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Symbiotic interactions between legumes and rhizobia lead to the development of root nodules and nitrogen fixation by differentiated bacteroids within nodules. Differentiation of the endosymbionts is reversible or terminal, determined by plant effectors. In inverted repeat lacking clade legumes, nodule-specific cysteine-rich (NCR) peptides control the terminal differentiation of bacteroids. Medicago truncatula contains â¼700 NCR-coding genes. However, the role of few NCR peptides has been demonstrated. Here, we report characterization of fast neutron 2106 (FN2106), a symbiotic nitrogen fixation defective (fix-) mutant of M. truncatula. Using a transcript-based approach, together with linkage and complementation tests, we showed that loss-of-function of NCR343 results in impaired bacteroid differentiation and/or maintenance and premature nodule senescence of the FN2106 mutant. NCR343 was specifically expressed in nodules. Subcellular localization studies showed that the functional NCR343-YFP fusion protein colocalizes with bacteroids in symbiosomes in infected nodule cells. Transcriptomic analyses identified senescence-, but not defense-related genes, as being significantly upregulated in ncr343 (FN2106) nodules. Taken together, results from our phenotypic and transcriptomic analyses of a loss-of-function ncr343 mutant demonstrate an essential role of NCR343 in bacteroid differentiation and/or maintenance required for symbiotic nitrogen fixation.
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Medicago truncatula , Medicago truncatula/metabolismo , Fijación del Nitrógeno/genética , Cisteína/metabolismo , Péptidos/metabolismo , Simbiosis , Nódulos de las Raíces de las Plantas/metabolismoRESUMEN
Bistetrazoles are highly sought after for developing innovative high-energy density materials. The 1,1'-substituted bistetrazoles, exemplified by TKX-50, have outstanding performance. However, the research of high-perfomance 2,2'-substituted bistetrazoles remains limited. In this work, dinitromethyl groups were introduced into bistetrazole structures as 2,2'-substituted bistetrazoles (BDBTZ), which was extensively characterized through NMR, thermal analysis, and single crystal X-ray diffraction, exhibiting excellent oxygen balance, moderate sensitivity, acceptable thermal stability, high crystal density, and excellent detonation performance.
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Breast cancer is a hormone-dependence and heterogenic disease. Drug resistance is the main reason for the failure of breast cancer treatment. Combinatory medications are methods for treatment but they are not sufficient in action. However, new approaches like molecular therapy reveal a new insight into cancer treatment. Studies show that Bcl-2 gene family inhibitors and ER blockers cause the improvement of recovery. Interfering molecules such as antisense ones can inhibit the expression of Bcl-2 and push the cancer cells to apoptosis. Our team designed a new Antisense Oligonucleotide (ASO) based on Antisense oligo G3139. MCF-7 and MDA-MB-231 cell lines were used to evaluate cellular proliferation. Liposomes and cationic nano-complex (Niosome) are used to increase the cellular delivery of ASO and Tamoxifen. We also investigated the cytotoxicity and apoptotic effects of Tamoxifen, naked ASO and Nano-packed ASO. The results indicated significant down-regulation of the Bcl-2 gene and inhibition of MCF-7 and MDA-MB-231 cellular proliferation. Flow-cytometry showed early apoptosis in all cell groups. The newly designed ASO reduced the expression of the Bcl-2 gene. It also had a synergistic effect with the Tamoxifen. The cationic nano-complex (Niosome) was more efficient than the liposome in delivering designed oligo antisense Bcl-2 in the cancer cells.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/metabolismo , Liposomas/farmacología , Liposomas/uso terapéutico , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Apoptosis/genética , Tamoxifeno/farmacología , Tamoxifeno/uso terapéutico , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Línea Celular , Línea Celular TumoralRESUMEN
Selective regulation of stability and density via isomerism is a promising strategy for developing energetic materials. In this work, we selectively introduced dinitromethyl groups at different positions of 4-nitro-1,2,3-triazole. The regional heterogeneity endows a high crystal density by virtue of the dense packing; on the other hand, it changes the charge distribution in the molecule, and reinforces the hydrogen bonding interactions, all of which stabilize the material. The resulting compounds exhibit excellent detonation properties and impact sensitivity that are comparable to those of HMX (Dv = 9250 m s-1 and IS = 10 J).
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OBJECTIVES: To examine the reliability and accuracy of Walker's model for estimating the sex of Han adults in western China by using cranium three-dimensional (3D) CT reconstruction, and to study the suitable cranial sex estimation model for Han people in western China. METHODS: A total of 576 cranial CT 3D reconstructed images from Hanzhong Hospital in Shaanxi Province from 2017 to 2021 were collected. These images were divided into the experimental group with 486 samples and the validation group with 90 samples. Walker's model was used by observer 1 to estimate the sex of experimental group samples. The logistic function applicable to Han people in western China was corrected by observer 1. The 90 samples in the validation group were scored and substituted into the modified logistic function to complete the back substitution test by observer 1, 2 and 3. RESULTS: The accuracy of sex estimation of Han adults in western China was 63.2%-77.2% by applying Walker's model. The accuracy of modified logistic function was 82.9%. The accuracy of sex estimation through back substitution test by 3 observers was 75.6%-91.1%, with a Kappa value of 0.689 (P<0.05) for inter-observer consistency and 0.874 (P<0.05) for intra-observer consistency. CONCLUSIONS: There are great differences in bone characteristics among people from different regions. The modified logistic function can achieve higher accuracy in Han adults in western China.
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Determinación del Sexo por el Esqueleto , Humanos , Adulto , Reproducibilidad de los Resultados , Determinación del Sexo por el Esqueleto/métodos , Antropología Forense , Cráneo/diagnóstico por imagen , Cráneo/anatomía & histología , Imagenología Tridimensional , China , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Hemodialysis (HD) is the most important renal replacement therapy for patients with end-stage kidney disease (ESKD). Systemic inflammation is a risk factor of mortality in HD patients. Neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) are new inflammatory markers. However, previous studies have inconsistent conclusions about the predictive value of NLR, MLR and PLR on mortality of HD patients. The aim of this study was to establish an inflammation scoring system by including NLR, MLR and PLR, and evaluate the association between the inflammation score and all-cause and cardiovascular mortality in HD patients. METHODS: In this single center retrospective cohort study, 213 incident HD patients from January 1, 2015 to December 31, 2020 were included. Baseline demographic and clinical data and laboratory measurements were collected. According to the optimal cut-off values, NLR, MLR and PLR were assigned 0 or 1 point, respectively. Then, the inflammation score was obtained by adding the NLR, MLR and PLR scores. All patients were followed until July 31, 2021. The associations of the inflammation score with all-cause and cardiovascular mortality were assessed by multivariable-adjusted Cox models. RESULTS: Of 213 patients, the mean (± SD) age was 56.8 ± 14.4 years, 66.2% were men, and 32.9% with diabetes. The primary cause of ESKD was mainly chronic glomerulonephritis (46.5%) and diabetic nephropathy (28.6%). The median inflammation score was 2 (interquartile range = 1-3). During a median 30 months (interquartile range = 17-50 months) follow-up period, 53 patients had died, of which 33 deaths were caused by cardiovascular disease. After adjusting for demographics, primary diseases and other confounders in multivariable model, the inflammation score = 3 was associated with a hazard ratio for all-cause mortality of 4.562 (95% confidence interval, 1.342-15.504, P = 0.015) and a hazard ratio for cardiovascular mortality of 4.027 (95% confidence interval, 0.882-18.384, P = 0.072). CONCLUSION: In conclusion, an inflammation scoring system was established by including NLR, MLR and PLR, and the higher inflammation score was independently associated with all-cause mortality in HD patients.
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Enfermedades Cardiovasculares , Neutrófilos , Humanos , Adulto , Persona de Mediana Edad , Anciano , Monocitos , Pronóstico , Estudios Retrospectivos , LinfocitosRESUMEN
Pyridine derivatives based on the addition of trinitromethyl functional groups were synthesized by the reaction of N2O4 with the corresponding pyridinecarboxaldoximes, then they were converted into dinitromethylide hydrazinium salts. These energetic compounds were fully characterized by IR and NMR spectroscopy, elemental analysis, differential scanning calorimetry (DSC), and X-ray crystallography. These pyridine derivatives have good densities, positive enthalpies of formation, and acceptable sensitivity values. Theoretical calculations carried out using Gaussian 03 and EXPLO5 programs demonstrated good to excellent detonation velocities and pressures. Each of these compounds is superior in performance to TNT, while 2,6-bis(trinitromethyl)pyridine (D = 8700 m·s-1, P = 33.2 GPa) shows comparable detonation performance to that of RDX, but its thermal stability is too low, making it inferior to RDX.
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Sustancias Explosivas/síntesis química , Piridinas/síntesis química , Rastreo Diferencial de Calorimetría/métodos , Simulación por Computador , Cristalografía por Rayos X/métodos , Hidrazinas/química , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Óxidos de Nitrógeno/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , TermodinámicaRESUMEN
In drowning cases, it is difficult to judge whether the deceased died from drowning or throwing into the water after killed or identificate the cause of death of the decomposed corps in forensic practices. The diatom test is still considered as the important assistant evidence in drowning cases. This paper reviews research progress on technologies in recent years of forensic diatom test, and the application value of the new developing approach in the field of forensic medicine.
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Diatomeas/aislamiento & purificación , Ahogamiento/diagnóstico , Autopsia/métodos , Causas de Muerte , Diatomeas/clasificación , Medicina Legal , HumanosRESUMEN
The crystal structure of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaiso-wurtzitane (CL-20) p-xylene solvate, and the solvent effects on the crystal faces of CL-20 were studied through a combined experimental and theoretical method. The properties were analyzed by thermogravimetry-differential scanning calorimetry (TG-DSC), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD).The growth morphology of CL-20p-xylene solvate crystal was predicted with a modified attachment energy model. The crystal structure of CL-20p-xylene solvate belonged to the Pbca space group with the unit cell parameters, a=8.0704(12) Å, b=13.4095(20) Å, c=33.0817(49) Å, and Z=4, which indicated that the p-xylene solvent molecules could enter the crystal lattice of CL-20 and thus the CL-20 p-xylene solvate is formed. According to the solvent-effected attachment energy calculations, (002) and (11-1) faces should not be visible at all, while the percentage area of the (011) face could be increased from 7.81% in vacuum to 12.51% in p-xylene solution. The predicted results from the modified attachment energy model agreed very well with the observed morphology of crystals grown from p-xylene solution.
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Compuestos Aza/química , Compuestos Heterocíclicos/química , Modelos Moleculares , Xilenos/química , Cristalografía por Rayos X , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Anaphylaxis is a rare but well-known cause of sudden unexpected death, although data from forensic autopsies in anaphylactic deaths are limited. Herein, a retrospective study of a series of allergic deaths from 2009 through 2019 in Shanghai, China, was conducted to investigate the demographic, medical, and forensic pathological characteristics of fatal anaphylaxis to improve medicolegal understanding on anaphylactic death. Sixty-two autopsy cases of anaphylactic death were registered in this study. Males dominated the cases (74.2%) against females (25.8%), with an average age of 38.8 years. Medications (98.4%), particularly antibiotics (72.6%), were the most frequent cause of anaphylaxis, and 44 cases (71.0%) occurred in clinics administered illegally by unlicensed clinicians. The anaphylactic symptoms began within a few minutes to less than 1 h in 53 cases, with dyspnea (56.5%) and sudden shock (46.8%) being the most common clinical signs. Thirty cases (48.4%) of anaphylaxis resulted in death within 1 h. Laryngeal edema and multiple tissue eosinophil infiltration (85.5%) were the most prevalent autopsy findings, followed by pulmonary edema and congestion (24.2%), which were considered to be non-specific but suggestive. The comorbidities were mainly cardiovascular disease (33.9%), pneumonia (8.1%) and asthma (8.1%). Serum IgE were measured in 11 of 62 cases, ranging from 43.3 to 591 IU/ml, severed as a helpful marker. Therefore, we suggested a thorough analysis of allergen exposure, clinical history and autopsy findings is required for the diagnosis of anaphylactic death currently.
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Background: To investigate the relationship between serum Lactate dehydrogenase (LDH) and refractory Mycoplasma pneumoniae pneumonia (RMPP) in juvenile individuals. Methods: Search Chinese databases and English databases. The retrieval time limit is from the establishment of the database to 2022-04-27. And screening and inclusion of relevant diagnostic test literature. The QUADAS-2 method was used to evaluate the quality of the included literature. The random effects model was used to combine sensitivity, specificity, likelihood ratio, diagnostic odds ratio, summary receiver operating characteristic curve, and area under summary receiver operating characteristic curve to evaluate the prediction value of LDH for RMPP. Subgroup analyses were used to explore sources of heterogeneity. Results: â A total of 29 literatures that met the criteria were included in the study, and the quality of the literature was medium and high, with a total of 702,2 patients. â¡ The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve of the studies were: 0.75 (95% CI = 0.73-0.76), 0.73 (95% CI = 0.72-0.74), 3.61 (95% CI = 2.86-4.56), 0.30 (95% CI = 0.23-0.39), 13.04 (95% CI = 8.24-20.63), and 0.85(95% CI = 0.82-0.88). ⢠The results of subgroup analysis showed that Compared with the subgroup with LDH threshold ≤400â IU/L, the AUC increased from 0.84 (95% CI = 0.80-0.87) to 0.89 (95% CI = 0.86-0.91). Conclusions: The serum LDH has good accuracy for the diagnosis of RMPP and can serve as a diagnostic marker for RMPP.
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Treatment of 1-amino-1,2,3-triazole with sodium dichloroisocyanurate led to isolation of 1,1'-azobis-1,2,3-triazole, which was well characterized. Its structure was determined by X-ray crystallographic analysis, and its thermal stability and photochromic properties were investigated.
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Triazoles/química , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular , Fotoquímica , Triazoles/síntesis químicaRESUMEN
We developed a straightforward, fast, and versatile technique to fabricate mineralized nanofibrous polymer scaffolds for bone regeneration in this work. Nanofibrous poly(l-lactic acid) scaffolds were fabricated using both electrospinning and phase separation techniques. An electrodeposition process was designed to deposit calcium phosphate on the nanofibrous scaffolds. Such scaffolds contain a high quality mineral coating on the fiber surface with tunable surface topography and chemical composition by varying the processing parameters, which can mimic the composition and structure of natural bone extracellular matrix and provide a more biocompatible interface for bone regeneration.
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A new family of C-trinitromethyl-substituted pyrazoles was designed and obtained in good yields by the reaction of N2O4 with the pyrazolecarbaldehyde oxime followed by further N-nitration and C-nitration. All of the new compounds were fully characterized by IR and NMR spectroscopy, elemental analysis and differential scanning calorimetry (DSC). Compounds 2 and 3 were further confirmed by X-ray crystallography. These pyrazole derivatives have good densities, positive enthalpies of formation and acceptable sensitivity values. Theoretical calculations carried out using Gaussian 03 and EXPLO5 program demonstrate good to excellent detonation velocities and pressures in the range of ADN and HMX. Compound 3 exhibiting a positive oxygen balance, high specific impulse and moderate thermal stability is a promising high energy density oxidizer.
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A reliable in situ self-generating template strategy has been developed for the synthesis of flowerlike carbon nanosheets by hydrothermal carbonization in the presence of both silica and zinc acetate using glucose as the carbon source. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), powder X-ray diffraction (XRD), Raman spectroscopy, nitrogen sorption isotherm measurement (BET) and element analysis revealed the morphology, crystal phase structure, porosity and chemical composition. The formation of the zinc silicate nanosheet template was due to the hydrolysis of amorphous silica and self-assembly under hydrothermal conditions. The resulting flowerlike carbon nanosheets proved to be an excellent palladium catalyst support.
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A new energetic salt, hydrazinium 5-nitro-3-dinitromethyl-2H-pyrazole, was synthesized using 1-nitro-3-trinitromethylpyrazole and hydrazine as raw materials and fully characterized by IR and NMR spectroscopy, elemental analysis, and X-ray crystallography. The isomerization of N-nitropyrazole in the reaction condition was first reported and the possible mechanism was explained by the density functional theory method. The salt has good density, high positive enthalpy of formation superior to those of the RDX and HMX, and good detonation properties comparable to those of RDX. By denitration and isomerization reactions, the salt gains a better thermal stability and lower sensitivity toward impact and friction compared with its parent compound. Based on an overall energetic evaluation, the salt has a promising future as an alternative explosive. The research also contributes to the synthesis and application of polynitro-substituted N-heterocyclic compounds as energetic materials.
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147 homicidal cases were studied through case status, scene investigation, and postmortem examination. Its characters were then concluded for reference of detection in homicidal scene.
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Autopsia , Medicina Legal , Homicidio/legislación & jurisprudencia , Heridas y Lesiones/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Preescolar , Femenino , Homicidio/estadística & datos numéricos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Intoxicación , Estudios Retrospectivos , Suicidio , Adulto JovenRESUMEN
A series of trinitromethyl/trinitroethyl substituted derivatives of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5,5,0, 0(3.11),0(5.9)] dodecane (CL-20) were designed and investigated by theoretical methods. Intramolecular interactions between the trinitromethyl/trinitroethyl and the cage were investigated. The effects of trinitromethyl/trinitroethyl groups on stability of the parent compound are discussed. The results reveal a mutual influence of bond length and dihedral angle between the trinitromethyl and the cage. Compared to CL-20, the sensitivity of derivatives is barely affected. Properties such as density, heat of formation and detonation performance of these novel compounds were also predicted. The introduction of the trinitromethyl group can significantly enhance the oxygen balance, density and detonation properties of the parent compound. The remarkable energy properties make these novel cage compounds competitive high energy density materials.
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A tissue-engineering scaffold resembling the structure of the natural extracellular matrix can often facilitate tissue regeneration. Nerve and tendon are oriented micro-scale tissue bundles. In this study, a method combining injection molding and thermally induced phase separation techniques is developed to create single- and multiple-channeled nanofibrous poly(L-lactic acid) scaffolds. The overall shape, the number and spatial arrangement of channels, the channel wall matrix architecture, the porosity and mechanical properties of the scaffolds are all tunable. The porous NF channel wall matrix provides an excellent microenvironment for protein adsorption and the attachment of PC12 neuronal cells and tendon fibroblast cells, showing potential for neural and tendon tissue regeneration.