Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Ann Surg ; 274(3): 434-440, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34132701

RESUMEN

OBJECTIVES: A courtesy author is an individual who has not met authorship criteria but is listed as an author. This practice is common and often seen as victimless. Because publications are used for funding and promotion decisions, it is critical to understand biases in this practice. METHODS: An anonymous survey was conducted from March to October 2020 of first and senior authors of publications from 2014 to 2015 in 8 surgical journals. Authors were surveyed about demographic data, practice setting, and courtesy author practices. RESULTS: Three hundred forty-one authors responded (16% response rate). 75% were from academic practice settings. 14% reported adding courtesy authors 5 or more times in the past year. Courtesy authors were more often male (80%, P = 0.023), older (75%), and of higher academic rank (65%) than first/senior authors. All author groups were >75% white. When a reason was reported, 46% added a courtesy author due to avoid retaliation; 64% to avoid awkwardness. 26% expected reciprocal authorship offers. 92% of respondents acknowledge understanding International Committee of Medical Journal Editors authorship criteria. Women were less common among those added from goodwill than those added from fear (P = 0.039.) When courtesy authors were of a lower rank than first/senior authors, they were nearly twice as likely to be female (P = 0.0056) or non-white (P = 0.0184.). CONCLUSION: Courtesy authors were more often male, older, and higher rank than first/senior authors. Fear of career consequences was a major motivator for including courtesy authors. Understanding the motivations and pressures leading to courtesy authorship will help to correct this practice.


Asunto(s)
Autoria , Cirugía General , Motivación , Publicaciones Periódicas como Asunto/estadística & datos numéricos , Edición/estadística & datos numéricos , Sexismo , Investigación Biomédica , Femenino , Humanos , Relaciones Interpersonales , Masculino , Encuestas y Cuestionarios
2.
Surgery ; 165(5): 1008-1013, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30777364

RESUMEN

BACKGROUND: Approximately 70% of breast cancer patients have residual disease after neoadjuvant chemotherapy. This study was designed to determine whether breast cancer cells with stemlike properties are present in residual disease after neoadjuvant chemotherapy and whether they exhibit oncogenic mutations. The presence of breast cancer cells with stemlike properties with specific mutations may help explain the poor prognosis associated with residual disease. METHODS: A total of 68 breast cancer specimens were collected at the time of mastectomy or lumpectomy. A total of 44 were chemotherapy naïve and 24 were collected as residual disease after neoadjuvant chemotherapy. Tumor cells were collected by fluorescence-activated cell sorting, with breast cancer cells with stemlike properties specifically identified using breast stem cell associated antibodies. Whole tumor specimens and fluorescence-activated cell sorting breast cancer cells with stemlike properties were analyzed for genetic mutations, including PIK3CA. RESULTS: Breast cancer cells with stemlike properties, demonstrating EpCAM-positive, CD44-positive, CD49f±, CD24± expression were present in chemotherapy-naïve tumors and residual disease. In both chemotherapy-naïve and residual disease specimens the highest frequency of PIK3CA mutations were detected in CD49f-CD24+ BCSCs (39% and 33%, respectively). PIK3CA mutations were detected in all stages of breast cancer (35%), in both chemotherapy naïve (39%) and residual disease (29%) and in both estrogen receptor positive (41%) and negative tumors (14%) (P = ns). Various PIK3CA mutations were identified in chemotherapy-naïve specimens versus residual disease specimens in both patient-paired and unpaired breast cancers. CONCLUSION: Breast cancer cells with stemlike properties with mutations in PIK3CA were present in chemotherapy-naïve breast cancers and residual disease after neoadjuvant chemotherapy. These results demonstrate that neoadjuvant chemotherapy does not completely eradicate PIK3CA-defective breast cancer cells with stemlike properties. Although these findings may help explain the poor clinical outcomes in patients with residual disease, they also identify breast cancer cells with stemlike-property targets for therapies.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias de la Mama/terapia , Mama/patología , Células Madre Neoplásicas/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Mama/efectos de los fármacos , Mama/cirugía , Neoplasias de la Mama/patología , Fosfatidilinositol 3-Quinasa Clase I/genética , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Femenino , Humanos , Mastectomía , Persona de Mediana Edad , Mutación , Terapia Neoadyuvante/métodos , Neoplasia Residual , Células Madre Neoplásicas/metabolismo , Resultado del Tratamiento
3.
Am J Surg ; 217(5): 932-936, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30635207

RESUMEN

BACKGROUND: Patients with carcinoid tumors are at risk for profound intraoperative hypotension known as carcinoid crisis, which catecholamines are traditionally believed to trigger. However, data supporting this are lacking. METHODS: Anesthesia records were retrospectively reviewed for carcinoid patients treated with vasopressors. Hemodynamics for those with crisis were compared between those who received ß-adrenergic agonists (B-AA) versus those who did not. RESULTS: Among 293 consecutive operations, 58 were marked by 161 crises. There was no significant difference in the incidence of paradoxical hypotension with B-AA compared to non-B-AA (p = 0.242). The maximum percent decrease in mean arterial pressure following drug administration was significantly greater in those patients treated with non-B-AA than with B-AA (31.6% vs. 12.5%, p < 0.0001). There were no differences in crisis duration (p = 0.257) or postoperative complication rate (p = 0.896). CONCLUSIONS: ß-Adrenergic agonist use was not associated with paradoxical hypotension, prolonged carcinoid crisis, or postoperative complications in patients with intraoperative carcinoid crisis.


Asunto(s)
Agonistas Adrenérgicos beta/uso terapéutico , Tumor Carcinoide/cirugía , Hipotensión/tratamiento farmacológico , Complicaciones Intraoperatorias/tratamiento farmacológico , Vasoconstrictores/uso terapéutico , Neoplasias del Sistema Digestivo/cirugía , Efedrina/uso terapéutico , Epinefrina/uso terapéutico , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/uso terapéutico , Fenilefrina/uso terapéutico , Complicaciones Posoperatorias , Estudios Retrospectivos
4.
Surgery ; 165(1): 158-165, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30415870

RESUMEN

BACKGROUND: Sudden massive release of serotonin, histamine, kallikrein, and bradykinin is postulated to cause an intraoperative carcinoid crisis. The exact roles of each of these possible agents, however, remain unknown. Optimal treatment will require an improved understanding of the pathophysiology of the carcinoid crisis. METHODS: Carcinoid patients with liver metastases undergoing elective abdominal operations were studied prospectively, using intraoperative, transesophageal echocardiography, pulmonary artery catheterization, and intraoperative blood collection. Serotonin, histamine, kallikrein, and bradykinin levels were analyzed by enzyme-linked immunosorbent assay. RESULTS: Of 46 patients studied, 16 had intraoperative hypotensive crises. Preincision serotonin levels were greater in patients who had crises (1,064 vs 453 ng/mL, P = .0064). Preincision hormone profiles were otherwise diverse. Cardiac function on transesophageal echocardiography during the crisis was normal, but intracardiac hypovolemia was observed consistently. Pulmonary artery pressure decreased during crises (P = .025). Linear regression of preincision serotonin levels showed a positive relationship with mid-crisis cardiac index (r = 0.73, P = .017) and a negative relationship with systemic vascular resistance (r=-0.61, P = .015). There were no statistically significant increases of serotonin, histamine, kallikrein, or bradykinin levels during the crises. CONCLUSION: The pathophysiology of carcinoid crisis appears consistent with distributive shock. Hormonal secretion from carcinoid tumors varies widely, but increased preincision serotonin levels correlate with crises and with hemodynamic parameters during the crises. Statistically significant increases of serotonin, histamine, kallikrein, or bradykinin during the crises were not observed.


Asunto(s)
Hipotensión/fisiopatología , Hipovolemia/fisiopatología , Síndrome Carcinoide Maligno/fisiopatología , Arteria Pulmonar/fisiopatología , Serotonina/sangre , Bradiquinina/sangre , Tumor Carcinoide/fisiopatología , Tumor Carcinoide/cirugía , Ecocardiografía Transesofágica , Femenino , Histamina/sangre , Humanos , Neoplasias Intestinales/fisiopatología , Neoplasias Intestinales/cirugía , Complicaciones Intraoperatorias , Calicreínas/sangre , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/fisiopatología , Neoplasias Pulmonares/cirugía , Masculino , Síndrome Carcinoide Maligno/sangre , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos
5.
Surgery ; 159(1): 358-65, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26603846

RESUMEN

BACKGROUND: Operations and anesthesia in carcinoid patients can provoke carcinoid crises, which can have serious sequelae, including death. Prophylactic octreotide is recommended to prevent crises. Recommended prophylaxis regimens vary from octreotide long-acting repeatable to preoperative bolus to continuous octreotide infusion; however, efficacy data are lacking. We have shown previously that crises correlated with major complications and that octreotide long-acting repeatable and preoperative bolus failed to prevent crises. This study examines the impact of continuous octreotide infusion. METHODS: A total of 127 patients (71% with liver metastases, 74% with carcinoid syndrome) who underwent 150 operations with continuous octreotide infusions were enrolled in this prospective case series. Our main outcome measures were the occurrence of intraoperative carcinoid crises and post-operative complications. RESULTS: Crises occurred at a rate of 30% as compared with 24% in our previous series, which examined the impact of preoperative octreotide bolus. Crises were significantly associated with the presence of hepatic metastases (P = .02) or history of carcinoid syndrome (P = .006), although neither was required for crises. Prompt vasopressor treatment shortened the mean duration of hypotension to 8.7 minutes, compared with 19 minutes in our prior series. Crises no longer correlated with major complications (P = .481) unless instability persisted for greater than 10 minutes (P = .011). CONCLUSION: Octreotide infusions do not prevent intraoperative crises. Patients without liver metastases or carcinoid syndrome can have intraoperative crises. Postoperative complications can be decreased by reducing the duration of crises. Further study is needed to determine how best to shorten hemodynamic instability during crises.


Asunto(s)
Antineoplásicos Hormonales/administración & dosificación , Tumor Carcinoide/cirugía , Neoplasias Hepáticas/cirugía , Síndrome Carcinoide Maligno/prevención & control , Octreótido/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Tumor Carcinoide/complicaciones , Tumor Carcinoide/patología , Femenino , Humanos , Infusiones Intravenosas , Inyecciones Intravenosas , Cuidados Intraoperatorios , Periodo Intraoperatorio , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/secundario , Masculino , Síndrome Carcinoide Maligno/etiología , Persona de Mediana Edad , Adulto Joven
6.
Stem Cell Res Ther ; 6: 157, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26316122

RESUMEN

INTRODUCTION: Cancers are believed to adapt to continual changes in glucose and oxygen availability by relying almost exclusively on glycolytic metabolism for energy (i.e. the Warburg effect). The process by which breast cancers sustain growth in avascular tissue is thought to be mediated via aberrant hypoxia response with ensuing shifts in glycolytic metabolism. Given their role in initiating and perpetuating tumors, we sought to determine whether breast cancer stem and progenitor cells play an instrumental role in this adaptive metabolic response. METHODS: Breast cancer stem/progenitor cells were isolated from invasive ductal carcinomas, and benign stem cells (SC) were isolated from reduction mammoplasty tissues. Relative expression of 33 genes involved in hypoxia and glucose metabolism was evaluated in flow cytometrically isolated stem and progenitor cell populations. Significance between cohorts and cell populations was determined using Student's 2-tailed t test. RESULTS: While benign stem/progenitor cells exhibited few significant inter-group differences in expression of genes involved in hypoxia regulation or glucose metabolism, breast cancer stem/progenitor cells demonstrated significant inter-group variability. Breast cancer stem/progenitor cells adapted to microenvironments through changes in stem cell numbers and transcription of glycolytic genes. One of four breast cancer stem/progenitor cells subpopulations exhibited an aerobic glycolysis gene expression signature. This subpopulation comprises the majority of the tumor and therefore best reflects invasive ductal carcinoma tumor biology. Although PI3K/AKT mutations are associated with increased proliferation of breast cancer cells, mutations in breast cancer stem/progenitor cells subpopulations did not correlate with changes in metabolic gene expression. CONCLUSIONS: The adaptive capacity of breast cancer stem/progenitor cells may enable tumors to survive variable conditions encountered during progressive stages of cancer growth.


Asunto(s)
Neoplasias de la Mama/genética , Glucólisis , Células Madre Neoplásicas/metabolismo , Transcriptoma , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Células Cultivadas , Femenino , Humanos , Células MCF-7 , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA