Raman spectroscopy with an improved support vector machine for discrimination of thyroid and parathyroid tissues.

The objective of this study was to discriminate thyroid and parathyroid tissues using Raman spectroscopy combined with an improved support vector machine (SVM) algorithm. In thyroid surgery, there is a risk of inadvertently removing the parathyroid glands. At present, there is a lack of research on using Raman spectroscopy to discriminate parathyroid and thyroid tissues. In this article, samples were obtained from 43 individuals with thyroid and parathyroid tissues for Raman spectroscopy analysis. This study employed partial least squares (PLS) to reduce dimensions of data, and three optimization algorithms are used to improve the classification accuracy of SVM algorithm model in spectral analysis. The results show that PLS-GA-SVM algorithm has higher diagnostic accuracy and better reliability. The sensitivity of this algorithm is 94.67% and the accuracy is 94.44%. It can be concluded that Raman spectroscopy combined with the PLS-GA-SVM diagnostic algorithm has significant potential for discriminating thyroid and parathyroid tissues.

Environmental Effects on Taxonomic Turnover in Soil Fauna across Multiple Forest Ecosystems in East Asia.

The large-scale spatial variation in and causes of biotic turnover of soil fauna remain poorly understood. Analyses were conducted based on published data from 14 independent sampling sites across five forest ecosystems in East Asia. Jaccard and Sørensen's indices were used to measure turnover rates in soil fauna orders. A redundancy analysis was used to investigate multiple environmental controls of the composition of soil fauna communities. The results showed that both Jaccard's and Sørensen's index increased significantly with increasing latitude difference. The environment explained 54.1%, 50.6%, 57.3% and 50.9% of the total variance, and spatial factors explained 13.8%, 15.9%, 21.0% and 12.6% of the total variance in the orders' composition regarding overall, phytophagous, predatory and saprophagous fauna, respectively. In addition, climate factors in environmental processes were observed to have a stronger effect than soil factors on the orders' turnover rates. Our results support the hypothesis that the effect of environment factors on soil animal taxa turnover is more important than the effect of spatial factors. Climatic factors explained more variation in the turnover of phytophagic fauna, but soil and environment factors equally explained the variation in the turnover of predatory fauna. This study provides evidence to support both environmental filtering and dispersal limitation hypotheses at the regional and population scales.

Impact of dexmedetomidine on secondary hyperparathyroidism recurrence in uremic patients who received parathyroidectomy with auto-transplantation: a retrospective propensity-matched study.

BACKGROUND: Recurrence of secondary hyperparathyroidism (SHPT) remains a big challenge in uremic patients who underwent total parathyroidectomy with auto-transplantation (tPTX-AT). However, the relationship between perioperative intervention and recurrence of SHPT remains unclear. Dexmedetomidine has been used safely and effectively in uremic patients' anesthesia. The aim of the study was to explore the effect of dexmedetomidine on the recurrence of SHPT and identify the possible mechanism of action. METHODS: Records of patients who underwent tPTX-AT between 2017 and 2018 were retrospectively analyzed. The study consisted of patients who received dexmedetomidine intra-operatively and the control patients who did not receive dexmedetomidine. The primary endpoint was the difference in the recurrence of SHPT one year after the surgery between the two groups. The secondary endpoint was health-related quality of life scores. Analysis included propensity score matching and multivariable logistic regression. RESULTS: Of 354 patients, 133 patients received dexmedetomidine intra-operatively, and the total recurrence rate of SHPT was 10.2%. After propensity score matching, we found that patients' age, dexmedetomidine infusion, comorbidity of diabetes, and preoperative serum phosphorus were independent factors for SHPT recurrence, and that patients who received dexmedetomidine had an estimated 3.80-fold decrease in the risk of SHPT recurrence (odds ratio, 0.263; 95% confidence interval, 0.081 to 0.854; P=0.026). Patients receiving intraoperative dexmedetomidine infusion exhibited a better quality of life in terms of physical functioning and general health, and less emotional role limitations compared with those in the control group. CONCLUSION: In uremic patients who received tPTX-AT, there was an association between dexmedetomidine use and decreased risk of SHPT recurrence one year after the surgery. Further studies are needed to accurately assess the effects and mechanism of action of dexmedetomidine on the prognosis of this population.

Changes in the Distribution Preference of Soil Microbial Communities During Secondary Succession in a Temperate Mountain Forest.

Soil microbes play a crucial role in a forest ecosystem. However, whether the distribution of bacteria and fungi in different forest succession stages is random or following ecological specialization remains to be further studied. In the present study, we characterized soil bacterial and fungal communities to determine their distribution preference, with different succession communities in a temperate mountain forest. The Kruskal-Wallis method was used to analyze structural differences between bacterial and fungal communities in different succession processes. The specificity of soil microbial distribution in a secondary forest was studied by network analysis. The torus-translation test was used to analyze the species distribution preference of soil microbes in different succession stages. Results showed that the species composition of soil bacteria and fungi differed significantly in different succession processes. The modularity index of fungi (0.227) was higher than that of bacteria (0.080). Fungi (54.47%) had specific preferences than bacteria (49.95%) with regard to forests in different succession stages. Our work suggests that the distribution pattern of most soil microbes in a temperate mountain forest was not random but specialized in temperate mountain forests. Different microbes showed different distribution preferences. Fungi were more sensitive than bacteria during secondary succession in a temperate mountain forest. In addition, microbe-environment relations varied during secondary succession. Our results provided new insight into the mechanism through which complex soil microbial communities responded to changes in forest community succession.

Risk assessment of COVID-19 infection for subway commuters integrating dynamic changes in passenger numbers.

The COVID-19 global pandemic has had a significant impact on mass travel. We examined the risk of transmission of COVID-19 infection between subway commuters using the Susceptible Exposed Infected Recovered (SEIR) model. The model considered factors that may influence virus transmission, namely subway disinfection, ventilation capacity, average commuter spacing, single subway journey time, COVID-19 transmission capacity, and dynamic changes in passenger numbers. Based on these parameters, above a certain threshold (25 min), the risk of infection for susceptible people increased significantly as journey time increased. Average distance between commuters and levels of ventilation and disinfection were also important influencing factors. Meanwhile, the model also indicated that the risk of infection varied at different times of the day. Therefore, this paper recommends strengthening ventilation and disinfection in the carriages and limiting the time of single journeys, with an average distance of at least 1 m between passengers. In this light, subway commuters need to take proactive precautions to reduce their risk of COVID-19 infection. Also, the results show the importance of managing subway stations efficiently during epidemic and post-epidemic eras.

Glutamate Oxidase-Integrated Biomimetic Metal-Organic Framework Hybrids as Cascade Nanozymes for Ultrasensitive Glutamate Detection.

The hybrid coupling of biocatalysts and chemical catalysts plays a vital role in the fields of catalysis, sensing, and medical treatment due to the integrated advantages in the high activity of natural enzymes and the excellent stability of nanozymes. Herein, a new nanozyme/natural enzyme hybrid biosensor was established for ultrasensitive glutamate detection. The MIL-88B(Fe)-NH2 material with remarkable peroxidase mimic activity and stability was used as a nanozyme and carrier for immobilizing glutamate oxidase (GLOX) through Schiff base reaction to construct a chem-enzyme cascade detector (MIL-88B(Fe)-NH2@GLOX). The resultant MIL-88B(Fe)-NH2@GLOX exhibited a wide linear range (1-100 µM), with a low detection limit of 2.5 µM for glutamate detection. Furthermore, the MIL-88B(Fe)-NH2@GLOX displayed excellent reusability and storage stability. After repeated seven cycles, MIL-88B(Fe)-NH2-GLOX (GLOX was adsorbed on MIL-88B(Fe)-NH2) lost most of its activity, whereas MIL-88B(Fe)-NH2@GLOX still retained 69% of its initial activity. Meanwhile, MIL-88B(Fe)-NH2@GLOX maintained 60% of its initial activity after storage for 90 days, while free GLOX only retained 30% of its initial activity. This strategy of integrating MOF mimics and natural enzymes for cascade catalysis makes it possible to design an efficient and stable chemo-enzyme composite catalysts, which are promising for applications in biosensing and biomimetic catalysis.

Identification of susceptibility gene mutations associated with the pathogenesis of familial nonmedullary thyroid cancer.

BACKGROUND: Familial nonmedullary thyroid cancer (FNMTC) accounts for approximately 3%-9% of all thyroid cancers; however, the mechanisms underlying FNMTC remain unclear. Environmental and genetic (especially genetic mutation) factors may play important roles in FNMTC etiology, development, and pathogenesis. METHODS: Three affected members, including two first-degree relatives, and three healthy members of a family with FNMTC were studied. We performed whole-exome and targeted gene sequencing to identify gene mutations that may be associated with FNMTC pathogenesis. The results were analyzed using Exome Aggregation Consortium data and the Genome Aggregation Database and further validated using Sanger sequencing. RESULTS: Of 28 pivotal genes with rare nonsynonymous mutations found, 7 were identified as novel candidate FNMTC pathogenic genes (ANO7, CAV2, KANK1, PIK3CB, PKD1L1, PTPRF, and RHBDD2). Among them, three genes (PIK3CB, CAV2, and KANK1) are reportedly involved in tumorigenesis through the PI3K/Akt signaling pathway. CONCLUSION: We identified seven pathogenic genes in affected members of a family with FNMTC. The PI3K/Akt signaling pathway is thought to be closely related to the development of FNMTC, and three of the susceptibility genes identified herein are associated with this pathway. These findings expand our understanding of FNMTC pathogenesis and underscore PI3K/Akt pathology as a potential therapy target.

Stand Structure and Substrate Diversity as Two Major Drivers for Bryophyte Distribution in a Temperate Montane Ecosystem.

Elucidating the major drivers of bryophyte distribution is the first step to protecting bryophyte diversity. Topography, forest, substrates (ground, tree trunks, roots, rocks, and rotten wood), and spatial factor, which factors are the major drivers of bryophyte distribution? In this study, 53 plots were set in 400 m2 along the elevation gradient in Xiaoqinling, China. All bryophytes in the plots were collected and identified. Regression analysis was used to examine the relationship between bryophyte and substrate diversity. We compared the patterns of overall bryophyte diversity and diversity of bryophytes found on the ground, tree, and rock along elevational gradients. Canonical correspondence analysis was applied to relate species composition to selected environmental variables. The importance of topography, forest, substrates, and spatial factors was determined by variance partitioning. A total of 1378 bryophyte specimens were collected, and 240 species were identified. Bryophyte diversity was closely related to substrate diversity. The overall bryophyte diversity significantly increased with elevation; however, the response varied among ground, tree, and rock bryophytes. Tree diversity and herb layer were considered important environmental factors in determining bryophyte distribution. Species abundance was best explained by stand structure (17%), and species diversity was best explained by stand structure (35%) and substrate (40%). Results directly indicated that substrate diversity can improve bryophyte species diversity. The effects of micro-habitat formed by stand structure and substrate diversity were higher than those of spatial processes and topography factors on bryophyte distribution. This study proved that the determinant factors influencing bryophyte diversity reflect the trends in recent forest management, providing a real opportunity to improve forest biodiversity conservation.

Knockdown of FOXK1 inhibited the proliferation, migration and invasion in hepatocellular carcinoma cells.

FOXK1 (forkhead box k1), a member of the FOX family, is overexpressed in several types of solid tumors. However, the biological function of FOXK1 in hepatocellular carcinoma (HCC) remains poorly understood. In the present study, we investigated the expression status and functional roles of FOXK1 in HCC. Our results demonstrated that the expression of FOXK1 was significantly up-regulated in human HCC tissues and cell lines. In addition, down-regulation of FOXK1 suppressed the proliferation, migration and invasion of HCC cells in vitro, as well as attenuated tumor growth in nude mice model. We further elucidated that knockdown of FOXK1 down-regulated the protein expression levels of ß-catenin, c-myc and cyclin D1 in HepG2 cells. In conclusion, the present study indicated that FOXK1 may act as an oncogene in human HCC, and knockdown of FOXK1 significantly inhibited HCC cell proliferation, migration and invasion, partly through the inactivation of Wnt/ß-catenin signaling pathway. These findings suggest that FOXK1 may be a novel therapeutic target to treat HCC.

Effects of Environment and Space on Species Turnover of Woody Plants across Multiple Forest Dynamic Plots in East Asia.

Species turnover is fundamental for understanding the mechanisms that influence large-scale species richness patterns. However, few studies have described and interpreted large-scale spatial variation in plant species turnover, and the causes of this variation remain elusive. In addition, the determinants of species turnover depend on the dispersal ability of growth forms. In this study, we explored the large-scale patterns of woody species turnover across the latitude gradient based on eight large stem-mapping plots (covering 184 ha forest) in East Asia. The patterns of woody species turnover increased significantly with increasing latitude differences in East Asia. For overall woody species, environment explained 36.30, 37.20, and 48.48% of the total variance in Jaccard's (ßj), Sorenson's, (ßs), and Simpson's dissimilarity (ßsim). Spatial factors explained 47.92, 48.39, and 41.38% of the total variance in ßj, ßs, and ßsim, respectively. The effects of pure spatial and spatially structured environments were stronger than pure environmental effects for overall woody species. Our results support the hypothesis that the effect of neutral processes on woody species turnover is more important than the effect of the environment. Neutral processes explained more variation for turnover of tree species, and environmental factors explained more variation for the turnover of shrub species on a large scale. Therefore, trees and shrubs should be subjected to different protection strategies in future biodiversity conservation efforts.