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1.
J Endourol ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38919128

RESUMO

Purpose: Retrograde intrarenal surgery is the gold-standard treatment for most kidney stones. During ureteroscopy, ureteral access sheath insertion at forces greater than 8.0 Newtons (N) risks high-grade ureteral injury. To monitor force, our institution utilizes a unique, Bluetooth-equipped device (i.e., the University of California-Irvine Force Sensor). Given the unique nature of the force sensor, we sought to develop an inexpensive and accessible force sensor based on Boyle's law and the specific amount of force required to compress an occluded 1.0 mL syringe. Materials and Methods: We evaluated three brands of 1.0 mL syringes. After setting the plunger at 1.0 mL, the syringe was occluded, and the syringe plunger was compressed. The syringe volume was recorded when the applied force on the plunger reached 4.0 N, 6.0 N, and 8.0 N. Multiple trials were performed to assess reliability and reproducibility. A method for applying this clinically was also developed. Results: The precise force thresholds identified for a 1.0 mL Luer-Lok™ Syringe (Becton Dickinson, Franklin Lakes, NJ) were 0.30 mL for 4.00 N, 0.20 mL for 6.00 N, and 0.15 mL for 8.00 N. The 1.0 mL Tuberculin Syringe and 1.0 mL Luer Slip Syringe were less precise, but compression from 1.0 to 0.40 mL, 0.25 mL, and 0.20 mL corresponded to force sensor readings that did not exceed 4.00 N, 6.00 N, and 8.00 N, respectively. Conclusions: Based on volume changes, 4.00 N, 6.00 N, and 8.00 N of force can be reliably and reproducibly achieved using an occluded 1.0 mL syringe.

2.
Front Oncol ; 12: 943846, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912174

RESUMO

We have previously demonstrated the in vivo chemopreventive efficacy of flavokawain A (FKA), a novel chalcone from the kava plant, in prostate carcinogenesis models. However, the mechanisms of the anticarcinogenic effects of FKA remain largely unknown. We evaluated the effect of FKA on prostate tumor spheroid formation by prostate cancer stem cells, which were sorted out from CD44+/CD133+ prostate cancer cells 22Rv1 and DU145. FKA treatment significantly decreased both the size and numbers of the tumor spheroids over different generations of spheroid passages. In addition, the dietary feeding of FKA-formulated food to Nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice bearing CD44+/CD133+ 22Rv1 xenograft tumors resulted in a significant reduction of tumor growth compared to those fed with vehicle control food-fed mice. Furthermore, the expression of stem cell markers, such as Nanog, Oct4, and CD44, were markedly downregulated in both tumor spheroids and tumor tissues. We also observed that FKA inhibits Ubc12 neddylation, c-Myc, and keratin-8 expression in both CD44+/CD133+ prostate tumor spheroids and xenograft tumors. Our results suggest that FKA can reduce the tumor-initiating properties and stemness of prostate cancer, which provides a new mechanism for the chemoprevention efficacy of FKA.

3.
Mol Carcinog ; 59(2): 193-201, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31782573

RESUMO

Gartanin, a 4-prenylated xanthone, has been identified from the purple mangosteen fruit as a potent growth inhibitor of various cancer cell lines, including prostate cancer. However, much of Gartanin's anticancer mechanism remains unknown. We have discovered that Gartanin docked onto the regulatory subunit of the precursor cell-expressed developmentally downregulated 8 (NEDD8)-activating enzyme (NAE) complex and next to the NEDD8 binding complex, which leads to inhibit NEDD8 conjugations to both Cullin1 and Ubc12 in prostate cancer cell lines and Ubc12 NEDDylation in an in vitro assay. The S phase kinase-associated protein (Skp2) and F-box and WD-repeat domain-containing 2 (FBXW2), the NEDD8 family members of E3 ubiqutin ligases, were also downregulated and upregulated by Gartainin, respectively. Knock-down of NEDD8 expression by short harpin (Sh) RNAs blocked or attenuated these effects of Gartainin. Finally, Gartanin demonstrated its ability to inhibit growth of prostate cancer lines via autophagy initiation. Our data support that Gartanin is a naturally occurring NEDDylation inhibitor and deserves further investigation for prostate cancer prevention and treatment.


Assuntos
Autofagia/efeitos dos fármacos , Proteínas F-Box/metabolismo , Proteína NEDD8/antagonistas & inibidores , Neoplasias da Próstata/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Xantonas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Proteínas F-Box/genética , Humanos , Masculino , Proteína NEDD8/metabolismo , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Interferência de RNA
4.
ACS Nano ; 13(6): 6670-6688, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31117376

RESUMO

To dissect therapeutic mechanisms of transplanted stem cells and develop exosome-based nanotherapeutics in treating autoimmune and neurodegenerative diseases, we assessed the effect of exosomes secreted from human mesenchymal stem cells (MSCs) in treating multiple sclerosis using an experimental autoimmune encephalomyelitis (EAE) mouse model. We found that intravenous administration of exosomes produced by MSCs stimulated by IFNγ (IFNγ-Exo) (i) reduced the mean clinical score of EAE mice compared to PBS control, (ii) reduced demyelination, (iii) decreased neuroinflammation, and (iv) upregulated the number of CD4+CD25+FOXP3+ regulatory T cells (Tregs) within the spinal cords of EAE mice. Co-culture of IFNγ-Exo with activated peripheral blood mononuclear cells (PBMCs) cells in vitro reduced PBMC proliferation and levels of pro-inflammatory Th1 and Th17 cytokines including IL-6, IL-12p70, IL-17AF, and IL-22 yet increased levels of immunosuppressive cytokine indoleamine 2,3-dioxygenase. IFNγ-Exo could also induce Tregs in vitro in a murine splenocyte culture, likely mediated by a third-party accessory cell type. Further, IFNγ-Exo characterization by deep RNA sequencing suggested that IFNγ-Exo contains anti-inflammatory RNAs, where their inactivation partially hindered the exosomes potential to induce Tregs. Furthermore, we found that IFNγ-Exo harbors multiple anti-inflammatory and neuroprotective proteins. These results not only shed light on stem cell therapeutic mechanisms but also provide evidence that MSC-derived exosomes can potentially serve as cell-free therapies in creating a tolerogenic immune response to treat autoimmune and central nervous system disorders.


Assuntos
Encefalomielite Autoimune Experimental/terapia , Exossomos/transplante , Transplante de Células-Tronco Mesenquimais/métodos , Animais , Células Cultivadas , Exossomos/metabolismo , Feminino , Humanos , Interferon gama/farmacologia , Interleucinas/genética , Interleucinas/metabolismo , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Linfócitos T Reguladores/imunologia
5.
Cell Commun Signal ; 17(1): 25, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885218

RESUMO

BACKGROUND: Flavokawain B (FKB) has been identified from kava root extracts as a potent apoptosis inducer for inhibiting the growth of various cancer cell lines, including prostate cancer. However, the molecular targets of FKB in prostate cancer cells remain unknown. METHODS: An in vitro NEDD8 Initiation Conjugation Assay was used to evaluate the neddylation inhibitory activity of FKB. Molecular docking and a cellular thermal shift assay were performed to assess the direct interaction between FKB and the NEDD8 activating enzyme (NAE) complex. Protein neddylation, ubiqutination, stability and expression in cells were assessed with immunoprecipitation and Western blotting methods using specific antibodies. Deletion and site specific mutants and siRNAs were used to evaluate deep mechanisms by which FKB induces Skp2 degradation. Cell growth inhibition and apoptosis induction were measured by MTT, ELISA and Western blotting methods. RESULTS: FKB inhibits NEDD8 conjugations to both Cullin1 and Ubc12 in prostate cancer cell lines and Ubc12 neddylation in an in vitro assay. Molecular docking study and a cellular thermal shift assay reveal that FKB interacts with the regulatory subunit (i.e. APP-BP1) of the NAE. In addition, FKB causes Skp2 degradation in an ubiquitin and proteasome dependent manner. Overexpression of dominant-negative cullin1 (1-452), K720R mutant (the neddylation site) Cullin1 or the F-box deleted Skp2 that losses its binding to the Skp1/Cullin1 complex causes the resistance to FKB-induced Skp2 degradation, whereas siRNA knock-down of Cdh1, a known E3 ligase of Skp2 for targeted degradation, didn't attenuate the effect of FKB on Skp2 degradation. These results suggest that degradation of Skp2 by FKB is involved in a functional Cullin1. Furthermore, proteasome inhibitors Bortezomib and MG132 transcriptionally down-regulate the expression of Skp2, and their combinations with FKB result in enhanced inhibitory effects on the growth of prostate cancer cell lines via synergistic down-regulation of Skp2 and up-regulation of p27/Kip1 and p21/WAF1 protein expression. FKB also selectively inhibits the growth of RB deficient cells with high expression of Skp2. CONCLUSION: These findings provide a rationale for further investigating combination of FKB and Bortezomib for treatment of RB deficient, castration-resistant prostate cancer.


Assuntos
Antineoplásicos/farmacologia , Bortezomib/farmacologia , Flavonoides/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Proteínas Quinases Associadas a Fase S/metabolismo , Antígenos CD/metabolismo , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Bortezomib/uso terapêutico , Caderinas/metabolismo , Proliferação de Células/efeitos dos fármacos , Proteínas Culina/metabolismo , Flavonoides/uso terapêutico , Humanos , Leupeptinas/farmacologia , Leupeptinas/uso terapêutico , Masculino , Proteína NEDD8/metabolismo , Células PC-3 , Enzimas Ativadoras de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo
6.
Eur J Med Chem ; 157: 50-61, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30075402

RESUMO

Novel bioactive heterocycles containing a 3,4,5-trimethoxyphenyl fragment as antiproliferative agents by targeting tubulin were synthesized and their preliminary structure activity relationships (SARs) were explored. Among all these chemical agents, 2-(Benzo[d]oxazol-2-ylthio)-N-(4-methoxybenzyl)-N-(3,4,5-trimethoxyphenyl)acetamide (4d) exhibited the potent antiproliferative activity against MGC-803 cells with an IC50 value of 0.45 µM by induction of G2/M pahse arrest and cell apoptosis. In addition, 4d could change the membrane potential (ΔΨ) of the mitochondria against MGC-803 cells. Importantly, 4d acted as a novel tubulin polymerization inhibitor binding to colchicine site with an IC50 value of 3.35 µM.


Assuntos
Antineoplásicos/farmacologia , Compostos Heterocíclicos/farmacologia , Microtúbulos/efeitos dos fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Humanos , Microtúbulos/metabolismo , Modelos Moleculares , Estrutura Molecular , Polimerização/efeitos dos fármacos , Relação Estrutura-Atividade , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
7.
Curr Pharmacol Rep ; 3(6): 384-395, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30393593

RESUMO

PURPOSE OF REVIEW: Rhodiola rosea extracts have been used as a dietary supplement in healthy populations, including athletes, to non-specifically enhance the natural resistance of the body to both physical and behavior stresses for fighting fatigue and depression. We summarize the information with respect to the new pharmacological activities of Rhodiola rosea extracts and its underlying molecular mechanisms in this review article. RECENT FINDINGS: In addition to its multiplex stress-protective activity, Rhodiola rosea extracts have recently demonstrated its anti-aging, anti-inflammation, immunostimulating, DNA repair and anti-cancer effects in different model systems. Molecular mechanisms of Rhodiola rosea extracts's action have been studied mainly along with one of its bioactive compounds, salidroside. Both Rhodiola rosea extracts and salidroside have contrast molecular mechanisms on cancer and normal physiological functions. For cancer, Rhodiola rosea extracts and salidroside inhibit the mTOR pathway and reduce angiogenesis through down-regulation of the expression of HIF-1α/HIF-2α. For normal physiological functions, Rhodiola rosea extracts and salidroside activate the mTOR pathway, stimulate paracrine function and promote neovascularization by inhibiting PHD3 and stabilizing HIF-1α proteins in skeletal muscles. In contrast to many natural compounds, salidroside is water-soluble and highly bioavailable via oral administration and concentrated in urine by kidney excretion. SUMMARY: Rhodiola rosea extracts and salidroside can impose cellular and systemic benefits similar to the effect of positive lifestyle interventions to normal physiological functions and for anti-cancer. The unique pharmacological properties of Rhodiola rosea extracts or salidroside deserve further investigation for cancer chemoprevention, in particular for human urinary bladder cancer.

8.
Biomaterials ; 77: 87-97, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26584349

RESUMO

Systemic administration of mesenchymal stem cells (MSCs) affords the potential to ameliorate the symptoms of Multiple Sclerosis (MS) in both preclinical and clinical studies. However, the efficacy of MSC-based therapy for MS likely depends on the number of cells that home to inflamed tissues and on the controlled production of paracrine and immunomodulatory factors. Previously, we reported that engineered MSCs expressing P-selectin glycoprotein ligand-1 (PSGL-1) and Sialyl-Lewis(x) (SLeX) via mRNA transfection facilitated the targeted delivery of anti-inflammatory cytokine interleukin-10 (IL-10) to inflamed ear. Here, we evaluated whether targeted delivery of MSCs with triple PSGL1/SLeX/IL-10 engineering improves therapeutic outcomes in mouse experimental autoimmune encephalomyelitis (EAE), a murine model for human MS. We found PSGL-1/SLeX mRNA transfection significantly enhanced MSC homing to the inflamed spinal cord. This is consistent with results from in vitro flow chamber assays in which PSGL-1/SleX mRNA transfection significantly increased the percentage of rolling and adherent cells on activated brain microvascular endothelial cells, which mimic the inflamed endothelium of blood brain/spinal cord barrier in EAE. In addition, IL-10-transfected MSCs show significant inhibitory activity on the proliferation of CD4(+) T lymphocytes from EAE mice. In vivo treatment with MSCs engineered with PSGL-1/SLeX/IL-10 in EAE mice exhibited a superior therapeutic function over native (unmodified) MSCs, evidenced by significantly improved myelination and decreased lymphocytes infiltration into the white matter of the spinal cord. Our strategy of targeted delivery of performance-enhanced MSCs could potentially be utilized to increase the effectiveness of MSC-based therapy for MS and other central nervous system (CNS) disorders.


Assuntos
Encefalomielite Autoimune Experimental/terapia , Interleucina-10/biossíntese , Glicoproteínas de Membrana/biossíntese , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Adesão Celular , Movimento Celular , Técnicas de Cocultura , Endotélio Vascular/metabolismo , Vetores Genéticos/genética , Células HL-60 , Humanos , Interleucina-10/genética , Lentivirus/genética , Antígenos CD15/genética , Antígenos CD15/metabolismo , Ativação Linfocitária , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Bainha de Mielina/fisiologia , Ácido N-Acetilneuramínico/metabolismo , Especificidade de Órgãos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/metabolismo , Medula Espinal/patologia , Transfecção
9.
Psychiatr Serv ; 62(1): 12-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21209293

RESUMO

There is public health interest in the identification and treatment of modifiable cardiometabolic risk factors among patients treated with antipsychotic medications. However, best-practice screening recommendations endorsed by multiple medical organizations have not translated into real-world clinical practice. Quality improvement strategies may help to address the gap between policy and implementation. This column describes the successful implementation of a best-practice glucose screening program in a large network of community mental health centers that was based on Six Sigma and diffusion of innovation theory.


Assuntos
Antipsicóticos/efeitos adversos , Benchmarking , Difusão de Inovações , Hiperglicemia/prevenção & controle , Programas de Rastreamento , Melhoria de Qualidade , Adulto , Glicemia , Serviços Comunitários de Saúde Mental , Redes Comunitárias , Humanos , Hiperglicemia/induzido quimicamente , Estados Unidos
10.
AMIA Annu Symp Proc ; : 1062, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17238681

RESUMO

As awareness of medical errors increases, innovative solutions are required to address these errors so that healthcare providers can be proactive rather than reactive. The development of an enterprise-wide voluntary incident reporting application will provide a mechanism to organize and prioritize resources toward correction of processes that could endanger patients.


Assuntos
Erros Médicos/prevenção & controle , Aplicações da Informática Médica , Gestão de Riscos , Humanos , Gestão de Riscos/normas , Interface Usuário-Computador , Vocabulário Controlado
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