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1.
Gynecol Oncol ; 183: 85-92, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38554478

RESUMO

Burnout and its negative sequelae are a persistent problem in gynecologic oncology, threatening the health of our physician workforce. Individual-level interventions such as stress management training, physical activity, and sleep hygiene only partially address this widespread, systemic crisis rooted in the extended work hours and stressful situations associated with gynecologic oncology practice. There is an urgent need for systematic, institution-level changes to allow gynecologic oncologists to continue the crucial work of caring for people with gynecologic cancer. We present recommendations for institution-level changes which are grounded in the framework presented by the National Plan for Health Workforce Well-Being by the National Academy of Medicine. These are aimed at facilitating gynecologic oncologists' well-being and reduction of burnout. Recommendations include efforts to create a more positive and inclusive work environment, decrease administrative barriers, promote mental health, optimize electronic medical record use, and support a diverse workforce. Implementation and regular evaluation of these interventions, with specific attention to at-risk groups, is an important next step.


Assuntos
Esgotamento Profissional , Ginecologia , Oncologia , Oncologistas , Humanos , Esgotamento Profissional/prevenção & controle , Feminino , Ginecologia/normas , Oncologia/normas , Neoplasias dos Genitais Femininos/terapia , Neoplasias dos Genitais Femininos/psicologia , Sociedades Médicas/normas , Promoção da Saúde/métodos
2.
Gynecol Oncol ; 167(2): 354-359, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36064677

RESUMO

OBJECTIVE: To measure wellness and burnout among gynecologic oncology clinicians and identify trends and at-risk populations to inform future interventions. METHODS: Gynecologic oncologist (GO) and advanced practice provider (APP) responses to the 2020 Society of Gynecologic Oncology State of the Society survey were analyzed. The Maslach Burnout Inventory criteria for burnout was used. Work-life balance was scored on a 5-point Likert scale. Chi-square tests were used to compare mental health factors and the prevalence of burnout. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for associations between burnout and gender. RESULTS: 543 survey responses were included for analysis. Most GO (54%) and all APP respondents were female. Female GOs were disproportionately affected by burnout particularly in the Northeast (female(F): 40.9% vs male(M): 19.1%, p = 0.007) and South (F: 42.5% vs M:22.9%, p = 0.01). Burnout in female GOs over 40 was 1.79 (CI: 1.13-2.83; p-value 0.01) times higher than similarly aged males. Females in non-private practice experienced burnout 1.66 times that of males in similar positions (CI: 1.18-2.94; p < 0.0001). Female GOs reported the worst work-life balance across all 5 domains. APPs and female GOs experienced more stress and feeling overwhelmed compared to men. GOs were more reluctant to see a mental health professional (p = 0.0003) or take medication (p = 0.009) than APPs. CONCLUSIONS: Burnout in gynecologic oncology persists in both genders and is felt most acutely by female GOs. APPs are not immune and would benefit from inclusion in future research to mitigate burnout in healthcare clinicians.


Assuntos
Esgotamento Profissional , Elefantes , Oncologistas , Humanos , Masculino , Feminino , Animais , Idoso , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Inquéritos e Questionários , Fatores de Risco
3.
Rev Sci Instrum ; 91(8): 085109, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32872955

RESUMO

Here, we present an integrated ultra-high vacuum apparatus-named MBE-Cluster -dedicated to the growth and in situ structural, spectroscopic, and magnetic characterization of complex materials. Molecular Beam Epitaxy (MBE) growth of metal oxides, e.g., manganites, and deposition of the patterned metallic layers can be fabricated and in situ characterized by reflection high-energy electron diffraction, low-energy electron diffraction, Auger electron spectroscopy, x-ray photoemission spectroscopy, and azimuthal longitudinal magneto-optic Kerr effect. The temperature can be controlled in the range from 5 K to 580 K, with the possibility of application of magnetic fields H up to ±7 kOe and electric fields E for voltages up to ±500 V. The MBE-Cluster operates for in-house research as well as user facility in combination with the APE beamlines at Sincrotrone-Trieste and the high harmonic generator facility for time-resolved spectroscopy.

4.
Gynecol Oncol ; 159(2): 354-358, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32888724

RESUMO

OBJECTIVE: The objective of this study was to assess the rate of discordance between clinical and pathologic tumor size for women with stage IB1 cervical cancer (FIGO 2009 criteria), assess risk factors for discordance, and determine the impact of discordance on oncologic outcomes. METHODS: This was a secondary analysis of a prior multi-institutional retrospective review of patients diagnosed with stage IB1 (FIGO 2009 staging) cervical cancer undergoing radical hysterectomy between 2010 and 2017. Demographic, clinicopathologic, and oncologic data were collected. Pathologic upstaging was defined as having a preoperative diagnosis of stage IB1 cervical cancer with pathology demonstrating a tumor size >4 cm. Demographic and clinicopathologic data was compared using chi-square, fisher exact or 2-sided t-test. Survival was estimated using the Kaplan-Meier method. RESULTS: Of the 630 patients, 77 (12%) were upstaged. Patients who were upstaged had lower rates of preoperative conization (p < .001) or preoperative tumor sizes ≤2 cm (p < .001). Upstaged patients had increased odds of deep stromal invasion, lymphovascular space invasion, positive margins and positive lymph nodes. Almost 88% of upstaged patients received adjuvant therapy compared to 29% of patients with tumors ≤4 cm (odds 18.49, 95% CI 8.99-37.94). Finally, pathologic upstaging was associated with an increased hazard of recurrence (hazard ratio [HR] 1.95, 95% CI 1.03-3.67) and all-cause death (HR 2.31, 95% CI 1.04-5.11). CONCLUSIONS: Pathologic upstaging in stage IB1 cervical cancer is relatively common. Upstaging is associated with an 18-fold increased risk of receipt of adjuvant therapy. Patients undergoing preoperative conization and those with tumors <2 cm had lower risks of upstaging. Improvement in preoperative assessment of tumor size may better inform primary treatment decisions.


Assuntos
Estadiamento de Neoplasias/métodos , Neoplasias do Colo do Útero/patologia , Idoso , Quimioterapia Adjuvante/estatística & dados numéricos , Conização/estatística & dados numéricos , Feminino , Humanos , Histerectomia/estatística & dados numéricos , Excisão de Linfonodo/estatística & dados numéricos , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estudos Retrospectivos , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/cirurgia
5.
Nat Commun ; 9(1): 2206, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880888

RESUMO

The nature of the metal-insulator transition in thin films and superlattices of LaNiO3 only a few unit cells in thickness remains elusive despite tremendous effort. Quantum confinement and epitaxial strain have been evoked as the mechanisms, although other factors such as growth-induced disorder, cation non-stoichiometry, oxygen vacancies, and substrate-film interface quality may also affect the observable properties of ultrathin films. Here we report results obtained for near-ideal LaNiO3 films with different thicknesses and terminations grown by atomic layer-by-layer laser molecular beam epitaxy on LaAlO3 substrates. We find that the room-temperature metallic behavior persists until the film thickness is reduced to an unprecedentedly small 1.5 unit cells (NiO2 termination). Electronic structure measurements using X-ray absorption spectroscopy and first-principles calculation suggest that oxygen vacancies existing in the films also contribute to the metal-insulator transition.

6.
Nat Commun ; 8(1): 1583, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29146896

RESUMO

Exploiting multiferroic BiFeO3 thin films in spintronic devices requires deterministic and robust control of both internal magnetoelectric coupling in BiFeO3, as well as exchange coupling of its antiferromagnetic order to a ferromagnetic overlayer. Previous reports utilized approaches based on multi-step ferroelectric switching with multiple ferroelectric domains. Because domain walls can be responsible for fatigue, contain localized charges intrinsically or via defects, and present problems for device reproducibility and scaling, an alternative approach using a monodomain magnetoelectric state with single-step switching is desirable. Here we demonstrate room temperature, deterministic and robust, exchange coupling between monodomain BiFeO3 films and Co overlayer that is intrinsic (i.e., not dependent on domain walls). Direct coupling between BiFeO3 antiferromagnetic order and Co magnetization is observed, with ~ 90° in-plane Co moment rotation upon single-step switching that is reproducible for hundreds of cycles. This has important consequences for practical, low power non-volatile magnetoelectric devices utilizing BiFeO3.

7.
Adv Mater ; 25(29): 4043-8, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23813784

RESUMO

Atomic engineering of perovskite films and interfaces is significantly improved by in situ optimization of reflection high-energy electron diffraction (RHEED) features resulting from surface BO6 octahedral rotations seen during molecular-beam epitaxy growth. This approach yields Sr-doped manganite films across the phase diagram with magnetotransport properties that are, for the first time, identical to bulk single crystals. Careful structural analysis of manganite/titanate interfaces shows that cation intermixing and unit cell dilations are eliminated, while BO6 rotations and Jahn-Teller-type elongations are nearly completely suppressed at the interface.


Assuntos
Compostos de Cálcio/química , Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Óxidos/química , Titânio/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
8.
Crit Care Med ; 28(7): 2437-44, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10921576

RESUMO

OBJECTIVE: To determine the role of the chemokine, macrophage inflammatory protein (MIP)-2, in the pathogenesis of aspiration-induced lung injury in the rat. DESIGN: Prospective, randomized, controlled animal study. SETTING: University research laboratories. SUBJECTS: Adult, male Long-Evans rats. INTERVENTIONS: Anesthetized rats underwent induction of lung injury by well-described models of aspiration triggered by intra-tracheal delivery of acid alone, gastric particles alone, or the combination. After injury, induction of MIP-2 messenger RNA in whole lungs and immunoreactive MIP-2 in bronchoalveolar lavage (BAL) fluids was determined. The contribution of MIP-2 to BAL fluid chemotactic activity was defined by using an in vitro chemotaxis assay. The in vivo effect of blocking MIP-2 on pulmonary vascular leak, BAL fluid neutrophils, PaO2/FIO2 ratio, and alveolar-arterial oxygen tension gradient in acid-induced lung injury was determined. MEASUREMENTS AND MAIN RESULTS: Induction of MIP-2 messenger RNA and protein over time was observed in response to all three stimuli. A significant portion (25% to 41%) of the chemotactic activity in BAL fluids from injured rats was inhibited by anti-MIP-2 antibody. After acid injury, blocking of MIP-2 was associated with a 53% decrease in BAL fluid neutrophils and a 33% decrease in pulmonary vascular leak. Although acid injury both impaired oxygenation and increased venous admixture, in vivo blocking of MIP-2 was associated with improved oxygenation as well as decreased venous admixture. CONCLUSIONS: MIP-2 was up-regulated during the development of aspiration-induced lung injury in rats. MIP-2 contributed to lung accumulation of neutrophils via a chemotactic mechanism. Although oxygenation and venous admixture are worsened by acid-induced lung injury in vivo, blocking of MIP-2 at the onset of injury improved these physiologic alterations. Because the aspiration event often is witnessed, chemokines may be valid therapeutic targets for inhibiting the subsequent inflammatory response.


Assuntos
Fatores Quimiotáticos/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , Macrófagos , Síndrome do Desconforto Respiratório/imunologia , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiotaxia de Leucócito , Ácido Clorídrico/administração & dosagem , Inalação , Proteínas Inflamatórias de Macrófagos/genética , Proteínas Inflamatórias de Macrófagos/imunologia , Masculino , Neutrófilos/fisiologia , RNA Mensageiro/análise , Ratos , Ratos Long-Evans , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/metabolismo , Regulação para Cima
9.
Am J Physiol Lung Cell Mol Physiol ; 278(6): L1240-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10835330

RESUMO

Previously we have demonstrated that prolonged exposure to 100% ambient oxygen leads to a marked loss in functional lung volume and lung compliance, hypoxemia, and surfactant system abnormalities similar to acute respiratory distress syndrome (ARDS). However, 50% oxygen administration is believed to be safe in most clinical settings. In the present study, we have evaluated the effects of a 24-h exposure to 50% oxygen in rabbits immediately following experimental gastric acid aspiration. Mild hypoxemia, but no changes in mortality, lung volume, lung compliance, surfactant metabolism, or edema formation occurred after 24 h of normoxia postacid aspiration. Conversely, a relatively short (24-h) exposure to 50% oxygen after acid aspiration results in increased pulmonary edema, physical signs of respiratory distress, and mortality, as well as decreased arterial oxygenation, lung volume, lung compliance, and type II alveolar cell surfactant synthesis. These results suggest that acid aspiration alters the "set point" for oxygen toxicity, possibly by "priming" cells through activation of inflammatory pathways. This pathogenic mechanism may contribute to the progression of aspiration pneumonia to ARDS.


Assuntos
Ácido Clorídrico/administração & dosagem , Pulmão/efeitos dos fármacos , Oxigênio/intoxicação , Pneumonia Aspirativa/fisiopatologia , Ar , Animais , Resistência a Medicamentos , Ácido Clorídrico/farmacologia , Pulmão/metabolismo , Concentração Osmolar , Pneumonia Aspirativa/mortalidade , Surfactantes Pulmonares/metabolismo , Coelhos
10.
Infect Immun ; 68(5): 2854-62, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10768982

RESUMO

Enteric gram-negative bacilli cause a severe, often life-threatening pneumonia. An improved understanding of the pathogenesis of this infection may lead to improved treatment. Nearly all of the responsible gram-negative bacilli possess capsular polysaccharides and/or an O-specific antigen as part of their lipopolysaccharide (LPS). We hypothesized that these surface polysaccharides may modulate the pulmonary host response. To investigate this, a rat pneumonitis model was used, and pulmonary neutrophil influx, a critical aspect of host defense, was measured. To assess for the effect of the capsule and O-specific antigen on this host response, three proven, isogenic derivatives that are deficient in capsular polysaccharide alone (CP9.137), the O-specific antigen moiety of the LPS alone (CP921), and both the capsular polysaccharide and O-specific antigen (CP923), as well as their wild-type parent (CP9), were used as challenge strains at various intratracheal challenge inocula (CI). Total lung myeloperoxidase (MPO), a surrogate marker for neutrophils, was measured for 15 h post-bacterial challenge. To determine the effect of capsule and the O-specific antigen on the measured MPO levels, a mathematical model was developed and used to describe the MPO levels as a function of time for each CI of each of the four strains. The results from this analysis demonstrated that in the absence of the K54 capsule, 80.7 times the CI is necessary to achieve the same maximum MPO level relative to K54 positive strains (P < 0.0001). In contrast, a diametric effect was observed in the absence of the O-specific antigen, where 0.13 times the CI was necessary to achieve the same maximum MPO level relative to O4-positive strains (P = 0.0032). No interactive effect was observed between the capsule and the O-specific antigen. These findings demonstrate that these surface polysaccharides modulate pulmonary neutrophil influx and suggest that the K54 capsular polysaccharide is a proinflammatory mediator and that the O4-specific antigen attenuates the proinflammatory response. If these speculations are substantiated, an understanding of how the capsule and the O-specific antigen modulate host response could have significant therapeutic implications. The potential use of biologic modulators directed against the host response, as well as approaches based on inactivating bacterial components (e.g., surface polysaccharides) in attempts to modify sepsis syndromes, could be developed.


Assuntos
Cápsulas Bacterianas/imunologia , Escherichia coli/imunologia , Neutrófilos/imunologia , Antígenos O/imunologia , Pneumonia Bacteriana/imunologia , Animais , Modelos Animais de Doenças , Humanos , Pulmão/citologia , Ratos , Ratos Long-Evans
11.
Anesth Analg ; 90(2): 356-61, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10648321

RESUMO

UNLABELLED: Perflurocarbons (PFCs) are used during liquid ventilation and as hemoglobin substitutes. PFCs reduce free radical generation and damage to the lung during liquid ventilation. Thus, we examined the effects of parenteral administration of PFCs on lung injury after acid aspiration. Rats were treated with intraperitoneal injection of either FC-77 or IV injection of Fluosol. Controls received intraperitoneal or IV normal saline (NS) before or at the time of injury and then were injured by instillation of NS + HCl (pH = 1.25) into their lungs via a tracheotomy. The animals were exposed to air or 98% oxygen, breathing spontaneously. The rats were injected with 0.05 microCi of (125)I-albumin (bovine serum albumin) before injury. The extent of lung injury was assessed 5 h postinjury by compliance and lung albumin permeability index measurement. Myeloperoxidase (MPO) activity and histologic examination were used to assess neutrophilic infiltration. Both FC-77 and Fluosol decreased the permeability index compared with controls (1.05 +/- 0.08; 1.08 +/- 0. 12, respectively, versus 1.34 +/- 0.21) and improved lung compliance after intratracheal instillation of 1.2 mL/kg of HCl/NS, pH = 1.25 + hyperoxia injury (P < 0.05). Lung MPO activity decreased in the FC-77 group and was associated with a concomitant decrease in neutrophil infiltration. MPO activity of the spleen increased after FC-77 treatment. The administration of FC-77 decreased the severity of lung permeability changes associated with acid in the presence or absence of hyperoxia exposure. These data suggest that attenuation of neutrophilic infiltration by PFCs decreases lung injury. IMPLICATIONS: Intraperitoneally administered perfluorocarbons in rats attenuate the neutrophilic infiltration in the lung after acid aspiration, thereby decreasing the alveolar protein leakage and improving pulmonary compliance.


Assuntos
Fluorocarbonos/uso terapêutico , Ácido Gástrico , Pneumonia Aspirativa/tratamento farmacológico , Animais , Hiperóxia/tratamento farmacológico , Hiperóxia/fisiopatologia , Contagem de Leucócitos , Leucopenia/patologia , Pulmão/enzimologia , Pulmão/patologia , Complacência Pulmonar/efeitos dos fármacos , Masculino , Neutrófilos/patologia , Peroxidase/metabolismo , Pneumonia Aspirativa/fisiopatologia , Alvéolos Pulmonares/patologia , Ratos , Ratos Long-Evans , Baço/enzimologia
12.
Anesthesiology ; 91(3): 741-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10485786

RESUMO

BACKGROUND: Inhaled nitric oxide is often used in patients with adult respiratory distress syndrome. However, nitric oxide also may be significantly toxic, especially if administered concurrently with hyperoxia. The authors evaluated the isolated effect of nitric oxide and the combined effects of nitric oxide and hyperoxia on lung injury in rats after acid aspiration. METHODS: Animals were injured by instillation of 1.2 ml/kg hydrogen chloride in low-pH saline (the acid group) or acidified gastric particles (the casp group) into the lungs under halothane anesthesia via a tracheal catheter. Controls received no injury vehicle but rather underwent the surgical process. After recovery from anesthesia, the animals were exposed to 20% or 90% oxygen with or without 20, 40, or 80 ppm nitric oxide for 5 h. The permeability index, alveolar-arterial oxygen difference, the ratio of oxygen pressure to the inspired fraction of oxygen, and the ratio of wet to dry weight were assessed 5 h after injury as indices of lung injury. Data were assessed using analysis of variance. RESULTS: Each group included 6-10 rats. Exposure to nitric oxide (80 ppm) in air increased protein permeability in the lungs to a permeability index of 1.42+/-0.12 after acid aspiration. The combination of nitric oxide (80 ppm) and hyperoxia further increased protein leakage to a permeability index of 2.1+/-0.25. Exposure to lower concentrations of nitric oxide (e.g., 20 and 40 ppm) increased the permeability index of the lungs (1.44+/-0.21, 1.75+/-0.29, respectively) in the presence of hyperoxia, although it did not affect the permeability index of the lungs during exposure to air. Pretreatment of animals with deferoxamine and methylene blue partially inhibited the adverse effect of hyperoxia and nitric oxide, which suggested a complex underlying mechanism involving both reactive-species generation and pulmonary vasomotor changes. CONCLUSIONS: These results show that inhaled nitric oxide at 80 ppm for a short duration (5 h) increases the severity of the inflammatory microvascular lung injury after acid aspiration. The pulmonary damage is exacerbated further in the presence of high oxygen concentrations. Although lower concentrations of nitric oxide did not increase the extent of lung injury, longer exposure times need to be assessed.


Assuntos
Pulmão/efeitos dos fármacos , Óxido Nítrico/toxicidade , Pneumonia Aspirativa/complicações , Administração por Inalação , Animais , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Masculino , Azul de Metileno/farmacologia , Óxido Nítrico/administração & dosagem , Oxigênio/toxicidade , Permeabilidade , Proteínas/metabolismo , Ratos , Ratos Long-Evans
13.
Anesthesiology ; 91(2): 486-99, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10443613

RESUMO

BACKGROUND: Aspiration pneumonitis is characterized by proteinaceous pulmonary edema and acute infiltration of neutrophils into the alveolar space. This study examined the role of the proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), on the pathogenesis of the injury produced by the different components that may be present in the aspirate, acid, or gastric particles. METHODS: Rats were injured by intratracheal instillation of a vehicle containing acid or gastric particles. TNF-alpha concentration of bronchoalveolar lavage fluid was determined using a bioassay. upregulation of lung TNF-alpha mRNA was also measured. The effect of intratracheal anti-rat TNF-alpha treatment was assessed by lung protein permeability, blood gases, and lung myeloperoxidase activity. RESULTS: Injury vehicle alone and acid injury resulted in a small TNF-alpha peak 1-2 h after injury in the lavage fluid. Both particulate and acidic particulate groups produced a much more robust TNF-alpha signal that reached a plateau at 2-4 h after injury and declined at 8 h. Upregulation of TNF-alpha mRNA was only detected in the particulate-containing groups. Acidic particulate exposure yielded a synergistic increase in protein permeability and decrease in blood oxygenation. Anti-TNF-alpha treatment reduced protein permeability and myeloperoxidase activity and increased blood oxygenation in the groups exposed to only acid. Such treatment had no effect on either of the particulate containing injuries. CONCLUSIONS: TNF-alpha is differentially manifested according to the components that make up the aspirate but the levels of TNF-alpha expression do not correlate with the severity of the resultant injury. However, the reduction in acid-induced lung injury by anti-TNF-alpha treatment indicates that TNF-alpha plays a role in the pathogenesis of aspiration pneumonitis.


Assuntos
Pneumonia Aspirativa/etiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Anticorpos/imunologia , Northern Blotting , Líquido da Lavagem Broncoalveolar/química , Hiperóxia/complicações , Pulmão/metabolismo , Masculino , Neutrófilos/fisiologia , Proteínas/metabolismo , Ratos , Ratos Long-Evans , Fator de Necrose Tumoral alfa/análise
14.
Anesth Analg ; 87(1): 127-33, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9661561

RESUMO

UNLABELLED: Hyperoxia increases pulmonary damage after acid aspiration. We hypothesize that free radicals play a role in acute lung injury. To examine this hypothesis, we injured rats by intratracheal instillation of acidic isotonic sodium chloride solution (NS) (pH 1.25); NS + gastric particles (particle pH 5.3); or acid + particles (pH 1.25). Animals were exposed to 98% oxygen or air for 5 h. Superoxide (HO2) generation was measured in either an aliquot of white blood cells (WBCs) recovered from bronchoalveolar lavage (BAL) or from blood. Lungs were analyzed for thiobarbituric acid-reactive substances (TBARS) and carbonylated proteins. The antioxidant capacity was measured using a 2-2'-azo-bis-amidinopropane hydrochloride neutralizing assay. Generation of HO2 by WBCs in peripheral blood was greater in animals exposed to 98% O2 (89.8 +/- 12.5 U. min-1.10(5) neutrophils) compared with air exposure (37.5 +/- 9.2 U.min-1.10(5) neutrophils) after combined injury (P < 0.05). Similarly, HO2 generation by WBCs retrieved from BAL was higher in oxygen-exposed rats (987.74 +/- 128 U.min-1.10(5) WBC) compared with air-exposed animals after an identical injury (348 +/- 9.2 U. min-1.10(5) WBC) (P < 0.05). TBARS and carbonylated protein levels in the lungs of oxygen-exposed animals (587.9 +/- 58.6 and 55.8 +/- 3.1 pmol/mg of protein, respectively) were higher than those in air-exposed rats after combined injury (342.8 +/- 15.1 and 28.6 +/- 4.6 pmol/mg of protein, respectively) and compared with air-exposed uninjured rats (340.6 +/- 9.8 and 18.3 +/- 2.8 pmol/mg of protein, respectively; P < 0.01). Antioxidant capacity decreased in acid and combined injury groups (2.41 +/- 0.13 min and 1.94 +/- 0.15 min, respectively) compared with the uninjured group after 5 h of exposure to 98% oxygen (4.85 +/- 0.19 min; P < 0.01). We demonstrated evidence of increased oxidant activity on lipids and proteins in injured lungs after oxygen exposure. The decrease in antioxidant capacity after low pH aspiration with exposure to hyperoxia may contribute to this increase. IMPLICATIONS: Oxygen administration results in a lung pathology known as oxygen toxicity. This effect is usually not significant if the duration of exposure is limited to < 24 h. In the presence of acute inflammatory lung injury, exposure to hyperoxia results in lung damage in a shorter time. We demonstrate that sufficiently decreased lung antioxidant reserve capacity may be accountable for this early toxicity.


Assuntos
Pneumopatias/metabolismo , Oxigênio/toxicidade , Pneumonia Aspirativa/complicações , Pneumonia Aspirativa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Líquido da Lavagem Broncoalveolar , Concentração de Íons de Hidrogênio , Contagem de Leucócitos , Leucócitos/metabolismo , Peroxidação de Lipídeos , Pneumopatias/sangue , Pneumopatias/etiologia , Masculino , Neutrófilos/metabolismo , Oxigênio/metabolismo , Pneumonia Aspirativa/sangue , Ratos , Ratos Endogâmicos , Superóxidos/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Chest ; 112(6): 1607-14, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9404761

RESUMO

OBJECTIVES: To examine the effects of an increase in ambient oxygen (O2) concentrations on the extent of inflammatory pulmonary damage following acid aspiration. DESIGN: Prospective, controlled laboratory study. SETTINGS: University-affiliated animal research facility. SUBJECTS: Male, Long Evans rats weighing 250 to 300 g. INTERVENTION: Rats were injured by instillation of 1.2 mL/kg normal saline solution/HCl, pH= 1.25 (acid), into the lungs via a tracheotomy. Animals were allowed to awaken and were exposed to 21%, 50%, or 98% O2 for 0 to 5 h (n/group > or = 10). In a separate set of experiments, injured rats exposed to 98% O2 were treated with different doses of deferoxamine, just prior to injury. Uninjured rats and rats injured with normal saline solution, pH = 5.3, were used as the control group. MEASUREMENTS: Injury was determined by assessing lung function (lung compliance and arterial blood gases) and alveolar-capillary wall integrity (wet/dry weight, lung albumin permeability index [PI], and intrapulmonary hemorrhage [HI]). RESULTS: Intrapulmonary instillation of acid increased PI, HI, and decreased static lung compliance compared to uninjured control animals. Increased ambient oxygen following acid aspiration decreased lung compliance, 1.06+/-0.03 mL/kg/cm H2O, in oxygen-exposed lungs when compared to the lungs exposed to air, 1.26+/-0.04, following a low pH aspirate (p<0.05). An increase in protein leakage into the lung tissue was noted in oxygen-exposed animals, PI=1.33+/-0.10, vs air-exposed rats, 0.89+/-0.07 (p<0.05). The hyperoxia-induced increase in lung injury was prevented by 30 mg/kg or higher deferoxamine treatment, 0.78+/-0.05 (p<0.05). Exposure of animals to 98% O2 for 2 h was sufficient to produce the same increase in microvascular protein leakage as 5-h exposure to O2 following low pH aspirate. CONCLUSION: Hyperoxia increases acid aspiration-induced inflammatory microvascular lung injury. This appears to be mediated by production of reactive species of O2.


Assuntos
Hiperóxia/fisiopatologia , Pulmão/irrigação sanguínea , Pneumonia Aspirativa/fisiopatologia , Síndrome do Desconforto Respiratório/fisiopatologia , Animais , Barreira Alveolocapilar/fisiologia , Capilares/fisiopatologia , Ácido Gástrico , Concentração de Íons de Hidrogênio , Complacência Pulmonar , Masculino , Pneumonia Aspirativa/etiologia , Estudos Prospectivos , Ratos , Ratos Endogâmicos , Síndrome do Desconforto Respiratório/etiologia , Organismos Livres de Patógenos Específicos , Fatores de Tempo
16.
Aesthet Surg J ; 17(4): 264-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-19327725

RESUMO

I believe it is desirable to maintain continuity of the pectoralis major muscle to the maximal extent when performing subpectoral breast augmentation. Strong, upward lifting and stretching of the muscle belly facilitates a smooth, natural contour and eliminates the need to cut or avulse the sternal origin of the muscle, thereby preserving strength and reducing bleeding.

17.
Plast Reconstr Surg ; 95(6): 1108-10, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7732124

RESUMO

A case is presented in which the upper lip of a 20-year-old woman was augmented by a graft of palmaris longus tendon-muscle. This technique offers several advantages over other lip enlargement techniques. The primary drawback, in my opinion, is the possibility that lip excursion (smiling, animation) might be restricted by tendon-muscle adherence to lip tissues, although this did not occur in this patient. Experience with larger numbers of patients is necessary before this technique can be endorsed for general use.


Assuntos
Lábio/cirurgia , Cirurgia Plástica/métodos , Tendões/transplante , Adulto , Feminino , Antebraço , Humanos
19.
Anesthesiology ; 79(1): 73-82, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8393631

RESUMO

BACKGROUND: Enflurane and isoflurane may reduce cardiac contractility by altering mobilization and clearance of intracellular Ca2+ (Ca2+i). It was hypothesized that the negative inotropic actions of these agents involve limiting both membrane Ca2+ entry and altering intracellular Ca2+ release. METHODS: The Ca2+i transients in rat ventricular myocytes loaded with fura-2 were recorded from a fluorescence microscope. Transients stimulated by membrane depolarization (suction electrode or elevated [K+]o) or 15 mM caffeine to release Ca2+ from the sarcoplasmic reticulum (SR) were analyzed for net amplitude, maximal rate of rise (VR), average rate of decline (VR) in [Ca2+]i, and duration. RESULTS: Enflurane and isoflurane reduced electrically stimulated Ca2+i transients in a dose-dependent manner. Enflurane depressed the Ca2+i transient amplitude more than isoflurane. Enflurane was more effective than isoflurane in reducing VR and VF in a concentration-dependent manner. At similar concentrations, both enflurane and isoflurane reduced the steady state elevation of [Ca2+]i by 50 mM K+o. Similarly, enflurane and isoflurane depressed caffeine-sensitive release of Ca2+ from the SR. The reduction in the Ca2+i transient because of SR Ca2+ release was greater in enflurane than in equal concentrations of isoflurane. Rates of elevation and decline in [Ca2+]i were also reduced in enflurane and isoflurane. CONCLUSIONS: The negative inotropic actions of enflurane and isoflurane involve a depression of Ca2+ influx during membrane excitation, as well as a reduction in SR Ca2+ release. Slowed rates of elevation in [Ca2+]i indicate that the latter mechanism may, in part, be caused by alterations in the kinetics of SR Ca2+ release.


Assuntos
Cálcio/metabolismo , Enflurano/farmacologia , Coração/efeitos dos fármacos , Isoflurano/farmacologia , Miocárdio/metabolismo , Animais , Cafeína/farmacologia , Canais de Cálcio/metabolismo , Células Cultivadas , Interações Medicamentosas , Estimulação Elétrica , Feminino , Técnicas In Vitro , Líquido Intracelular/metabolismo , Miocárdio/citologia , Potássio/farmacologia , Ratos , Ratos Sprague-Dawley , Sarcolema/efeitos dos fármacos , Sarcolema/metabolismo , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Estimulação Química
20.
Anesth Analg ; 76(5): 1106-13, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8484515

RESUMO

The effect of halothane anesthesia on the influenza A specific immune response and the pathogenesis of infection was evaluated in mice. Three-wk-old CD-1 mice were anesthetized with either 2% halothane for 2 h or ketamine (100 mg/kg intraperitoneally) and subsequently inoculated intranasally with a sublethal dose of influenza type A/PR/8/34 virus. Bronchoalveolar lavage was performed on animals from each group at 4 h postinoculation and daily thereafter for 14 days. Total and differential white blood cell counts were measured in the lavage fluid and the lungs were examined histologically for evidence of injury. Infected mice anesthetized with halothane had lower daily cell counts in the lung than animals anesthetized with ketamine and a marked change in cell type distribution. On Days 4 and 11 postinoculation, there were significantly (P < 0.05) more white blood cells in the lavage fluid of animals anesthetized with ketamine than halothane (mean/mL, 738,000 +/- SEM, 128,000 vs 196,000 +/- 51,400, respectively, and 1,020,000 +/- 227,000 vs 117,000 +/- 34,600, respectively). Differential counts were significantly higher (P < 0.05) in the ketamine group compared to the halothane for neutrophils on Day 4 (452,000 +/- 77,900 vs 72,000 +/- 46,000, respectively) and on Day 11 for lymphocytes (340,000 +/- 59,000 vs 33,000 +/- 17,000, respectively) and macrophages (480,000 +/- 120,000 vs 130,000 +/- 61,000). Infected mice that were given ketamine were qualitatively "sicker" than the halothane-treated group as evidenced by the appearance of ruffled fur, tachypnea, and cachexia. Animals anesthetized with ketamine demonstrated a greater degree of pulmonary histopathology including diffuse infiltration of macrophages, neutrophils, hemorrhage, and fibrin deposition.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Halotano/farmacologia , Vírus da Influenza A , Infecções por Orthomyxoviridae/imunologia , Alvéolos Pulmonares/microbiologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Ketamina/farmacologia , Contagem de Leucócitos , Macrófagos Alveolares , Masculino , Camundongos , Neutrófilos , Infecções por Orthomyxoviridae/patologia , Alvéolos Pulmonares/efeitos dos fármacos , Organismos Livres de Patógenos Específicos
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