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1.
Proc Natl Acad Sci U S A ; 120(10): e2120536120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848565

RESUMO

During mitosis, cells round up and utilize the interphase adhesion sites within the fibrous extracellular matrix (ECM) as guidance cues to orient the mitotic spindles. Here, using suspended ECM-mimicking nanofiber networks, we explore mitotic outcomes and error distribution for various interphase cell shapes. Elongated cells attached to single fibers through two focal adhesion clusters (FACs) at their extremities result in perfect spherical mitotic cell bodies that undergo significant 3-dimensional (3D) displacement while being held by retraction fibers (RFs). Increasing the number of parallel fibers increases FACs and retraction fiber-driven stability, leading to reduced 3D cell body movement, metaphase plate rotations, increased interkinetochore distances, and significantly faster division times. Interestingly, interphase kite shapes on a crosshatch pattern of four fibers undergo mitosis resembling single-fiber outcomes due to rounded bodies being primarily held in position by RFs from two perpendicular suspended fibers. We develop a cortex-astral microtubule analytical model to capture the retraction fiber dependence of the metaphase plate rotations. We observe that reduced orientational stability, on single fibers, results in increased monopolar mitotic defects, while multipolar defects become dominant as the number of adhered fibers increases. We use a stochastic Monte Carlo simulation of centrosome, chromosome, and membrane interactions to explain the relationship between the observed propensity of monopolar and multipolar defects and the geometry of RFs. Overall, we establish that while bipolar mitosis is robust in fibrous environments, the nature of division errors in fibrous microenvironments is governed by interphase cell shapes and adhesion geometries.


Assuntos
Divisão do Núcleo Celular , Mitose , Centrossomo , Aeronaves , Axônios
2.
Plant J ; 117(2): 498-515, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37856574

RESUMO

Salt glands are the unique epidermal structures present in recretohalophytes, plants that actively excrete excess Na+ by salt secretory structures to avoid salt damage. Here, we describe a transmembrane protein that localizes to the plasma membrane of the recretohalophyte Limonium bicolor. As virus-induced gene silencing of the corresponding gene LbRSG in L. bicolor decreased the number of salt glands, we named the gene Reduced Salt Gland. We detected LbRSG transcripts in salt glands by in situ hybridization and transient transformation. Overexpression and silencing of LbRSG in L. bicolor pointed to a positive role in salt gland development and salt secretion by interacting with Lb3G16832. Heterologous LbRSG expression in Arabidopsis enhanced salt tolerance during germination and the seedling stage by alleviating NaCl-induced ion stress and osmotic stress after replacing or deleting the (highly) negatively charged region of extramembranous loop. After screened by immunoprecipitation-mass spectrometry and verified using yeast two-hybrid, PGK1 and BGLU18 were proposed to interact with LbRSG to strengthen salt tolerance. Therefore, we identified (highly) negatively charged regions in the extramembrane loop that may play an essential role in salt tolerance, offering hints about LbRSG function and its potential to confer salt resistance.


Assuntos
Plumbaginaceae , Tolerância ao Sal , Animais , Tolerância ao Sal/genética , Plumbaginaceae/genética , Plumbaginaceae/metabolismo , Glândula de Sal , Plântula/genética , Germinação , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas
3.
Cell Mol Life Sci ; 81(1): 189, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38643448

RESUMO

Peritoneal metastasis, the third most common metastasis in colorectal cancer (CRC), has a poor prognosis for the rapid progression and limited therapeutic strategy. However, the molecular characteristics and pathogenesis of CRC peritoneal metastasis are poorly understood. Here, we aimed to elucidate the action and mechanism of adipose-derived stem cells (ADSCs), a prominent component of the peritoneal microenvironment, in CRC peritoneal metastasis formation. Database analysis indicated that ADSCs infiltration was increased in CRC peritoneal metastases, and high expression levels of ADSCs marker genes predicted a poor prognosis. Then we investigated the effect of ADSCs on CRC cells in vitro and in vivo. The results revealed that CRC cells co-cultured with ADSCs exhibited stronger metastatic property and anoikis resistance, and ADSCs boosted the intraperitoneal seeding of CRC cells. Furthermore, RNA sequencing was carried out to identify the key target gene, angiopoietin like 4 (ANGPTL4), which was upregulated in CRC specimens, especially in peritoneal metastases. Mechanistically, TGF-ß1 secreted by ADSCs activated SMAD3 in CRC cells, and chromatin immunoprecipitation assay showed that SMAD3 facilitated ANGPTL4 transcription by directly binding to ANGPTL4 promoter. The ANGPTL4 upregulation was essential for ADSCs to promote glycolysis and anoikis resistance in CRC. Importantly, simultaneously targeting TGF-ß signaling and ANGPTL4 efficiently reduced intraperitoneal seeding in vivo. In conclusion, this study indicates that tumor-infiltrating ADSCs promote glycolysis and anoikis resistance in CRC cells and ultimately facilitate peritoneal metastasis via the TGF-ß1/SMAD3/ANGPTL4 axis. The dual-targeting of TGF-ß signaling and ANGPTL4 may be a feasible therapeutic strategy for CRC peritoneal metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Peritoneais , Humanos , Neoplasias Peritoneais/genética , Fator de Crescimento Transformador beta1 , Glicólise , Neoplasias Colorretais/genética , Células-Tronco , Microambiente Tumoral , Proteína Smad3/genética , Proteína 4 Semelhante a Angiopoietina/genética
4.
Antimicrob Agents Chemother ; 68(4): e0135023, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38470034

RESUMO

Influenza remains a significant threat to public health. In severe cases, excessive inflammation can lead to severe pneumonia or acute respiratory distress syndrome, contributing to patient morbidity and mortality. While antivirals can be effective if administered early, current anti-inflammatory drugs have limited success in treating severe cases. Therefore, discovering new anti-inflammatory agents to inhibit influenza-related inflammatory diseases is crucial. Herein, we screened a drug library with known targets using a human monocyte U937 infected with the influenza virus to identify novel anti-inflammatory agents. We also evaluated the anti-inflammatory effects of the hit compounds in an influenza mouse model. Our research revealed that JAK inhibitors exhibited a higher hit rate and more potent inhibition effect than inhibitors targeting other drug targets in vitro. Of the 22 JAK inhibitors tested, 15 exhibited robust anti-inflammatory activity against influenza virus infection in vitro. Subsequently, we evaluated the efficacy of 10 JAK inhibitors using an influenza mouse model and observed that seven provided protection ranging from 40% to 70% against lethal influenza virus infection. We selected oclacitinib as a representative compound for an extensive study to further investigate the in vivo therapeutic potential of JAK inhibitors for severe influenza-associated inflammation. Our results revealed that oclacitinib effectively suppressed neutrophil and macrophage infiltration, reduced pro-inflammatory cytokine production, and ultimately mitigated lung injury in mice infected with lethal influenza virus without impacting viral titer. These findings suggest that JAK inhibitors can modulate immune responses to influenza virus infection and may serve as potential treatments for influenza.IMPORTANCEAntivirals exhibit limited efficacy in treating severe influenza when not administered promptly during the infection. Current steroidal and nonsteroidal anti-inflammatory drugs demonstrate restricted effectiveness against severe influenza or are associated with significant side effects. Therefore, there is an urgent need for novel anti-inflammatory agents that possess high potency and minimal adverse reactions. In this study, 15 JAK inhibitors were identified through a screening process based on their anti-inflammatory activity against influenza virus infection in vitro. Remarkably, 7 of the 10 selected inhibitors exhibited protective effects against lethal influenza virus infection in mice, thereby highlighting the potential therapeutic value of JAK inhibitors for treating influenza.


Assuntos
Doenças Transmissíveis , Influenza Humana , Inibidores de Janus Quinases , Infecções por Orthomyxoviridae , Orthomyxoviridae , Pirimidinas , Sulfonamidas , Humanos , Animais , Camundongos , Influenza Humana/tratamento farmacológico , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/uso terapêutico , Citocinas , Infecções por Orthomyxoviridae/tratamento farmacológico , Inflamação/tratamento farmacológico , Doenças Transmissíveis/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Modelos Animais de Doenças , Antivirais/uso terapêutico , Antivirais/farmacologia , Pulmão
5.
BMC Plant Biol ; 24(1): 96, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331783

RESUMO

Eucalyptus was one of the most cultivated hardwood species worldwide, with rapid growth, good wood properties and a wide range of adaptability. Eucalyptus stem undergoes primary growth (longitudinal growth) followed by secondary growth (radial growth), which produces biomass that is an important source of energy worldwide. In order to better understand the genetic regulation of secondary growth in Eucalyptus grandis, Transcriptome analyses in stem segments along a developmental gradient from the third internode to the eleventh internode of E. grandis that spanned primary to secondary growth were carried out. 5,149 genes that were differentially expressed during stem development were identified. Combining the trend analysis by the Mfuzz method and the module-trait correlation analysis by the Weighted Gene Co-expression Network Analysis method, a total of 70 differentially expressed genes (DEGs) selected from 868 DEGs with high connectivity were found to be closely correlated with secondary growth. Results revealed that the differential expression of these DEGs suggests that they may involve in the primary growth or secondary growth. AP1, YAB2 TFs and EXP genes are highly expressed in the IN3, whereas NAC, MYB TFs are likely to be important for secondary growth. These results will expand our understanding of the complex molecular and cellular events of secondary growth and provide a foundation for future studies on wood formation in Eucalyptus.


Assuntos
Eucalyptus , Transcriptoma , Eucalyptus/genética , Eucalyptus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Madeira/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Bull World Health Organ ; 102(4): 276-287, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38562199

RESUMO

Objective: To quantify the association between reduction in child mortality and routine immunization across 204 countries and territories from 1990 to 2019. Methods: We used child mortality and vaccine coverage data from the Global Burden of Disease Study. We used a modified child survival framework and applied a mixed-effects regression model to estimate the reduction in deaths in children younger than 5 years associated with eight vaccines. Findings: Between 1990 and 2019, the diphtheria-tetanus-pertussis (DTP), measles, rotavirus and Haemophilus influenzae type b vaccines were significantly associated with an estimated 86.9 (95% confidence interval, CI: 57.2 to 132.4) million fewer deaths in children younger than 5 years worldwide. This decrease represented a 24.2% (95% CI: 19.8 to 28.9) reduction in deaths relative to a scenario without vaccines. The DTP and measles vaccines averted 46.7 (95% CI: 30.0 to 72.7) million and 37.9 (95% CI: 25.4 to 56.8) million deaths, respectively. Of the total reduction in child mortality associated with vaccines, 84.2% (95% CI: 83.0 to 85.1) occurred in 73 countries supported by Gavi, the Vaccine Alliance, with an estimated 45.4 (95% CI: 29.8 to 69.2) million fewer deaths from 2000 to 2019. The largest reductions in deaths associated with these four vaccines were in India, China, Ethiopia, Pakistan and Bangladesh (in order of the size of reduction). Conclusion: Vaccines continue to reduce childhood mortality significantly, especially in Gavi-supported countries, emphasizing the need for increased investment in routine immunization programmes.


Assuntos
Sarampo , Coqueluche , Criança , Humanos , Lactente , Programas de Imunização , Vacinação , Vacina contra Sarampo/uso terapêutico , Mortalidade da Criança , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacina contra Difteria, Tétano e Coqueluche
7.
Diabetes Obes Metab ; 26(2): 663-672, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38073424

RESUMO

AIM: To develop a visual prediction model for gestational diabetes (GD) in pregnant women and to establish an effective and practical tool for clinical application. METHODS: To establish a prediction model, the modelling set included 1756 women enrolled in the Zunyi birth cohort, the internal validation set included 1234 enrolled women, and pregnant women in the Wuhan cohort were included in the external validation set. We established a demographic-lifestyle factor model (DLFM) and a demographic-lifestyle-environmental pollution factor model (DLEFM) based on whether the women were exposed to environmental pollutants. The least absolute shrinkage and selection lasso-logistic regression analyses were used to identify the independent predictors of GD and construct a nomogram for predicting its occurrence. RESULTS: The DLEFM regression analysis showed that a family history of diabetes (odd ratio [OR] 2.28; 95% confidence interval [CI] 1.05-4.71), a history of GD in pregnant women (OR 4.22; 95% CI 1.89-9.41), being overweight or obese before pregnancy (OR 1.71; 95% CI 1.27-2.29), a history of hypertension (OR 2.61; 95% CI 1.41-4.72), sedentary time (h/day) (OR 1.16; 95% CI 1.08-1.24), monobenzyl phthalate (OR 1.95; 95% CI 1.45-2.67) and Q4 mono-ethyl phthalate concentration (OR 1.85; 95% CI 1.26-2.73) were independent predictors. The area under the receiver operating curves for the internal validation of the DLEFM and the DLFM constructed using these seven factors was 0.827 and 0.783, respectively. The calibration curve of the DLEFM was close to the diagonal line. The DLEFM was thus the more optimal model, and the one which we chose. CONCLUSIONS: A nomogram based on preconception factors was constructed to predict the occurrence of GD in the second and third trimesters. It provided an effective tool for the early prediction and timely management of GD.


Assuntos
Diabetes Gestacional , Ácidos Ftálicos , Gravidez , Feminino , Humanos , Diabetes Gestacional/epidemiologia , Estilo de Vida , Calibragem
8.
Environ Sci Technol ; 58(1): 603-616, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38109294

RESUMO

The mechanisms of the P. oxalicum SL2-mediated microbial community on phosphorus solubilization and Pb stabilization were investigated through a 90-day soil experiment. In the treatments inoculated with P. oxalicum SL2, the amount of P. oxalicum SL2-GFP remained at 77.8%-138.6% of the initial inoculation amount after 90 days, and the available phosphorus (AP) content increased 21.7%-40.8% while EDTA-Pb decreased 29.9%-43.2% compared with CK treatment. SEM-EDS results showed that P. oxalicum SL2 changed the agglomeration degree of microaggregates and promoted the combination of Pb with C and O elements. These phenomena were enhanced when applied with Ca3(PO4)2. Microbial community analysis showed that P. oxalicum SL2 improved soil microbial activity, in which the fungi absolute abundance increased about 15 times within 90 days. Correlation analyses and a partial least-squares path model showed that the activation of Penicillium, Ascobolus, Humicola, and Spizellomyces in a fungal community increased the content of oxalate and AP, which directly decreased EDTA-Pb content, while the change of Bacillus, Ramlibacter, Gemmatimonas, and Candidatus Solibacter in the bacterial community regulated Fe/Mn/S/N cycle-related functions, thus promoting the conversion of Pb to oxidizable state. Our findings highlight that P. oxalicum SL2 enhanced the microbial-induced phosphate precipitation process by activating soil microbial communities and regulating their ecological functions.


Assuntos
Penicillium , Fósforo , Chumbo , Solo , Ácido Edético
9.
Phys Chem Chem Phys ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980004

RESUMO

As an emerging two-dimensional material, MXene has shown a wide range of applications, which has triggered the demand for efficient exfoliation of nanoflakes with large size and specific surface area. Here, we took advantage of the efficient photo-thermal conversion of Ti3C2Tx and employed 532 nm continuous wave laser irradiation to assist the traditional ultrasonic exfoliation, with no need for complex equipment and an expensive femtosecond or picosecond laser. This approach greatly improves the exfoliation efficiency, increases the size, uniformity and specific surface area of the Ti3C2Tx nanoflakes, and reduces energy consumption as well. The electrical conductivity of Ti3C2Tx film is also significantly enhanced (from 3135 to 7433 S m-1). It is demonstrated that the laser promotes the formation of Ti-OH and enhances the solubility of Ti3C2Tx in water, facilitating the exfoliation and preventing oxidation as a result.

10.
Nature ; 553(7686): 106-110, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29300013

RESUMO

Class B G-protein-coupled receptors (GPCRs), which consist of an extracellular domain (ECD) and a transmembrane domain (TMD), respond to secretin peptides to play a key part in hormonal homeostasis, and are important therapeutic targets for a variety of diseases. Previous work has suggested that peptide ligands bind to class B GPCRs according to a two-domain binding model, in which the C-terminal region of the peptide targets the ECD and the N-terminal region of the peptide binds to the TMD binding pocket. Recently, three structures of class B GPCRs in complex with peptide ligands have been solved. These structures provide essential insights into peptide ligand recognition by class B GPCRs. However, owing to resolution limitations, the specific molecular interactions for peptide binding to class B GPCRs remain ambiguous. Moreover, these previously solved structures have different ECD conformations relative to the TMD, which introduces questions regarding inter-domain conformational flexibility and the changes required for receptor activation. Here we report the 3.0 Å-resolution crystal structure of the full-length human glucagon receptor (GCGR) in complex with a glucagon analogue and partial agonist, NNC1702. This structure provides molecular details of the interactions between GCGR and the peptide ligand. It reveals a marked change in the relative orientation between the ECD and TMD of GCGR compared to the previously solved structure of the inactive GCGR-NNC0640-mAb1 complex. Notably, the stalk region and the first extracellular loop undergo major conformational changes in secondary structure during peptide binding, forming key interactions with the peptide. We further propose a dual-binding-site trigger model for GCGR activation-which requires conformational changes of the stalk, first extracellular loop and TMD-that extends our understanding of the previously established two-domain peptide-binding model of class B GPCRs.


Assuntos
Glucagon/análogos & derivados , Receptores de Glucagon/química , Receptores de Glucagon/metabolismo , Cristalografia por Raios X , Agonismo Parcial de Drogas , Humanos , Ligantes , Modelos Moleculares , Ligação Proteica , Conformação Proteica
11.
Chem Biodivers ; 21(2): e202301781, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38146649

RESUMO

Polysaccharide from Asarum sieboldii Miq (ASP) was extracted and five phosphorylation polysaccharides with different degree of substitution were obtained, namely ASPP1, ASPP2, ASPP3, ASPP4, and ASPP5 (ASPPs). The physical and chemical structure and biological activities were studied. The results suggested that the carbohydrate and protein content were reduced while uronic acid was increased after phosphorylation modification. The molecular weight of ASPPs was significantly lower than that of ASP. ASPPs were acidic heteropolysaccharides mainly composed of galacturonic acid, galactose, glucose, fructose, and arabinose. The UV-vis spectrum indicated that the polysaccharides did not contain nucleic acid or protein after modification. The Fourier transform infrared spectrum demonstrated that ASPPs contained characteristic absorption peaks of P=O and P-O-C near 1270 and 980 cm-1 . ASPPs presented a triple helix conformation, but it was not presented in ASP. The scanning electron microscopy analysis showed that the surface topography and particle structure of ASP were different after modification. Compared with ASP, ASPPs enhanced the activity to scavenge DPPH and ABTS free radicals and possessed more protective ability to DNA oxidation caused by OH⋅, GS⋅, and AAPH free radicals. These results suggest that chemical modification is beneficial for the exploitation and utilization of natural polysaccharides.


Assuntos
Antioxidantes , Asarum , Antioxidantes/farmacologia , Antioxidantes/química , Fosforilação , Polissacarídeos/farmacologia , Polissacarídeos/química , Radicais Livres , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Commun Math Phys ; 405(4): 95, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606337

RESUMO

We extend three related results from the analysis of influences of Boolean functions to the quantum setting, namely the KKL theorem, Friedgut's Junta theorem and Talagrand's variance inequality for geometric influences. Our results are derived by a joint use of recently studied hypercontractivity and gradient estimates. These generic tools also allow us to derive generalizations of these results in a general von Neumann algebraic setting beyond the case of the quantum hypercube, including examples in infinite dimensions relevant to quantum information theory such as continuous variables quantum systems. Finally, we comment on the implications of our results as regards to noncommutative extensions of isoperimetric type inequalities, quantum circuit complexity lower bounds and the learnability of quantum observables.

13.
Environ Geochem Health ; 46(2): 53, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245580

RESUMO

The historical large mercury slag piles still contain high concentrations of mercury and their impact on the surrounding environment has rarely been reported. In this study, three different agricultural areas [the area with untreated piles (PUT), the area with treated piles (PT), and the background area with no piles (NP)] were selected to investigate mercury slag piles pollution in the Tongren mercury mining area. The mercury concentrations of agricultural soils ranged from 0.42 to 155.00 mg/kg, determined by atomic fluorescence spectrometry of 146 soil samples; and mercury concentrations in local crops (rice, maize, pepper, eggplant, tomato and bean) all exceeded the Chinese food safety limits. Soil and crop pollution trends in the three areas were consistent as PUT > PT > NP, indicating that mercury slag piles have exacerbated pollution. Mercury in the slag piles was adsorbed by multiple pathways of transport into soils with high organic matter, which made the ecological risk of agricultural soils appear extremely high. The total hazard quotients for residents from ingesting mercury in these crops were unacceptable in all areas, and children were more likely to be harmed than adults. Compared to the PT area, treatment of slag piles in the PUT area may decrease mercury concentrations in paddy fields and dry fields by 46.02% and 70.36%; further decreasing health risks for adults and children by 47.06% and 79.90%. This study provided a scientific basis for the necessity of treating large slag piles in mercury mining areas.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Mercúrio/toxicidade , Mercúrio/análise , Solo , Monitoramento Ambiental/métodos , Produtos Agrícolas/química , China , Mineração , Poluentes do Solo/análise , Medição de Risco , Metais Pesados/análise
14.
Mol Pharm ; 20(6): 2978-2990, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37115233

RESUMO

Under physiological conditions, nanoparticles (NPs) inevitably interact with proteins, resulting in extensive protein adsorption and the formation of a protein corona. Recent studies have shown that the different surface properties of NPs lead to varying degrees of conformational changes of adsorbed proteins. However, the impact of corona protein conformation on the in vitro and in vivo profiles of NPs remain largely unexplored. Herein, d-α-tocopherol polyethylene glycol 1000 succinate-based NPs with natural human serum albumin (HSAN) corona or thermally denatured HSA (HSAD) corona were synthesized following a previously established method. We then conducted a systematic study of the protein conformation as well as adsorption behaviors. Additionally, the impact of protein corona conformation on the NPs profiles in vitro and in vivo were elucidated to gain insight into its biological behaviors as a targeted delivery system for renal tubule diseases. Overall, NPs modified by HSAN corona showed improved serum stability, greater cell uptake efficiency, better renal tubular targetability, and therapeutic efficacy on acute kidney injury in rats than NPs modified by HSAD corona. Hence, the conformation of protein adsorbed on the surface of NPs may impact the in vitro and in vivo profiles of NPs.


Assuntos
Nanopartículas , Coroa de Proteína , Humanos , Ratos , Animais , Albuminas , Proteínas , Nanopartículas/metabolismo , Conformação Proteica
15.
J Endovasc Ther ; 30(5): 792-797, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36927122

RESUMO

PURPOSE: Vascular injury resulting from transpedicular bone grafting in the treatment of thoracolumbar burst fractures has not been reported but can be lethal. The management of patients with iatrogenic aortic injury remains a difficult clinical problem. This study describes a case of iatrogenic abdominal aortic rupture at the level of L2 during transpedicular bone grafting for the first time. CASE REPORT: A 55 year-old male patient suffered from a T12 vertebral body mild compression fracture and an L2 vertebral body burst fracture due to falling. This patient was treated with posterior open reduction and pedicle screw fixation combined with transpedicular bone grafting in the L2 vertebrae using a paravertebral approach. Unfortunately, during transpedicular bone grafting, the abdominal aorta was punctured by the tip of the graft funnel. The use of endovascular stent implantation successfully averted a clinical catastrophe. The patient had a good clinical outcome, and no complications associated with vascular trauma were apparent at a 1-year follow-up examination. CONCLUSION: For the repair of vascular injury caused by transpedicular bone grafting, endovascular techniques can provide a safe, minimally invasive, and effective treatment option. CLINICAL IMPACT: Surgeons should carefully evaluate the specificity of the patient's anatomical structures preoperatively and be more cautious during transpedicular bone grafting in the treatment of thoracolumbar burst fractures.


Assuntos
Ruptura Aórtica , Fraturas da Coluna Vertebral , Lesões do Sistema Vascular , Masculino , Humanos , Pessoa de Meia-Idade , Transplante Ósseo/métodos , Fixação Interna de Fraturas/métodos , Ruptura Aórtica/diagnóstico por imagem , Ruptura Aórtica/etiologia , Ruptura Aórtica/cirurgia , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/etiologia , Lesões do Sistema Vascular/cirurgia , Resultado do Tratamento , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/lesões , Vértebras Torácicas/cirurgia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Vértebras Lombares/cirurgia , Doença Iatrogênica , Stents
16.
Pharm Res ; 40(7): 1821-1833, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37291463

RESUMO

PURPOSE: Cerebral ischemia-reperfusion (I/R) injury remains a leading cause of mobility and mortality among patients with ischemic stroke. This study aims to develop a human serum albumin (HSA)-enriched nanoparticle platform for solubilizing clopidogrel bisulfate (CLP) for intravenous administration, and to explore the protective effect of HSA-enriched nanoparticles loaded with CLP (CLP-ANPs) against cerebral I/R injury in transient middle cerebral artery occlusion (MCAO) rat model. METHODS: CLP-ANPs were synthesized via a modified nanoparticle albumin-bound technology, lyophilized, and then characterized by morphology, particle size, zeta potential, drug loading capacity, encapsulation efficiency, stability and in vitro release kinetics. In vivo pharmacokinetic studies were conducted using Sprague-Dawley (SD) rats. Also, an MCAO rat model was established to explore the therapeutic effect of CLP-ANPs on cerebral I/R injury. RESULTS: CLP-ANPs remained spherical particles with a layer of proteins forming protein corona. Lyophilized CLP-ANPs after dispersion displayed an average size of about 235.6 ± 6.6 nm (PDI = 0.16 ± 0.08) with a zeta potential of about - 13.5 ± 1.8 mV. CLP-ANPs achieved sustained release for up to 168 h in vitro. Next, a single injection of CLP-ANPs dose-dependently reversed the histopathological changes induced by cerebral I/R injury possibly via attenuating apoptosis and reducing oxidative damages in the brain tissues. CONCLUSIONS: CLP-ANPs represent a promising and translatable platform system for the management of cerebral I/R injury during ischemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Nanopartículas , Traumatismo por Reperfusão , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Clopidogrel/uso terapêutico , Albumina Sérica Humana , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo
17.
Occup Environ Med ; 80(1): 34-41, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36424171

RESUMO

OBJECTIVE: Our aim was to elucidate the polycyclic aromatic hydrocarbon (PAH) metabolites exposure levels of pregnant women in the underdeveloped region of Zunyi, southwest China. METHODS: Sociodemographic information was collected via questionnaires, and urine samples were collected at the same time. A total of 3047 pregnant women participated in the study. Gas chromatography/mass spectrometry was used to detect the urine concentrations of 10 PAH metabolites. A generalised linear model (GLM) was used to identify predictive factors of PAH metabolites. RESULTS: All PAH metabolites had a detection rate greater than 60% (67.21%-90.57%) except for 4-OH-PHE at 55.54%. The median concentrations were 0.02-0.11 µg/g Cre except for 1-OH-NAP, 2-OH-NAP, 2-OH-FLU and 9-OH-FLU (0.36-0.50 µg/g Cre). The cluster analysis identified the phenanthrene and fluorene metabolite clusters (containing no other metabolites), while naphthalene metabolites (1-OH-NAP, 2-OH-NAP) could not be clustered without other metabolites. GLM analysis identified that pregnant women with the following characteristics have high urinary concentration of PAH metabolites: overweight, in the last trimester of pregnancy, distance between their house and main traffic lines as <5 m, use fuel for cooking, passive smoking, renovated their residence for less than 3 years, middle family income and office workers. CONCLUSION: The results clarified pregnant women from the economically underdeveloped area could be the victims of PAHs. In addition, PAHs present a demographic and seasonal differential distribution, which will aid in the development of targeted interventions and reduce exposure to PAHs during pregnancy.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Feminino , Humanos , Gravidez , Gestantes , Monitoramento Ambiental/métodos , Biomarcadores/urina , China
18.
Bioorg Chem ; 138: 106604, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37178648

RESUMO

Traditional Chinese medicine is the main source of natural products due to its remarkable clinical efficacy. Syringa oblata Lindl (S. oblata) was widely used because of its extensive biological activities. However, to explore the antioxidant components of S. oblata against tyrosinase, the experiments of antioxidation in vitro were employed. At the same time, the determination of TPC was also use to assess the antioxidant ability of CE, MC, EA and WA fractions and the liver protective activity of the EA fraction was evaluated by mice in vivo. Next, UF-LC-MS technology was performed to screen and identify the efficient tyrosinase inhibitors in S. oblata. The results showed that alashinol (G), dihydrocubebin, syripinin E and secoisolariciresinol were characterized as potential tyrosinase ligands and their RBA values were 2.35, 1.97, 1.91 and 1.61, respectively. Moreover, these four ligands can effectively dock with tyrosinase molecules, with binding energies (BEs) ranging from 0.74 to -0.73 kcal/mol. In addition, tyrosinase inhibition experiment was employed to evaluate the tyrosinase inhibition activities of four potential ligands, the result showed that compound 12 (alashinol G, IC50 = 0.91 ± 0.20 mM) showed the strongest activity to tyrosinase, followed by secoisolariciresinol (IC50 = 0.99 ± 0.07 mM), dihydrocubebin (IC50 = 1.04 ± 0.30 mM) and syripinin E (IC50 = 1.28 ± 0.23 mM), respectively. The results demonstrate that S. oblata might have excellent antioxidant activity, and UF-LC-MS technique is a effective means to filter out tyrosinase inhibitors from natural products.


Assuntos
Antioxidantes , Syringa , Animais , Camundongos , Antioxidantes/farmacologia , Monofenol Mono-Oxigenase , Ultrafiltração/métodos , Ligantes , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química
19.
Nature ; 546(7657): 259-264, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28514451

RESUMO

The human glucagon receptor, GCGR, belongs to the class B G-protein-coupled receptor family and plays a key role in glucose homeostasis and the pathophysiology of type 2 diabetes. Here we report the 3.0 Å crystal structure of full-length GCGR containing both the extracellular domain and transmembrane domain in an inactive conformation. The two domains are connected by a 12-residue segment termed the stalk, which adopts a ß-strand conformation, instead of forming an α-helix as observed in the previously solved structure of the GCGR transmembrane domain. The first extracellular loop exhibits a ß-hairpin conformation and interacts with the stalk to form a compact ß-sheet structure. Hydrogen-deuterium exchange, disulfide crosslinking and molecular dynamics studies suggest that the stalk and the first extracellular loop have critical roles in modulating peptide ligand binding and receptor activation. These insights into the full-length GCGR structure deepen our understanding of the signalling mechanisms of class B G-protein-coupled receptors.


Assuntos
Receptores de Glucagon/química , Receptores de Glucagon/classificação , Sítio Alostérico/efeitos dos fármacos , Benzamidas/química , Benzamidas/metabolismo , Benzamidas/farmacologia , Membrana Celular/metabolismo , Reagentes de Ligações Cruzadas/química , Cristalografia por Raios X , Medição da Troca de Deutério , Dissulfetos/química , Humanos , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Compostos de Fenilureia/química , Compostos de Fenilureia/metabolismo , Compostos de Fenilureia/farmacologia , Domínios Proteicos , Estabilidade Proteica , Receptores de Glucagon/agonistas , Receptores de Glucagon/metabolismo
20.
J Enzyme Inhib Med Chem ; 38(1): 2202362, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37080774

RESUMO

A series of 21 novel compounds containing a thiosemicarbazone moiety were designed and synthesised based on hit compound 1 from our in-house compound library screening. Most compounds showed potent antifungal activity in vitro against seven common pathogenic fungi. Notably, all compounds showed high potency against Candida glabrata 537 (MIC = ≤0.0156-2 µg/mL). Of note, compounds 5j and 5r displayed excellent antifungal activity against Candida krusei 4946 and Candida auris 922. Additionally, compounds 5j and 5r also showed high potency against 15 C. glabrata isolates with MIC values ranging from 0.0625 µg/mL to 4 µg/mL, with compound 5r being slightly superior to 5j. Moreover, compound 5r has certain effect against biofilm formation of C. glabrata. Furthermore, compound 5r has minimal cytotoxicity against HUVECs with an IC50 value of 15.89 µg/mL and no haemolysis at 64 µg/mL. Taken together, these results suggest that promising lead compound 5r deserves further investigation.


Assuntos
Antifúngicos , Candida glabrata , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Fungos
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