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1.
Infect Drug Resist ; 17: 1185-1198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560706

RESUMO

Background and Aim: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a complicated syndrome with high short-term mortality. Effective biomarkers are required for its early diagnosis and prognosis. This study aimed to determine the diagnostic and prognostic value of thrombomodulin (TM) in patients with HBV-ACLF. Methods: The expression of TM during disease progression was evaluated through transcriptomics analysis. The plasma TM concentrations of 393 subjects with HBV-ACLF (n=213), acute-on-chronic hepatic dysfunction (ACHD, n=50), liver cirrhosis (LC, n=50) or chronic hepatitis B (CHB, n=50), and normal controls (NC, n=30) from a prospective multicenter cohort, were measured to verify the diagnostic and prognostic significance of plasma TM for HBV-ACLF patients by enzyme-linked immunosorbent assay (ELISA). Results: TM mRNA was highly expressed in the HBV-ACLF group compared with the ACHD group (AUROC=0.710). High expression of TM predicted poor prognosis for HBV-ACLF patients at 28/90 days (AUROCs=0.823/0.788). Functional analysis showed that TM was significantly associated with complement activation and the inflammatory signaling pathway. External validation confirmed its high diagnostic accuracy for HBV-ACLF patients (AUROC=0.796). Plasma TM concentrations were correlated with organ failure, including coagulation and kidney failure. Plasma TM concentrations showed a potential prognostic value for 28-day mortality rates (AUROC=0.702). Risk stratification specifically identified HBV-ACLF patients with a high risk of death as having a plasma TM concentration of ≥8.4 ng/mL. Conclusion: This study reveals that the plasma TM can be a candidate biomarker for early diagnosis and prognosis of HBV-ACLF, and might play a vital role in coagulation and inflammation.

2.
Eur J Radiol ; 173: 111363, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367415

RESUMO

PURPOSE: To assess diagnostic performance and reproducibility of reduced bowel wall enhancement evaluated by quantitative methods using CT to identify bowel necrosis among closed-loop small bowel obstruction (CL-SBO) patients. METHODS: This retrospective single-center study included patients who diagnosed with CL-SBO caused by adhesion or internal hernia during January 2016 and May 2022. Patients were divided into necrotic group (n = 41) and non-necrotic group (n = 67) according to surgical exploration and postoperative pathology. Two doctors independently measured the attenuation of bowel wall and consensus was reached through panel discussion with a third gastrointestinal radiologist. Reduced bowel wall enhancement was assessed by four quantitative methods. Univariate analyses were used to evaluate the association between each method and bowel necrosis, and kappa/intraclass correlation coefficient values were used to assess interobserver agreement. Diagnostic performance parameters were calculated for each method. RESULTS: Reduced bowel wall enhancement in arterial phase (OR 8.98, P < 0.0001), reduced bowel wall enhancement in portal phase (OR 16.84, P < 0.001), adjusted reduced bowel wall enhancement in arterial phase (OR 29.48, P < 0.001), adjusted reduced bowel wall enhancement in portal phase (OR 145.69, P < 0.001) were significantly associated with bowel necrosis. Adjusted reduced bowel wall enhancement in portal phase had the best diagnostic performance (AUC: 0.92; Youden index: 0.84; specificity: 94.03 %) and interobserver agreement (kappa value of 0.59-0.73) to predict bowel necrosis. CONCLUSION: When assessing reduced bowel enhancement to predict bowel necrosis among CL-SBO patients, using unenhanced CT images and proximal dilated loop as standard references in portal phase is the most accurate quantitative method among those tested.


Assuntos
Traumatismos Abdominais , Obstrução Intestinal , Doenças Vasculares , Humanos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Intestino Delgado/diagnóstico por imagem , Sensibilidade e Especificidade , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/cirurgia , Doenças Vasculares/patologia , Necrose/diagnóstico por imagem , Necrose/patologia , Traumatismos Abdominais/complicações
3.
Radiology ; 310(2): e231710, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38319165

RESUMO

Background Preoperative recognition of irreversible bowel necrosis is important, as it provides valuable guidance for surgical strategy selection but also may inform perioperative risk assessment and communication. Few studies have focused on the association between CT signs and bowel necrosis. Purpose To assess the diagnostic accuracy of CT signs to predict bowel necrosis in patients with closed-loop small bowel obstruction (CL-SBO). Materials and Methods This retrospective single-center study included patients who were surgically confirmed to have CL-SBO caused by adhesion or internal hernia between January 2016 and May 2022. Necrosis was determined based on surgical exploration and postoperative pathologic examination. Two radiologists independently reviewed CT signs by both subjective visual assessment and objective measurement. Disagreements were resolved in consensus with a third gastrointestinal radiologist. Univariable and multivariable analyses were used to assess the association between CT signs and bowel necrosis, and Cohen κ was used to assess interobserver agreement. Sensitivity and specificity were calculated for each CT sign. Results This study included 145 patients: 61 (42.1%) in the necrotic group (median age, 62 years [IQR, 51-71.5 years]; 37 [60.7%] women) and 84 (57.9%) in the nonnecrotic group (median age, 61.5 years [IQR, 51-68.8 years]; 51 [60.7%] women). Univariable analysis and multivariable analysis showed that increased attenuation of intestinal contents and increased attenuation of intestinal wall were independent predictors for bowel necrosis (odds ratio = 45.3 and 15.1; P = .001 and P < .001, respectively). Increased attenuation of intestinal contents and increased attenuation of intestinal wall had similar sensitivity (64% and 67%, respectively) and specificity (99% and 92%, respectively) for predicting bowel necrosis. However, interobserver agreement was better for assessing the contents than the wall (κ = 0.84 and 0.59, respectively). Conclusion Increased attenuation of intestinal contents was a highly specific CT sign with good reproducibility to predict bowel necrosis in CL-SBO. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Taourel and Zins in this issue.


Assuntos
Conteúdo Gastrointestinal , Obstrução Intestinal , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/cirurgia , Necrose/diagnóstico por imagem , Tomografia Computadorizada por Raios X
4.
Autoimmunity ; 56(1): 2276066, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37994026

RESUMO

Circular RNAs (circRNAs) has been manifested to be involved in the development of human diseases, including sepsis-associated acute kidney injury (SA-AKI). However, the function and mechanism of circ_0006944 in SA-AKI has not been validated. Lipopolysaccharide (LPS) was utilised to induce AKI cell model. Levels of genes and proteins were monitored by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell counting kit 8 assay, EdU assay and flow cytometry were exploited to estimate cell proliferation and apoptosis. The concentrations of inflammation factors were measured via using ELISA assay. The levels of MDA and SOD were tested by the corresponding kits. The relationship between miR-205-5p and circ_0006944 or UBL4A was verified by dual-luciferase reporter assay and RIP assay. Circ_0006944 was overexpressed in SA-AKI patients, and interference of circ_0006944 restrained LPS-stimulated HK2 cell proliferation repression, apoptosis, inflammation and oxidative stress. Mechanistically, circ_0006944 could sponge miR-205-5p, and miR-205-5p interference counteracted circ_0006944 inhibition-mediated impact on the biological functions in LPS-induced HK2 cell. Additionally, UBL4A was targeted by miR-205-5p, and UBL4A overexpression also partially abolished the repressive impacts of miR-205-5p on LPS-triggered HK2 cell damage. Importantly, circ_0006944 sponged miR-205-5p to mediate the expression of UBL4A. Our outcomes identified that circ_0006944 exacerbated SA-AKI development via miR-205-5p/UBL4A axis, which might be a potential treatment and diagnosis biomarker for SA-AKI.


Assuntos
Injúria Renal Aguda , MicroRNAs , RNA Circular , Sepse , Ubiquitinas , RNA Circular/genética , MicroRNAs/genética , Ubiquitinas/genética , Sepse/complicações , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/genética , Humanos , Linhagem Celular , Inflamação , Estresse Oxidativo
5.
JHEP Rep ; 5(9): 100848, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37583946

RESUMO

Background & Aims: HBV-related acute-on-chronic liver failure (HBV-ACLF) is a complex syndrome associated with high short-term mortality. This study aims to reveal the molecular basis and identify novel HBV-ACLF biomarkers. Methods: Seventy patients with HBV-ACLF and different short-term (28 days) outcomes underwent transcriptome sequencing using peripheral blood mononuclear cells. Candidate biomarkers were confirmed in two external cohorts using ELISA. Results: Cellular composition analysis with peripheral blood mononuclear cell transcriptomics showed that the proportions of monocytes, T cells and natural killer cells were significantly correlated with 28-day mortality. Significant metabolic dysregulation of carbohydrate, energy and amino acid metabolism was observed in ACLF non-survivors. V-set and immunoglobulin domain-containing 4 (VSIG4) was the most robust predictor of patient survival (adjusted p = 1.74 × 10-16; variable importance in the projection = 1.21; AUROC = 0.89) and was significantly correlated with pathways involved in the progression of ACLF, including inflammation, oxidative phosphorylation, tricarboxylic acid cycle and T-cell activation/differentiation. Plasma VSIG4 analysis externally validated its diagnostic value in ACLF (compared with chronic liver disease and healthy groups, AUROC = 0.983). The prognostic performance for 28-/90-day mortality (AUROCs = 0.769/0.767) was comparable to that of three commonly used scores (COSSH-ACLFs, 0.867/0.884; CLIF-C ACLFs, 0.840/0.835; MELD-Na, 0.710/0.737). Plasma VSIG4 level, as an independent predictor, could be used to improve the prognostic performance of clinical scores. Risk stratification based on VSIG4 expression levels (>122 µg/ml) identified patients with ACLF at a high risk of death. The generality of VSIG4 in other etiologies was validated. Conclusions: This study reveals that immune-metabolism disorder underlies poor ACLF outcomes. VSIG4 may be helpful as a diagnostic and prognostic biomarker in clinical practice. Impact and implications: Acute-on-chronic liver failure (ACLF) is a lethal clinical syndrome associated with high mortality. We found significant immune cell alterations and metabolic dysregulation that were linked to high mortality in patients with HBV-ACLF based on transcriptomics using peripheral blood mononuclear cells. We identified VSIG4 (V-set and immunoglobulin domain-containing 4) as a diagnostic and prognostic biomarker in ACLF, which could specifically identify patients with ACLF at a high risk of death.

6.
ACS Omega ; 8(14): 13109-13117, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37065011

RESUMO

Cracking agents are indispensable and important products for national energy exploitation and large-scale infrastructure construction. Transient thermal expansion rock cracking agent is a new cracking agent product with excellent performance that has just appeared in recent years. However, it is still prepared by mechanical ball milling, which is considered not the best choice among traditional methods for preparing energetic materials. In this paper, a transient thermal expansion rock splitting agent was prepared by the chemical deposition method using carbon black and calcium peroxide as raw materials. The TG/DTG results show that the mass loss of the sample can be divided into four stages with the increase of temperature. It is worth noting that the mass loss of the TG curve of the sample during the entire thermal decomposition process is 93.385%, and the instantaneous weight loss is 78.07% (ß = 15 °C/min). Kinetic analysis of the thermal decomposition process of the samples was performed using an isotransformation program and a distributed activation energy model (DAEM). The activation energy E α of the thermal decomposition of the sample was iteratively calculated. The results show that the a-E a curve of the sample can be divided into two stages. The pyrolysis kinetics of the first stage was successfully analyzed by the DAEM method and its thermal conversion behavior was predicted. The thermal decomposition behavior of the second stage was analyzed by a traditional kinetic analysis method.

7.
J Med Virol ; 95(4): e28710, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36975761

RESUMO

Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a syndrome with high short-term mortality. The mechanism of the transcription factor ETS2 in ACLF remains unclear. This study aimed to clarify the molecular basis of ETS2 in ACLF pathogenesis. Peripheral blood mononuclear cells from patients with HBV-ACLF (n = 50) were subjected to RNA sequencing. Transcriptome analysis showed that ETS2 expression was significantly higher in ACLF patients than in patients with chronic liver diseases and healthy subjects (all p < 0.001). Area-under-ROC analysis of ETS2 demonstrated high values for the prediction of 28-/90-day mortality in ACLF patients (0.908/0.773). Significantly upregulated signatures of the innate immune response (monocytes/neutrophils/inflammation-related pathways) were observed in ACLF patients with high ETS2 expression. Myeloid-specific ETS2 deficiency in liver failure mice resulted in deterioration of biofunctions and increased expression of pro-inflammatory cytokines (IL-6/IL-1ß/TNF-α). Knockout of ETS2 in macrophages confirmed the downregulation of IL-6 and IL-1ß caused by both HMGB1 and lipopolysaccharide, and an NF-κB inhibitor reversed the suppressive effect of ETS2. ETS2 is a potential prognostic biomarker of ACLF patients that alleviates liver failure by downregulating the HMGB1-/lipopolysaccharide-triggered inflammatory response and may serve as a therapeutic target for ACLF.


Assuntos
Insuficiência Hepática Crônica Agudizada , Proteína HMGB1 , Hepatite B Crônica , Animais , Camundongos , Insuficiência Hepática Crônica Agudizada/patologia , Vírus da Hepatite B , Proteína HMGB1/metabolismo , Inflamação/metabolismo , Interleucina-6/genética , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos , Camundongos Knockout , Prognóstico , Humanos
8.
ACS Biomater Sci Eng ; 9(4): 1940-1951, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36913674

RESUMO

Functional bioengineered livers (FBLs) are promising alternatives to orthotopic liver transplantation. However, orthotopic transplantation of FBLs has not yet been reported. This study aimed to perform the orthotopic transplantation of FBLs in rats subjected to complete hepatectomy. FBLs were developed using rat whole decellularized liver scaffolds (DLSs) with human umbilical vein endothelial cells implanted via the portal vein, and human bone marrow mesenchymal stem cells (hBMSCs) and mouse hepatocyte cell line implanted via the bile duct. FBLs were evaluated in terms of endothelial barrier function, biosynthesis, and metabolism and orthotopically transplanted into rats to determine the survival benefit. The FBLs with well-organized vascular structures exhibited endothelial barrier function, with reduced blood cell leakage. The implanted hBMSCs and hepatocyte cell line were well aligned in the parenchyma of the FBLs. The high levels of urea, albumin, and glycogen in the FBLs indicated biosynthesis and metabolism. Orthotopic transplantation of FBLs achieved a survival time of 81.38 ± 4.263 min in rats (n = 8) subjected to complete hepatectomy, whereas control animals (n = 4) died within 30 min (p < 0.001). After transplantation, CD90-positive hBMSCs and the albumin-positive hepatocyte cell line were scattered throughout the parenchyma, and blood cells were limited within the vascular lumen of the FBLs. In contrast, the parenchyma and vessels were filled with blood cells in the control grafts. Thus, orthotopic transplantation of whole DLS-based FBLs can effectively prolong the survival of rats subjected to complete hepatectomy. In summary, this work was the first to perform the orthotopic transplantation of FBLs, with limited survival benefits, which still has important value for the advancement of bioengineered livers.


Assuntos
Transplante de Fígado , Fígado , Camundongos , Ratos , Animais , Humanos , Fígado/cirurgia , Fígado/fisiologia , Hepatócitos , Células Endoteliais da Veia Umbilical Humana , Albuminas
9.
Lancet Reg Health West Pac ; 32: 100638, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36793753

RESUMO

Background: Liver transplantation (LT) is an effective therapy for acute-on-chronic liver failure (ACLF) but is limited by organ shortages. We aimed to identify an appropriate score for predicting the survival benefit of LT in HBV-related ACLF patients. Methods: Hospitalized patients with acute deterioration of HBV-related chronic liver disease (n = 4577) from the Chinese Group on the Study of Severe Hepatitis B (COSSH) open cohort were enrolled to evaluate the performance of five commonly used scores for predicting the prognosis and transplant survival benefit. The survival benefit rate was calculated to reflect the extended rate of the expected lifetime with vs. without LT. Findings: In total, 368 HBV-ACLF patients received LT. They showed significantly higher 1-year survival than those on the waitlist in both the entire HBV-ACLF cohort (77.2%/52.3%, p < 0.001) and the propensity score matching cohort (77.2%/27.6%, p < 0.001). The area under the receiver operating characteristic curve (AUROC) showed that the COSSH-ACLF II score performed best (AUROC 0.849) at identifying the 1-year risk of death on the waitlist and best (AUROC 0.864) at predicting 1-year outcome post-LT (COSSH-ACLFs/CLIF-C ACLFs/MELDs/MELD-Nas: AUROC 0.835/0.825/0.796/0.781; all p < 0.05). The C-indexes confirmed the high predictive value of COSSH-ACLF IIs. Survival benefit rate analyses showed that patients with COSSH-ACLF IIs 7-10 had a higher 1-year survival benefit rate from LT (39.2%-64.3%) than those with score <7 or >10. These results were prospectively validated. Interpretation: COSSH-ACLF IIs identified the risk of death on the waitlist and accurately predicted post-LT mortality and survival benefit for HBV-ACLF. Patients with COSSH-ACLF IIs 7-10 derived a higher net survival benefit from LT. Funding: This study was supported by the National Natural Science Foundation of China (No. 81830073, No. 81771196) and the National Special Support Program for High-Level Personnel Recruitment (Ten-thousand Talents Program).

10.
Life Sci ; 317: 121438, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36709913

RESUMO

Acute-on-chronic liver failure (ACLF) is a syndrome characterized by acute decompensation of chronic liver disease associated with multiple-organ failures and high short-term mortality. Acute insults to patients with chronic liver disease can lead to ACLF, among which, hepatitis B virus-related ACLF is the most common type of liver failure in the Asia-Pacific region. Currently, immune-metabolism disorders and systemic inflammation are proposed to be the main mechanisms of ACLF. The resulting cholestasis and intrahepatic microcirculatory dysfunction accelerate the development of ACLF. Treatments targeting immune regulation, metabolic balance, microcirculation maintenance and bile duct repair can alleviate inflammation and restore the tissue structure. An increasing number of studies have demonstrated that delta-like ligand 4 (DLL4), one of the Notch signalling ligands, plays a vital role in immune regulation, metabolism, angiogenesis, and biliary regeneration, which participate in liver pathological and physiological processes. The detailed mechanism of the DLL4-Notch signalling pathway in ACLF has rarely been investigated. Here, we review the evidence showing that DLL4-Notch signalling is involved in ACLF and analyse the potential role of DLL4 in the treatment of ACLF.


Assuntos
Insuficiência Hepática Crônica Agudizada , Humanos , Insuficiência Hepática Crônica Agudizada/complicações , Insuficiência Hepática Crônica Agudizada/terapia , Cirrose Hepática/complicações , Microcirculação , Inflamação/complicações , Transdução de Sinais , Proteínas de Ligação ao Cálcio , Proteínas Adaptadoras de Transdução de Sinal
11.
Medicine (Baltimore) ; 101(35): e30210, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36107513

RESUMO

BACKGROUND: This study aimed to investigate the effects of sleep insufficiency on spatial working memory in low-pressure and hypoxic environments. METHODS: We selected 58 insufficient sleepers and 27 normal sleepers among the college students living in high-altitude areas for a long time to receive a spatial 2-back working memory task, while collecting behavioral and electroencephalograph data. We adopted an independent sample t-test and repeated measures analysis of variance to compare the differences in response time and accuracy, P2 and late positive potential components, and theta band energy values in the spatial working memory task between insufficient and normal sleepers. RESULTS: We found no significant differences in response time and accuracy between the insufficient sleep group and the normal sleep group; however, the P2 peak value and the early theta band energy value were higher in the insufficient sleep group than in the normal sleep group. CONCLUSIONS: These results suggest that the spatial working memory ability of individuals with sleep insufficiency was weakened under low-pressure and low-oxygen environment.


Assuntos
Memória de Curto Prazo , Privação do Sono , Humanos , Hipóxia/complicações , Memória de Curto Prazo/fisiologia , Oxigênio , Tempo de Reação/fisiologia
13.
Proc Natl Acad Sci U S A ; 119(11): e2123353119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35275795

RESUMO

SignificanceAlthough plastid division is critical for plant development, how components of the plastid division machinery (PDM) are imported into plastids remains unexplored. A forward genetic screen to identify suppressors of a crumpled leaf (crl) mutant deficient in plastid division led us to find dominant gain-of-function (GF) mutations in TIC236, which significantly increases the import of PDM components and completely rescues crl phenotypes. The defective plastid division phenotypes in crl and tic236-knockdown mutants and CRL-TIC236 association in a functional complex indicate that the CRL-TIC236 module is vital for plastid division. Hence, we report the first GF translocon mutants and unveil CRL as a novel functional partner of TIC236 for PDM import.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Divisão Celular , Proteínas de Cloroplastos , Proteínas de Membrana Transportadoras , Plastídeos , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , Mutação com Ganho de Função , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Plastídeos/genética , Plastídeos/metabolismo , Transporte Proteico
14.
Pancreas ; 51(10): 1263-1276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37099766

RESUMO

OBJECTIVES: The aims of this review were to determine whether positive peritoneal lavage cytology (CY+) precludes radical resection in pancreatic cancer and to propose prospections for future studies. METHODS: MEDLINE, Embase, and Cochrane Central were searched for related articles. Dichotomous variables and survival outcomes were analyzed with the estimation of odds ratio and hazards ratio (HR), respectively. RESULTS: A total of 4905 patients were included, of which 7.8% were CY+. Positive peritoneal lavage cytology was correlated with poor overall survival (univariate survival analysis [HR, 2.35; P < 0.00001]; multivariate analysis [HR, 1.62; P < 0.00001]), poor recurrence-free survival (univariate survival analysis [HR, 2.50; P < 0.00001]; multivariate analysis [HR, 1.84; P < 0.00001]), and higher initial peritoneal recurrence rate (odds ratio, 5.49; P < 0.00001). CONCLUSIONS: Although CY+ predicts poor prognosis and a higher risk of peritoneal metastasis after curative resection, it is not sufficient to preclude curative resection based on the current evidence, and high-quality trials should be conducted to assess the prognostic impact of operation among resectable CY+ patients. In addition, more sensitive and accurate methods to detect peritoneal exfoliated tumor cells and more effective comprehensive treatment for resectable CY+ pancreatic cancer patients are clearly warranted.


Assuntos
Neoplasias Pancreáticas , Neoplasias Peritoneais , Humanos , Citologia , Peritônio , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia , Lavagem Peritoneal/métodos , Neoplasias Peritoneais/secundário , Prognóstico , Estudos Retrospectivos , Neoplasias Pancreáticas
15.
Molecules ; 26(21)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34771043

RESUMO

Neural stem cells (NSCs) exist in the central nervous system of adult animals and capable of self-replication. NSCs have two basic functions, namely the proliferation ability and the potential for multi-directional differentiation. In this study, based on the bioassay-guided fractionation, we aim to screen active components in Cuscuta chinensis to promote the proliferation of NSCs. CCK-8 assays were used as an active detection method to track the active components. On the basis of isolating active fraction and monomer compounds, the structures of these were identified by LC-MS and (1H, 13C) NMR. Moreover, active components were verified by pharmacodynamics and network pharmacology. The system solvent extraction method combined with the traditional isolation method were used to ensure that the fraction TSZE-EA-G6 of Cuscuta chinensis exhibited the highest activity. Seven chemical components were identified from the TSZE-EA-G6 fraction by UPLC-QE-Orbitrap-MS technology, which were 4-O-p-coumarinic acid, chlorogenic acid, 5-O-p-coumarinic acid, hyperoside, astragalin, isochlorogenic acid C, and quercetin-3-O-galactose-7-O-glucoside. Using different chromatographic techniques, five compounds were isolated in TSZE-EA-G6 and identified as kaempferol, kaempferol-3-O-glucoside (astragalin), quercetin-3-O-galactoside (hyperoside), chlorogenic acid, and sucrose. The activity study of these five compounds showed that the proliferation rate of kaempferol had the highest effects; at a certain concentration (25 µg/mL, 3.12 µg/mL), the proliferation rate could reach 87.44% and 59.59%, respectively. Furthermore, research results using network pharmacology techniques verified that kaempferol had an activity of promoting NSCs proliferation and the activity of flavonoid aglycones might be greater than that of flavonoid glycosides. In conclusion, this research shows that kaempferol is the active component in Cuscuta chinensis to promote the proliferation of NSCs.


Assuntos
Cuscuta/química , Medicamentos de Ervas Chinesas/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Feminino , Espectrometria de Massas , Células-Tronco Neurais/citologia , Ratos
16.
Langmuir ; 37(23): 7219-7226, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34078082

RESUMO

In this work, lignin/chitosan nanoparticles (Lig/Chi NPs) with controlled structures were synthesized in a simple and scalable microfluidic system. When the positively charged chitosan and the negatively charged lignin solution were blended in a microreactor, Lig/Chi NPs were rapidly formed via the electrostatic coassembly between the amino groups of chitosan and the carboxyl groups of lignin. The ζ potential changes from negative (-13 mV) to positive (+54.5 mV) for Lig NPs and Lig/Chi NPs, respectively. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results demonstrated that Lig/Chi NPs have an average particle size of about 180 nm, which can be used as nanocarriers for drug delivery. The anticancer drug nanoparticles with docetaxel (DTX) and curcumin (CCM) were prepared by coassembly with Lig/Chi NPs in a microreactor, which had good drug loading efficiency, biocompatibility, and can release drugs in response to pH in the weakly acidic environment of the tumor. The drug release amounts in acidic solutions that simulated the tumor microenvironment were 51% (DTX@Lig/Chi NPs) and 50% (CCM@Lig/Chi NPs), respectively, which were better than the release amounts at pH 7.4, and have an obvious killing effect on HeLa cells.


Assuntos
Antineoplásicos , Quitosana , Nanopartículas , Antineoplásicos/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Lignina , Microfluídica , Tamanho da Partícula
17.
Plant Cell ; 32(10): 3240-3255, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32796124

RESUMO

Chloroplasts mediate genetically controlled cell death via chloroplast-to-nucleus retrograde signaling. To decipher the mechanism, we examined chloroplast-linked lesion-mimic mutants of Arabidopsis (Arabidopsis thaliana) deficient in plastid division, thereby developing gigantic chloroplasts (GCs). These GC mutants, including crumpled leaf (crl), constitutively express immune-related genes and show light-dependent localized cell death (LCD), mirroring typical autoimmune responses. Our reverse genetic approach excludes any potential role of immune/stress hormones in triggering LCD. Instead, transcriptome and in silico analyses suggest that reactive electrophile species (RES) generated via oxidation of polyunsaturated fatty acids (PUFAs) or lipid peroxidation-driven signaling may induce LCD. Consistent with these results, the one of the suppressors of crl, dubbed spcrl4, contains a causative mutation in the nuclear gene encoding chloroplast-localized FATTY ACID DESATURASE5 (FAD5) that catalyzes the conversion of palmitic acid (16:0) to palmitoleic acid (16:1). The loss of FAD5 in the crl mutant might attenuate the levels of RES and/or lipid peroxidation due to the reduced levels of palmitic acid-driven PUFAs, which are prime targets of reactive oxygen species. The fact that fad5 also compromises the expression of immune-related genes and the development of LCD in other GC mutants substantiates the presence of an intrinsic retrograde signaling pathway, priming the autoimmune responses in a FAD5-dependent manner.


Assuntos
Proteínas de Arabidopsis/imunologia , Arabidopsis/imunologia , Cloroplastos/imunologia , Ácidos Graxos Dessaturases/imunologia , Imunidade Vegetal/fisiologia , Arabidopsis/citologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Morte Celular/genética , Cloroplastos/genética , Ciclopentanos/metabolismo , Ácidos Graxos Dessaturases/genética , Regulação da Expressão Gênica de Plantas , Genes de Cloroplastos , Mutação , Oxilipinas/metabolismo , Ácido Palmítico/metabolismo , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Plastídeos/genética , Ácido Salicílico/metabolismo
18.
Plant J ; 104(4): 964-978, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32860438

RESUMO

The photosynthetic bacterial phycobiliprotein lyases, also called CpcT lyases, catalyze the biogenesis of phycobilisome, a light-harvesting antenna complex, through the covalent attachment of chromophores to the antenna proteins. The Arabidopsis CRUMPLED LEAF (CRL) protein is a homolog of the cyanobacterial CpcT lyase. Loss of CRL leads to multiple lesions, including localized foliar cell death, constitutive expression of stress-related nuclear genes, abnormal cell cycle, and impaired plastid division. Notwithstanding the apparent phenotypes, the function of CRL still remains elusive. To gain insight into the function of CRL, we examined whether CRL still retains the capacity to bind with the bacterial chromophore phycocyanobilin (PCB) and its plant analog phytochromobilin (PΦB). The revealed structure of the CpcT domain of CRL is comparable to that of the CpcT lyase, despite the low sequence identity. The subsequent in vitro biochemical assays found, as shown for the CpcT lyase, that PCB/PΦB binds to the CRL dimer. However, some mutant forms of CRL, substantially compromised in their bilin-binding ability, still restore the crl-induced multiple lesions. These results suggest that although CRL retains the bilin-binding pocket, it seems not functionally associated with the crl-induced multiple lesions.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Cianobactérias/enzimologia , Arabidopsis/enzimologia , Proteínas de Arabidopsis/genética , Pigmentos Biliares/metabolismo , Divisão Celular , Liases/genética , Mutação , Fenótipo , Ficobilinas/metabolismo , Ficobiliproteínas/metabolismo , Ficobilissomas/metabolismo , Ficocianina/metabolismo , Plastídeos/metabolismo , Ligação Proteica
19.
Zhongguo Zhong Yao Za Zhi ; 45(24): 6020-6027, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33496143

RESUMO

In ischemic stroke sequela phase, Rehmanniae Radix Praeparata-Corni Fructus drug pair has the effect in protecting damaged neurons, but its mechanism has not been clear. In this study, network pharmacology was used to predict the mechanism of Rehmanniae Radix Praeparata-Corni Fructus in the treatment of ischemic stroke sequela. Through database search and literature retrie-val, 40 active ingredients of Rehmanniae Radix Praeparata and Corni Fructus were obtained, and their targets were obtained through STITCH and TCMSP databases. The targets of ischemic stroke sequela were obtained through OMIM,GAD,TTD and DrugBank databases. By screening the intersections of active ingredients targets and stroke treatment targets, 21 potential targets were obtained. The DAVID database was used for GO enrichment analysis and KEGG pathway analysis of potential targets. GO enrichment analysis showed that Rehmanniae Radix Praeparata-Corni Fructus were mainly involved in regulation of blood pressure, negative regulation of extrinsic apoptotic signaling and positive regulation of angiogenesis. KEGG pathway analysis showed that Rehmanniae Radix Praeparata-Corni Fructus could inhibit inflammatory response and apoptosis signaling pathway by regulating HIF-VEGFA signaling pathway in neural stem cell proliferation, TNF signaling pathway and NF-kappaB signaling pathway. Molecular docking technique was used to verify that Rehmanniae Radix Praeparata-Corni Fructus component has a good binding activity with potential targets. The results showed that in ischemic stroke sequela phase, Rehmanniae Radix Praeparata-Corni Fructus drug pair could play an important role in recovering neural function, promoting the proliferation of neural stem cells, angiogenesis, preventing neural cells apoptosis and regulating inflammatory factors.


Assuntos
Isquemia Encefálica , Cornus , Medicamentos de Ervas Chinesas , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Simulação de Acoplamento Molecular , Tecnologia
20.
RSC Adv ; 10(17): 9985-9995, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35498581

RESUMO

Construction and application of novel hydrogenation catalysts is important for the conversion of carbonyl or aldehyde compounds into alcohols in the field of biomass utilization. In this work, a novel, efficient, and easily prepared hafnium-graphite oxide (Hf-GO) catalyst was constructed via the coordination between Hf4+ and the carboxylic groups in GO. The catalyst was applied into the hydrogenation of biomass derived carbonyl compounds via the Meerwein-Ponndorf-Verley (MPV) reaction. The catalyst gave high efficiency under mild conditions. An interesting phenomenon was found whereby the activity of the catalyst increased gradually in the initial stage during reaction. The solvent, isopropanol, was proved to have an activation effect on the catalyst, and the activation effect varied with different alcohols and temperatures. Further characterizations showed that isopropanol played the activation effect via replacing the residual solvent (DMF) in micro- and mesopores during the preparation process, which was hard to be completely removed by common drying process.

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