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1.
Nanomaterials (Basel) ; 14(7)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38607153

RESUMEN

In recent years, fluoride pollution in water is a problem that has attracted much attention from researchers. The removal of fluoride-containing wastewater by adsorption with metal oxide as an adsorbent is the most common treatment method. Based on this, the effect of the doping ratio of La2O3, Fe2O3, and Al2O3 on the fluoride-removal performance was discussed by constructing a phase diagram. In this study, the adsorption mechanism of nanocrystalline lanthanum oxide terpolymer was investigated by density functional theory calculation and experiment. The optimal pH condition selected in the experiment was three, and the adsorption kinetics of fluoride ions were more consistent with the quasi-second-order kinetic model. The adsorption thermodynamics was more consistent with the Langmuir model. When the La-Fe-Al ternary composite oxides achieved the optimal adsorption efficiency for fluoride ions, the mass synthesis ratio was Al2O3:(Fe2O3:La2O3 = 1:2) = 1:100, resulting in a fluoride ion removal rate of up to 99.78%. Density functional calculations revealed that the La-Fe-Al ternary composite oxides had three important adsorption sites for La, Fe, and Al. Among them, the adsorption capacity for HF was Fe2O3 > La2O3 > Al2O3, and for F- was La2O3 > Al2O3 > Fe2O3. This provided good guidance for designing adsorbents to remove fluoride.

2.
Chemosphere ; 340: 139808, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37591373

RESUMEN

With the continuous development of society, industrialization, and human activities have been producing more and more pollutants. Fluoride discharge is one of the main causes of water pollution. This review summarizes various commonly used and effective fluoride removal technologies, including ion exchange technology, electrochemical technology, coagulation technology, membrane treatment, and adsorption technology, and points out the outstanding advantages of adsorption technology. Various commonly used fluoride removal techniques as well as typical adsorbent materials have been discussed in published papers, however, the relationship between different adsorbent materials and adsorption models has rarely been explored, therefore, this paper categorizes and summarizes the various models involved in static adsorption, dynamic adsorption, and electrosorption fluoride removal processes, such as pseudo-first-order and pseudo-second-order kinetic models, Langmuir and Freundlich isotherm models, Thomas and Clark dynamic adsorption models, including the mathematical equations of the corresponding models and the significance of the models are also comprehensively summarized. Furthermore, this comprehensive discussion delves into the fundamental adsorption mechanisms, quantification of maximum adsorption capacity, evaluation of resistance to anion interference, and assessment of adsorption regeneration performance exhibited by diverse adsorption materials. The selection of the best adsorption model not only predicts the adsorption performance of the adsorbent but also provides a better description and understanding of the details of each part of the adsorption process, which facilitates the adjustment of experimental conditions to optimize the adsorption process. This review may provide some guidance for the development of more cost-effective adsorbent materials and adsorption processes in the future.


Asunto(s)
Contaminantes Ambientales , Fluoruros , Humanos , Aguas Residuales , Adsorción , Tecnología
3.
Immunol Lett ; 240: 31-40, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34600949

RESUMEN

Neuroblastoma (NB) has high morality rates and is the most common malignant tumor found in children. High aggregation of myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment results in immunosuppression and affects therapeutic effectiveness. At present, doxorubicin (DOX) and dopamine (DA) are the specific drugs used to selectively remove or mature MDSCs. The aim of the present study was to explore the feasibility and underlying mechanism of targeting elimination of MDSCs via DOX or DA administration to alleviate tumor immunosuppression in NB. In the present study, a BALB/c tumor-bearing mouse model was established, and mice were grouped into the control, DOX2.5, DOX5 and DA50 mg/kg groups. DOX or DA were injected intravenously on days 7 and 12 after inoculation, following which the parameters related to the signal transducer and activator of transcription (STAT) pathway in MDSCs, the proportion of MDSCs, T cell infiltration, programmed death-1 (PD-1) on the surface of T cells, the number of regulatory T cells (Tregs), polarization of tumor-related macrophages (TAMs) and tumor growth were compared between the groups on days 14, 17 and 23 after inoculation. The results demonstrated that following DOX or DA administration, STAT1/phosphorylated (p)-STAT1 decreased, whereas STAT3/p-STAT3, STAT5/p-STAT5 and STAT6/p-STAT6 increased, which was accompanied by a decrease in the MDSC proportion in each experimental group. Simultaneously, T cell infiltration in tumors was increased, whereas expression of PD-1, the number of Tregs, TAM polarization and tumor growth were inhibited. The most significant findings were observed in the DOX2.5 mg/kg group. To conclude, low dose DOX or DA administration could effectively regulate the STAT pathway to eliminate MDSCs, alleviate immunosuppression and improve the immune response against NB tumor cells.


Asunto(s)
Células Supresoras de Origen Mieloide/inmunología , Neoplasias Experimentales/inmunología , Neuroblastoma/inmunología , Factores de Transcripción STAT/inmunología , Transducción de Señal/inmunología , Microambiente Tumoral/inmunología , Animales , Ratones , Ratones Endogámicos BALB C
4.
Chin Med J (Engl) ; 125(5): 794-800, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22490577

RESUMEN

BACKGROUND: Adoptive transfer of allogeneic tumor-specific T cells often results in severe graft-versus-host disease (GVHD). Here, we sought to maximize graft-versus-tumor and minimize GVHD by using haploidentical T cells in pre-irradiated B16-melanoma bearing mice. METHODS: C57BL/6 mice bearing B16-melanoma tumors were irradiated with 0, 5, or 7 Gy total body irradiation (TBI), or 7 Gy TBI plus bone marrow transplantation. Tumor areas were measured every 3 days to assess the influence of irradiation treatment on tumor regression. B16-melanoma bearing mice were irradiated with 7 Gy TBI; sera and spleens were harvested at days 1, 3, 5, 7, 9, 11, and 13 after irradiation. White blood cell levels were measured and transforming growth factor ß1 (TGF-b1) and interleukin 10 (IL-10) levels in serum were detected using enzyme-linked immunosorbent assay (ELISA) kits. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry were performed to test TGF-b1, IL-10 and Foxp3 mRNA levels and the proportion of CD4+CD25+Foxp3+ T-regulatory cells (Tregs) in spleens. B16-melanoma bearing C57BL/6 mice were irradiated with 7 Gy TBI followed by syngeneic (Syn1/Syn2) or haploidentical (Hap1/Hap2), dendritic cell-induced cytotoxic T lymphocytes (DC-CTLs) treatment, tumor areas and system GVHD were observed every 3 days. Mice were killed 21 days after the DC-CTLs adoptive transfer; histologic analyses of eyes, skin, liver, lungs, and intestine were then performed. RESULTS: Irradiation with 7 Gy TBI on the B16-melanoma-bearing mice did not influence tumor regression compared to the control group; however, it down-regulated the proportion of Tregs in spleens and the TGF-b1 and IL-10 levels in sera and spleens, suggesting inhibition of autoimmunity and intervention of tumor microenvironment. Adoptive transfer of haploidentical DC-CTLs significantly inhibited B16-melanoma growth. GVHD assessment and histology analysis showed no significant difference among the groups. CONCLUSION: Adoptive transfer of haploidentical tumor-specific T cells in irradiation-pretreated B16-melanoma bearing mice preserved antitumor capacity without causing a GVHD response.


Asunto(s)
Melanoma Experimental/terapia , Linfocitos T/inmunología , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Enfermedad Injerto contra Huésped , Inmunoterapia Adoptiva/métodos , Masculino , Melanoma Experimental/metabolismo , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa , Linfocitos T Reguladores/inmunología
5.
Chin Med J (Engl) ; 124(12): 1854-61, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21740845

RESUMEN

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) is usually constitutively activated in a variety of malignancies. It directly contributes to tumorigenesis, invasion, and metastasis. The surgical treatment of breast cancer has made no breakthroughs in terms of treatment effect, in spite of its long history. Current biotherapies bring a note of optimism to breast cancer treatment. To explore the possibility of a siRNA targeted STAT3 blocking treatment for over-activated tumor cells, we evaluated the efficacy of a STAT3 siRNA on human breast cancer cells in vitro and in vivo. METHODS: Three MCF-7 human breast cancer cell lines were tested: control MCF-7 cells, non-specific siRNA transfected MCF-7 cells and STAT3 siRNA transfected MCF-7 cells. Expression of STAT3 in MCF-7 cells was inhibited by RNA interference (RNAi). The STAT3 mRNA and protein levels were detected by semi-quantity RT-PCR and Western blotting. Cell proliferation and apoptosis were determined by MTT method and flow cytometry. The three groups of MCF-7 cells mentioned above were transplanted subcutanuously into nude mice and their tumorgenic ability observed. The STAT3 mRNA and protein levels of the samples from tumors in different groups were determined by semi-quantity RT-PCR and Western blotting and compared. RESULTS: In STAT3 siRNA transfected MCF-7 cells, the expressions (STAT3/ß-actin) of STAT3 mRNA (0.327 ± 0.020) and protein (0.153 ± 0.006) were significantly lower than that in control MCF-7 cells (mRNA 1.093 ± 0.018, protein 1.374 ± 0.022) and non-specific siRNA transfected MCF-7 cells (mRNA 1.035 ± 0.050, protein 1.320 ± 0.033) (P < 0.05). MTT showed that cell proliferation was significantly reduced and the cell growth inhibition ratio in the STAT3-siRNA group was (44.00 ± 5.10)%, significantly higher than that in non-specific siRNA transfected MCF-7 cells ((16.10 ± 1.05)%, P < 0.05). Flow cytometry results showed that more apoptosis was observed in the STAT3-siRNA group. The rate of apoptosis was (14.79 ± 0.22)%, much higher than in control MCF-7 cells (7.06 ± 0.71) and non-specific siRNA transfected MCF-7 cells (8.45 ± 0.43) (P < 0.05). The tumor growth in the STAT3 siRNA transfected MCF-7 cells was significantly slower than in the two control groups. On the 22th day after transplantation the tumor weight ((21.40 ± 10.57) mg) and volume ((41.15 ± 12.17) mm(3)) in the STAT3 siRNA transfected group were significantly lower than in control group (weight (88.60 ± 12.16) mg, volume (118.45 ± 24.68) mm(3)) and non-specific siRNA transfected group (weight (57.20 ± 21.86) mg, volume (101.36 ± 21.90) mm(3)) (P < 0.05). Both the STAT3 mRNA and protein levels in the tumors from the STAT3 siRNA transfected group were significantly lower than in the tumors from the two control groups. CONCLUSIONS: STAT3 siRNA can effectively silence the STAT3 gene in vitro and in vivo, increase cell apoptosis rate and significantly decrease cell proliferation, which inhibits the growth of breast cancer cell in vitro. Tumor growth of xenograft mice is significantly inhibited. The results obtained in vivo are in consistency with those in vitro. STAT3 may be a novel therapeutic target for breast cancer and RNA interference has potential clinical application.


Asunto(s)
Neoplasias Mamarias Experimentales/terapia , ARN Interferente Pequeño/genética , Factor de Transcripción STAT3/antagonistas & inhibidores , Animales , Apoptosis , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Desnudos , Factor de Transcripción STAT3/genética , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 23(11): 1046-9, 2007 Nov.
Artículo en Chino | MEDLINE | ID: mdl-17988589

RESUMEN

AIM: To investigate the effects of thymosin alpha1 (Talpha1) on the differentiation, maturation and function of tumor lysate-pulsed dendritic cells (LyDCs) in vitro, and to study the antitumor effects on tumor models of the nude mice bearing colon cancer in vivo. METHODS: Immature DCs (imDCs) were prepared routinely from human peripheral blood mononuclear cells. The LyDCs were prepared from the imDCs loaded with lysate of HT-29 tumor cell line. The phenotypes of imDCs and LyDCs pre- or post-stimulated by Talpha1 were analyzed by flow cytometry. Autologous T cells were cocultured with LyDCs in the presence or absence of Talpha1 2 days later. IL-12 secretion of LyDCs and IFN-gamma secretion of the activated T cells in the supernatants were measured by ELISA. The in vitro cytotoxicity of antigen specific cytotoxic T lymphocytes (CTLs) induced by LyDCs which were treated with Talpha1 was evaluated by MTT assay. A humanized nude mice model bearing colon cancer was established. The in vivo antitumor activity was evaluated in the humanized nude mice after the treatment with LyDCs plus Talpha1 or LyDCs alone. RESULTS: The expression levels of HLA-DR, CD80, CD86 and CD83 in imDCs and LyDCs were markedly up-regulated after the stimulation with Talpha1 respectively (P<0.01). The levels of IL-12 and IFN-gamma were also significantly increased in the presence of Talpha1 (P<0.05 and P<0.01, respectively). Cytotoxicity induced by LyDCs treated with Talpha1 was significantly enhanced (P<0.01) as compared with LyDCs in vitro. The humanized cellular immunity was successfully established in the nude mice model. On the 58 th day after the inoculation of tumor cells, the inhibitory rate of tumor growth was significantly higher in the group treated with LyDCs plus Talpha1 than that in the group treated with LyDCs alone (60.41% and 37.20%, respectively; P<0.01). CONCLUSION: Talpha1 can induce the functional maturation of DCs and enhance the immune response of CD4+Th1 arm and cytotoxicity induced by LyDCs. Talpha1 has a synergistic antitumor effect. It might be a promising adjuvant candidate for DC-based immunotherapy of gastrointestinal carcinomas.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias del Colon/inmunología , Neoplasias del Colon/patología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Timosina/análogos & derivados , Animales , Extractos Celulares/inmunología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/terapia , Células Dendríticas/metabolismo , Células Dendríticas/patología , Femenino , Humanos , Inmunoterapia , Interferón gamma/metabolismo , Interleucina-12/metabolismo , Ratones , Ratones Desnudos , Linfocitos T Citotóxicos/inmunología , Timalfasina , Timosina/farmacología
7.
Zhonghua Wai Ke Za Zhi ; 44(7): 476-80, 2006 Apr 01.
Artículo en Chino | MEDLINE | ID: mdl-16772085

RESUMEN

OBJECTIVE: To investigate the antitumor effects of cytotoxic T lymphocytes (CTLs) induced by autologous dendritic cells that were inspired by autologous tumor lysates (ATLs-mDCs). METHODS: Primary gastric cancer cells prepared by short-term culture were used as targets. ATLs-mDCs were subjected to activate autologous T cells to generate CTLs. The immunological functions of DCs were evaluated by flow cytometry and by mixed leukocyte response (MLR) assay. The antitumor outcome of tumor antigen specific CTLs was tested by cytotoxicity assay. Concentrations of IL-12 in cultured DCs and INF-gamma in CTLs were measured by ELISA. RESULTS: The expressions of MHC-II, CD80, CD83 and CD86 were significantly up-regulated in ATLs-mDCs, moreover, the ATLs-mDCs obtained the capability of stimulating the proliferation of autologous T cells with high efficiency. The secretion of IL-12 in ATLs-mDCs was significantly higher than that in pure mature DCs (t = 15.47, P < 0.01) and in immature DCs (t = 28.44, P < 0.01). The secretion of INF-gamma in CTLs activated by ATLs-mDCs was significantly higher than that in CTLs by pure mature DCs (t = 4.84, P < 0.05) and in CTLs by immature DCs (t = 13.74, P < 0. 01). The antigen specific cytotoxicity of CTLs induced by ATLs-mDCs was significantly higher against autologous tumor cells [(84 +/- 11)%] than that against two allogeneic tumor cell lines [(19 +/- 7)% and (19 +/- 11)%; t = 54.18 and 56.46, P < 0.01, respectively]. CONCLUSIONS: ATLs-mDCs might mediate the antigen specific CTLs against autologous gastric cancer cells ex vivo with high efficiency.


Asunto(s)
Células Dendríticas/inmunología , Inmunoterapia Adoptiva/métodos , Neoplasias Gástricas/terapia , Linfocitos T Citotóxicos/inmunología , Citotoxicidad Inmunológica , Humanos , Técnicas In Vitro , Interferón gamma/metabolismo , Interleucina-12/metabolismo
8.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 22(1): 92-5, 2006 Jan.
Artículo en Chino | MEDLINE | ID: mdl-16388755

RESUMEN

AIM: To explore the efficiency of antitumor immunity induced by autologous dendritic cells (DCs) transfected with total RNA of autologous gastric cancer cells. METHODS: Short-term cultured primary gastric cancer cells were prepared. DCs in peripheral blood mononuclear cells (PBMCs) from gastric cancer patients were induced with rhGM-CSF, rhIL-4 and TNF-alpha. The mature DCs transfected with total RNA of autologous gastric cancer cells were subjected to activate autologous T cells transforming into CTLs, and the activity of CTLs was detected by using CCK-8 kit. The immunological function of DCs were evaluated by flow cytometry and mixed lymphocyte culture(MLC) assay. The levels of IFN-gamma and IL-12 were detected by ELISA. RESULTS: Mature DCs transfected with total RNA of autologous gastric cancer cells not only highly expressed costimulatory molecules (CD80, CD83 and CD86) and (MHC-I and MHC-II), but also powerfully stimulated allogenic or autologous T cell proliferation. The level of IL-12 secreted by mature DCs transfered with tumor RNA was notably higher than those secreted by untransfered and immature DCs, and the rate of killing autologous gastric cancer cells by CTLs was markedly higher than that of killing allogenic tumor cells. CONCLUSION: Mature DCs transfected with autologous gastric cancer cell total RNA can induce and activate high antigen-specific CTLs directed at autologous gastric cancer cells in vitro.


Asunto(s)
Citotoxicidad Inmunológica/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Inmunoterapia/métodos , ARN/genética , Neoplasias Gástricas/terapia , Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Citotoxicidad Inmunológica/genética , Humanos , Inmunoglobulinas/metabolismo , Interleucina-12/metabolismo , Glicoproteínas de Membrana/metabolismo , Microscopía de Contraste de Fase , Neoplasias Gástricas/genética , Células Tumorales Cultivadas , Antígeno CD83
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