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1.
Laryngoscope ; 133(12): 3389-3395, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37194665

RESUMEN

INTRODUCTION: To assess the association between time to surgery (TTS) and survival in sinonasal squamous cell carcinoma patients (SSCC). METHODS: We queried the 2004-2016 National Cancer Database for all cases of adult SSCC undergoing primary surgical treatment. Patients with missing TTS information were excluded. We conducted a multivariate analysis of patient demographic and clinicopathological characteristics' effect on overall survival (OS) using a Cox proportional hazards model enhanced with cubic spline non-linear approximation. Bootstrapping methods were utilized to detect the aggregate risk of TTS delay on patient OS. RESULTS: A total of 2,881 patients met the inclusion criteria. The majority of patients were male (63.5%), White (86.3%), and over the age of 60 (58.4%). Parametric cubic spline approximation Cox hazard model detected a non-linear association between patient OS and TTS below 30 days with the lowest risk occurring at 18 days and steadily increasing subsequently. To analyze the aggregate risk and identify the optimal TTS cut-off after 30 days of surgical delay, the cohort sample was bootstrapped and dichotomized. The largest increase in aggregated risk was identified at 59 days (Hazards Ratio [HR] = 1.006 [0.839-1.084], p = 0.003). 60 days were used as the optimal TTS cut-off for analyzing the survival rate using the Cox proportional hazard model. Undergoing surgery within 60 days translated to a 14.6% decreased chance of death (HR: 0.854 [0.83-0.96]). CONCLUSIONS: Increasing TTS is associated with worse overall survival in patients with SSCC. Our study suggests that surgery should be done within 60 days to achieve optimal survival results. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:3389-3395, 2023.


Asunto(s)
Neoplasias de los Senos Paranasales , Adulto , Humanos , Masculino , Femenino , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias de los Senos Paranasales/patología , Tasa de Supervivencia
2.
Head Neck ; 45(5): 1113-1121, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36859787

RESUMEN

BACKGROUND: Opioids are commonly used to manage the pain of head and neck (HN) cancer patients. METHODS: Retrospective cohort of graduates from American Head and Neck Society accredited fellowships from 1997 to 2018. The Center for Medicare and Medicaid Services Part D Provider Utilization and Payment database 2014-2019 was cross-referenced with provider names to identify opioid prescription trends. RESULTS: From 2014 to 2019, there was no significant difference in the average number of opioid beneficiaries per provider (18.02 vs. 18.10, p = 0.586) or opioid claims per provider (28.06 vs. 26.73, p = 0.708). The average total opioid day supply per beneficiary declined from 11.09 to 7.05 days from 2014 to 2019 (p < 0.001). In 2019, providers in the Northeast had the lowest prescribed opioid day supply (3.67 days) compared to those from the South who had the highest (10.32 days). CONCLUSIONS: Opioid prescription length has significantly declined among HN surgeons, with variations across geographic regions.


Asunto(s)
Analgésicos Opioides , Becas , Humanos , Estados Unidos , Anciano , Analgésicos Opioides/uso terapéutico , Estudios Retrospectivos , Medicare , Pautas de la Práctica en Medicina , Prescripciones de Medicamentos
3.
Otolaryngol Head Neck Surg ; 168(6): 1338-1345, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36939404

RESUMEN

OBJECTIVE: This study reviews the presentation, management, and outcomes of patients with rhinolithiasis. DATA SOURCES: An electronic database search of PubMed, SCOPUS, CINAHL, and the Cochrane Library was performed in accordance with the PRISMA 2020 updated guidelines for reporting systematic reviews. REVIEW METHODS: Case reports and case series published from 2004 to 2020 were included. Data collected included patient demographics, clinical symptoms at presentation, diagnosis, treatment, complications, and follow-up. Relevant descriptive statistics were computed using Microsoft Excel 2013 (Microsoft Corp). RESULTS: Fifty-five case reports and five case series were included (n = 122). The majority were female (60.7%). The mean age was 29.4 years (range, 4-80 years). The most common symptoms were rhinorrhea (81.1%), nasal obstruction (79.5%), nasal malodor (38.5%), and headache (27.9%). Computed tomography imaging was obtained in 109 (91.5%) cases. Concurrent rhinosinusitis (35.2%) and deviated nasal septum (28.7%) were commonly identified. Rhinoliths were commonly found in the right nostril (52.5%) and in between the inferior turbinate and nasal septum (26.9%). All rhinoliths were fully excised using endoscopic sinonasal surgery, accompanied by a septoplasty (9.2%). The nidus was identified in 27 (22.2%) patients. There were no recurrences or complications over an average follow-up of 8.5 months (range, 0.25-36 months). CONCLUSION: Rhinolithiasis is an uncommon entity of the nasal cavity and should be suspected in patients with long-standing unilateral nasal obstruction, rhinorrhea, and nasal malodor. Rigid nasal endoscopy and endoscopic sinonasal surgery are the most important methods for diagnosis and treatment, respectively.


Asunto(s)
Litiasis , Obstrucción Nasal , Enfermedades Nasales , Humanos , Masculino , Femenino , Adulto , Enfermedades Nasales/cirugía , Obstrucción Nasal/etiología , Rinorrea , Endoscopía/métodos
4.
Urol Oncol ; 41(5): 253.e11-253.e20, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36813612

RESUMEN

CDK4/6 inhibitors have proven their potency for the treatment of cancer but only in combination with hormone or targeted therapies. The aim of this study was the identification of molecules that are involved in response mechanisms to CDK4/6 inhibitors and the development of novel combination therapies with corresponding inhibitors in bladder cancer. Genes of response to therapy and genes that confer resistance to the CDK4/6 inhibitor palbociclib were identified by performing an analysis of published literature and own published data using a CRISPR-dCas9 genome wide gain of function screen. Genes that were down-regulated upon treatment were compared with genes that confer resistance when up-regulated. Two of the top 5 genes were validated by quantitative PCR and western blotting upon treatment with palbociclib in the bladder cancer cell lines T24, RT112 and UMUC3. As inhibitors for combination therapy, we used ciprofloxacin, paprotrain, ispinesib and SR31527. Analysis of synergy was done using the "zero interaction potency" model. Cell growth was examined using sulforhodamine B staining. A list of genes that met the requirements for inclusion in the study was generated from 7 publications. Of the 5 most relevant genes, MCM6 and KIFC1 were chosen and their down-regulation upon treatment with palbociclib was confirmed by qPCR and immunoblotting. The combination of inhibitors against both, KIFC1 and MCM6 with PD resulted in a synergistic inhibition of cell growth. We have identified 2 molecular targets whose inhibition has promising potential for effective combination therapies with the CDK4/6 inhibitor palbociclib.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Vejiga Urinaria , Humanos , Femenino , Línea Celular Tumoral , Quinasa 4 Dependiente de la Ciclina/genética , Quinasa 4 Dependiente de la Ciclina/farmacología , Proliferación Celular , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Ciclo Celular , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico
5.
J Thromb Haemost ; 21(5): 1366-1380, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36738826

RESUMEN

BACKGROUND: Vascular activation is characterized by increased proinflammatory, pro thrombotic, and proadhesive signaling. Several chronic and acute conditions, including Bcr-abl-negative myeloproliferative neoplasms (MPNs), graft-vs-host disease, and COVID-19 have been noted to have increased activation of the janus kinase (JAK)-signal transducer and downstream activator of transcription (STAT) pathways. Two notable inhibitors of the JAK-STAT pathway are ruxolitinib (JAK1/2 inhibitor) and fedratinib (JAK2 inhibitor), which are currently used to treat MPN patients. However, in some conditions, it has been noted that JAK inhibitors can increase the risk of thromboembolic complications. OBJECTIVES: We sought to define the anti-inflammatory and antithrombotic effects of JAK-STAT inhibitors in vascular endothelial cells. METHODS: We assessed endothelial activation in the presence or absence of ruxolitinib or fedratinib by using immunoblots, immunofluorescence, qRT-PCR, and function coagulation assays. Finally, we used endothelialized microfluidics perfused with blood from normal and JAK2V617F+ individuals to evaluate whether ruxolitinib and fedratinib changed cell adhesion. RESULTS: We found that both ruxolitinib and fedratinib reduced endothelial cell phospho-STAT1 and STAT3 signaling and attenuated nuclear phospho-NK-κB and phospho-c-Jun localization. JAK-STAT inhibition also limited secretion of proadhesive and procoagulant P-selectin and von Willebrand factor and proinflammatory IL-6. Likewise, we found that JAK-STAT inhibition reduced endothelial tissue factor and urokinase plasminogen activator expression and activity. CONCLUSIONS: By using endothelialized microfluidics perfused with whole blood samples, we demonstrated that endothelial treatment with JAK-STAT inhibitors prevented rolling of both healthy control and JAK2V617F MPN leukocytes. Together, these findings demonstrate that JAK-STAT inhibitors reduce the upregulation of critical prothrombotic pathways and prevent increased leukocyte-endothelial adhesion.


Asunto(s)
COVID-19 , Quinasas Janus , Humanos , Quinasas Janus/metabolismo , Quinasas Janus/farmacología , Transducción de Señal , Células Endoteliales/metabolismo , Factores de Transcripción STAT/metabolismo , Factores de Transcripción STAT/farmacología , Janus Quinasa 2 , Leucocitos/metabolismo
6.
Chembiochem ; 23(3): e202100614, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-34881485

RESUMEN

Cycles of dehydration and rehydration could have enabled formation of peptides and RNA in otherwise unfavorable conditions on the early Earth. Development of the first protocells would have hinged upon colocalization of these biopolymers with fatty acid membranes. Using atomic force microscopy, we find that a prebiotic fatty acid (decanoic acid) forms stacks of membranes after dehydration. Using LC-MS-MS (liquid chromatography-tandem mass spectrometry) with isotope internal standards, we measure the rate of formation of serine dipeptides. We find that dipeptides form during dehydration at moderate temperatures (55 °C) at least as fast in the presence of decanoic acid membranes as in the absence of membranes. Our results are consistent with the hypothesis that protocells could have formed within evaporating environments on the early Earth.


Asunto(s)
Ácidos Decanoicos/química , Péptidos/síntesis química , Deshidratación , Péptidos/química , Conformación Proteica , Temperatura
7.
Ear Nose Throat J ; 101(6): 379-385, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32921181

RESUMEN

INTRODUCTION: While the cochleotoxicity of cisplatin has been well investigated, less is known about the effects of platinum-based chemotherapy on the vestibular system. In particular, there is a lack of prospective studies using modern laboratory vestibular testing that examine the effects of cisplatin on the semicircular canals and on the otolith organs. The aim of the present study was, therefore, to investigate the vestibulotoxic effect of cisplatin in patients with head and neck tumors who are undergoing chemoradiation. METHODS: Forty-five patients undergoing cisplatin-based chemoradiation for head and neck cancer received a vestibular assessment consisting of anamnesis, a horizontal video head impulse test (vHIT), ocular and cervical vestibular evoked myogenic potential testing, as well as pure tone audiometry. This assessment was performed before therapy, 6 weeks after therapy, and 3 months after therapy. RESULTS: Video head impulse test showed a significantly reduced median gain 6 weeks after chemoradiation. In addition, significantly more refixational saccades could be detected after therapy. Vestibular evoked myogenic potential testing results also revealed significant changes, whereas pure tone audiometry did not. None of the patients mentioned "dizziness" during the follow-up examinations. CONCLUSION: We demonstrated a vestibulotoxic effect of cisplatin-based chemoradiation in patients with head and neck cancer. Future studies are needed to better understand cisplatin-induced vestibulotoxicity and to identify possible vestibuloprotective substances. Still, before and after chemoradiation, patients should undergo not only auditory testing but also vestibular testing in order to detect potential vestibular loss as soon as possible and to quickly initiate vestibular physiotherapy.


Asunto(s)
Neoplasias de Cabeza y Cuello , Potenciales Vestibulares Miogénicos Evocados , Vestíbulo del Laberinto , Cisplatino/efectos adversos , Prueba de Impulso Cefálico/métodos , Neoplasias de Cabeza y Cuello/terapia , Humanos , Canales Semicirculares , Potenciales Vestibulares Miogénicos Evocados/fisiología
9.
J Womens Health (Larchmt) ; 29(12): 1540-1546, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32364816

RESUMEN

Background: Childhood abuse has been associated with poor health outcomes in adulthood. However, the physiologic pathways by which abuse is linked to health are not fully elucidated. Inflammation plays a significant role in the pathophysiology of multiple chronic diseases. We tested whether childhood trauma exposure was related to increased systemic inflammation in midlife women. Materials and Methods: Participants were 304 nonsmoking perimenopausal and postmenopausal women aged 40 to 60 years and free of cardiovascular disease. They completed questionnaires assessing psychosocial and behavioral factors, including childhood trauma, anthropometric measures, wrist actigraphy sleep measurements, and a fasting blood draw for inflammatory markers high-sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6). Associations between childhood trauma and inflammatory markers were tested in linear regression models controlling for age, race/ethnicity, education, body mass index, anti-inflammatory medication use, and alcohol consumption. Other covariates considered included sleep continuity and depressive symptoms. Results: A total of 44.8% of the sample experienced at least one type of childhood abuse/neglect. Women with a history of emotional abuse had higher IL-6 levels than women without this history in multivariate models (ß = 0.077, standard error = 0.032, p = 0.017). Results were not accounted for by covariates and persisted additionally controlling for depressive symptoms and sleep. Childhood abuse/neglect was not related to hsCRP. Conclusions: Childhood emotional abuse was associated with higher levels of IL-6 in midlife women. Assessing childhood trauma exposure along with inflammatory markers may be important for the development of prevention strategies at midlife to prevent chronic diseases later in life.


Asunto(s)
Adultos Sobrevivientes del Maltrato a los Niños , Proteína C-Reactiva/análisis , Inflamación/etiología , Interleucina-6/sangre , Sueño/fisiología , Actigrafía , Adulto , Biomarcadores/sangre , Niño , Maltrato a los Niños , Femenino , Humanos , Inflamación/sangre , Interleucina-6/metabolismo , Persona de Mediana Edad , Perimenopausia , Posmenopausia
10.
Radiother Oncol ; 152: 196-202, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31973882

RESUMEN

BACKGROUND AND PURPOSE: Providing evidence for radiotherapy (RT)-induced effects on cardiac implantable electric devices (CIEDs) with focus on flattening filter free-volumetric modulated arc therapy (FFF-VMAT) at 6 and 10 MV as well as 3D-conformal radiotherapy (3D-CRT) at 18 MV. MATERIALS AND METHODS: 68 CIEDs (64 implantable cardioverter-defibrillators (ICDs) and 4 cardiac pacemakers (PMs)) were located on the left chest position on a slab phantom and irradiated under telemetrical surveillance either directly, or distant to 3D-CRT or FFF-VMAT, dose-rate 2500 cGy/min, and target dose of 150 Gy. Devices were placed within, close by (2.5 cm and 5 cm), and distant (35 cm) to the radiation field. Scatter radiation (SR) and photon neutrons (PN) were recorded. CIEDs were investigated in following groups: 1a) 18 MV 3D-CRT - 4 ICDs/4 PMs out of radiation field, 1b) 18 MV open field - 4 ICDs/4 PMs within radiation field, 2) 6 MV FFF-VMAT, 15 ICDs in 35 cm distance to VMAT, 3) 10 MV-FFF VMAT, 15 ICDs in 35 cm distance to VMAT, 4) 6 MV FFF-VMAT, 15 ICDs in 2.5 cm distance to VMAT, 5) 10 MV FFF-VMAT, 15 ICDs in 2.5 cm distance to VMAT. RESULTS: No incidents occurred at 6 MV FFF. 10 MV FFF-VMAT and 18 MV 3D-CRT resulted in data loss, reset, and erroneous sensing with inhibition of pacing (leading to inadequate defibrillation) in 8/34 ICDs and 2/4 PMs which were not located within radiation. Direct radiation triggered instantaneous defibrillation in 3/4 ICDs. CONCLUSIONS: 6 MV FFF-VMAT is safe even at high dose-rates of 2500 cGy/min, regardless whether CIEDs are located close (2.5 cm) or distant (35 cm) to the radiation beam. CIEDs should never be placed within radiation and energy should always be limited to 6 MV. At 6 MV, VMAT at high dose-rates can be used to treat tumors, which are located close to CIEDs.


Asunto(s)
Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Humanos , Neutrones , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos
11.
Front Immunol ; 11: 613278, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33542720

RESUMEN

Heme, released from red blood cells in sickle cell disease (SCD), interacts with toll-like receptor 4 (TLR4) to activate NF-κB leading to the production of cytokines and adhesion molecules which promote inflammation, pain, and vaso-occlusion. In SCD, TLR4 inhibition has been shown to modulate heme-induced microvascular stasis and lung injury. We sought to delineate the role of endothelial verses hematopoietic TLR4 in SCD by developing a TLR4 null transgenic sickle mouse. We bred a global Tlr4-/- deficiency state into Townes-AA mice expressing normal human adult hemoglobin A and Townes-SS mice expressing sickle hemoglobin S. SS-Tlr4-/- had similar complete blood counts and serum chemistries as SS-Tlr4+/+ mice. However, SS-Tlr4-/- mice developed significantly less microvascular stasis in dorsal skin fold chambers than SS-Tlr4+/+ mice in response to challenges with heme, lipopolysaccharide (LPS), and hypoxia/reoxygenation (H/R). To define a potential mechanism for decreased microvascular stasis in SS-Tlr4-/- mice, we measured pro-inflammatory NF-κB and adhesion molecules in livers post-heme challenge. Compared to heme-challenged SS-Tlr4+/+ livers, SS-Tlr4-/- livers had lower adhesion molecule and cytokine mRNAs, NF-κB phospho-p65, and adhesion molecule protein expression. Furthermore, lung P-selectin and von Willebrand factor immunostaining was reduced. Next, to establish if endothelial or hematopoietic cell TLR4 signaling is critical to vaso-occlusive physiology, we created chimeric mice by transplanting SS-Tlr4-/- or SS-Tlr4+/+ bone marrow into AA-Tlr4-/- or AA-Tlr4+/+ recipients. Hemin-stimulated microvascular stasis was significantly decreased when the recipient was AA-Tlr4-/- . These data demonstrate that endothelial, but not hematopoietic, TLR4 expression is necessary to initiate vaso-occlusive physiology in SS mice.


Asunto(s)
Anemia de Células Falciformes/metabolismo , Endotelio/metabolismo , Hemoglobina A/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Eritrocitos/metabolismo , Femenino , Hematopoyesis/fisiología , Hemo/metabolismo , Hemoglobina Falciforme/metabolismo , Humanos , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microvasos , FN-kappa B/metabolismo , Transducción de Señal/fisiología , Factor de Transcripción ReIA/metabolismo
12.
Chem Sci ; 10(11): 3231-3236, 2019 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-30996906

RESUMEN

We have developed a nickel-catalyzed hydroarylation of alkenes using aryl halides as coupling partners. Excellent anti-Markovnikov selectivity is achieved with aryl-substituted alkenes and enol ethers. We also show that hydroarylation occurs with alkyl substituted alkenes to yield linear products. Preliminary examination of the reaction mechanism suggests irreversible hydrometallation as the selectivity determining step of the hydroarylation.

13.
Gen Hosp Psychiatry ; 60: 141-147, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31030966

RESUMEN

OBJECTIVES: Due to improvements in earlier detection and expansions in available treatments, the number of individuals surviving with cancer is steadily increasing. Sexual dysfunction is a common and often persistent complication for cancer survivors, affecting >60% of women diagnosed with cancer. Although highly prevalent, issues related to sexual health are often not addressed among survivors, with women reporting less discussion with providers compared to men. METHODS: In this narrative review, we present a case series of three women seen in a psycho-oncology clinic who experienced sexual dysfunction following a cancer diagnosis. We then review existing literature on the presentation and management of sexual issues associated with cancer and its treatment. RESULTS: The three cases highlight different mechanisms of sexual dysfunction after cancer, including anatomic changes, hormonal alterations, psychiatric conditions and medication side effects. The literature review includes discussion of the prevalence and course of sexual dysfunction in female cancer survivors. Tools for screening and assessment are then reviewed, as well as contributing factors and common presenting symptoms. We conclude with a discussion of both pharmacologic and non-pharmacologic approaches to management. CONCLUSIONS: Despite its high prevalence and considerable impact on quality of life, the complication of sexual dysfunction after cancer diagnosis and treatment is still under recognized and undertreated. Improving awareness, communication, and screening, as well as appropriate referral to treatment, could have a profound impact on the ever growing number of women surviving with cancer with sexual health concerns.


Asunto(s)
Neoplasias de la Mama/terapia , Supervivientes de Cáncer , Disfunciones Sexuales Fisiológicas , Neoplasias Urogenitales/terapia , Adulto , Femenino , Humanos , Persona de Mediana Edad , Disfunciones Sexuales Fisiológicas/diagnóstico , Disfunciones Sexuales Fisiológicas/etiología , Disfunciones Sexuales Fisiológicas/terapia
14.
Theranostics ; 8(12): 3400-3407, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29930738

RESUMEN

The detection and treatment monitoring of inflammatory states remain challenging in part due to the multifactorial mechanisms of immune activation and spectrum of clinical manifestations. Currently, diagnostic strategies tend to be subjective and limited quantitative tools exist to monitor optimal treatment strategies. Pro-inflammatory M1 polarized macrophages exhibit a distinct metabolic glycolytic phenotype compared to the continuum of M2 polarization states. In the present study, the distinct metabolic phenotypes of resting and activated macrophages were successfully characterized and quantified using hyperpolarized carbon-13 (13C) labeled pyruvate and its metabolic products, i.e. lactate, as a biomarker of resting, disease and treated states. Methods: Mouse macrophage J774A.1 cells were used as a model system in an NMR compatible bioreactor to facilitate dynamic hyperpolarized 13C measurements. The glycolytic metabolism of the cells in the quiescent or resting state were compared with macrophages stimulated by lipopolysaccharide, a classical M1 activator using hyperpolarized 13C labeled pyruvate. Additionally, the activated macrophages were also treated with a non-steroidal anti-inflammatory drug to assess the changes in hyperpolarized lactate signal. The hyperpolarized lactate signals were then correlated using biochemical and molecular assays. Results: We first validated our model system of inflammatory cells by the hallmarks of M1 polarization using steady state metabolic profiling with high resolution NMR in conjunction with nitric oxide Greiss assay, enzyme activity, and mRNA expression. Subsequently, we clearly showed that the cutting edge technology of hyperpolarized 13C NMR can be used to detect elevated lactate levels in M1 polarized macrophages in comparison to control and non-steroidal anti-inflammatory drug treated M2 states. Conclusion: Hyperpolarized 13C lactate has the potential to serve as a biomarker to non-invasively detect and quantify pro-inflammatory state of immune regulatory cells and its response to therapy.


Asunto(s)
Isótopos de Carbono/análisis , Inflamación/diagnóstico , Inflamación/patología , Ácido Láctico/metabolismo , Macrófagos/metabolismo , Ácido Pirúvico/metabolismo , Animales , Biotransformación , Línea Celular , Glucólisis , Factores Inmunológicos/metabolismo , Marcaje Isotópico , Lipopolisacáridos/metabolismo , Activación de Macrófagos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Ratones
15.
PLoS One ; 13(4): e0196455, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29694434

RESUMEN

During hemolysis, hemoglobin and heme released from red blood cells promote oxidative stress, inflammation and thrombosis. Plasma haptoglobin and hemopexin scavenge free hemoglobin and heme, respectively, but can be depleted in hemolytic states. Haptoglobin and hemopexin supplementation protect tissues, including the vasculature, liver and kidneys. It is widely assumed that these protective effects are due primarily to hemoglobin and heme clearance from the vasculature. However, this simple assumption does not account for the consequent cytoprotective adaptation seen in cells and organs. To further address the mechanism, we used a hyperhemolytic murine model (Townes-SS) of sickle cell disease to examine cellular responses to haptoglobin and hemopexin supplementation. A single infusion of haptoglobin or hemopexin (± equimolar hemoglobin) in SS-mice increased heme oxygenase-1 (HO-1) in the liver, kidney and skin several fold within 1 hour and decreased nuclear NF-ĸB phospho-p65, and vaso-occlusion for 48 hours after infusion. Plasma hemoglobin and heme levels were not significantly changed 1 hour after infusion of haptoglobin or hemopexin. Haptoglobin and hemopexin also inhibited hypoxia/reoxygenation and lipopolysaccharide-induced vaso-occlusion in SS-mice. Inhibition of HO-1 activity with tin protoporphyrin blocked the protections afforded by haptoglobin and hemopexin in SS-mice. The HO-1 reaction product carbon monoxide, fully restored the protection, in part by inhibiting Weibel-Palade body mobilization of P-selectin and von Willebrand factor to endothelial cell surfaces. Thus, the mechanism by which haptoglobin and hemopexin supplementation in hyperhemolytic SS-mice induces cytoprotective cellular responses is linked to increased HO-1 activity.


Asunto(s)
Anemia de Células Falciformes/prevención & control , Haptoglobinas/uso terapéutico , Hemo-Oxigenasa 1/metabolismo , Hemopexina/uso terapéutico , Inflamación/prevención & control , Aldehídos/análisis , Anemia de Células Falciformes/patología , Animales , Monóxido de Carbono/farmacología , Citocinas/análisis , Modelos Animales de Enfermedad , Femenino , Expresión Génica/efectos de los fármacos , Haptoglobinas/farmacología , Hemopexina/farmacología , Molécula 1 de Adhesión Intercelular , Masculino , Metaloporfirinas/farmacología , Ratones , Microsomas Hepáticos/metabolismo , Protoporfirinas/farmacología , Piel/metabolismo , Piel/patología , Factor de Transcripción ReIA/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo
16.
Br J Haematol ; 175(4): 714-723, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27507623

RESUMEN

There is growing evidence that extracellular haemoglobin and haem mediate inflammatory and oxidative damage in sickle cell disease. Haptoglobin (Hp), the scavenger for free haemoglobin, is depleted in most patients with sickle cell disease due to chronic haemolysis. Although single infusions of Hp can ameliorate vaso-occlusion in mouse models of sickle cell disease, prior studies have not examined the therapeutic benefits of more chronic Hp dosing on sickle cell disease manifestations. In the present study, we explored the effect of Hp treatment over a 3-month period in sickle mice at two dosing regimens: the first at a moderate dose of 200 mg/kg thrice weekly and the second at a higher dose of 400 mg/kg thrice weekly. We found that only the higher dosing regimen resulted in increased haem-oxygenase-1 and heavy chain ferritin (H-ferritin) expression and decreased iron deposition in the kidney. Despite the decreased kidney iron deposition following Hp treatment, there was no significant improvement in kidney function. However, there was a nearly significant trend towards decreased liver infarction.


Asunto(s)
Anemia de Células Falciformes/metabolismo , Apoferritinas/metabolismo , Haptoglobinas/farmacología , Hierro/metabolismo , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/genética , Animales , Apoferritinas/genética , Recuento de Células Sanguíneas , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Haptoglobinas/administración & dosificación , Haptoglobinas/efectos adversos , Haptoglobinas/farmacocinética , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Enfermedades Renales/etiología , Enfermedades Renales/fisiopatología , Masculino , Ratones , Ratones Transgénicos , Resultado del Tratamiento
17.
Proc Natl Acad Sci U S A ; 113(16): 4464-9, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27035983

RESUMEN

Pancreatic neuroendocrine tumors (PanNETs) are a type of pancreatic cancer with limited therapeutic options. Consequently, most patients with advanced disease die from tumor progression. Current evidence indicates that a subset of cancer cells is responsible for tumor development, metastasis, and recurrence, and targeting these tumor-initiating cells is necessary to eradicate tumors. However, tumor-initiating cells and the biological processes that promote pathogenesis remain largely uncharacterized in PanNETs. Here we profile primary and metastatic tumors from an index patient and demonstrate that MET proto-oncogene activation is important for tumor growth in PanNET xenograft models. We identify a highly tumorigenic cell population within several independent surgically acquired PanNETs characterized by increased cell-surface protein CD90 expression and aldehyde dehydrogenase A1 (ALDHA1) activity, and provide in vitro and in vivo evidence for their stem-like properties. We performed proteomic profiling of 332 antigens in two cell lines and four primary tumors, and showed that CD47, a cell-surface protein that acts as a "don't eat me" signal co-opted by cancers to evade innate immune surveillance, is ubiquitously expressed. Moreover, CD47 coexpresses with MET and is enriched in CD90(hi)cells. Furthermore, blocking CD47 signaling promotes engulfment of tumor cells by macrophages in vitro and inhibits xenograft tumor growth, prevents metastases, and prolongs survival in vivo.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Escape del Tumor , Familia de Aldehído Deshidrogenasa 1 , Animales , Antígeno CD47/inmunología , Femenino , Humanos , Isoenzimas/inmunología , Masculino , Ratones Endogámicos NOD , Ratones SCID , Metástasis de la Neoplasia , Proteínas de Neoplasias/inmunología , Tumores Neuroendocrinos/inmunología , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/terapia , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Proto-Oncogenes Mas , Retinal-Deshidrogenasa/inmunología , Antígenos Thy-1/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Eur J Pharm Biopharm ; 101: 145-51, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26899127

RESUMEN

In this study, the influence of the molecular weight of polyvinylpyrrolidone (PVP) on the non-sink in vitro dissolution and in vivo performance of celecoxib (CCX):PVP amorphous solid dispersions were investigated. The dissolution rate of CCX from the amorphous solid dispersions increased with decreasing PVP molecular weight and crystallization inhibition was increased with increasing molecular weight of PVP, but reached a maximum for PVP K30. This suggested that the crystallization inhibition was not proportional with molecular weight of the polymer, but rather there was an optimal molecular weight where the crystallization inhibition was strongest. Consistent with the findings from the non-sink in vitro dissolution tests, the amorphous solid dispersions with the highest molecular weight PVPs (K30 and K60) resulted in significantly higher in vivo bioavailability (AUC0-24h) compared with pure amorphous and crystalline CCX. A linear relationship between the in vitro and in vivo parameter AUC0-24h indicated that the simple non-sink in vitro dissolution method used in this study could be used to predict the in vivo performance of amorphous solid dispersion with good precision, which enabled a ranking between the different formulations. In conclusion, the findings of this study demonstrated that the in vitro and in vivo performance of CCX:PVP amorphous solid dispersions were significantly controlled by the molecular weight of the polymer.


Asunto(s)
Celecoxib/química , Polímeros/química , Povidona/química , Animales , Disponibilidad Biológica , Celecoxib/farmacocinética , Química Farmacéutica/métodos , Cristalización , Masculino , Peso Molecular , Ratas , Ratas Sprague-Dawley , Solubilidad
19.
AAPS J ; 18(2): 416-23, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26769250

RESUMEN

Previous studies suggested that an amorphous solid dispersion with a copolymer consisting of both hydrophobic and hydrophilic monomers could improve the dissolution profile of a poorly water-soluble drug compared to the crystalline form. Therefore, this study investigated the influence of the copolymer composition of polyvinylpyrrolidone/vinyl acetate (PVP/VA) on the non-sink in vitro dissolution behavior and in vivo performance of celecoxib (CCX) amorphous solid dispersions. The study showed that the hydrophilic monomer vinylpyrrolidone (VP) was responsible for the generation of CCX supersaturation whereas the hydrophobic monomer vinyl acetate (VA) was responsible for the stabilization of the supersaturated solution. For CCX, there was an optimal copolymer composition around 50-60% VP content where further replacement of VP monomers with VA monomers did not have any biopharmaceutical advantages. A linear relationship was found between the in vitro AUC(0-4h) and in vivo AUC(0-24h) for the CCX:PVP/VA systems, indicating that the non-sink in vitro dissolution method applied in this study was useful in predicting the in vivo performance. These results indicated that when formulating a poorly water-soluble drug as an amorphous solid dispersion using a copolymer, the copolymer composition has a significant influence on the dissolution profile and in vivo performance. Thus, the dissolution profile of a drug can theoretically be tailored by changing the monomer ratio of a copolymer with respect to the required in vivo plasma-concentration profile. As this ratio is likely to be drug dependent, determining the optimal ratio between the hydrophilic (dissolution enhancing) and hydrophobic (crystallization inhibiting) monomers for a given drug is imperative.


Asunto(s)
Celecoxib/química , Polímeros/química , Povidona/química , Compuestos de Vinilo/química , Animales , Celecoxib/sangre , Química Farmacéutica , Masculino , Polímeros/metabolismo , Povidona/metabolismo , Ratas , Ratas Sprague-Dawley , Solubilidad , Compuestos de Vinilo/sangre , Difracción de Rayos X
20.
Anal Chem ; 87(13): 6667-73, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26035453

RESUMEN

Radiolabels can be used to detect small biomolecules with high sensitivity and specificity without interfering with the biochemical activity of the labeled molecule. For instance, the radiolabeled glucose analogue, [18F]fluorodeoxyglucose (FDG), is routinely used in positron emission tomography (PET) scans for cancer diagnosis, staging, and monitoring. However, despite their widespread usage, conventional radionuclide techniques are unable to measure the variability and modulation of FDG uptake in single cells. We present here a novel microfluidic technique, dubbed droplet radiofluidics, that can measure radiotracer uptake for single cells encapsulated into an array of microdroplets. The advantages of this approach are multiple. First, droplets can be quickly and easily positioned in a predetermined pattern for optimal imaging throughput. Second, droplet encapsulation reduces cell efflux as a confounding factor, because any effluxed radionuclide is trapped in the droplet. Last, multiplexed measurements can be performed using fluorescent labels. In this new approach, intracellular radiotracers are imaged on a conventional fluorescence microscope by capturing individual flashes of visible light that are produced as individual positrons, emitted during radioactive decay, traverse a scintillator plate placed below the cells. This method is used to measure the cell-to-cell heterogeneity in the uptake of tracers such as FDG in cell lines and cultured primary cells. The capacity of the platform to perform multiplexed measurements was demonstrated by measuring differential FDG uptake in single cells subjected to different incubation conditions and expressing different types of glucose transporters. This method opens many new avenues of research in basic cell biology and human disease by capturing the full range of stochastic variations in highly heterogeneous cell populations in a repeatable and high-throughput manner.


Asunto(s)
Fluorodesoxiglucosa F18/metabolismo , Análisis de la Célula Individual/métodos , Humanos
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