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1.
J Synchrotron Radiat ; 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39347700

RESUMO

X-ray ghost imaging with a crystal beam splitter has advantages in highly efficient imaging due to the simultaneous acquisition of signals from both the object beam and reference beam. However, beam splitting with a large field of view, uniform distribution and high correlation has been a great challenge up to now. Therefore, a dedicated beam splitter has been developed by optimizing the optical layout of a synchrotron radiation beamline and the fabrication process of a Laue crystal. A large field of view, consistent size, uniform intensity distribution and high correlation were obtained simultaneously for the two split beams. Modulated by a piece of copper foam upstream of the splitter, a correlation of 92% between the speckle fields of the object and reference beam and a Glauber function of 1.25 were achieved. Taking advantage of synthetic aperture X-ray ghost imaging (SAXGI), a circuit board of size 880 × 330 pixels was successfully imaged with high fidelity. In addition, even though 16 measurements corresponding to a sampling rate of 1% in SAXGI were used for image reconstruction, the skeleton structure of the circuit board can still be determined. In conclusion, the specially developed beam splitter is applicable for the efficient implementation of X-ray ghost imaging.

2.
J Gastroenterol Hepatol ; 39(2): 369-380, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012119

RESUMO

BACKGROUND AND AIM: Triggering receptor expressed on myeloid cells 2 (TREM2) plays crucial roles in metabolic homeostasis and inflammatory response. Altered metabolic function in macrophages could modulate their activation and immune phenotype. The present study aimed to investigate the expression of TREM2 in non-alcoholic fatty liver disease (NAFLD) and to clarify the underlying mechanism of TREM2 on macrophages lipid metabolism and oxidative stress. METHODS: Hepatic TREM2 expression and its relationship with NAFLD progression were analyzed in patients with NAFLD and mice fed a high-fat diet. Lipid metabolism and oxidative stress were investigated in macrophages from NAFLD mice or stimulated with saturated fatty acids. Knockdown and overexpression of TREM2 were further explored. RESULTS: Triggering receptor expressed on myeloid cells 2+ macrophages were increased along with NAFLD development, characterized by aggravated steatosis and liver damage in humans and mice. TREM2 expression was upregulated and lipid metabolism was changed in macrophages from NAFLD mice or metabolically activated by saturated fatty acid in vitro, as demonstrated by increased lipid uptake and catabolism, but reduced de novo synthesis of fatty acids (FAs). Regulation of TREM2 expression in lipid-laden macrophages reprogrammed lipid metabolism, especially the fatty acid oxidation capacity of mitochondria. TREM2 knockdown promoted oxidative stress by aggravating FAs deposition in mitochondria. Intervention of mitochondrial FAs transport in lipid-laden macrophages alleviated FA deposition and reactive oxygen species production induced by TREM2 knockdown. CONCLUSIONS: Triggering receptor expressed on myeloid cells 2 expression was associated with the lipid metabolic profile and reactive oxygen species production in macrophages. High expression of TREM2 in macrophages may protect the liver from oxidative stress in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Liver Int ; 42(12): 2696-2712, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36165186

RESUMO

BACKGROUND & AIMS: Macrophages display remarkable plasticity and can interact with surrounding cells to affect hepatic immunity and tissue remodelling during the progression of liver diseases. Peroxisome proliferator-activated receptor gamma (PPARγ) plays a critical role in macrophage maturation, polarization and metabolism. In this study, we investigated the role of PPARγ in macrophage-hepatic stellate cell (HSC) interaction during non-alcoholic steatohepatitis (NASH) development. METHODS: Wild-type, Ppargfl/fl and PpargΔLyz2 mice were fed a methionine- and choline-deficient (MCD) diet to induce NASH. Depletion of macrophages was performed using an injection of gadolinium chloride intraperitoneally. PPARγ-overexpressing or PPARγ-knockout macrophages were stimulated with saturated fatty acid (SFA) and cocultured with HSCs in a conditioned medium or the transwell coculture system. RESULTS: Depletion of macrophages inhibited HSC activation and ameliorated NASH progression in MCD diet-fed mice. Coculturing HSCs with macrophages or culturing HSCs in a macrophage-conditioned medium-facilitated HSC activation, and this effect was magnified when macrophages were metabolically activated by SFA. Moreover, the absence of PPARγ in macrophages enhanced metabolic activation, promoting the migration and activation of HSCs through IL-1ß and CCL2. In contrast, overexpression of PPARγ in macrophages obtained the opposite effects. In vivo, macrophage-specific PPARγ knockout affected the phenotype of hepatic macrophages and HSCs, involving the MAPK and NLRP3/caspase-1/IL-1ß signalling pathways. Infiltrating hepatic monocyte-derived macrophages became the predominant macrophages in NASH liver, especially in PpargΔLyz2 mice, paralleling with aggravated inflammation and fibrosis. CONCLUSIONS: Regulating macrophage PPARγ affected the metabolic activation of macrophages and their interaction with HSCs. Macrophage-specific PPARγ may be an attractive therapeutic target for protecting against NASH-associated inflammation and fibrosis.


Assuntos
Células Estreladas do Fígado , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Células Estreladas do Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR gama/metabolismo , Meios de Cultivo Condicionados/metabolismo , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Fígado/metabolismo , Cirrose Hepática/patologia , Inflamação/patologia , Metionina/metabolismo
4.
Inorg Chem ; 61(17): 6451-6458, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35438965

RESUMO

Herein, we have successfully synthesized binary Ag2Se, composite Ag0:Ag2Se, and ternary Cu+:Ag2Se through an ambient aqueous-solution-based approach in a one-pot reaction at room temperature and atmospheric pressure without involving high-temperature heating, multiple-processes treatment, and organic solvents/surfactants. Effective controllability over phases and compositions/components are demonstrated with feasibility for large-scale production through an exquisite alteration in reaction parameters especially pH for enhancing and understanding thermoelectric properties. Thermoelectric ZT reaches 0.8-1.1 at near-room-temperature for n-type Ag2Se and Cu+ doping further improves to 0.9-1.2 over a temperature range of 300-393 K, which is the largest compared to that reported by wet chemistry methods. This improvement is related to the enhanced electrical conductivity and the suppressed thermal conductivity due to the incorporation of Cu+ into the lattice of Ag2Se at very low concentrations (x%Cu+:Ag2Se, x = 1.0, 1.5, and 2.0).

5.
Sheng Li Xue Bao ; 73(3): 433-445, 2021 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-34230945

RESUMO

Migraine is a neurological disorder characterized by attacks of moderate or severe headache and various neurological symptoms. Acupuncture, as a commonly used non-pharmacological therapy, has the advantage of obvious therapeutic effect and few side effects in the prevention and treatment of migraine. But the underlying mechanism of acupuncture on migraine remains unclear. Recently, advances in neuroimaging technology have helped to objectively assess the effect of acupuncture on treating migraine and offered new opportunities to explore the central mechanism of acupuncture on treating migraine. In order to better understand the current status of neuroimaging studies on the therapeutic mechanism of acupuncture on migraine and shed light on future research, this review aims to overview the neuroimaging studies in recent 10 years from two aspects: (1) Central mechanism of acupuncture on treating acute migraine attack; (2) Central mechanism of acupuncture on preventing migraine attack.


Assuntos
Terapia por Acupuntura , Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/terapia , Neuroimagem
6.
J Gastroenterol Hepatol ; 35(11): 1998-2008, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32128893

RESUMO

BACKGROUND AND AIM: Chronic inflammation links closely to insulin resistance and lipid metabolism in nonalcoholic fatty liver disease (NAFLD). Macrophage M1 activation plays an important role in the initiation and continuing of pro-inflammatory response of NAFLD. Our study was to investigate whether macrophage M1/M2 polarization switching would affect hepatic inflammation and lipid metabolism through modulation of peroxisome proliferator-activated receptor-gamma (PPAR-γ) activity in vivo and in vitro. METHODS: RAW264.7 macrophages were treated with different fatty acids, and cell culture supernatants were collected to prepare conditioned media (CM). Different co-culture systems between primary hepatocytes and CM from macrophages were established. A PPAR-γ agonist or antagonist was administered to regulate PPAR-γ activity and macrophage polarization. M1/M2 phenotype markers, inflammatory signaling pathway, and lipid-related genes expression were determined. Wild-type C57BL/6 mice were fed a high-fat diet to induce NAFLD and given rosiglitazone to regulate PPAR-γ activity in vivo. RESULTS: Saturated fatty acids induced M1-polarized macrophages while polyunsaturated fatty acids induced M2-polarized macrophages. M1-polarized macrophages significantly promoted lipid synthesis and accumulation in primary hepatocytes through upregulation of a toll-like receptor 4 (TLR4)/NF-κB signaling pathway. The PPAR-γ agonist made lipid-induced M1-polarized macrophages switch to an M2-predominant phenotype, while PPAR-γ antagonist had the opposite effect. Macrophage polarization shifting subsequently affected lipid metabolism in primary hepatocytes. Administration of rosiglitazone improved high-fat diet induced hepatic steatosis and lipid metabolism through reducing hepatic TLR4/NF-κB expression and M1-polarized Kupffer cells. CONCLUSIONS: Lipid-induced macrophage M1 polarization promoted hepatic lipid metabolism. Modulation of PPAR-γ activity could shift macrophage polarization and subsequently affect lipid metabolism. Upregulation of the TLR4/NF-κB signaling pathway is closely linked to dysregulated lipid metabolism in NAFLD.


Assuntos
Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Macrófagos/fisiologia , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR gama/metabolismo , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/metabolismo , Animais , Polaridade Celular , Dieta Hiperlipídica/efeitos adversos , Hepatócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Células RAW 264.7 , Regulação para Cima
7.
Physiol Plant ; 153(3): 419-31, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25132341

RESUMO

Some species of Allium in Liliaceae have fistular leaves. The fistular lamina of Allium fistulosum undergoes a process from solid to hollow during development. The aims were to reveal the process of fistular leaf formation involved in programmed cell death (PCD) and to compare the cytological events in the execution of cell death to those in the unusual leaf perforations or plant aerenchyma formation. In this study, light and transmission electron microscopy were used to characterize the development of fistular leaves and cytological events. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assays and gel electrophoresis were used to determine nuclear DNA cleavage during the PCD. The cavity arises in the leaf blade by degradation of specialized cells, the designated pre-cavity cells, in the center of the leaves. Nuclei of cells within the pre-cavity site become TUNEL-positive, indicating that DNA cleavage is an early event. Gel electrophoresis revealed that DNA internucleosomal cleavage occurred resulting in a characteristic DNA ladder. Ultrastructural analysis of cells at the different stages showed disrupted vacuoles, misshapen nuclei with condensed chromatin, degraded cytoplasm and organelles and emergence of secondary vacuoles. The cell walls degraded last, and residue of degraded cell walls aggregated together. These results revealed that PCD plays a critical role in the development of A. fistulosum fistular leaves. The continuous cavity in A. fistulosum leaves resemble the aerenchyma in the pith of some gramineous plants to improve gas exchange.


Assuntos
Allium/fisiologia , Apoptose , Allium/genética , Allium/ultraestrutura , Morte Celular , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Fragmentação do DNA , DNA de Plantas/genética , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/ultraestrutura , Vacúolos/metabolismo , Vacúolos/ultraestrutura
8.
Heliyon ; 10(3): e24413, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318005

RESUMO

Breast angiosarcoma is a rare and highly aggressive malignancy with a poor prognosis. It can occur spontaneously or be associated with factors such as radiation therapy or chronic lymphedema. The etiology and pathogenesis of this disease are still unclear, the clinical symptoms and imaging findings lack specificity, and the pathological morphology is diverse, which is easy to be confused with other diseases. There is no clear guideline for surgical treatment. Although the optimal surgical approach remains unclear, the ultimate goal is surgical excision with optimal margins, which remains the primary method of treatment. In clinical practice, the choice of the surgical approach should be made by considering the tumor size, pathological type, and patient preferences. In clinical practice, the selection of surgical methods should be carried out with comprehensive consideration of tumor size, pathological types and patients' wishes. There is no clear consensus on whether radiotherapy and chemotherapy should be carried out after surgery, and its optimal program and efficacy are uncertain. This article reviews the etiology, clinical manifestations, pathological features, imaging findings, treatment, prognosis and other aspects of breast angiosarcoma, so as to strengthen clinicians' overall understanding of this disease and avoid missed diagnosis and misdiagnosis.

9.
Front Oncol ; 14: 1378405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665942

RESUMO

Background: The simultaneous occurrence of Branchial Cleft Cyst (BCC) and Papillary Thyroid Carcinoma (PTC) represents an unusual malignant tumor, with cases featuring associated lymph node metastasis being particularly rare. This combination underscores an increased potential for metastasis, and the assessment of neck masses, particularly on the lateral aspect, may inadvertently overlook the scrutiny of the thyroid. Therefore, healthcare providers should exercise vigilance, especially in patients over the age of 40, regarding the potential for neck masses to signify metastasis from thyroid malignancies. Currently, surgical intervention stands as the primary effective curative method, while the postoperative administration of radioactive iodine therapy remains a topic of ongoing debate. Case report: In the presented case, a 48-year-old male patient with a right neck mass underwent surgical intervention. The procedure included the excision of the right neck mass, unilateral thyroidectomy with isthmus resection, and functional neck lymph node dissection under tracheal intubation and general anesthesia. Postoperative pathology findings revealed the coexistence of a BCC with metastatic PTC in the right neck mass, as well as papillary carcinoma in the right thyroid lobe. Lymph node metastasis was observed in the central and levels III of the right neck. Conclusion: The rare amalgamation of a BCC with PTC and concurrent lymph node metastasis underscores the invasive nature of this malignancy. Healthcare professionals should be well-acquainted with its clinical presentation, pathological characteristics, and diagnostic criteria. A multidisciplinary approach is strongly recommended to enhance patient outcomes.

10.
Cell Death Dis ; 15(5): 344, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762508

RESUMO

Lupus nephritis (LN) occurs in 50% of cases of systemic lupus erythematosus (SLE) and is one of the most serious complications that can occur during lupus progression. Mesangial cells (MCs) are intrinsic cells in the kidney that can regulate capillary blood flow, phagocytose apoptotic cells, and secrete vasoactive substances and growth factors. Previous studies have shown that various types of inflammatory cells can activate MCs for hyperproliferation, leading to disruption of the filtration barrier and impairment of renal function in LN. Here, we characterized the heterogeneity of kidney cells of LN mice by single-nucleus RNA sequencing (snRNA-seq) and revealed the interaction between macrophages and MCs through the CXC motif chemokine ligand 12 (CXCL12)/dipeptidyl peptidase 4 (DPP4) axis. In culture, macrophages modulated the proliferation and migration of MCs through this ligand-receptor interaction. In LN mice, treatment with linagliptin, a DPP4 inhibitor, effectively inhibited MC proliferation and reduced urinary protein levels. Together, our findings indicated that targeting the CXCL12/DPP4 axis with linagliptin treatment may serve as a novel strategy for the treatment of LN via the CXCL12/DPP4 axis.


Assuntos
Proliferação de Células , Quimiocina CXCL12 , Dipeptidil Peptidase 4 , Nefrite Lúpica , Macrófagos , Células Mesangiais , Nefrite Lúpica/patologia , Nefrite Lúpica/metabolismo , Animais , Dipeptidil Peptidase 4/metabolismo , Quimiocina CXCL12/metabolismo , Células Mesangiais/metabolismo , Células Mesangiais/patologia , Células Mesangiais/efeitos dos fármacos , Camundongos , Macrófagos/metabolismo , Proliferação de Células/efeitos dos fármacos , Humanos , Feminino , Movimento Celular/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Linagliptina/farmacologia , Transdução de Sinais , Inibidores da Dipeptidil Peptidase IV/farmacologia , Camundongos Endogâmicos C57BL
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