Magnetic sensitivity of cryptochrome 4 from a migratory songbird.

Night-migratory songbirds are remarkably proficient navigators1. Flying alone and often over great distances, they use various directional cues including, crucially, a light-dependent magnetic compass2,3. The mechanism of this compass has been suggested to rely on the quantum spin dynamics of photoinduced radical pairs in cryptochrome flavoproteins located in the retinas of the birds4-7. Here we show that the photochemistry of cryptochrome 4 (CRY4) from the night-migratory European robin (Erithacus rubecula) is magnetically sensitive in vitro, and more so than CRY4 from two non-migratory bird species, chicken (Gallus gallus) and pigeon (Columba livia). Site-specific mutations of ErCRY4 reveal the roles of four successive flavin-tryptophan radical pairs in generating magnetic field effects and in stabilizing potential signalling states in a way that could enable sensing and signalling functions to be independently optimized in night-migratory birds.

Scalable Ab Initio Electronic Structure Methods with Near Chemical Accuracy for Main Group Chemistry.

This study evaluates the precision of widely recognized quantum chemical methodologies, CCSD(T), DLPNO-CCSD(T), and localized ph-AFQMC, for determining the thermochemistry of main group elements. DLPNO-CCSD(T) and localized ph-AFQMC, which offer greater scalability compared to canonical CCSD(T), have emerged over the past decade as pivotal in producing precise benchmark chemical data. Our investigation includes closed-shell, neutral molecules, focusing on their heat of formation and atomization energy sourced from four specific small molecule data sets. First, we selected molecules from the G2 and G3 data sets, noted for their reliable experimental heat of formation data. Additionally, we incorporate molecules from the W4-11 and W4-17 sets, which provide high-level theoretical reference values for atomization energy at 0 K. Our findings reveal that both DLPNO-CCSD(T) and ph-AFQMC methods are capable of achieving a root-mean-square deviation of less than 1 kcal/mol across the combined data set, aligning with the threshold for chemical accuracy. Moreover, we make efforts to confine the maximum deviations within 2 kcal/mol, a degree of precision that significantly broadens the applicability of these methods in fields such as biology and materials science.

Voltage-Modulated van der Waals Interaction in Single-Molecule Junctions.

Understanding how molecular geometry affects the electronic properties of single-molecule junctions experimentally has been challenging. Typically, metal-molecule-metal junctions are measured using a break-junction method where electrode separation is mechanically evolving during measurement. Here, to probe the impact of the junction geometry on conductance, we apply a sinusoidal modulation to the molecular junction electrode position. Simultaneously, we probe the nonlinearity of the current-voltage characteristics of each junction through a modulation in the applied bias at a different frequency. In turn, we show that junctions formed with molecules that have different molecule-electrode interfaces exhibit statistically distinguishable Fourier-transformed conductances. In particular, we find a marked bias dependence for the modulation of junctions where transmission is mediated thorough the van der Waals (vdW) interaction. We attribute our findings to voltage-modulated vdW interactions at the single-molecule level.

Inhibition of ecdysone receptor (DcEcR) and ultraspiracle (DcUSP) expression in Diaphorina citri increased susceptibility to pesticides.

Diaphorina citri Kuwayama is of great concern because of its ability to transmit devastating citrus greening illness (Huanglongbing). One strategy for controlling HLB may involve limiting the spread of D. citri. Insecticides using dsRNA target genes may be a useful option to control D. citri. The ecdysone receptor (EcR) and ultraspiracle (USP) are crucial for the growth and reproduction of insects. This study identified the genes for D. citri ecdysone receptor (DcEcR) and ultraspiracle (DcUSP). According to the qPCR data, DcUSP peaked at the 5th-instar nymph stage, while DcEcR peaked at the adult stage. Females expressed DcEcR and DcUSP at much higher levels than males. RNAi was used to examine DcEcR and DcUSP function. The findings demonstrated that inhibition of DcEcR and DcUSP delayed nymph development and decreased survival and eclosion rates. dsEcR caused adults to develop deformed wings, and dsUSP caused nymphs to wither and die. Female adult ovaries developed slowly, and the females laid fewer eggs. Additionally, DcEcR and DcUSP were inhibited, increasing D. citri susceptibility to pesticides. These findings suggest that DcEcR and DcUSP are critical for D. citri development, growth, and reproduction and may serve as potential targets for D. citri management.

Increased Molecular Conductance in Oligo[n]phenylene Wires by Thermally Enhanced Dihedral Planarization.

Coherent tunneling electron transport through molecular wires has been theoretically established as a temperature-independent process. Although several experimental studies have shown counter examples, robust models to describe this temperature dependence have not been thoroughly developed. Here, we demonstrate that dynamic molecular structures lead to temperature-dependent conductance within coherent tunneling regime. Using a custom-built variable-temperature scanning tunneling microscopy break-junction instrument, we find that oligo[n]phenylenes exhibit clear temperature-dependent conductance. Our calculations reveal that thermally activated dihedral rotations allow these molecular wires to have a higher probability of being in a planar conformation. As the tunneling occurs primarily through π-orbitals, enhanced coplanarization substantially increases the time-averaged tunneling probability. These calculations are consistent with the observation that more rotational pivot points in longer molecular wires leads to larger temperature-dependence on conductance. These findings reveal that molecular conductance within coherent and off-resonant electron transport regimes can be controlled by manipulating dynamic molecular structure.

[Dosage and curative effect of blood coagulation factor VIII in the prevention and treatment of haemophilia A in children].

OBJECTIVE: To study the correlation between dosage and curative effect of blood coagulation factor VIII in the prevention and treatment of haemophilia A in children and to determine the suitable dose for prevention of hemophilia in developing countries. METHODS: For different body weights of child patient, every time we used the same dosage of blood coagulation factor VIII (250 U each time, 3 times a week) and observed and recorded the number of hemorrhages in child patients. Then we compared the number of hemorrhages with children without treatment to determine the curative effect. According to the different body weights, we calculated the dosage of VIII factor of blood coagulation per kilogram (hereinafter referred to as the dose), and used Spearman correlation coefficient to study the correlation between dose and curative effect. RESULTS: The number of hemorrhages in 58 child patients before the treatment was 4.36 ± 1.78, while after the treatment was 2.22 ± 1.04 (t=7.91, P<0.001). The Spearman correlation coefficient of child patients of 5-10 U/kg was -0.421 (P=0.005); the Spearman correlation coefficient of child patients of 10-15 U/kg was -0.331 (P=0.030); the Spearman correlation coefficient of child patients over 15 U/kg was -0.16 (P=0.325). CONCLUSION: Prevention and treatment can significantly reduce the times of hemorrhage in hemophilia patients.

Andrographolide inhibits Burkitt's lymphoma by binding JUN and CASP3 proteins.

BACKGROUND: Burkitt's lymphoma, one of the most common subtypes of pediatric malignant lymphoma, is notorious for its swift onset, aggressive proliferation, pronounced invasiveness, and marked malignancy. The therapeutic landscape for Burkitt's lymphoma currently falls short of providing universally effective and tolerable solutions. Andrographolide, a primary active component of Andrographis paniculata, is renowned for its properties of heat-clearing, detoxification, inflammation reduction, and pain relief. It is predominantly used in treating bacterial and viral infections of the upper respiratory tract, as well as dysentery. Various reports highlight the antitumor effects of andrographolide. Yet, its specific impact and the underlying mechanism of action on Burkitt's lymphoma remain an uncharted area of research. METHOD: We employed network pharmacology to pinpoint the targets of andrographolide's action on Burkitt's lymphoma and the associated pathways. We then evaluated the impact of andrographolide on Burkitt's lymphoma using both in vitro and in vivo patient-derived xenograft (PDX) models. Concurrently, we confirmed the molecular targets of andrographolide in Burkitt's lymphoma through immunofluorescence assays. RESULT: Utilizing network pharmacology, we identified 15 relevant targets, 60 interrelationships between these targets, and numerous associated signaling pathways for andrographolide's action on Burkitt's lymphoma. In vitro efficacy tests using High-throughput Drug Sensitivity Testing and in vivo PDX model evaluations revealed that andrographolide effectively curtailed the growth of Burkitt's lymphoma. Moreover, we observed a increased in the expression of JUN (c-Jun) and CASP3 (Caspase 3) proteins in Burkitt's lymphoma cells treated with andrographolide. CONCLUSION: Andrographolide inhibits the growth of Burkitt's lymphoma by inhibiting JUN and CASP3 proteins.

The novel prognostic analysis of AML based on ferroptosis and cuproptosis related genes.

BACKGROUND: Acute myeloid leukemia (AML) is a hematological malignancy. The aim of this research was to develop a ferroptosis and cuproptosis related novel prognostic signature associated with AML. METHODS: The ferroptosis and cuproptosis related genes correlated with the prognosis of AML were identified by univariate Cox analysis. The consistent cluster analysis was performed for 150 AML patients in TCGA dataset. The key module genes associated with GSVA score of ferroptosis and cuproptosis were identified by WGCNA. univariate Cox and LASSO regression analysis were adopted to build a ferroptosis and cuproptosis AML prognostic signature. Finally, the expression of five prognostic genes in clinical tissue samples were verified by RT-qPCR. RESULTS: A grand total of 27 FCRGs associated with AML prognosis were identified.Then, two AML sub-types with significantly different survival were obtained. We found 3 significantly differential expressed immune cells (naive CD4 cells, regulatory T cells and resting mast cells) between two risk sub-groups. Meanwhile, 'IL6 JAK STAT3 signaling' and 'P53 pathway' were enriched in low-risk group. A ferroptosis and cuproptosis related prognostic signature was build based on 8 prognostic genes. RT-qPCR results indicated that there was no significant difference in the expression of OLFML2A and CD109 between AML and normal samples. However, compared to the control group, LGALS1, SOCS1, and RHOC showed significantly lower expression in the AML group. CONCLUSION: The prognostic signature comprised of OLFML2A, LGALS1, ABCB11, SOCS1, RHOC, CD109, RD3L and PTPN13 based on ferroptosis and cuproptosis was established, which provided theoretical basis for the research of AML.

Preparation and performance of a stimuli-responsive drug delivery system: novel light-triggered temperature-sensitive drug-loaded microcapsules.

Stimuli-responsive/smart drug delivery systems (DDSs), particularly those that use temperature as a stimuli-response factor to activate drug release, are the subject of recent research. A phase change material (PCM) is a popular thermally responsive material that can be used as a drug carrier and only when the system temperature is above the phase change point is the drug released following the phase change material changing from solid to liquid. In this study, a novel NIR light-triggered temperature-sensitive drug delivery system is developed for controllable release of acyclovir (ACV). For this purpose, a mixture of a phase change material (T38) and an ACV compound is first emulsified with copper oxide nanoparticles (CuO NPs) as a Pickering stabilizer and a photothermal conversion material, and then encapsulated with SiO2 to form a photothermal stimuli-responsive delivery system. This system shows a uniform spherical shape with a well-distinct core-shell structure, and is further experimentally proven to be able to controllably release drugs with solid-liquid transition of the phase change carrier upon temperature change. These results indicate that cumulative release of ACV can reach 51.2% at 40 °C within 20 hours, which is much higher than 27.3% release achieved below the melting point of T38. In addition, CuO NPs with excellent photothermal conversion ability endow the system with precisely controllable drug delivery via NIR light stimulation, where the cumulative drug release can reach 83.6% after 7 cycles of light stimulation, allowing controlled release at a specific time or location.

Network pharmacology- and molecular docking-based investigation of the therapeutic potential and mechanism of daucosterol against multiple myeloma.

Background: Some studies have shown that daucosterol has potential anti-tumor activity, but its therapeutic effect on multiple myeloma (MM) has not been reported. This study aimed to evaluate the therapeutic effect daucosterol against MM and explore its possible mechanism through network pharmacology. Methods: We collected daucosterol and approved drugs for MM, and their potential target profiles were obtained. We used 2 major methods to collect the gene sets related to the physiological process of MM. Based on the protein-protein interaction (PPI) network in the STRING database, the correlation between the therapeutic targets of daucosterol and MM-related genes was calculated by using the random walk with restart (RWR) algorithm to systematically evaluate the therapeutic potential of daucosterol for MM. On this basis, through intersection analysis, the potential targets of daucosterol in treating MM were identified, and the signaling pathways were mined. Furthermore, the key targets were identified. Finally, the regulatory relationship between the predicted daucosterol and potential targets was verified by molecular docking method, and the interaction mode between daucosterol and key targets was analyzed. Results: A total of 13 approved drugs reported to treat MM were retrieved from the DrugBank database. A total of 35 potential targets of daucosterol were obtained, including 8 known targets and 27 newly predicted targets. In the PPI network, the target of daucosterol was significantly correlated with MM-related genes, indicating that it has therapeutic potential for MM. A total of 18 therapeutic targets for MM were obtained, which were significantly enriched in the FoxO signaling pathway, prostate cancer, the PI3K-Akt signaling pathway, insulin resistance, the AMPK signaling pathway, and pathways related to the regulation of TP53. The core targets were HSP90AA1, MDM2, GSK3B, AKT3, PRKAA1, and PRKAB1. Molecular docking suggested that daucosterol had potential direct regulatory effects on 13 of the 18 predicted targets. Conclusions: This study highlights the use of daucosterol as a promising therapeutic drug for MM treatment. These data provide new insights into the potential mechanism of daucosterol in the treatment of MM, which may provide references for subsequent research and even the clinical treatment.

Bond Polarizability as a Probe of Local Crystal Fields in Hybrid Lead-Halide Perovskites.

A rotating organic cation and a dynamically disordered soft inorganic cage are the hallmark features of organic-inorganic lead-halide perovskites. Understanding the interplay between these two subsystems is a challenging problem, but it is this coupling that is widely conjectured to be responsible for the unique behavior of photocarriers in these materials. In this work, we use the fact that the polarizability of the organic cation strongly depends on the ambient electrostatic environment to put the molecule forward as a sensitive probe of the local crystal fields inside the lattice cell. We measure the average polarizability of the C/N-H bond stretching mode by means of infrared spectroscopy, which allows us to deduce the character of the motion of the cation molecule, find the magnitude of the local crystal field, and place an estimate on the strength of the hydrogen bond between the hydrogen and halide atoms. Our results pave the way for understanding electric fields in lead-halide perovskites using infrared bond spectroscopy.

Nanoenabled Enhancement of Plant Tolerance to Heat and Drought Stress on Molecular Response.

Global warming has posed significant pressure on agricultural productivity. The resulting abiotic stresses from high temperatures and drought have become serious threats to plants and subsequent global food security. Applying nanomaterials in agriculture can balance the plant's oxidant level and can also regulate phytohormone levels and thus maintain normal plant growth under heat and drought stresses. Nanomaterials can activate and regulate specific stress-related genes, which in turn increase the activity of heat shock protein and aquaporin to enable plants' resistance against abiotic stresses. This review aims to provide a current understanding of nanotechnology-enhanced plant tolerance to heat and drought stress. Molecular mechanisms are explored to see how nanomaterials can alleviate abiotic stresses on plants. In comparison with organic molecules, nanomaterials offer the advantages of targeted transportation and slow release. These advantages help the nanomaterials in mitigating drought and heat stress in plants.

Reversed Conductance Decay of 1D Topological Insulators by Tight-Binding Analysis.

Reversed conductance decay describes increasing conductance of a molecular chain series with increasing chain length. Realizing reversed conductance decay is an important step toward making long and highly conducting molecular wires. Recent work has shown that one-dimensional topological insulators (1D TIs) can exhibit reversed conductance decay due to their nontrivial edge states. The Su-Schrieffer-Heeger (SSH) model for 1D TIs relates to the electronic structure of these isolated molecules but not their electron transport properties as single-molecule junctions. Herein, we use a tight-binding approach to demonstrate that polyacetylene and other diradicaloid 1D TIs show a reversed conductance decay at the short chain limit. We explain these conductance trends by analyzing the impact of the edge states in these 1D systems on the single-molecule junction transmission. Additionally, we discuss how the self-energy from the electrode-molecule coupling and the on-site energy of the edge sites can be tuned to create longer wires with reversed conductance decays.

Cryptochrome magnetoreception: four tryptophans could be better than three.

The biophysical mechanism of the magnetic compass sensor in migratory songbirds is thought to involve photo-induced radical pairs formed in cryptochrome (Cry) flavoproteins located in photoreceptor cells in the eyes. In Cry4a-the most likely of the six known avian Crys to have a magnetic sensing function-four radical pair states are formed sequentially by the stepwise transfer of an electron along a chain of four tryptophan residues to the photo-excited flavin. In purified Cry4a from the migratory European robin, the third of these flavin-tryptophan radical pairs is more magnetically sensitive than the fourth, consistent with the smaller separation of the radicals in the former. Here, we explore the idea that these two radical pair states of Cry4a could exist in rapid dynamic equilibrium such that the key magnetic and kinetic properties are weighted averages. Spin dynamics simulations suggest that the third radical pair is largely responsible for magnetic sensing while the fourth may be better placed to initiate magnetic signalling particularly if the terminal tryptophan radical can be reduced by a nearby tyrosine. Such an arrangement could have allowed independent optimization of the essential sensing and signalling functions of the protein. It might also rationalize why avian Cry4a has four tryptophans while Crys from plants have only three.

[Clinical Efficacy and Prognostic Factors of Newly Diagnosed Children[JP] with Burkitt Lymphoma Treated by High-Dose and Short-Course Modified LMB Regimen ± Rituximab].

OBJECTIVE: To investigate the clinical efficacy and prognostic factors of high-dose and short-course modified LMB regimen ± Rituximab in the treatment of newly diagnosed children with Burkitt lymphoma, soas to provide more reference for clinical diagnosis and treatment with follow-up. METHODS: 91 newly diagnosed children with Burkitt lymphoma treated in our hospital from January 2007 to August 2016 were chosen. High-dose and short-course modified LMB regimen were used to treat children at different risk levels- Rituximab were added in treatment of high-risk group. The clinical characteristics and efficacy of the treatment were analyzed, and the related prognostic factors were evaluated. RESULTS: The overall survival rate and event-free survival rate in 5-year with follow-up of 91 children were separately（89.27±2.69）%， （87.16±2.30）%; the event-free survival rate of patients in 5-year with follow-up in low-risk, moderate-risk and high-risk group were separately 100%，（94.51±2.97）%，（84.60±3.40）%. The event-free survival rate in 5-year with follow-up of high-risk group were significantly lower than that of moderate-risk group（P<0.05）. Univariate analysis showed that the combination of maxillofacial and central nervous system invasion, LDH >1000 U/L, proportion of bone marrow tumor cell >25%, organ involvement number >4, St. Jude stage for IV stage, early chemotherapy insensitivity and tumor lesion in mid-term evaluation were risk factor for poor prognosis in newly diagnosed children with Burkitt lymphoma（P<0.05）.Multivariate analysis showed that the combination of maxillofacial and central nervous system invasion, early chemotherapy insensitivity and tumor lesion in mid-term evaluation were the independent risk factor for poor prognosis of children with Burkitt lymphoma（P<0.05）. The EFS rate in 5-year with follow-up of high-risk children treated with chemotherapy+rituximab was significantly higher than that of chemotherapy alone（P<0.05）. CONCLUSION: High-dose and short-course modified LMB regimen in the treatment of newly diagnosed children with Burkitt lymphoma shows satisfactory clinical efficacy. The children with central nervous system involvement, early chemotherapy insensitivity and tumor lesion in mid-term evaluation show the worse prognosis, while Rituximab added is more helpful to improve the long-term prognosis for high-risk children with Burkitt lymphoma.

[Change of Autophagic Activity of U266 Cells after Bortezomib -Resistance and Its Mechanisms].

OBJECTIVE: To explore the changes of autophagic activity after resistance of U266 cells to bortezomib (Bor) and its mechanisms. METHODS: The proliferation inhibition rate, 50% inhibitory concentration (IC50), drug-resistance coefficient, drug-resistance reversed multiple by 3-methyladenine (3-MA) in U266 and U266/Bor cells treated with Bor were detected and calculated by using MTT method, then the proliferation inhibition curve was drawed. The Western blot was used to detect the expression of LC3-I, IC3-II, p-mTOR, Beclin-1, ATG5 and ATG7 proteins. RESULTS: The Bor showed the its proliferation inhibition effect on U266 cells and U266/Bor cells, IC50 of Bor on U266 and U266/Bor cells on 24 hours were 35.7 nmol/L and 526.5 nmol/L respectively; the drug-resistance coefficient was 14.7; the drug-resistance reversed multiple by 3-MA was 2.7. The expression of LC3-II, Beclin11, ATG5 and ATG7 in U266/Bor cells was higher than that in U266 cells; after the treatment with Bor for 24 h, the expression levels of LC3-II, Beclin-1, ATG5 and ATG7 in U266 cells all decreased, as compared with levels before treatment; while the expression levels of LC3-II, Beclin-1, ATG5 and ATG7 in U266/Bor cells were higher than those before treatment. There were no significant difference of p-mTOR expression among U266, U266+Bor, U266/Bor, U266/Bor+Bor cells. CONCLUSION: The increase of autophagy closely relates with resistance of U266 cells to bortezomib, moreover with up-regulation of Beclin-1, ATG5 and ATG7 expression.

[Reversal Effect of Pioglitazone on Multidrug Resistance in K562/ADR Cells and Its Mechanism].

OBJECTIVE: To explore the reversal effect of pioglitazone (PIO) on multidrug resistance in K562/ADR cells and its mechanism. METHODS: The proliferation inhibition rate, half inhibition concentration (IC50) and drug-resistance reversal multipe were detected and the curve of proliferation inhibition rate was drawn by MTT assay, the transcription of PPARγ, CYP2C8 and CYP2J2 genes was detected by RT-PCR; the expression of PPARγ, CYP2C8 and CYP2J2 proteins was detected by Western blot. RESULTS: The IC50 of PIO on K562 and K562/ADR cells for 60 h was 326.7 µmol/L and 349.1 µmol/L respectively. The reversal multiple of 30 µmol/L PIO on ADR-resistance of K562/ADR cells was 6.4. After treatment of K562/ADR cells with PIO, the transcription of CYP2C8 and CYP2J2 and the protein expression of CYP2C8 and CYP2J2 significantly decreased, the transcription of PPARγ gene and the expression of PPARγ protein were not changed. CONCLUSIONS: Pioglitazone can reverse the adriamycin-resistance in K562/ADR cells that is closely related to the decrease of protein expression of CYP2C8 and CYP2J2. Pioglitazone is an effective multidrug resistance reversal agent for tumors.

Platelet and peripheral white blood cell counts at diagnosis predict the response of adult immune thrombocytopenia to recombinant human interleukin-11: A retrospective, single-center, case-control study.

This study evaluated the effectiveness of recombinant human interleukin-11 (rhIL-11) in the treatment of immune thrombocytopenia (ITP) and determined whether clinical and laboratory findings predicted the treatment response.This retrospective, single-center, case-control study included 103 adult patients with ITP treated between July 2010 and April 2014 at Jiangxi Province People's Hospital. About 49 patients in the pred+IL group received prednisone (conventional dose) combined with an rhIL-11 regimen, and 54 patients in the pred alone group received prednisone (conventional dose) alone. Demographic data, initial and follow-up platelet counts, proportions of patients achieving platelet counts ≥30 × 10/L (response) and ≥100 × 10/L (complete response) at different time points, and adverse reactions were compared between groups.Complete response rates were similar between groups overall but higher in the pred+IL group than in the pred alone group for newly diagnosed patients and those with severe ITP (P < .05). Proportions of patients achieving response or complete response at different time points were similar between groups overall but higher in the pred+IL group than in the pred alone group for newly diagnosed patients and those with severe ITP (P < .05). Posttreatment platelet count correlated negatively with platelet count at diagnosis and white blood cell (WBC) count at diagnosis in patients with newly diagnosed ITP (r = -0.337, P = .073 and r = -0.367, P = .050, respectively) or ITP with bleeding-related episodes (r = -0.357, P = .020 and r = -0.434, P = .004, respectively). No immediate or postinfusion severe adverse reactions were observed.rhIL-11 increased CR and improved hemostasis in patients with newly diagnosed or severe ITP. Platelet and WBC counts at diagnosis can predict the response to rhIL-11.