As an indigenous breed, the Tibetan chicken is found in highland regions and shows physiological adaptations to high altitude; however, the genetic changes that determine these adaptations remain ...elusive. We assumed that the microevolution of the Tibetan chicken occurred from lowland to highland regions with a continuous elevation range. In this study, we analyzed the genome of 188 chickens from lowland areas to the high‐altitude regions of the Tibetan plateau with four altitudinal levels. Phylogenetic analysis revealed that Tibetan chickens are significantly different from other altitude chicken populations. Reconstruction of the demographic history showed that the migration and admixture events of the Tibetan chicken occurred at different times. The genome of the Tibetan chicken was also used to analyze positive selection pressure that is associated with high‐altitude adaptation, revealing the well‐known candidate gene that participates in oxygen binding (HBAD), as well as other novel potential genes (e.g., HRG and ANK2) that are related to blood coagulation and cardiovascular efficiency. Our study provides novel insights regarding the evolutionary history and microevolution mechanisms of the high‐altitude adaptation in the Tibetan chicken.
Scaling up to a large number of qubits with high-precision control is essential in the demonstrations of quantum computational advantage to exponentially outpace the classical hardware and ...algorithmic improvements. Here, we develop a two-dimensional programmable superconducting quantum processor, Zuchongzhi, which is composed of 66 functional qubits in a tunable coupling architecture. To characterize the performance of the whole system, we perform random quantum circuits sampling for benchmarking, up to a system size of 56 qubits and 20 cycles. The computational cost of the classical simulation of this task is estimated to be 2–3 orders of magnitude higher than the previous work on 53-qubit Sycamore processor Nature 574, 505 (2019). We estimate that the sampling task finished by Zuchongzhi in about 1.2 h will take the most powerful supercomputer at least 8 yr. Our work establishes an unambiguous quantum computational advantage that is infeasible for classical computation in a reasonable amount of time. The high-precision and programmable quantum computing platform opens a new door to explore novel many-body phenomena and implement complex quantum algorithms.
Fluorescent nanodiamond (FND) is attracting much attention as a bioimaging agent because of its inherent biocompatibility and superior optical properties (e.g., excellent photostability and far‐red ...emission). However, for practical use in life science research, some issues such as higher brightness and ease of bioconjugation have to be solved. Here, it is shown that the 100‐nm FND particles fabricated by using nitrogen‐rich type Ib diamonds and high‐energy proton irradiation are highly fluorescent and readily functionalizable with proteins for biological applications. In the first approach, acid‐treated FND is noncovalently coated with glycoproteins or neoglycoproteins (i.e., proteins chemically modified with multiple sugar residues) for targeting hepatocytes via carbohydrate receptors. In the second approach, FND is first PEGylated and then covalently conjugated with streptavidin, to which biotin‐labeled antibodies of interest are linked. High targeting specificity of the bioconjugated FND is demonstrated with the human hepatoma cell line, HepG2, and breast cancer cell lines, ASB145‐1R, MCF‐7, and MDA‐MB‐231 cells. These approaches should be widely applicable to a variety of situations for specific targeting and labeling of cells.
Strategies are developed to functionalize fluorescent nanodiamond (FND) with proteins of various types for biological applications. In the first approach, ligand‐based targeting, FND is noncovalently coated with (neo)glycoproteins to target hepatocytes via their carbohydrate‐specific receptors. In the second approach, antibody‐based targeting, FND is conjugated with antibodies for high specific targeting of antigens on human breast cancer cell surfaces. These two approaches are expected to be widely applicable for specific targeting and labeling of live cells.
Chiral POM-based materials are particularly attractive due to the combination of the advantage of POMs with the importance of chirality. In this review, we summarize the developments of chiral ...POM-based materials, including their synthetic strategies, the calculations on the origin of chirality and the relevant applications. Display omitted
► We review the synthesis strategies and recent results of chiral polyoxometalates (POMs). ► Theoretical calculations on the origin of chirality within chiral POMs were discussed. ► The applications of chiral POMs in asymmetric catalysis, molecular recognition and NLO materials were summarized. ► The challenges of preparation and applications of chiral POMs were discussed.
Owing to the potential applications in catalysis, analytical chemistry, ion exchange, magnetism, biological chemistry and medicine, tremendous effort has been dedicated to exploring polyoxometalate (POM) chemistry. Chiral POM-based materials are particularly attractive due to the combination of the advantage of POMs with the importance of chirality. Nearly 100 chiral POM-based compounds were reported, which were mainly used as asymmetric catalysts, molecular recognition and nonlinear optical materials. In addition, the chirality within POM systems has attracted the attention of theoretical chemists and research was carried out to explore the origin of chirality by density functional theoretical methods. In this review, we summarize the developments of chiral POM-based materials, including their synthetic strategies, calculations on the origin of chirality and the relevant applications.
The cleavage of inert C–C bonds is a central challenge in modern chemistry. Multinuclear transition metal complexes would be a desirable alternative because of the synergetic effect of multiple metal ...centers. In this work, carbon–carbon bond cleavage and rearrangement of benzene by a trinuclear titanium hydride were investigated using density functional theory. The reaction occurs via a novel “two-state reactivity” mechanism. The important elementary steps consist of hydride transfer, benzene coordination, dehydrogenation, oxidative addition, hydride–proton exchange, and reductive elimination. Most importantly, the ground-state potential energy surface switches from nearly degenerate triplet and antiferromagnetic singlet states to a closed-shell singlet state in the dearomatization of benzene, which effectively decreases the activation barrier. Furthermore, the roles of the transition metal centers and hydrides were clarified.
This study evaluated the effects of pretransplantation minimal residual disease (pre‐MRD) on outcomes of patients with acute lymphoblastic leukemia (ALL) who underwent unmanipulated haploidentical ...stem cell transplantation (haplo‐SCT). A retrospective study including 543 patients with ALL was performed. MRD was determined using multiparametric flow cytometry. Both in the entire cohort of patients and in subgroup cases with T‐ALL or B‐ALL, patients with positive pre‐MRD had a higher incidence of relapse (CIR) than those with negative pre‐MRD in MSDT settings (P < 0.01 for all). Landmark analysis at 6 months showed that MRD positivity was significantly and independently associated with inferior rates of relapse (HR, 1.908; P = 0.007), leukemia‐free survival (LFS) (HR, 1.559; P = 0.038), and OS (HR, 1.545; P = 0.049). The levels of pre‐MRD according to a logarithmic scale were also associated with leukemia relapse, LFS, and OS, except that cases with MRD <0.01% experienced comparable CIR and LFS to those with negative pre‐MRD. A risk score for CIR was developed using the variables pre‐MRD, disease status, and immunophenotype of ALL. The CIR was 14%, 26%, and 59% for subjects with scores of 0, 1, and 2‐3, respectively (P < 0.001). Three‐year LFS was 75%, 64%, and 42%, respectively (P < 0.001). Multivariate analysis confirmed the association of the risk score with CIR and LFS. The results indicate that positive pre‐MRD, except for low level one (MRD < 0.01%), is associated with poor outcomes in patients with ALL who underwent unmanipulated haplo‐SCT.
Summary
Natural killer (NK) cells exert anti‐viral effects after haematopoietic stem cell transplantation (HSCT). The balance between inhibition and activation of NK cells determined by the inherited ...repertoire of killer cell immunoglobulin‐like receptors (KIR) genes may influence Epstein–Barr virus (EBV) reactivation after transplantation. To evaluate the relative contributions of KIR genotypes to EBV reactivation, we prospectively enrolled 300 patients with malignant haematological disease who were suitable for haploidentical HSCT. Univariate analysis showed that donors with KIR2DS1, KIR2DS3 or KIR3DS1 genes were associated with an increased risk of EBV reactivation hazard ratio (HR) 1·86, 95% confidence interval (CI) 1·19–2·9, P = 0·0067; HR 1·78, 95% CI 1·07‐2·97, P = 0·027; HR 1·86, 95% CI 1·19‐2·91, P = 0·0065 respectively. Multivariate analysis revealed that the presence of KIR2DS1, KIR2DS3 or KIR3DS1 genes was associated with increased EBV reactivation after HSCT. This effect was more evident in the absence of the cognate ligands for the corresponding activating receptors. Our present data firstly showed that donors with activating KIR genes, specifically activating KIR2DS1, KIR2DS3 and KIR3DS1, had an increased risk of EBV reactivation. Precaution for patients whose donors carry activating genes will help prevent EBV reactivation and improve patient prognosis after HSCT.
Treating neuropathic pain is a major clinical challenge, and the underlying mechanisms of neuropathic pain remain elusive. We hypothesized that neuropathic pain-inducing nerve injury may elicit ...neuronal alterations that recapitulate events that occur during development. Here, we report that WNT signaling, which is important in developmental processes of the nervous system, plays a critical role in neuropathic pain after sciatic nerve injury and bone cancer in rodents. Nerve injury and bone cancer caused a rapid-onset and long-lasting expression of WNTs, as well as activation of WNT/frizzled/β-catenin signaling in the primary sensory neurons, the spinal dorsal horn neurons, and astrocytes. Spinal blockade of WNT signaling pathways inhibited the production and persistence of neuropathic pain and the accompanying neurochemical alterations without affecting normal pain sensitivity and locomotor activity. WNT signaling activation stimulated production of the proinflammatory cytokines IL-18 and TNF-α and regulated the NR2B glutamate receptor and Ca2+-dependent signals through the β-catenin pathway in the spinal cord. These findings indicate a critical mechanism underlying the pathogenesis of neuropathic pain and suggest that targeting the WNT signaling pathway may be an effective approach for treating neuropathic pain, including bone cancer pain.
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To ensure a long-term quantum computational advantage, the quantum hardware should be upgraded to withstand the competition of continuously improved classical algorithms and ...hardwares. Here, we demonstrate a superconducting quantum computing systems Zuchongzhi 2.1, which has 66 qubits in a two-dimensional array in a tunable coupler architecture. The readout fidelity of Zuchongzhi 2.1 is considerably improved to an average of 97.74%. The more powerful quantum processor enables us to achieve larger-scale random quantum circuit sampling, with a system scale of up to 60 qubits and 24 cycles, and fidelity of FXEB=(3.66±0.345)×10-4. The achieved sampling task is about 6 orders of magnitude more difficult than that of Sycamore Nature 574, 505 (2019) in the classic simulation, and 3 orders of magnitude more difficult than the sampling task on Zuchongzhi 2.0 arXiv:2106.14734 (2021). The time consumption of classically simulating random circuit sampling experiment using state-of-the-art classical algorithm and supercomputer is extended to tens of thousands of years (about 4.8×104 years), while Zuchongzhi 2.1 only takes about 4.2 h, thereby significantly enhancing the quantum computational advantage.
Small studies suggest an association of donor-specific anti-human leukocyte antigen (HLA) antibodies (DSAs) with primary graft failure (GF) following haploidentical stem cell transplantation, but ...primary graft rejection (GR) was not discriminated from primary poor graft function (PGF). In this study, we aimed to determine the association of DSAs with primary GF, including GR and PGF, in patients who underwent unmanipulated haploidentical blood and marrow transplantation.
A total of 345 subjects were prospectively recruited and randomly selected as training group (n = 173) and validation group (n = 172). Patient plasma/serum was screened. For HLA antibody positive samples with a median fluorescent intensity (MFI) >500, DSAs were further tested using a LABScreen Single Antigen Kit (One Lambda).
A total of 342 patients (99.1%) achieved sustained myeloid engraftment. The median times to neutrophil engraftment and platelet engraftment were 13 days (range, 8-28 days) and 18 days (range, 6-330 days), respectively. The cumulative incidence of primary GF was 6.4 ± 1.3% and included GR (0.9 ± 0.5%) and PGF (5.5 ± .2%). Of the 345 cases tested, 39 (11.3%) were DSA positive. Multivariate models showed that DSAs (MFI ≥ 10,000) were correlated to primary GR (P < 0.001) and that DSAs (MFI ≥ 2000) were strongly associated with primary PGF (P = 0.005). All patients were classified into three groups for analysis. Group A included cases that were DSA negative and those with a DSA MFI <2000 (n = 316), group B included cases with a 2000 ≤ MFI < 10,000 (n = 19), and group C included cases with a MFI ≥ 10,000 (n = 10). The DSAs were associated with an increased incidence of the primary GF (3.2 vs. 31.6 vs. 60%, for groups A, B, and C, respectively, P < 0.001), transplant-related mortality (TRM) rate (17.2 vs. 14.7 vs. 33.3%, for groups A, B, and C, respectively, P = 0.022), and inferior overall survival (OS, 77.3 vs. 85.3 vs. 44.4%, for groups A, B, and C, respectively, P = 0.015). The primary GF was independently associated with a higher incidence of TRM (P < 0.001), inferior disease-free survival (P < 0.001), and OS (P < 0.001).
The findings confirmed the effect of DSAs on primary GF, including GR and PGF, and survival. Our results suggest incorporating DSAs in the algorithm for haploidentical donor selection.
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