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In van der Waals heterostructures (vdWHs), the manipulation of interlayer stacking/coupling allows for the construction of customizable quantum systems exhibiting exotic physics. An illustrative example is the diverse range of states of matter achieved through varying the proximity coupling between two-dimensional (2D) quantum spin liquid (QSL) and superconductors within the TaS2 family. This study presents a demonstration of the intertwined physics of spontaneous rotational symmetry breaking, hidden magnetism, and Ising superconductivity (SC) in the three-fold rotationally symmetric, non-magnetic natural vdWHs 6R-TaS2. A distinctive phase emerges in 6R-TaS2 below a characteristic temperature (T*) of approximately 30 K, which is characterized by a remarkable set of features, including a giant extrinsic anomalous Hall effect (AHE), Kondo screening, magnetic field-tunable thermal hysteresis, and nematic magneto-resistance. At lower temperatures, a coexistence of nematicity and Kondo screening with Ising superconductivity is observed, providing compelling evidence of hidden magnetism within a superconductor. This research not only sheds light on unexpected emergent physics resulting from the coupling of itinerant electrons and localized/correlated electrons in natural vdWHs but also emphasizes the potential for tailoring exotic quantum states through the manipulation of interlayer interactions.
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BACKGROUND: Astragaloside IV is a main medicinal active ingredient in Astragalus membranaceus Bge. var. mongholicus (Bge.) Hsiao, which is also the key biomarker of A. membranaceus quality. Ethylene has been well-documented to involve in secondary metabolites biosynthesis in plants. Nevertheless, how ethylene regulates astragaloside IV biosynthesis in A. membranaceus is still unclear. Therefore, in the present study different dosages and time-dependent exogenous application of ethephon (Eth) were employed to analyze astragaloside IV accumulation and its biosynthesis genes expression level in hydroponically A. membranaceus. RESULTS: Exogenous 200 µmol·L- 1Eth supply is most significantly increased astragaloside IV contents in A. membranaceus when compared with non-Eth supply. After 12 h 200 µmol·L- 1 Eth treatment, the astragaloside IV contents reaching the highest content at 3 d Eth treatment(P ≤ 0.05). Moreover, After Eth treatment, all detected key genes involved in astragaloside IV synthesis were significant decrease at 3rd day(P ≤ 0.05). However, SE displayed a significant increase at the 3rd day under Eth treatment(P ≤ 0.05). Under Eth treatment, the expression level of FPS, HMGR, IDI, SS, and CYP93E3 exhibited significant negative correlations with astragaloside IV content, while expression level of SE displayed a significant positive correlation. CONCLUSIONS: These findings suggest that exogenous Eth treatment can influence the synthesis of astragaloside IV by regulating the expression of FPS, HMGR, IDI, SS, CYP93E3 and SE. This study provides a theoretical basis for utilizing molecular strategies to enhance the quality of A. membranaceus.
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Objective: Investigate the impact of combined computerized cognitive training and occupational therapy on individuals with mild cognitive impairment (MCI). Methods: We randomly assigned 118 MCI patients into two groups: a combined intervention group (n = 37) and a control group (n = 81), the latter receiving standard nursing care. The intervention group additionally underwent 12 weeks of computerized cognitive training and occupational therapy. Blind assessors evaluated cognitive performance, anxiety, depression, and daily living activities before the intervention, post-intervention, and at a 3-month follow-up. Results: Repeated-measures analysis of variance showed that the sMoCA scores, HAMA scores, and ADL scores of the experimental group at T2 (post-intervention) and T3 (3-month follow-up) were higher than those of the control group, and the difference was statistically significant (p < 0.001, p < 0.001, p = 0.026). Conclusion: Computerized cognitive training combined with occupational therapy can improve patients' cognitive status, enhance their compliance with continuing care, and maintain their anxiety and self-care ability at a stable level. Clinical trial registration: https://www.chictr.org.cn/index.html, identifier ChiCTR2200065014.
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Transition metal compounds with kagome structure have been found to exhibit a variety of exotic structural, electronic, and magnetic orders. These orders are competing with energies very close to each other, resulting in complex phase transitions. Some of the phases are easily observable, such as the charge density wave (CDW) and the superconducting phase, while others are more challenging to identify and characterize. Here we present magneto-transport evidence of a new phase below ~ 35 K in the kagome topological metal CsV3Sb5 (CVS) thin flakes between the CDW and the superconducting transition temperatures. This phase is characterized by six-fold rotational symmetry in the in-plane magnetoresistance (MR) and is connected to the orbital current order in CVS. Furthermore, the phase is characterized by a large in-plane negative magnetoresistance, which suggests the existence of a three-dimensional, magnetic field-tunable orbital current ordered phase. Our results highlight the potential of magneto-transport to reveal the interactions between exotic quantum states of matter and to uncover the symmetry of such hidden phases.
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MgMn3(OH)6Cl2 serves readily as the classical Heisenberg kagome antiferromagnet lattice spin frustration material, due to its similarity to herbertsmithite in composition and crystal structure. In this work, nanosheets of MgMn3(OH)6Cl2 are synthesized through a solid-phase reaction. Low-temperature magnetic measurements revealed two antiferromagnetic transitions, occurring at â¼8 and 55 K, respectively. Utilizing high-pressure synchrotron radiation X-ray diffraction techniques, the topological structural evolution of MgMn3(OH)6Cl2 under pressures up to 24.8 GPa was investigated. The sample undergoes a second-order structural phase transition from the rhombohedral phase to the monoclinic phase at pressures exceeding 7.8 GPa. Accompanying the disappearance of the Fano-like line shape in the high-pressure Raman spectra were the emergence of new Raman active modes and discontinuities in the variations of Raman shifts in the high-frequency region. The phase transition to a structure with lower symmetry was attributed to the pressure-induced enhancement of cooperative Jahn-Teller distortion, which is caused by the mutual substitution of Mn2+ ions from the kagome layer and Mg2+ ions from the triangular interlayer. High-pressure ultraviolet-visible absorption measurements support the structural evolution. This research provides a robust experimental approach and physical insights for further exploration of classical geometrical frustration materials with kagome lattice.
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Tin selenide (SnSe) holds great potential for abundant future applications, due to its exceptional properties and distinctive layered structure, which can be modified using a variety of techniques. One of the many tuning techniques is pressure manipulating using the diamond anvil cell (DAC), which is a very efficient in situ and reversible approach for modulating the structure and physical properties of SnSe. We briefly summarize the advantages and challenges of experimental study using DAC in this review, then introduce the recent progress and achievements of the pressure-induced structure and performance of SnSe, especially including the influence of pressure on its crystal structure and optical, electronic, and thermoelectric properties. The overall goal of the review is to better understand the mechanics underlying pressure-induced phase transitions and to offer suggestions for properly designing a structural pattern to achieve or enhanced novel properties.
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Herbertsmithite, Cu3Zn(OH)6Cl2, serves as one of the most promising candidates for quantum spin liquids with a perfect quantum kagome Heisenberg antiferromagnetic system. It can comprise an ideal model system for studying the compression response of the unique structure as well as exotic properties of kagome quantum spin liquid materials, which is of fundamental importance from both scientific and technological viewpoints. In this work, the structural evolution of herbertsmithite was investigated via in situ X-ray diffraction and Raman scattering techniques up to 30 GPa. The trigonal herbertsmithite structure transformed into a monoclinic clinoatacamite-like structure at 12.6 GPa. High pressure seems to act in a reverse way as Zn-doping for herbertsmithite, with the distortion degree of the system changing continuously. The occurrence of the displacive and reversible phase transition between the polymorphs is a consequence of the interplay between the external pressure and cooperative Jahn-Teller (JT) effect, aided by the presence of antisite mutual substitution of magnetic Cu2+ ions and nonmagnetic Zn2+ ions between the kagome layer and interlayer sites.
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BACKGROUND: Sepsis is a life-threatening disease with a limited effectiveness and the potential mechanism remains unclear. LncRNA NEAT-2 is reported to be involved in the regulation of cardiovascular disease. This study aimed to investigate the function of NEAT-2 in sepsis. METHODS: We built sepsis animal model with Male Balb/C mice induced by cecal ligation and puncture (CLP). A total of 54 mice were randomly assigned into eight groups: sham operation group (n = 18), CLP group (n = 18), CLP plus si-control group (n = 3), CLP plus si-NEAT2 group (n = 3), CLP plus mimic control group (n = 3), CLP plus miR-320 group (n = 3), CLP plus normal saline group (n = 3), and normal control group (n = 3). The number of peripheral endothelial progenitor cells (EPCs), the expression level of NEAT-2 and miR-320 were detected during progression of sepsis, as well as the number of peripheral EPCs and level of TNF-α, IL-6, VEGF, ALT, AST and Cr. In addition, the function of EPCs was evaluated after NEAT-2 knockdown and miR-320 overexpression in vitro. RESULTS: The number of circulating EPCs increased significantly in sepsis. NEAT-2 expression was significantly increased in the progress of sepsis, accompanied with miR-320 downregulated. NEAT-2 knockdown and miR-320 overexpression attenuated hepatorenal function and increased cytokines in sepsis. Moreover, NEAT-2 knockdown and miR-320 overexpression decreased the proliferation, migration and angiogenesis of endothelial progenitor cells in vitro. CONCLUSIONS: LncRNA-NEAT2 regulated the number and function of endothelial progenitor cells via miR-320 in sepsis, which may contribute to the development of novel potential clinical therapy for sepsis.
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Células Progenitoras Endoteliales , MicroARNs , ARN Largo no Codificante , Sepsis , Ratones , Masculino , Animales , ARN Largo no Codificante/genética , Hígado/metabolismo , Sepsis/genética , Sepsis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Modelos Animales de EnfermedadRESUMEN
Anisotropy is a manifestation of lowered symmetry in material systems that have profound fundamental and technological implications. For van der Waals magnets, the two-dimensional (2D) nature greatly enhances the effect of in-plane anisotropy. However, electrical manipulation of such anisotropy as well as demonstration of possible applications remains elusive. In particular, in-situ electrical modulation of anisotropy in spin transport, vital for spintronics applications, has yet to be achieved. Here, we realized giant electrically tunable anisotropy in the transport of second harmonic thermal magnons (SHM) in van der Waals anti-ferromagnetic insulator CrPS4 with the application of modest gate current. Theoretical modeling found that 2D anisotropic spin Seebeck effect is the key to the electrical tunability. Making use of such large and tunable anisotropy, we demonstrated multi-bit read-only memories (ROMs) where information is inscribed by the anisotropy of magnon transport in CrPS4. Our result unveils the potential of anisotropic van der Waals magnons for information storage and processing.
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Prevotella melanogenica is a typical organism present in the human oral cavity and female reproductive tract, which is responsible for causing periodontal disease and the inflammation of the female reproductive tract. The present report discusses the case of a young female patient who presented with cough and fever as the main clinical symptoms. Computed Tomography (CT) revealed multiple clusters of ground glass density shadows in both lungs, with network-like and paving stone-like changes. The alveolar lavage fluid was collected for next-generation sequencing, which revealed the presence of Prevotella melanogenica. The patient received treatments, CT revealed that the density of multiple flakes of ground glass density in both lungs was lower than the previously observed density. Prevotella melanogenica pneumonia is rare, and the paving stone symptom observed in CT is not specific. Therefore, the case reported here provides a novel perspective regarding the diagnosis of pneumonia.
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COVID-19 , Neumonía , Humanos , Femenino , Pulmón , Neumonía/complicaciones , COVID-19/complicaciones , Tos/etiología , Tomografía Computarizada por Rayos X/métodosRESUMEN
PURPOSE: Reports of mesh infections following open tension-free inguinal hernioplasty are gradually increasing. Recent research has focused on identifying and managing mesh infections. However, studies examining the long-term outcomes and quality of life following mesh removal for late-onset infections are few. This study aimed to analyze the short and long-term outcomes after maximal removal of the implanted mesh in patients with late-onset mesh infection after open tension-free inguinal hernioplasty. METHODS: Data of 105 patients who developed late-onset mesh infection after open tension-free inguinal hernioplasty and were admitted to our hospital from January 2014 to January 2019 were retrospectively analyzed. Patients were followed up by telephone or outpatient consultation for 3 years, focusing on hernia recurrence and mesh infection recurrence. Quality of life was assessed preoperatively and postoperatively using our developed scale; postoperative inguinal area pain was assessed using the visual analog score, and postoperative anxiety was assessed using the anxiety self-assessment scale. RESULTS: Of the 105 patients who experienced late-onset mesh infection following open inguinal hernioplasty, 100 underwent mesh plug repair. The mean follow-up time was 58 months, and 10.5% (95/105) of the patients were lost to follow-up. Recurrence of infection was observed in 28.6% of patients (2/7) who underwent partial mesh removal and in 3.4% of patients (3/88) who underwent complete mesh removal. One inguinal hernia recurred 12 months after mesh removal (1.0% recurrence rate). In the third year following surgery as compared to the preoperative period, there were significant improvements in quality of life. CONCLUSIONS: Hernia plugs may not be a good choice in tension-free inguinal hernia repair in view of the risk of late infections and fistulas. Remove all mesh at the time of the first operation for mesh infection. Hernia recurrence after late-onset infected mesh removal following open inguinal tension-free hernioplasty is rare. The post-operative quality of life, pain, and anxiety are gradually steadily improving.
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Hernia Inguinal , Humanos , Estudios de Seguimiento , Resultado del Tratamiento , Hernia Inguinal/cirugía , Hernia Inguinal/etiología , Herniorrafia/efectos adversos , Mallas Quirúrgicas/efectos adversos , Calidad de Vida , Estudios Retrospectivos , Dolor Postoperatorio/etiología , RecurrenciaRESUMEN
OBJECTIVES: Postoperative delirium is a common severe complication in patients in the intensive care unit after cardiac surgery. We developed a two-stage prediction model and quantified the risk of developing postoperative delirium to assist in early prevention before and after surgery. METHODS: We conducted a prospective cohort study and consecutively recruited adult patients after cardiac surgery. The Confusion Assessment Method for patients in the intensive care unit was used to diagnose delirium 5 days postoperatively. The stage I model was constructed using patient demographics, health conditions and laboratory results obtained preoperatively, whereas the stage II model was built on both pre- and postoperative predictors. The model was validated internally using the bootstrap method and externally using data from an external cohort. RESULTS: The two-stage model was developed with 654 patients and was externally validated with 214 patients undergoing cardiac surgery. The stage I model contained 6 predictors, whereas the stage II model included 10 predictors. The stage I model had an area under the receiver operating characteristic curve of 0.76 (95% confidence interval: 0.68-0.81), and the stage II model's area under the receiver operating characteristic curve increased to 0.85 [95% confidence interval (CI): 0.81-0.89]. The external validation resulted in an area under the curve of 0.76 (95% CI: 0.67-0.86) for the stage I model and 0.78 (95% CI: 0.69-0.86) for the stage II model. CONCLUSIONS: The two-stage model assisted medical staff in identifying patients at high risk for postoperative delirium before and 24 h after cardiac surgery. This model showed good discriminative power and predictive accuracy and can be easily accessed in clinical settings. TRIAL REGISTRATION: The study was registered with the US National Institutes of Health ClinicalTrials.gov (NCT03704324; registered 11 October 2018).
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Procedimientos Quirúrgicos Cardíacos , Delirio , Delirio del Despertar , Adulto , Humanos , Delirio del Despertar/complicaciones , Delirio/diagnóstico , Delirio/etiología , Delirio/prevención & control , Estudios Prospectivos , Unidades de Cuidados Intensivos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiologíaRESUMEN
In recent years, renewable and clean energy has become increasingly important due to energy shortage and environmental pollution. Selecting plants as the carbon precursors to replace costly non-renewable energy sources causing severe pollution is a good choice. In addition, owing to their diverse microstructure and the rich chemical composition, plant-based carbon materials are widely used in many fields. However, some of the plant-based carbon materials have the disadvantage of possessing a large percentage of macroporosity, limiting their functionality. In this paper, we first introduce two characteristics of plant-derived carbon materials: diverse microstructure and rich chemical composition. Then, we propose improvement measures to cope with a high proportion of macropores of plant-derived carbon materials. Emphatically, size regulation methods are summarized for micropores (KOH activation, foam activation, physical activation, freezing treatment, and fungal treatment) and mesopores (H3PO4 activation, enzymolysis, molten salt activation, and template method). Their advantages and disadvantages are also compared and analyzed. Finally, the paper makes suggestions on the pore structure improvement of plant-derived carbon materials.
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Clinoatacamite (γ-Cu2(OH)3Cl) possesses a geometrically frustrated kagome lattice for the S = 1/2 antiferromagnetic spin system. Thus, it is deemed as the mother compound of many promising quantum spin liquid materials. Here, we synthesized clinoatacamite consisting of homogeneous octahedron-like particles with an average size of 1-2 µm via a hydrothermal strategy. Clinoatacamite crystallizes in a monoclinic lattice composed of Jahn-Teller distorted Cu(OH)6 and Cu(OH)4Cl2 octahedrons. The bonding nature of clinoatacamite is characterized using Raman scattering and FTIR absorption spectroscopies, which reveal the existence of trimeric hydrogen bonds. The magnetic measurements indicate that at temperatures below about 6 K, the magnetic response of the prepared samples is dominated by weak ferromagnetic contributions. The compression behavior is investigated by in situ high-pressure synchrotron radiation X-ray diffraction and Raman scattering spectroscopy. An isostructural phase transition is observed at about 8.4 GPa, which is evidenced by the anomalies in the variation curves of the lattice parameters and Raman scattering frequencies with pressure. The occurrence of the isostructural phase transition is attributed to the competition and cooperation of the external pressure and intrinsic Jahn-Teller effect, together with the interplay of intrastructural hydrogen bonding.
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A new type of economical covalent organic framework material(COF), namely resin based covalent organic framework material, was prepared by combining resin and covalent organic framework material by hydrothermal synthesis, which was based on the preparation of traditional COF material(TpBD COF). The properties of the material and covalent organic framework material were compared in the way of characterization, and the possible reaction mechanism was analyzed. The solid phase extraction separation (SPE) ability of this material for four kinds of phenolic endocrine disrupting compounds (bisphenol F, bisphenol A, octylphenol and nonylphenol) in beverage samples was investigated. The results showed that the prepared COF materials had abundant internal channels, ordered structure, large specific surface area (TpBD COF: 814.6 m2/g and resin based COF: 623.9 m2/g) and good thermal stability (pyrolysis temperature was 443 °C and 437 °C, respectively). Solid phase extraction experiments demonstrated that the two COF materials as adsorbent of solid phase extraction column had ideal adsorption separation effect and good anti-interference ability, and had strong anti-interference ability. The SPE effect was superior to the traditional solid phase extraction column. The precision RSD of this method was less than 3%. This SPE method had high recovery and could be reused (carbonated beverage: 98.18-102.18% and beverage: 98.52-101.79%), In addition, the recovery of the material did not change significantly in the 50 cycles of solid phase extraction, indicating that the material had good stability and could be reused, which could meet the requirements for the detection and analysis of trace pollutants in environmental samples. The resin based COF material prepared in this study could reduce the cost of monomer uses and provide a possibility for its industrial production. At the same time, as an efficient SPE adsorbent, it also provided a new research scheme for the enrichment of trace phenolic endocrine disruptors in beverage samples.
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The crystal stacking order plays a crucial role in determining the structure and physical properties of 2D layered materials. A variation in the stacking sequence of adjacent 2D building blocks causes drastic changes in their functionalities. In this work, the structural variation of belloite (Cu(OH)Cl), as a function of pressure, is presented. Through in situ synchrotron X-ray diffraction and Raman scattering studies, in combination with first-principles theoretical simulations, a structural transformation from the initial monoclinic phase into an orthorhombic one has been established at 18.7 GPa, featuring variations in the stacking sequence of the tectonic monolayers. In the monoclinic phase, they are arranged in an AAAA sequence. While in the orthorhombic phase, the monolayers are stacked in an ABAB sequence. Such phenomena are similar to those observed in van der Waals 2D materials, with pressure-induced changes in the stacking order between layers. In addition, an isostructural phase transition within the initial monoclinic phase is also observed to occur at 12.9-16 GPa, which is associated with layer-sliding and a change in hydrogen bond configuration. These results show that Cu(OH)Cl, as well as other hydrogen-bonded 2D layered materials, can provide a convenient platform for studying the effects of the crystal stacking order.
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BACKGROUND: Analysis of the risk factors associated with functional delayed gastric emptying after distal gastric cancer surgery to provide a basis for further reduction of the incidence of this complication. METHODS: Total of 1382 patients with distal gastric cancer from January 2016 to October 2018 were enrolled. Correlation analysis was performed in 53 patients with FDGE by logistic regression. Subgroup risk analysis was performed in 114 patients with preoperative pyloric obstruction. A Pearson Chi-square analysis was used to compare categorical variables between normal distribution groups. Meanwhile, a t test was used to compare continuous variables between groups. Odds ratio (OR) was used for comparison of the two groups, and it was summarized with its 95% confidence interval (CI) and p value using logistic regression. RESULT: In multivariable analysis, age (OR 1.081, 95% CI, 1.047-1.117), BMI (OR 1.233, 95% CI, 1.116-1.363), preoperative pyloric obstruction (OR 3.831, 95% CI, 1.829-8.023), smaller volume of residual stomach (OR 1.838, 95% CI, 1.325-6.080), and anastomosis in greater curvature perpendicular (OR 3.385, 95% CI, 1.632-7.019) and in greater curvature parallel (OR 2.375, 95% CI, 0.963-5.861) were independent risk factors of FDGE. In the preoperative pyloric obstruction group, higher BMI (OR 1.309, 95% CI, 1.086-1.579) and preoperative obstruction time (OR 1.054, 95% CI, 1.003-1.108) were independent risk factors of FDGE and preoperative gastrointestinal decompression (OR 0.231, 95% CI, 0.068-0.785) was independent protective factor of FDGE. CONCLUSION: Adequate gastrointestinal decompression should be performed before the operation to reduce the incidence of postoperative gastroparesis in patients with preoperative pyloric obstruction. We also could improve the surgical methods to reduce the occurrence of FDGE, such as controlling the size of the residual stomach, ensuring blood supply. Especially selecting an appropriate stapler and anastomosis during the anastomosis process, the occurrence of FDGE can be reduced.
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Gastroparesia , Neoplasias Gástricas , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Gástricas/cirugíaRESUMEN
Noble metal nitrides (NMNs) have important theoretical significance and potential application prospects due to their high bulk modulus and remarkable electrical properties. However, NMNs can only be synthesized under extreme conditions of ultrahigh pressure and temperature, and nanoscaled NMNs have not been reported. In this work, as typical NMNs, PtNx nanoparticles were synthesized at 5 GPa and 750 K by the method of plasma-assisted laser-heating diamond anvil cell. The significantly reduced synthesis condition benefited from the ingenious design of the precursor and the remarkable chemical activity of the ultrafine Pt nanoparticles. This study, combining nanomaterials with high-pressure and -temperature (HPHT) techniques, provides a novel process for the preparation of NMN nanomaterials, and a new direction for the synthesis of superhard materials.
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A multicellular organism's development is coupled with cellular self-organization, which is regulated by cell-cell interactions and cell-extracellular matrix (ECM) crosstalk. Testicular cells from different species such as mouse, rat, and porcine can self-organize into seminiferous tubules both in vitro and in vivo, but the understanding of the functional role of the ECM during this process is limited. Here, it is shown that mouse testicular cells encapsulated with the biomaterial Matrigel can self-organize into seminiferous tubules with blood-testis barrier (BTB) formation and Leydig cell differentiation. By varying the encapsulation method, a combination of sodium alginate and collagen is used to promote reorganization of seminiferous tubules, which resemble those in vivo. In addition, the self-organization ability of testicular cells declines with advanced cell age, and those germ cells play a pivotal role in this process. These findings will be helpful to understand the self-organization process of testicular cells and provide insights for the reconstruction of testes.
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Materiales Biocompatibles/farmacología , Diferenciación Celular , Células Inmovilizadas/metabolismo , Matriz Extracelular/metabolismo , Células Intersticiales del Testículo/metabolismo , Túbulos Seminíferos/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos ICR , Ratones Desnudos , Ratas , PorcinosRESUMEN
BACKGROUND: The status of lymph nodes in early gastric cancer is critical to make further clinical treatment decision, but the prediction of lymph node metastasis remains difficult before operation. This study aimed to develop a nomogram that contained preoperative factors to predict lymph node metastasis in early gastric cancer patients. METHODS: This study analyzed the clinicopathologic features of 823 early gastric cancer patients who underwent gastrectomy retrospectively, among which 596 patients were recruited in the training cohort and 227 patients in the independent validation cohort. Significant risk factors in univariate analysis were further identified to be independent variables in multivariable logistic regression analysis, which were then incorporated in and presented with a nomogram. And internal and external validation curves were plotted to evaluate the discrimination of the nomogram. RESULTS: Totally, six independent predictors, including the tumor size, macroscopic features, histology differentiation, P53, carbohydrate antigen 19-9, and computed tomography-reported lymph node status, were enrolled in the nomogram. Both the internal validation in the training cohort and the external validation in the validation cohort showed the nomogram had good discriminations, with a C-index of 0.82 (95%CI, 0.78 to 0.86) and 0.77 (95%CI, 0.60 to 0.94) respectively. CONCLUSIONS: Our study developed a new nomogram which contained the most common and significant preoperative risk factors for lymph node metastasis in patients with early gastric cancer. The nomogram can identify early gastric cancer patients with the high probability of lymph node metastasis and help clinicians make more appropriate decisions in clinical practice.