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1.
Nature ; 632(8024): 429-436, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38987599

RESUMEN

Tumours can obtain nutrients and oxygen required to progress and metastasize through the blood supply1. Inducing angiogenesis involves the sprouting of established vessel beds and their maturation into an organized network2,3. Here we generate a comprehensive atlas of tumour vasculature at single-cell resolution, encompassing approximately 200,000 cells from 372 donors representing 31 cancer types. Trajectory inference suggested that tumour angiogenesis was initiated from venous endothelial cells and extended towards arterial endothelial cells. As neovascularization elongates (through angiogenic stages SI, SII and SIII), APLN+ tip cells at the SI stage (APLN+ TipSI) advanced to TipSIII cells with increased Notch signalling. Meanwhile, stalk cells, following tip cells, transitioned from high chemokine expression to elevated TEK (also known as Tie2) expression. Moreover, APLN+ TipSI cells not only were associated with disease progression and poor prognosis but also hold promise for predicting response to anti-VEGF therapy. Lymphatic endothelial cells demonstrated two distinct differentiation lineages: one responsible for lymphangiogenesis and the other involved in antigen presentation. In pericytes, endoplasmic reticulum stress was associated with the proangiogenic BASP1+ matrix-producing pericytes. Furthermore, intercellular communication analysis showed that neovascular endothelial cells could shape an immunosuppressive microenvironment conducive to angiogenesis. This study depicts the complexity of tumour vasculature and has potential clinical significance for anti-angiogenic therapy.


Asunto(s)
Células Endoteliales , Neoplasias , Neovascularización Patológica , Análisis de la Célula Individual , Humanos , Presentación de Antígeno , Comunicación Celular , Diferenciación Celular , Linaje de la Célula , Progresión de la Enfermedad , Estrés del Retículo Endoplásmico , Células Endoteliales/citología , Células Endoteliales/inmunología , Células Endoteliales/metabolismo , Linfangiogénesis , Neoplasias/irrigación sanguínea , Neoplasias/clasificación , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neovascularización Patológica/patología , Pericitos/patología , Pericitos/citología , Pericitos/metabolismo , Pronóstico , Receptores Notch/metabolismo , Transducción de Señal , Microambiente Tumoral , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Pez Cebra
2.
Nature ; 611(7936): 485-490, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36224388

RESUMEN

Lithium-ion batteries with nickel-rich layered oxide cathodes and graphite anodes have reached specific energies of 250-300 Wh kg-1 (refs. 1,2), and it is now possible to build a 90 kWh electric vehicle (EV) pack with a 300-mile cruise range. Unfortunately, using such massive batteries to alleviate range anxiety is ineffective for mainstream EV adoption owing to the limited raw resource supply and prohibitively high cost. Ten-minute fast charging enables downsizing of EV batteries for both affordability and sustainability, without causing range anxiety. However, fast charging of energy-dense batteries (more than 250 Wh kg-1 or higher than 4 mAh cm-2) remains a great challenge3,4. Here we combine a material-agnostic approach based on asymmetric temperature modulation with a thermally stable dual-salt electrolyte to achieve charging of a 265 Wh kg-1 battery to 75% (or 70%) state of charge in 12 (or 11) minutes for more than 900 (or 2,000) cycles. This is equivalent to a half million mile range in which every charge is a fast charge. Further, we build a digital twin of such a battery pack to assess its cooling and safety and demonstrate that thermally modulated 4C charging only requires air convection. This offers a compact and intrinsically safe route to cell-to-pack development. The rapid thermal modulation method to yield highly active electrochemical interfaces only during fast charging has important potential to realize both stability and fast charging of next-generation materials, including anodes like silicon and lithium metal.

3.
J Virol ; 98(9): e0113224, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39194294

RESUMEN

The 5' untranslated region (5'UTR) of many positive-stranded RNA viruses contain functional regulatory sequences. Here, we show that the porcine reproductive and respiratory syndrome virus (PRRSV), a member of arteriviruses, harbors small upstream open reading frames (uORFs) in its 5'UTR. Bioinformatics analysis shows that this feature is relatively well conserved among PRRSV strains and Arteriviridae. We also identified a uORF, namely uORF2, in the PRRSV strain JXwn06, that possesses translational activity and exerts a suppressive effect on the expression of the primary ORF evidenced by in vitro reporter assays. We tested its importance via reverse genetics by introducing a point mutation into the PRRSV infectious cDNA clone to inactivate the start codon of uORF2. The recovered mutant virus Mut2 surprisingly replicated to the same level as the wild-type virus (WT), but induced a higher level of inflammatory cytokines (e.g., TNF-α, IL-1ß, and IL-6) both in vitro and in animal experiments, correlating well with more severe lung injury and higher death rate. In line with this, over-expression of uORF2 in transfected cells significantly inhibited poly(I:C)-induced expression of inflammatory cytokines. Together, our data support the idea that uORF2 encodes a novel, functional regulator of PRRSV virulence despite of its short size. IMPORTANCE: PRRSV has remained a major challenge to the world swine industry, but we still do not know much about its biology and pathogenesis. Here, we provide evidence to show that the 5'UTR of PRRSV strain JXwn06 harbors a functional uORF that has the coding capacity and regulates induction of inflammation as demonstrated by in vitro assays and animal experiment. The findings reveal a novel viral factor that regulates cellular inflammation and provide insight into the understanding of PRRSV pathogenesis.


Asunto(s)
Regiones no Traducidas 5' , Sistemas de Lectura Abierta , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Animales , Regiones no Traducidas 5'/genética , Porcinos , Síndrome Respiratorio y de la Reproducción Porcina/virología , Replicación Viral , Inflamación/virología , Línea Celular , Citocinas/metabolismo , Citocinas/genética
4.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38189544

RESUMEN

With the development of spatially resolved transcriptomics technologies, it is now possible to explore the gene expression profiles of single cells while preserving their spatial context. Spatial clustering plays a key role in spatial transcriptome data analysis. In the past 2 years, several graph neural network-based methods have emerged, which significantly improved the accuracy of spatial clustering. However, accurately identifying the boundaries of spatial domains remains a challenging task. In this article, we propose stAA, an adversarial variational graph autoencoder, to identify spatial domain. stAA generates cell embedding by leveraging gene expression and spatial information using graph neural networks and enforces the distribution of cell embeddings to a prior distribution through Wasserstein distance. The adversarial training process can make cell embeddings better capture spatial domain information and more robust. Moreover, stAA incorporates global graph information into cell embeddings using labels generated by pre-clustering. Our experimental results show that stAA outperforms the state-of-the-art methods and achieves better clustering results across different profiling platforms and various resolutions. We also conducted numerous biological analyses and found that stAA can identify fine-grained structures in tissues, recognize different functional subtypes within tumors and accurately identify developmental trajectories.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Análisis por Conglomerados , Redes Neurales de la Computación
5.
Brief Bioinform ; 24(3)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37080761

RESUMEN

Advancing spatially resolved transcriptomics (ST) technologies help biologists comprehensively understand organ function and tissue microenvironment. Accurate spatial domain identification is the foundation for delineating genome heterogeneity and cellular interaction. Motivated by this perspective, a graph deep learning (GDL) based spatial clustering approach is constructed in this paper. First, the deep graph infomax module embedded with residual gated graph convolutional neural network is leveraged to address the gene expression profiles and spatial positions in ST. Then, the Bayesian Gaussian mixture model is applied to handle the latent embeddings to generate spatial domains. Designed experiments certify that the presented method is superior to other state-of-the-art GDL-enabled techniques on multiple ST datasets. The codes and dataset used in this manuscript are summarized at https://github.com/narutoten520/SCGDL.


Asunto(s)
Aprendizaje Profundo , Transcriptoma , Teorema de Bayes , Perfilación de la Expresión Génica , Comunicación Celular
6.
Bioinformatics ; 40(1)2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38243703

RESUMEN

MOTIVATION: Spatial clustering is essential and challenging for spatial transcriptomics' data analysis to unravel tissue microenvironment and biological function. Graph neural networks are promising to address gene expression profiles and spatial location information in spatial transcriptomics to generate latent representations. However, choosing an appropriate graph deep learning module and graph neural network necessitates further exploration and investigation. RESULTS: In this article, we present GRAPHDeep to assemble a spatial clustering framework for heterogeneous spatial transcriptomics data. Through integrating 2 graph deep learning modules and 20 graph neural networks, the most appropriate combination is decided for each dataset. The constructed spatial clustering method is compared with state-of-the-art algorithms to demonstrate its effectiveness and superiority. The significant new findings include: (i) the number of genes or proteins of spatial omics data is quite crucial in spatial clustering algorithms; (ii) the variational graph autoencoder is more suitable for spatial clustering tasks than deep graph infomax module; (iii) UniMP, SAGE, SuperGAT, GATv2, GCN, and TAG are the recommended graph neural networks for spatial clustering tasks; and (iv) the used graph neural network in the existent spatial clustering frameworks is not the best candidate. This study could be regarded as desirable guidance for choosing an appropriate graph neural network for spatial clustering. AVAILABILITY AND IMPLEMENTATION: The source code of GRAPHDeep is available at https://github.com/narutoten520/GRAPHDeep. The studied spatial omics data are available at https://zenodo.org/record/8141084.


Asunto(s)
Algoritmos , Perfilación de la Expresión Génica , Redes Neurales de la Computación , Programas Informáticos , Análisis por Conglomerados
7.
J Am Chem Soc ; 146(10): 6461-6465, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38415580

RESUMEN

A consensus view in catalysis is that a higher density of catalytically active sites indicates a higher reaction rate. Using molecular dynamics simulations capable of mimicking the electrochemical formation of gas molecules, we herein demonstrate that this view is problematic for electrocatalytic gas production. Our simulation results show that a higher density of catalytic active sites does not necessarily indicate a higher reaction rate─a high density of active sites could lead to a reduction in the rate of reaction. Further analysis reveals that this abnormal phenomenon is ascribed to aggregation of the produced gas molecules near catalytic sites. This work challenges the consensus view and lays the groundwork for better developing gas-producing reaction electrocatalysts.

8.
BMC Biotechnol ; 24(1): 15, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521922

RESUMEN

BACKGROUND: Removal of heavy metals from water and soil is a pressing challenge in environmental engineering, and biosorption by microorganisms is considered as one of the most cost-effective methods. In this study, the metal-binding proteins MerR and ChrB derived from Cupriavidus metallidurans were separately expressed in Escherichia coli BL21 to construct adsorption strains. To improve the adsorption performance, surface display and codon optimization were carried out. RESULTS: In this study, we constructed 24 adsorption engineering strains for Hg2+ and Cr6+, utilizing different strategies. Among these engineering strains, the M'-002 and B-008 had the strongest heavy metal ion absorption ability. The M'-002 used the flexible linker and INPN to display the merRopt at the surface of the E. coli BL21, whose maximal adsorption capacity reached 658.40 µmol/g cell dry weight under concentrations of 300 µM Hg2+. And the B-008 overexpressed the chrB in the intracellular, its maximal capacity was 46.84 µmol/g cell dry weight under concentrations 500 µM Cr6+. While in the case of mixed ions solution (including Pb2+, Cd2+, Cr6+ and Hg2+), the total amount of ions adsorbed by M'-002 and B-008 showed an increase of up to 1.14- and 4.09-folds, compared to the capacities in the single ion solution. CONCLUSION: The construction and optimization of heavy metal adsorption strains were carried out in this work. A comparison of the adsorption behavior between single bacteria and mixed bacteria systems was investigated in both a single ion and a mixed ion environment. The Hg2+ absorption capacity is reached the highest reported to date with the engineered strain M'-002, which displayed the merRopt at the surface of chassis cell, indicating the strain's potential for its application in practical environments.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Proteínas Portadoras/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Iones/metabolismo , Mercurio/metabolismo , Metales Pesados/metabolismo , Contaminantes Químicos del Agua/metabolismo
9.
Nat Mater ; 22(9): 1078-1084, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37537352

RESUMEN

Two-dimensional (2D) semiconductors are promising channel materials for next-generation field-effect transistors (FETs). However, it remains challenging to integrate ultrathin and uniform high-κ dielectrics on 2D semiconductors to fabricate FETs with large gate capacitance. We report a versatile two-step approach to integrating high-quality dielectric film with sub-1 nm equivalent oxide thickness (EOT) on 2D semiconductors. Inorganic molecular crystal Sb2O3 is homogeneously deposited on 2D semiconductors as a buffer layer, which forms a high-quality oxide-to-semiconductor interface and offers a highly hydrophilic surface, enabling the integration of high-κ dielectrics via atomic layer deposition. Using this approach, we can fabricate monolayer molybdenum disulfide-based FETs with the thinnest EOT (0.67 nm). The transistors exhibit an on/off ratio of over 106 using an ultra-low operating voltage of 0.4 V, achieving unprecedently high gating efficiency. Our results may pave the way for the application of 2D materials in low-power ultrascaling electronics.

10.
Hum Reprod ; 39(9): 2079-2088, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39008821

RESUMEN

STUDY QUESTION: Does the concurrent type 2 diabetes mellitus (T2DM) aggravate the features and prognosis of PCOS in patients undergoing sleeve gastrectomy (SG)? SUMMARY ANSWER: For patients undergoing SG with obesity, concurrent T2DM is associated with aggravated metabolic but milder reproductive features of PCOS and did not attenuate the resumption of regular menstruation for up to 1 year after surgery. WHAT IS KNOWN ALREADY: Women with T2DM have an increased risk of PCOS. However, whether concurrent T2DM further increases the disease burden and treatment difficulty of PCOS in patients with obesity requires further investigation. STUDY DESIGN, SIZE, DURATION: This was a single-center, two-arm, prospective, cohort study enrolling a total of 329 women with PCOS and scheduled for SG because of obesity at an university-affiliated hospital between January 2020 and August 2023, with a 1-year follow-up after surgery. PARTICIPANTS/MATERIALS, SETTING, METHODS: Comparisons were made between patients with T2DM (PCOS+T2DM) and without (PCOS) to examine the impact of T2DM on the metabolic, reproductive, and psychological features of PCOS. The follow-up data of weight loss and menstruation were analyzed to determine the impact of T2DM on PCOS prognosis for up to 1 year after SG. MAIN RESULTS AND THE ROLE OF CHANCE: After controlling for confounders, patients in the PCOS+T2DM group (n = 98) showed more severe insulin resistance, glucose intolerance, dyslipidemia, and non-alcoholic fatty liver disease (NAFLD) (NAFLD activity score 4.31 ± 1.15 versus 3.52 ± 1.42, P < 0.001) than those in the PCOS group (n = 149). In addition, the PCOS+T2DM group had a lower level of total testosterone (1.63 ± 0.69 versus 1.82 ± 0.76, P = 0.045), a lower ratio between luteinizing hormone and follicle-stimulating hormone (median 1.48 versus 1.68, P = 0.030), and a lower proportion of patients with polycystic ovarian morphology (88% versus 96%, P = 0.022) than the PCOS group. As a result, the two groups differed significantly in terms of the Rotterdam classification of PCOS (P = 0.009). No significant difference was detected by group in the psychological features of PCOS except a lower degree of emotional eating in the PCOS+T2DM group (P = 0.001). Although the PCOS+T2DM group took longer to resume regular menstruation after SG (P = 0.037), the two groups had similar proportions of patients with regular menstruation (85% versus 87%, P = 0.758) 1 year after SG, which was further confirmed by subgroup analyses by body mass index. LIMITATIONS, REASONS FOR CAUTION: The prognosis of PCOS after SG mainly focused on the results of menstruation rather than a complete evaluation of the remission of the disease. WIDER IMPLICATIONS OF THE FINDINGS: Our study showed that, for patients with obesity, concurrent T2DM is associated with aggravated metabolic but milder reproductive features of PCOS and did not attenuate the resumption of regular menstruation for up to 1 year after surgery. Our study also highlights the need for high-quality studies with a more comprehensive evaluation of the impact of T2DM on the prognosis of patients with PCOS after SG. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the National Natural Science Foundation of China Grants (82100853), the Natural Science Foundation of Shandong Province of China (ZR2021QH028), and the Clinical Research Project of Shandong University (2020SDUCRCC024). The authors have no conflicts of interest. TRIAL REGISTRATION: Chinese Clinical Trial Registry with No. ChiCTR1900026845.


Asunto(s)
Diabetes Mellitus Tipo 2 , Gastrectomía , Síndrome del Ovario Poliquístico , Humanos , Femenino , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/psicología , Síndrome del Ovario Poliquístico/cirugía , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/cirugía , Diabetes Mellitus Tipo 2/psicología , Adulto , Gastrectomía/efectos adversos , Gastrectomía/métodos , Estudios Prospectivos , Obesidad/complicaciones , Obesidad/cirugía , Obesidad/psicología , Pronóstico , Pérdida de Peso , Resistencia a la Insulina
11.
J Org Chem ; 89(8): 5498-5510, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38577943

RESUMEN

Reactions allowing chemodivergence prove to be attractive strategies in synthetic organic chemistry. We herein described a highly practical, transition-metal-free, highly regioselective and chemodivergent cascade reaction controlled by fluorine sources, which involved a [3 + 2] cycloaddition or C-arylation process between aryne precursors and 3-aminomaleimides. These two pathways led to a wide scope of structurally diverse pyrrolo[3,4-b]indoles (19 examples) and 3-arylated maleimides (25 examples) in good-to-excellent yields. Furthermore, the reaction could be scaled up, and several synthetic transformations were accomplished for the preparation of functionalized molecules and might provide new opportunities for the discovery of N-heterocyclic drugs.

12.
Inorg Chem ; 63(32): 15090-15097, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39087570

RESUMEN

The conversion of CO2 into useful chemicals via photocatalysts is a promising strategy for resolving the environmental problems caused by the addition of CO2. Herein, a series of composite photocatalysts MOP@TpPa-CH3 based on MOP-NH2 and TpPa-CH3 through covalent bridging have been prepared via a facile room-temperature evaporation method and employed for photocatalytic CO2 reduction. The photocatalytic performances of MOP@TpPa-CH3 are greater than those of TpPa-CH3 and MOP-NH2, where the CO generation rate of MOP@TpPa-CH3 under 10% CO2 still reaches 119.25 µmol g-1 h-1, which is 2.18 times higher than that under pure CO2 (54.74 µmol g-1 h-1). To investigate the structural factors affecting the photocatalytic activity, MOP@TBPa-CH3 without C═O groups is synthesized, and the photoreduction performance is also evaluated. The controlling experimental results demonstrate that the excellent photoreduction CO2 performance of MOP@TpPa-CH3 in a 10% CO2 atmosphere is due to the presence of C═O groups in TpPa-CH3. This work offers a new design and construction strategy for novel MOP@COF composites.

13.
Phys Chem Chem Phys ; 26(5): 3950-3962, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38250964

RESUMEN

To elucidate the valence state effect of doping cations, Li+, Mg2+, Cr3+, Zr4+ and Nb5+ with radii similar to Sn4+ (CN = 6) were chosen to dope tetragonal SnO2. Cr3+, Zr4+ and Nb5+ can enter the SnO2 lattice to produce solid solutions, thus creating more surface defects. However, Li+ and Mg2+ can only stay on the SnO2 surface as nitrates, thus suppressing the surface defects. The rich surface defects facilitate the generation of active O2-/Oδ- and acid sites on the solid solution catalysts, hence improving the reactivity. On the solid solution catalysts active for propane combustion, several reactive intermediates can be formed, but are negligible on those with low activity. It is confirmed that for propane combustion, surface acid sites play a more vital role than active oxygen sites. Nevertheless, for CO oxidation, the active oxygen sites play a more vital role than the acid sites.

14.
Med Sci Monit ; 30: e944963, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39205372

RESUMEN

BACKGROUND Long-term clinical practice has suggested a possible association between ossification of cervical ligament (OCL) and primary osteoporosis (POP). However, there is a lack of relevant research data. This study aimed to clarify the potential relationship between OCL and POP, and propose new strategies for preventing the onset of POP. MATERIAL AND METHODS The study involved 107 patients. The patients' diagnosis included OCL (ossification of the posterior longitudinal ligament, ossification of the ligamentum flavum, and ossification of the nuchal ligament) and POP. Bone mineral density (BMD), types of OCL, types of ossification of posterior longitudinal ligament, age, sex, serum calcium, serum phosphorus, alkaline phosphatase, type I collagen amino-terminal extension peptide, type I collagen degradation products, osteocalcin N-terminal molecular fragments, 25-hydroxyvitamin D, and history of taking steroid drugs were collected. SPSS24.0 and GraphPad Prism 8 were used to obtain the risk factors for POP. RESULTS One-way analysis of variance found that OCL, ossification of posterior longitudinal ligament, alkaline phosphatase, and osteocalcin N-terminal molecular fragments had statistical significance on BMD of the femoral neck (P<0.05). The independent sample t test showed that patient sex had statistical significant effect on BMD (femoral neck) (P=0.036). Incorporating the above factors into multiple linear regression analysis, it was found that OCL, alkaline phosphatase, and osteocalcin N-terminal molecular fragments were risk factors affecting BMD of femoral neck (P<0.05). CONCLUSIONS OCL, osteocalcin N-terminal molecular fragments, and alkaline phosphatase are risk factors for POP.


Asunto(s)
Fosfatasa Alcalina , Densidad Ósea , Osificación del Ligamento Longitudinal Posterior , Osteocalcina , Osteoporosis , Humanos , Femenino , Masculino , Factores de Riesgo , Persona de Mediana Edad , Fosfatasa Alcalina/sangre , Fosfatasa Alcalina/metabolismo , Anciano , Osteocalcina/metabolismo , Osteocalcina/sangre , Adulto , Osificación Heterotópica , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Vitamina D/sangre , Ligamentos , Cuello Femoral/metabolismo , Vértebras Cervicales
15.
Molecules ; 29(14)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39065002

RESUMEN

The metal-free porphyrins protonation has gained interest over five decades because its structure modification and hardly monoacid intermediate isolation. Here, upon the hydrogen atom abstraction processes, one step diproptonated H3STTP(BF4)2 (STTP = 5,10,15,20-tetraphenyl-21-thiaporphyrin) (3) and stepwise protonated HS2TTPSbCl6 (5) and diprotonated H2S2TTP(BF4)2 (6) (S2TTP = 5,10,15,20-tetraphenyl-21,23-thiaporphyrin) compounds were obtained using HSTTP and S2TTP with oxidants. The closed-shell protonated compounds were fully characterized using XRD, UV-vis, IR and NMR spectra. In addition, the reduced 19π compounds [K(2,2,2)]HSTTP (2) and [K(2,2,2)]S2TTP (7) were synthesized by the ligands with reductant KC8 in THF solution. These two open-shell compounds were characterized with UV-vis, IR and EPR spectroscopies. The semiempirical ZINDO/S method was employed to analyze the HOMO/LUMO gap lever and identify the electronic transitions of the UV-vis spectra of the closed- and open-shell porphyrin compounds.

16.
Zhongguo Zhong Yao Za Zhi ; 49(2): 354-360, 2024 Jan.
Artículo en Zh | MEDLINE | ID: mdl-38403311

RESUMEN

This study aimed to examine the morphological, physiological, and biochemical alterations occurring in Notopterygium incisum seeds throughout their developmental stages, with the objective of establishing a theoretical foundation for the cultivation of superior quality seeds. The experimental materials utilized in this study were the seeds of N. incisum at various stages of development following anthesis. Through the employment of morphological observation and plant physiology techniques, the external morphology, nutrients, enzyme activity, and endogenous hormones of the seeds were assessed. The results revealed a transition in seed coat color from light green to brown during the growth and development of N. incisum seeds. Additionally, as the seeds matured, a decrease in water content was observed. Conversely, starch content exhibited a progressive increase, while sucrose content displayed fluctuations. At 7 days after anthesis, the soluble sugar content attained its highest level of 4.52 mg·g~(-1), whereas the soluble protein content reached its maximum of 6.00 mg·g~(-1) at 14 days after anthesis and its minimum of 4.94 mg·g~(-1) at 42 days after anthesis. The activity of superoxide dismutase(SOD) exhibited an initial increase, followed by a decrease, and eventually reached a stable state. Conversely, the activities of catalase(CAT) and peroxidase(POD) demonstrated a decrease initially, followed by an increase, and then another decrease. The levels of the four endogenous hormones, namely gibberellin(GA_3), zeatin riboside(ZR), auxin(IAA), and abscisic acid(ABA), in the seeds displayed significant variations, with IAA and ABA exhibiting considerably higher levels compared to the other hormones. The levels of plant growth-promoting hormones, represented by IAA, generally displayed a pattern of initial increase followed by a subsequent decrease during seed development, while the plant growth-inhibiting hormone ABA showed the opposite trend. The findings indicate that the alterations in nutrient composition, antioxidant enzyme activity, and endogenous hormone levels vary throughout the maturation process of N. incisum seeds. These observations hold relevance for the cultivation of N. incisum seeds.


Asunto(s)
Giberelinas , Reguladores del Crecimiento de las Plantas , Ácido Abscísico , Semillas , Hormonas/metabolismo , Germinación/fisiología
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(1): 160-167, 2024 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-38403617

RESUMEN

Assisting immobile individuals with regular repositioning to adjust pressure distribution on key prominences such as the back and buttocks is the most effective measure for preventing pressure ulcers. However, compared to active self-repositioning, passive assisted repositioning results in distinct variations in force distribution on different body parts. This incongruity can affect the comfort of repositioning and potentially lead to a risk of secondary injury, for certain trauma or critically ill patients. Therefore, it is of considerable practical importance to study the passive turning comfort and the optimal turning strategy. Initially, in this study, the load-bearing characteristics of various joints during passive repositioning were examined, and a wedge-shaped airbag configuration was proposed. The airbags coupled layout on the mattress was equivalently represented as a spring-damping system, with essential model parameters determined using experimental techniques. Subsequently, different assisted repositioning strategies were devised by adjusting force application positions and sequences. A human-mattress force-coupled simulation model was developed based on rigid human body structure and equivalent flexible springs. This model provided the force distribution across the primary pressure points on the human body. Finally, assisted repositioning experiments were conducted with 15 participants. The passive repositioning effectiveness and pressure redistribution was validated based on the simulation results, experimental data, and questionnaire responses. Furthermore, the mechanical factors influencing comfort during passive assisted repositioning were elucidated, providing a theoretical foundation for subsequent mattress design and optimization of repositioning strategies.


Asunto(s)
Úlcera por Presión , Humanos , Úlcera por Presión/prevención & control , Lechos
18.
J Cell Physiol ; 238(1): 257-273, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36436135

RESUMEN

Although neuronal Toll-like receptors (TLRs) (e.g., TLR2, TLR3, and TLR7) have been implicated in itch sensation, the roles of keratinocyte TLRs in chronic itch are elusive. Herein, we evaluated the roles of keratinocyte TLR2 and TLR7 in chronic itch under dry skin and psoriasis conditions, which was induced by either acetone-ether-water treatment or 5% imiquimod cream in mice, respectively. We found that TLR2 and TLR7 signaling were significantly upregulated in dry skin and psoriatic skin in mice. Chronic itch and epidermal hyperplasia induced by dry skin or psoriasis were comparably reduced in TLR2 and TLR7 knockout mice. In the dry skin model, the enhanced messenger RNA (mRNA) expression levels of pruritic CXCL1/2, IL-31, IL-33, ST2, IL-6, IL-17A, TNF-α, and IFN-γ were inhibited in TLR2-/- mice, while CXCL2, IL-31, and IL-6 were inhibited in TLR7-/- mice. In psoriasis model, the enhanced mRNA expression levels of pruritic CXCL1/2, IL-31, IL-33, ST2, IL-6, and TNF-α were inhibited in TLR2-/- mice, while CXCL1/2, IL-31, IL-33, ST2, IL-6, IL-17A, and TNF-α were inhibited in TLR7-/- mice. Incubation with Staphylococcus aureus (S. aureus) peptidoglycan (PGN-SA) (a TLR2 agonist), imiquimod (a TLR7 agonist), and miR142-3p (a putative TLR7 agonist) were sufficient to upregulate the expression of pruritic cytokines or chemokines in cultured keratinocyte HaCaT cells. Finally, pharmacological blockade of C-X-C Motif Chemokine Receptor 1/2 and high mobility group box protein 1 dose-dependently attenuated acute and chronic itch in mice. Together, these results indicate that keratinocyte TLR2 and TLR7 signaling pathways are distinctly involved in the pathogenesis of chronic itch.


Asunto(s)
Quimiocinas , Citocinas , Prurito , Psoriasis , Receptor Toll-Like 2 , Receptor Toll-Like 7 , Animales , Ratones , Citocinas/metabolismo , Imiquimod/efectos adversos , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-17 , Interleucina-33 , Interleucina-6 , Queratinocitos/metabolismo , Psoriasis/tratamiento farmacológico , ARN Mensajero , Receptor Toll-Like 2/genética , Receptor Toll-Like 7/genética , Factor de Necrosis Tumoral alfa/efectos adversos , Modelos Animales de Enfermedad , Ratones Noqueados , Células HaCaT , Humanos
19.
Small ; 19(46): e2303517, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37475514

RESUMEN

Cancer and its metastasis/recurrence still threaten human health, despite various advanced treatments being employed. It is of great significance to develop simple drug formulations to enhance the efficacy and synergistic integration of various monotherapies. Herein, DMXAA, a vasodestructive agent with cGAS-STING stimulation capacity, is integrated with polyethylene glycol grafted poly (lactic-co-glycolic) acid co-polymer (PLGA-PEG), obtaining PLGA-PEG/DMXAA (PPD) nanoparticles to induce the tumor-specific vascular destruction for multiple synergistic therapies of cancer. PPD could induce the formation of blood clots in the tumor after intravenous injection, which subsequently mediate photothermal therapy and further promote the release of oxygen for enhanced radiotherapy. Meanwhile, the enhanced vascular injury can induce perfect starvation therapy of tumor. More importantly, PPD-mediated therapies could trigger potent systemic anti-tumor immunity via inducing the immunogenic death of tumor cells and activating the cGAS-STING pathway. Together with anti-PD-L1, PPD-mediated therapies could not only remove the primary tumors, but also effectively eliminate the distant tumors, metastasis, and recurrence. Therefore, the modulation of tumor composition induced by a single drug-loaded nano-micelle could be utilized to enhance the therapeutic effect of multiple treatments for synergistic and systemic antitumor response, providing a practical strategy for cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Micelas , Neoplasias/tratamiento farmacológico , Polietilenglicoles , Inmunoterapia
20.
Blood ; 137(13): 1804-1817, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33513603

RESUMEN

Lysosome-related organelles (LROs) are a category of secretory organelles enriched with ions such as calcium, which are maintained by ion transporters or channels. Homeostasis of these ions is important for LRO biogenesis and secretion. Hermansky-Pudlak syndrome (HPS) is a recessive disorder with defects in multiple LROs, typically platelet dense granules (DGs) and melanosomes. However, the underlying mechanism of DG deficiency is largely unknown. Using quantitative proteomics, we identified a previously unreported platelet zinc transporter, transmembrane protein 163 (TMEM163), which was significantly reduced in BLOC-1 (Dtnbp1sdy and Pldnpa)-, BLOC-2 (Hps6ru)-, or AP-3 (Ap3b1pe)-deficient mice and HPS patients (HPS2, HPS3, HPS5, HPS6, or HPS9). We observed similar platelet DG defects and higher intracellular zinc accumulation in platelets of mice deficient in either TMEM163 or dysbindin (a BLOC-1 subunit). In addition, we discovered that BLOC-1 was required for the trafficking of TMEM163 to perinuclear DG and late endosome marker-positive compartments (likely DG precursors) in MEG-01 cells. Our results suggest that TMEM163 is critical for DG biogenesis and that BLOC-1 is required for the trafficking of TMEM163 to putative DG precursors. These new findings suggest that loss of TMEM163 function results in disruption of intracellular zinc homeostasis and provide insights into the pathogenesis of HPS or platelet storage pool deficiency.


Asunto(s)
Plaquetas/patología , Síndrome de Hermanski-Pudlak/patología , Proteínas de la Membrana/metabolismo , Animales , Plaquetas/metabolismo , Síndrome de Hermanski-Pudlak/metabolismo , Humanos , Lisosomas/metabolismo , Lisosomas/patología , Ratones Endogámicos C57BL , Vesículas Secretoras/metabolismo , Vesículas Secretoras/patología , Zinc/metabolismo
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