Temporal and Spatial Variation of Aboveground Biomass of Pinus densata and Its Drivers in Shangri-La, CHINA

Understanding the drivers of forest aboveground biomass (AGB) is essential to further understanding the forest carbon cycle. In the upper Yangtze River region, where ecosystems are incredibly fragile, the driving factors that make AGB changes differ from other regions. This study aims to investigate AGB's spatial and temporal variation of Pinus densata in Shangri-La and decompose the direct and indirect effects of spatial attribute, climate, stand structure, and agricultural activity on AGB in Shangri-La to evaluate the degree of influence of each factor on AGB change. The continuous sample plots from National Forest Inventory (NFI) and Landsat time series were used to estimate the AGB in 1987, 1992, 1997, 2002, 2007, 2012, and 2017. The structural equation model (SEM) was used to analyze the different effects of the four factors on AGB based on five scales: entire, 1987-2002, 2007-2017, low population density, and high population density. The results are as follows: (1) The AGB of Pinus densata in Shangri-La decreased from 1987 to 2017, with the total amount falling from 9.52 million tons to 7.41 million tons, and the average AGB falling from 55.49 t/ha to 40.10 t/ha. (2) At different scales, stand structure and climate were the drivers that directly affect the AGB change. In contrast, the agricultural activity had a negative direct effect on the AGB change, and spatial attribute had a relatively small indirect effect on the AGB change. (3) Analyzing the SEM results at different scales, the change of the contribution of the agricultural activity indicates that human activity is the main negative driver of AGB change in Shangri-La, especially at the high population density region. In contrast, the change of the contribution of the stand structure and climate indicates that the loss of old trees has an important influence on the AGB change. Forest resources here and other ecologically fragile areas should be gradually restored by adhering to policies, such as strengthening forest protection, improving forest stand quality, and limiting agricultural production activities.

Effect of RFRP-3, the mammalian ortholog of GnIH, on apoptosis and autophagy in porcine ovarian granulosa cells via the p38MAPK pathway

RFamide-related peptide-3 (RFRP-3) has been proposed as a key inhibitory regulator of mammalian reproduction. Our previous studies demonstrated that RFRP-3 mediated apoptosis and autophagy of the epididymis in rats and inhibited porcine granulosa cell (GC) proliferation. However, the molecular mechanisms of the RFRP-3 effect on porcine GC apoptosis and autophagy have not been studied before. Herein, we first investigated the role of RFRP-3 in apoptosis and autophagy in cultured porcine GCs in vitro. Our results showed that different doses of RFRP-3 dose-dependently elevated the expression of autophagy markers at both the mRNA and protein levels, whereas the expression of apoptosis markers exhibited a bidirectional, dose-dependent effect. Because the p38MAPK signaling pathway plays essential roles in apoptosis and autophagy, we subsequently evaluated the effect of RFRP-3 on p38MAPK activation. The results showed that 10^-6 M RFRP-3 treatment not only significantly decreased p38MAPK phosphorylation but also inhibited the p38MAPK activator U-46619 to promote p38MAPK activation in porcine GCs. Finally, we applied U-46619 to investigate the role of the p38MAPK signaling pathway in apoptosis and autophagy in RFRP-3-treated porcine GCs. The results showed that all doses of RFRP-3 significantly inhibited the U-46619-induced increase in apoptosis in a dose-dependent manner. However, except for the U-46619-induced Beclin-1 expression increase, which was significantly suppressed in high-dose RFRP-3-treated porcine GCs, other doses of RFRP-3 treatment strengthened the U-46619-induced increase in other autophagy markers. In summary, our data demonstrate a critical role for the p38MAPK signaling pathway in the porcine GC cellular response to RFRP-3 by controlling the balance between apoptosis and autophagy.

Clinical outcomes of keratinized mucosa augmentation in jaws reconstructed with fibula or iliac bone flaps

This prospective study was undertaken to evaluate the treatment outcomes of keratinized mucosa augmentation (KMA) on the buccal and palatal/lingual sides of implants in jaws reconstructed after oncological surgery. Forty-two implants in 12 patients whose jaws had been reconstructed with a fibula or iliac bone flap were included. KMA was performed at 3 months after implant placement; this included an apically displaced partial-thickness flap and a free gingival graft (FGG) around the implants to increase the keratinized mucosa width (KMW). Patients were followed up for at least 6 months post-surgery. KMW, shrinkage, and patient pain and discomfort measured on a visual analogue scale were analysed. A histological analysis was performed of tissue epithelium from two patients. The results showed that KMW was >2 mm on both the buccal and palatal/lingual sides during follow-up. Before surgery, histological analysis showed epithelium with no epithelial spikes; normal keratinized epithelial spikes were observed at 8 weeks after KMA. Greater KMW was observed around implants in reconstructed maxillae than around those in reconstructed mandibles (P < 0.001). Patients felt more pain at the donor site than at the recipient site during the first 3 days post-surgery. KMA with FGG was predictable in reconstructed jaws and may help maintain the long-term stability of implants.

LINC00174 triggers the malignant development of breast cancer by negatively regulating miR-1827 level

OBJECTIVE

Long non-coding RNAs (lncRNAs) are extensively involved in tumor development. In-depth researches on cancer-associated lncRNAs provide a theoretical basis for developing prognostic hallmarks and individualized therapeutic targets in breast cancer (BCa). This study aims to detect expression characteristics of LINC00174 in BCa and its biological role in regulating BCa cell phenotypes.

PATIENTS AND METHODS

LINC00174 levels in BCa and adjacent normal tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The influence of LINC00174 on pathological indicators of BCa was analyzed. In MCF-7 and MDA-MB-231 cells with LINC00174 knockdown, proliferative and migratory abilities were examined by cell counting kit-8 (CCK-8), colony formation and transwell assay, respectively. At last, molecular mechanisms of LINC00174 and its downstream gene miR-1827 in regulating BCa development were explored by Luciferase assay and rescue experiments.

RESULTS

LINC00174 was upregulated in BCa tissues than adjacent normal ones. High level of LINC00174 predicted advanced tumor staging, high metastasis rate and poor prognosis in BCa. Knockdown of LINC00174 attenuated proliferative and migratory abilities in BCa cells. MiR-1827 was the target gene binding LINC00174, showing a negative correlation between each other. Silence of miR-1827 abolished the regulatory effects of LINC00174 on proliferative and migratory abilities in BCa cells.

CONCLUSIONS

LINC00174 is upregulated in BCa samples. It is closely linked to tumor staging, metastasis and prognosis in BCa. By negatively regulating miR-1827 level, LINC00174 aggravates the malignant development of BCa.

Machine learning from quantitative coronary computed tomography angiography predicts ischemia and impaired myocardial blood flow

Background

Atherosclerotic plaque characteristics influence the hemodynamic consequences of coronary lesions. This study sought to assess the performance of a machine learning (ML) score integrating coronary computed tomography angiography (CCTA)-based quantitative plaque features for the prediction of ischemia by invasive fractional flow reserve (FFR) and impaired myocardial blood flow (MBF) by [15O]H2O positron emission tomography (PET).

Methods

This post-hoc analysis of the PACIFIC (Prospective Comparison of Cardiac PET/CT, SPECT/CT Perfusion Imaging and CT Coronary Angiography With Invasive Coronary Angiography) trial included 208 patients with suspected coronary artery disease who underwent CCTA, [15O]H2O PET, and 3-vessel invasive FFR. Plaque quantification from CCTA was performed using semiautomated software. A boosted ensemble ML algorithm (XGBoost) trained on data from the NXT (Analysis of Coronary Blood Flow using CT Angiography: Next Steps) trial was used to develop a ML score for the prediction of per-vessel ischemia (invasive FFR ≤0.80). The performance of the ML score was evaluated in 551 vessels from the PACIFIC trial for external validation. Thereafter, we assessed the discriminative ability of the ML score for per-vessel impaired hyperemic MBF (≤2.30 mL/min/g).

Results

In total, 138 (25.0%) vessels had ischemia and 195 (35.4%) vessels had impaired hyperemic MBF. CCTA-derived quantitative percent diameter stenosis and low-density noncalcified plaque (LDNCP) volume were higher in ischemic vessels compared with non-ischemic vessels (60.8% vs. 19.9%; and 42.3 mm3 vs. 9.1 mm3; both p&lt;0.001). The ML score demonstrated a significantly higher area under the receiver-operating characteristic curve (AUC) for predicting ischemia (0.92, 95% confidence interval [CI] 0.89–0.94) compared with visual stenosis grade (0.84, 95% CI 0.80–0.87; p&lt;0.001). Overall, quantitative percent diameter stenosis and LDNCP volume had greatest feature importance for ML, followed by percent area stenosis, minimum luminal diameter, and contrast density drop (Figure 1). An individualized explanation of ML ischemia prediction is shown in Figure 2. When applied for impaired MBF discrimination, the ML score exhibited an AUC of 0.82 (95% CI 0.78–0.85) and was superior to visual stenosis grade (AUC 0.76, 95% CI 0.72–0.80; p=0.03).

Conclusions

An externally validated ML score integrating CCTA-based quantitative plaque features accurately predicts FFR-defined ischemia and abnormal MBF by PET, outperforming standard visual CCTA interpretation.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, and Blood Institute, United States Performance of the ML scoreIndividual explanation of ML prediction

[Trajectories of body mass index Z-score and risk of high blood pressure in late adolescence in Suzhou children]

Objective: To identify age and gender standardized body mass index among children and adolescents and explore their associations with high blood pressure (HBP) in late adolescence. Methods: The current study was based on the Health Promotion Program for Children and Adolescents, school-based surveillance successively conducted from 2012 to 2019 in Suzhou, China. A total of 11 812 children and adolescents aged 16-18 years, who had ≥4 examination records during 2012-2018 and were also involved in a surveillance program in 2019, were included. Latent class growth mixture modeling was used to identify the BMI-Z trajectories in different genders, and multivariate logistic regression was used to analyze the associations between different BMI-Z trajectories and risk of HBP in late adolescence. Results: Six distinct BMI-Z trajectories were determined for both genders:thin, slightly thin,standard, declining, overweight, and obese. Compared with the regular group, the obesity group had 94.0% (OR=1.94, 95%CI: 1.43-2.63) and 107.0% (OR=2.07, 95%CI: 1.33-3.22) increased risk of developing HBP in late adolescence in boys and girls, respectively. However, a neutral association was found between the descending group and HBP in late adolescence. Conclusions: Persistent obesity in children may increase the risk of HBP in their late adolescence. If an obese child restores normal weight before late adolescence, the risk of HBP may reduce.

Effect of radiomics from different virtual monochromatic images in dual-energy spectral CT on the WHO/ISUP classification of clear cell renal cell carcinoma

AIM

To investigate the effect of radiomics obtained from different virtual monochromatic images (VMIs) in dual-energy spectral computed tomography (CT) on the World Health Organization/International Association for Urological Pathology (WHO/ISUP) classification of clear cell renal cell carcinoma (ccRCC).

MATERIALS AND METHODS

A retrospective study of 99 ccRCC patients who underwent contrast-enhanced dual-energy CT was undertaken. ccRCC was confirmed at surgery or biopsy and graded according to the WHO/ISUP pathological grading criteria as low grade (n=68, grade I and II) or high grade (n=31, grade III and IV). Radiomics risk scores (RRSs) for differentiating high and low grades of ccRCC were constructed from 11 sets of VMI in (40-140 keV, 10 keV interval) the cortical phase. Receiver operating characteristic (ROC) curves were drawn and the area under the curves (AUCs) was calculated to evaluate the discriminatory power of RRS for each VMI. The Hosmer-Lemeshow test was used to evaluate the goodness-of-fit of each model and the decision curve was used to analyse its net benefit to patients.

RESULTS

The AUC values for distinguishing low-from high-grade ccRCC with RRS of 40-140 keV VMIs were all >0.920. The Hosmer-Lemeshow test showed that the p-values of RRS of VMIs were >0.05, suggesting good fits. In the decision curve analysis, RRS from the 40-140 keV VMIs had similar decision curves and provided better net benefits than considering all patients either as high-grade or low-grade.

CONCLUSIONS

The RRS obtained from multiple VMIs in dual-energy spectral CT have high diagnostic efficiencies for distinguishing between low- and high-grade ccRCC with no significant differences between different VMIs.

[Research progress in studies on tooth development based on diphyodont mammals]

For decades, the molecular and cellular mechanisms that govern tooth development have been extensively investigated. However, most of the studies are based on mice, whose teeth are quite different from human teeth in morphological and developmental aspects. Mice are not the ideal model for understanding the development of permanent teeth as they have only one set of dentition. Thus, using of diphyodont mammals is a better model to study the deciduous and permanent tooth development and to understand the process of tooth replacement. Several diphyodont mammal models have been established including minipig, ferret, house shrew and rabbit. Studies based on the diphyodont mammals have characterized the morphological changes involved in tooth replacement and molecular mechanisms of tooth replacement. However, few developmental stages were studied on ferret due to the presence of seasonal estrus and the difficulty to obtain ferret embryos at the correct stage. The house shrew is limited as a model because their deciduous tooth germs become vestigial in the embryonic period. The main disadvantage of the rabbit is an incomplete dentition with the lack of canines. Compared to the above mentioned animal models, the miniature pig has proven to be a valuable animal model for diphyodont development due to its dentition similarities, including the morphology, number and size of teeth, to human's, and particularly its heterodont dentition consisting of incisors, canines, premolars and molars. The present article reviews the current knowledge on the development of the primary and successional teeth in minipig modle and briefly summarizes the studies based on other diphyodont mammal models.

Natural killer cell-derived exosome-entrapped paclitaxel can enhance its anti-tumor effect

OBJECTIVE

To study the effectiveness of natural killer cell-derived exosome (NK-Exos)-entrapped paclitaxel (PTX-NK-Exos) in enhancing its anti-tumor effect.

MATERIALS AND METHODS

The NK-Exos were isolated through ultra-high-speed centrifugation, and the PTX-NK-Exos system was constructed via electroporation. The morphology, particle size, Zeta potential and entrapment rate of PTX-NK-Exos were evaluated using transmission electron microscope (TEM), dynamic light scattering (DLS), Western blotting and high-performance liquid chromatography (HPLC), respectively. The uptake of Exos in human breast cancer MCF-7 cells was observed under a laser confocal microscope. Moreover, the effect of PTX-NK-Exos on MCF-7 cell viability was determined through methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and 4',6-diamidino-2-phenylindole (DAPI) staining. The effects of PTX-NK-Exos on messenger ribonucleic acid (mRNA) and protein expressions of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax) and Caspase-3 in MCF-7 cells were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting, respectively.

RESULTS

The NK-Exos were successfully isolated via ultra-high-speed centrifugation, and they had uniform particle size and high expression of markers for Exos. MCF-7 cells could take up Exos. The PTX-NK-Exos drug delivery system was successfully prepared using electroporation. In PTX group and NK-Exos group, the proliferation of MCF-7 cells declined, the nuclear apoptosis was evident and the apoptosis rate of MCF-7 cells rose compared with those in Control group. In PTX group and PTX-NK-Exos group, the migration of MCF-7 cells declined compared with that in Control group. According to the results of qRT-PCR and Western blotting, PTX-NK-Exos exerted an anti-tumor effect through inducing the up-regulation of Bax and Caspase-3 in the apoptotic signaling pathway in tumor cells.

CONCLUSIONS

Exos isolated through ultra-high-speed centrifugation can be used to prepare the PTX-NK-Exos drug delivery system through electroporation. Drug-loaded Exos can effectively inhibit proliferation and induce apoptosis of tumor cells, thereby exerting an anti-tumor effect.

LINC00511 can promote the proliferation, migration and invasion of esophageal cancer cells through regulating microRNA-150-5p

OBJECTIVE

The aim of this study was to investigate the potential role of LINC00511 in esophageal cancer (ECa), and to explore its underlying mechanism through in vitro cell experiments.

PATIENTS AND METHODS

LINC00511 expression in ECa was analyzed by GEPIA database and verified by real-time fluorescence quantitative polymerase chain reaction (qPCR). The bioinformatics website was used to analyze the miRNAs that can bind to LINC00511, and the regulatory relationship between them was verified through Luciferase assay, qPCR as well as Western blotting analysis. Then, the impacts of LINC00511 and microRNA-150-5p on the proliferation or invasiveness of ECa cell lines Kyse30 and ECA109 were investigated by cell counting kit-8 (CCK-8) test and transwell experiment, respectively. Meanwhile, cell cycle and apoptosis were detected by flow cytometry.

RESULTS

Analysis results of the GEPIA database revealed that LINC00511 had a significant high expression in ECa tissue samples in comparison with normal control ones, which is consistent with qPCR results. Meanwhile, a significant negative correlation was found between LINC00511 and microRNA-150-5p. In brief, LINC00511 was able to bind to microRNA-150-5p and inhibited its expression. Besides, overexpression of LINC00511 enhanced ECa cell proliferation and migration, accelerated cell cycle, and suppressed cell apoptosis, while transfection with microRNA-150-5p mimics caused the opposite effects.

CONCLUSIONS

This study shows for the first time that LINC00511 modulates the progression of ECa by binding to microRNA-150-5p.

Lrp6 Dynamic Expression in Tooth Development and Mutations in Oligodontia

Genes associated with the WNT pathway play an important role in the etiology of tooth agenesis. Low-density lipoprotein receptor-related protein 6 encoding gene (LRP6) is a recently defined gene that is associated with autosomal dominant inherited tooth agenesis. Here, we aimed to identify novel LRP6 mutations in patients with tooth agenesis and investigate the significance of Lrp6 during tooth development. Using whole-exome sequencing, we identified 4 novel LRP6 heterozygous mutations (c.2292G>A, c.195dup, c.1095dup, and c.1681C>T) in 4 of 77 oligodontia patients. Notably, a patient who carried a nonsense LRP6 mutation (c.2292G>A; p.W764*) presented a hypohidrotic ectodermal dysplasia phenotype. Preliminary functional studies, including bioinformatics analysis and TOP-/FOP-flash reporter assays, demonstrated that the activation of WNT/β-catenin signaling was compromised as a consequence of LRP6 mutations. RNAscope in situ hybridization revealed dynamic and special changes of Lrp6 expression during murine tooth development from E11.5 to E16.5. It was noteworthy that Lrp6 was specifically expressed in the epithelium at E11.5 to E13.5 but was expressed in both dental epithelium and dental papilla from E14.5 and persisted in both tissues at later stages. Our study broadens the mutation spectrum of human tooth agenesis and is the first to identify a LRP6 mutation in patients with hypohidrotic ectodermal dysplasia and reveal the dynamic expression pattern of Lrp6 during tooth development. Information from this study is conducive to understanding the functional significance of Lrp6 on the biological process of tooth development.

The change of serum serotonin levels between acute coronary syndrome and chronic stable angina undergoing percutaneous coronary intervention

Background

Activated platelets release serotonin (5-hydroxytryptamine, 5HT) causing vasoconstriction and aggregation of platelets in patients with acute coronary syndrome (ACS). It can lead to undergo percutaneous coronary intervention (PCI). We investigated the serial changes of serotonin level in patients with ACS and chronic stable angina (CSA) treated with PCI.

Methods

From July 2009 to April 2010, 123 consecutive patients who have undergone PCI for either ACS (n=63) or CSA (n=60) were enrolled. After the loading dose of aspirin 300mg and clopidogrel 600mg before PCI, maintenance once daily dose of 100mg and 75mg have been given from the day after PCI in all patients. Serum serotonin level (SERO) were serially measured at baseline, pre-, post-PCI, 90 min, 6 hours, 12 hours, 24 hours and 48 hours to compare between ACS and CSA groups. All demographic, biochemical variables, and clinical events were also collected for comparison in each group.

Results

SERO at post-PCI (55.2±120.0 vs 20.1±24.0, p=0.03) and peak level (94.0±170.9 vs 38.8±72.3, p=0.02) were significantly higher in ACS group. SERO after 90 min (34.4±66.1 vs 28.7±38.2, p=0.8), 6 hours (23.9±38.3 vs 10.1±10.0, p=0.34), 24 hours (55.8±108.5 vs 37.2±88.2, p=0.39) and 48 hours (43.5±122.9 vs 25.2±65.5, p=0.53) tended to be higher in ACS group than CSA group without statistical significance. SERO rebounded at 24 hours post-PCI and dropped at 48 hours.

Conclusions

SERO was more elevated in patients with ACS than those with CSA undergoing PCI, suggesting the need for more potent and sustained platelet inhibition particularly in ACS patients. SERO might be considered as a substitute marker of platelet activation. Triple antiplatelet therapy including selective serotonin receptor antagonist on top of aspirin and clopidogrel could be as an option for ACS patients undergoing PCI

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Hallym University Research Fund 2017 (HURF-2017-84)