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1.
Cureus ; 16(2): e54475, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38510870

RESUMEN

Background It is generally accepted that breastfeeding is a practice that provides valuable health benefits to both mother and baby. However, the COVID-19 pandemic unveiled questions regarding the safety of breastfeeding, leading to potential hesitation among the public. Our study seeks to appreciate the public's understanding and attitudes toward breastfeeding during the COVID-19 pandemic. Methods An anonymous survey was distributed online through social media platforms. Demographic information was collected with questions specifically analyzing the knowledge and attitude of each participant. Calculations were performed using Spearman's rho correlations to determine significant differences. Results Thirty-nine women were recruited. The average overall knowledge score was 93% correct. 87% of participants believe breastfeeding is better than formula feeding, and 92% stated they would breastfeed their infant if they knew it could protect their child from COVID-19. Discussion The results of our study indicated that although overall knowledge of breastfeeding during the COVID-19 pandemic was well understood, higher levels of education may play a role in the depth of one's knowledge. In addition, while participants were reporting high levels of education about breastfeeding from their healthcare providers, few were receiving data specific to the pandemic. The data gathered from this study may help to target future educational initiatives.

2.
Front Mol Biosci ; 10: 1104505, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37228586

RESUMEN

Despite substantial improvements in the treatment landscape of prostate cancer, the evolution of hormone therapy-resistant and metastatic prostate cancer remains a major cause of cancer-related death globally. The mainstay of treatment for advanced prostate cancer is targeting of androgen receptor signaling, including androgen deprivation therapy plus second-generation androgen receptor blockade (e.g., enzalutamide, apalutamide, darolutamide), and/or androgen synthesis inhibition (abiraterone). While these agents have significantly prolonged the lives of patients with advanced prostate cancer, is nearly universal. This therapy resistance is mediated by diverse mechanisms, including both androgen receptor-dependent mechanisms, such as androgen receptor mutations, amplifications, alternative splicing, and amplification, as well as non-androgen receptor-mediated mechanisms, such as lineage plasticity toward neuroendocrine-like or epithelial-mesenchymal transition (EMT)-like lineages. Our prior work identified the EMT transcriptional regulator Snail as critical to hormonal therapy resistance and is commonly detected in human metastatic prostate cancer. In the current study, we sought to interrogate the actionable landscape of EMT-mediated hormone therapy resistant prostate cancer to identify synthetic lethality and collateral sensitivity approaches to treating this aggressive, therapy-resistant disease state. Using a combination of high-throughput drug screens and multi-parameter phenotyping by confluence imaging, ATP production, and phenotypic plasticity reporters of EMT, we identified candidate synthetic lethalities to Snail-mediated EMT in prostate cancer. These analyses identified multiple actionable targets, such as XPO1, PI3K/mTOR, aurora kinases, c-MET, polo-like kinases, and JAK/STAT as synthetic lethalities in Snail+ prostate cancer. We validated these targets in a subsequent validation screen in an LNCaP-derived model of resistance to sequential androgen deprivation and enzalutamide. This follow-up screen provided validation of inhibitors of JAK/STAT and PI3K/mTOR as therapeutic vulnerabilities for both Snail+ and enzalutamide-resistant prostate cancer.

3.
Med Sci Educ ; 32(2): 275-277, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35528302

RESUMEN

Medical education needs real-time documentation of professionalism for feedback and improvement. "ClassDojo™" is a behavioral tracking mobile app used in elementary education in USA with limited presence in medical education. A protocol adapting ClassDojo™ in pre-clerkship curriculum was developed and implemented. ClassDojo™ serves as an effective means of formative assessment of medical students' professionalism.

4.
Mol Cancer Ther ; 19(12): 2516-2527, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33158998

RESUMEN

Colorectal cancer is the third most common cancer in the United States and responsible for over 50,000 deaths each year. Therapeutic options for advanced colorectal cancer are limited, and there remains an unmet clinical need to identify new treatments for this deadly disease. To address this need, we developed a precision medicine pipeline that integrates high-throughput chemical screens with matched patient-derived cell lines and patient-derived xenografts (PDX) to identify new treatments for colorectal cancer. High-throughput screens of 2,100 compounds were performed across six low-passage, patient-derived colorectal cancer cell lines. These screens identified the CDK inhibitor drug class among the most effective cytotoxic compounds across six colorectal cancer lines. Among this class, combined targeting of CDK1, 2, and 9 was the most effective, with IC50s ranging from 110 nmol/L to 1.2 µmol/L. Knockdown of CDK9 in the presence of a CDK2 inhibitor (CVT-313) showed that CDK9 knockdown acted synergistically with CDK2 inhibition. Mechanistically, dual CDK2/9 inhibition induced significant G2-M arrest and anaphase catastrophe. Combined CDK2/9 inhibition in vivo synergistically reduced PDX tumor growth. Our precision medicine pipeline provides a robust screening and validation platform to identify promising new cancer therapies. Application of this platform to colorectal cancer pinpointed CDK2/9 dual inhibition as a novel combinatorial therapy to treat colorectal cancer.


Asunto(s)
Antineoplásicos/farmacología , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Medicina de Precisión , Inhibidores de Proteínas Quinasas/farmacología , Animales , Biomarcadores de Tumor , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/metabolismo , Quinasa 2 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 9 Dependiente de la Ciclina/antagonistas & inhibidores , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas/métodos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Sinergismo Farmacológico , Femenino , Ensayos Analíticos de Alto Rendimiento , Humanos , Masculino , Ratones , Mutación , Medicina de Precisión/métodos , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Differentiation ; 90(4-5): 77-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26558987

RESUMEN

Regeneration of ß-cells in diabetic patients is an important goal of diabetes research. Islet Neogenesis Associated Protein (INGAP) was discovered in the partially duct-obstructed hamster pancreas. Its bioactive fragment, pentadecapeptide 104-118 (INGAP-P), has been shown to reverse diabetes in animal models and to improve glucose homeostasis in patients with diabetes in clinical trials. Further development of INGAP as a therapy for diabetes requires identification of target cells in the pancreas and characterization of the mechanisms of action. We hypothesized that adult human pancreatic ductal cells retain morphogenetic plasticity and can be induced by INGAP to undergo endocrine differentiation. To test this hypothesis, we treated the normal human pancreatic ductal cell line (HPDE) with either INGAP-P or full-length recombinant protein (rINGAP) for short-term periods. Our data show that this single drug treatment induces both proliferation and transdifferentiation of HPDE cells, the latter being characterized by the rapid sequential activation of endocrine developmental transcription factors Pdx-1, Ngn3, NeuroD, IA-1, and MafA and subsequently the expression of insulin at both the mRNA and the protein levels. After 7 days, C-peptide was detected in the supernatant of INGAP-treated cells, reflecting their ability to secrete insulin. The magnitude of differentiation was enhanced by embedding the cells in Matrigel, which led to islet-like cluster formation. The islet-like clusters cells stained positive for nuclear Pdx-1 and Glut 2 proteins, and were expressing Insulin mRNA. These new data suggest that human adult pancreatic ductal cells retain morphogenetic plasticity and demonstrate that a short exposure to INGAP triggers their differentiation into insulin-expressing cells in vitro. In the context of the urgent search for a regenerative and/or cellular therapy for diabetes, these results make INGAP a promising therapeutic candidate.


Asunto(s)
Antígenos de Neoplasias/farmacología , Biomarcadores de Tumor/farmacología , Péptido C/metabolismo , Proliferación Celular/efectos de los fármacos , Transdiferenciación Celular/efectos de los fármacos , Citocinas/farmacología , Diabetes Mellitus/terapia , Insulina/metabolismo , Fragmentos de Péptidos/farmacología , Factores de Transcripción/fisiología , Adulto , Animales , Antígenos de Neoplasias/genética , Biomarcadores de Tumor/genética , Línea Celular , Colágeno/farmacología , Cricetinae , Combinación de Medicamentos , Humanos , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Laminina/farmacología , Lectinas Tipo C/genética , Conductos Pancreáticos , Proteínas Asociadas a Pancreatitis , Proteoglicanos/farmacología , Proteínas Recombinantes/farmacología
7.
Am J Physiol Endocrinol Metab ; 303(7): E917-27, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-22850686

RESUMEN

Islet neogenesis-associated protein (INGAP) was discovered in the partially duct-obstructed hamster pancreas as a factor inducing formation of new duct-associated islets. A bioactive portion of INGAP, INGAP(104-118) peptide (INGAP-P), has been shown to have neogenic and insulin-potentiating activity in numerous studies, including recent phase 2 clinical trials that demonstrated improved glucose homeostasis in both type 1 and type 2 diabetic patients. Aiming to improve INGAP-P efficacy and to understand its mechanism of action, we cloned the full-length protein (rINGAP) and compared the signaling events induced by the protein and the peptide in RIN-m5F cells that respond to INGAP with an increase in proliferation. Here, we show that, although both rINGAP and INGAP-P signal via the Ras/Raf/ERK pathway, rINGAP is at least 100 times more efficient on a molar basis than INGAP-P. For either ligand, ERK1/2 activation appears to be pertussis toxin sensitive, suggesting involvement of a G protein-coupled receptor(s). However, there are clear differences between the peptide and the protein in interactions with the cell surface and in the downstream signaling. We demonstrate that fluorescent-labeled rINGAP is characterized by clustering on the membrane and by slow internalization (≤5 h), whereas INGAP-P does not cluster and is internalized within minutes. Signaling by rINGAP appears to involve Src, in contrast to INGAP-P, which appears to activate Akt in addition to the Ras/Raf/ERK1/2 pathway. Thus our data suggest that interactions of INGAP with the cell surface are important to consider for further development of INGAP as a pharmacotherapy for diabetes.


Asunto(s)
Antígenos de Neoplasias/farmacología , Biomarcadores de Tumor/farmacología , Citocinas/farmacología , Islotes Pancreáticos/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Proteínas Recombinantes/farmacología , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Clonación Molecular , Lectinas Tipo C , Proteínas Asociadas a Pancreatitis , Toxina del Pertussis/farmacología , Ratas , Transducción de Señal/efectos de los fármacos
8.
J Endocrinol ; 211(3): 231-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21933872

RESUMEN

Given the inherent therapeutic potential of the morphogenetic plasticity of adult human islets, the identification of factors controlling their cellular differentiation is of interest. The epidermal growth factor (EGF) family has been identified previously in the context of pancreatic organogenesis. We examined the role of EGF in an in vitro model whereby adult human islets are embedded in a collagen gel and dedifferentiated into duct-like epithelial structures (DLS). We demonstrated that DLS formation was EGF dependent, while residual DLS formation in the absence of added EGF was abrogated by EGF receptor inhibitor treatment. With respect to signaling, EGF administration led to an increase in c-Jun NH2-terminal kinase (JNK) phosphorylation early in DLS formation and in AKT and extracellular signal-regulated kinase (ERK) phosphorylation late in the process of DLS formation, concomitant with the increased proliferation of dedifferentiated cells. In the absence of EGF, these phosphorylation changes are not seen and the typical increase in DLS epithelial cell proliferation seen after 10 days in culture is attenuated. Thus, in our model, EGF is necessary for islet cell dedifferentiation, playing an important role in both the onset of DLS formation (through JNK) and in the proliferation of these dedifferentiated cells (through AKT and ERK).


Asunto(s)
Desdiferenciación Celular/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , Adulto , Secuencia de Bases , Desdiferenciación Celular/genética , Desdiferenciación Celular/fisiología , Cartilla de ADN/genética , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Femenino , Expresión Génica , Humanos , Técnicas In Vitro , Islotes Pancreáticos/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Ligandos , Masculino , Persona de Mediana Edad , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos
9.
Endocrinology ; 151(4): 1462-72, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20176718

RESUMEN

Studies of long-standing type 2 diabetes (T2D) report a deficit in beta-cell mass due to increased apoptosis, whereas neogenesis and replication are unaffected. It is unclear whether these changes are a cause or a consequence of T2D. Moreover, whereas islet morphogenetic plasticity has been demonstrated in vitro, the in situ plasticity of islets, as well as the effect of T2D on endocrine differentiation, is unknown. We compared beta-cell volume, neogenesis, replication, and apoptosis in pancreata from lean and obese (body mass index > or = 27 kg/m(2)) diabetic (5 +/- 2 yr since diagnosis) and nondiabetic cadaveric donors. We also subjected isolated islets from diabetic (3 +/- 1 yr since diagnosis) and nondiabetic donors to an established in vitro model of islet plasticity. Differences in beta-cell volume between diabetic and nondiabetic donors were consistently less pronounced than those reported in long-standing T2D. A compensatory increase in beta-cell neogenesis appeared to mediate this effect. Studies of induced plasticity indicated that islets from diabetic donors were capable of epithelial dedifferentiation but did not demonstrate regenerative potential, as was seen in islets from nondiabetic donors. This deficiency was associated with the overexpression of Notch signaling molecules and a decreased neurogenin-3(+) cell frequency. One interpretation of these results would be that decreased beta-cell volume is a consequence, not a cause, of T2D, mediated by increased apoptosis and attenuated beta-cell (re)generation. However, other explanations are also possible. It remains to be seen whether the morphogenetic plasticity of human islets, deficient in vitro in islets from diabetic donors, is a component of normal beta-cell mass dynamics.


Asunto(s)
Forma de la Célula , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/patología , Páncreas/patología , Análisis de Varianza , Apoptosis , Recuento de Células , Proliferación Celular , Tamaño de la Célula , Células Cultivadas , Diabetes Mellitus Tipo 2/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Insulina/análisis , Células Secretoras de Insulina/química , Células Secretoras de Insulina/metabolismo , Masculino , Persona de Mediana Edad , Páncreas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
10.
Protein Expr Purif ; 69(1): 1-8, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19635567

RESUMEN

Islet Neogenesis Associated Protein (INGAP) is implicated in pancreatic islet neogenesis. INGAP peptide, a pentadecapeptide comprising amino acids 104-118, reverses diabetes in rodents and improves glucose homeostasis in patients with diabetes. The mechanism of INGAP action is unknown, but such studies would benefit from the availability of the full-length recombinant protein (rINGAP). Here we report the production of rINGAP from 293-SF cells following lentiviral transduction, and its characterization by MALDI-TOF and Q-TOF Mass Spectrometry, and HPLC. Importantly, we show that rINGAP exhibits 100x the bioactivity of INGAP peptide on a molar basis in an in vitro assay of human islet regeneration.


Asunto(s)
Antígenos de Neoplasias/biosíntesis , Biomarcadores de Tumor/biosíntesis , Lectinas Tipo C/biosíntesis , Proteínas Recombinantes/biosíntesis , Secuencia de Aminoácidos , Animales , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/aislamiento & purificación , Biomarcadores de Tumor/química , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/aislamiento & purificación , Células Cultivadas , Cromatografía Líquida de Alta Presión , Cricetinae , Regulación de la Expresión Génica , Humanos , Islotes Pancreáticos/fisiología , Lectinas Tipo C/química , Lectinas Tipo C/genética , Lectinas Tipo C/aislamiento & purificación , Lentivirus/genética , Espectrometría de Masas , Mesocricetus , Datos de Secuencia Molecular , Peso Molecular , Proteínas Asociadas a Pancreatitis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Regeneración/fisiología , Fracciones Subcelulares/metabolismo , Transducción Genética
11.
Biochem J ; 362(Pt 2): 367-73, 2002 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11853544

RESUMEN

Chondrocyte dedifferentiation has been noted in osteoarthritic cartilage, but the contribution of this phenomenon is poorly understood. Interleukin (IL)-1beta, the major pro-inflammatory cytokine found in osteoarthritic synovial fluid, induces the dedifferentiation of cultured articular chondrocytes, whereas E-series prostaglandins (PGE) are capable of inducing cell differentiation. Since PGE(2) synthesis is up-regulated by IL-1beta, we addressed the question of whether the state of chondrocyte differentiation may influence the production of IL-1-induced PGE(2) by modulating cyclooxygenase (COX)-2 expression. Immortalized human articular chondrocytes, (tsT/AC62) cultured in monolayer after passage through alginate matrix (alg+) produced 5-fold greater amounts of PGE(2) than continuous monolayer cultures (alg-) after stimulation with IL-1beta. Moreover, IL-1beta induced COX-2 expression at 0.01 ng/ml in (alg+) cells, whereas a 100-fold higher dose of cytokine was necessary for stimulation in (alg-) cells. SB203580, a selective p38 mitogen-activated protein kinase (MAPK) inhibitor, completely abolished the IL-1beta-induced COX-2 mRNA. Overexpression of p38 MAPK induces a COX-2 reporter, whereas overexpression of dominant negative p38 MAPK represses IL-1beta-induced promoter expression. Interestingly, IL-1beta-induced p38 MAPK activity was greatly enhanced in (alg+) compared with (alg-) cells. Our results suggest that differentiated articular chondrocytes are highly responsive to IL-1beta and that p38 MAPK mediates this response by inducing COX-2 gene expression.


Asunto(s)
Cartílago Articular/enzimología , Condrocitos/enzimología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Interleucina-1/farmacología , Isoenzimas/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Prostaglandina-Endoperóxido Sintasas/genética , Alginatos , Técnicas de Cultivo de Célula/métodos , Línea Celular , Ciclooxigenasa 2 , Dinoprostona/metabolismo , Genes Reporteros , Ácido Glucurónico , Ácidos Hexurónicos , Humanos , Proteína Accesoria del Receptor de Interleucina-1 , Isoenzimas/biosíntesis , Proteínas de la Membrana , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Proteínas/genética , ARN Mensajero/genética , Receptores de Interleucina-1/genética , Proteínas Recombinantes/biosíntesis , Transcripción Genética/genética , Transfección , Proteínas Quinasas p38 Activadas por Mitógenos
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