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1.
Nature ; 612(7938): 92-99, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36261525

RESUMO

The Indo-Pacific Warm Pool (IPWP) exerts a dominant role in global climate by releasing huge amounts of water vapour and latent heat to the atmosphere and modulating upper ocean heat content (OHC), which has been implicated in modern climate change1. The long-term variations of IPWP OHC and their effect on monsoonal hydroclimate are, however, not fully explored. Here, by combining geochemical proxies and transient climate simulations, we show that changes of IPWP upper (0-200 m) OHC over the past 360,000 years exhibit dominant precession and weaker obliquity cycles and follow changes in meridional insolation gradients, and that only 30%-40% of the deglacial increases are related to changes in ice volume. On the precessional band, higher upper OHC correlates with oxygen isotope enrichments in IPWP surface water and concomitant depletion in East Asian precipitation as recorded in Chinese speleothems. Using an isotope-enabled air-sea coupled model, we suggest that on precessional timescales, variations in IPWP upper OHC, more than surface temperature, act to amplify the ocean-continent hydrological cycle via the convergence of moisture and latent heat. From an energetic viewpoint, the coupling of upper OHC and monsoon variations, both coordinated by insolation changes on orbital timescales, is critical for regulating the global hydroclimate.

2.
Am J Physiol Cell Physiol ; 326(4): C1106-C1119, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38344766

RESUMO

Intrauterine infection during pregnancy can enhance uterine contractions. A two-pore K+ channel TREK1 is crucial for maintaining uterine quiescence and reducing contractility, with its properties regulated by pH changes in cell microenvironment. Meanwhile, the sodium hydrogen exchanger 1 (NHE1) plays a pivotal role in modulating cellular pH homeostasis, and its activation increases smooth muscle tension. By establishing an infected mouse model of Escherichia coli (E. coli) and lipopolysaccharide (LPS), we used Western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence to detect changes of TREK1 and NHE1 expression in the myometrium, and isometric recording measured the uterus contraction. The NHE1 inhibitor cariporide was used to explore the effect of NHE1 on TREK1. Finally, cell contraction assay and siRNA transfection were performed to clarify the relationship between NHE1 and TREK1 in vitro. We found that the uterine contraction was notably enhanced in infected mice with E. coli and LPS administration. Meanwhile, TREK1 expression was reduced, whereas NHE1 expression was upregulated in infected mice. Cariporide alleviated the increased uterine contraction and promoted myometrium TREK1 expression in LPS-injected mice. Furthermore, suppression of NHE1 with siRNA transfection inhibited the contractility of uterine smooth muscle cells and activated the TREK1. Altogether, our findings indicate that infection increases the uterine contraction by downregulating myometrium TREK1 in mice, and the inhibition of TREK1 is attributed to the activation of NHE1.NEW & NOTEWORTHY Present work found that infection during pregnancy will increase myometrium contraction. Infection downregulated NHE1 and followed TREK1 expression and activation decrease in myometrium, resulting in increased myometrium contraction.


Assuntos
Guanidinas , Lipopolissacarídeos , Miométrio , Canais de Potássio de Domínios Poros em Tandem , Trocador 1 de Sódio-Hidrogênio , Sulfonas , Animais , Feminino , Camundongos , Gravidez , Escherichia coli , Lipopolissacarídeos/toxicidade , Miométrio/metabolismo , RNA Interferente Pequeno/metabolismo , Contração Uterina/fisiologia , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Trocador 1 de Sódio-Hidrogênio/metabolismo
3.
J Biol Chem ; 299(10): 105232, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37690690

RESUMO

After adult mammalian central nervous system injury, axon regeneration is extremely limited or absent, resulting in persistent neurological deficits. Axon regeneration failure is due in part to the presence of inhibitory proteins, including NogoA (Rtn4A), from which two inhibitory domains have been defined. When these inhibitory domains are deleted, but an amino-terminal domain is still expressed in a gene trap line, mice show axon regeneration and enhanced recovery from injury. In contrast, when there is no amino-terminal Nogo-A fragment in the setting of inhibitory domain deletion, then axon regeneration and recovery are indistinguishable from WT. These data indicated that an amino-terminal Nogo-A fragment derived from the gene trap might promote axon regeneration, but this had not been tested directly and production of this fragment without gene targeting was unclear. Here, we describe posttranslation production of an amino-terminal fragment of Nogo-A from the intact gene product. This fragment is created by proteolysis near amino acid G214-N215 and levels are enhanced by axotomy. Furthermore, this fragment promotes axon regeneration in vitro and acts cell autonomously in neurons, in contrast to the inhibitory extracellular action of other Nogo-A domains.Proteins interacting with the amino-terminal Nogo-A fragment by immunoprecipitation include HSPA8 (HSC70, HSP7C). Suppression of HSPA8 expression by shRNA decreases axon regeneration from cerebral cortical neurons and overexpression increases axon regeneration. Moreover, the amino-terminal Nogo-A fragment increases HSPA8 chaperone activity. These data provide an explanation for varied results in different gene-targeted Nogo-A mice, as well as revealing an axon regeneration promoting domain of Nogo-A.


Assuntos
Axônios , Proteínas da Mielina , Animais , Camundongos , Axônios/metabolismo , Inibidores do Crescimento/metabolismo , Mamíferos/metabolismo , Proteínas da Mielina/genética , Proteínas da Mielina/metabolismo , Regeneração Nervosa/fisiologia , Proteínas Nogo/genética , Proteínas Nogo/metabolismo , Proteólise , Feminino , Camundongos Endogâmicos C57BL
4.
Reproduction ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39312648

RESUMO

Hypoxia is closely associated with physiological and pathological conditions in the human body, and the myometrium is affected by hypoxic stress during pregnancy and delivery. Autophagy is a catabolic pathway involved in the regulation of apoptosis, proliferation and migration of a variety of cells, which can be activated under hypoxia. However, the mechanism and function of autophagy in uterine smooth muscle cells remained unclear. The aim of this study was to investigate the changes of autophagy in pregnant uterine smooth muscle cells (pUSMCs) under hypoxia and the effect of autophagy on myometrial cells proliferation during pregnancy. In this study, primary uterine smooth muscle cells were isolated from mice in late pregnancy and cultured under normoxic and hypoxic conditions respectively. Western blotting and immunofluorescence were used to detect the expression levels of autophagy-related proteins LC3B, P62, mTOR and p-mTOR under different culture conditions. Cell proliferation was assessed by CCK-8 assay. In addition, 3-Methyladenine (3-MA) was used to inhibit autophagy in hypoxia-treated pUSMCs and MHY1485 was used to activate mTOR. Studies have confirmed that under hypoxic conditions, autophagy is enhanced and cell proliferative viability is reduced in pUSMCs. Autophagy inhibitor 3-MA restored cell proliferation inhibited by hypoxia. Furthermore, hypoxia in pUSMCs led to a downregulation of p-mTOR/mTOR levels. The mTOR activator MHY1485 inhibited autophagy by preventing the binding of autophagosomes to lysosomes and reversed the hypoxia-induced inhibition of cell proliferation. Collectively, our results indicate that hypoxia upregulates autophagy through the mTOR pathway in pUSMCs, thereby inhibiting cell proliferation during pregnancy.

5.
Exp Eye Res ; 241: 109837, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382576

RESUMO

The lens is an avascular tissue, where epithelial cells (LECs) are the primary living cells. The role of LECs-derived exosomes (LEC-exos) is largely unknown. In our study, we determined the anti-angiogenic role of LEC-exos, manifested as regressed retinal neovascularization (NV) using the oxygen-induced retinopathy (OIR), and reduced choroidal NV size and pathological vascular leakage using the laser-induced choroidal neovascularization (laser-induced CNV). Furthermore, the activation and accumulation of microglia were also restricted by LEC-exos. Based on Luminex multiplex assays, the expressions of chemokines such as SCYB16/CXCL16, MCP-1/CCL2, I-TAC/CXCL11, and MIP 3beta/CCL19 were decreased after treatment with LEC-exos. Transwell assays showed that LEC-exos restricted the migration of the mouse microglia cell line (BV2 cells). After incubation with LEC-exos-treated BV2 cells, human umbilical vein endothelial cells (hUVECs) were collected for further evaluation using tube formation, Transwell assays, and 5-ethynyl-2'-deoxyuridine (EDU) assays. Using in vitro experiments, the pro-angiogenic effect of microglia was restricted by LEC-exos. Hence, it was investigated that LEC-exos attenuated ocular NV, which might attribute to the inhibition of microglial activation and accumulation.


Assuntos
Neovascularização de Coroide , Exossomos , Células-Tronco Mesenquimais , Camundongos , Animais , Humanos , Microglia , Exossomos/metabolismo , Angiogênese , Neovascularização Fisiológica/fisiologia , Células Endoteliais da Veia Umbilical Humana , Neovascularização de Coroide/metabolismo
6.
FASEB J ; 37(10): e23192, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37682530

RESUMO

Abnormal ocular neovascularization, a major pathology of eye diseases, leads to severe visual loss. The role of lens epithelial cell (LEC)-derived exosomes (Lec-exo) is largely unknown. Thus, we aimed to investigate whether Lec-exo can inhibit abnormal ocular neovascularization and explore the possible mechanisms. In our study, we proved the first evidence that exosomes derived from LECs attenuated angiogenesis in both oxygen-induced retinopathy and laser-induced choroidal neovascularization mice models. Further in vitro experiments proved that Lec-exo inhibited proliferation, migration, and tube formation capability of human umbilical vein endothelial cells in high glucose condition. Further high-throughput miRNAs sequencing analysis detected that miR-146a-5p was enriched in Lec-exo. Mechanistically, exosomal miR-146a-5p was delivered to endothelial cells and bound to the NRAS coding sequence, which subsequently inactivated AKT/ERK signaling pathway. We successfully elucidated the function of Lec-exo in inhibiting abnormal ocular neovascularization, which may offer a promising strategy for treatment of abnormal ocular neovascularization.


Assuntos
Neovascularização de Coroide , Exossomos , MicroRNAs , Humanos , Animais , Camundongos , Células Epiteliais , Neovascularização de Coroide/genética , Células Endoteliais da Veia Umbilical Humana , MicroRNAs/genética
7.
Biomacromolecules ; 25(5): 3190-3199, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38693753

RESUMO

Intracellular bacteria in dormant states can escape the immune response and tolerate high-dose antibiotic treatment, leading to severe infections. To overcome this challenge, cascade-targeted nanoplatforms that can target macrophages and intracellular bacteria, exhibiting synergetic antibiotic/reactive oxygen species (ROS)/nitric oxide (NO)/immunotherapy, were developed. These nanoplatforms were fabricated by encapsulating trehalose (Tr) and vancomycin (Van) into phosphatidylserine (PS)-coated poly[(4-allylcarbamoylphenylboric acid)-ran-(arginine-methacrylamide)-ran-(N,N'-bisacryloylcystamine)] nanoparticles (PABS), denoted as PTVP. PS on PTVP simulates a signal of "eat me" to macrophages to promote cell uptake (the first-step targeting). After the uptake, the nanoplatform in the acidic phagolysosomes could release Tr, and the exposed phenylboronic acid on the nanoplatform could target bacteria (the second-step targeting). Nanoplatforms can release Van in response to infected intracellular overexpressed glutathione (GSH) and weak acid microenvironment. l-arginine (Arg) on the nanoplatforms could be catalyzed by upregulated inducible nitric oxide synthase (iNOS) in the infected macrophages to generate nitric oxide (NO). N,N'-Bisacryloylcystamine (BAC) on nanoplatforms could deplete GSH, allow the generation of ROS in macrophages, and then upregulate proinflammatory activity, leading to the reinforced antibacterial capacity. This nanoplatform possesses macrophage and bacteria-targeting antibiotic delivery, intracellular ROS, and NO generation, and pro-inflammatory activities (immunotherapy) provides a new strategy for eradicating intracellular bacterial infections.


Assuntos
Antibacterianos , Nanopartículas , Óxido Nítrico , Espécies Reativas de Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Animais , Células RAW 264.7 , Nanopartículas/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Imunoterapia/métodos , Vancomicina/farmacologia , Vancomicina/química , Vancomicina/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Trealose/química , Trealose/farmacologia
8.
Fish Shellfish Immunol ; 148: 109505, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521144

RESUMO

The E11 cell line, derived from striped snakehead fish (Channa striata), possesses a distinctive feature: it is persistently infected with a C-type retrovirus. Notably, it exhibits high permissiveness to piscine nodavirus and the emerging tilapia lake virus (TiLV). Despite its popularity in TiLV research, the absence of genome assembly for the E11 cell line and Channa striata has constrained research on host-virus interactions. This study aimed to fill this gap by sequencing, assembling, and annotating the E11 cell line genome. Our efforts yielded a 600.5 Mb genome including 24 chromosomes with a BUSCO score of 98.8%. In addition, the complete proviral DNA sequence of snakehead retrovirus (SnRV) was identified in the E11 cell genome. Comparative genomic analysis between the E11 cell line and another snakehead species Channa argus revealed the loss of many immune-related gene families in the E11 cell genome, indicating a compromised immune response. We also conducted transcriptome analysis of mock- and TiLV-infected E11 cells, unveiling new perspectives on virus-virus and host-virus interactions. The TiLV infection suppressed the high expression of SnRV in E11 cells, and activated some other endogenous retroviruses. The protein-coding gene comparison revealed a pronounced up-regulation of genes involved in immune response, alongside a down-regulation of genes associated with specific metabolic processes. In summary, the genome assembly and annotation of the E11 cell line provide valuable resources to understand the SnRV and facilitate further studies on nodavirus and TiLV. The RNA-seq profiles shed light on the cellular mechanisms employed by fish cells in response to viral challenges, potentially guiding the development of therapeutic strategies against TiLV in aquaculture. This study also provides the first insights into the viral transcriptome profiles of endogenous SnRV and evading TiLV, enhancing our understanding of host-virus interactions in fish.


Assuntos
Doenças dos Peixes , Tilápia , Vírus , Animais , Retroviridae , Cromossomos , Perfilação da Expressão Gênica/veterinária
9.
Environ Sci Technol ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352010

RESUMO

Soil contamination by multiple metals is a significant concern due to the interlinked mobilization processes. The challenges in comprehending this issue arise from the poorly characterized interaction among different metals and the complexities introduced by spatial and temporal heterogeneity in soil systems. We delved into these complexities by incubating size-fractionated paddy soils under both anaerobic and aerobic conditions, utilizing a combination of techniques for aqueous and colloidal analysis. The contaminated paddy soil predominantly consisted of particles measuring <53, 250-53, and 2000-250 µm, with the <53 µm fractions exhibiting the highest concentrations of multiple metals. Interestingly, despite their higher overall content, the <53 µm fractions released less dissolved metal. Furthermore, glucose enhanced the release of arsenic while simultaneously promoting the sequestration of other metals, such as Pb, Zn, and Cu. Utilizing asymmetric flow field-flow fractionation, we unveiled the presence of both fine (0.3-130 kDa) and large (130-450 nm) colloidal pools, each carrying various metals with different affinities for iron minerals and organic matter. Our results highlighted the pivotal role of the <53 µm fraction as a significant reservoir for multiple metal contaminants in paddy soils, in which the colloidal metals were mainly associated with organic matter. These findings illuminated the size-resolved dynamics of soil metal cycling and provided insights for developing remediation strategies for metal-contaminated soil ecosystems.

10.
Environ Sci Technol ; 58(28): 12430-12440, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38968084

RESUMO

Soil organic carbon (SOC) is pivotal for both agricultural activities and climate change mitigation, and biochar stands as a promising tool for bolstering SOC and curtailing soil carbon dioxide (CO2) emissions. However, the involvement of biochar in SOC dynamics and the underlying interactions among biochar, soil microbes, iron minerals, and fresh organic matter (FOM, such as plant debris) remain largely unknown, especially in agricultural soils after long-term biochar amendment. We therefore introduced FOM to soils with and without a decade-long history of biochar amendment, performed soil microcosm incubations, and evaluated carbon and iron dynamics as well as microbial properties. Biochar amendment resulted in 2-fold SOC accrual over a decade and attenuated FOM-induced CO2 emissions by approximately 11% during a 56-day incubation through diverse pathways. Notably, biochar facilitated microbially driven iron reduction and subsequent Fenton-like reactions, potentially having enhanced microbial extracellular electron transfer and the carbon use efficiency in the long run. Throughout iron cycling processes, physical protection by minerals could contribute to both microbial carbon accumulation and plant debris preservation, alongside direct adsorption and occlusion of SOC by biochar particles. Furthermore, soil slurry experiments, with sterilization and ferrous iron stimulation controls, confirmed the role of microbes in hydroxyl radical generation and biotic carbon sequestration in biochar-amended soils. Overall, our study sheds light on the intricate biotic and abiotic mechanisms governing carbon dynamics in long-term biochar-amended upland soils.


Assuntos
Carbono , Ferro , Microbiologia do Solo , Solo , Solo/química , Ferro/química , Ferro/metabolismo , Carvão Vegetal/química , Dióxido de Carbono/metabolismo
11.
J Nanobiotechnology ; 22(1): 56, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336783

RESUMO

Diabetic retinopathy (DR) is a vision-threatening diabetic complication that is characterized by microvasculature impairment and immune dysfunction. The present study demonstrated that M2 microglia intensively participated in retinal microangiopathy in human diabetic proliferative membranes, mice retinas, retinas of mice with oxygen-induced retinopathy (OIR) mice, and retinas of streptozotocin-induced DR mice. Further in vivo and in vitro experiments showed that exosomes derived from M2 polarized microglia (M2-exo) could reduce pericyte apoptosis and promote endothelial cell proliferation, thereby promoting vascular remodeling and reducing vascular leakage from the diabetic retina. These effects were further enhanced by M2-exo that facilitated M2 polarization of retinal microglia. Collectively, the study demonstrated the capability of M2-exo to induce retinal microvascular remodeling, which may provide a new therapeutic strategy for the treatment of DR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Exossomos , Camundongos , Animais , Humanos , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/etiologia , Remodelação Vascular , Microglia , Retina
12.
Langenbecks Arch Surg ; 409(1): 54, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321184

RESUMO

BACKGROUND: This study was to compare the safety and efficacy of different lymphadenectomy methods in patients with pancreatic head cancer undergoing pancreaticoduodenectomy (PD). MATERIAL AND METHODS: A total of 150 patients were included in this study. Patients were divided into Group A (n = 79), Group B (n = 44), and Group C (n = 27) according to the different lymphadenectomy methods. The clinical endpoint was time to progression (TTP) and overall survival (OS). Postoperative complications of different lymphadenectomy methods were compared respectively. TTP and OS of the three groups were compared by Kaplan-Meier curves. RESULTS: There were no significant differences between the three groups in operative time (P = 0.300), death in the hospital (P = 0.253), postoperative hemorrhage (P = 0.863), postoperative pancreatic fistula (POPF) B/C (P = 0.306), bile leakage (P = 0.215), intestinal fistula (P = 0.177), lymphatic leakage (P = 0.267), delayed gastric emptying [(DGE) (P = 0.283)], ICU stay (P = 0.506), and postoperative hospital stay [(PHS) (P = 0.810)]. Median TTP in Groups B and C was significantly longer than in Group A (log-rank test, A vs B: P = 0.0005, A vs C: P = 0.0001). Median OS between the three groups has no statistical difference (P = 0.1546). CONCLUSIONS: Extended lymphadenectomy methods based on the TRIANGLE do not increase perioperative complications significantly and can effectively delay tumor progression in patients with pancreatic head cancer.


Assuntos
Pâncreas , Neoplasias Pancreáticas , Humanos , Pâncreas/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Fístula Pancreática/etiologia , Complicações Pós-Operatórias/etiologia , Excisão de Linfonodo/métodos
13.
Artigo em Inglês | MEDLINE | ID: mdl-39367704

RESUMO

PURPOSE: To evaluate ocular refractive development, choroidal thickness (ChT) and changes in choroidal blood flow in form-deprived myopia (FDM) Guinea pigs treated with repeated low-level red-light (RLRL) therapy. METHODS: Twenty-eight 3-week-old male tricolour Guinea pigs were randomised into three groups: normal controls (NC, n = 10), form-deprived (FD, n = 10) and red light treated with form-deprivation (RLFD, n = 8). Interocular refraction and axial length (AL) changes were monitored. Optical coherence tomography angiography (OCTA) measured choroidal thickness, vessel area density, vessel skeleton density and blood flow signal intensity (flux) in the choriocapillaris and medium-large vessel layers. The experimental intervention lasted 3 weeks. RESULTS: At week 3, the FD group had higher myopia and longer axial length than the NC group (all p < 0.001). The RLFD group had higher hyperopia and shorter axial length than the FD group (all p < 0.001). At week 1, the NC group had a thicker choroidal thickness than the FD group (p < 0.05). At weeks 2 and 3, the RLFD group had a thicker choroidal thickness than the FD group (p = 0.002, p < 0.001, respectively). Additionally, the NC group had higher vessel area density, vessel skeleton density and flux in the choriocapillaris layer than the FD group at the three follow-up time points (all p < 0.05). At week 3, the vessel skeleton density and flux were higher in the RLFD group than in the FD group (all p < 0.05). Correlation analysis results showed that weekly changes in refraction and choroidal thickness were negatively correlated with changes in axial length (all p < 0.05). Choroidal thickness changes were positively correlated with alterations in the vessel area density, vessel skeleton density and flux in the choriocapillaris layer, as well as vessel skeleton density and flux changes in the medium-large vessel layers (all p < 0.05). CONCLUSIONS: Repeated low-level red-light (RLRL) therapy retards FDM progression in Guinea pigs, potentially through increased choroidal blood flow in the choriocapillaris layer.

14.
World J Surg Oncol ; 22(1): 241, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39245733

RESUMO

BACKGROUND: This study aimed to construct a novel nomogram based on the number of positive lymph nodes to predict the overall survival of patients with pancreatic head cancer after radical surgery. MATERIALS AND METHODS: 2271 and 973 patients in the SEER Database were included in the development set and validation set, respectively. The primary clinical endpoint was OS (overall survival). Univariate and multivariate Cox regression analyses were used to screen independent risk factors of OS, and then independent risk factors were used to construct a novel nomogram. The C-index, calibration curves, and decision analysis curves were used to evaluate the predictive power of the nomogram in the development and validation sets. RESULTS: After multivariate Cox regression analysis, the independent risk factors for OS included age, tumor extent, chemotherapy, tumor size, LN (lymph nodes) examined, and LN positive. A nomogram was constructed by using independent risk factors for OS. The C-index of the nomogram for OS was 0.652 [(95% confidence interval (CI): 0.639-0.666)] and 0.661 (95%CI: 0.641-0.680) in the development and validation sets, respectively. The calibration curves and decision analysis curves proved that the nomogram had good predictive ability. CONCLUSIONS: The nomogram based on the number of positive LN can effectively predict the overall survival of patients with pancreatic head cancer after surgery.


Assuntos
Linfonodos , Nomogramas , Neoplasias Pancreáticas , Programa de SEER , Humanos , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Taxa de Sobrevida , Linfonodos/patologia , Linfonodos/cirurgia , Idoso , Seguimentos , Prognóstico , Fatores de Risco , Metástase Linfática , Pancreatectomia/mortalidade , Estudos Retrospectivos , Adulto
15.
J Integr Neurosci ; 23(8): 156, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39207077

RESUMO

PURPOSE: To investigate the relationship of diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) parameters with dysfunction in acute focal cerebral ischemia (ACI) rabbits. METHODS: The model of ACI in the middle cerebral artery was made using 30 adult male New Zealand rabbits. The dysfunction severities of the ACI rabbits were assessed using Purdy's score. A paired-sample rank sum test was adopted to compare the abnormal signal zone (ASZ) volumes from T2 weighted imaging (T2WI), dynamic susceptibility contrast-enhanced (DSC) imaging, and DWI with a relative cerebral blood flow (rCBF) map; correlations were analyzed between the volume of each ASZ and Purdy's score by Spearman's rank correlation coefficient. The degree of necrotic and apoptotic cells was evaluated in the ASZ from DWI and DSC PWI-DWI mismatch (PDM) zone. Correlations were analyzed between the index of cellular damage and Purdy's score, the volume of ASZs by Spearman's rank correlation coefficient. RESULTS: The ASZ volumes from DSC-PWI and the rCBF maps were larger than those from DWI (p < 0.001 and p < 0.001, respectively); those from the rCBF map (Z = 0.959, p < 0.001) and DSC-PWI (Z = 0.970, p < 0.001) were positively correlated with DWI; a positive correlation was found between Purdy's score and the ASZ volumes from DSC-PWI (Z = 0.889, p < 0.001), DWI (Z = 0.921, p < 0.001), and rCBF (Z = 0.891, p < 0.001). A significant difference was observed between the ASZ from DWI and the PDM zone in terms of the degree of necrotic (p < 0.001) and apoptotic cells (p < 0.001). The degree of cellular damage in the ASZ of DWI and PDM zone had no relationship with Purdy's score and the volumes of ASZs. CONCLUSION: The ASZ volumes from DSC-PWI, rCBF, and particularly DWI reflected the level of dysfunction in rabbits with ACI.


Assuntos
Imagem de Difusão por Ressonância Magnética , Modelos Animais de Doenças , Animais , Coelhos , Masculino , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/patologia , Circulação Cerebrovascular/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imagem de Perfusão/métodos
16.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931789

RESUMO

Joint source-channel coding (JSCC) based on deep learning has shown significant advancements in image transmission tasks. However, previous channel-adaptive JSCC methods often rely on the signal-to-noise ratio (SNR) of the current channel for encoding, which overlooks the neural network's self-adaptive capability across varying SNRs. This paper investigates the self-adaptive capability of deep learning-based JSCC models to dynamically changing channels and introduces a novel method named Channel-Blind JSCC (CBJSCC). CBJSCC leverages the intrinsic learning capability of neural networks to self-adapt to dynamic channels and diverse SNRs without relying on external SNR information. This approach is advantageous, as it is not affected by channel estimation errors and can be applied to one-to-many wireless communication scenarios. To enhance the performance of JSCC tasks, the CBJSCC model employs a specially designed encoder-decoder. Experimental results show that CBJSCC outperforms existing channel-adaptive JSCC methods that depend on SNR estimation and feedback, both in additive white Gaussian noise environments and under slow Rayleigh fading channel conditions. Through a comprehensive analysis of the model's performance, we further validate the robustness and adaptability of this strategy across different application scenarios, with the experimental results providing strong evidence to support this claim.

17.
Int J Mol Sci ; 25(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39000499

RESUMO

General anesthetics may accelerate the neuropathological changes related to Alzheimer's disease (AD), of which amyloid beta (Aß)-induced toxicity is one of the main causes. However, the interaction of general anesthetics with different Aß-isoforms remains unclear. In this study, we investigated the effects of sevoflurane (0.4 and 1.2 maximal alveolar concentration (MAC)) on four Aß species-induced changes on dendritic spine density (DSD) in hippocampal brain slices of Thy1-eGFP mice and multiple epidermal growth factor-like domains 10 (MEGF10)-related astrocyte-mediated synaptic engulfment in hippocampal brain slices of C57BL/6 mice. We found that both sevoflurane and Aß downregulated CA1-dendritic spines. Moreover, compared with either sevoflurane or Aß alone, pre-treatment with Aß isoforms followed by sevoflurane application in general further enhanced spine loss. This enhancement was related to MEGF10-related astrocyte-dependent synaptic engulfment, only in AßpE3 + 1.2 MAC sevoflurane and 3NTyrAß + 1.2 MAC sevoflurane condition. In addition, removal of sevoflurane alleviated spine loss in Aß + sevoflurane. In summary, these results suggest that both synapses and astrocytes are sensitive targets for sevoflurane; in the presence of 3NTyrAß, 1.2 MAC sevoflurane alleviated astrocyte-mediated synaptic engulfment and exerted a lasting effect on dendritic spine remodeling.


Assuntos
Peptídeos beta-Amiloides , Astrócitos , Região CA1 Hipocampal , Espinhas Dendríticas , Camundongos Endogâmicos C57BL , Sevoflurano , Sinapses , Sevoflurano/farmacologia , Animais , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Camundongos , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/citologia , Masculino , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Anestésicos Inalatórios/farmacologia
18.
J Integr Plant Biol ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109980

RESUMO

The programmable nuclease TnpB is significantly smaller than Cas9, can edit genes in medicinal plants, including Artemisia annua, Salvia miltiorrhiza, Scutellaria baicalensis, Isatis indigotica, and Codonopsis pilosula, and has potential uses in molecular breeding to enhance crop yield and quality.

19.
Zhongguo Zhong Yao Za Zhi ; 49(2): 403-411, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403316

RESUMO

Based on the concept of quality by design(QbD), this study optimized the processing technology of Ilicis Rotundae Cortex. According to the processing method and ingredient requirements of Ilicis Rotundae Cortex in the Chinese Pharmacopoeia, the content of syringin and pedunculoside, alcohol extract, fragmentation rate, and moisture content were taken as the critical quality attributes(CQAs). The soaking time, moistening time, and drying time were taken as critical process parameters(CPPs) by single factor tests. The weight coefficients of CQAs were determined by the analytic hierarchy process(AHP)-entropy weighting method, and the comprehensive score was calculated. With the comprehensive score as the response value, Box-Behnken design was employed to establish a mathematical model between CPPs and CQAs, and the design space for the processing of Ilicis Rotundae Cortex was built and verified. The results of ANOVA showed that the mathematical model had the P value below 0.05, the lack of fit greater than 0.05, adjusted R~2=0.910 5, and predicted R~2=0.831 0, which indicated that the proposed model had statistical significance and good prediction performance. Considering the factors in production, the best processing conditions of Ilicis Rotundae Cortex were decoction pieces of about 1 cm soaking for 1 h, moistening for 4 h, and drying at 60-70 ℃ in a blast drier for 2 h. The optimized processing technology of Ilicis Rotundae Cortex was stable and feasible, which can provide a reference for the standardized preparation and stable quality of Ilicis Rotundae Cortex.


Assuntos
Medicamentos de Ervas Chinesas , Casca de Planta , Tecnologia , Etanol
20.
Angew Chem Int Ed Engl ; : e202410017, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39072969

RESUMO

As a fundamental industrial catalytic process, the semihydrogenation of alkynes presents a challenge in striking a balance between activity and selectivity due to the issue of over-hydrogenation. Herein, we develop an efficient catalytic system based on single-atom Pd catalysts supported on boron-containing amorphous zeolites (Pd/AZ-B), achieving the tradeoff breaking between the activity and selectivity for the selective hydrogenation of alkynes. Advanced characterizations and theoretical density functional theory calculations confirm that the incorporated B atoms in the Pd/AZ-B can not only alter the geometric and electronic properties of Pd atoms by controlling the electron migration from Pd but also mitigate the interaction between alkene and the catalyst supports. This boosts the exceptional catalytic efficacy in the semihydrogenation of phenylacetylene to styrene under mild conditions (298 K, 2 bar H2), achieving a recorded turnover frequency (TOF) value of 24198 h-1 and demonstrating 95 % selectivity to styrene at full conversion of phenylacetylene. By comparison, the heteroatom-free amorphous zeolite-anchored Pd nanoparticles and the commercial Lindlar catalyst have styrene selectivities of 73 % and 15 %, respectively, under identical reaction conditions. This work establishes a solid foundation for developing highly active and selective hydrogenation catalysts by controllably optimizing their electronic and steric properties.

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