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1.
J Vasc Surg ; 70(2): 629-640.e1, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30922754

RESUMO

BACKGROUND: Patients undergoing vascular operations face high rates of intraoperative and postoperative complications and delayed return to baseline. Enhanced recovery after surgery (ERAS), with its aim of delivering high-quality perioperative care and accelerating recovery, appears well suited to address the needs of this population. METHODS: In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we performed a systematic review to characterize the use and effectiveness of ERAS in all types of vascular and endovascular operations. We queried MEDLINE (through PubMed), Embase, Web of Science, Scopus, ProQuest Dissertations and Theses Global, Cochrane Central Register of Controlled Trials, Prospero, and Google Scholar. Two reviewers independently completed screening, review, and quality assessment. Eligible articles described the use of ERAS pathways for vascular operations from January 1, 1997, through December 7, 2017. Details regarding patients' demographics and use of the ERAS pathway or selected ERAS components were extracted. When available, results including perioperative morbidity, mortality, and in-hospital length of stay were collected. The studies with control groups that evaluated ERAS-like pathways were meta-analyzed using random-effects meta-analysis. RESULTS: In the final analysis, 19 studies were included: four randomized controlled trials and 15 observational studies. By Let Evidence Guide Every New Decision (LEGEND) criteria, the two good-quality studies are randomized controlled trials that evaluated a specific part of an ERAS pathway. All other studies were considered poor quality. Meta-analysis of the five studies describing ERAS-like pathways demonstrated a reduction in length of stay by 3.5 days (P = .0012). CONCLUSIONS: Based on systematic review, the use of ERAS pathways in vascular surgery is limited, and existing evidence of their feasibility and effectiveness is low quality. There is minimal poor- to moderate-quality evidence describing the use of ERAS pathways in open aortic operations. There is scarce, poor-quality evidence related to ERAS pathways in lower extremity operations and no published evidence related to ERAS pathways in endovascular operations. Although the risk of bias is high in most of the studies done to date, all of them observed improvements in length of stay, postoperative diet, and ambulation. It is reasonable to consider the implementation of ERAS pathways in the care of vascular surgery patients, specifically those undergoing open aortic operations, but many of the details will be based on limited data and extrapolation from other surgical specialties until further research is done.


Assuntos
Protocolos Clínicos , Recuperação Pós-Cirúrgica Melhorada , Tempo de Internação , Complicações Pós-Operatórias/prevenção & controle , Procedimentos Cirúrgicos Vasculares , Humanos , Alta do Paciente , Recuperação de Função Fisiológica , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos
2.
Psychosomatics ; 60(3): 227-237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30733043

RESUMO

BACKGROUND: Patients with cancer frequently experience neuropsychiatric symptoms due to their medical illness or its treatment. In recent decades, psychiatrists have become increasingly involved in the care of patients with cancer. However, psychiatrists may be less familiar with hematopoietic stem cell transplantation (HSCT), a distinct cancer treatment modality associated with multiple neuropsychiatric sequelae. OBJECTIVE: To provide an overview of HSCT, and describe the prevalence, impact, risk factors, and suggested management of psychiatric consequences of HSCT. METHODS: We performed literature searches in PubMed and PsychInfo to identify articles describing neuropsychiatric symptoms, including depression, anxiety, distress, post-traumatic stress disorder, delirium and cognitive impairment, resulting from HSCT in adults. Those articles most relevant to this manuscript were included. RESULTS: Psychiatrists may be involved in the treatment of patients before, during, or after inpatient hospitalization for HSCT. Each phase of treatment introduces unique stressors that may lead to or exacerbate psychiatric disorders. Appropriate management requires evaluation of HSCT-related medications, an understanding of the impact of complications from HSCT, and consideration of how the patient's underlying medical condition should influence psychiatric recommendations. CONCLUSION: To optimize patient outcomes, consulting psychiatrists should be familiar with the basic principles of HSCT, and the neuropsychiatric sequelae that may result from treatment. Further research is needed to identify strategies to manage psychiatric complications in this unique population.


Assuntos
Transplante de Células-Tronco Hematopoéticas/psicologia , Transtornos Mentais/etiologia , Ansiedade/etiologia , Ansiedade/terapia , Depressão/etiologia , Depressão/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Transtornos Mentais/terapia , Estresse Psicológico/etiologia , Estresse Psicológico/terapia
3.
Psychosomatics ; 60(2): 139-152, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30665668

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is an increasingly common cause of behavioral and emotional dysregulation among hospitalized patients. While consultation-liaison psychiatrists are often called to help manage these behaviors, acute pharmacological management guidelines are limited. OBJECTIVE: Conduct a systematic review to determine which pharmacological measures are supported by the literature for targeting agitation and aggression in the acute time period following a TBI. METHODS: In a systematic review of MEDLINE, Embase, PsycInfo, ClinicalTrials.gov and the Cochrane Library, we identified and then analyzed publications that investigated the pharmacological management of behavioral and emotional dysregulation following a TBI during the acute time period following injury. RESULTS: There were a limited number of high quality studies that met our inclusion criteria, including only five randomized controlled trials. The majority of the literature identified consisted of case reports or case series. Trends identified in the literature reviewed suggested that amantadine, propranolol, and anti-epileptics were the best supported medications to consider. For many medication classes, the time of medication initiation and duration of treatment, relative to the time of injury, may impact the effect observed. CONCLUSIONS: The pharmacological management of agitated patients immediately following a TBI is still an area of much-needed research, as there is limited data-driven guidance in the literature.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Agressão/psicologia , Amantadina/uso terapêutico , Anticonvulsivantes/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Dopaminérgicos/uso terapêutico , Regulação Emocional , Comportamento Problema/psicologia , Propranolol/uso terapêutico , Doença Aguda , Lesões Encefálicas Traumáticas/psicologia , Humanos , Guias de Prática Clínica como Assunto
4.
J Med Libr Assoc ; 107(3): 403-410, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31258446

RESUMO

BACKGROUND: The following case example provides an overview of one innovative way to engage health professions faculty with health sciences librarians in the development of an interprofessional book discussion and identifies strategies to address implementation challenges. Academic health sciences librarians worked with the Interprofessional Education (IPE) Steering Committee to organize interprofessional book discussion groups for incoming health professions students. This inaugural book discussion brought together students and faculty of different disciplines to engage students in "learning from, with, and about" other professions. CASE PRESENTATION: When Breath Becomes Air, by Paul Kalanithi, allowed involved discussions on important health sciences issues. The project included outreach, designing pre- and post-surveys, scheduling participants, and communicating with all participants before, during, and after the event. A total of seventy-nine students and thirty-six faculty, representing all health professions schools, participated in the small group IPE book discussions over two weeks. CONCLUSIONS: Small group book discussions have been shown to be an effective tool to engage students and faculty in IPE. The results of the participant surveys were positive, and the IPE Steering Committee found value in including health sciences librarians throughout the process. Lessons learned from the pilot project include needing an efficient scheduling system, strongly communicating at all stages of the project, and starting the planning process months ahead of time. The IPE Steering Committee plans to conduct similar book discussions every fall semester moving forward and explore options for other IPE events.


Assuntos
Livros , Comportamento Cooperativo , Educação Médica/organização & administração , Docentes de Medicina/psicologia , Ocupações em Saúde/educação , Relações Interprofissionais , Bibliotecários/psicologia , Adulto , Currículo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
5.
Pancreatology ; 18(7): 700-704, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30139657

RESUMO

BACKGROUND: Patients with cystic fibrosis (CF) and a CFTR gene mutation may present with a variety of pancreatic disorders. The presence of multiple macrocysts (>1 cm) replacing the entire pancreatic parenchyma is termed pancreatic cystosis. Lack of clear data makes clinical decision making challenging and controversial. The aim of this review is to perform a qualitative systematic analysis of the literature with intention to evaluate management plans. METHODS: Electronic databases MEDLINE, Embase, and Scopus were searched for relevant studies, and 19 studies describing patients with pancreatic cystosis were included and analyzed for clinical features and therapy offered. RESULTS: The data of 24 patients were collected from included studies. Eight cases (33%) had a documented CFTR gene mutation and 10 (42%) were symptomatic at presentation. Imaging modalities included ultrasound in 18 (75%), CT in 12 (50%), and MRI in 8 (33%) cases. An average size of the largest cyst was 5.4 cm. 6 (25%) patients were offered therapy that described surgical (3), endoscopic (1), or medical therapy (2). Surgeries offered included total pancreatectomy, partial pancreatic resection of uncertain extent, and complex cyst resection. Endoscopic treatment was cystogastrostomy. Novel medical treatment was utilized with Doxepin, Propantheline, and Clonidine, resulting in reduction in cyst size and overall clinical improvement. CONCLUSION: Patients with pancreatic cystosis should not be denied treatment when necessary. This literature review is the most comprehensive thus far of cystic fibrosis and pancreatic cystosis, and it did not provide identification of a definitive treatment plan or demonstrate contraindication to specific therapies.


Assuntos
Fibrose Cística/complicações , Cisto Pancreático/etiologia , Cisto Pancreático/terapia , Predisposição Genética para Doença , Humanos , Cisto Pancreático/patologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-29775400

RESUMO

Tin dioxide nanofibers (SnDNFs) are small fibers that have many applications. Tin dioxide nanofibers can be used in cosmetics, solar cells, toxic gas release sensors, and air pollution control. To date there have been few studies on the cytotoxicity of SnDNFs. The goal of this research is to determine if electrospun SnDNFs are toxic in a lung cancer cell line (A549). Considering the nano-scale size of the fibers, they can easily be inhaled and enter the pulmonary system and cause toxic effects in the lung. Occupational exposure to SnDNFs has been linked to pulmonary disease, making the A549 cell line important in this study. Nanofiber toxicity can vary based upon the characteristics of the fibers. Smaller nanofibers have been shown to have more toxic effects than their larger counterparts. The synthesized SnDNFs were characterized using SEM, Raman spectroscopy, and powder X-ray diffractometer (PXRD). SEM images showed the fibers to be 200-300 nm in diameter. Raman spectroscopy and PXRD indicated that the fibers were in the rutile phase. After quantifying the SnDNFs, the fibers were introduced to A549 cells at concentrations ranging from 0.02-500 µg mL-1 and incubated at 37°C. These cells were quantified with the MTT assay to measure cell proliferation (IC50 = 0.02 mg mL-1), while lactate dehydrogenase (LDH) leakage was used to determine cytotoxicity, and apoptosis assays to assess the mechanism of cell death. Increasing concentration of SnDNF generated a consequential decrease in cell proliferation and viability. The percent cytotoxicity of SnDNF was not significantly changed at the various concentrations and time frames. In order to gain additional insight about the mechanism of cytotoxicity of SnDNFs, genes with links to inflammation and apoptosis were evaluated and found to be over-expressed in treated cells. At the concentrations of SnDNF examined, SnDNF was mildly toxic to the A549 cells.


Assuntos
Apoptose/efeitos dos fármacos , Nanofibras/toxicidade , Compostos de Estanho/toxicidade , Células A549 , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Humanos , Teste de Materiais , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Testes de Toxicidade
7.
N C Med J ; 79(4): 245-249, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29991618

RESUMO

Interdisciplinary health care teams have numerous opportunities to investigate more efficient health care delivery mechanisms using technology that bridges information science and human-centered care. At the onset of team formation, technology can be strategically integrated to enhance health care delivery for patients and providers using multiple strategies.


Assuntos
Acessibilidade aos Serviços de Saúde , Equipe de Assistência ao Paciente , Telemedicina , Humanos , North Carolina , Estados Unidos
8.
Angew Chem Int Ed Engl ; 55(41): 12626-31, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27377046

RESUMO

Water-soluble platinum(IV) prodrugs, which proved kinetically stable to reduction in the presence of physiological concentration of ascorbate, were quickly reduced to their active form, oxaliplatin, when co-incubated with a macrocycle metallotexaphyrin (i.e., Motexafin Gadolinium (MGd)). The reduction of Pt(IV) to Pt(II) promoted by MGd occurs in cell culture as well, leading to an increase in the antiproliferative activity of the Pt(IV) species in question. The mediated effect is proportional to the concentration of MGd and gives rise to an enhancement when the prodrug is relatively hydrophilic. MGd is known to localize/accumulate preferentially in tumor tissues. Thus, the present "activation by reduction" approach may allow for the cancer-selective enhancement in the cytotoxicity of Pt(IV) prodrugs.


Assuntos
Antineoplásicos/química , Metaloporfirinas/química , Platina/química , Pró-Fármacos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas Eletroquímicas , Humanos , Oxirredução , Platina/farmacologia , Pró-Fármacos/farmacologia
9.
Acad Med ; 97(3): 444-458, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34907962

RESUMO

PURPOSE: Research has shown that barriers to career success in academic medicine disproportionately affect women. These barriers include inadequate mentoring, which may perpetuate the underrepresentation of women in senior leadership positions. The purpose of this review was to summarize the qualitative and quantitative evidence of the impact of mentoring on women's career outcomes and to inform future interventions to support the promotion and retention of women in academic medicine. METHOD: The authors conducted a systematic review of original research published in English-language, peer-reviewed journals through March 20, 2020. Search terms related to mentorship, women, and academic medicine. The authors searched MEDLINE, Embase, Scopus, Current Contents Connect via Web of Science, Cochrane Library, and PsycINFO. They excluded studies not specifically addressing women and those without gender-stratified outcomes. They extracted and analyzed the following data: study design, population, sample size, response rate, participant age, percentage of women, mentoring prevalence, and outcomes. RESULTS: Of 2,439 citations identified, 91 studies met the inclusion criteria, including 65 quantitative and 26 qualitative studies. Mentoring was associated with objective and subjective measures of career success. Women perceived mentorship to be more valuable to their career development yet were more likely to report having no mentor. Additionally, women were more likely to report lower levels of research productivity, less career satisfaction, and greater barriers to promotion. Qualitative results indicated that women had less access to informal mentoring and family responsibilities had a greater effect on their career outcomes. Professional networking, female mentors, and relational aspects of mentoring were common themes. CONCLUSIONS: This review examined gender disparities in mentoring and the impact on research productivity, promotion success, and career satisfaction for women in academic medicine. Institution-supported mentoring programs are needed to facilitate identification of appropriate mentors and promotion of a more equitable academic career environment for women.


Assuntos
Sucesso Acadêmico , Medicina , Tutoria , Feminino , Humanos , Liderança , Mentores
10.
J Cardiovasc Electrophysiol ; 20(2): 221-3, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18691231

RESUMO

Significant injury to the esophagus during ablation for atrial fibrillation is rare but may be devastating. Esophageal fistulas and injury to branches of the vagus nerve resulting in gastric stasis have previously been described. In this case report, we describe another type of esophageal injury associated with catheter ablation for atrial fibrillation. The patient experienced chest pain and vomiting on recovery from anesthesia. Echocardiography and computerized tomography were used to identify a large esophageal hematoma. The hematoma was treated conservatively and the patient recovered fully after several weeks.


Assuntos
Fibrilação Atrial/patologia , Fibrilação Atrial/cirurgia , Ablação por Cateter , Doenças do Esôfago/patologia , Hemorragia Gastrointestinal/patologia , Idoso , Fibrilação Atrial/diagnóstico por imagem , Dor no Peito/complicações , Eletrocardiografia , Doenças do Esôfago/diagnóstico por imagem , Feminino , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemodinâmica/fisiologia , Humanos , Veias Pulmonares/fisiopatologia , Tomografia Computadorizada por Raios X , Ultrassonografia , Vômito/complicações
11.
Stud Health Technol Inform ; 264: 1728-1729, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438314

RESUMO

This systematic review examined studies aimed at reducing anxiety or depression in African American adults through use of telehealth interventions. Three small independent studies were identified. The findings showed significant reduction of depressive symptoms post-intervention (all p values < .05). However, effectiveness of telehealth intervention compared to face-to-face was not determined. The results highlight the need for additional research into the effectiveness of using telehealth to manage anxiety and depression in this population.


Assuntos
Telemedicina , Adulto , Negro ou Afro-Americano , Ansiedade , Depressão , Humanos
12.
Islets ; 11(3): 65-75, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31149871

RESUMO

Immunologic and non-immunologic loss of islet cells upon their transplantation into the liver leads to suboptimal outcomes. Anti-inflammatory agents are used during autologous and allogeneic transplantation. The aim of this qualitative systematic literature review is to evaluate their clinical use and safety. Electronic databases Embase, PubMed, Cumulative Index for Nursing and Allied Health Literature, ClinicalTrials.gov, and EU Clinical Trials Register were searched. Of the 216 unique citations, 10 with tumor necrosis factor (TNF) blockers [etanercept (ETA) or infliximab] and 3 with both TNF blockers and an interluekin-1 receptor antagonist [anakinra (ANA)]) were included. Of these, 12 were in allogeneic and one in autologous transplant. Insulin independence with decreased islet cells and number of transfusions were reported with their use. One infection was reported in a group receiving ETA. Analysis suggested that the use of ETA ± ANA have the potential to improve outcomes in islet cell transplant.


Assuntos
Anti-Inflamatórios/uso terapêutico , Transplante das Ilhotas Pancreáticas , Anti-Inflamatórios/efeitos adversos , Humanos , Transplante das Ilhotas Pancreáticas/métodos
13.
Eur J Echocardiogr ; 9(4): 591-4, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18490315

RESUMO

Although the primary cause of constrictive pericarditis is entirely different to that of restrictive cardiomyopathy, the two often present with very similar clinical findings. As such, making the distinction between the two is a diagnostic challenge. We report a case that highlights how tissue Doppler imaging may simplify the distinction between pericardial constriction and myocardial restriction.


Assuntos
Cardiomiopatia Restritiva/diagnóstico por imagem , Ecocardiografia Doppler , Pericardite Constritiva/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Pericardite Constritiva/etiologia , Tuberculose/complicações
14.
Heart Rhythm ; 4(6): 722-30, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17556191

RESUMO

BACKGROUND: Wide electrical pulmonary vein isolation (PVI) with two separate rings of ablation requires extensive ablation on the posterior left atrial wall close to the esophagus. OBJECTIVE: The purpose of this study was to determine the feasibility of PVI using a single ring of radiofrequency ablation lesions. METHODS: Irrigated-tip ablation catheters, deflectable sheaths, and computerized tomographic image integration were used to isolate the pulmonary veins and posterior wall of the left atrium in 41 patients with a single ring of radiofrequency ablation lesions. The procedural details were compared with a consecutive series of 41 historical controls who underwent PVI with two separate rings around the ipsilateral vein pairs. RESULTS: Isolation with a single ring was possible in 39 of 41 cases. Ablation was required within the ring at the venous side of the ridge separating the left atrial appendage and left pulmonary veins (n = 17, 43%) or within the roofline (n = 16, 40%). The length of linear lesions adjacent to the esophagus was shorter in the single-ring group (19 +/- 10 mm vs. 31 +/- 14 mm; P = .01). The procedural times, number of ablation sites, duration of ablation required to achieve PVI, and rhythm outcomes at 6 months were similar in the two groups. CONCLUSIONS: Radiofrequency ablation using an open irrigated-tip ablation catheter can be used to reliably electrically isolate the pulmonary veins with a single large circular lesion. PVI can be achieved with a similar procedural and ablation time. The major problem areas were identified as the roof of the left atrium and the ridge separating the left-sided veins from the left atrial appendage.


Assuntos
Fibrilação Atrial/terapia , Ablação por Cateter , Átrios do Coração/fisiopatologia , Veias Pulmonares/cirurgia , Fibrilação Atrial/fisiopatologia , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
15.
ChemMedChem ; 10(11): 1802-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26388134

RESUMO

In this study the rational design, synthesis, and anticancer activity of quinoline-derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp(3) -C-H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4-trifluoro-3-hydroxy-3-(quinolin-2-ylmethyl)butanoate (1), 2-benzyl-1,1,1-trifluoro-3-(quinolin-2-yl)propan-2-ol (2), and trifluoro-3-(isoquinolin-1-yl)-2-(thiophen-2-yl)propan-2-ol (3). Compounds 2 and 3 were found to be more toxic than compound 1; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2, with an LC50 value of 14.14 µm, has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents.


Assuntos
Álcoois/farmacologia , Antineoplásicos/farmacologia , Descoberta de Drogas , Hidrocarbonetos Fluorados/farmacologia , Quinolinas/farmacologia , Quinolinas/toxicidade , Peixe-Zebra/embriologia , Álcoois/síntese química , Álcoois/química , Álcoois/toxicidade , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Hidrocarbonetos Fluorados/síntese química , Hidrocarbonetos Fluorados/química , Hidrocarbonetos Fluorados/toxicidade , Modelos Animais , Estrutura Molecular , Quinolinas/química , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Tissue Barriers ; 2(4): e944449, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25610755

RESUMO

For as long as the human blood-brain barrier (BBB) has been evolving to exclude bloodborne agents from the central nervous system (CNS), pathogens have adopted a multitude of strategies to bypass it. Some pathogens, notably viruses and certain bacteria, enter the CNS in whole form, achieving direct physical passage through endothelial or neuronal cells to infect the brain. Other pathogens, including bacteria and multicellular eukaryotic organisms, secrete toxins that preferentially interact with specific cell types to exert a broad range of biological effects on peripheral and central neurons. In this review, we will discuss the directed mechanisms that viruses, bacteria, and the toxins secreted by higher order organisms use to enter the CNS. Our goal is to identify ligand-mediated strategies that could be used to improve the brain-specific delivery of engineered nanocarriers, including polymers, lipids, biologically sourced materials, and imaging agents.

18.
J Vis Exp ; (82): 51015, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24429733

RESUMO

Poly(lactic-co-glycolic acid) (PLGA) is a biocompatible member of the aliphatic polyester family of biodegradable polymers. PLGA has long been a popular choice for drug delivery applications, particularly since it is already FDA-approved for use in humans in the form of resorbable sutures. Hydrophobic and hydrophilic drugs are encapsulated in PLGA particles via single- or double-emulsion. Briefly, the drug is dissolved with polymer or emulsified with polymer in an organic phase that is then emulsified with the aqueous phase. After the solvent has evaporated, particles are washed and collected via centrifugation for lyophilization and long term storage. PLGA degrades slowly via hydrolysis in aqueous environments, and encapsulated agents are released over a period of weeks to months. Although PLGA is a material that possesses many advantages for drug delivery, reproducible formation of nanoparticles can be challenging; considerable variability is introduced by the use of different equipment, reagents batch, and precise method of emulsification. Here, we describe in great detail the formation and characterization of microparticles and nanoparticles formed by single- or double-emulsion using the emulsifying agent vitamin E-TPGS. Particle morphology and size are determined with scanning electron microscopy (SEM). We provide representative SEM images for nanoparticles produced with varying emulsifier concentration, as well as examples of imaging artifacts and failed emulsifications. This protocol can be readily adapted to use alternative emulsifiers (e.g. poly(vinyl alcohol), PVA) or solvents (e.g. dichloromethane, DCM).


Assuntos
Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Vitamina E/química , Emulsões/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
20.
Circ Arrhythm Electrophysiol ; 5(5): 968-77, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22972873

RESUMO

BACKGROUND: Electric isolation of the pulmonary veins and posterior left atrium with a single ring of radiofrequency lesions (single-ring isolation [SRI]) may result in fewer atrial fibrillation (AF) recurrences than wide antral pulmonary vein isolation (wide antral isolation [WAI]) by abolishing extravenous AF triggers. The effect of mitral isthmus line (MIL) ablation on outcomes after SRI has not previously been assessed. METHODS AND RESULTS: We randomly assigned 220 consecutive patients (58 ± 10 years old; 82% men) with highly symptomatic AF (61% paroxysmal, 39% persistent/longstanding persistent) to undergo either SRI or WAI. Half of each cohort was also randomly allocated to have left lateral MIL ablation (2 ×2 factorial study design). Patients were followed clinically and with 7-day Holter studies for arrhythmia recurrences. The primary end points were recurrence of AF and organized atrial tachyarrhythmias. AF-free survival at 2 years was better after SRI (74% [95% CI, 65%-82%]) than WAI (61% [51%-70%]; P=0.031). Organized atrial tachyarrhythmia-free survival was similar after SRI and WAI (67% [57%-75%] ersus 64% [54%-72%], respectively, at 2 years; P=0.988). MIL ablation resulted in better 2-year organized atrial tachyarrhythmia-free survival (71% [62%-79%] versus 60% [50%-69%]; P=0.07), which approached statistical significance. Survival free of any atrial arrhythmia after one procedure was not significantly affected by isolation technique or MIL ablation. Conclusions- SRI resulted in fewer AF recurrences compared with WAI on long-term follow-up but did not reduce the recurrence of all atrial arrhythmias. MIL ablation may reduce organized atrial tachyarrhythmia recurrences. Clinical Trial Registration- http://www.anzctr.org.au; ACTRN12606000467538.


Assuntos
Fibrilação Atrial/cirurgia , Átrios do Coração/cirurgia , Veias Pulmonares/cirurgia , Fibrilação Atrial/fisiopatologia , Eletrocardiografia Ambulatorial , Feminino , Seguimentos , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Recidiva , Taxa de Sobrevida , Resultado do Tratamento
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