Comparative skin histological and transcriptomic analysis of Rana kukunoris with two different skin colors.

This study compares the skin structures of Rana kukunoris with two different skin colors living in the same area of Haibei in the Northeastern Qinghai-Tibet Plateau. The skin thickness of the khaki R. kukunoris was significantly greater than that of the brown R. kukunoris (P < 0.01), and significantly more mucous and granular glands were present on the dorsal skin of the khaki frog (P < 0.05). Meanwhile, the melanocytes on the dorsal skin of the brown frog were significantly larger than those on the khaki one (P < 0.05). Morphological changes in the expansion and aggregation of melanocytes seemed to deepen the skin color of R. kukunoris. Moreover, transcriptome sequencing identified tyrosine metabolism, melanogenesis, and riboflavin metabolism as the main pathways involved in melanin formation and metabolism in brown R. kukunoris. TYR, MC1R was upregulated as the skin color of R. kukunoris was deepened and contributed to melanin production and metabolism. In contrast, the khaki frog had significantly more upregulated genes and metabolic pathways related to autoimmunity. The khaki frog appeared to defend against ultraviolet (UV) radiation-induced damage by secreting mucus and small molecular peptides, whereas the brown frog protected itself by distributing a large amount of melanin. Hence, the different skin colors of R. kukunoris might represent different adaptation strategies for survival in the intense UV radiation environment of the Qinghai-Tibet Plateau.

Five new and noteworthy species of Epidendroideae (Orchidaceae) from southwestern China based on morphological and phylogenetic evidence.

Five new orchid species from southwestern China's Yunnan Province and the Tibetan Autonomous Region, Neottialihengiae, Neottiachawalongensis, Papilionanthemotuoensis, Gastrochiluslihengiae, and Gastrochilusbernhardtianus, are described and illustrated. To confirm their identities, and to resolve phylogenetic relationships, we sequenced the complete plastomes of these taxa with their congeneric species, adding new plastomes of three Neottia species, two Papilionanthe species and nine Gastrochilus species. Combined with published plastid sequences, our well-resolved phylogeny supported the alliance of N.lihengiae with the the N.grandiflora + N.pinetorum clade. Neottiachawalongensis is now sister to N.alternifolia, while P.motuoensis is closely related to P.subulata + P.teres. Conversely, phylogenetic analyses based on complete plastomes and plastid sequences showed inconsistent relationships among taxa in the genus Gastrochilus, but the two new species, G.lihengiae and G.bernhardtianus were supported by all datasets.

[Effect of electroacupuncture on transforming growth factor-ß1 and renal tubular epithelial mesenchymal transformation in renal tissue of spontaneously hypertensive rats].

OBJECTIVE: To observe the effects of electroacupuncture (EA) on renal fibrosis, the expression of transforming growth factor-ß1 (TGF-ß1) and epithelial mesenchymal transition (EMT) marker proteins in renal tissue of spontaneously hypertensive rats (SHR), so as to explore the underlying mechanism on EA alleviating hypertensive renal impairment. METHODS: Twenty-four male SHR were randomly divided into model group, losartan group and EA group, with 8 rats in each group, and eight male Wistar-Kyoto rats were taken as the normal group. Rats in the losartan group received gavage of losartan potassium solution (3 mg/mL, 30 mg·kg-1·d-1),once every other day for 12 weeks. Rats in the EA group received EA stimulation at bilateral "Shenshu" (BL23) and "Geshu" (BL17) (2 Hz/15 Hz, 1.0 mA), 15 min each time, once every other day for 12 weeks. The systolic blood pressure of caudal artery was measured before, and 4, 8 and 12 weeks after the intervention. The 24-hour urinary protein was measured before, and 6 and 12 weeks after the intervention. Histopathological changes of the left renal tissue were observed under light mircoscope after H.E. stain. Extracellular matrix (ECM) in renal tissues was observed after periodate Schiff staining. Basement membrane and collagen fibers were observed after Masson staining with collagen volume fraction (CVF) evaluated. The expression of TGF-ß1 mRNA in the right renal was detected by real-time fluorescence quantitative PCR. The expression of TGF-ß1 and EMT marker E-cadherin, α-SMA and fibronectin (FN) proteins in the left renal tissue was measured by immunohistochemistry. RESULTS: In the model group, irregular arrangement of nephrocytes, renal tubule atrophy, lumen stenosis, ECM hyperplasia and deposition, scar and sclerosis were observed, which were relatively milder in the EA and losartan groups. Compared with the normal group, tubulointerstitium CVF, systolic blood pressure of caudal artery before, and at 4, 8 and 12 weeks after the intervention, 24-hour urinary protein before, and at 6 and 12 weeks after the intervention, the expression of TGF-ß1 mRNA, area of TGF-ß1, α-SMA and FN positive staining in renal tissues were significantly increased (P<0.01), while the area of E-cadherin positive staining was significantly decreased (P<0.01) in the model group. Compared with the model group, tubulointerstitium CVF, systolic blood pressure of caudal artery at 4, 8 and 12 weeks after the intervention, 24-hour urinary protein at 6 and 12 weeks after the intervention, the expression of TGF-ß1 mRNA, area of TGF-ß1, α-SMA and FN positive staining in renal tissues were significantly decreased (P<0.01，P<0.05), while area of E-cadherin positive staining was significantly increased (P<0.01) in the losartan and EA groups. Compared with the losartan group, the area of E-cadherin was conside-rately increased (P<0.01), while the area of α-SMA protein decreased (P<0.01) in the EA group. CONCLUSION: EA could effectively alleviate hypertension and renal interstitial fibrosis in SHR, the mechanism of which may be related to its function in reducing the expression of TGF-ß1 and inhibiting EMT in renal tissue.

Intercellular communication in the tumour microecosystem: Mediators and therapeutic approaches for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC), one of the most common tumours worldwide, is one of the main causes of mortality in cancer patients. There are still numerous problems hindering its early diagnosis, which lead to late patients receiving treatment, and these problems need to be solved urgently. The tumour microecosystem is a complex network system comprising seven parts: the hypoxia niche, immune microenvironment, metabolic microenvironment, acidic niche, innervated niche, mechanical microenvironment, and microbial microenvironment. Intercellular communication is divided into direct contact and indirect communication. Direct contact communication includes gap junctions, tunneling nanotubes, and receptor-ligand interactions, whereas indirect communication includes exosomes, apoptotic vesicles, and soluble factors. Mechanical communication and cytoplasmic exchange are further means of intercellular communication. Intercellular communication mediates the crosstalk between the tumour microecosystem and the host as well as that between cells and cell-free components in the tumour microecosystem, causing changes in the tumour hallmarks of the HCC microecosystem such as changes in tumour proliferation, invasion, apoptosis, angiogenesis, metastasis, inflammatory response, gene mutation, immune escape, metabolic reprogramming, and therapeutic resistance. Here, we review the role of the above-mentioned intercellular communication in the HCC microecosystem and discuss the advantages of targeted intercellular communication in the clinical diagnosis and treatment of HCC. Finally, the current problems and prospects are discussed.

Phylogenomics and evolutionary history of Oreocnide (Urticaceae) shed light on recent geological and climatic events in SE Asia.

Climate change and geological events have long been known to shape biodiversity, implying that these can likewise be viewed from a biological perspective. To study whether plants can shed light on this, and how they responded to climate change there, we examined Oreocnide, a genus widely distributed in SE Asia. Based on broad geographic sampling with genomic data, we employed an integrative approach of phylogenomics, molecular dating, historical biogeography, and ecological analyses. We found that Oreocnide originated in mainland East Asia and began to diversify ∼6.06 Ma, probably in response to a distinct geographic and climatic transition in East Asia at around that time, implying that the last important geological change in mainland SE Asia might be 1 Ma older than previously suggested. Around six immigration events to the islands of Malesia followed, indicating that immigration from the mainland could be an underestimated factor in the assembly of biotic communities in the region. Two detected increases of diversification rate occurred 3.13 and 1.19 Ma, which strongly implicated climatic rather than geological changes as likely drivers of diversification, with candidates being the Pliocene intensification of the East Asian monsoons, and Pleistocene climate and sea level fluctuations. Distribution modelling indicated that Pleistocene sea level and climate fluctuations were inferred to enable inter-island dispersal followed by allopatric separation, underpinning radiation in the genus. Overall, our study, based on multiple lines of evidence, linked plant diversification to the most recent climatic and geological events in SE Asia. We highlight the importance of immigration in the assembly and diversification of the SE Asian flora, and underscore the utility of plant clades, as independent lines of evidence, for reconstructing recent climatic and geological events in the SE Asian region.

Spatiotemporal maintenance of flora in the Himalaya biodiversity hotspot: Current knowledge and future perspectives.

Mountain ecosystems support a significant one-third of all terrestrial biodiversity, but our understanding of the spatiotemporal maintenance of this high biodiversity remains poor, or at best controversial. The Himalaya hosts a complex mountain ecosystem with high topographic and climatic heterogeneity and harbors one of the world's richest floras. The high species endemism, together with increasing anthropogenic threats, has qualified the Himalaya as one of the most significant global biodiversity hotspots. The topographic and climatic complexity of the Himalaya makes it an ideal natural laboratory for studying the mechanisms of floral exchange, diversification, and spatiotemporal distributions. Here, we review literature pertaining to the Himalaya in order to generate a concise synthesis of the origin, distribution, and climate change responses of the Himalayan flora. We found that the Himalaya supports a rich biodiversity and that the Hengduan Mountains supplied the majority of the Himalayan floral elements, which subsequently diversified from the late Miocene onward, to create today's relatively high endemicity in the Himalaya. Further, we uncover links between this Miocene diversification and the joint effect of geological and climatic upheavals in the Himalaya. There is marked variance regarding species dispersal, elevational gradients, and impact of climate change among plant species in the Himalaya, and our review highlights some of the general trends and recent advances on these aspects. Finally, we provide some recommendations for conservation planning and future research. Our work could be useful in guiding future research in this important ecosystem and will also provide new insights into the maintenance mechanisms underpinning other mountain systems.

Non-Noble-Metal Metal-Organic-Framework-Catalyzed Carboxylative Cyclization of Propargylic Amines with Atmospheric Carbon Dioxide under Ambient Conditions.

The coupling reaction of propargylic amines and carbon dioxide (CO2) to synthesize 2-oxazolidinones is an important reaction in industrial production, and yet harsh reaction conditions and noble-metal catalysts are often required to achieve high product yields. Herein, one novel noble-metal-free three-dimensional framework, [Mg3Cu2I2(IN)4(HCOO)2(DEF)4]n (1), assembled by magnesium and copper clusters was synthesized and applied to this reaction. Compound 1 displays excellent solvent stability. Importantly, 1, acting as heterogeneous catalyst, can highly catalyze the cyclization of propargylic amines with CO2 under atmospheric pressure at room temperature, which can be recycled at least five times without an obvious decrease of the catalytic activity. NMR spectroscopy, coupled with 13C-isotope- and deuterium-labeling experiments, clearly clarifies the mechanism of this catalytic system: CO2 was successfully captured and converted to the product of 2-oxazolidinones, the C≡C bond of propargylic amines can be effectively activated by 1, and proton transfer was involved in the reaction process. Density functional theory calculations are further conducted to uncover the reaction path and the crucial role of compound 1 during the reaction.

A Porous Copper-Organic Framework Assembled by [Cu12] Nanocages: Highly Efficient CO2 Capture and Chemical Fixation and Theoretical DFT Calculations.

A new porous copper-organic framework assembled from 12-nuclear [Cu12] nanocages {[Cu2(L4-)(H2O)2]·4DMA·2H2O}n (1) (H4L = 5,5'-(butane-1,4-diyl)-bis(oxy)-diisophthalic acid) was successfully prepared and structurally characterized. Compound 1 feathering of a 3D framework with two types of 1D nanotubular channels and a large specific surface area can effectively enrich various harmful dyes. Additionally, due to the carbon dioxide (CO2) interactions with open Cu(II) sites and the electron-rich ether oxygen atoms of ligand in 1, it exhibits a highly selective CO2 uptake. Interestingly, 1 can effectively catalyze the cycloaddition reaction of CO2 with various epoxides under mild conditions, which is ascribed to the Lewis acid Cu(II) sites in the framework of 1. Importantly, 1 acting as a heterogeneous catalyst can be recycled at least 10 times without an obvious loss of catalytic activity, and the CO2 cycloaddition mechanism was further uncovered by density functional theory (DFT) calculations. This study can greatly enrich the MOF catalysts system of CO2 conversion and also provide a valuable guidance for the design of efficient MOFs catalysts.

Up-and-down shaker-assisted ionic liquid-based dispersive liquid-liquid microextraction of benzophenone-type ultraviolet filters.

Sun protection is an important part of our lives. UV filters are widely used to absorb solar radiation in sunscreens. However, excess UV filters constitute persistent groups of organic micropollutants present in the environment. An environmentally friendly ionic-liquid-based up-and-down shaker-assisted dispersive liquid-liquid microextraction device combined with ultra-performance liquid chromatography coupled with photodiode-array detection has been developed to preconcentrate three UV filters (benzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone) from field water samples. In this method, the optimal conditions for the proposed extraction method were: 40 µL [C8MIM][PF6 ] as extraction solvent and 200 µL methanol as disperser solvent were used to extract the UV filters. After up-and-down shaking for 3 min, the aqueous solution was centrifuged at 5000 rpm speed, then using microtube to collect the settled extraction solvent and using ultra-performance liquid chromatography for further analysis. Quantification results indicated that the linear range was 2-1000 ng/mL. The LOD of this method was in the range 0.2-1.3 ng/mL with r(2) ≥ 0.9993. The relative recovery in studies of different types of field water samples was in the range 92-120%, and the RSD was 2.3-7.1%. The proposed method was also applied to the analysis of field samples.