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The Torrent frogs of the genus Amolops are widely distributed in Nepal and northern India eastwards to southern China and southwards to Malaysia. The genus currently contains 84 species. Previous studies indicated underestimated species diversity in the genus. In the context, a new species occurring from the mountains in the northwestern Guizhou Province, China is found and described based on morphological comparisons and molecular phylogenetic analyses, Amolops dafangensis sp. nov. Phylogenetic analyses based on DNA sequences of the mitochondrial 16S rRNA and COI genes supported the new species as an independent lineage. The uncorrected genetic distances between the 16S rRNA and COI genes in the new species and its closest congener were 0.7% and 2.6%, respectively, which are higher than or at the same level as those among many pairs of congeners. Morphologically, the new species can be distinguished from its congeners by a combination of the following characters: body size moderate (SVL 43.2–46.8 mm in males); head length larger than head width slightly; tympanum distinct, oval; vocal sacs absent; vomerine teeth present; dorsolateral folds weak formed by series of glands; nuptial pads present on the base of finger I; heels overlapping when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level far beyond the tip of the snout when leg stretched forward.

This study compared collagens from cold-water and warm-water fish for their structural, rheological, and functional properties, and explored their potential applications, aiming to realize the high-value utilization of marine biological resources. To this end, chum salmon skin collagen (CSSC) and Nile tilapia skin collagen (NTSC) were both successfully extracted. Collagens from the two species had different primary and secondary structures, with NTSC having a higher molecular weight, imino acid content, and α-helices and β-turns content. The denaturation temperatures were 12.01 °C for CSSC and 31.31 °C for NTSC. CSSC was dominated by viscous behavior and its structure varied with temperature, while NTSC was dominated by elastic behavior and its structure remained stable with temperature. Both collagens had good oil holding capacity, foaming capacity, and emulsifying activity, but NTSC had better water holding capacity and foaming and emulsifying stability. Their different properties make CSSC more suitable for the preservation of frozen and chilled foods and the production of sparkling beverages, and give NTSC greater potential in biofunctional materials and solid food processing.

Objective To investigate the effect of recombinant Treponema pallidum protein Tp47 (rTpp47) on the expression of uPA by THP-1 macrophages and on the permeability of human umbilical vein/vascular endothelial cells(HUVECs). Methods THP-1 cells were stimulated with rTpp47 for 24 hours and then the culture supernatant and THP-1 cells were collected respectively. The expression of urokinase-type plasminogen activator (uPA) in THP-1 cells was detected by ELISA and Western blot. After stimulation of HUVECs monolayers by THP-1 cell culture supernatant, FITC-dextran was used to evaluate the permeability of HUVECs. Western blot method was used to observe the effect of uPA on the expression of tight junction protein claudin-5 of HUVECs and the protein kinase C(PKC) signaling pathway of THP-1 cells stimulated by rTpp47. Results The synthesis and secretion of uPA of THP-1 cells stimulated by rTpp47 were significantly higher than those in the control group(P＜0.05, P＜0.001). When HUVECs were stimulated by the THP-1 cell supernatant for 12 hours and 24 hours, the relative permeability of vascular endothelial cells in the experimental group was significantly higher than the control group (P＜0.05 for 12 hours and P＜0.000 1 for 24 hours). Amiloride, the synthetic inhibitor of uPA, significantly inhibited the uPA expression and secretion of THP-1 cells stimulated by rTpp47 (P＜0.0001), alleviated the inhibition effect of rTpp47 on claudin-5 expression of HUVECs (P＜0.05), and significantly suppressed PKC phosphorylation(P＜0.05) in THP-1 cells induced by rTpp47. Conclusions The rTpp47 can stimulate the synthesis and secretion of uPA in THP-1 cells through a potential mechanism of activating PKC signaling pathway and uPA may increase the permeability of vascular endothelial cells.

Understanding the response of soil respiration to global warming in agro-ecosystem is crucial for simulating terrestrial carbon (C) cycle. We conducted an infrared warming experiment under conventional tillage (CT) and no-tillage (NT) farmland for winter wheat and summer maize rotation system in North China Plain (NCP). Treatments include CT with and without warming (CTW and CTN), NT with and without warming (NTW and NTN). The results indicated that warming had no significant effect on soil moisture in irrigated farmland of NCP (P>0.05). The elevated average soil temperature of 1.1–1.6°C in crop growing periods could increase annual soil CO2 emission by 10.3% in CT filed (P>0.05), but significantly increase it by 12.7% in NT field (P