Rational design of a two-dimensional high-temperature ferromagnet from HCP cobalt.

Cobalt has the highest Curie temperature (Tc) among the elemental ferromagnetic metals and has a hexagonal close-packed (HCP) structure at room temperature. In this study, HCP Co was thinned to the thickness of several (n) unit cells along the c-axis and then passivated by halogen atoms, thus being named Co2nX2 (X = F, Cl, Br and I). For Co2X2 and Co3X2, all of them are not only kinetically but also thermodynamically stable from the viewpoint of the phonon spectra and molecular dynamics. Similar to HCP Co, two-dimensional (2D) Co2F2, Co2Cl2 and Co3X2 (X = Cl, Br and I) are still ferromagnetic metals within the Stoner model but Co2X2 (X = Br and I) is a ferromagnetic half-metal with the coexistence of the metallic behavior for one spin and the insulating behavior for the other spin. Taking into account the spin-orbital coupling (SOC), the easy-magnetization axis is within the plane where the magnetization is isotropic, making it look like a 2D XY magnet. Applying a critical biaxial strain could lead to an easy-magnetization axis changing from the in-plane to the out-of-plane direction. Finally, we use classical Monte Carlo simulations to estimate the Curie temperature (Tc) which is as high as 957 and 510 K for Co2F2 and Co2Cl2, respectively, because of the strong direct exchange interaction. Different from being obtained by mechanical or liquid exfoliation from van der Waals layered structures, our study opens up new possibilities to search for novel 2D ferromagnets from the elemental ferromagnets and provides opportunities for realizing realistic ultra-thin spintronic devices.

Chromosome-level genome assembly of hadal snailfish reveals mechanisms of deep-sea adaptation in vertebrates.

As the deepest vertebrate in the ocean, the hadal snailfish (Pseudoliparis swirei), which lives at a depth of 6,000-8,000 m, is a representative case for studying adaptation to extreme environments. Despite some preliminary studies on this species in recent years, including their loss of pigmentation, visual and skeletal calcification genes, and the role of trimethylamine N-oxide in adaptation to high-hydrostatic pressure, it is still unknown how they evolved and why they are among the few vertebrate species that have successfully adapted to the deep-sea environment. Using genomic data from different trenches, we found that the hadal snailfish may have entered and fully adapted to such extreme environments only in the last few million years. Meanwhile, phylogenetic relationships show that they spread into different trenches in the Pacific Ocean within a million years. Comparative genomic analysis has also revealed that the genes associated with perception, circadian rhythms, and metabolism have been extensively modified in the hadal snailfish to adapt to its unique environment. More importantly, the tandem duplication of a gene encoding ferritin significantly increased their tolerance to reactive oxygen species, which may be one of the important factors in their adaptation to high-hydrostatic pressure.

Effects of Zishen Huoxue Prescription on OGD/R-induced mitophagy in hippocampal neurons / 中国药理学通报

Aim To explore the protective effect of Zishen Huoxue Prescription on OGD/R-induced primary hippocampal neuron damage in rats and the possible mechanism. Methods After the isolated primary hippocampal neurons were identified by immunofluorescence, OGD/R induced neuronal damage, and the changes of autophagic flux at different re-oxygenation time were observed by confocal laser scanning microscopy. After OGD/R-induced primary hippocampal neurons were intervened with serum containing Zishen Huoxue Prescription, cell viability was detected by CCK-8, cell apoptosis was detected by flow cytometry, autophagosomes were detected by transmission electron microscopy, and autophagy-related protein expressions were detected by Western blot. Results 10% Zishen Huoxue Prescription-containing serum could significantly improve cell viability and reduce the proportion of cell apoptosis, increase the number of autophagosomes in neurons, and up-regulate the expression of autophagy-related protein PINK1, Parkin, and pATG16L1. Conclusions Zishen Huoxue Prescription can effectively resist OGD/R-induced apoptosis of primary hippocampal neurons in rats, and its effect may be related to the regulation of PINK1-Parkin pathway to promote mitophagy.

Evaluation of the effect of direct anterior total hip arthroplasty in the treatment of hip osteoarthritis / 中华地方病学杂志

Objective:To evaluate the clinical effect of direct anterior total hip arthroplasty in the treatment of hip osteoarthritis.Methods:From December 2017 to December 2020, 82 patients with hip osteoarthritis who received total hip arthroplasty in the department of orthopedics, 541 General Hospital, including 41 patients with direct anterior total hip arthroplasty as the observation group, and 41 patients with lateral total hip arthroplasty as the control group. The general indicators of the two groups of patients during the perioperative period (time of ambulatory activity, hospitalization, amount of intraoperative bleeding, and operation time) and the clinical efficacy evaluation indicators [visual analogue score (VAS), Harris hip joint function score, Western Ontario and McMaster Universities Arthritis Index (WOMAC) score] were compared.Results:The time of ambulatory activity was (15.54 ± 2.67) and (19.32 ± 3.18) h, after operation, respectively, and the time of hospitalization was (6.87 ± 0.87) and (8.03 ± 1.04) d, respectively, in the observation group and the control group. The differences between the two groups were statistically significant ( t = 5.83, 5.48, P < 0.001); there was no statistically significant difference between the two groups in the amount of intraoperative bleeding and operation time ( t = 0.81, 0.13, P > 0.05). There were statistically significant differences between the observation group and the control group in VAS (3 d, 1 month, 6 month after operation), Harris hip joint function score (1, 6 month after operation) and WOMAC score (1, 6 month after operation, t = 7.50, 11.03, 10.70, 6.20, 7.34, 7.10, 8.34, P < 0.001). The Harris hip joint function score and WOMAC score of patients in the same group between 1, 6 month after operation and pre-operation were significantly different ( P < 0.05). Conclusion:Direct anterior total hip arthroplasty is effective in the treatment of hip osteoarthritis, and can significantly improve the function of the hip joint and relieve the pain of the hip joint compared with lateral total hip arthroplasty.

Molecular Mechanisms of the Convergent Adaptation of Bathypelagic and Abyssopelagic Fishes.

Harsh environments provide opportunities to study how different species adapt, at the molecular level, to similar environmental stressors. High hydrostatic pressure, low temperature, and absence of sunlight in the deep-sea environment are challenging conditions for gene expression, cell morphology and vision. Adaptation of fish to this environment appears independently in at least 22 orders of fish, but it remains uncertain whether these adaptations represent convergent evolution. In this study, we performed comparative genomic analysis of 80 fish species to determine genetic evidences for adaptations to the deep-sea environment. The 80 fishes were divided into six groups according to their order. Positive selection and convergent evolutionary analysis were performed and functional enrichment analysis of candidate genes was performed. Positively selected genes (pik3ca, pik3cg, vcl and sphk2) were identified to be associated with the cytoskeletal response to mechanical forces and gene expression. Consistent signs of molecular convergence genes (grk1, ednrb, and nox1) in dark vision, skin color, and bone rarefaction were revealed. Functional assays of Grk1 showed that the convergent sites improved dark vision in deep-sea fish. By identifying candidate genes and functional profiles potentially involved in cold, dark, and high-pressure responses, the results of this study further enrich the understanding of fish adaptations to deep-sea environments.

Sympatric or micro-allopatric speciation in a glacial lake? Genomic islands support neither.

Apparent cases of sympatric speciation may actually be due to micro-allopatric or micro-parapatric speciation. One way to distinguish between these models is to examine the existence and nature of genomic islands of divergence, wherein divergent DNA segments are interspersed with low-divergence segments. Such islands should be rare or absent under micro-allopatric speciation but common in cases of speciation with gene flow. Sympatric divergence of endemic fishes is known from isolated saline, crater, postglacial, and ancient lakes. Two morphologically distinct cyprinid fishes, Gymnocypris eckloni scoliostomus (GS) and G. eckloni eckloni (GE), in a small glacial lake on the Qinghai-Tibet Plateau, Lake Sunmcuo, match the biogeographic criteria of sympatric speciation. In this study, we examined genome-wide variation in 46 individuals from these two groups. The divergence time between the GS and GE lineages was estimated to be 20-60 Kya. We identified 54 large genomic islands (≥100 kb) of speciation, which accounted for 89.4% of the total length of all genomic islands. These islands harboured divergent genes related to olfactory receptors and olfaction signals that may play important roles in food selection and assortative mating in fishes. Although the genomic islands clearly indicated speciation with gene flow and rejected micro-allopatric speciation, they were too large to support the hypothesis of sympatric speciation. Theoretical and recent empirical studies suggested that continual gene flow in sympatry should give rise to many small genomic islands (as small as a few kilobases in size). Thus, the observed pattern is consistent with the extensive evidence on parapatric speciation, in which adjacent habitats facilitate divergent selection but also permit gene flow during speciation. We suggest that many, if not most, of the reported cases of sympatric speciation are likely to be micro-parapatric speciation.

Clinical effect of total hip arthroplasty via Watson-Jone approach in treatment of hip osteoarthritis caused by advanced Kashin-Beck disease / 中华地方病学杂志

Objective:To observe the clinical effect of total hip arthroplasty via Watson-Jone approach in treatment of hip osteoarthritis caused by advanced Kashin-Beck disease.Methods:Forty six patients with hip osteoarthritis caused by advanced Kashin-Beck disease who were admitted to Department of Orthopedics of 541 General Hospital from January 2018 to June 2019 were selected as observation subjects, of which 23 patients received the conventional posterolateral approach as the control group, and the other 23 patients received the Watson-Jone approach as the study group. The Harris scores of the hip joints, the degree of pain (visual analogue scale), and complication rate of postoperative follow-up were compared between the patients of two groups before and after operation at different time periods (3, 6, 12, 24 months).Results:The preoperative Harris scores of the study group and the control group were (36.28 ± 6.57) and (37.51 ± 6.29) points, respectively, and the difference was not statistically significant ( t = 0.65, P = 0.520); at 3, 6, 12 and 24 months after operation, the scores were (86.65 ± 5.26), (80.91 ± 5.39), (88.59 ± 5.08), (83.33 ± 5.26), (90.37 ± 4.55), (85.05 ± 4.61), (92.06 ± 4.37), and (88.72 ± 4.56) points, the differences were statistically significant ( P < 0.05). The preoperative hip pain scores of the study group and the control group were (8.08 ± 0.45) and (7.96 ± 0.49) points, respectively, and the difference was not statistically significant ( t = 0.87, P = 0.392) ; at 3, 6, 12 and 24 months after operation, the scores were (2.08 ± 0.51), (2.55 ± 0.55), (1.68 ± 0.46), (2.07 ± 0.41), (1.32 ± 0.38), (1.71 ± 0.41), (1.01 ± 0.22), and (1.18 ± 0.28) points, the differences were statistically significant ( P < 0.05). The complication rate of postoperative in the study group was 0 (0/23), which was significantly lower than that [17.39% (4/23)] of the control group (χ 2 = 4.38, P = 0.036). Conclusion:Watson-Jone approach is adopted in total hip arthroplasty for patients with hip osteoarthritis caused by advanced Kashin-Beck disease, which can significantly reduce the pain of the hip joint and improve the function of the hip joint, with fewer postoperative complications, and is conducive to postoperative rehabilitation.

Two new species of the family Megalyridae (Hymenoptera) from China.

Two new species of the small and rarely collected family Megalyridae are described from China: Carminator daliensis Chen & Liuhe, sp. nov. from Yunnan and Ettchellsia hainanensis Chen & Liuhe, sp. nov. from Hainan. A key to megalyrid species of China is provided. The biogeographical implication of the new taxa is discussed.

Genome of the butterfly hillstream loach provides insights into adaptations to torrential mountain stream life.

Butterfly hillstream loach (Beaufortia kweichowensis), a benthic fish in the torrential mountain streams, possesses a totally flat ventrum, flattened craniofacial and body skeletons, and enlarged paired fins covered by substantially small keratinous structures. However, little is known about the genetic basis of these specialized morphological adaptations. Here we present a 448.52-Mb genome assembly with contig N50 length of 5.53 Mb by integrating Illumina short-read sequencing, Nanopore long-read sequencing and HiC-based chromatin map. Demographic history reconstruction of the butterfly hillstream loach reveals that the population dynamics is correlated with the different stages of uplifting of the Tibetan Plateau. Comparative genomic analysis finds evidence of six keratin genes in butterfly hillstream loach evolving under positive selection. Within these genes, two keratin genes exhibit species-specific and divergent amino acid changes, suggesting a role in the formation of the unculi. Additionally, a series of positively selected genes, rapid evolving genes, specific variant genes and expanded gene families are found, including genes related to Hedgehog, Notch and BMP pathways, which may be involved in craniofacial development. These findings may have important implications for understanding the genetic basis of phenotypic adaptation to torrential mountain stream life.

FishDB: an integrated functional genomics database for fishes.

BACKGROUND: Hundreds of genomes and transcriptomes of fish species have been sequenced in recent years. However, fish scholarship currently lacks a comprehensive, integrated, and up-to-date collection of fish genomic data. RESULTS: Here we present FishDB, the first database for fish multi-level omics data, available online at http://fishdb.ihb.ac.cn . The database contains 233 fish genomes, 201 fish transcriptomes, 5841 fish mitochondrial genomes, 88 fish gene sets, 16,239 miRNAs of 65 fishes, 1,330,692 piRNAs and 4852 lncRNAs of Danio rerio, 59,040 Mb untranslated regions (UTR) of 230 fishes, and 31,918 Mb coding sequences (CDS) of 230 fishes. Among these, we newly generated a total of 11 fish genomes and 53 fish transcriptomes. CONCLUSIONS: This release contains over 410,721.67 Mb sequences and provides search functionality, a BLAST server, JBrowse, and PrimerServer modules.

Comparative mitochondrial genome analysis of Neodontobutis hainanensis and Perccottus glenii reveals conserved genome organization and phylogeny.

To investigate the molecular evolution of mitochondrial genomes among the family Odontobutidae, the complete mitochondrial genomes of Neodontobutis hainanensis and Perccottus glenii were sequenced and compared with seven odontobutids species. The genome organization, base composition, codon usage, and gene arrangement of N. hainanensis exhibited high similarity to P. glenii compared to those of other Odontobutidae species. Reconstructed phylogenetic analyses of Odontobutidae strongly supported that Neodontobutis and Perccottus formed a unifying group sister to Odontobutis. Our molecular dating time revealed that the two species diverged approximately 21.7 Ma during Miocene, later than that of Odontobutis. Selection analyses showed stronger selective constraints in mitochondrial genes for P. glenii. However, two positively selected sites in NADH4 and NADH6 genes were respectively detected in N. hainanensis and P. glenii, indicating that they might evolve different metabolic performance in response to the contrasting environments.

Feasibility of evaluating the left ventricular function in patients with cardiovascular diseases by fully automatic quantified three-dimensional transthoracic echocardiography / 中华心血管病杂志

Objective: To investigate the clinical value of left ventricular function assessment in patients with cardiovascular disease by fully automatic quantified three-dimensional transthoracic echocardiography. Methods: One hundred and ninety-seven patients with cardiac diseases were examined by three-dimensional transthoracic echocardiography from September 2017 to May 2019. Data from 61 patients with grade 1 echocardiographic image quality were used to determine the default boundary values of endocardial end-diastolic and end-systolic phases. Clinical features were analyzed based on electronic medical records. The accuracy and repeatability of this strategy was evaluated by comparing left ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) measured by automated quantitative three-dimensional echocardiography and those measured by conventional manual transthoracic echocardiography, the latter served as gold standard. Results: The levels of LVEDV, LVESV and LVEF measured by automatic three-dimensional echocardiography were positively correlated with values obtained by manual measurement（r=0.97，0.97, 0.98, 0.97, 0.97, 0.96；P<0.05). The levels of LVEDV and LVESV measured by full-automatic three-dimensional echocardiography were significantly higher than those obtained by manual three-dimensional echocardiography（all P<0.05）. The classification and correlation of systolic dysfunction in patients with abnormal ventricular wall motion by automatic three-dimensional echocardiography were significantly improved after manual calibration (κ=0.74, P=0.00) as compared to without manual calibration (κ=0.63, P=0.00). The inter-observer and intra-observer variability of fully automated three-dimensional echocardiography were significantly smaller than manual three-dimensional echocardiography（both P<0.05）. Conclusion: Fully automatic quantified three-dimensional transthoracic echocardiography possesses excellent accuracy and repeatability in measuring left ventricular volume and function， and it is feasible for clinical application.

The design and the performance of an ultrahigh vacuum 3He fridge-based scanning tunneling microscope with a double deck sample stage for in-situ tip treatment.

Scanning tunneling microscope (STM) is a powerful tool for studying the structural and electronic properties of materials at the atomic scale. The combination of low temperature and high magnetic field for STM and related spectroscopy techniques allows us to investigate the novel physical properties of materials at these extreme conditions with high energy resolution. Here, we present the construction and the performance of an ultrahigh vacuum 3He fridge-based STM system with a 7 Tesla superconducting magnet. It features a double deck sample stage on the STM head so we can clean the tip by field emission or prepare a spin-polarized tip in situ without removing the sample from the STM. It is also capable of in situ sample and tip exchange and preparation. The energy resolution of scanning tunneling spectroscopy at T = 310 mK is determined to be 400 mK by measuring the superconducting gap with a niobium tip on a gold surface. We demonstrate the performance of this STM system by imaging the bicollinear magnetic order of Fe1+xTe at T = 5 K.

Correction to: Glycosylation of dentin matrix protein 1 is a novel key element for astrocyte maturation and BBB integrity

In the original publication, the label of Fig. 2C should be read as "GFAP/lectin/DAPI" not "DMP1/GFAP/lectin/DAPI".

Unbiased transcriptomic analyses reveal distinct effects of immune deficiency in CNS function with and without injury

The mammalian central nervous system (CNS) is considered an immune privileged system as it is separated from the periphery by the blood brain barrier (BBB). Yet, immune functions have been postulated to heavily influence the functional state of the CNS, especially after injury or during neurodegeneration. There is controversy regarding whether adaptive immune responses are beneficial or detrimental to CNS injury repair. In this study, we utilized immunocompromised SCID mice and subjected them to spinal cord injury (SCI). We analyzed motor function, electrophysiology, histochemistry, and performed unbiased RNA-sequencing. SCID mice displayed improved CNS functional recovery compared to WT mice after SCI. Weighted gene-coexpression network analysis (WGCNA) of spinal cord transcriptomes revealed that SCID mice had reduced expression of immune function-related genes and heightened expression of neural transmission-related genes after SCI, which was confirmed by immunohistochemical analysis and was consistent with better functional recovery. Transcriptomic analyses also indicated heightened expression of neurotransmission-related genes before injury in SCID mice, suggesting that a steady state of immune-deficiency potentially led to CNS hyper-connectivity. Consequently, SCID mice without injury demonstrated worse performance in Morris water maze test. Taken together, not only reduced inflammation after injury but also dampened steady-state immune function without injury heightened the neurotransmission program, resulting in better or worse behavioral outcomes respectively. This study revealed the intricate relationship between immune and nervous systems, raising the possibility for therapeutic manipulation of neural function via immune modulation.

[Relationship between HLA Gene Polymorphism and Aplastic Anemia in Northern Chinese Han Patients].

OBJECTIVE: To explore the relationship between HLA-A, -B, -C, -DRB1, -DQB1 gene polymorphism and aplastic anemia （AA）of 65 cases in Northern China. METHODS: The high resolution genotyping of HLA-A, -B, -C, -DRB1, -DQB1 alleles in 65 AA patients and 772 healthy controls was performed with polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO), the relationship between HLA-A, -B, -C, -DRB1, -DQB1 gene polymorphism and aplastic anemia was analyzed by Pearson Chi-square，Continuity Correction， Two-sided Fisher's Exact Test and Odds Ratio. RESULTS: The HLA-B*1302（10% vs 4.21%）, B*3501（7.69% vs 3.89%）, DRB1* 0701（10% vs 4.73%）, DRB1*0901（19.23% vs 7.58%）, DQB1*0202（9.23% vs 3.76%） gene frequency in AA patients was higher than those in health controls, the difference was statistically significant (P<0.05), the χ2 were 9.049, 4.336, 6.838, 20.974 and 8.968, OR ratio was 2.528, 2.061, 2.239, 2.904 and 2.605. However, the HLA-A*3303（1.54% vs 6.93%）, DQB1*0302（1.54% vs 6.02%） gene frequency in AA patients was lower than those in healthy controls, the difference was statistically significant (P<0.05), the χ2 was 5.726 and 4.505, the OR ratio were 0.210 and 0.244. CONCLUSION: The polymorphism of HLA-A, -B, -DRB1, -DQB1 alleles is associate with AA in these patient cases, the HLA-B*1302, HLA-B*3501, HLA-DRB1*0701, HLA-DRB1*0901 and HLA-DQB1*0202 may be sensitive genes to AA, while the HLA-A*3303 and HLA-DQB1*0302 may be protective genes on AA.

Common occurrence of Theileria annulata and the first report of T. ovis in dairy cattle from Southern Xinjiang, China.

Bovine theileriosis is a common tick-born disease infected by Theileria spp. causing loss of beef and dairy cattle worldwide, therefore, the aim of this study was to determine the prevalence and genetic diversity of Theileria spp. in Southern Xinjiang Uyghur Autonomous Region, China. We screened 493 dairy cattle blood samples from Southern Xinjiang to detect Theileria spp. by PCR. The overall prevalence of Theileria spp. was 23.5% (116/493). The most frequent Theileria sp. was Theileria annulata 22.5% (111/493), followed by T. orientalis (0.6%, 3/493) and T. ovis (0.2%, 1/493). Additionally, one sample was co-infected with T. annulata and T. orientalis. Phylogenetic analysis showed that the 11 T. annulata Tams1 sequences grouped into three sequence clusters that belonged to group 2 (Asia group) and shared 96.4% to 99.9% identity with to each other. Furthermore, our results revealed the presence of several T. orientalis MPSP genotypes (types 1, 2, and 5) in this region. In this study, T. annulata was found to be the most prevalent Theileria species in dairy cattle from Southern Xinjiang. Theileria ovis was detected in one DNA sample of a free-grazing dairy cow from China for the first time.

Chemokine Receptor CXCR3 in the Spinal Cord Contributes to Chronic Itch in Mice / 神经科学通报·英文版

Recent studies have shown that the chemokine receptor CXCR3 and its ligand CXCL10 in the dorsal root ganglion mediate itch in experimental allergic contact dermatitis (ACD). CXCR3 in the spinal cord also contributes to the maintenance of neuropathic pain. However, whether spinal CXCR3 is involved in acute or chronic itch remains unclear. Here, we report that Cxcr3 mice showed normal scratching in acute itch models but reduced scratching in chronic itch models of dry skin and ACD. In contrast, both formalin-induced acute pain and complete Freund's adjuvant-induced chronic inflammatory pain were reduced in Cxcr3 mice. In addition, the expression of CXCR3 and CXCL10 was increased in the spinal cord in the dry skin model induced by acetone and diethyl ether followed by water (AEW). Intrathecal injection of a CXCR3 antagonist alleviated AEW-induced itch. Furthermore, touch-elicited itch (alloknesis) after compound 48/80 or AEW treatment was suppressed in Cxcr3 mice. Finally, AEW-induced astrocyte activation was inhibited in Cxcr3 mice. Taken together, these data suggest that spinal CXCR3 mediates chronic itch and alloknesis, and targeting CXCR3 may provide effective treatment for chronic pruritus.