Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37628771

RESUMO

Multiple myeloma (MM) is a cancer of plasma cells in the bone marrow characterized by bone lesions, hypercalcemia, anemia, and renal failure. Bortezomib (BTZ), a common treatment for MM, is a proteasome inhibitor that induces apoptosis in MM cells. However, high doses of BTZ can be very toxic, signifying a need for a synergistic drug combination to improve treatment efficacy. Resveratrol (RES), a phenolic compound found in grapes, has been shown to inhibit MM cell growth. We sought to identify a synergistic combination of BTZ with a RES derivative and analyze the effects on reducing viability and inducing apoptosis in human MM cells. BTZ as well as RES and its derivatives pinostilbene (PIN) and piceatannol (PIC) decreased MM cell viability in a dose- and time-dependent manner and increased expression of cleaved proapoptotic proteins poly(ADP-ribose) polymerase 1 (PARP1) and caspase-3 in a dose-dependent manner. The combination of 5 nM BTZ and 5 µM PIN was identified to have synergistic cytotoxic effects in MM RPMI 8226 cells. MM RPMI 8226 cells treated with this combination for 24 h showed increased cleaved PARP1 and caspase-3 expression and higher percentages of apoptotic cells versus cells treated with the individual compounds alone. The treatment also showed increased apoptosis induction in MM RPMI 8226 cells co-cultured with human bone marrow stromal HS-5 cells in a Transwell model used to mimic the bone marrow microenvironment. Expression of oxidative stress defense proteins (catalase, thioredoxin, and superoxide dismutase) in RPMI 8226 cells were reduced after 24 h treatment, and cytotoxic effects of the treatment were ameliorated by antioxidant N-acetylcysteine (NAC), suggesting the treatment impacts antioxidant levels in RPMI 8226 cells. Our results suggest that this combination of BTZ and PIN decreases MM cell viability synergistically by inducing apoptosis and oxidative stress in MM cells.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Humanos , Bortezomib/farmacologia , Caspase 3 , Mieloma Múltiplo/tratamento farmacológico , Antioxidantes , Resveratrol/farmacologia , Microambiente Tumoral
2.
Soc Psychol Q ; 78(4): 399-411, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27478288

RESUMO

Stereotypes of outgroups help create social identificational boundaries for ingroups. When the ingroup is dominant, members employ individualist sentiments to justify their status. In this study, we build on advances in social psychological research that account for multiple outgroup stereotypes. We argue the Asian American model minority stereotype is analogous to the "cold but competent" position of perceptions toward Asians in Fiske's stereotype content model. Asian Americans are perceived to be exceptional to other minority groups, and we hypothesize that perceived competence is associated with individualist sentiments directed at Blacks and Latinos. Using data from the National Longitudinal Study of Freshmen, we find support for our hypotheses but find that perceived coldness has no relationship to individualist sentiments. We discuss the implications and directions for further research.

3.
Front Pharmacol ; 15: 1325196, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510655

RESUMO

Multiple myeloma (MM) is characterized by the accumulation of malignant plasma cells preferentially in the bone marrow. Currently, emerging chemotherapy drugs with improved biosafety profiles, such as immunomodulatory agents and protease inhibitors, have been used in clinics to treat MM in both initial therapy or maintenance therapy post autologous hematopoietic stem cell transplantation (ASCT). We previously discovered that caffeic acid phenethyl ester (CAPE), a water-insoluble natural compound, inhibited the growth of MM cells by inducing oxidative stress. As part of our continuous effort to pursue a less toxic yet more effective therapeutic approach for MM, the objective of this study is to investigate the potential of CAPE for in vivo applications by using magnetic resonance imaging (MRI)-capable superparamagnetic iron oxide nanoparticles (IONP) as carriers. Cyclo (Arg-Gly-Asp-D-Phe-Cys) (RGD) is conjugated to IONP (RGD-IONP/CAPE) to target the overexpressed αvß3 integrin on MM cells for receptor-mediated internalization and intracellular delivery of CAPE. A stable loading of CAPE on IONP can be achieved with a loading efficiency of 48.7% ± 3.3% (wt%). The drug-release studies indicate RGD-IONP/CAPE is stable at physiological (pH 7.4) and basic pH (pH 9.5) and subject to release of CAPE at acidic pH (pH 5.5) mimicking the tumor and lysosomal condition. RGD-IONP/CAPE causes cytotoxicity specific to human MM RPMI8226, U266, and NCI-H929 cells, but not to normal peripheral blood mononuclear cells (PBMCs), with IC50s of 7.97 ± 1.39, 16.75 ± 1.62, and 24.38 ± 1.71 µM after 72-h treatment, respectively. Apoptosis assays indicate RGD-IONP/CAPE induces apoptosis of RPMI8226 cells through a caspase-9 mediated intrinsic pathway, the same as applying CAPE alone. The apoptogenic effect of RGD-IONP/CAPE was also confirmed on the RPMI8226 cells co-cultured with human bone marrow stromal cells HS-5 in a Transwell model to mimic the MM microenvironment in the bone marrow. In conclusion, we demonstrate that water-insoluble CAPE can be loaded to RGD-IONP to greatly improve the biocompatibility and significantly inhibit the growth of MM cells in vitro through the induction of apoptosis. This study paves the way for investigating the MRI-trackable delivery of CAPE for MM treatment in animal models in the future.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38837187

RESUMO

BACKGROUND: The mean wait time for new patient appointments has been growing across specialties, including obstetrics and gynecology, in recent years. This study aimed to assess the impact of insurance type (Medicaid versus commercial insurance) on new patient appointment wait times in general obstetrics and gynecology practices. METHODS: A cross-sectional study used covert mystery calls to general obstetrician gynecologists. Physicians were selected from the American College of Obstetricians and Gynecologists directory and stratified by districts to ensure nationwide representation. Wait times for new patient appointments were collected and analyzed. RESULTS: Regardless of insurance type, the mean wait time for all obstetrician gynecologists was 29.9 business days. Medicaid patients experienced a marginally longer wait time of 4.8% (Ratio: 1.048). While no statistically significant difference in wait times based on insurance type was observed (P=0.39), the data revealed other impactful factors. Younger physicians and those in university-based practices had longer wait times. The gender of the physician also influenced wait times, with female physicians having a mean wait time of 34.7 days compared to 22.7 days for male physicians (P=0.03). Additionally, geographical variations were noted, with physicians in American College of Obstetricians and Gynecologists District I (Atlantic Provinces, CT, ME, MA, NH, RI, VT) having the longest mean wait times and those in District III (DE, NJ, PA) the shortest. CONCLUSIONS: While the type of insurance did not significantly influence the wait times for general obstetrics and gynecology appointments, physician demographic and geographic factors did.

5.
J Clin Transl Sci ; 6(1): e88, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35989858

RESUMO

Introduction: We created a COVID-19 Research Patient and Community Advisory Board (PCAB) to provide patient and community input into clinical and translational research studies. The purpose of this article is to describe the PCAB creation, implementation, and evaluation. Methods: We identified PCAB members who had participated in previous stakeholder engaged activities at our institution and invited their participation. We created a systematic consultation process where researchers could submit plain language research summaries and questions for the PCAB. A facilitated 1-hour virtual consultation was then held where PCAB members provided feedback. We assessed satisfaction of PCAB members and researchers who received consultations using surveys. We also reviewed video recordings of PCAB consultations and reflections from team meetings to identify key lessons learned. Results: Twenty-seven PCAB members took part in 23 consultation sessions. Twenty-two completed an evaluation survey (81% response rate). Most members agreed or strongly agreed their opinions were valued (86%), it was a productive use of time (86%) and were satisfied (86%). Nineteen researchers completed an evaluation survey (83% response rate). Researchers reported positive experiences of working with the PCAB. Additional insights include limited funding in COVID-19 research for equitable community engagement, deficiencies in researcher communication skills, and a lack of cultural humility incorporated into study activities. Conclusions: PCAB members provided recommendations that maximized the patient-centeredness and health equity focus of COVID-19 research. The detailed description of the process of developing, implementing, and evaluating our PCAB can be used as a template for others wishing to replicate this engagement model.

6.
Clin Cancer Res ; 15(1): 39-47, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19118031

RESUMO

PURPOSE: Progression to the castration-resistant state is the incurable and lethal end stage of prostate cancer, and there is strong evidence that androgen receptor (AR) still plays a central role in this process. We hypothesize that knocking down AR will have a major effect on inhibiting growth of castration-resistant tumors. EXPERIMENTAL DESIGN: Castration-resistant C4-2 human prostate cancer cells stably expressing a tetracycline-inducible AR-targeted short hairpin RNA (shRNA) were generated to directly test the effects of AR knockdown in C4-2 human prostate cancer cells and tumors. RESULTS: In vitro expression of AR shRNA resulted in decreased levels of AR mRNA and protein, decreased expression of prostate-specific antigen (PSA), reduced activation of the PSA-luciferase reporter, and growth inhibition of C4-2 cells. Gene microarray analyses revealed that AR knockdown under hormone-deprived conditions resulted in activation of genes involved in apoptosis, cell cycle regulation, protein synthesis, and tumorigenesis. To ensure that tumors were truly castration-resistant in vivo, inducible AR shRNA expressing C4-2 tumors were grown in castrated mice to an average volume of 450 mm(3). In all of the animals, serum PSA decreased, and in 50% of them, there was complete tumor regression and disappearance of serum PSA. CONCLUSIONS: Whereas castration is ineffective in castration-resistant prostate tumors, knockdown of AR can decrease serum PSA, inhibit tumor growth, and frequently cause tumor regression. This study is the first direct evidence that knockdown of AR is a viable therapeutic strategy for treatment of prostate tumors that have already progressed to the castration-resistant state.


Assuntos
Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos , Animais , Castração , Linhagem Celular Tumoral , Marcação de Genes , Humanos , Masculino , Camundongos , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/patologia , Transplante Heterólogo
7.
West J Nurs Res ; 38(11): 1433-1447, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27330047

RESUMO

The purpose of the study is to assess the relationship between the prevalence of metabolic syndrome-related risk factors and work tenure among office workers. A 10-year cohort analysis was conducted using employees' health examinations given to new employees within 1 or 2 years of joining the firm and every 5 years thereafter. Age-adjusted odds ratios (95% confidence interval [CI], p < .05) were calculated based on a contrast test with general estimating equations. Specifically, the age-adjusted odds ratios and CIs of those with 20 ± 1 years of work, compared with those with 1 to 2 years of work, were as follows: triglycerides (≥150 mg/dl) 3.01 (2.11, 4.28), waist circumference (male ≥90 cm) 2.70 (1.63, 4.45), and fasting glucose (≥100 mg/dl) 2.67 (1.78, 4.01). The findings of the relationship between metabolic syndrome risk and work tenure as well as the baseline health data of new employees provide a foundation for developing a workplace health management system.

8.
J Investig Med ; 50(2): 110-5, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11930948

RESUMO

BACKGROUND: The presence of Type 2 diabetes mellitus (DM) is one of the strongest predictors of cardiovascular disease (CVD) in women. Although the specific mechanisms underlying this increased risk are unknown, one factor that may contribute to CVD in women with Type 2 DM is impaired fibrinolysis. Healthy premenopausal women have a low rate of CVD and excellent fibrinolytic potential. Impairment in fibrinolysis in people with DM has been demonstrated mainly in men, whereas the fibrinolytic potential of women with Type 2 DM has not been characterized well. This pilot study compared fibrinolytic measures in premenopausal women and men with DM with those of healthy age-matched control women and men to help determine whether fibrinolysis is abnormal in women with DM. METHODS: Fibrinolytic measurements included euglobulin clot lysis time (ELT), fibrinogen, plasminogen activator inhibitor 1, and tissue-type plasminogen activator. RESULTS: Poststasis ELT was significantly impaired in the women with DM as compared with the control women. The men with DM had a tendency toward slower poststasis ELT than did the control men, but the differences between the men's groups were not significant. In the women's groups only, we observed a trend toward increased plasminogen activator inhibitor 1 among the women with DM. CONCLUSIONS: Women with DM have a more significant abnormality in poststasis ELT than do men with DM as compared with sex-specific counterparts without DM.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Fibrinólise , Adulto , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Feminino , Fibrinogênio/metabolismo , Humanos , Masculino , Projetos Piloto , Inibidor 1 de Ativador de Plasminogênio/sangue , Pré-Menopausa , Soroglobulinas/metabolismo , Caracteres Sexuais , Ativador de Plasminogênio Tecidual/sangue
9.
J Biomol Screen ; 16(7): 694-705, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21602485

RESUMO

The type II secretion (T2S) system in gram-negative bacteria comprises the Sec and Tat pathways for translocating proteins into the periplasm and an outer membrane secretin for transporting proteins into the extracellular space. To discover Sec/Tat/T2S pathway inhibitors as potential new therapeutics, the authors used a Pseudomonas aeruginosa bioluminescent reporter strain responsive to SecA depletion and inhibition to screen compound libraries and characterize the hits. The reporter strain placed a luxCDABE operon under regulation of a SecA depletion-responsive upregulated promoter in a secA deletion background complemented with an ectopic lac-regulated secA copy. Bioluminescence was indirectly proportional to the isopropyl-ß-D-thiogalactopyranoside concentration and stimulated by azide, a known SecA ATPase inhibitor. A total of 96 compounds (0.1% of 73,000) were detected as primary hits due to stimulation of luminescence with a z score ≥5. Direct secretion assays of the nine most potent hits, representing five chemical scaffolds, revealed that they do not inhibit SecA-mediated secretion of ß-lactamase into the periplasm but do inhibit T2S-mediated extracellular secretion of elastase with IC(50) values from 5 to 25 µM. In addition, seven of the nine compounds also inhibited the T2S-mediated extracellular secretion of phospholipase C by P. aeruginosa and protease activity by Burkholderia pseudomallei.


Assuntos
Burkholderia pseudomallei/efeitos dos fármacos , Genes Reporter/genética , Ensaios de Triagem em Larga Escala , Proteínas Luminescentes/análise , Pseudomonas aeruginosa/efeitos dos fármacos , Adenosina Trifosfatases/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Burkholderia pseudomallei/genética , Inibidores Enzimáticos/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas Luminescentes/genética , Proteínas de Membrana Transportadoras/genética , Pseudomonas aeruginosa/genética , Canais de Translocação SEC , Proteínas SecA , Via Secretória/efeitos dos fármacos , Via Secretória/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Azida Sódica/farmacologia
10.
J Med Microbiol ; 59(Pt 12): 1403-1414, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20724509

RESUMO

Burkholderia pseudomallei has been shown to produce more than one capsular polysaccharide (CPS). Analysis of the B. pseudomallei genome has revealed that the organism contains four CPS operons (I-IV). One of these operons (CPS III) was selected for further study. Comparative sequencing analysis revealed that the genes encoding CPS III are present in B. pseudomallei and Burkholderia thailandensis but not in Burkholderia mallei. In this study, CPS III was not found to contribute to the virulence of B. pseudomallei. Strains containing mutations in CPS III had the same LD(50) value as the wild-type when tested in an animal infection model. Production of CPS III was shown to be induced in water but inhibited in 30% normal human serum using a lux reporter fusion assay. Microarray analysis of capsule gene expression in infected hamsters revealed that the genes encoding CPS III were not significantly expressed in vivo compared with the genes encoding the previously characterized mannoheptose capsule (CPS I), which is an important virulence factor in B. pseudomallei. Glycosyl-composition analysis by combined GC/MS indicated that the CPS III genes are involved in the synthesis of a capsule composed of galactose, glucose, mannose and xylose.


Assuntos
Cápsulas Bacterianas/metabolismo , Burkholderia pseudomallei/metabolismo , Animais , Cápsulas Bacterianas/genética , Burkholderia pseudomallei/patogenicidade , Cricetinae , Feminino , Regulação Bacteriana da Expressão Gênica/fisiologia , Melioidose/microbiologia , Mesocricetus , Análise em Microsséries , Mutação , Virulência
11.
J Immunol ; 173(3): 2031-40, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15265938

RESUMO

Some bacterial products possess multiple immunomodulatory effects and thereby complex mechanisms of action. Exogenous administration of an important Pseudomonas aeruginosa virulence factor, exoenzyme S (ExoS) induces potent monocyte activation leading to the production of numerous proinflammatory cytokines and chemokines. However, ExoS is also injected directly into target cells, inducing cell death through its multiple effects on signaling pathways. This study addresses the mechanisms used by ExoS to induce monocyte activation. Exogenous administration resulted in specific internalization of ExoS via an actin-dependent mechanism. However, ExoS-mediated cellular activation was not inhibited if internalization was blocked, suggesting an alternate mechanism of activation. ExoS bound a saturable and specific receptor on the surface of monocytic cells. ExoS, LPS, and peptidoglycan were all able to induce tolerance and cross-tolerance to each other suggesting the involvement of a TLR in ExoS-recognition. ExoS activated monocytic cells via a myeloid differentiation Ag-88 pathway, using both TLR2 and the TLR4/MD-2/CD14 complex for cellular activation. Interestingly, the TLR2 activity was localized to the C-terminal domain of ExoS while the TLR4 activity was localized to the N-terminal domain. This study provides the first example of how different domains of the same molecule activate two TLRs, and also highlights the possible overlapping pathophysiological processes possessed by microbial toxins.


Assuntos
ADP Ribose Transferases/química , Toxinas Bacterianas/química , Glicoproteínas de Membrana/agonistas , Monócitos/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia , Receptores de Superfície Celular/agonistas , ADP Ribose Transferases/fisiologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Antígenos de Diferenciação/fisiologia , Antígenos de Superfície/fisiologia , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/metabolismo , Citocalasina D/farmacologia , Corantes Fluorescentes , Humanos , Receptores de Lipopolissacarídeos/fisiologia , Lipopolissacarídeos/farmacologia , Antígeno 96 de Linfócito , Substâncias Macromoleculares , Monócitos/metabolismo , Fator 88 de Diferenciação Mieloide , Peptidoglicano/farmacologia , Estrutura Terciária de Proteína , Receptores Imunológicos/antagonistas & inibidores , Receptores Imunológicos/fisiologia , Proteínas Recombinantes de Fusão/farmacologia , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Receptores Toll-Like , Fator de Necrose Tumoral alfa/biossíntese
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA