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1.
Sensors (Basel) ; 24(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38676061

RESUMO

The real-time monitoring and fault diagnosis of modern machinery and equipment impose higher demands on equipment maintenance, with the extraction of morphological characteristics of wear debris in lubricating oil emerging as a critical approach for real-time monitoring of wear, holding significant importance in the field. The online visual ferrograph (OLVF) technique serves as a representative method in this study. Various semantic segmentation approaches, such as DeepLabV3+, PSPNet, Segformer, Unet, and other models, are employed to process the oil wear particle image for conducting comparative experiments. In order to accurately segment the minute wear debris in oil abrasive images and mitigate the influence of reflection and bubbles, we propose a multi-level feature reused Unet (MFR Unet) that enhances the residual link strategy of Unet for improved identification of tiny wear debris in ferrograms, leading to superior segmentation results.

2.
Small ; 19(45): e2303654, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37415518

RESUMO

Laser-driven phase transition of 2D transition metal dichalcogenides has attracted much attention due to its high flexibility and rapidity. However, there are some limitations during the laser irradiation process, especially the unsatisfied surface ablation, the inability of nanoscale phase patterning, and the unexploited physical properties of new phase. In this work, the well-controlled femtosecond (fs) laser-driven transformation from the metallic 2M-WS2 to the semiconducting 2H-WS2 is reported, which is confirmed to be a single-crystal to single-crystal transition without layer thinning or obvious ablation. Moreover, a highly ordered 2H/2M nano-periodic phase transition with a resolution of ≈435 nm is achieved, breaking through the existing size bottleneck of laser-driven phase transition, which is attributed to the selective deposition of plasmon energy induced by fs laser. It is also demonstrated that the achieved 2H-WS2 after laser irradiation contains rich sulfur vacancies, which exhibits highly competitive ammonia gas sensing performance, with a detection limit below 0.1 ppm and a fast response/recovery time of 43/67 s at room temperature. This study provides a new strategy for the preparation of the phase-selective transition homojunction and high-performance applications in electronics.

3.
Sensors (Basel) ; 23(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37430803

RESUMO

In order to monitor the diagnosis of mechanical equipment by monitoring the metal wear particles carried in large aperture lubricating oil tubes, the simulation optimization structure design was carried out based on the traditional three-coil inductance wear particle sensor. The numerical model of electromotive force induced by the wear particle sensor was established, and the coil distance and coil turns were simulated by finite element analysis software. When permalloy is covered on the surface of the excitation coil and induction coil, the background magnetic field at the air gap increases, and the induced electromotive force amplitude generated by wear particles is increased. The effect of alloy thickness on the induced voltage and magnetic field was analyzed to determine the optimum thickness, and increase the induction voltage of the alloy chamfer detection at the air gap. The optimal parameter structure was determined to improve the detection ability of the sensor. Ultimately, by comparing the extreme values of the induced voltage of various types of sensors, the simulation determined that the minimum allowable detection of the optimal sensor was 27.5 µm ferromagnetic particles.

4.
Sensors (Basel) ; 22(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36365979

RESUMO

The detection of wear debris in lubricating oil is effective for determining current equipment operating conditions for fault diagnosis. In this paper, a permanent magnet ferromagnetic wear debris sensor is proposed that is composed of a compact structure and a detection coil that generates an induced voltage when wear debris passes through a magnetic field. A three-dimensional model of the sensor is established, the internal axisymmetric high-gradient magnetic field of the sensor is analyzed, and a mathematical model of the sensor signal is proposed. The effects of the air gap structure of the sensor and the relative permeability, velocity, and volume of the wear debris on the sensor performance are analyzed. The correctness of the theoretical results is proven by single particle experiments, and the sensor is calibrated to achieve quantitative analysis of the wear debris.

5.
Acta Pharmacol Sin ; 42(10): 1703-1713, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33927358

RESUMO

Chemotherapy-related fatigue (CRF) is increasingly being recognized as one of the severe symptoms in patients undergoing chemotherapy, which not only largely reduces the quality of life in patients, but also diminishes their physical and social function. At present, there is no effective drug for preventing and treating CRF. Ganoderic acid (GA), isolated from traditional Chinese medicine Ganoderma lucidum, has shown a variety of pharmacological activities such as anti-tumor, anti-inflammation, immunoregulation, etc. In this study, we investigated whether GA possessed anti-fatigue activity against CRF. CT26 tumor-bearing mice were treated with 5-fluorouracil (5-FU, 30 mg/kg) and GA (50 mg/kg) alone or in combination for 18 days. Peripheral and central fatigue-related behaviors, energy metabolism and inflammatory factors were assessed. We demonstrated that co-administration of GA ameliorated 5-FU-induced peripheral muscle fatigue-like behavior via improving muscle quality and mitochondria function, increasing glycogen content and ATP production, reducing lactic acid content and LDH activity, and inhibiting p-AMPK, IL-6 and TNF-α expression in skeletal muscle. Co-administration of GA also retarded the 5-FU-induced central fatigue-like behavior accompanied by down-regulating the expression of IL-6, iNOS and COX2 in the hippocampus through inhibiting TLR4/Myd88/NF-κB pathway. These results suggest that GA could attenuate 5-FU-induced peripheral and central fatigue in tumor-bearing mice, which provides evidence for GA as a potential drug for treatment of CRF in clinic.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Fadiga Muscular/efeitos dos fármacos , Triterpenos/uso terapêutico , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Citocinas/metabolismo , Metabolismo Energético/efeitos dos fármacos , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Camundongos Endogâmicos BALB C , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia
6.
J Clin Gastroenterol ; 54(1): 55-62, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30119093

RESUMO

BACKGROUND: Compared with weekday admissions, weekend admissions are consistently associated with worse patient outcomes, known as the "weekend effect." The weekend effect may have adverse health consequences, including death. To determine the potential impact of the weekend effect on primary (ie, mortality) and secondary outcomes of patients with upper gastrointestinal hemorrhage (UGIH). MATERIALS AND METHODS: This was a network meta-analysis based on cohort studies. Databases were searched for studies published up to April 2018. The predefined primary outcome was mortality (30-d mortality and in-hospital mortality). The secondary efficacy outcomes were rebleeding rates, use of endoscopic therapy, need for surgery or angiography, mean length of hospital stay, and time to endoscopy. The study protocol was registered with PROSPERO (No. CRD42018094660). RESULTS: In total, 25 studies, including 28 analyses (N=1,203,202 patients), were eligible. The results revealed a tendency toward increased 30-day mortality and increased in-hospital mortality among weekend admissions. In a subgroup analysis, there were significance differences in mortality according to the study location (ie, Europe) and UGIH type (ie, variceal UGIH), with these subgroups having elevated mortality rates. Moreover, weekday admissions were associated with a significant decrease in rebleeding rates. In the network meta-analysis, the study location (in Europe or Asia) and type of UGIH (ie, variceal UGIH) were associated with an increased likelihood of high in-hospital mortality among weekend admissions. CONCLUSIONS: The evidence derived from this network meta-analysis supports the idea that weekend admissions are associated with an increased risk of death, especially among variceal UGIH patients in European hospitals.


Assuntos
Gastroenteropatias/mortalidade , Hemorragia Gastrointestinal/mortalidade , Mortalidade Hospitalar/tendências , Admissão do Paciente/estatística & dados numéricos , Fatores de Tempo , Europa (Continente) , Gastroenteropatias/terapia , Hemorragia Gastrointestinal/terapia , Hospitais/estatística & dados numéricos , Humanos , Metanálise em Rede , Periodicidade , Estudos Prospectivos , Estudos Retrospectivos , Trato Gastrointestinal Superior
7.
Blood ; 121(10): 1760-8, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23299310

RESUMO

Myeloid-derived suppressor cells (MDSCs) play an important role in the regulation of the immune response. MDSC expansion occurs in many circumstances, including cancer, inflammation, stresses, and transplant tolerance. Liver transplants in mice are spontaneously accepted, but hepatocyte transplants are acutely rejected, suggesting the immunoregulatory activities of liver nonparenchymal cells. We have reported that hepatic stellate cells (HpSCs), the stromal cells in the liver, are immensely immunosuppressive and can effectively protect islet transplants via induction of MDSCs. The present study shows that the addition of HpSCs into dendritic cell (DC) culture promoted development of MDSCs, instead of DCs, which was highly dependent on complement component 3 (C3) from HpSCs. The C3(-/-) HpSCs lost their ability to induce MDSCs and, consequently, failed to protect the cotransplanted islet allografts. HpSCs produced complement activation factor B and factor D which then enhanced C3 cleavage to activation products iC3b and C3d. Addition of exogenous iC3b, but not C3d, into the DC culture led to the differentiation of MDSCs with potent immune-inhibitory function. These findings provide novel mechanistic insights into the differentiation of myeloid cells mediated by local tissue cells, and may assist in the development of MDSC-based therapy in clinical settings.


Assuntos
Diferenciação Celular/imunologia , Complemento C3/fisiologia , Células Dendríticas/imunologia , Células Estreladas do Fígado/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Células Mieloides/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Western Blotting , Células Dendríticas/citologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/prevenção & controle , Citometria de Fluxo , Sobrevivência de Enxerto , Células Estreladas do Fígado/patologia , Células Estreladas do Fígado/transplante , Técnicas Imunoenzimáticas , Terapia de Imunossupressão , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/citologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Transplante Homólogo
8.
Int J Biol Macromol ; 261(Pt 2): 129793, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290627

RESUMO

A water-soluble glycopeptide (named GL-PWQ3) with a molecular weight (Mw) of 2.40 × 104 g/mol was isolated from Ganoderma lucidum fruiting body by hot water extraction, membrane ultrafiltration, and gel column chromatography, which mainly consisted of glucose and galactose. Based on the methylation, FT-IR, 1D, and 2D NMR analysis, the polysaccharide portion of GL-PWQ3 was identified as a glucogalactan, which was comprised of unsubstituted (1,6-α-Galp, 1,6-ß-Glcp, 1,4-ß-Glcp) and monosubstituted (1,2,6-α-Galp and 1,3,6-ß-Glcp) in the backbone and possible branches that at the O-3 position of 1,3-Glcp and T-Glcp, and the O-2 position of T-Fucp, T-Manp or T-Glcp. The chain conformational study by SEC-MALLS-RI and AFM revealed that GL-PWQ3 was identified as a highly branched polysaccharide with a polydispersity index of 1.25, and might have compact sphere structures caused by stacked multiple chains. Moreover, the GL-PWQ3 shows strong anti-oxidative activity in NRK-52E cells. This study provides a theoretical basis for further elucidating the structure-functionality relationships of GL-PWQ3 and its potential application as a natural antioxidant in pharmacotherapy as well as functional food additives.


Assuntos
Reishi , Reishi/química , Espectroscopia de Infravermelho com Transformada de Fourier , Polissacarídeos/química , Glucose/análise , Peso Molecular , Água
9.
Clin Dev Immunol ; 2013: 389807, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23737812

RESUMO

Hepatic stellate cells (HSCs) interact with immune cells to actively participate in regulating immune response in the liver which is mediated by the effector molecules, including B7-H1. We demonstrated here that expression of B7-H1 on HSCs was markedly enhanced by interferon-(IFN-) γ stimulation. IFN- γ stimulated HSCs inhibited T-cell proliferation via induction of T-cell apoptosis (22.1% ± 1.6%). This immunosuppressive effect was inhibited by preincubation with an anti-B7-H1 antibody, or inhibitor of the MEK/ERK pathway inhibited IFN- γ mediated expression of B7-H1. Thus, regulation of B7-H1 expression on HSCs by IFN- γ represents an important mechanism that regulates immune responses in the liver favoring tolerogenicity rather than immunogenicity. Involvement of MEK/ERK pathway provides a novel target for therapeutic approaches.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Interferon gama/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Animais , Antracenos/farmacologia , Anticorpos Neutralizantes/farmacologia , Apoptose , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Proliferação de Células , Cromonas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/imunologia , Tolerância Imunológica , Teste de Cultura Mista de Linfócitos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/genética , Morfolinas/farmacologia , Transdução de Sinais/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia
10.
Front Pharmacol ; 14: 1287908, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841924

RESUMO

Introduction: In the Doxorubicin (DOX)-induced nephropathy model, proteinuria is a manifestation of progressive kidney injury. The pathophysiology of renal illness is heavily influenced by the renin-angiotensin system (RAS). To reduce renal RAS activation and proteinuria caused by DOX, this study evaluated the effectiveness of Ganoderma lucidum polysaccharide peptide (GL-PP), a new glycopeptide produced from Ganoderma lucidum grown on grass. Methods: Three groups of BALB/c male mice were created: control, DOX, and DOX + GL-PP. GL-PP (100 mg/kg) was administered to mice by intraperitoneal injection for 4 weeks following a single intravenous injection of DOX (10 mg/kg via the tail vein). Results: After 4 weeks, full-length and soluble pro(renin) receptor (fPRR/sPRR) overexpression in DOX mouse kidneys, which is crucial for the RAS pathway, was dramatically inhibited by GL-PP therapy. Additionally, GL-PP successfully reduced elevation of urinary renin activity and angiotensin II levels, supporting the idea that GL-PP inhibits RAS activation. Moreover, GL-PP showed a considerable downregulation of nicotinamide adenine nucleotide phosphate oxidase 4 (NOX4) expression and a decrease in hydrogen peroxide (H2O2) levels. GL-PP treatment effectively reduced glomerular and tubular injury induced by DOX, as evidenced by decreased proteinuria, podocyte damage, inflammation, oxidative stress, apoptosis, and fibrosis. Discussion: GL-PP inhibits intrarenal PRR/sPRR-RAS activation and upregulation of NOX4 and H2O2, suggesting potential therapeutic approaches against DOX-induced nephropathy.

11.
Int J Biol Macromol ; 253(Pt 7): 127336, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37852403

RESUMO

Excessive proteinuria leads to renal dysfunction and damage. Ganoderma lucidum polysaccharide peptide (GL-PP) and Ganoderma lucidum polysaccharide peptide 2 (GL-PP2) are biologically active compounds extracted from Ganoderma lucidum. GL-PP has a relative molecular weight of 37,121 with 76.39 % polysaccharides and 16.35 % polypeptides, while GL-PP2 has a relative molecular weight of 31,130, composed of 64.14 % polysaccharides and 17.73 % polypeptides. The xylose: mannose: glucose monosaccharide ratios in GL-PP and GL-PP2 were 4.83:1:7.03 and 2.35:1:9.38, respectively. In this study, we investigated the protective effects of GL-PP and GL-PP2 on proteinuria-induced renal dysfunction and damage using rat and cell models. Both compounds reduced kidney injury, proteinuria, and inhibited the (pro)renin receptor (PRR)-renin-angiotensin system (RAS) pathway, inflammatory cell infiltration, oxidative stress, and fibrosis. GL-PP2 showed stronger inhibition of cyclooxygenase-2 and inducible nitric oxide synthase proteins compared to GL-PP. In cell models, both compounds displayed anti-inflammatory properties and improved cellular viability by inhibiting the PRR-RAS pathway. GL-PP2 has higher feasibility and productivity than GL-PP in pharmacology and industrial production. It shows promise in treating proteinuria-induced renal disease with superior anti-inflammatory effects and economic, safe industrial application prospects. Further research is needed to compare efficacy, mechanisms, clinical applications, and commercial feasibility of GL-PP and GL-PP2.


Assuntos
Ganoderma , Nefropatias , Reishi , Ratos , Animais , Reishi/química , Sistema Renina-Angiotensina , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/química , Nefropatias/tratamento farmacológico , Proteinúria/tratamento farmacológico , Peptídeos/farmacologia , Anti-Inflamatórios
12.
Phytomedicine ; 119: 155010, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37586160

RESUMO

BACKGROUND: Not many drugs with fewer side effects are available for the treatment of rheumatoid arthritis (RA). Ganoderma lucidum polysaccharide peptide (GLPP) has good immunomodulatory effects, but whether it is effective in managing RA is not clear. PURPOSE: This study was conducted to examine the anti-RA activity and possible mechanisms of GLPP in collagen-induced arthritis (CIA) rats. METHODS: Male Wistar rats were intradermally injected with bovine type II collagen in the tail base to establish the CIA model and were orally administered 100 or 200 mg/kg GLPP for 35 days. Paw thickness, clinical arthritis scores, gait analysis, organ index determination, blood cell counts, micro-CT imaging and pathological staining were performed on the rats. Liver and kidney function were measured by commercial kits, and antibody levels were measured by ELISA kits. RA-related protein levels were detected by Western blotting. RESULTS: GLPP effectively alleviated CIA symptoms and reduced immune organ indexes, antibody levels and systemic organ injury. GLPP decreased the protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, matrix metalloproteinase (MMP)2, MMP9, MMP13, BCL-2, OPN, ß-Catenin, and hypoxia inducible factor (HIF)-1α and increased the protein expression of BAX in the joint tissues of CIA rats. Moreover, GLPP decreased the phosphorylation levels of p65, IκB-α and ERK1/2. CONCLUSION: GLPP effectively alleviated RA symptoms in CIA rats by inhibiting the NF-κB and MAPK pathways. This study suggests a promising therapeutic effect of mushroom-derived polysaccharide peptides on RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Reishi , Febre Reumática , Ratos , Masculino , Animais , Bovinos , NF-kappa B/metabolismo , Sistema de Sinalização das MAP Quinases , Ratos Wistar , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Artrite Experimental/patologia , Fator de Necrose Tumoral alfa/metabolismo , Citocinas/metabolismo
13.
Comput Struct Biotechnol J ; 21: 2780-2791, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181660

RESUMO

Tumor targeting drug delivery is of significant importance for the treatment of triple negative breast cancer (TNBC) considering the presence of appreciable amount of tumor matrix and the absence of effective targets on the tumor cells. Hence in this study, a new therapeutic multifunctional nanoplatform with improved TNBC targeting ability and efficacy was constructed and used for therapy of TNBC. Specifically, curcumin loaded mesoporous polydopamine (mPDA/Cur) nanoparticles were synthesized. Thereafter, manganese dioxide (MnO2) and a hybrid of cancer-associated fibroblasts (CAFs) membranes as well as cancer cell membranes were sequentially coated on the surface of mPDA/Cur to obtain mPDA/Cur@M/CM. It was found that two distinct kinds of cell membranes were able to endow the nano platform with homologous targeting ability, thereby achieving accurate delivery of drugs. Nanoparticles gathered in the tumor matrix can loosen the tumor matrix via the photothermal effect mediated by mPDA to rupture the physical barrier of tumor, which is conducive to the penetration and targeting of drugs to tumor cells in the deep tissues. Moreover, the existence of curcumin, MnO2 and mPDA was able to promote the apoptosis of cancer cells by promoting increased cytotoxicity, enhanced Fenton-like reaction, and thermal damage, respectively. Overall, both in vitro and in vivo results showed that the designed biomimetic nanoplatform could significantly inhibit the tumor growth and thus provide an efficient novel therapeutic strategy for TNBC.

14.
Hepatology ; 53(3): 1007-19, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21374665

RESUMO

UNLABELLED: Although organ transplants have been applied for decades, outcomes of somatic cell transplants remain disappointing, presumably due to lack of appropriate supporting stromal cells. Thus, cotransplantation with liver stromal cells, hepatic stellate cells (HSC), achieves long-term survival of islet allografts in mice by way of induction of effector T cell apoptosis and generation of regulatory T (Treg) cells. In this study we provide evidence both in vitro and in vivo that HSC can promote generation of myeloid-derived suppressor cells (MDSC). HSC-induced MDSC demonstrate potent immune inhibitory activity. Induction of MDSC is dependent on an intact interferon gamma signaling pathway in HSC and is mediated by soluble factors, suggesting that the specific tissue stromal cells, such as HSC, play a crucial role in regulating immune response by way of inflammation-induced generation of MDSC. Large amounts of MDSC can be propagated in vitro from bone marrow-derived myeloid precursor cells under the influence of HSC. CONCLUSION: Cotransplantation with in vitro generated MDSC can effectively protect islet allografts from host immune attack. Local delivery of potent immune suppressor cells for cell transplants holds great clinical application potential.


Assuntos
Células Estreladas do Fígado/imunologia , Células Mieloides/imunologia , Animais , Células Estreladas do Fígado/transplante , Interferon gama/fisiologia , Transplante das Ilhotas Pancreáticas/imunologia , Transplante das Ilhotas Pancreáticas/métodos , Masculino , Camundongos , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/fisiologia , Transplante Homólogo
15.
J Surg Res ; 174(1): e37-45, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22225980

RESUMO

BACKGROUND: Hepatic artery vasoconstriction plays a major role in the pathophysiology of the small-for-size (SFS) liver graft injury and is reversed by adenosine. The A2a adenosine receptor (AR) has been suggested to be one of the key receptors that modulate hepatic hemodynamic changes. The aim of the study is to define the effects of the A2a AR agonist, regadenoson, in modulating hepatic artery flow (HAF) in SFS liver grafts of a porcine model. METHODS: Seven female recipient pigs (66-70 kg) receiving 20% liver grafts were treated with regadenoson, 0.1 ug/kg/min starting on POD1 (n = 7). Results were compared with those with untreated 20% liver grafts (n= 8). The recipients were observed for 14 d. Hepatic artery flow (HAF) and portal vein flow (PVF) were recorded. Liver biopsies and serum samples were also taken at the designed time points through postoperative day (POD)14. RESULTS: Dose-response curves of regadenoson established 0.1 ug/kg/min as the most effective dose of regadenoson for maintaining an increase in HAF. No adverse effects were seen with regadenoson infusion. HAF immediately increased by up to 2.2-fold after regadenoson infusion. The levels of daily average of HAF and percentage of HAF in total liver blood flow were 34.5% and 41.8%, respectively, higher in the regadenoson group than in the untreated group. Histologic scores of hepatic artery spasm and bile duct necrosis were significantly lower in the regadenoson group than in the untreated group (P = 0.01 and 0.04, respectively). The complication rates of hepatic artery thrombosis and gastrointestinal bleeding were lower in the regadenoson group than in the untreated group (0/7, 0% versus 2/8, 25% and 0/7, 0% versus 2/8 and 25%, respectively). The 14-d survival rates were 4/7 (57.1 %) in regadenoson group compared with 2/8 (25%) in the untreated group. CONCLUSION: Adenosine A2a AR agonist, regadenoson, increases HAF in the recipients of SFS grafts with modest improvements in outcome.


Assuntos
Agonistas do Receptor A2 de Adenosina/farmacologia , Artéria Hepática/efeitos dos fármacos , Circulação Hepática/efeitos dos fármacos , Transplante de Fígado , Purinas/farmacologia , Pirazóis/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Artéria Hepática/fisiologia , Fígado/patologia , Tamanho do Órgão , Cuidados Pós-Operatórios , Receptor A2A de Adenosina/fisiologia , Taxa de Sobrevida , Suínos
16.
J Surg Res ; 174(1): 157-65, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21195421

RESUMO

BACKGROUND: Elevated levels of norepinephrine (NE) have been reported in recipients of small-for-size liver (SFS) grafts in the perioperative period. The aim of the study is to test the hypothesis that although circulating catecholamines are elevated in recipients of SFS grafts, they are not the primary agents responsible for the hepatic artery (HA) vasospasm. METHODS: Female porcine recipients receiving a 20% (n = 10) partial liver graft were compared with a control group, using 60% partial liver transplanted grafts (n = 9). Hepatic blood flow (PVF, HAF) and levels of plasma catecholamines (epinephrine and NE) were measured at designated time points through postoperative day (POD) 7. Phentolamine (PA), an α-adrenergic blocker, was administered at doses of 1 to 112.5 ug/kg/min through an indwelling HA to the recipients of 20% group on POD1 (n = 5). RESULTS: In the 20% group following reperfusion, HA vasospasm was found at 10, 60, and 90 min, and persisted on POD 3 and POD 7. Plasma NE levels increased after reperfusion in 20% and 60% groups and peaked at 6 h with 10- to 13-fold increased levels compared with baseline. In the 20% group, NE levels remained elevated up to POD 7. PA infusion at low (1-10 ug/kg/min) and high (12.5-112.5 ug/kg/min) doses did not reverse the reduced HAF observed in 20% group recipients. CONCLUSION: Elevated serum NE does not appear to be the primary factor mediating HA vasospasm in the porcine SFS graft.


Assuntos
Catecolaminas/sangue , Artéria Hepática , Transplante de Fígado/efeitos adversos , Doenças Vasculares/etiologia , Animais , Feminino , Fígado/patologia , Circulação Hepática , Tamanho do Órgão , Suínos
17.
Nanoscale ; 14(23): 8349-8361, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35635070

RESUMO

The absence of effective therapeutic targets and tumor hypoxia are the main causes of failure in the treatment of triple-negative breast cancer (TNBC). Biomimetic nanotechnology and tumor microenvironment (TME) responsiveness bring hope and opportunity to address this problem. Here, we develop a core membrane nanoplatform (HM/D-I-BL) using hollow mesoporous manganese dioxide (HM) coated with a biomimetic cancer cell membrane for enhanced chemotherapy/phototherapy via the strategy of precise drug delivery and hypoxia amelioration. Cancer cell membrane modification endows HM/D-I-BL with excellent homologous targeting and immune escape performance. Cellular uptake and fluorescence imaging studies confirmed that HM/D-I-BL can be accurately delivered to tumor sites. HM/D-I-BL also features efficient in situ O2 generation in tumors upon laser irradiation, and subsequently enhanced chemotherapy/phototherapy, pointing to its usefulness as a TME-responsive nanozyme to alleviate tumor hypoxia in the presence of H2O2. In addition, HM/D-I-BL showed good fluorescence and magnetic resonance imaging performances, which offers a reliable multimodal image-guided combination tumor therapy for precision theranostics in the future. In general, this intelligent biomimetic nanoplatform with its homotypic tumor targeting, in situ alleviation of tumor hypoxia and synergetic chemophototherapy would open up a new dimension for the precision treatment of TNBC.


Assuntos
Nanopartículas , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Peróxido de Hidrogênio/farmacologia , Fototerapia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral
18.
Plant Sci ; 325: 111461, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36122814

RESUMO

Phellodendron amurense (Rupr.) is a well-known medicinal plant with high medicinal value, and its various tissues are enriched in various active pharmaceutical ingredients. Isoquinoline alkaloids are the primary medicinal component of P. amurense and have multiple effects, such as anti-inflammation, antihypertension, and antitumor effects. However, the potential regulatory mechanism of isoquinoline alkaloid biosynthesis during stem development in P. amurense is still poorly understood. In the present study, a total of eight plant hormones for each stem development stage were detected; of those, auxin, gibberellins and brassinosteroids were significantly highly increased in perennial stems and played key roles during stem development in P. amurense. We also investigated the content and change pattern of secondary metabolites and comprehensively identified some key structural genes involved in the isoquinoline alkaloid biosynthesis pathway by combining the transcriptome and metabolomics. A total of 39,978 DEGs were identified in the present study, and six of those had candidate structural genes (NCS, GOT2, TYNA, CODM, TYR, TAT and PSOMT1) that were specifically related to isoquinoline alkaloid biosynthesis in P. amurense. Corydalmine, cyclanoline, dehydroyanhunine, (S)-canadine and corybulbine were the most significantly upregulated metabolites among the different comparative groups. Three differentially expressed metabolites, dopamine, (S)-corytuberine and (S)-canadine, were enriched in the isoquinoline alkaloid biosynthesis pathway. Furthermore, bHLH and WRKY transcription factors play key roles in the isoquinoline alkaloid biosynthesis pathway in P. amurense. The results not only provide comprehensive genetic information for understanding the molecular mechanisms of isoquinoline alkaloid biosynthesis but also lay a foundation for the combinatory usage of the medicinal active ingredient of P. amurense.


Assuntos
Alcaloides , Phellodendron , Phellodendron/genética , Transcriptoma , Metaboloma , Isoquinolinas
19.
Food Funct ; 12(24): 12325-12337, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34821902

RESUMO

5-Fluorouracil (5-FU) is a chemotherapeutic drug with a good anti-cancer effect on various types of cancers, such as colorectal cancer and breast cancer. However, previous studies have found that 5-FU could induce cognitive deficit in clinics. As ganoderic acid, isolated from Ganoderma lucidum, has a protective effect on neurons, this study investigated the effects of ganoderic acid (GA) against 5-FU-induced cognitive dysfunction with a series of behavioral tests and related indicators. Experimental results showed that GA significantly prevented the reduction of spatial and non-spatial memory in 5-FU-treated mice. In addition, GA not only ameliorated the damage to hippocampal neurons and mitochondrial structure, but also significantly improved abnormal protein expression of mitochondrial biogenesis related marker PGC-1α, and mitochondrial dynamics related markers MFN2, DRP1 and FIS1 in the hippocampi of 5-FU-treated mice. Moreover, GA could up-regulate the expression of neuronal survival and growth-related proteins, such as BDNF, p-ERK, p-CREB, p-Akt, p-GSK3ß, Nrf2, p-mTOR, and p-S6, in the hippocampi of 5-FU-treated mice. These results suggest that GA could prevent cognitive dysfunction in mice treated with 5-FU via preventing mitochondrial impairment and enhancing neuronal survival and growth, which provide evidence for GA as a promising adjunctive therapy for chemotherapy related cognitive impairment in clinics.


Assuntos
Disfunção Cognitiva/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Reishi , Triterpenos/farmacologia , Animais , Antineoplásicos/efeitos adversos , Modelos Animais de Doenças , Fluoruracila/efeitos adversos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Fitoterapia , Distribuição Aleatória , Triterpenos/uso terapêutico
20.
Hepatology ; 50(6): 1981-91, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19821484

RESUMO

UNLABELLED: The liver is considered to be an immune-privileged organ that favors the induction of tolerance. The underlying mechanisms are not completely understood. Interestingly, liver transplants are spontaneously accepted in several animal models, but hepatocyte transplants are acutely rejected, suggesting that liver nonparenchymal cells may effectively protect the parenchymal cells from immune attack. We have shown the profound T cell inhibitory activity of hepatic stellate cells (HSCs). Thus, cotransplantation with HSCs effectively protects islet allografts from rejection in mice. In this study, using T cell receptor transgenic and gene knockout approaches, we provided definitive evidence that HSCs protected cotransplanted islet allografts by exerting comprehensive inhibitory effects on T cells, including apoptotic death in graft-infiltrating antigen-specific effector T cells and marked expansion of CD4(+) Forkhead box protein (Foxp)3(+) T regulatory (Treg) cells. All these effects required an intact interferon-gamma (IFN-gamma) signaling in HSCs, demonstrated by using HSCs isolated from IFN-gamma receptor 1 knockout mice. B7-H1 expression on HSCs, a product molecule of IFN-gamma signaling, was responsible for induction of T cells apoptosis, but had no effect on expansion of Treg cells, suggesting that undetermined effector molecules produced by IFN-gamma signaling is involved in this process. CONCLUSION: Upon inflammatory stimulation, specific organ stromal cells (such as HSCs in the liver) demonstrate potent immune regulatory activity. Understanding of the mechanisms involved may lead to development of novel strategies for clinical applications in transplantation and autoimmune diseases.


Assuntos
Células Estreladas do Fígado/imunologia , Interferon gama/fisiologia , Transdução de Sinais/fisiologia , Animais , Apoptose , Antígeno B7-1/genética , Antígeno B7-1/fisiologia , Antígeno B7-H1 , Linfócitos T CD8-Positivos/imunologia , Fatores de Transcrição Forkhead/fisiologia , Transplante das Ilhotas Pancreáticas , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos , Peptídeos/genética , Peptídeos/fisiologia , Receptores de Interferon/fisiologia , Linfócitos T Reguladores/fisiologia , Receptor de Interferon gama
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