Spatial-temporal variations of forest and grassland phenology in the Yellow River Basin during 2000-2018.

The study of vegetation phenology is of great significance for understanding global climate change. The Yellow River basin has a wide spatial range and a complex ecological environment. The phenological characteristics of forest and grassland need further clarification. Based on the MODIS-EVI data from 2000 to 2018, we extracted the phenology of forest and grassland in the Yellow River basin using piecewise logistic and double logistic phenological models with the corresponding curvature change extremum method and derivative method, respectively. The temporal and spatial variations of phenological parameters were analyzed. The start of growing season (SOS) was at 90-165 day of year (DOY), and gradually delayed from southeast to northwest. The increase of 100 m elevation delayed SOS 0.94 d, and the SOS of forest was earlier than that of grassland. The end of growing season (EOS) was at 270-315 DOY, which delayed from west to southeast. For every 100 m increase in altitude, the EOS advanced 0.63 d, with EOS of forest being later than that of grassland. The length of growing season (LOS) was 110-230 d, which shortened gradually from southeast to northwest. The LOS of forest was larger than that of grassland. During the study, SOS showed an advance trend from 2000 to 2018 with a rate of 4.1 d·(10 a)-1, and the proportion of spatial advance area was 73.2%. There was an obvious advance in the central part of the basin. EOS generally showed a significant postponement trend with a rate of 2.3 d·(10 a)-1, and the proportion of spatially delayed area was 63.4%, the phenological advance and delay of forest was less stronger than that of grassland. LOS showed a significant prolongation trend with a rate of 6.4 d·(10 a)-1, and the proportion of spatial extension was 71.8%. The piecewise Logistic and double Logistic phenological models and the corresponding curvature extremum method and derivative method were suitable for the extraction of natural vegetation in the Yellow River Basin. The overall LOS of forest and grassland showed a prolonging trend, which was shortened with the increases of altitude. The LOS of forest was longer than that of grassland in the study area.

[Brachydactyly and the molecular mechanisms of digit formation].

Brachydactyly (BD) is a type of hand/foot malformation caused by the abnormal shortening or missing phalanges and/or metacarpals/metatarsals. BD most often occurs as an isolated trait, but can also occur as part of complex malformation syndromes. According to the patterns of affected digits, isolated BD can be divided into five groups: BDA, BDB, BDC, BDD, and BDE with individual subtypes. As an important molecular disease family, the pathogenic genes and molecular mechanisms of most isolated BD forms and some complicated syndromes are elucidated. Although BDs are highly diversified in phenotypes, at the molecular levels these pathogenic genes mainly affect several important signaling pathways: Hedgehog, NOTCH, WNT and BMP. These pathways form a complex signaling network and play different roles in different stages of the digit and joint development, in which BMP signaling pathway occupies a central position. Based on the current classification of BDs, this review summarizes the latest progress in the pathogenesis of BDs and the signaling pathways involved. The purpose of this review is to explore the molecular mechanisms of digit formation, which will provide references for the clinical diagnosis of BD, and the understanding of molecular mechanism of human bone development.

Screening and analysis of key active constituents in Guanxinshutong capsule using mass spectrum and integrative network pharmacology.

Guanxinshutong capsule (GXSTC) is an effective and safe traditional Chinese medicine used in the treatment of cardiovascular diseases (CVDs) for many years. However, the targets of this herbal formula and the underlying molecular mechanisms of action involved in the treatment of CVDs are still unclear. In the present study, we used a systems pharmacology approach to identify the active ingredients of GXSTC and their corresponding targets in the calcium signaling pathway with respect to the treatment of CVDs. This method integrated chromatographic techniques, prediction of absorption, distribution, metabolism, and excretion, analysis using Kyoto Encyclopedia of Genes and Genomes, network construction, and pharmacological experiments. 12 active compounds and 33 targets were found to have a role in the treatment of CVDs, and four main active ingredients, including protocatechuic acid, cryptotanshinone, eugenol, and borneol were selected to verify the effect of (GXSTC) on calcium signaling system in cardiomyocyte injury induced by hypoxia and reoxygenation. The results from the present study revealed the active components and targets of GXSTC in the treatment of CVDs, providing a new perspective to enhance the understanding of the role of the calcium signaling pathway in the therapeutic effect of GXSTC.

Phosphodiesterase 4 Inhibitor Roflumilast Protects Rat Hippocampal Neurons from Sevoflurane Induced Injury via Modulation of MEK/ERK Signaling Pathway.

BACKGROUND/AIMS: Sevoflurane, a commonly used volatile anesthetic, recently has been found has neurotoxicity in the central nervous system of neonatal rodents. This study aimed to reveal whether phosphodiesterase 4 (PDE-4) inhibitor roflumilast has protective functions in sevoflurane-induced nerve damage. METHODS: Hippocampal neurons were isolated from juvenile rats, and were exposed to sevoflurane with or without roflumilast treatment. Cell viability and apoptosis were respectively assessed by CCK-8 and flow cytometry. Western blot analysis was performed to detect the protein expressions of apoptosis-related factors, and core factors in MEK/ERK and mTOR signaling pathways. RESULTS: Toxic effects of sevoflurane on hippocampal neurons were observed, as cell viability was reduced, apoptotic cell rate was increased, Bcl-2 was down-regulated, and Bax, cleaved caspase-3 and -9 were up-regulated after 1% sevoflurane exposure for 16 h. Sevoflurane exhibited a temporarily (less than 16 h) inhibitory effect on MEK/ERK pathway, but has no impact on mTOR pathway. Roflumilast promoted the release of cAMP and down-regulated the protein expression of PDE-4. Roflumilast (1 µM) alone has no impact on viability and apoptosis of hippocampal neurons. However, roflumilast increased cell viability and deceased apoptosis in sevoflurane-injured neurons. Besides, roflumilast could recover sevoflurane-induced deactivation of MEK/ERK pathway. CONCLUSION: To conclude, this study demonstrated a neuroprotective role of roflumilast in sevoflurane-induced nerve damage. Roflumilast promoted hippocampal neurons viability, and reduced apoptosis possibly via modulation of MEK/ERK signaling pathway.

Electroacupuncture alleviates surgery-induced cognitive dysfunction by increasing α7-nAChR expression and inhibiting inflammatory pathway in aged rats.

Postoperative cognitive dysfunction (POCD) is a common disorder of cognitive functions in aged patients following anesthesia and surgery. α7-nicotinic acetylcholine receptors (α7-nAChR) plays a regulatory role in cognitive processes and is involved in cognitive deficits. This study aims to observe the effect of electroacupuncture (EA) on the cognitive function in aged POCD rats, and its regulation on expressions of hippocampal α7-nAChR and proinflammatory factors. Ninety healthy Sprague-Dawley male aged rats were randomly divided into three groups (each n=30): control group (sham operation), model group (partial hepatectomy), and electroacupuncture (EA) group. The cognitive function was detected by Morris water-maze test, and the changes of hippocampal expressions of α7-nAChR, tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were detected by immunohistochemical method. Our results showed that compared with the model group, the EA group had significantly shorter escape latency and decreased crossing platform times at 1d, 3d and 7d after operation (P<0.05). α7-nAChR positive neurons in the hippocampus decreased and TNF-α and IL-1ß positive neurons increased on postoperative days 1, 3 and 7. Compared with the model group, the α7-nAChR positive neurons were increased and TNF-α and IL-1ß positive neurons were decreased in the EA group at the same time points (P<0.05). In conclusion, the electroacupuncture regulation can improve the learning and memory abilities in POCD rats, and its mechanism may be related to upregulation of α7-nAChR and downregulation of TNF-α and IL-1ß in hippocampus.