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1.
World J Urol ; 42(1): 337, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38762841

RESUMEN

INTRODUCTION: To assess the impact of kidney function in patients with BPH undergoing surgery prior to Transurethral resection of prostate (TURP), Laser enucleation of the prostate (LEP), and Laser Vaporization of the prostate (LVP) on operative and post-operative outcomes using the ACS-NSQIP database. METHODS: The ACS-NSQIP database was reviewed for patients that underwent TURP, LEP and LVP for treatment of patients with BPH between the years of 2008 and 2021. Demographics, comorbidities, bleeding disorders, operative time, and surgical procedure performed were collected for comparison between Kidney function groups: G1, normal/high function; G2-G3, mild/moderate kidney disease; and G4-G5, severe kidney disease. The 30-day peri-operative complications were measured and a multivariate logistic regression analysis was performed while adjusting for all confounding variables. Propensity score matching was performed between the G1 and G4-G5 cohorts. RESULTS: A total of 83,020 patients were included. On multivariable regression, in the G2-G3 cohort, patients were at significantly increased risk for renal complications with OR = 2.43[1.56-3.79]. After propensity score matching, the G4-G5 cohort showed increased odds of pneumonia OR = 4.02[1.343-12.056], renal complications with OR = 7.62[2.283-25.411], cardiac complications OR = 4.53[1.531-13.411], and sepsis/septic shock OR = 1.76[1.091-2.834]. They also had a higher need for blood transfusion OR = 3.58[2.242-5.714], and prolonged hospital stay with OR = 1.49[1.296-1.723]. CONCLUSION: Pre-operative kidney disease may pose an increased risk of complications for patients undergoing endoscopic BPH surgery. The literature lacks information on the effect of pre-operative kidney disease on endoscopic BPH surgeries. Further studies are required to compare post-operative outcomes of LEP and LVP as compared to TURP across kidney function status.


Asunto(s)
Bases de Datos Factuales , Enfermedades Renales , Complicaciones Posoperatorias , Puntaje de Propensión , Hiperplasia Prostática , Humanos , Masculino , Anciano , Complicaciones Posoperatorias/epidemiología , Hiperplasia Prostática/cirugía , Hiperplasia Prostática/complicaciones , Persona de Mediana Edad , Enfermedades Renales/epidemiología , Enfermedades Renales/cirugía , Resultado del Tratamiento , Endoscopía/métodos , Estudios Retrospectivos , Prostatectomía/métodos , Resección Transuretral de la Próstata
2.
Headache ; 64(2): 156-171, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38235605

RESUMEN

OBJECTIVE: To describe the impact of migraine on functioning based on comprehensive data collection, analysis, and reporting of patients' experiences. BACKGROUND: Qualitative research conducted to understand patients' perspectives on living with migraine has often focused on narrow topics or specific groups of patients or has been selectively reported. METHODS: Qualitative interviews with 71 participants were conducted during two concept elicitation studies as part of the Migraine Clinical Outcome Assessment System (MiCOAS) project, an FDA grant-funded program designed to develop a core set of patient-centered outcome measures for migraine clinical trials. Participants self-reported being diagnosed with migraine by a healthcare professional and participated in semi-structured qualitative interviews about their experiences with the symptoms and impacts of migraine. Interview transcripts were coded to identify and define concepts, which were then grouped into broad domains based on conceptual similarities. RESULTS: A total of 66 concepts were identified: 12 for physical functioning, 16 for cognitive functioning, 10 for social role functioning, 19 for emotional and psychological functioning, and 9 related to migraine management. Participants described a complex and varied relationship between migraine attack symptoms and impacts on functioning. Impacts from migraine were further influenced by numerous contextual factors, such as people's individual social environments and the level of day-to-day demand for functioning they face. CONCLUSION: Findings showed that migraine impacted individual functioning in multiple ways and the nature of these impacts was dependent on social-contextual factors. The results are being used in the development of core measures designed to improve our understanding of the burden of migraine and the efficacy of migraine therapies. The results also offer new insights and raise new questions about migraine experience that can be used to guide future research.


Asunto(s)
Emociones , Trastornos Migrañosos , Humanos , Investigación Cualitativa , Autoinforme , Cognición , Trastornos Migrañosos/terapia
3.
World J Urol ; 41(1): 257-262, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36416925

RESUMEN

PURPOSE: Benign prostatic hyperplasia (BPH) affects nearly half of men in their fifties. Patients often search the Internet to better understand their diagnosis, but online health information is not well regulated and can be difficult for patients to comprehend. This study aims to evaluate not only readability, but also the quality of online information about BPH, as well as the effect of commercial bias on readability and quality. METHODS: Three search engines (Google, Bing, and DuckDuckGo) were used with broad search terms including "BPH," "BPH treatment," and "BPH surgery," to mimic a patient diagnosed with BPH seeking further information. 204 total websites were identified, of which 62 were unique websites. Among those unique websites, 23 were advertisements. Three readability formulas (Flesch-Kincaid Grade Level, Flesch-Kincaid Reading Ease, SMOG) were used to generate readability scores. DISCERN standardized questionnaire was used to evaluate website quality. RESULTS: Average reading level of online information about BPH was significantly higher than the recommended level by the American Medical Association (AMA) and United States Department of Health and Human Services (USDHHS). Advertisements had significantly easier readability than nonadvertisements. Average website quality was "excellent" for nonadvertisements, but only "fair" for advertisements. CONCLUSION: Although advertisements may hold optimal search result positions and have better readability than nonadvertisements, they have biased and lower quality information. It is important to guide patients to high quality online information of appropriate reading level. Continued efforts should be made to create and share with patients high quality resources with improved readability to facilitate comprehension and minimize misinformation.


Asunto(s)
Información de Salud al Consumidor , Hiperplasia Prostática , Masculino , Estados Unidos , Humanos , Comprensión , Hiperplasia Prostática/terapia , Motor de Búsqueda , Comunicación , Internet
4.
Headache ; 63(7): 953-964, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37140142

RESUMEN

BACKGROUND: There is renewed emphasis on including patients in determining, defining, and prioritizing outcomes for migraine treatment. OBJECTIVES: To obtain insights directly from people living with migraine on their priorities for treatment. METHODS: A total of 40 qualitative interviews were conducted as part of the Migraine Clinical Outcome Assessment System project, a United States Food and Drug Administration grant-funded program to develop a core set of patient-centered outcome measures for migraine clinical trials. Interviews included a structured exercise in which participants rank-ordered pre-defined lists of potential benefits for acute and preventive migraine therapy. The 40 study participants who reported being diagnosed with migraine by a clinician ranked the benefits and explained their rationale. RESULTS: Study participants consistently ranked either pain relief or absence of pain as their top priority for acute treatment. Relief/absence of other migraine symptoms and improved functioning were also prioritized. For preventive treatment, participants prioritized reductions in migraine frequency, symptom severity, and attack duration. Few differences were found between participants with episodic migraine and those with chronic migraine. However, participants with chronic migraine ranked "increased predictability of attacks" much higher than those with episodic migraine. Participants' rankings were influenced by prior expectations and experiences of migraine treatments, which caused many participants to deprioritize desired benefits as unrealistic. Participants also identified several additional priorities, including limited side-effects and reliable treatment efficacy in both acute and preventive treatments. CONCLUSION: The results showed the participants prioritized treatment benefits aligned with existing core clinical outcomes used in migraine research, but also valued benefits that are not typically assessed, such as predictability. Participants also deprioritized important benefits when they believed treatment was unlikely to deliver those outcomes.


Asunto(s)
Trastornos Migrañosos , Humanos , Trastornos Migrañosos/prevención & control , Trastornos Migrañosos/tratamiento farmacológico , Resultado del Tratamiento , Evaluación de Resultado en la Atención de Salud , Manejo del Dolor , Dolor
5.
Headache ; 63(3): 441-454, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36905166

RESUMEN

OBJECTIVES: To capture patients' perspectives on migraine-related cognitive symptoms during pre-headache, headache, post-headache, and interictal periods. BACKGROUND: Migraine-related cognitive symptoms are reported by people with migraine both during and between attacks. Associated with disability, they are increasingly viewed as a priority target for treatment. The Migraine Clinical Outcome Assessment System (MiCOAS) project is focused on developing a patient-centered core set of outcome measures for the evaluation of migraine treatments. The project focuses on incorporating the experience of people living with migraine and the outcomes most meaningful to them. This includes an examination of the presence and functional impact of migraine-related cognitive symptoms and their perceived impact on quality of life and disability. METHODS: Forty individuals with self-reported medically diagnosed migraine were recruited via iterative purposeful sampling for semi-structured qualitative interviews conducted using audio-only web conferencing. Thematic content analysis was performed to identify key concepts around migraine-related cognitive symptoms. Recruitment continued until concept saturation was achieved. RESULTS: Participants described symptoms consistent with migraine-related deficits in language/speech, sustained attention, executive function, and memory that manifest during pre-headache (36/40 [90%] reported ≥1 cognitive feature), headache (35/40 [88%] reported ≥1 cognitive feature), post-headache (27/40 [68%] reported ≥1 cognitive feature), and interictal periods (13/40 [33%] reported ≥1 cognitive feature). Among participants reporting cognitive symptoms during pre-headache, 32/40 (81%) endorsed 2-5 cognitive symptoms. Findings were similar during the headache phase. Participants reported language/speech problems consistent with, for example, impairments in receptive language, expressive language, and articulation. Issues with sustained attention included fogginess, confusion/disorientation, and trouble with concentration/focus. Deficits in executive function included difficulty processing information and reduced capacity for planning and decision-making. Memory issues were reported across all phases of the migraine attack. CONCLUSIONS: This patient-level qualitative study suggests that cognitive symptoms are common for persons with migraine, particularly in the pre-headache and headache phases. These findings highlight the importance of assessing and ameliorating these cognitive problems.


Asunto(s)
Trastornos Migrañosos , Calidad de Vida , Humanos , Calidad de Vida/psicología , Trastornos Migrañosos/diagnóstico , Cefalea , Evaluación de Resultado en la Atención de Salud , Medición de Resultados Informados por el Paciente
6.
Am J Otolaryngol ; 44(4): 103904, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37148847

RESUMEN

OBJECTIVE: Otolaryngology (OTO) is a competitive specialty, and medical school factors outside an applicant's control, such as presence of OTO student resources and an affiliated OTO residency program, can impact the competitiveness of a student's application. This study sought to evaluate the extent of OTO resources United States (U.S.) allopathic medical schools provide to help their students be successful, and to evaluate for medical school factors which may bias toward inequitable distribution of student OTO resources. METHODS: A 48-question cross-sectional survey evaluating the extent of OTO resources was distributed by email to LCME accredited U.S. allopathic medical schools in 2020 and 2021. RESULTS: Schools with residency programs and where faculty were employed through an OTO or surgery department were more likely to have an Otolaryngology Interest Group (OIG), an Otolaryngology Medical Student Education Director (OMSED), and were more likely to provide opportunities for OTO research.


Asunto(s)
Internado y Residencia , Otolaringología , Estudiantes de Medicina , Humanos , Estados Unidos , Facultades de Medicina , Estudios Transversales , Otolaringología/educación
7.
J Biol Chem ; 296: 100445, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33617877

RESUMEN

Within the AGC kinase superfamily, gene fusions resulting from chromosomal rearrangements have been most frequently described for protein kinase C (PKC), with gene fragments encoding either the C-terminal catalytic domain or the N-terminal regulatory moiety fused to other genes. Kinase fusions that eliminate regulatory domains are typically gain of function and often oncogenic. However, several quality control pathways prevent accumulation of aberrant PKC, suggesting that PKC fusions may paradoxically be loss of function. To explore this topic, we used biochemical, cellular, and genome editing approaches to investigate the function of fusions that retain the portion of the gene encoding either the catalytic domain or regulatory domain of PKC. Overexpression studies revealed that PKC catalytic domain fusions were constitutively active but vulnerable to degradation. Genome editing of endogenous genes to generate a cancer-associated PKC fusion resulted in cells with detectable levels of fusion transcript but no detectable protein. Hence, PKC catalytic domain fusions are paradoxically loss of function as a result of their instability, preventing appreciable accumulation of protein in cells. Overexpression of a PKC regulatory domain fusion suppressed both basal and agonist-induced endogenous PKC activity, acting in a dominant-negative manner by competing for diacylglycerol. For both catalytic and regulatory domain fusions, the PKC component of the fusion proteins mediated the effects of the full-length fusions on the parameters examined, suggesting that the partner protein is dispensable in these contexts. Taken together, our findings reveal that PKC gene fusions are distinct from oncogenic fusions and present a mechanism by which loss of PKC function occurs in cancer.


Asunto(s)
Neoplasias/metabolismo , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Animales , Sitios de Unión , Células COS , Dominio Catalítico , Línea Celular Tumoral , Chlorocebus aethiops , Diglicéridos/metabolismo , Transferencia Resonante de Energía de Fluorescencia/métodos , Humanos , Mutación con Pérdida de Función/genética , Fosforilación , Dominios Proteicos , Proteína Quinasa C-alfa/genética , Proteína Quinasa C-alfa/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
8.
Headache ; 62(3): 284-293, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35294046

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is an ongoing global health crisis that has had a range of impacts on people living with migraine. METHODS: Qualitative interviews performed as part of the Migraine Clinical Outcome Assessment System project, a multi-stage Food and Drug Administration-grant funded program to develop a patient-centered core set of outcome measures for use in migraine clinical trials, offered an opportunity to explore the experience of living with migraine during the pandemic as well as to examine whether migraine treatment priorities, symptoms, and associated disability changed due to the pandemic. Semi-structured interviews were conducted in the United States between the summer and fall of 2020 with 40 individuals with self-reported, medically diagnosed migraine who self-reported that they had not tested positive for or been diagnosed with COVID-19. RESULTS: Seventy percent (n = 28) of the sample reported ≥1 pandemic-related impact on their life with migraine. Fourteen participants reported both positive and negative impacts, twelve reported negative impacts only, and two reported positive impacts only. Among those reporting ≥1 pandemic-related impact, nine participants (32%) reported more frequent and five (17%) reported less frequent migraine attacks. Other negative impacts included interrupted medical care (n = 9; 32%), and greater stress (n = 13; 46%). The most frequent positive impact reported was greater access to health care (n = 8; 29%). Ictal and interictal symptoms were not noted to change due to the pandemic, but some respondents reported less disability due to increased flexibility of schedules and reduced expectations. Treatment priorities did not change due to the pandemic. CONCLUSION: The global COVID-19 pandemic has resulted in both negative and positive impacts for people living with migraine. Lessons to be considered when moving into a post-pandemic world include benefits of and satisfaction with telehealth and the benefits and importance of healthy lifestyle habits and flexibility such as improved sleep, reduced stress, and fewer social expectations.


Asunto(s)
COVID-19 , Trastornos Migrañosos , COVID-19/epidemiología , Humanos , Trastornos Migrañosos/diagnóstico , Trastornos Migrañosos/epidemiología , Trastornos Migrañosos/terapia , Pandemias , Investigación Cualitativa , Calidad de Vida , Estados Unidos
9.
Ann Emerg Med ; 79(1): 2-6, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34417071

RESUMEN

STUDY OBJECTIVE: Practice consolidation is common and has been shown to affect the quality and cost of care across multiple health care delivery settings, including hospitals, nursing homes, and physician practices. Despite a long history of large practice management group formation in emergency medicine and intensifying media attention paid to this topic, little is known about the recent practice consolidation trends within the specialty. METHODS: All data were obtained from the Centers for Medicare and Medicaid Services Physician Compare database, which contains physician and group practice data from 2012 to 2020. We assessed practice size changes for both individual emergency physicians and groups. RESULTS: From 2012 to 2020, the proportion of emergency physicians in groups sized less than 25 has decreased substantially from 40.2% to 22.7%. Physicians practicing in groups of more than or equal to 500 physicians increased from 15.5% to 24%. CONCLUSION: Since 2012, we observed a steady trend toward increased consolidation of emergency department practice with nearly 1 in 4 emergency physicians nationally working in groups with more than 500 physicians in 2020 compared with 1 in 7 in 2012. Although the relationship between consolidation is likely to draw the most attention from policymakers or payers seeking to negotiate prices in the near term and advance payment models in the long term, greater attention is required to understand the effects of practice consolidation on emergency care.


Asunto(s)
Medicina de Emergencia/organización & administración , Medicina de Emergencia/tendencias , Práctica de Grupo/organización & administración , Práctica de Grupo/tendencias , Medicina de Emergencia/estadística & datos numéricos , Práctica de Grupo/estadística & datos numéricos , Humanos , Estados Unidos
10.
J Card Surg ; 37(7): 1854-1860, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35434814

RESUMEN

Tricuspid atresia with an absent pulmonary valve is a rare congenital cardiac defect. Although extensive pathological reviews have been published in the past, there are only a handful of cases that have been successfully palliated to the stage of Fontan. We hereby describe the successful management of one such case and review the surgical strategies described in the literature.


Asunto(s)
Procedimiento de Fontan , Atresia Pulmonar , Válvula Pulmonar , Atresia Tricúspide , Humanos , Atresia Pulmonar/diagnóstico por imagen , Atresia Pulmonar/cirugía , Válvula Pulmonar/anomalías , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Atresia Tricúspide/diagnóstico por imagen , Atresia Tricúspide/cirugía
11.
Cardiol Young ; 32(8): 1353-1356, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35199639

RESUMEN

We present the case of a 4-month-old, former 23-week premature baby who underwent patent ductus arteriosus device closure in the cardiac catheterisation lab with an Amplatzer Piccolo™ device at 12 weeks of life. This was complicated by late migration of the device into the aorta resulting in severe obstruction and requiring surgical intervention.


Asunto(s)
Conducto Arterioso Permeable , Dispositivo Oclusor Septal , Aorta , Cateterismo Cardíaco/métodos , Conducto Arterioso Permeable/cirugía , Humanos , Lactante , Recién Nacido de Bajo Peso , Recién Nacido , Dispositivo Oclusor Septal/efectos adversos , Resultado del Tratamiento
12.
J Inherit Metab Dis ; 43(3): 438-458, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31883128

RESUMEN

Urea cycle disorders (UCD) are rare inherited metabolic disorders caused by deficiencies of enzymes and transporters required to convert neurotoxic ammonia into urea. These deficiencies cause elevated blood ammonia, which if untreated may result in death, but even with optimal medical management, often results in recurrent brain damage. There are two major treatments for UCD: medical management or liver transplantation. Both are associated with mortality and morbidity but the evidence comparing outcomes is sparse. Thus, families face a dilemma: should their child be managed medically, or should they undergo a liver transplant? To (a) describe the factors that contribute to treatment choice among parents of children diagnosed with UCD and to (b) organise these factors into a conceptual framework that reflects how these issues interrelate to shape the decision-making experience of this population. Utilising grounded theory, qualitative data were collected through semi-structured interviews with parents (N = 35) and providers (N = 26) of children diagnosed with UCD and parent focus groups (N = 19). Thematic content analysis and selective and axial coding were applied. The framework highlights the life-cycle catalysts that frame families' personal perceptions of risks and benefits and describes the clinical, personal, social, and system factors that drive treatment choice including disease severity, stability, and burden, independence, peer experiences, and cost, coverage and access to quality care. Findings equip providers with evidence upon which to prepare for productive patient interactions about treatment options. They also provide a foundation for the development of patient-centred outcome measures to better evaluate effectiveness of treatments in this population.


Asunto(s)
Conducta de Elección , Toma de Decisiones , Padres/psicología , Trastornos Innatos del Ciclo de la Urea/terapia , Adolescente , Niño , Preescolar , Costo de Enfermedad , Manejo de la Enfermedad , Femenino , Grupos Focales , Humanos , Lactante , Recién Nacido , Entrevistas como Asunto , Trasplante de Hígado/métodos , Masculino , Investigación Cualitativa , Trastornos Innatos del Ciclo de la Urea/cirugía
13.
J Biol Chem ; 293(27): 10744-10756, 2018 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-29773654

RESUMEN

The proto-oncogene Akt/protein kinase B (PKB) is a pivotal signal transducer for growth and survival. Growth factor stimulation leads to Akt phosphorylation at two regulatory sites (Thr-308 and Ser-473), acutely activating Akt signaling. Delineating the exact role of each regulatory site is, however, technically challenging and has remained elusive. Here, we used genetic code expansion to produce site-specifically phosphorylated Akt1 to dissect the contribution of each regulatory site to Akt1 activity. We achieved recombinant production of full-length Akt1 containing site-specific pThr and pSer residues for the first time. Our analysis of Akt1 site-specifically phosphorylated at either or both sites revealed that phosphorylation at both sites increases the apparent catalytic rate 1500-fold relative to unphosphorylated Akt1, an increase attributable primarily to phosphorylation at Thr-308. Live imaging of COS-7 cells confirmed that phosphorylation of Thr-308, but not Ser-473, is required for cellular activation of Akt. We found in vitro and in the cell that pThr-308 function cannot be mimicked with acidic residues, nor could unphosphorylated Thr-308 be mimicked by an Ala mutation. An Akt1 variant with pSer-308 achieved only partial enzymatic and cellular signaling activity, revealing a critical interaction between the γ-methyl group of pThr-308 and Cys-310 in the Akt1 active site. Thus, pThr-308 is necessary and sufficient to stimulate Akt signaling in cells, and the common use of phosphomimetics is not appropriate for studying the biology of Akt signaling. Our data also indicate that pThr-308 should be regarded as the primary diagnostic marker of Akt activity.


Asunto(s)
Código Genético , Imagen Molecular/métodos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina/metabolismo , Treonina/metabolismo , Células Cultivadas , Cristalografía por Rayos X , Humanos , Mutación , Fosforilación , Conformación Proteica , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-akt/química , Proteínas Proto-Oncogénicas c-akt/genética , Serina/química , Serina/genética , Treonina/química , Treonina/genética
14.
Heart Fail Clin ; 15(1): 109-125, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30449374

RESUMEN

Implantable cardioverter-defibrillator and cardiac resynchronization therapy devices have been prescribed for patients with heart failure for several decades. Factors leading to increased usage include significant enhancements in technology and availability of multiple randomized clinical trials demonstrating their benefit with improved implementation of evidence-based guidelines. Despite these advances, gaps still exist in the utilization and referral of these devices, particularly among women. This article reviews the literature on these devices with a focus on gender differences and proposes reasons for why they exist.


Asunto(s)
Dispositivos de Terapia de Resincronización Cardíaca , Desfibriladores Implantables , Insuficiencia Cardíaca/terapia , Utilización de Procedimientos y Técnicas , Derivación y Consulta , Dispositivos de Terapia de Resincronización Cardíaca/clasificación , Dispositivos de Terapia de Resincronización Cardíaca/tendencias , Femenino , Humanos , Masculino , Evaluación de Necesidades , Factores Sexuales
15.
Proc Natl Acad Sci U S A ; 112(9): E937-46, 2015 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25713130

RESUMEN

Environmental cues are transmitted to the interior of the cell via a complex network of signaling hubs. Receptor tyrosine kinases (RTKs) and trimeric G proteins are two such major signaling hubs in eukaryotes. Conventionally, canonical signal transduction via trimeric G proteins is thought to be triggered exclusively by G protein-coupled receptors. Here we used molecular engineering to develop modular fluorescent biosensors that exploit the remarkable specificity of bimolecular recognition, i.e., of both G proteins and RTKs, and reveal the workings of a novel platform for activation of G proteins by RTKs in single living cells. Comprised of the unique modular makeup of guanidine exchange factor Gα-interacting vesicle-associated protein (GIV)/girdin, a guanidine exchange factor that links G proteins to a variety of RTKs, these biosensors provide direct evidence that RTK-GIV-Gαi ternary complexes are formed in living cells and that Gαi is transactivated within minutes after growth factor stimulation at the plasma membrane. Thus, GIV-derived biosensors provide a versatile strategy for visualizing, monitoring, and manipulating the dynamic association of Gαi with RTKs for noncanonical transactivation of G proteins in cells and illuminate a fundamental signaling event regulated by GIV during diverse cellular processes and pathophysiologic states.


Asunto(s)
Técnicas Biosensibles/métodos , Transferencia Resonante de Energía de Fluorescencia/métodos , Proteínas de Unión al GTP , Proteínas Tirosina Quinasas Receptoras , Receptores de Factores de Crecimiento , Transducción de Señal , Animales , Células COS , Chlorocebus aethiops , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Humanos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Factores de Crecimiento/genética , Receptores de Factores de Crecimiento/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
16.
J Biol Chem ; 291(27): 13964-13973, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27226531

RESUMEN

Emerging antibiotic resistance among pathogenic bacteria is an issue of great clinical importance, and new approaches to therapy are urgently needed. Anacardic acid, the primary active component of cashew nut shell extract, is a natural product used in the treatment of a variety of medical conditions, including infectious abscesses. Here, we investigate the effects of this natural product on the function of human neutrophils. We find that anacardic acid stimulates the production of reactive oxygen species and neutrophil extracellular traps, two mechanisms utilized by neutrophils to kill invading bacteria. Molecular modeling and pharmacological inhibitor studies suggest anacardic acid stimulation of neutrophils occurs in a PI3K-dependent manner through activation of surface-expressed G protein-coupled sphingosine-1-phosphate receptors. Neutrophil extracellular traps produced in response to anacardic acid are bactericidal and complement select direct antimicrobial activities of the compound.


Asunto(s)
Ácidos Anacárdicos/farmacología , Anacardium/química , Antibacterianos/farmacología , Trampas Extracelulares/metabolismo , Neutrófilos/efectos de los fármacos , Humanos , Lisofosfolípidos/metabolismo , Estallido Respiratorio , Esfingosina/análogos & derivados , Esfingosina/metabolismo
17.
Proc Natl Acad Sci U S A ; 111(38): E3957-65, 2014 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-25201979

RESUMEN

Growth factor receptor levels are aberrantly high in diverse cancers, driving the proliferation and survival of tumor cells. Understanding the molecular basis for this aberrant elevation has profound clinical implications. Here we show that the pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) suppresses receptor tyrosine kinase (RTK) signaling output by a previously unidentified epigenetic mechanism unrelated to its previously described function as the hydrophobic motif phosphatase for the protein kinase AKT, protein kinase C, and S6 kinase. Specifically, we show that nuclear-localized PHLPP suppresses histone phosphorylation and acetylation, in turn suppressing the transcription of diverse growth factor receptors, including the EGF receptor. These data uncover a much broader role for PHLPP in regulation of growth factor signaling beyond its direct inactivation of AKT: By suppressing RTK levels, PHLPP dampens the downstream signaling output of two major oncogenic pathways, the PI3 kinase/AKT and the Rat sarcoma (RAS)/ERK pathways. Our data are consistent with a model in which PHLPP modifies the histone code to control the transcription of RTKs.


Asunto(s)
Receptores ErbB/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Modelos Biológicos , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Animales , Línea Celular Transformada , Receptores ErbB/genética , Ratones , Ratones Noqueados , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfoproteínas Fosfatasas/genética , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Secuencias Repetitivas de Aminoácido , Transcripción Genética/fisiología
18.
J Biol Chem ; 290(44): 26776-83, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26350460

RESUMEN

Phospholipase C-epsilon (PLCϵ) plays a critical role in G-protein-coupled receptor-mediated inflammation. In addition to its ability to generate the second messengers inositol 1,4,5-trisphosphate and diacylglycerol, PLCϵ, unlike the other phospholipase C family members, is activated in a sustained manner. We hypothesized that the ability of PLCϵ to function as a guanine nucleotide exchange factor (GEF) for Rap1 supports sustained downstream signaling via feedback of Rap1 to the enzyme Ras-associating (RA2) domain. Using gene deletion and adenoviral rescue, we demonstrate that both the GEF (CDC25 homology domain) and RA2 domains of PLCϵ are required for long term protein kinase D (PKD) activation and subsequent induction of inflammatory genes. PLCϵ localization is largely intracellular and its compartmentalization could contribute to its sustained activation. Here we show that localization of PLCϵ to the Golgi is required for activation of PKD in this compartment as well as for subsequent induction of inflammatory genes. These data provide a molecular mechanism by which PLCϵ mediates sustained signaling and by which astrocytes mediate pathophysiological inflammatory responses.


Asunto(s)
Astrocitos/efectos de los fármacos , Fosfoinositido Fosfolipasa C/metabolismo , Trombina/farmacología , Proteínas de Unión al GTP rap1/metabolismo , ras-GRF1/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/citología , Astrocitos/metabolismo , Compartimento Celular , Transferencia Resonante de Energía de Fluorescencia , Regulación de la Expresión Génica , Aparato de Golgi/efectos de los fármacos , Aparato de Golgi/metabolismo , Inflamación , Inositol 1,4,5-Trifosfato/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fosfoinositido Fosfolipasa C/genética , Cultivo Primario de Células , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Estructura Terciaria de Proteína , Transducción de Señal , Trombina/metabolismo , Proteínas de Unión al GTP rap1/genética , ras-GRF1/genética
19.
Mol Cell ; 32(2): 169-79, 2008 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-18951085

RESUMEN

Elevated catecholamines in the heart evoke transcriptional activation of the Myocyte Enhancer Factor (MEF) pathway to induce a cellular response known as pathological myocardial hypertrophy. We have discovered that the A-Kinase Anchoring Protein (AKAP)-Lbc is upregulated in hypertrophic cardiomyocytes. It coordinates activation and movement of signaling proteins that initiate MEF2-mediated transcriptional reprogramming events. Live-cell imaging, fluorescent kinase activity reporters, and RNA interference techniques show that AKAP-Lbc couples activation of protein kinase D (PKD) with the phosphorylation-dependent nuclear export of the class II histone deacetylase HDAC5. These studies uncover a role for AKAP-Lbc in which increased expression of the anchoring protein selectively amplifies a signaling pathway that drives cardiac myocytes toward a pathophysiological outcome.


Asunto(s)
Proteínas de Anclaje a la Quinasa A/fisiología , Cardiomegalia/metabolismo , Factores de Intercambio de Guanina Nucleótido/fisiología , Proteínas Proto-Oncogénicas/fisiología , Transducción de Señal , Proteínas 14-3-3/metabolismo , Proteínas de Anclaje a la Quinasa A/genética , Proteínas de Anclaje a la Quinasa A/metabolismo , Transporte Activo de Núcleo Celular , Animales , Células COS , Línea Celular , Chlorocebus aethiops , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulación de la Expresión Génica , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Ventrículos Cardíacos/efectos de los fármacos , Histona Desacetilasas/metabolismo , Humanos , Factores de Transcripción MEF2 , Antígenos de Histocompatibilidad Menor , Modelos Biológicos , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Factores Reguladores Miogénicos/metabolismo , Fenilefrina/farmacología , Fosforilación , Proteína Quinasa C/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Interferencia de ARN , Ratas
20.
J Biol Chem ; 289(13): 8781-98, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24500718

RESUMEN

Phosphorylation of gap junction proteins, connexins, plays a role in global signaling events involving kinases. Connexin43 (Cx43), a ubiquitous and important connexin, has several phosphorylation sites for specific kinases. We appended an imaging reporter tag for the activity of the δ isoform of protein kinase C (PKCδ) to the carboxyl terminus of Cx43. The FRET signal of this reporter is inversely related to the phosphorylation of serine 368 of Cx43. By activating PKC with the phorbol ester phorbol 12,13-dibutyrate (PDBu) or a natural stimulant, UTP, time lapse live cell imaging movies indicated phosphorylated Ser-368 Cx43 separated into discrete domains within gap junctions and was internalized in small vesicles, after which it was degraded by lysosomes and proteasomes. Mutation of Ser-368 to an Ala eliminated the response to PDBu and changes in phosphorylation of the reporter. A phosphatase inhibitor, calyculin A, does not change this pattern, indicating PKC phosphorylation causes degradation of Cx43 without dephosphorylation, which is in accordance with current hypotheses that cells control their intercellular communication by a fast and constant turnover of connexins, using phosphorylation as part of this mechanism.


Asunto(s)
Conexina 43/metabolismo , Uniones Comunicantes/metabolismo , Movimiento , Proteína Quinasa C-delta/metabolismo , Proteolisis , Animales , Células COS , Chlorocebus aethiops , Conexina 43/química , Uniones Comunicantes/efectos de los fármacos , Células HeLa , Humanos , Movimiento/efectos de los fármacos , Ésteres del Forbol/farmacología , Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Fosforilación/efectos de los fármacos , Proteína Quinasa C-delta/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Transporte de Proteínas/efectos de los fármacos , Proteolisis/efectos de los fármacos , Serina/metabolismo
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