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1.
Natl Sci Rev ; 11(7): nwae209, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39071098

RESUMO

Conventional bone scaffolds, which are mainly ascribed to highly active osteoclasts and an inflammatory microenvironment with high levels of reactive oxygen species and pro-inflammatory factors, barely satisfy osteoporotic defect repair. Herein, multifunctional self-assembled supramolecular fiber hydrogels (Ce-Aln gel) consisting of alendronate (Aln) and cerium (Ce) ions were constructed for osteoporotic bone defect repair. Based on the reversible interaction and polyvalent cerium ions, the Ce-Aln gel, which was mainly composed of ionic coordination and hydrogen bonds, displayed good injectability and autocatalytic amplification of the antioxidant effect. In vitro studies showed that the Ce-Aln gel effectively maintained the biological function of osteoblasts by regulating redox homeostasis and improved the inflammatory microenvironment to enhance the inhibitory effect on osteoclasts. Ribonucleic acid (RNA) sequencing further revealed significant downregulation of various metabolic pathways, including apoptosis signaling, hypoxia metabolism and tumor necrosis factor-alpha (TNF-α) signaling via the nuclear factor kappa-B pathway after treatment with the Ce-Aln gel. In vivo experiments showed that the clinical drug-based Ce-Aln gel effectively promoted the tissue repair of osteoporotic bone defects by improving inflammation and inhibiting osteoclast formation at the defect. Notably, in vivo systemic osteoporosis was significantly ameliorated, highlighting the strong potential of clinical translation for precise therapy of bone defects.

2.
ACS Nano ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010657

RESUMO

Pyroptosis is an inflammatory form of programmed cell death associated with the immune system that can be induced by reactive oxygen species (ROS). As a therapeutic strategy with better penetration depth, sonodynamic therapy (SDT) is expected to induce pyroptosis of cancer cells and boost the immune response. However, it is still a limited problem to precisely adjust the structure of sonosensitizers to exhibit satisfactory sono-catalytic properties. Herein, fluorinated titanium oxide (TiO2-xFx) sonosensitizers were developed to induce pyroptosis under ultrasound (US) to boost antitumor immune responses, enabling highly effective SDT. On the one hand, the introduction of F atoms significantly reduced the adsorption energy of TiO2-xFx for oxygen and water, which is conducive to the occurrence of sono-catalytic reactions. On the other hand, the process of F replacing O increased the oxygen vacancies of the sonosensitizer and shortened the band gap, which enabled powerful ROS generation ability under US stimulation. In this case, large amounts of ROS could effectively kill cancer cells by inducing mitochondrial damage and disrupting oxidative homeostasis, leading to significant cell pyroptosis. Moreover, SDT treatment with TiO2-xFx not only suppressed tumor proliferation but also elicited robust immune memory effects and hindered tumor recurrence. This work highlighted the importance of precisely regulating the structure of sonosensitizers to achieve efficient ROS generation for inducing pyroptosis, which sets the stage for the further development of SDT-immunotherapy.

3.
Technol Health Care ; 32(S1): 299-312, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38759058

RESUMO

BACKGROUND: Plane-wave imaging is widely employed in medical imaging due to its ultra-fast imaging speed. However, the image quality is compromised. Existing techniques to enhance image quality tend to sacrifice the imaging frame rate. OBJECTIVE: The study aims to reconstruct high-quality plane-wave images while maintaining the imaging frame rate. METHODS: The proposed method utilizes a U-Net-based generator incorporating a multi-scale convolution module in the encoder to extract information at different levels. Additionally, a Dynamic Criss-Cross Attention (DCCA) mechanism is proposed in the decoder of the U-Net-based generator to extract both local and global features of plane-wave images while avoiding interference caused by irrelevant regions. RESULTS: In the reconstruction of point targets, the experimental images achieved a reduction in Full Width at Half Maximum (FWHM) of 0.0499 mm, compared to the Coherent Plane-Wave Compounding (CPWC) method using 75-beam plane waves. For the reconstruction of cyst targets, the simulated image achieved a 3.78% improvement in Contrast Ratio (CR) compared to CPWC. CONCLUSIONS: The proposed model effectively addresses the issue of unclear lesion sites in plane-wave images.


Assuntos
Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
4.
ACS Nano ; 18(15): 10495-10508, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38556991

RESUMO

Sonodynamic therapy (SDT) has promising application prospects in tumor therapy. However, SDT does not eradicate metastatic tumors. Herein, Cu-substituted ZnAl ternary layered double hydroxide nanosheets (ZCA NSs) were developed as both sonosensitizers and copper nanocarriers for synergistic SDT/cuproptosis cancer therapy. An optimized electronic structure more conducive to the sonodynamic process was obtained from ZCA NSs via the Jahn-Teller effect induced by the introduction of Cu2+, and the synthesized ZCA NSs regulated the intricate tumor microenvironment (TME) by depleting endogenous glutathione (GSH) to amplify oxidative stress for further enhanced SDT performance. Furthermore, cuproptosis was evoked by intracellular overload of Cu2+ and amplified by SDT, leading to irreversible proteotoxicity. In vitro results showed that such synergetic SDT/cuproptosis triggered immunogenic cell death (ICD) and promoted the maturation of dendritic cells (DCs). Furthermore, the as-synthesized ZCA NS-mediated SDT/cuproptosis thoroughly eradicated the in vivo solid tumors and simultaneously elicited antitumor immunity to suppress lung and liver metastasis. Overall, this work established a nanoplatform for synergistic SDT/cuproptosis with a satisfactory antitumor immunity.


Assuntos
Neoplasias Hepáticas , Neoplasias , Terapia por Ultrassom , Humanos , Cobre , Eletrônica , Glutationa , Hidróxidos , Neoplasias Hepáticas/tratamento farmacológico , Imunidade , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Microambiente Tumoral
5.
Exploration (Beijing) ; 3(1): 20220041, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37323619

RESUMO

Oxidative stress from reactive oxygen species (ROS) is a reperfusion injury factor that can lead to cell damage and death. Here, ultrasmall iron-gallic acid coordination polymer nanodots (Fe-GA CPNs) were developed as antioxidative neuroprotectors for ischemia stroke therapy guided by PET/MR imaging. As proven by the electron spin resonance spectrum, the ultrasmall Fe-GA CPNs with ultrasmall size, scavenged ROS efficiently. In vitro experiments revealed that Fe-GA CPNs could protect cell viability after being treated with hydrogen peroxide (H2O2) and displayed the effective elimination of ROS by Fe-GA CPNs, which subsequently restores oxidation balance. When analyzing the middle cerebral artery occlusion model, the neurologic damage displayed by PET/MR imaging revealed a distinct recovery after treatment with Fe-GA CPNs, which was proved by 2,3,5-triphenyl tetrazolium chloride staining. Furthermore, immunohistochemistry staining indicated that Fe-GA CPNs inhibited apoptosis through protein kinase B (Akt) restoration, whereas western blot and immunofluorescence indicated the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) pathway following Fe-GA CPNs application. Therefore, Fe-GA CPNs exhibit an impressive antioxidative and neuroprotective role via redox homeostasis recovery by Akt and Nrf2/HO-1 pathway activation, revealing its potential for clinical ischemia stroke treatment.

6.
Acta Pharm Sin B ; 13(4): 1726-1739, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37139421

RESUMO

Oxidative stress, due to the disruption of the balance between reactive oxygen species (ROS) generation and the antioxidant defense system, plays an important role in the pathogenesis of rheumatoid arthritis (RA). Excessive ROS leads to the loss of biological molecules and cellular functions, release of many inflammatory mediators, stimulate the polarization of macrophages, and aggravate the inflammatory response, thus promoting osteoclasts and bone damage. Therefore, foreign antioxidants would effectively treat RA. Herein, ultrasmall iron-quercetin natural coordination nanoparticles (Fe-Qur NCNs) with excellent anti-inflammatory and antioxidant properties were constructed to effectively treat RA. Fe-Qur NCNs obtained by simple mixing retain the inherent ability to remove ROS of quercetin and have a better water-solubility and biocompatibility. In vitro experiments showed that Fe-Qur NCNs could effectively remove excess ROS, avoid cell apoptosis, and inhibit the polarization of inflammatory macrophages by reducing the activation of the nuclear factor-κ-gene binding (NF-κB) pathways. In vivo experiments showed that the swollen joints of mice with rheumatoid arthritis treated with Fe-Qur NCNs significantly improved, with Fe-Qur NCNs largely reducing inflammatory cell infiltration, increasing anti-inflammatory macrophage phenotypes, and thus inhibiting osteoclasts, which led to bone erosion. This study demonstrated that the new metal-natural coordination nanoparticles could be an effective therapeutic agent for the prevention of RA and other diseases associated with oxidative stress.

7.
Bioact Mater ; 25: 73-85, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36733928

RESUMO

Osteosarcoma (OS) patients have a poor prognosis due to its high degree of heterogeneity and high rate of metastasis. Magnetic hyperthermia therapy (MHT) combined with immunotherapy is an effective strategy to treat solid and metastatic tumors. Here, we combined biodegradable magnesium (Mg) macroscale rods, which acted as an eddy thermo-magnetic agent under a low external alternating magnetic field, and immunotherapy to achieve a radical cure for OS. The eddy thermal effect (ETE) of the Mg rods (MgR) showed outstanding cytotoxic effects and enhanced the maturation of dendritic cells (DCs), and the mild MHT induced the immunogenic cell death (ICD) in the OS cells. Combined with immune checkpoint blockade (ICB) therapy, we obtained an excellent curative effect against OS, and a further evaluation demonstrated that the local MHT induced by the MgR increased T cells infiltration and the polarization of M1 macrophages. Interestingly, the biodegradable MgR also promoted bone osteogenesis. Our work highlighted the uneven ETE mediated by the biodegradable MgR induced a comprehensive immunologic activation in the OS tumor microenvironment (TME), which would inspire the application of MHT for the effective treatment of OS.

8.
Angew Chem Int Ed Engl ; 62(9): e202215467, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36591974

RESUMO

Oxygen-deficient molybdenum oxide (MoOX ) nanomaterials are prepared as novel nanosensitizers and TME-stimulants for ultrasound (US)-enhanced cancer metalloimmunotherapy. After PEGylation, MoOX -PEG exhibits efficient capability for US-triggered reactive oxygen species (ROS) generation and glutathione (GSH) depletion. Under US irradiation, MoOX -PEG generates a massive amount of ROS to induce cancer cell damage and immunogenic cell death (ICD), which can effectively suppress tumor growth. More importantly, MoOX -PEG itself further stimulates the maturation of dendritic cells (DCs) and triggeres the activation of the cGAS-STING pathway to enhance the immunological effect. Due to the robust ICD induced by SDT and efficient DC maturation stimulated by MoOX -PEG, the combination treatment of MoOX -triggered SDT and aCTLA-4 further amplifies antitumor therapy, inhibits cancer metastases, and elicits robust immune responses to effectively defeat abscopal tumors.


Assuntos
Neoplasias , Óxidos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Molibdênio , Neoplasias/tratamento farmacológico , Hipóxia , Oxigênio/metabolismo , Linhagem Celular Tumoral
9.
Front Pharmacol ; 13: 952804, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160382

RESUMO

Background: Previous studies have suggested that proton pump inhibitors could impair the antiplatelet effect of clopidogrel. It is uncertain whether ilaprazole affects the antiplatelet effect of clopidogrel. This study aimed to determine the drug-drug interaction between ilaprazole and clopidogrel. Methods: A randomized crossover trial of 40 healthy subjects was performed. Clopidogrel was administered alone or in combination with ilaprazole for 7 days. The maximal platelet aggregation (MPA) to 5 µmol/L adenosine diphosphate was measured by light transmission aggregometry and the platelet reactivity index (PRI) was determined by vasodilator-stimulated phosphoprotein P2Y12 assay. High on-treatment platelet reactivity (HOPR) was defined as a MPA of >40%. The inhibition of platelet aggregation (IPA) and PRI in the two phases were compared between two regimens after the last dosing. Results: IPA was comparable between the two regimens at 0, 10 and 24 h (p > 0.05), but higher at 4 h in the clopidogrel alone regimen compared with that in the combined treatment regimen (75.66 ± 18.44% vs. 70.18 ± 17.67%, p = 0.031). The inhibition of PRI was comparable between the two regimens at 0 and 24 h. There were no significant differences in the area under the time-IPA% curve (AUC) or the incidence of HOPR at all time-points between the two regimens. Conclusion: In healthy subjects, ilaprazole has limited effect on the pharmacodynamics of clopidogrel and it may not be clinically relevant. Clinical Trial Registration: [www.chictr.org.cn], identifier [ChiCTR2000031482].

10.
Angew Chem Int Ed Engl ; 61(39): e202208849, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-35929496

RESUMO

Multiple amplification of tumor oxidative stress has been demonstrated as efficient strategy to enhance the reactive oxygen species (ROS)-mediated cancer therapy. Herein, vanadium-based nanocatalysts, hydrogen vanadium bronzes (HX V2 O5 , for short HVO), were constructed and employed as novel biocatalysts for amplifying tumor oxidative stress and enhancing cancer catalytic therapy. Such HVO nanocatalysts harboring multivalent V element possessed multi-functional catalytic activity in decomposing H2 O2 into ⋅OH and depleting endogenous glutathione (GSH) to dually amplify tumor oxidative stress. Meanwhile, HVO nanocatalysts could also be activated by ultrasound to further triply amplify oxidative stress. The massive intracellular ROS caused mitochondrial dysfunction, DNA damage, cell cycle arrest, and cell proliferation inhibition, further realizing cancer cell death and tumor growth inhibition. Collectively, HVO nanocatalysts highlight the remarkable value of ROS-mediated cancer therapies.


Assuntos
Neoplasias , Vanádio , Linhagem Celular Tumoral , Glutationa/metabolismo , Humanos , Hidrogênio , Neoplasias/terapia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
11.
Environ Sci Pollut Res Int ; 29(11): 16193-16202, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34643868

RESUMO

Many studies have reported high arsenic concentrations in the groundwater and soil of the Jianghan Plain (JHP), an important rice production base in China. However, no comprehensive study on the occurrence and risk of As in groundwater-soil-rice systems in this region has been conducted. In this study, As concentrations in groundwater, soil, rice straw, and rice grain samples were analyzed. Arsenic concentrations were found to range from BDL to 42.88 µg/L (median 0.34 µg/L) in phreatic water, BDL to 41.77 µg/L (median 8.64 µg/L) in soil pore water, 10.20 to 21.90 mg/kg (mean 16.52 mg/kg) in soil, 0.204 to 2.860 mg/kg (mean 0.847 mg/kg) in rice straw, and 0.131 to 0.951 mg/kg (mean 0.449 mg/kg) in rice grain. Arsenic uptake by rice from soils was evaluated according to bioavailable As defined by chemical extraction and diffusive gradients in thin films. The results indicated that owing to the low content of highly mobile As fractions, the less mobile As fraction (mainly bound with amorphous Fe/Al (hydr)oxides) also contributed to bioavailable As, suggesting that amorphous Fe/Al bound As should be considered in analyzing bioavailable As. In terms of the geoaccumulation index and the Chinese paddy soil standard (GB15618-2018) limit (25 mg/kg), As pollution in water and soils in the study area is at a low level and can be considered relatively safe. However, the target hazard quotients and cancer risk assessment indicated that As pollution is at a dangerous level with potential human health risk. According to the bioconcentration factor, the bioavailability of soil is higher in JHP compared with other rice-growing areas owing to the unique hydrogeological conditions and irrigation using groundwater with high As content. Rice planting areas in JHP should be set as far away from large rivers as possible, and groundwater with high As concentrations must be pre-treated prior to irrigation.


Assuntos
Arsênio , Água Subterrânea , Oryza , Poluentes do Solo , Poluentes Químicos da Água , Arsênio/análise , Disponibilidade Biológica , China , Humanos , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes Químicos da Água/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-33141664

RESUMO

The delay-and-sum (DAS) beamformer is the most commonly used method in medical ultrasound imaging. Compared with the DAS beamformer, the minimum variance (MV) beamformer has an excellent ability to improve lateral resolution by minimizing the output of interference and noise power. However, it is hard to overcome the tradeoff between satisfactory lateral resolution and speckle preservation performance due to the fixed subarray length of covariance matrix estimation. In this study, a new approach for MV beamforming with adaptive spatial smoothing is developed to address this problem. In the new approach, the generalized coherence factor (GCF) is used as a local coherence detection tool to adaptively determine the subarray length for spatial smoothing, which is called adaptive spatial-smoothed MV (AMV). Furthermore, another adaptive regional weighting strategy based on the local signal-to-noise ratio (SNR) and GCF is devised for AMV to enhance the image contrast, which is called GCF regional weighted AMV (GAMV). To evaluate the performance of the proposed methods, we compare them with the standard MV by conducting the simulation, in vitro experiment, and the in vivo rat mammary tumor study. The results show that the proposed methods outperform MV in speckle preservation without an appreciable loss in lateral resolution. Moreover, GAMV offers excellent performance in image contrast. In particular, AMV can achieve maximal improvements of speckle signal-to-noise ratio (SNR) by 96.19% (simulation) and 62.82% (in vitro) compared with MV. GAMV achieves improvements of contrast-to-noise ratio by 27.16% (simulation) and 47.47% (in vitro) compared with GCF. Meanwhile, the losses in lateral resolution of AMV are 0.01 mm (simulation) and 0.17 mm (in vitro) compared with MV. Overall, this indicates that the proposed methods can effectively address the inherent limitation of the standard MV in order to improve the image quality.


Assuntos
Algoritmos , Processamento de Sinais Assistido por Computador , Animais , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Ratos , Razão Sinal-Ruído , Ultrassonografia
13.
Comput Biol Med ; 116: 103522, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31739004

RESUMO

Coherence-based weighting techniques have been widely studied to weight beamsummed data to improve image quality in ultrasound imaging. Although generalized coherence factor (GCF) enhances the robustness of coherence factor (CF) with preserved speckle pattern by including some incoherent components, the side lobe suppression performance is insufficient due to constant cut-off frequency M0. To address this problem, we introduced in this paper a dynamic GCF method, referred to as DGCF-C, based on the amplitude standard deviation and the convolution output of aperture data. The cut-off frequency is adaptively selected for GCF at each imaging point using the amplitude standard deviation of aperture data. Moreover, the convolution output of aperture data is used to calculate the dynamic GCF. The proposed method is evaluated in simulation and tissue-mimicking phantom studies. The image quality was analyzed in terms of resolution, contrast ratio (CR), generalized contrast-to-noise ratio (GCNR), speckle signal-to-noise ratio (sSNR), and signal-to-noise ratio (SNR). The results demonstrate that DGCF-C (Mmax=2) achieves mean resolution improvements of 35.1% in simulation, and 32.6% in experiment, compared with GCF (M0=1). Moreover, DGCF-C (Mmax=4) outperforms GCF (M0=2) with an average GCNR improvement of 13.5% and an average sSNR improvement of 15.2%, which indicates the better-preservation of speckle.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Ultrassonografia/métodos , Algoritmos , Simulação por Computador , Cistos/diagnóstico por imagem , Humanos , Modelos Biológicos , Imagens de Fantasmas
14.
Artigo em Chinês | MEDLINE | ID: mdl-21619851

RESUMO

OBJECTIVE: Headspace solid-phase microextraction (HS-SPME) was used pre-concentration procedure for the determination of tetrahydrofuran in urine by gas chromatography with hydrogen flame detector. METHODS: Several parameters controlling SPME was studied and optimised: SPME fiber, extraction time and extraction temperature, desorption time and desorption temperature. RESULTS: Under optimal conditions, the correlation coefficient was 0.9998 and good recoveries (range from 93.0% ∼ 100.8%) were achieved, the detection limit was 0.5 µg/L. CONCLUSION: The method can be applied to the determination of trace amount of tetrahydrofuran in urine.


Assuntos
Cromatografia Gasosa/métodos , Furanos/urina , Exposição Ocupacional/análise , Microextração em Fase Sólida/métodos , Humanos
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 41(4): 459-62, 2009 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-19727239

RESUMO

OBJECTIVE: To summarize the improvement of various muscle staining techniques and discuss their application in diagnosis of neuromuscular diseases. METHODS: Three hundred cases of skeletal muscle biopsy samples were examined by histopathological methods. The flash-freezing techniques were used for the preparation of frozen section, which were stained with HE, Gomori trichromic (GMR), glycogen (PAS), and fat acid (oil red O); the enzyme histochemical staining with myosin adenosine triphosphatase (ATPase), and NADH-TR. Those stained methods had been improved. The immunohistochemical staining with dystrophin; and transmission electronic microscopy were used. RESULTS: Deepfreeze with heteropentane-liquid nitrogen and flash-freezing techniques could avoid artifacts of ice crystal vacuolation. GMR staining mainly showed the degenerative and necrotic lesions of mitochondria and muscle fibers. Oil red O staining showed the increase of lipid in muscle fibers. PAS staining mainly showed glycogen and glycoprotein. Application of frozen sections in muscular tissue was better than that of paraffin sections. NADH-TR staining and ATPase staining could distinguish the two types of muscle fibers, and show the changes of inner structure of muscle fibers and mitochondria enzymes. CONCLUSION: The distribution and characteristic pathological changes of the two types of muscle fibers can be showed clearly by enzyme and non-enzyme histochemical staining techniques of the skeletal muscle. These methods can compliment with each other. Only after understanding the technical principles can we master and apply these methods.


Assuntos
Biópsia , Crioultramicrotomia/métodos , Músculo Esquelético/patologia , Coloração e Rotulagem/métodos , Humanos , Doenças Neuromusculares/patologia
16.
J Neurooncol ; 84(3): 263-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17453147

RESUMO

Medulloblastomas (MBs) are the most common malignant brain tumors of childhood. Antitumor agents promoting long-term survival with limited toxicities are thus far lacking. Preliminary findings suggest that retinoic acid (RA) derivatives (retinoids) exert antitumor effects by inhibiting cell proliferation and inducing cell differentiation, apoptosis, and growth arrest, and RAs have been specifically shown to induce apoptosis in some MB cells. However, there is no conclusive evidence of retinoids inducing cell growth arrest in MBs. The aim of this study is to investigate whether retinoids play a role in cell-cycle arrest of MB cells. All-trans-retinoic acid (ATRA) was selected for these studies as it is known to have the capacity of inducing cell cycle arrest and apoptosis in other types of cancer cells. Three MB cell lines (DAOY, D283 and D341) were subjected to ATRA treatment. The proportions of cells in the G0/G1 phase of cell cycle and in apoptosis were evaluated. The results showed that cell growth arrest, rather than apoptosis, was the main mechanism by which RA inhibited cell proliferation in the MB cell line DAOY, but not in the others (D283 and D341). Decreased expression of CyclinD1 and C-myc which regulate the transition of cell cycle was observed in DAOY cells following drug treatment, suggesting that these genes might be involved in ATRA retardation of cell cycle progression. Expression of RARbeta, a mediator of the action of retinoids, was also induced by RA in DAOY cells, implying that RAR-beta might also be involved in the mechanism of RA-induced cell cycle arrest. In conclusion, we have provided evidence for the first time that RA may induce cell cycle arrest in vitro in DAOY MB cells via inhibition of CyclinD1 or C-myc.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Cerebelares/metabolismo , Meduloblastoma/metabolismo , Tretinoína/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Cerebelares/patologia , Ciclina D1/efeitos dos fármacos , Humanos , Meduloblastoma/patologia , Proteínas Proto-Oncogênicas c-myc/efeitos dos fármacos , Receptores do Ácido Retinoico/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Zhonghua Bing Li Xue Za Zhi ; 35(1): 29-31, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16608646

RESUMO

OBJECTIVE: To study the clinicopathological features and differential diagnoses of mixed epithelial and stromal tumor of the kidney. METHODS: Clinical and pathological characteristics of 4 cases of mixed epithelial and stromal tumor of the kidney were studied. RESULTS: Three patients were female and one was male. All patients presented with flank pain and hematuria. Radiologic studies revealed cystic and solid masses involving the kidney. Grossly the tumors had a solid and cyst appearance. Microscopically, the tumors were composed of a mixture of stromal and epithelial elements. The epithelial elements were variable in cell types including cuboidal, hobnail and columnar cells. One case showed Müllerian and intestinal epithelial differentiations. Stromal elements essentially consisted of spindle cells, with thick-walled blood vessels and bands of smooth muscle cells as distinctive features of the tumor. Immunohistochemical staining revealed that the epithelial components were positive for AE1/AE3, whereas the stromal components were positive for ER, PR, and SMA. All patients underwent nephrectomy and were well without evidence of recurrence. CONCLUSIONS: Mixed epithelial and stromal tumor of the kidney is a benign neoplasm with distinct histopathological features. It should be distinguished from many other renal neoplasms. Surgical intervention is a preferred therapy.


Assuntos
Neoplasias Renais/patologia , Neoplasias Complexas Mistas/patologia , Neoplasias Epiteliais e Glandulares/patologia , Actinas/metabolismo , Adulto , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Músculo Liso/metabolismo , Neoplasias Complexas Mistas/metabolismo , Neoplasias Complexas Mistas/cirurgia , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/cirurgia , Nefrectomia/métodos , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
19.
Zhonghua Bing Li Xue Za Zhi ; 34(7): 385-8, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16251038

RESUMO

OBJECTIVE: To study the morphologic changes of collagen type III glomerulopathy and to investigate the possible cellular origin for collagen III production. METHODS: Light microscopy, immunofluorescent staining, immunohistochemistry (for collagen I, III and IV and alpha-SMA) and electron microscopy studies on 3 renal biopsy cases of collagen type III glomerulopathy were performed. RESULTS: Two cases presented with nephrotic syndrome, one of which was associated with systemic hypertension. The third case showed renal impairment and renal hypertension. None had any known family history of renal diseases. Light microscopy showed diffuse thickened glomerular basement membrane and expanded mesangium with deposition of weakly PAS-positive homogeneous material not associated with mesangial cell proliferation. Electron microscopy revealed massive collagen fiber deposits in the subendothelial spaces and mesangium. The mesangial cells also contained bundles of microfilaments in the subplasmalemmal regions. Immunohistochemically, the diffuse positivity for type III collagen corresponded to the homogeneous material seen under light microscopy. The staining for type I and IV collagens was negative. Alpha-SMA was expressed in many mesangial cells. CONCLUSIONS: The diagnosis of collagen type III glomerulopathy can be made on the basis of detailed morphologic examination and ancillary investigations. It is possible that activated mesangial cells may be the cellular origin of collagen III.


Assuntos
Colágeno Tipo III/metabolismo , Glomerulonefrite/patologia , Actinas/metabolismo , Adulto , Feminino , Membrana Basal Glomerular/patologia , Membrana Basal Glomerular/ultraestrutura , Glomerulonefrite/metabolismo , Humanos , Masculino , Células Mesangiais/metabolismo , Células Mesangiais/patologia , Pessoa de Meia-Idade
20.
Zhonghua Bing Li Xue Za Zhi ; 34(7): 393-6, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16251041

RESUMO

OBJECTIVE: To detect the expression of macrophage inflammatory protein-1alpha (MIP-1alpha), a disintegrin-like and metalloproteinase (ADAM) 8 and 12 and CD68 protein in giant cell lesions of jaw and giant cell tumors of long bone, and to study their effects on the histogenesis of giant cells in such lesions. METHODS: MIP-1alpha, ADAM8, ADAM12 and CD68 were detected by immunohistochemistry in 24 paraffin-embedded specimens of central giant cell lesions of jaw and giant cell tumors respectively. RESULTS: MIP-1alpha positive signal was located in blood vessels and bone. ADAM8, ADAM12 and CD68 positive signals were located in the cell membrane and cytoplasm of all multinucleated giant cells and some round mononuclear cells in the lesions. In addition, some spindle mononuclear stromal cells were positive for ADAM12 in both lesions. CONCLUSION: Multinucleated giant cells probably originate from CD68-postive round mononuclear cells, which are recruited from monocyte-macrophage system by chemokines, such as MIP-1alpha, followed by cell fusion mediated by ADAM8 and ADAM12.


Assuntos
Proteínas ADAM/metabolismo , Neoplasias Ósseas/metabolismo , Tumor de Células Gigantes do Osso/metabolismo , Granuloma de Células Gigantes/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , Proteínas de Membrana/metabolismo , Proteína ADAM12 , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Neoplasias Ósseas/patologia , Membrana Celular/metabolismo , Quimiocina CCL3 , Quimiocina CCL4 , Citoplasma/metabolismo , Tumor de Células Gigantes do Osso/patologia , Células Gigantes/metabolismo , Granuloma de Células Gigantes/patologia , Humanos , Doenças Maxilomandibulares/metabolismo , Doenças Maxilomandibulares/patologia
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