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1.
J Mol Cell Cardiol ; 64: 20-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23994159

RESUMEN

It is believed that the diabetic myocardium is refractory to cardioprotection by ischemic preconditioning (IPC) mainly because of impaired insulin signaling to phosphatidylinositol 3-kinase (PI3K) and protein kinase B (PKB or Akt). However, human as well as animal studies have clearly showed that the hearts of type 2 diabetic humans and animals may exhibit increased signaling through PI3K-Akt but yet are resistant to cardioprotection by IPC or ischemic post-conditioning. Therefore, this study was designed to determine whether activation of insulin signaling prior to IPC is detrimental for cardioprotection and to assess the role of insulin receptors (IRs) and Akt in mediating this effect. Wild-type (WT) hearts, hearts lacking IRs or hearts expressing an active form of Akt (myrAkt1) were perfused ex vivo using a Langendorff preparation and were subjected to IPC (3cycles of 5min ischemia followed by 5min reflow before 30min no flow ischemia and then by 45min reperfusion) in the presence or absence of 1nmol/L insulin. Interestingly, whereas insulin was protective against I/R (30min no flow ischemia and 45min reperfusion), it completely abolished cardioprotection by IPC in WT hearts but not in mice lacking insulin receptors (IRs) in cardiomyocytes (CIRKO) or in all cardiac cells (TIRKO). The suppression of IPC-mediated cardioprotection was mediated through downstream signaling to Akt and Gsk3ß. In addition, transgenic induction of Akt in the heart was sufficient to abrogate IPC even when insulin was absent, further confirming the involvement of Akt in insulin's suppression of cardioprotection by IPC. These data provide evidence that excessive insulin signaling to Akt is detrimental for cardioprotection by IPC and could explain the failure of the diabetic myocardium to precondition.


Asunto(s)
Insulina/metabolismo , Precondicionamiento Isquémico Miocárdico , Miocardio/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Cardiotónicos/metabolismo , Cardiotónicos/farmacología , Glucógeno/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Insulina/farmacología , Ácido Láctico/biosíntesis , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Proteínas Quinasas Activadas por Mitógenos , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/prevención & control , Miocardio/patología , Fosforilación , Receptor de Insulina/metabolismo , Transducción de Señal
2.
Front Endocrinol (Lausanne) ; 12: 720723, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335481

RESUMEN

Iodine-resistant cancers account for the vast majority of thyroid related mortality and, until recently, there were limited therapeutic options. However, over the last decade our understanding of the molecular foundation of thyroid function and carcinogenesis has driven the development of many novel therapeutics. These include FDA approved tyrosine kinase inhibitors and small molecular inhibitors of VEGFR, BRAF, MEK, NTRK and RET, which collectively have significantly changed the prognostic outlook for this patient population. Some therapeutics can re-sensitize de-differentiated cancers to iodine, allowing for radioactive iodine treatment and improved disease control. Remarkably, there is now an FDA approved treatment for BRAF-mutated patients with anaplastic thyroid cancer, previously considered invariably and rapidly fatal. The treatment landscape for iodine-resistant thyroid cancer is changing rapidly with many new targets, therapeutics, clinical trials, and approved treatments. We provide an up-to-date review of novel therapeutic options in the treatment of iodine-resistant thyroid cancer.


Asunto(s)
Radioisótopos de Yodo/uso terapéutico , Tolerancia a Radiación , Terapias en Investigación , Neoplasias de la Tiroides/terapia , Humanos , Tolerancia a Radiación/fisiología , Terapias en Investigación/métodos , Terapias en Investigación/tendencias , Neoplasias de la Tiroides/radioterapia , Insuficiencia del Tratamiento
3.
Otolaryngol Head Neck Surg ; 162(6): 888-896, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32093532

RESUMEN

OBJECTIVE: Advanced laryngeal squamous cell carcinoma remains associated with approximately 50% mortality at 5 years. Delivery of multimodality treatment remains critical to maximizing survival for this disease, but achieving this at a national level remains a difficult undertaking, particularly in under- and uninsured patients as well as minority patients. We sought to evaluate laryngeal cancer treatment delivery and clinical outcomes in a predominantly minority and underserved cohort of largely under- and uninsured patients in a county hospital. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care county hospital in Houston, Texas. SUBJECTS AND METHODS: Patients (N = 210) with a new diagnosis of laryngeal squamous cell carcinoma treated between 2005 and 2015 were included in a retrospective analysis of patient demographics, tumor and treatment characteristics, and oncologic outcomes. RESULTS: The majority of patients presented with advanced disease (T4 = 43%, N>0 = 45%). Treatment selection was compliant with National Comprehensive Cancer Network guidelines in 81% of cases, but 76% of patients who required adjuvant radiotherapy were unable to start it within 6 weeks postsurgery. Overall survival and disease-free survival were 52% and 63% for the entire cohort, respectively. Supraglottic subsite and nodal metastases were significantly associated with decreased overall survival and disease-free survival. Race/ethnicity and insurance status were not associated with worse oncologic outcomes. CONCLUSION: Under- and uninsured patients often present with advanced laryngeal cancer. Oncologic outcomes in this cohort of patients is similar to that of other published series. Moreover, tumor characteristics rather than demographic variables drive oncologic outcomes for the predominantly minority and underserved patients seeking care in our tertiary care county hospital.


Asunto(s)
Carcinoma de Células Escamosas/epidemiología , Neoplasias Laríngeas/epidemiología , Grupos Minoritarios , Estadificación de Neoplasias , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/terapia , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Texas/epidemiología
4.
Laryngoscope ; 130(7): 1733-1739, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31461171

RESUMEN

OBJECTIVES: Multiple population studies have shown racial discrepancies in head and neck cancer treatment and outcomes. We sought to characterize the impact of race on clinical outcomes for patients with early glottic squamous cell carcinoma (SCC) in a tertiary institution which provides equivalent access to care. METHODS: We retrospectively reviewed all early glottic (T1-T2) squamous cell carcinoma at a single institution, the Michael E. DeBakey Veterans' Administration Medical Center (MEDVAMC). Data collected included demographic information, primary and adjuvant treatment modalities, time to diagnosis, time to treatment, recurrences, recurrence treatment modality, secondary malignancies, recurrence-free survival (RFS), and overall survival (OS). RESULTS: One hundred seventeen patients with a primary diagnosis of T1-T2 glottic squamous cell carcinoma were included. Black and white patients demonstrated equivalent rates of recurrence, RFS, and OS. There was no significant difference in treatment delivery by race for all recorded parameters. T1b tumors were associated with an increased risk of recurrence which did not translate into a statistically significant decrease in RFS or OS. Surgical treatment was associated with increased recurrence but similar RFS and OS compared to radiation-based treatment. Secondary malignancies were common; 12% of patients were diagnosed with a second primary lung cancer during the study period. CONCLUSION: At our institution, race did not impact survival when access to care, treatment selection, and delivery are equivalent for early glottic SCC. Secondary lung cancer is a critical risk factor for mortality in this patient group and requires long-term surveillance and monitoring. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:1733-1739, 2020.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Manejo de la Enfermedad , Neoplasias Laríngeas/diagnóstico , Estadificación de Neoplasias , Medición de Riesgo/métodos , Veteranos/estadística & datos numéricos , Anciano , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/terapia , Terapia Combinada/métodos , Supervivencia sin Enfermedad , Femenino , Glotis , Humanos , Neoplasias Laríngeas/epidemiología , Neoplasias Laríngeas/terapia , Masculino , Persona de Mediana Edad , Morbilidad/tendencias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia/tendencias , Estados Unidos/epidemiología
5.
Laryngoscope ; 129(3): 699-703, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30284251

RESUMEN

BACKGROUND: Vocal fold movement impairment (VFMI) secondary to neuronal injury is a known risk after aortic surgery. Total arch replacement is technically challenging, and the incidence of vocal fold movement impairment secondary to neuronal injury after this surgery is unknown. This study examined the incidence of VFMI after total arch replacement and medialization treatment outcomes. STUDY DESIGN: Retrospective cohort study. METHODS: All patients who underwent total arch replacement at a tertiary care center over 11 years (2006-2017) were identified through an institutional database. End points included evidence of VFMI on flexible laryngoscopy, time to diagnosis, time to treatment, need for reintubation, and intensive care unit (ICU) and hospital length of stay. RESULTS: Of the 358 patients who underwent total arch replacement, 63 (20%) were diagnosed with VFMI during their initial inpatient stay. Fifty patients (79%) VFMIs were left-sided, nine (14%) were right-sided, and four (6%) were bilateral. Thirty-nine patients (62%) underwent inpatient vocal fold medialization: 28 (72%) by injection laryngoplasty and 11 (28%) by type 1 thyroplasty. Those with unilateral VFMI had longer ICU (8.9 days) and hospital (19.4 days) than those with no VFMI (5.7 and 16.1 days). Among patients with unilateral VFMI, those who underwent inpatient vocal fold medialization trended toward shorter ICU (6.2 vs. 14.4 days, P = .03) and hospital stays (20.1 vs. 23.3 days, P = .4) than patients who did not have a medialization procedure. CONCLUSION: The overall incidence of VFMI after total arch replacement in our series was 20%. Both the right and left vocal folds are potentially at risk from a total arch replacement; consequently, the distribution of injury in our cohort was more heterogeneous than in other series. LEVEL OF EVIDENCE: 3 Laryngoscope, 129:699-703, 2019.


Asunto(s)
Aorta Torácica/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Parálisis de los Pliegues Vocales/epidemiología , Parálisis de los Pliegues Vocales/cirugía , Estudios de Cohortes , Femenino , Humanos , Incidencia , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Traumatismos del Nervio Laríngeo Recurrente/complicaciones , Estudios Retrospectivos , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Parálisis de los Pliegues Vocales/etiología
6.
Artículo en Inglés | MEDLINE | ID: mdl-29204560

RESUMEN

OBJECTIVE: To investigate the contributions of envelope and fine-structure to the perception of timbre by cochlear implant (CI) users as compared to normal hearing (NH) listeners. METHODS: This was a prospective cohort comparison study. Normal hearing and cochlear implant patients were tested. Three experiments were performed in sound field using musical notes altered to affect the characteristic pitch of an instrument and the acoustic envelope. Experiment 1 assessed the ability to identify the instrument playing each note, while experiments 2 and 3 assessed the ability to discriminate the different stimuli. RESULTS: Normal hearing subjects performed better than CI subjects in all instrument identification tasks, reaching statistical significance for 4 of 5 stimulus conditions. Within the CI population, acoustic envelope modifications did not significantly affect instrument identification or discrimination. With envelope and pitch cues removed, fine structure discrimination performance was similar between normal hearing and CI users for the majority of conditions, but some specific instrument comparisons were significantly more challenging for CI users. CONCLUSIONS: Cochlear implant users perform significantly worse than normal hearing listeners on tasks of instrument identification. However, cochlear implant listeners can discriminate differences in envelope and some fine structure components of musical instrument sounds as well as normal hearing listeners. The results indicated that certain fine structure cues are important for cochlear implant users to make discrimination judgments, and therefore may affect interpretation toward associating with a specific instrument for identification.

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