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Profile sampling, which causes missing or overlapping horizons, has been generally used while studying loess stratigraphy and paleoclimate. Conversely, drill sampling of thick loess can provide a relatively complete and actual record of the Quaternary climate and environmental changes. Here, paleomagnetic chronological analysis and particle size and magnetic susceptibility analyses were performed to accurately reveal the loess stratigraphy characteristics of Luochuan loess tableland in Fu County, Shaanxi Province, China. The FX core revealed that the Quaternary loess layer was 167.03 m thick and consisted of 33 layers of developed loess/paleosol sequences and 37 loess/paleosol assemblages. The paleosol horizons indicated relatively warm and humid climatic period, while loess/sand reflected cold and arid climate. Since 2.6 Ma, the climate of the region has undergone 37 warm and cold cycles trending toward an increasingly dry and cold climate. During this time, 10 paleoclimate cycles occurred during 2.6–1.6 Ma, 15 climate cycles occurred during 1.6–0.8 Ma, and 12 loess–paleosol cycles have occurred from 0.8 Ma to the present day. Our study provides a basis for accurately and comprehensively interpreting the paleoclimate and paleoenvironment during loess deposition formation.

The safety and efficacy of anti-diabetic drugs are critical for maximizing the beneficial impacts of well-controlled blood glucose on the prognosis of individuals with COVID-19 and pre-existing type 2 diabetes (T2D). Metformin is the most commonly prescribed first-line medication for T2D, but its impact on the outcomes of individuals with COVID-19 and T2D remains to be clarified. Our current retrospective study in a cohort of 1,213 hospitalized individuals with COVID-19 and pre-existing T2D indicated that metformin use was significantly associated with a higher incidence of acidosis, particularly in cases with severe COVID-19, but not with 28-day COVID-19-related mortality. Furthermore, metformin use was significantly associated with reduced heart failure and inflammation. Our findings provide clinical evidence in support of continuing metformin treatment in individuals with COVID-19 and pre-existing T2D, but acidosis and kidney function should be carefully monitored in individuals with severe COVID-19.

Statins are lipid-lowering therapeutics with favorable anti-inflammatory profiles and have been proposed as an adjunct therapy for COVID-19. However, statins may increase the risk of SARS-CoV-2 viral entry by inducing ACE2 expression. Here, we performed a retrospective study on 13,981 patients with COVID-19 in Hubei Province, China, among which 1,219 received statins. Based on a mixed-effect Cox model after propensity score-matching, we found that the risk for 28-day all-cause mortality was 5.2% and 9.4% in the matched statin and non-statin groups, respectively, with an adjusted hazard ratio of 0.58. The statin use-associated lower risk of mortality was also observed in the Cox time-varying model and marginal structural model analysis. These results give support for the completion of ongoing prospective studies and randomized controlled trials involving statin treatment for COVID-19, which are needed to further validate the utility of this class of drugs to combat the mortality of this pandemic.

Abstract This study aimed to decipher the effect of glycoprotein nonmetastatic melanoma protein B (GPNMB) on neonatal hypoxic–ischemic encephalopathy (NHIE) and its potential molecular mechanism. The hypoxic–ischemic (HI) model was established in 7‐day‐old rats, and then, Zea‐Longa scores and Nissl staining were performed to measure brain damage post‐HI. In addition, gene sequencing was used to detect the differential expression genes (DEGs), and then, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases were used to determine the function of DEGs. Furthermore, an oxygen–glucose deprivation (OGD) model was developed in SY5Y cells and human fetal neurons, and then, the level of GPNMB was verified by quantitative real‐time polymerase chain reaction. In addition, methyl thiazolyl tetrazolium and cell counting kit‐8 assays were applied after GPNMB interference. Finally, the alternative splicing of GPNMB expression was analyzed using Splice Grapher software. The results indicated that HI induced marked neurological impairment and neuron injury in rats. Also, GPNMB was the most obviously upregulated gene in DEGs. Additionally, GPNMB was upregulated significantly in SY5Y and fetal neurons after OGD, and GPNMB‐si promoted an increase in cell viability and number. Moreover, we found that the GPNMB alternative splicing type was the Alternative 3′ splice site, with the alternative splicing site in 143382985:143404102. Herein, GPNMB promotes a crucial regulatory mechanism with alternative splicing for neuronal survival after NHIE.

Objective: A method based on the high resolution mass spectrometry library and diagnostic ratio of characteristic components was established to identify the illegally added psoraleae fructus in wine and tea. Methods: High resolution mass spectrometry library of psoraleae fructus was constructed by high performance liquid chromatography quadrupole time of flight mass spectrometry （HPLC-TOF-MS） for preliminary screening. Combined with the diagnostic ratio method of the characteristic components by, high performance liquid chromatography, psoraleae fructus in different 20 samples of mixed wine and mixed tea from different picking time and origin was tested and analyzed The diagnostic ratio of characteristic component peak area, which was less affected by the origin, picking time and processing technology, has no significant difference between different matrix groups, and was selected as the identification index. Results: High resolution mass spectrometry library of psoraleae fructus was established by high performance liquid chromatography quadrupole time of flight mass spectrometry （HPLC-TOF-MS） for preliminary screening. Corylia/psoralen and psoralen/isopsoralen were selected as the two characteristic groups. The box diagram was drawn to determine that the non-abnormal value range of Corylia/Psoralen was 0.061~0.115, and the non-abnormal value range of Psoralen/Isopsoralen was 1.14~1.68. The established screening and confirmatory methods were validated by commercial samples. Conclusion: The method is simple and efficient, which provides technical support for cracking down on illegal addition of psoraleae fructus in wine and tea.