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1.
ACS Catal ; 14(15): 11584-11590, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39114090

RESUMEN

The ability to introduce noncanonical amino acids as axial ligands in heme enzymes has provided a powerful experimental tool for studying the structure and reactivity of their FeIV=O ("ferryl") intermediates. Here, we show that a similar approach can be used to perturb the conserved Fe coordination environment of 2-oxoglutarate (2OG) dependent oxygenases, a versatile class of enzymes that employ highly-reactive ferryl intermediates to mediate challenging C-H functionalizations. Replacement of one of the cis-disposed histidine ligands in the oxygenase VioC with a less electron donating N δ-methyl-histidine (MeHis) preserves both catalytic function and reaction selectivity. Significantly, the key ferryl intermediate responsible for C-H activation can be accumulated in both the wildtype and the modified protein. In contrast to heme enzymes, where metal-oxo reactivity is extremely sensitive to the nature of the proximal ligand, the rates of C-H activation and the observed large kinetic isotope effects are only minimally affected by axial ligand replacement in VioC. This study showcases a powerful tool for modulating the coordination sphere of nonheme iron enzymes that will enhance our understanding of the factors governing their divergent activities.

2.
Curr Opin Virol ; 67: 101424, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38981163

RESUMEN

Oncogenic viruses play a pivotal role in oncology due to their unique role in unraveling the complexities of cancer development. Understanding the role viruses play in specific cancers is important to provide basic insights into the transformation process, which will help identify potential cellular targets for treatment. This review discusses the diverse role of animal herpesviruses in initiating and promoting various forms of cancer. We will summarize the mechanisms that underlie the development of animal herpesvirus-induced cancer that may provide a basis for developing potential therapeutic interventions or preventative strategies in the future.


Asunto(s)
Infecciones por Herpesviridae , Herpesviridae , Neoplasias , Virus Oncogénicos , Animales , Herpesviridae/fisiología , Herpesviridae/patogenicidad , Herpesviridae/genética , Humanos , Neoplasias/virología , Infecciones por Herpesviridae/virología , Virus Oncogénicos/fisiología , Carcinogénesis
4.
Otolaryngol Head Neck Surg ; 169(6): 1533-1541, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37418217

RESUMEN

OBJECTIVE: To define novel gene biomarkers for prognosis of head and neck squamous cell carcinoma (HNSCC) patients' survival. STUDY DESIGN: Retrospective study. SETTING: The Cancer Genome Atlas (TCGA) HNSCC RNA-Seq dataset. METHODS: Coexpressed gene clusters were extracted from TCGA RNA-seq data using our previously published method (EPIG). Kaplan-Meier estimator was then used for overall survival-relevant analysis, with patients partitioned into 3 groups based on gene expression levels: female, male_low, and male_high. RESULTS: Male had better overall survival than female and male with higher expression level of Y-chromosome-linked (Y-linked) genes had significantly better survival than those with lower expression levels. In addition, male with a higher expression level of Y-linked genes showed even better survival when they have a higher level of coexpressed cluster of genes related to B or T cell immune response. Other clinical conditions related to immune responses also consistently showed favorable effects on the Y-linked genes for survival estimation. Male patients with higher expression level of Y-linked genes also have significantly higher tumor/normal tissue (T/N) ratio of those genes and higher level of several immune responses related clinical measurements (eg, lymphocyte and TCR related). Male patients with lower expression level of Y-linked genes benefited from radiation-only treatment. CONCLUSIONS: The favorable role of a cluster of coexpressed Y-linked genes in HNSCC patients' survival is potentially associated with elevated level of immune responses. These Y-linked genes could serve as useful prognostic biomarkers for HNSCC patients' survival estimation and treatment.


Asunto(s)
Neoplasias de Cabeza y Cuello , Humanos , Masculino , Femenino , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/genética , Genes Ligados a Y , Estudios Retrospectivos , Pronóstico , Cromosomas , Biomarcadores , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica
5.
Cureus ; 15(5): e39236, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37337483

RESUMEN

The use of synthetic cannabinoids and marijuana has been known to be associated with myocardial infarction and coronary vasospasms according to a few case reports published for the pediatric population. The data on the use of synthetic cannabinoids and myocardial infarction in adults however is limited. The adverse effects of these so-called designer drugs have been far-reaching. Here, we describe a case of an adult male with ST-elevated myocardial infarction diagnosed secondary to smoking synthetic cannabinoids.

6.
Head Neck ; 44(11): 2571-2578, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36047613

RESUMEN

BACKGROUND: To describe intensity-modulated radiotherapy (IMRT) with Gamma Knife Radiosurgery (GKRS) boost for locally advanced head and neck cancer (HNC) with disease near dose-limiting structures. METHODS: Patients with HNC treated with IMRT/GKRS as part of a combined modality approach between 2011 and 2021 were reviewed. Local control, overall survival and disease-specific survival were estimated using the Kaplan Meier method. RESULTS: Twenty patients were included. Nineteen patients had T3-4 tumors. Median follow-up was 26.3 months. GKRS site control was 95%. Two patients progressed at the treated primary site, one patient failed at the edge of the GKRS treatment volume, with no perineural or intracranial failure. 2-year OS was 94.7% (95% CI: 85.2%-100%). Concurrent chemotherapy was given in nine patients (45%). One patient (5%) received induction/concurrent chemotherapy. Brain radionecrosis occurred in three patients, one of which was biopsy-proven. CONCLUSIONS: IMRT plus GKRS boost results in excellent disease control near critical structures with minimal toxicity.


Asunto(s)
Neoplasias de Cabeza y Cuello , Radiocirugia , Radioterapia de Intensidad Modulada , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Radiocirugia/efectos adversos , Radiocirugia/métodos , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos , Resultado del Tratamiento
7.
Front Oncol ; 12: 939118, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36110959

RESUMEN

Translational Relevance: Evaluation of targeted therapies is urgently needed for the majority of patients with metastatic/recurrent head and neck squamous cell carcinoma (HNSCC) who progress after immunochemotherapy. Erlotinib, a targeted inhibitor of epidermal growth factor receptor pathway, lacks FDA approval in HNSCC due to inadequate tumor response. This study identifies two potential avenues to improve tumor response to erlotinib among patients with HNSCC. For the first time, this study shows that an increased erlotinib dose of 300 mg in smokers is well-tolerated and produces similar plasma drug concentration as the regular dose of 150 mg in non-smokers, with increased study-specific defined tumor response. The study also highlights the opportunity for improved patient selection for erlotinib treatment by demonstrating that early in-treatment [18]FDG PET/CT is a potential predictor of tumor response, with robust statistical correlations between metabolic changes on early in-treatment PET (4-7 days through treatment) and anatomic response measured by end-of-treatment CT. Purpose: Patients with advanced HNSCC failing immunochemotherapy have no standard treatment options. Accelerating the investigation of targeted drug therapies is imperative. Treatment with erlotinib produced low response rates in HNSCC. This study investigates the possibility of improved treatment response through patient smoking status-based erlotinib dose optimization, and through early in-treatment [18]FDG PET evaluation to differentiate responders from non-responders. Experimental design: In this window-of-opportunity study, patients with operable HNSCC received neoadjuvant erlotinib with dose determined by smoking status: 150 mg (E150) for non-smokers and 300 mg (E300) for active smokers. Plasma erlotinib levels were measured using mass spectrometry. Patients underwent PET/CT before treatment, between days 4-7 of treatment, and before surgery (post-treatment). Response was measured by diagnostic CT and was defined as decrease in maximum tumor diameter by ≥ 20% (responders), 10-19% (minimum-responders), and < 10% (non-responders). Results: Nineteen patients completed treatment, ten of whom were smokers. There were eleven responders, five minimum-responders, and three non-responders. Tumor response and plasma erlotinib levels were similar between the E150 and E300 patient groups. The percentage change on early PET/CT and post-treatment PET/CT compared to pre-treatment PET/CT were significantly correlated with the radiologic response on post-treatment CTs: R=0.63, p=0.0041 and R=0.71, p=0.00094, respectively. Conclusion: This pilot study suggests that early in-treatment PET/CT can predict response to erlotinib, and treatment with erlotinib dose adjusted according to smoking status is well-tolerated and may improve treatment response in HNSCC. These findings could help optimize erlotinib treatment in HNSCC and should be further investigated. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT00601913, identifier NCT00601913.

8.
Laryngoscope ; 132(9): 1792-1797, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35043989

RESUMEN

OBJECTIVES: Neck Imaging Reporting and Data System (NI-RADS) is a radiology reporting system for head and neck cancer surveillance. Imaging findings of high suspicion for recurrence are assigned Category 3 and recommended for "Biopsy, if clinically indicated." After implementing NI-RADS for surveillance neck computed tomography (CT), our objectives are to determine the incidence of squamous cell carcinoma (SCC) Category 3 lesions in the year post-implementation, the associated biopsy rate, and the positive predictive value of NI-RADS 3 for SCC recurrence. STUDY DESIGN: Retrospective cohort study. METHODS: Neck CTs reported with NI-RADS between February 2020 and February 2021 were reviewed to identify patients undergoing surveillance for SCC assigned NI-RADS 3. Cancer recurrence, defined as positive biopsy result or treatment of clinically determined recurrence, was determined by electronic medical record review. RESULTS: During the study period, 580 neck CTs were reported with NI-RADS, of which 39 (7%) CTs obtained in 37 unique patients (28 male, 9 female, mean age 66.6 years) formed the study cohort. Biopsies were obtained in 23 lesions (45%), of which 17 (74%) were positive for recurrent SCC. One nondiagnostic biopsy was clinically determined to represent recurrence. Of 28 (55%) lesions not biopsied, 18 (64%) were ultimately treated as clinically determined recurrence. Thus, among 51 individual NI-RADS 3 lesions (32 primary, 19 neck), 36 (71%) represented recurrence. CONCLUSION: The incidence of NI-RADS 3 lesions in our cohort was 7%. The biopsy rate was 45%, and the overall positive predictive value of NI-RADS 3 for recurrent SCC was 71%. Category 3 lesions are associated with substantial SCC recurrence risk and should be managed accordingly. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:1792-1797, 2022.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Anciano , Biopsia , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/epidemiología , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/epidemiología , Humanos , Incidencia , Masculino , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Carcinoma de Células Escamosas de Cabeza y Cuello/epidemiología , Tomografía Computarizada por Rayos X/métodos
9.
Chemistry ; 28(7): e202103982, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34911156

RESUMEN

Aryloxyalkanoate dioxygenases are unique herbicide biodegrading nonheme iron enzymes found in plants and hence, from environmental and agricultural point of view they are important and valuable. However, they often are substrate specific and little is known on the details of the mechanism and the substrate scope. To this end, we created enzyme models and calculate the mechanism for 2,4-dichlorophenoxyacetic acid biodegradation and 2-methyl substituted analogues by density functional theory. The work shows that the substrate binding is tight and positions the aliphatic group close to the metal center to enable a chemoselective reaction mechanism to form the C2 -hydroxy products, whereas the aromatic hydroxylation barriers are well higher in energy. Subsequently, we investigated the metabolism of R- and S-methyl substituted inhibitors and show that these do not react as efficiently as 2,4-dichlorophenoxyacetic acid substrate due to stereochemical clashes in the active site and particularly for the R-isomer give high rebound barriers.


Asunto(s)
Dioxigenasas , Herbicidas , Biodegradación Ambiental , Dominio Catalítico , Dioxigenasas/metabolismo , Hierro , Especificidad por Sustrato
10.
Laryngoscope ; 132(2): 349-355, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34272871

RESUMEN

OBJECTIVES/HYPOTHESIS: Neck Imaging Reporting and Data System (NI-RADS) is a radiology reporting system developed for head and neck cancer surveillance imaging, using standardized terminology, numeric levels of suspicion, and linked management recommendations. Through a multidisciplinary, interdepartmental quality improvement initiative, we implemented NI-RADS for the reporting of head and neck cancer surveillance CT. Our objective is to summarize our initial experience from the standpoints of head and neck cancer providers and radiologists. STUDY DESIGN: Quality improvement study. METHODS: Before and 3 months post-implementation, surveys were offered to referring physicians (n = 21 pre-adoption; 22 post-adoption) and radiologists (n = 17 pre- and post-adoption). NI-RADS utilization was assessed over time. RESULTS: Survey response rates were 62% (13/21) and 73% (16/22) for referring physicians pre- and post-adoption, respectively, and 94% (16/17) for radiologists pre- and post-adoption. Among post-adoption provider respondents, 100% (16/16) strongly agreed or agreed with "I want our radiologists to continue using NI-RADS," "The NI-RADS numerical rating of radiologic suspicion is helpful," and "The language and style of NI-RADS neck CT reports are clear and understandable." Among radiologist respondents, 88% (14/16) strongly agreed or agreed with "NI-RADS improves consistency among our radiologists in the reporting of surveillance neck CTs." Radiologist NI-RADS utilization increased over time (46% month 1; 72% month 3). CONCLUSIONS: Most referring physicians and radiologists preferred NI-RADS. Head and neck cancer providers indicated that NI-RADS reports are clear, understandable, direct, and helpful in guiding clinical management. Radiologists indicated that NI-RADS improves radiologist consistency in the reporting of surveillance neck CT, and radiologists increasingly used NI-RADS over time. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:349-355, 2022.


Asunto(s)
Competencia Clínica , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Cuello/diagnóstico por imagen , Neurología , Oncología por Radiación , Radiología , Proyectos de Investigación , Tomografía Computarizada por Rayos X , Humanos , Derivación y Consulta
11.
Top Magn Reson Imaging ; 30(2): 117-130, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33828063

RESUMEN

ABSTRACT: Transoral robotic surgery (TORS) is an excellent treatment strategy for well-selected patients with oropharyngeal squamous cell carcinoma. Potential benefits of TORS are greatest among patients for whom surgical resection will reduce or eliminate the need for adjuvant therapy. Proper patient selection largely depends on imaging, which is used to determine tumor resectability, to inform expected morbidity and functional outcome, to assess the potential need for adjuvant therapy, to evaluate for vascular or other anatomic contraindications, and to gauge adequacy of transoral access to the tumor. This article provides the radiologist with a practical and accessible approach to interpreting preoperative imaging among patients with oropharyngeal cancer, emphasizing what the surgeon wants to know to inform the determination of whether the patient is a TORS candidate and why this information is important. By accurately reporting this information, the radiologist facilitates the multidisciplinary care team's selection of a treatment regimen optimized for the circumstances of the individual patient.


Asunto(s)
Neoplasias Orofaríngeas/cirugía , Selección de Paciente , Procedimientos Quirúrgicos Robotizados , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía , Cirujanos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Resultado del Tratamiento
12.
J Org Chem ; 85(19): 12682-12691, 2020 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-32865412

RESUMEN

A density functional theory study is presented here to offer mechanistic insights and explications of experimentally intriguing observations in the Au(I)-catalyzed cyclization of cyclic and acyclic acetals of alkynylaldehydes that leads to indenone formation. The reactivity of catalytic cycles with and without methoxy migration is clearly defined when the alkyne terminus is phenylated. The reaction mechanism of indenone formation proceeds first with the coordination of Au(I) to alkyne to initiate the reaction with 1,5-H shift as a rate-determining step (RDS), and the fastest 1,5-H shift is achieved when one phenyl ring carries an electron-donating group and the other one is substituted with an electron-withdrawing group. Following the 1,5-H shift, the reaction undergoes feasible steps that are cyclization and 1,2-H shift before elimination to persist the iterative cycle, but the reactivity of both steps is highly affected by the existence of the phenyl group on the alkyne terminus. The unreactivity of the alkyne terminus not bearing a phenyl ring is because the cyclization is thermodynamically disfavorable, subsequently deactivating the 1,2-H shift kinetically and thermodynamically. The absence of a tether in the acetal unit considerably outpaces any 1,5-H shift and instead activates 1,5-methoxy migration, giving methoxy-migrated indenone, with the 1,2-OMe shift being an RDS.

13.
Am J Otolaryngol ; 41(4): 102477, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32307191

RESUMEN

Postoperative hypocalcemia is a well-described outcome following thyroid and parathyroid surgery with symptoms ranging from clinically insignificant laboratory findings to tetany and seizures. The aims of this study were 1. To identify the characteristics and management patterns of postoperative hypocalcemia in head and neck endocrine surgery patients and 2. To compare outcomes between patients treated with empiric calcium and patients treated using a biochemically driven calcium replacement algorithm. Clinical electronic medical record (EMR) data was collected from patients who had undergone total thyroidectomy, completion thyroidectomy, and/or parathyroidectomy at Wake Forest Baptist Medical Center (WFBMC), a tertiary referral and academic institution. Between July 1, 2016, and June 30, 2017, 298 adult patients underwent surgery by a WFBMC Head & Neck (H&N) endocrine surgeon. Objective calcium and parathyroid hormone levels, postoperative supplementation with calcium and Vitamin D, 30-day physician access line (PAL) phone call utilization, emergency department (ED) encounters, and readmission rates were queried. The overall rate of hypocalcemia was 17.4%. No statistically significant difference in PAL utilization, ED visits, or readmissions was found between the empiric supplementation group and those whose supplementation was biochemically directed (PAL 5.0% vs. 5.0% [p = 0.983], ED visit 3.3% vs. 2.5% [p = 0.744], Readmission 1.7% vs. 0% [p = 0.276]). The overall postoperative rates of hypocalcemia and hypoparathyroidism following H&N endocrine surgery were consistent with the reported literature. Neither method of calcium supplementation was superior in reducing PAL utilization, ED encounters, or readmission.


Asunto(s)
Calcio/administración & dosificación , Hipocalcemia/tratamiento farmacológico , Paratiroidectomía , Complicaciones Posoperatorias/tratamiento farmacológico , Tiroidectomía , Adulto , Anciano , Femenino , Humanos , Hipocalcemia/epidemiología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Pronóstico , Estudios Retrospectivos , Vitamina D/administración & dosificación
14.
Arch Insect Biochem Physiol ; 103(4): e21643, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31667894

RESUMEN

Mass spectrometry imaging (MSI) can visualize the composition, abundance, and spatial distribution of molecules in tissues or cells, which has been widely used in the research of life science. Insects, especially the agricultural pests, have received a great deal of interests from the scientists in biodiversity and food security. This review introduces the major characteristics of MSI, summarizes its application to the investigation of insect endogenous metabolites, exogenous metabolites, and the spatiotemporal changes of metabolites between insects and plants, and discusses its shortfalls and perspectives. The significance of these concerns is beneficial for future insect research such as physiology and metabolism.


Asunto(s)
Insectos/metabolismo , Espectrometría de Masas/métodos , Plantas/química , Animales
15.
Radiol Case Rep ; 14(9): 1103-1108, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31338135

RESUMEN

We present a case of a 63-year-old male with an 8-year history of a left-sided cystic facial mass which recurred despite multiple drainage procedures. Imaging findings showed a cystic mass in the left parotid gland and it was surgically resected. Pathology confirmed it to represent a mammary analogue secretory carcinoma, a relatively newly described entity. This case illustrates that mammary analogue secretory carcinoma can masquerade as a cyst within the parotid gland.

16.
Cureus ; 11(12): e6512, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-32025431

RESUMEN

Hypothesis Beta-blockers (BBs) lower the heart rate, which may mask the diagnosis of pulmonary embolism (PE) since one of the main clinical diagnoses of PE is tachycardia. The endpoint of our retrospective study is to determine if the pre-existing use of (BB) significantly affects the utility of these scoring criteria in diagnosing PE. Introduction Diagnosing PE is a challenge because of the non-specificity of its symptoms and signs. The initial step is to assess the patient's likelihood of having a PE. This involves using a scoring system to stratify patients into different levels of risk of having PE (for example, as 'low,' 'moderate,' or 'high' risk). Some of the commonly used criteria are Wells' Score, Geneva Score, and Pulmonary Embolism Rule-out Criteria (PERC) Rule (Charlotte Rule). Methodology This retrospective study was conducted at St. Francis Medical Center. Subjects were taken from a patient population with a new diagnosis of PE (between 2010 and 2017) on the basis of computed tomography angiography (CTA) of the chest. Patients with sepsis or septic shock, heart block, atrioventricular (AV) nodal ablation, pacemaker placement, or taking more than one AV nodal blocker were excluded from the study. Subjects were categorized on the basis of beta-blocker consumption. Result Out of a total of 170 cases, 71 patients were taking beta-blockers and 99 patients were not taking beta-blockers. Among the participants taking BBs, 30.4% had a heart rate <60 and 55.8% had a heart rate between 60 and 100. Conclusion BBs significantly obviate tachycardia in patients with PE. It falsely decreases the Wells' Score and the Geneva Score and results in the inappropriate fulfilling of PERC criteria.

17.
Sci Rep ; 8(1): 10830, 2018 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-29997395

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

18.
Laryngoscope ; 128(10): 2273-2281, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29729008

RESUMEN

OBJECTIVES/HYPOTHESIS: To demonstrate anatomic relationships of the far-medial transoral endoscopic assisted approach (FMT-EAA) to the infratemporal fossa (ITF) and define the corridor dimensions, surgical freedom, and limitations associated with this approach. STUDY DESIGN: Cadaveric study. METHODS: Twenty ITFs (10 specimens) were dissected with the assistance of 0 °, 30 °, and 45 ° rod-lens endoscopes. Image guidance was used to confirm and measure the corridors' structural boundaries and document the anatomical relationships encountered in this approach. RESULTS: Access to the ITF via the FMT-EAA can be divided into two secondary surgical corridors: the superomedial and inferolateral triangles, each of which provides access to different areas. The superomedial triangle is bounded medially by the lateral pterygoid plate and posterolateral maxillary sinus wall, superiorly by the greater sphenoid wing, and inferolaterally by the lateral pterygoid muscle. The inferolateral triangle is bounded superiorly by the lower head of the lateral pterygoid muscle, inferiorly by the medial pterygoid muscle, and laterally by the mandible. Using a standard 19-mm endoscope, the FMT-EAA achieves a mean surgical freedom of 231 mm and 161 mm in the vertical and horizontal planes, respectively. CONCLUSIONS: FMT-EAA adequately exposes critical structures of the ITF. This technique is a viable option for the management of selected ITF lesions, either alone or in combination with alternative minimally invasive approaches to the region. LEVEL OF EVIDENCE: NA Laryngoscope, 128:2273-2281, 2018.


Asunto(s)
Fosa Craneal Posterior/cirugía , Cirugía Endoscópica por Orificios Naturales/métodos , Hueso Temporal/cirugía , Cadáver , Fosa Craneal Posterior/anatomía & histología , Humanos , Tomografía Computarizada por Rayos X/métodos
19.
Sci Rep ; 8(1): 3093, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29449631

RESUMEN

The energy density of conventional supercapacitors is in the range of 6-10 Wh kg-1, which has restricted them from many applications that require devices with long durations. Herein, we report a method for enhancing the energy density of a device through the parallel stacking of five copper foils coated on each side with graphene nanoplatelets. Microporous papers immersed in 2 M aqueous sodium sulphate were used as separators. With a low contact resistance of 0.05 Ω, the supercapacitor yielded an optimum specific energy density and a specific power density of 24.64 Wh kg-1 and 402 W kg-1 at 0.8 V, respectively. The working potential was increased to 2.4 V when three of the supercapacitors were connected in series, forming a tandem device. Its potential for real applications was manifested by the ability to light up a light-emitting diode for 40 s after charging for 60 s.

20.
Nanomedicine (Lond) ; 13(1): 25-41, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29173059

RESUMEN

AIM: Our aim was to inhibit trypanothione reductase (TR) and P-gp efflux pump of Leishmania by the use of thiolated polymers. Thus, increasing the intracellular accumulation and therapeutic effectiveness of antimonial compounds. METHODS: Mannosylated thiolated chitosan and mannosylated thiolated chitosan-polyethyleneimine graft were synthesized and characterized. Meglumine antimoniate-loaded nanoparticles were prepared and evaluated for TR and P-gp efflux pump inhibition, biocompatibility, macrophage uptake and antileishmanial potential. RESULTS: Thiomers inhibited TR with Ki 2.021. The macrophage uptake was 33.7- and 18.9-fold higher with mannosylated thiolated chitosan-polyethyleneimine graft and mannosylated thiolated chitosan nanoparticles, respectively, as compared with the glucantime. Moreover, the in vitro antileishmanial activity showed 14.41- and 7.4-fold improved IC50 for M-TCS-g-PEI and M-TCS, respectively as compared with glucantime. CONCLUSION: These results encouraged the concept that TR and P-gp inhibition by the use of thiomers improves the therapeutic efficacy of antimonial drugs.


Asunto(s)
Antiprotozoarios/farmacología , Quitosano/análogos & derivados , Portadores de Fármacos/química , Leishmaniasis/tratamiento farmacológico , Meglumina/farmacología , Nanopartículas/química , Compuestos Organometálicos/farmacología , Polietileneimina/análogos & derivados , Antiprotozoarios/química , Transporte Biológico , Quitosano/síntesis química , Liberación de Fármacos , Humanos , Leishmania/efectos de los fármacos , Manosa/química , Meglumina/química , Antimoniato de Meglumina , Compuestos Organometálicos/química , Tamaño de la Partícula , Polietileneimina/síntesis química , Compuestos de Sulfhidrilo/química , Propiedades de Superficie
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