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1.
J Acoust Soc Am ; 149(6): 4180, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34241472

RESUMO

Large-scale cell suspension culture technology opens up opportunities for numerous medical and bioengineering applications. For these purposes, scale-up of the culture system is paramount. For initial small-scale culture, a simple static suspension culture (SSC) is generally employed. However, cell sedimentation due to the lack of agitation limits the culture volume feasible for SSC. Thus, when scaling up, cell suspensions must be manually transferred from the culture flask to another vessel suitable for agitation, which increases the risk of contamination and human error. Ideally, the number of culture transfer steps should be kept to a minimum. The present study describes the fabrication of an ultrasonic suspension culture system that stirs cell suspensions with the use of acoustic streaming generated by ultrasound irradiation at a MHz frequency. This system was applied to 100-mL suspension cultures of Chinese hamster ovary cells-a volume ten-fold larger than that generally used. The cell proliferation rate in this system was 1.88/day when applying an input voltage of 40 V to the ultrasonic transducer, while that of the SSC was 1.14/day. Hence, the proposed method can extend the volume limit of static cell suspension cultures, thereby reducing the number of cell culture transfer steps.


Assuntos
Acústica , Técnicas de Cultura de Células , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Suspensões
2.
Nano Lett ; 11(2): 361-4, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21204550

RESUMO

Herein we demonstrate the extra-low-temperature oxygen storage capacity (OSC) of cerium oxide nanocrystals with cubic (100) facets. A considerable OSC occurs at 150 °C without active species loading. This temperature is 250 °C lower than that of irregularly shaped cerium oxide. This result indicates that cubic (100) facets of cerium oxide have the characteristics to be a superior low-temperature catalyst.


Assuntos
Cério/química , Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Oxigênio/química , Oxigênio/isolamento & purificação , Temperatura Baixa , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
3.
Ultrason Sonochem ; 73: 105488, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33607592

RESUMO

Suspension culture is an essential large-scale cell culture technique for biopharmaceutical development and regenerative medicine. To transition from monolayer culture on the culture surface of a flask to suspension culture in a bioreactor, a pre-specified cell number must first be reached. During this period of preparation for suspension culture, static suspension culture in a flask is generally performed because the medium volume is not large enough to use a paddle to circulate the medium. However, drawbacks to this static method include cell sedimentation, leading to high cell density near the bottom and resulting in oxygen and nutrient deficiencies. Here, we propose a suspension culture method with acoustic streaming induced by ultrasonic waves in a T-flask to create a more homogeneous distribution of oxygen, nutrients, and waste products during the preparation period preceding large-scale suspension culture in a bioreactor. To demonstrate the performance of the ultrasonic method, Chinese hamster ovary cells were cultured for 72 h. Results showed that, on average, the cell proliferation was improved by 40% compared with the static method. Thus, the culture time required to achieve a 1000-fold increase could be reduced by 32 h (a 14% reduction) compared with the static method. Furthermore, the ultrasonic irradiation did not compromise the metabolic activity of the cells cultured using the ultrasonic method. These results demonstrate the effectiveness of the ultrasonic method for accelerating the transition to large-scale suspension culture.


Assuntos
Técnicas de Cultura de Células/métodos , Sonicação/métodos , Acústica , Animais , Reatores Biológicos , Células CHO , Proliferação de Células , Cricetulus
4.
Hum Reprod ; 23(4): 944-51, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18281245

RESUMO

BACKGROUND: A recent clinical trial demonstrated that selective progesterone receptor modulator asoprisnil is effective in reducing uterine leiomyoma volume. We investigated the effects of asoprisnil in vitro on the expression of the extracellular matrix (ECM)-remodeling enzymes and collagens in cultured leiomyoma and matching normal myometrial cells. METHODS: The expression of extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), tissue inhibitors of MMP (TIMPs) and collagens were assessed by western blot analysis. RESULTS: Untreated cultured leiomyoma cells had significantly lower EMMPRIN (P < 0.05), MMP-1 (P < 0.05) and membrane type 1-MMP (MT1-MMP) (P < 0.01) protein contents, but significantly higher TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.05) and type III (P < 0.01) collagen protein contents compared with untreated cultured myometrial cells. Treatment with asoprisnil at concentrations > or =10(-7) M for 48 h significantly (P < 0.05) increased EMMPRIN, MMP-1 and MT1-MMP protein contents, and decreased TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.01) and type III (P < 0.05 at 10(-7) M; P < 0.01 at 10(-6) M) collagen protein contents in cultured leiomyoma cells compared with control cultures. However, asoprisnil treatment did not affect the protein contents of ECM-remodeling enzymes and collagens in cultured myometrial cells. CONCLUSIONS: These results suggest that asoprisnil may reduce collagen deposit in the ECM of cultured leiomyoma cells through decreasing collagen synthesis and enhancing the expression of EMMPRIN, MMPs and TIMPs without comparable effects on cultured myometrial cells.


Assuntos
Basigina/metabolismo , Colágeno/biossíntese , Estrenos/farmacologia , Oximas/farmacologia , Receptores de Progesterona/efeitos dos fármacos , Adulto , Células Cultivadas , Colágeno/efeitos dos fármacos , Regulação para Baixo , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Técnicas In Vitro , Leiomioma/tratamento farmacológico , Leiomioma/metabolismo , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Miométrio/efeitos dos fármacos , Inibidores Teciduais de Metaloproteinases/metabolismo , Regulação para Cima , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/metabolismo
5.
Chem Commun (Camb) ; 54(28): 3528-3531, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29565429

RESUMO

Herein, we report on the synthesis of Ce0.5Zr0.5-xTixO2 oxygen storage materials prepared via a solution combustion method. Ce0.5Zr0.4Ti0.1O2 showed an outstanding oxygen storage capacity (1310 µmol-O per g) at 200 °C compared to conventional κ-Ce2Zr2O8 (650 µmol-O per g) due to its cation ordering and the formation of weakly bound oxygen atoms induced by Ti substitution.

6.
ACS Omega ; 3(6): 6560-6565, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458832

RESUMO

Monodisperse ceria-zirconia nanoparticles have attracted much attention as potential high-performance catalysts. Acidic aqueous solutions are generally used for peptizing aggregated precipitates during the fabrication of disperse nanoparticles. However, the peptization process requires multiple hours of aging, which significantly decreases the production efficiency. Hence, various researchers have attempted to eliminate this stage altogether by performing a coprecipitation process under ambient conditions using common salts as the starting materials. In this work, we report a continuous and direct technique for the fabrication of monodisperse composite oxide nanoparticles via coprecipitation inside a novel high-shear agitation reactor without aging. Using this method, monodisperse ceria-zirconia-yttria composite oxide nanoparticles with diameters of 3 nm were successfully synthesized.

7.
J Clin Endocrinol Metab ; 91(4): 1296-304, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16464945

RESUMO

CONTEXT: Asoprisnil, a selective progesterone (P4) receptor (PR) modulator (SPRM) with mixed P4 agonist/antagonist activities, reduces uterine leiomyoma volume in a dose-dependent manner in the presence of follicular phase estrogen concentrations. The evidence from clinical studies suggests that asoprisnil may directly target the uterine leiomyomata. OBJECTIVE AND METHODS: The present study evaluated the effects of asoprisnil on cell proliferation, the expression of apoptosis-related proteins, and apoptosis in cultured human uterine leiomyoma cells and matched normal myometrial cells. PR-A and PR-B expression in the two types of cells was comparatively evaluated. Cell proliferation, proliferating cell nuclear antigen (PCNA)-positive rate, and TUNEL-positive rate were assessed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay, immunocytochemistry, and terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling (TUNEL) assay, respectively. The expression of apoptosis-related proteins and PR was assessed by Western blot analysis. RESULTS: Compared with untreated cultures, asoprisnil decreased the number of viable cultured cells, the PCNA-positive rate, and PCNA protein expression in cultured leiomyoma cells. Asoprisnil increased the TUNEL-positive rate, cleaved caspase-3, and cleaved poly(adenosine 5'-diphosphate-ribose) polymerase expression and decreased Bcl-2 protein expression in cultured leiomyoma cells. These effects were dose and time dependent. In cultured myometrial cells, however, asoprisnil did not affect cell proliferation and apoptosis. PR-B expression was elevated in cultured leiomyoma cells compared with cultured myometrial cells, whereas no differences in PR-A expression were noted between the two cell types. CONCLUSIONS: These results show that asoprisnil inhibits proliferation and induces apoptosis in cultured uterine leiomyoma cells in the absence of comparable effects on cultured normal myometrial cells, suggesting a cell type-specific effect.


Assuntos
Apoptose/efeitos dos fármacos , Estrenos/farmacologia , Leiomioma/patologia , Miométrio/patologia , Oximas/farmacologia , Receptores de Progesterona/efeitos dos fármacos , Neoplasias Uterinas/patologia , Western Blotting , Caspase 3 , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Genes bcl-2/genética , Humanos , Marcação In Situ das Extremidades Cortadas , Poli(ADP-Ribose) Polimerases/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo
8.
Semin Reprod Med ; 28(3): 260-73, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20414849

RESUMO

Although the traditional concept supports a crucial role of estrogen in promoting leiomyoma growth, unequivocal evidence has emerged indicating that progesterone also plays a vital role in the regulation of leiomyoma growth. Recent clinical trials have demonstrated the efficacy of asoprisnil, a selective progesterone receptor modulator, and CDB-2914, a novel progesterone receptor modulator, for the treatment of women with symptomatic leiomyomata. These compounds significantly reduced leiomyoma and uterine volume and improved leiomyoma-related symptoms without serious complications. However, the precise mechanism whereby these compounds cause leiomyoma regression remains poorly understood. Our extensive in vitro studies have provided novel evidence for the growth inhibitory effects of asoprisnil and CDB-2914 on cultured leiomyoma cells. Both compounds exhibited antiproliferative, proapoptotic, and antifibrotic actions on cultured leiomyoma cells in the absence of comparable effects on cultured normal myometrial cells. Asoprisnil and/or CDB-2914 modulated the ratio of progesterone receptor isoforms (PR-A and PR-B) in cultured leiomyoma cells; decreased the cell viability; suppressed the expression of growth factors, angiogenic factors, and their receptors in those cells; and induced apoptosis through activating the mitochondrial and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) pathways and eliciting endoplasmic reticulum stress. Furthermore, these compounds suppressed types I and III collagen synthesis by modulating extracellular matrix-remodeling enzymes in cultured leiomyoma cells without affecting those syntheses in cultured normal myometrial cells. These findings indicate that both compounds exert antiproliferative, proapoptotic, and antifibrotic actions on leiomyoma cells in a cell-type specific manner. This supports the notion that asoprisnil and CDB-2914 hold promise for the nonsurgical treatment of uterine leiomyomata.


Assuntos
Estrenos/uso terapêutico , Leiomioma/tratamento farmacológico , Leiomioma/patologia , Norpregnadienos/uso terapêutico , Oximas/uso terapêutico , Receptores de Progesterona/metabolismo , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/patologia , Inibidores da Angiogênese/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Estrenos/farmacologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Feminino , Humanos , Leiomioma/metabolismo , Miométrio/efeitos dos fármacos , Norpregnadienos/farmacologia , Oximas/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptores de Progesterona/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Neoplasias Uterinas/metabolismo
9.
Reprod Sci ; 14(8 Suppl): 20-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089606

RESUMO

Progesterone plays a pivotal role in controlling uterine leiomyoma growth. The authors review studies they conducted to evaluate the comparative effects of asoprisnil on proliferation, apoptosis, and growth factor expression in cultured leiomyoma and normal myometrial cells. Treatment with asoprisnil decreased the proliferating cell nuclear antigen-positive rate and the number of viable cells and increased the terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling- positive rate in cultured leiomyoma cells in a dose-dependent manner ( P < .05). Similarly, asoprisnil decreased Bcl-2 expression and increased cleaved caspase-3 and cleaved poly(adenosine 5'-diphosphate-ribose) polymerase in leiomyoma cells but not in normal myometrial cells. Similarly, asoprisnil decreased epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), and transforming growth factor (TGF) beta mRNA and protein expression, as well as EGF receptor, IGF-IR alpha, and TGF RII protein expression in leiomyoma cells but not in cultured normal myometrial cells. These results suggest that asoprisnil selectively inhibits proliferation by downregulating the growth factors and their receptor expression and induces apoptosis in leiomyoma cells without affecting proliferation and apoptosis in normal myometrial cells.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estrenos/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Leiomioma/patologia , Miométrio/efeitos dos fármacos , Oximas/farmacologia , Neoplasias Uterinas/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação para Baixo , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/metabolismo , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Leiomioma/metabolismo , Miométrio/metabolismo , Miométrio/patologia , Fosforilação , Progesterona/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/efeitos dos fármacos , Receptor IGF Tipo 1/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Progesterona/efeitos dos fármacos , Receptores de Progesterona/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/efeitos dos fármacos , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fatores de Tempo , Fator de Crescimento Transformador beta3/metabolismo , Células Tumorais Cultivadas , Neoplasias Uterinas/metabolismo
10.
Hum Reprod ; 21(7): 1869-77, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16613890

RESUMO

BACKGROUND: This study was conducted to evaluate the effects of a novel selective progesterone receptor modulator (SPRM) asoprisnil on the expression of growth factors and their receptors and on growth factor-induced proliferation of cultured uterine leiomyoma and matching myometrial cells. METHODS: The expression of epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I) and transforming growth factor (TGFbeta3) was assessed by immunocytochemistry and semi-quantitative RT-PCR. The expression of phosphorylated EGF receptor (p-EGFR), IGF-I receptor alpha subunit (IGF-IRalpha) and phosphorylated TGFbeta receptor type II (p-TGFbeta RII) was assessed by Western blot analysis. Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. RESULTS: Treatment with 10(-7) M asoprisnil decreased EGF, IGF-I and TGFbeta3 mRNA and protein expression as well as p-EGFR, IGF-IRalpha and p-TGFbeta RII protein expression in leiomyoma cells cultured for 72 h. EGF (100 ng/ml), IGF-I (100 ng/ml) and TGFbeta3 (10 ng/ml) increased the number of viable leiomyoma cells cultured for 72 h, whereas the concomitant treatment with 10(-7) M asoprisnil antagonized the growth factor-induced increase in leiomyoma cell proliferation. In cultured myometrial cells, however, asoprisnil affected neither the growth factor and their receptor expression nor the cell proliferation. CONCLUSION: Asoprisnil inhibits the expression of EGF, IGF-I, TGFbeta3 and their receptors in cultured leiomyoma cells without affecting their expressions in myometrial cells.


Assuntos
Fator de Crescimento Epidérmico/biossíntese , Estrenos/farmacologia , Fator de Crescimento Insulin-Like I/biossíntese , Leiomioma/metabolismo , Oximas/farmacologia , Receptores de Fatores de Crescimento/biossíntese , Receptores de Progesterona/efeitos dos fármacos , Fator de Crescimento Transformador beta/biossíntese , Neoplasias Uterinas/metabolismo , Adulto , Western Blotting , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo , Receptores ErbB/biossíntese , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Miométrio/citologia , Proteoglicanas/biossíntese , Receptor IGF Tipo 1/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
11.
Hum Reprod ; 21(9): 2408-16, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16720624

RESUMO

BACKGROUND: This study was conducted to evaluate the effects of graded concentrations (10(-8), 10(-7) and 10(-6) M) of progesterone receptor (PR) modulator CDB-2914 on the protein contents of PR, of vascular endothelial growth factor (VEGF), adrenomedullin (ADM) and their receptors in cultured human uterine leiomyoma and matching myometrial cells. METHODS: PR-A, PR-B, VEGF-A, VEGF-B, VEGF receptor (VEGFR)-1, VEGFR-2, ADM and ADM receptor (ADMR) contents were assessed by Western blot analysis. RESULTS: Treatment with 100 ng/ml progesterone increased VEGF-A, VEGF-B and ADM contents in cultured leiomyoma cells and normal myometrial cells. The concomitant treatment with 10(-6) M CDB-2914 significantly decreased the progesterone-induced VEGF-A, VEGF-B and ADM contents in cultured leiomyoma cells but not in normal myometrial cells. CDB-2914 treatment alone decreased VEGFR-1, VEGFR-2 and ADMR contents in cultured leiomyoma cells but not in normal myometrial cells. CDB-2914 treatment increased PR-A and decreased PR-B contents in cultured leiomyoma cells in a dose-dependent manner compared with untreated cultures, whereas no significant changes in PR isoform contents were observed in normal myometrial cells. CONCLUSIONS: These results suggest that CDB-2914 down-regulates VEGF, ADM and their receptor contents and modulates PR isoform contents in cultured leiomyoma cells in a cell-type-specific manner.


Assuntos
Adrenomedulina/biossíntese , Regulação para Baixo , Leiomioma/metabolismo , Norpregnadienos/farmacologia , Receptores de Progesterona/biossíntese , Receptores de Progesterona/metabolismo , Neoplasias Uterinas/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adrenomedulina/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Miométrio/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
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