous recurrence of dysplasia after ESD.
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