Biotoxicity of Halide Perovskites in Mice.

Halide perovskites are crystalline semiconductors with exceptional optoelectronic properties, rapidly developing toward large-scale applications. Lead (II) (Pb2+ ) is the core element used to prepare halide perovskites. Pb2+ can displace key 2+ elements, including calcium, zinc and iron, that regulate vital physiological functions. Sn2+ can replace Pb2+ within the perovskite structure and, if accidentally dispersed in the environment, it readily oxidizes to Sn4+ , which is compatible with physiological functions and thus potentially safe. The 3+ salt bismuth (III) (Bi3+ ) is also potentially safe for the same reason and useful to prepare double perovskites. Here, this work studies the biotoxicity of Pb, Sn, and Bi perovskites in mice for the first time. This work analyses histopathology and growth of mice directly exposed to perovskites and investigate the development of their offspring generation. This study provides the screening of organs and key physiological functions targeted by perovskite exposure to design specific studies in mammalians.

Reduced electron relaxation time of perovskite films via g-C3N4 quantum dot doping for high-performance perovskite solar cells.

Perovskite film-quality is a crucial factor to improve the photovoltaic properties of perovskite solar cells, which is closely related to the morphology of crystallization grain size of the perovskite layer. However, defects and trap sites are inevitably generated on the surface and at the grain boundaries of the perovskite layer. Here, we report a convenient method for preparing dense and uniform perovskite films, employing g-C3N4 quantum dots doped into the perovskite layer by regulating proper proportions. This process produces perovskite films with dense microstructures and flat surfaces. As a result, the higher fill factor (0.78) and a power conversion efficiency of 20.02% are obtained by the defect passivation of g-C3N4QDs.

Pupil Diameter Changes after Anesthesia with Different Doses of Sufentanil under Ultrasound Monitoring.

Objective: This study aims to observe the changes in pupil diameter (PD) after anesthesia with different doses of sufentanil with the ultrasound method and observe whether pupil contraction is correlated with hemodynamic changes and bispectral index (BIS) values. Methods: A total of 124 patients between the ages of 18-65 with ASA I-II undergoing general anesthesia for surgery were enrolled in the study. According to the sufentanil dose initially injected, they were randomly divided into groups P, S1, S2, and S3, with 31 cases in each group. Group P was injected with normal saline. Group S1 was injected with 0.2 µg/kg of sufentanil. Group S2 was injected with 0.4 µg/kg of sufentanil. Group S3 was injected with 0.6 µg/kg of sufentanil. Following propofol administration and eye closure, the pupil diameter (PD) of the patients in the four groups was observed and measured by ultrasound after the loss of consciousness (T1) and within 3 min after the sufentanil injection at an interval of 30 s (30 s (T2), 1 min (T3), 1 min 30 s (T4), 2 min (T5), 2 min 30 s (T6), and 3 min (T7)). PD, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and BIS values at T1-T7 were recorded. Results: The ultrasonic method was used to observe that different doses of sufentanil could make the patients' pupils contract. During anesthesia induction, the changes in PD have a positive correlation with SBP, DBP, HR, and BIS values. Conclusion: Ultrasound can become a new noninvasive method to monitor pupil changes during general anesthesia, and ultrasonic observation of pupil changes has great potential for individualized analgesia management in the perioperative period.

Dispersal into the Qinghai-Tibet plateau: evidence from the genetic structure and demography of the alpine plant Triosteum pinnatifidum.

Triosteum pinnatifidum Maxim., an alpine plant, is traditionally used for several medicinal purposes. Here, both chloroplast DNA sequences and nuclear low copy sequence markers were used to investigate the genetic diversity and population structure of T. pinnatifidum. Materials were collected from thirteen localities in the northeast Qinghai-Tibet Plateau (QTP) and adjacent highlands and advanced analytical toolkits were used to access their origin and range shifts. The results revealed a higher level of population differentiation based on chloroplast DNA (cpDNA) concatenated sequences compared with the nuclear DNA sequences (F ST = 0.654 for cpDNA, F ST = 0.398 for AT103), indicating that pollen flow was still extensive in T. pinnatifidum. A decline in haplotype variation was observed from the plateau edge and adjoining highlands toward the platform of the QTP. The hypothesis "dispersal into the QTP," proposing that T. pinnatifidum experienced migration from the plateau edge and adjacent highlands to the platform, was supported. These results were in line with the hypothesis that multiple refugia exist on the plateau edge and adjacent highlands rather than on the plateau platform. Our unimodal mismatch distribution, star-like network supported a recent expansion in T. pinnatifidum.

Exosomal microRNA-19b targets FBXW7 to promote colorectal cancer stem cell stemness and induce resistance to radiotherapy.

Colorectal cancer (CRC) continues to be one of the most malignant cancers with a high mortality rate to date. Promoting the radio-responsiveness of CRC is of great importance for local control and prognosis. In this study, we examined the roles of exosomal microRNA-19b (miR-19b) in CRC radioresistance. The regulatory role of miR-19b in CRC stem cells and radiotherapy-resistant cells was determined using miRNA microarray analysis, and its prognostic value was probed using the TCGA database. It was found that miR-19b was overexpressed in CRC tissues, which indicated a poor prognosis. CRC-derived exosomes (EXOs) enhanced the radio-resistance and stemness properties of CRC cells via delivery of miR-19b in vitro and in vivo. FBXW7 was identified as a putative target of miR-19b. On the contrary, reintroduction of FBXW7 reversed the effects of miR-19b on radioresistance and stemness properties. Furthermore, the Wnt/ß-catenin pathway activity was elevated in CRC cells upon EXOs treatment, decreased after miR-19b downregulation, and increased again after FBXW7 downregulation. These results suggest that miR-19b inhibition could enhance the efficacy of radiotherapy while reducing the stemness properties, thus presenting a promising strategy for sensitizing CRC cells to radiotherapy.

The complete chloroplast genome of Triosteum himalayanum (Caprifoliaceae), a perennial alpine herb.

Triosteum himalayanum is a perennial herb which is distributed in the eastern Himalayas, Hengduan Mountains, and central China. The complete chloroplast genome of T. himalayanum is studied for the first time, which is 154,579 bp in length and is divided into four regions: two inverted repeat (IRA and IRB) regions of 23,370 bp, a small single copy (SSC) region of 18,682 bp and a large single copy (LSC) region of 89,157 bp. The plastid genome contains 133 genes, including 86 protein-coding genes, 39 tRNA genes, and 8 rRNA genes. The overall CG content in the chloroplast genome of T. himalayanum is 38.38%. The phylogenetic analysis on the complete plastome sequence of T. himalayanum will help to show the intergeneric diversity of Caprifoliaceae.

Westwards and northwards dispersal of Triosteum himalayanum (Caprifoliaceae) from the Hengduan Mountains region based on chloroplast DNA phylogeography.

The varying topography and environment that resulted from paleoorogeny and climate fluctuations of the Himalaya-Hengduan Mountains (HHM) areas had a considerable impact on the evolution of biota during the Quaternary. To understand the phylogeographic pattern and historical dynamics of Triosteum himalayanum (Caprifoliaceae), we sequenced three chloroplast DNA fragments (rbcL-accD, rps15-ycf1, and trnH-psbA) from 238 individuals representing 20 populations. Nineteen haplotypes (H1-H19) were identified based on 23 single-site mutations and eight indels. Most haplotypes were restricted to a single population or neighboring populations. Analysis of molecular variance revealed that variations among populations were much higher than that within populations for the overall gene pool, as well as for the East Himalayan group (EH group) and the North Hengduan group (NHM group), but not for the Hengduan Mountains group (HM group). Ecoregions representing relatively high genetic diversity or high frequencies of private haplotypes were discovered, suggesting that this alpine herbaceous plant underwent enhanced allopatric divergence in isolated and fragmented locations during the Quaternary glaciations. The current phylogeographic structure of T. himalayanum might be due to heterogeneous habitats and Quaternary climatic oscillations. Based on the phylogeographic structure of T. himalayanum populations, the phylogenetic relationship of identified haplotypes and palaeodistributional reconstruction, we postulated both westwards and northwards expansion from the HM group for this species. The westwards dispersal corridor could be long, narrow mountain areas and/or the Yarlung Zangbo Valley, while the northwards movement path could be south-north oriented mountains and low-elevation valleys.

Population Genetic Differentiation and Taxonomy of Three Closely Related Species of Saxifraga (Saxifragaceae) from Southern Tibet and the Hengduan Mountains.

The effects of rapid, recent uplift of the Hengduan Mountains on evolution and diversification of young floristic lineages still remain unclear. Here, we investigate diversification of three closely related Saxifraga species with a distribution restricted to the Hengduan Mountains (HM) and southern Tibet, and comment on their taxonomy based on molecular evidence. Three chloroplast DNA fragments (rbcL, trnL-F, trnS-G) and the nuclear ribosomal DNA internal transcribed spacer (ITS) were employed to study genetic structure across 104 individuals from 12 populations of Saxifraga umbellulata, S. pasumensis, and S. banmaensis. Chloroplast DNA (cpDNA) phylogenies revealed two well supported clades, corresponding to S. umbellulata and S. pasumensis plus S. banmaensis. Topology of the ITS phylogeny was largely congruent with that generated from cpDNA haplotypes, but with minor conflicts which might be caused by incomplete lineage sorting. Analyses of molecular variance of both cpDNA and ITS datasets revealed that most variation was held between S. pasumensis s.l. (with S. banmaensis) and S. umbellulata (92.31% for cpDNA; 69.78% for ITS), suggesting a high degree of genetic divergence between them. Molecular clock analysis based on ITS dataset suggested that the divergence between S. pasumensis s.l. and S. umbellulata can be dated to 8.50 Ma, probably a result of vicariant allopatric diversification associated with the uplift events of the HM. Vicariance associated with HM uplifts may also have been responsible for infraspecific differentiation in S. pasumensis. In contrast, infraspecific differentiation in S. umbellulata was most likely triggered by Quaternary glaciations. The much lower levels of gene diversity within populations of S. pasumensis compared with S. umbellulata could have resulted from both range contractions and human collection on account of its putative medicinal properties. Combining evidence from morphology, geographical distributions and molecular phylogenetic data, we recommend that S. banmaensis should be treated as a synonym of S. pasumensis which in turn, and based on the same sources of evidence, should be treated as a separate species rather than as a variety of S. umbellulata.

Gene Flow Results in High Genetic Similarity between Sibiraea (Rosaceae) Species in the Qinghai-Tibetan Plateau.

Studying closely related species and divergent populations provides insight into the process of speciation. Previous studies showed that the Sibiraea complex's evolutionary history on the Qinghai-Tibetan Plateau (QTP) was confusing and could not be distinguishable on the molecular level. In this study, the genetic structure and gene flow of Sibiraea laevigata and Sibiraea angustata on the QTP was examined across 45 populations using 8 microsatellite loci. Microsatellites revealed high genetic diversity in Sibiraea populations. Most of the variance was detected within populations (87.45%) rather than between species (4.39%). We found no significant correlations between genetic and geographical distances among populations. Bayesian cluster analysis grouped all individuals in the sympatric area of Sibiraea into one cluster and other individuals of S. angustata into another. Divergence history analysis based on the approximate Bayesian computation method indicated that the populations of S. angustata at the sympatric area derived from the admixture of the 2 species. The assignment test assigned all individuals to populations of their own species rather than its congeneric species. Consistently, intraspecies were detected rather than interspecies first-generation migrants. The bidirectional gene flow in long-term patterns between the 2 species was asymmetric, with more from S. angustata to S. laevigata. In conclusion, the Sibiraea complex was distinguishable on the molecular level using microsatellite loci. We found that the high genetic similarity of the complex resulted from huge bidirectional gene flow, especially on the sympatric area where population admixtures occurred. This study sheds light on speciation with gene flow in the QTP.