Diagnostic Accuracy of JES Classification for Prediction of Invasion Depth in Superficial Esophageal Squamous Carcinoma: Meta-Analysis.

Prediction of the depth of invasion in superficial oesophageal squamous carcinoma (SESC) is an important factor for choosing the treatment. Recently, the Japan Esophageal Society (JES) designed a magnifying endoscopy classification based on the Inoue and Arima classifications. The aim of this study was to conduct a meta-analysis of the published literature on JES classification. Meta-Disc version 1.4, Review Manager 5.4 as well as stata 14.0 were used. The analysis combined sensitivity and specificity with the respective 95% CI, to draw a summary receiver operating characteristic curve (SROC), and estimated the area under curve (AUC) for overdiagnosis and underdiagnosis for each type B. Eight studies were included in the meta-analysis comprising 1279 patients. Type B1 has high sensitivity (0.86, 95%CI: 0.83-0.88) and specificity (0.84, 95%CI: 0.81-0.88) for the prediction of EP/LPM classifications. The AUC was calculated to be 0.92 with a high proportion of underdiagnosis (17%). The sensitivity and specificity of type B2 were 0.66 (95% CI, 0.6-0.72) and 0.84 (95% CI, 0.82-0.86) respectively. The overdiagnosis and underdiagnosis of type B2 were 14% and 39%. Type B3, sensitivity was low (0.49, 95% CI: 0.41-0.56), with high specificity and AUC (specificity: 0.99; AUC: 0.95). JES classification is a useful and reliable modality for predicting the depth of invasion of SESC, but other modalities should be considered for additional assessment when type B2 is detected. Key Words: JES classification, Superficial oesophageal squamous carcinoma, Depth of invasion, Magnifying endoscopy, Meta-analysis.

Species and structural diversity of trees at the structural type level.

BACKGROUND: Species and structural diversity are important for understanding the formation of forest communities, key ecological processes, and improving forest ecological functions and services, but their spatial characteristics have received little attention. Based on the spatial relationships among neighbouring trees, we proposed to divide trees within a structural unit into 15 structural types, and used the univariate distributions of the uniform angle index (W), mingling (M), and dominance (U), along with four common species diversity indices, to analyse the diversity of structural types in natural forests near the Tropic of Cancer. RESULTS: Only a portion of clumped class maintained aggregation, most exhibited a random pattern. Species mixture increased exponentially across distribution classes, and abundance and richness exhibited an initial increase followed by a slight decrease. The distribution patterns of mixture classes varied from highly clustered to random, and M distributions gradually shifted from an inverted J-shaped curve to a J-shaped curve. Abundance and richness exhibited an exponential distribution, whereas the Shannon-Wiener index increased linearly. The W distribution of differentiation classes approximated a normal distribution, whereas M distributions exhibited a J shape. The U distribution of each structure type was approximately 0.2. CONCLUSIONS: These results reveal the species and structural diversity characteristics of trees at the structural type level and expand our knowledge of forest biodiversity. The new method proposed here should significantly contribute to biodiversity monitoring efforts in terrestrial ecosystems, and suggests that higher standards for the simulation and reconstruction of stand structure, as well as thinning in near-natural forests, is warranted.

Effect of Reinforced Video by WeChat on Adenoma Detection Rate for Colonoscopy.

OBJECTIVE: To evaluate the influence of reinforced educational video through smartphone WeChat on adenoma detection rate (ADR). STUDY DESIGN: Randomised controlled study. Place and Duration of the Study: Department of Gastroenterology, Xiantao First People's Hospital affiliated to Yangtze University, Hubei, China, from May 2020 to December 2021. METHODOLOGY: All participants received written instructions regarding bowel preparation and diet before colonoscopy. After randomisation, patients in video group received educational videos through WeChat, two days before the colonoscopy. The primary endpoint was ADR. The secondary outcomes were polyp detection rate (PDR), quality of bowel preparation, adverse events, and satisfaction with preparation. RESULTS: Five-hundred and sixty-four patients were included in the study (284 in video group and 280 in non-video group). ADR was similar in both groups without significant difference (26.4% vs. 23.2%, p=0.38). PDR was not different among the two groups (31.7% vs. 30.4%). The total cleansing score and percentage of adequate bowel preparation in the video group were higher compared with non-video group (p<0.05). Moreover, patient satisfaction was also higher in video group (p=0.048), and the incidence of adverse events in both groups was similar. CONCLUSION: The availability of a supplementary educational video before colonoscopy was insufficient to improve ADR and PDR, but offered benefits on bowel preparation quality and patient satisfaction. KEY WORDS: Video, Adenoma detection rate, Bowel preparation, Colonoscopy.

Exposed Rock Reduces Tree Size, but Not Diversity.

Karst made up of limestone is widely considered a "Noah's ark" of biodiversity. Rock and soil substrates comprise two different site types in karst terrain, although both can support dense forests. However, it is unclear whether and how the presence of exposed rock affects forest diversity and tree size. We established a 2.2 ha plot (200 × 110 m) in an old-growth oak forest (> 300 years) in karst terrain in southwestern China. We classified the plot into rock and soil components; we analyzed plant diversity and tree size in each component using species diversity indices (richness, number of individuals, Shannon-Wiener index, and Pielou evenness index), stand spatial structure parameters, diameter at breast height (DBH), tree height (TH), and tree basal area (BA). We also analyzed the distributional patterns of species at the sites using non-metric multidimensional scaling, then assessed the effects of abiotic environmental variables on diversity and tree size using redundancy analysis. Our results indicated that both site types (i.e., rock and soil) had similar overall species diversity; trees and shrubs were largely distributed at random within the study site. Tree size was evenly differentiated in the community, and trees were dominant, particularly on soil. Trees on rock were in a status of medium mixture, whereas shrubs on rock were highly mixed. The opposite trend was observed for trees and shrubs growing on soil. The DBH, TH, and BA were smaller in trees growing on rock than in trees growing on soil. Abiotic environmental variables had varying effects on the diversity and size of trees at the two site types; they only explained 21.76 and 14.30% of total variation, respectively. These results suggest that exposed rock has the effect of reducing tree size, but not diversity, thus highlighting the important role of rock in maintaining diversity; moreover, the results imply that karst microhabitats may mitigate the impacts of topography on tree diversity and growth. Greater attention should be focused on exposed rock in the conservation and management of karst forests and the restoration of degraded forest ecosystems.

The Abundance and Structure of Deadwood: A Comparison of Mixed and Thinned Chinese Fir Plantations.

The sustainability of coniferous monoculture plantations is facing challenges with respect to yields, ecology, and biodiversity. Conversion of monocultural coniferous plantations into mixed stands using thinning or direct mixed planting is widely considered to be a key strategy for overcoming these challenges and transforming the characteristics of plantations on a regional scale. Substantial amounts of deadwood may be produced in mixed forests (MFs); this material is important for evaluating and modifying forest management methods, understanding the dynamics of forest stands, and achieving biodiversity conservation. We assessed the quantitative characters and diameter distributions of deadwood in mixed and thinned Chinese fir [Cunninghamia lanceolata (Lamb.) Hook.] forests over one rotation. We used the g(r) function and spatial parameters to analyze the spatial structure of deadwood, and used logistic regression and Hegyi's competition index (HCI) to explore competition and mortality. Our results indicate that: (1) Chinese fir dominated in all groups of deadwood (snags, broken wood, and fallen wood), and the abundance, volume, and mortality rates of deadwood were much lower in the thinning forest compared to the MF. (2) Later coming populations (LCPs) comprised the majority of the small diameter classes in the thinning forest, but only accounted for a small proportion of the MF. (3) Broken wood in the thinning forest was randomly distributed, while the other types of deadwood were clustered at most spatial scales. In contrast, the spatial patterns in the MF were random at most spatial scales. (4) Total deadwood in both stands was in a status of intermediate and was randomly surrounded by its four nearest neighbors. All types of deadwood were highly mixed in the thinning forest and moderately mixed in the MF. Our case study suggests that thinning and mixing result in different stand development processes and thus influence the type, amount, and structure of deadwood. Thinning significantly reduces competition, which is the main driver of tree mortality. Converting pure Chinese fir plantations into mixed stands by thinning should be taken in future. Understanding tree mortality after conversion is essential to select appropriate silvicultural treatments and achieve ultimately sustainable forest management.

The effect of using simethicone with or without N-acetylcysteine before gastroscopy: A meta-analysis and systemic review.

BACKGROUND/AIM: To assess the efficacy and safety of simethicone with or without N-acetylcysteine (NAC) as premedications before gastroscopy. MATERIALS AND METHODS: We searched EMBASE, PubMed, Cochrane library and Web of Science database for randomized clinical controlled trials regarding simethicone ± NAC as oral drinking agents before gastroscopy. Statistical software RevMan5.3 was used for statistical analysis. RESULTS: Ten randomized clinical trials that fulfilled the inclusion criteria were further pooled into a meta-analysis, which included 5,750 patients. The rate of positive findings in simethicone plus NAC group was higher than that in water group (risk ratio [RR] =1.31, 95%CI: 1.12-1.53, P = 0.0006) with high level of evidence. There was no significant difference on the rate of positive findings when comparing simethicone with simethicone plus NAC (RR = 1.02, 95%CI: 0.90-1.16, P = 0.71) and with water (RR = 1.13, 95%CI: 0.82-1.55, P = 0.46), respectively. Simethicone plus NAC showed better total mucosal visibility score than simethicone alone (MD = -0.14 (-0.25, -0.03), P = 0.01) without obvious heterogeneity. Both simethicone plus NAC and simethicone alone offer more benefit than water. The procedure time in simethicone group was shorter than that in water group (MD = -1.23 (-1.51, -0.96), P < 0.00001). Regarding adverse events, there was no significant difference in simethicone and water group (RR = 0.45, 95%CI: 0.2-1.0, P = 0.05, I2 = 0%). CONCLUSIONS: As premedication of gastroscopy, simethicone plus NAC offers more benefit on positive findings and total mucosal visibility score.

Above- and below-ground carbon stocks in an indigenous tree (Mytilaria laosensis) plantation chronosequence in subtropical China.

More than 60% of the total area of tree plantations in China is in subtropical, and over 70% of subtropical plantations consist of pure stands of coniferous species. Because of the poor ecosystem services provided by pure coniferous plantations and the ecological instability of these stands, a movement is under way to promote indigenous broadleaf plantation cultivation as a promising alternative. However, little is known about the carbon (C) stocks in indigenous broadleaf plantations and their dependence on stand age. Thus, we studied above- and below-ground biomass and C stocks in a chronosequence of Mytilaria laosensis plantations in subtropical China; stands were 7, 10, 18, 23, 29 and 33 years old. Our assessments included tree, shrub, herb and litter layers. We used plot-level inventories and destructive tree sampling to determine vegetation C stocks. We also measured soil C stocks by analyses of soil profiles to 100 cm depth. C stocks in the tree layer dominated the above-ground ecosystem C pool across the chronosequence. C stocks increased with age from 7 to 29 years and plateaued thereafter due to a reduction in tree growth rates. Minor C stocks were found in the shrub and herb layers of all six plantations and their temporal fluctuations were relatively small. C stocks in the litter and soil layers increased with stand age. Total above-ground ecosystem C also increased with stand age. Most increases in C stocks in below-ground and total ecosystems were attributable to increases in soil C content and tree biomass. Therefore, considerations of C sequestration potential in indigenous broadleaf plantations must take stand age into account.

[Stand density estimation based on the measurement of spatial structure].

This study estimated stem density by combining distance sampling with stand spatial structure investigation techniques. We tested the statistical performance of two investigative methods (selecting the fourth- or sixth-nearest tree to the sample location) and three different density estimators (Prodan, Persson and Thompson). Different spatial distribution patterns influenced the performance of these estimators. Prodan's estimator was unbiased for uniform patterns, and it produced increasing bias with increasing spatial clustering. Persson's estimator produced consistent positive bias for uniform and random patterns, with the smallest bias for clustered patterns. Thompson's estimator was robust for random or near-random patterns, and it produced positive and negative bias for uniform and clustered patterns, respectively. No significant performance difference was found between selecting the fourth- and the sixth-nearest trees with the same sample size of 49. Thus, we could combine distance sampling with spatial structure investigation techniques.