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1.
Respir Res ; 25(1): 323, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39182102

RESUMO

BACKGROUND: Complicated pleural infection comprises of complex effusions and empyema. When tube thoracostomy is ineffective, treatment options include surgical drainage, deloculation and decortication or intrapleural fibrinolysis. We performed a systematic review and meta-analysis to examine which technique is superior in treating complicated pleural infections. METHODS: PubMed, MEDLINE and EMBASE databases were searched for studies published between January 2000 to July 2023 comparing surgery and intrapleural fibrinolysis for treatment of complicated pleural infection. The primary outcome was treatment success. Secondary outcomes included hospital length of stay, chest drain duration and in-hospital mortality. RESULTS: Surgical management of complicated pleural infections was more likely to be successful than intrapleural fibrinolysis (RR 1.18; 95% CI 1.02, 1.38). Surgical intervention group benefited from statistically significant shorter hospital length of stay (MD: 3.85; 95% CI 1.09, 6.62) and chest drain duration (MD: 3.42; 95% CI 1.36, 5.48). There was no observed difference between in-hospital mortality (RR: 1.00; 95% CI 0.99, 1.02). CONCLUSION: Surgical management of complicated pleural infections results in increased likelihood of treatment success, shorter chest drain duration and hospital length of stay in the adult population compared with intrapleural fibrinolysis. In-hospital mortality did not differ. Large cohort and randomized research need to be conducted to confirm these findings.


Assuntos
Terapia Trombolítica , Humanos , Terapia Trombolítica/métodos , Empiema Pleural/cirurgia , Empiema Pleural/mortalidade , Empiema Pleural/diagnóstico , Resultado do Tratamento , Mortalidade Hospitalar , Drenagem/métodos , Tempo de Internação , Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêutico , Fibrinólise/efeitos dos fármacos , Derrame Pleural/cirurgia , Derrame Pleural/terapia
2.
Heart Lung Circ ; 33(9): 1250-1258, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38981829

RESUMO

BACKGROUND: Routine screening chest computed tomography (CT) prior to primary cardiac surgery is advocated by some surgeons due to the purported benefits of identifying significant aortic calcification that impacts ongoing management, such as performing anaortic off-pump surgery or adjusting cannulation strategy. Additionally, axial imaging can identify incidental findings that may require concomitant or staged procedures such as ascending aortic dilatation or pulmonary lesions. The objective of this study was to quantify the impact that nonselective chest CT prior to primary cardiac surgery had on subsequent management. METHOD: A systematic review and pooled prevalence meta-analyses were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Included studies performed non-selective chest CT prior to primary cardiac surgery. RESULTS: A total of eight studies, including 2,250 patients were included. The rate of mortality and stroke was low (1% and 2%, respectively). Calcification of the ascending aorta was identified in 15% of patients (95% confidence interval [CI] 5.0-26.0). A significant change to the surgical plan such as cannulation strategy, off-pump surgery, cancellation, or an additional procedure was required in 7% (95% CI 2.0-12.0). Clinically relevant incidental findings requiring in-patient management or follow-up were identified in 10% (95% CI 6.0-14.0). CONCLUSIONS: Nonselective CT chest prior to primary cardiac surgery identifies clinically relevant findings that result in a modification of the surgical plan in a significant population of patients to address the risk of stroke associated with aortic calcification as well as the identification of important incidental findings such as pulmonary lesions.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cuidados Pré-Operatórios , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Procedimentos Cirúrgicos Cardíacos/métodos , Prevalência , Cuidados Pré-Operatórios/métodos
3.
J Card Surg ; 37(1): 197-204, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34665474

RESUMO

BACKGROUND: Frailty is associated with poorer outcomes in cardiac surgery, but the heterogeneity in frailty assessment tools makes it difficult to ascertain its true impact in cardiac surgery. Slow gait speed is a simple, validated, and reliable marker of frailty. We performed a systematic review and meta-analysis to examine the effect of slow gait speed on postoperative cardiac surgical patients. METHODS: PubMED, MEDLINE, and EMBASE databases were searched from January 2000 to August 2021 for studies comparing slow gait speed and "normal" gait speed. Primary outcome was in-hospital mortality. Secondary outcomes were composite mortality and major morbidity, AKI, stroke, deep sternal wound infection, prolonged ventilation, discharge to a healthcare facility, and ICU length of stay. RESULTS: There were seven eligible studies with 36,697 patients. Slow gait speed was associated with increased likelihood of in-hospital mortality (risk ratio [RR]: 2.32; 95% confidence interval [CI]: 1.87-2.87). Additionally, they were more likely to suffer from composite mortality and major morbidity (RR: 1.52; 95% CI: 1.38-1.66), AKI (RR: 2.81; 95% CI: 1.44-5.49), deep sternal wound infection (RR: 1.77; 95% CI: 1.59-1.98), prolonged ventilation >24 h (RR: 1.97; 95% CI: 1.48-2.63), reoperation (RR: 1.38; 95% CI: 1.05-1.82), institutional discharge (RR: 2.08; 95% CI: 1.61-2.69), and longer ICU length of stay (MD: 21.69; 95% CI: 17.32-26.05). CONCLUSION: Slow gait speed is associated with poorer outcomes in cardiac surgery. Frail patients are twofold more likely to die during hospital admission than nonfrail counterparts and are at an increased risk of developing various perioperative complications.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Fragilidade , Mortalidade Hospitalar , Humanos , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia , Velocidade de Caminhada
4.
Heart Surg Forum ; 25(5): E652-E659, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36317908

RESUMO

OBJECTIVE: Frailty is an increasingly recognized marker of poor surgical outcomes in cardiac surgery. Frailty first was described in the seminal "Fried" paper, which constitutes the longest-standing and most well-recognized definition. This study aimed to assess the impact of the Fried and modified Fried frailty classifications on patient outcomes following cardiac surgery. METHODS: The PUBMED, MEDLINE, and EMBASE databases were searched from January 2000 until August 2021 for studies evaluating postoperative outcomes using the Fried or modified Fried frailty indexes in open cardiac surgical procedures. Primary outcomes were one-year survival and postoperative quality of life. Secondary outcomes included postoperative complications, intensive care unit (ICU) length of stay (LOS), total hospital LOS, and institutional discharge. RESULTS: Eight eligible studies were identified. Meta-analysis identified that frailty was associated with an increased risk of one-year mortality (Risk Ratio [RR]:2.23;95% confidence interval [CI]1.17 -4.23), postoperative complications (RR 1.78;95% CI 1.27 - 2.50), ICU LOS (Mean difference [MD] 21.2 hours;95% CI 8.42 - 33.94), hospital LOS (MD 3.29 days; 95% CI 2.19 - 4.94), and institutional discharge (RR 3.29;95% CI 2.19 - 4.94). A narrative review of quality of life suggested an improvement following surgery, with frail patients demonstrating a greater improvement from baseline over non-frail patients. CONCLUSIONS: Frailty is associated with a higher degree of surgical morbidity, and frail patients are twice as likely to experience mortality within one-year post-operatively. Despite this, quality of life also improves dramatically in frail patients. Frailty, in itself, does not constitute a contraindication to cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Fragilidade , Humanos , Fragilidade/complicações , Qualidade de Vida , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Fenótipo
5.
Biochem Biophys Res Commun ; 556: 53-58, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33839414

RESUMO

Interleukin 15 receptor (IL-15R) is a transmembrane signalling protein consisting of 3 subsets: α, ß (IL-15Rß), and γ (γc). IL-2 and IL-15 share the signalling domains IL-15Rß and γc, although they bind to intrinsic α-subsets and non-signalling domains. Additionally, IL-2 and IL-15 play different roles; therefore, there have been many observations of the dynamic behaviours of IL-15R, which are linked to physiological functions. For more practical discrimination between IL-2 and IL-15, a study was designed and carried out in which α-subsets were removed and a cytoplasmic inhibitor was applied to create a simplified environment in which secondary signalling molecules were reduced. We also applied a new measurement method, diffracted X-ray blinking (DXB), to achieve higher accuracy (<0.01 Å). The dynamics of IL-2 binding (confined motion, max range = 0.71 Å) and IL-15 binding (normal motion) in live natural killer cells were different. We also confirmed. that DXB was a suitable method to quantitatively evaluate the transmembrane protein dynamics of inner/outer live cell membranes by labeling the extracellular domain since the measurements were dependent on the cytosolic environment.


Assuntos
Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Receptores de Interleucina-15/análise , Receptores de Interleucina-15/metabolismo , Difração de Raios X/métodos , Sobrevivência Celular , Difusão , Humanos , Hidroxibenzoatos , Interleucina-15/metabolismo , Interleucina-2/metabolismo , Simulação de Dinâmica Molecular , Nitrofuranos , Domínios Proteicos , Especificidade por Substrato
6.
Horm Behav ; 78: 60-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26497249

RESUMO

Age-related changes in reproductive hormone levels are a well-known risk factor for the development of cognitive dysfunction and dementia in women. We and others have shown an important contribution of gonadotropins in this process. Lowering serum gonadotropin levels is able to rescue cognitive function in Alzheimer's disease and menopause models, but whether this is time-dependent and the exact mechanism through which gonadotropins regulate cognitive function is unknown. We show that pharmacologically lowering serum levels of luteinizing hormone lead to cognitive improvement immediately after ovariectomy and with a 4month interval after ovariectomy, when the benefits of 17ß-estradiol are known to disappear in rodents. Importantly, we show that these improvements are associated with spine density changes at both time points. These findings suggest a role of luteinizing hormone in learning and memory and neuroplasticity processes as well as provide an alternative therapeutic strategy of menopause associated cognitive loss.


Assuntos
Densidade Óssea/efeitos dos fármacos , Cognição/efeitos dos fármacos , Estrogênios/farmacologia , Hormônio Luteinizante/sangue , Ovariectomia/efeitos adversos , Animais , Cognição/fisiologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/prevenção & controle , Regulação para Baixo/efeitos dos fármacos , Estradiol/sangue , Estradiol/farmacologia , Terapia de Reposição de Estrogênios , Feminino , Camundongos Endogâmicos C57BL , Osteoporose/etiologia , Osteoporose/prevenção & controle , Ovariectomia/psicologia , Reprodução/efeitos dos fármacos , Coluna Vertebral/efeitos dos fármacos , Fatores de Tempo
7.
J Neurochem ; 130(1): 115-25, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24601954

RESUMO

Development of Alzheimer's disease (AD) has been linked to the de-regulation of estrogen and gonadotropins such as luteinizing hormone (LH). In this study, we found increases in AD pathology in the hippocampi of aged female 3xTg AD mice after ovariectomy that were unable to be reduced by estrogen therapy or down-regulation of serum LH levels. Despite the lack of effect of these treatments on AD pathology, down-regulation of serum LH but not estrogen improved factors associated with neuronal plasticity such as spatial memory, inhibition of glycogen synthase kinase-3 beta, expression of beta-catenin, and brain-derived neurotrophic factor transcription. Contrasting previous studies in younger mice, estrogen replacement was not able to rescue behavioral deficits, reduced glycogen synthase kinase-3 beta inhibition and increased hippocampal phosphorylation of tau. Of critical importance, serum LH was negatively correlated with brain LH in regions associated with spatial memory, and increases in brain LH correlated with cognitive improvement. This paralleled changes in human female AD brains which showed a significant reduction in brain LH mRNA compared to healthy age- and PMI-matched controls. Taken together, these findings should promote further research into the LH-dependent mechanisms associated with AD cognitive deficits as well as the effects of estrogen within the aged brain. In the aged triple transgenic Alzheimer's disease (AD) mouse model (3xAD-Tg), estrogen replacement after ovariectomy does not improve cognitive function, increases phosphorylated Tau levels and decreases inhibition of GSK3 beta. Luprolide acetate rescues ovariectomy-dependent cognitive function, increases signaling events associated with synaptic plasticity including GSK3 beta inhibition, but does not alter AD pathology. In the human AD female brain, luteinizing hormone (LH) mRNA levels are reduced. In the 3XAD-tg model, brain LH protein levels are reduced by ovariectomy and normalized by leuprolide acetate treatment. These treatment-dependent normalization of LH positively correlates with markers of neuroplasticity and cognitive improvement.


Assuntos
Envelhecimento/sangue , Cognição/fisiologia , Regulação para Baixo/fisiologia , Terapia de Reposição de Estrogênios/métodos , Estrogênios/administração & dosagem , Hormônio Luteinizante/sangue , Ovariectomia , Animais , Biomarcadores/sangue , Células Cultivadas , Feminino , Gonadotropinas/sangue , Hipocampo/metabolismo , Camundongos , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley
8.
Artigo em Inglês | MEDLINE | ID: mdl-37615693

RESUMO

Video-assisted thoracoscopic sympathicotomy is the most widely used technique in the modern era for the treatment of primary hyperhidrosis. Primary hyperhidrosis is characterized by excessive sweating and significantly affects the quality of life in those who suffer from it. This video tutorial details a uniportal, drainless sympathicotomy performed by the cardiothoracic surgical team at St George Hospital, Sydney, Australia.


Assuntos
Hiperidrose , Qualidade de Vida , Humanos , Hiperidrose/cirurgia
9.
Local Reg Anesth ; 16: 81-90, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37334278

RESUMO

Introduction: Rib fractures are a common sequelae of chest trauma and are associated with significant morbidity. The erector spinae nerve block (ESB) has been proposed as an alternative first-line regional technique for rib fractures due to ease of administration and minimal complication profile. We aimed to investigate the current literature surrounding this topic with a focus on pain and respiratory outcomes. Methods: A comprehensive literature search was performed on the Medline, Embase, Web of Science, Scopus, and Cochrane databases. Keywords of "erector spinae block" and "rib fractures" were used to form the search strategy. Papers published in English investigating ESB as an analgesic intervention for acute rib fracture were included. Exclusion criteria were operative rib fixation, or where the indication for ESB was not rib fracture. Results: There were 37 studies which met the inclusion criteria for this scoping review. Of these, 31 studies reported on pain outcomes and demonstrated a 40% decrease in pain scores post administration within the first 24 hours. Respiratory parameters were reported in 8 studies where an increase in incentive spirometry was demonstrated. Respiratory complication was not consistently reported. ESB was associated with minimal complications; only 5 cases of haematoma and infection were (incidence 0.6%) reported, none of which required further intervention. Discussion: Current literature surrounding ESB in rib fracture management provides a positive qualitative evaluation of efficacy and safety. Improvements in pain and respiratory parameters were almost universal. The notable outcome from this review was the improved safety profile of ESB. The ESB was not associated with complications requiring intervention even in the setting of anticoagulation and coagulopathy. There still remains a paucity of large cohort, prospective data. Moreover, no current studies reflect an improvement in respiratory complication rates compared to current techniques. Taken together, these areas should be the focus of any future research.

10.
J Cardiothorac Surg ; 18(1): 105, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024894

RESUMO

BACKGROUND: Surgical approach is the most effective treatment for primary spontaneous pneumothorax. The two most widely adopted surgical methods are mechanical abrasion and apical pleurectomy, in addition to bullectomy. We performed a systematic review and meta-analysis to examine which technique is superior in treating primary spontaneous pneumothorax. METHODS: PubMed, MEDLINE and EMBASE databases were searched for studies published between January 2000 to September 2022 comparing mechanical abrasion and apical pleurectomy for treatment of primary spontaneous pneumothorax. The primary outcome was pneumothorax recurrence. Secondary outcomes included post-operative chest tube duration, hospital length of stay, operative time and intra-operative of blood loss. RESULTS: Eight studies were eligible for inclusion involving 1,613 patients. There was no difference in the rate of pneumothorax recurrence between pleural abrasion and pleurectomy (RR: 1.34; 95% CI: 0.94 to 1.92). However, pleural abrasion led to shorter hospital length of stay (MD: -0.25; 95% CI: -0.51 to 0.00), post-operative chest tube duration (MD: -0.30; 95% CI: -0.56 to -0.03), operative time (MD: -13.00; 95% CI -15.07 to 10.92) and less surgical blood loss (MD: -17.77; 95% CI: -24.36 to -11.18). CONCLUSION: Pleural abrasion leads to less perioperative patient burden and shorter hospital length of stay without compromising the rate of pneumothorax recurrence when compared to pleurectomy. Thus, pleural abrasion is a reasonable first choice surgical procedure for management of primary spontaneous pneumothorax.


Assuntos
Pneumotórax , Procedimentos Cirúrgicos Torácicos , Humanos , Pneumotórax/cirurgia , Pleura/cirurgia , Pleurodese/métodos , Recidiva , Procedimentos Cirúrgicos Torácicos/métodos , Resultado do Tratamento , Cirurgia Torácica Vídeoassistida/métodos
11.
Biochem Biophys Rep ; 31: 101298, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35794960

RESUMO

Acceleration of societal ageing has increased the global incidence of geriatric diseases such as Alzheimer's disease (AD), and the demands for proper diagnosis and monitoring of those diseases are also increasing daily. We utilized diffracted X-ray blinking (DXB) for amyloid ß (Aß) isoforms, which are thought to be closely related to AD, to discriminate among the dynamics of individual particles in early and long-term oligomerisation and aggregation inhibiting environments. Among the various Aß isoforms, the dynamics of Aß (1-42), which is known to be the most toxic form, were the slowest (the dynamics were lower by 78% com-pared with short-term incubation), and the dynamics were restored (the dynamics increased by 105% compared with normal aggregation) in an environment that suppressed oligomerisation of Aß (1-42). It has been confirmed that the use of DXB allows measurements of dynamics related to the functional states of the target molecules.

12.
J Neurochem ; 112(4): 870-81, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19943850

RESUMO

Declining levels of estrogen in women result in increases in gonadotropins such as luteinizing hormone (LH) through loss of feedback inhibition. LH, like estrogen, is modulated by hormone replacement therapy. However, the role of post-menopausal gonadotropin increases on cognition has not been evaluated. Here, we demonstrate that the down-regulation of ovariectomy-driven LH elevations using the gonadotropin releasing hormone super-analogue, leuprolide acetate, improves cognitive function in the Morris water maze and Y-maze tests in the absence of E2. Furthermore, our data suggest that these effects are independent of the modulation of estrogen receptors alpha and beta, or activation of CYP19 and StAR, associated with the production of endogenous E2. Importantly, pathways associated with improved cognition such as CaMKII and GluR1-Ser831 are up-regulated by leuprolide treatment but not by chronic long-term E2 replacement suggesting independent cognition-modulating properties. Our findings suggest that down-regulation of gonadotropins is as effective as E2 in modulating cognition but likely acts through different molecular mechanisms. These findings provide a potential novel protective strategy to treat menopause/age-related cognitive decline and/or prevent the development of AD.


Assuntos
Transtornos Cognitivos/terapia , Regulação para Baixo/fisiologia , Terapia de Reposição de Estrogênios/métodos , Gonadotropinas/sangue , Menopausa , Animais , Aromatase/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Gonadotropinas/genética , Leuprolida/farmacologia , Leuprolida/uso terapêutico , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia/métodos , RNA Mensageiro/metabolismo , Tempo de Reação/efeitos dos fármacos , Receptores de AMPA/metabolismo , Receptores de Estrogênio/química , Serina/genética
13.
Biophys Chem ; 242: 1-5, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30153504

RESUMO

The binding and photochirogenic behaviour of 2-anthracenecarboxylate (AC) with human serum albumin (HSA) have hitherto been investigated and comprehended as time-averaged statistical events by spectroscopic examinations and product analyses. In this study, we employed a diffracted X-ray tracking (DXT) technique to visualize the single-molecular dynamics of free and AC-loaded HSA (AC:HSA = 0, 1, 5 and 10), as well as the AC-HSA complex under photoirradiation, all of which were tethered to gold nanocrystals and hence traceable in real time by DXT. This enabled us to draw a more dynamic picture of the bio-supramolecular photochirogenesis at a single-molecule resolution, detailing the softening and flexibility enhancement of HSA upon binding of ACs to its inter-subdomain IIA-IIB site and the dynamic extrusion of AC dimers produced upon photoirradiation.


Assuntos
Antracenos/química , Ácidos Carboxílicos/química , Antracenos/metabolismo , Ácidos Carboxílicos/metabolismo , Dimerização , Ouro/química , Humanos , Lasers de Estado Sólido , Nanopartículas Metálicas/química , Ligação Proteica , Albumina Sérica/química , Albumina Sérica/metabolismo , Estereoisomerismo , Difração de Raios X
14.
Sci Rep ; 8(1): 17090, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30504916

RESUMO

Single molecule dynamics studies have begun to use quantum probes. Single particle analysis using cryo-transmission electron microscopy has dramatically improved the resolution when studying protein structures and is shifting towards molecular motion observations. X-ray free-electron lasers are also being explored as routes for determining single molecule structures of biological entities. Here, we propose a new X-ray single molecule technology that allows observation of molecular internal motion over long time scales, ranging from milliseconds up to 103 seconds. Our method uses both low-dose monochromatic X-rays and nanocrystal labelling technology. During monochromatic X-ray diffraction experiments, the intensity of X-ray diffraction from moving single nanocrystals appears to blink because of Brownian motion in aqueous solutions. X-ray diffraction spots from moving nanocrystals were observed to cycle in and out of the Bragg condition. Consequently, the internal motions of a protein molecule labelled with nanocrystals could be extracted from the time trajectory using this diffracted X-ray blinking (DXB) approach. Finally, we succeeded in distinguishing the degree of fluctuation motions of an individual acetylcholine-binding protein (AChBP) interacting with acetylcholine (ACh) using a laboratory X-ray source.


Assuntos
Movimento (Física) , Proteínas/química , Difração de Raios X/métodos , Acetilcolina/química , Microscopia Crioeletrônica/métodos , Microscopia Eletrônica de Transmissão/métodos
15.
J Hazard Mater ; 293: 30-6, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25819991

RESUMO

A new material was developed and evaluated for the targeted removal of trichlorophenol (TCP) from among potential interferents which are known to degrade removal activity. To achieve TCP-targeted activity, an alginate bead containing nanoscale palladium/zero-valent iron (Pd/nZVI) was coated with a highly hydrophobic oleic acid layer. The new material (Pd/nZVI-A-O) preferentially sorbed TCP from a mixture of chlorinated phenols into the oleic acid cover layer and subsequently dechlorinated it to phenol. The removal efficacy of TCP by Pd/nZVI-A-O was not affected by co-existing organic substances such as Suwannee River humic acid (SRHA), whereas the material without the oleic acid layer (Pd/nZVI-A) became less effective with increasing SRHA concentration. The inorganic substances nitrate and phosphate significantly reduced the reactivity of Pd/nZVI-A, however, Pd/nZVI-A-O showed similar TCP removal efficacies regardless of the initial inorganic ion concentrations. The influence of bicarbonate on the TCP removal efficacies of both Pd/nZVI-A and Pd/nZVI-A-O was not significant. The findings from this study suggest that Pd/nZVI-A-O, with its targeted, constant reactivity for TCP, would be effective for treating this contaminant in surface water or groundwater containing various competitive substrates.


Assuntos
Alginatos/química , Clorofenóis/química , Ferro/química , Ácido Oleico/química , Paládio/química , Poluentes Químicos da Água/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Purificação da Água
16.
Rev Sci Instrum ; 84(10): 103701, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24182113

RESUMO

Diffracted X-ray tracking (DXT) enables the tilting and twisting motions of single protein molecules to be monitored with micro- to milliradian resolution using a highly brilliant X-ray source with a wide energy bandwidth. We have developed a technique to monitor single molecules using gold nanocrystals attached to individual protein molecules using the BL28B2 beamline at SPring-8. In this paper we present the installation of a single toroidal X-ray mirror at BL28B2 to focus X-rays in an energy range of 10-20 keV (ΔE/E = 82% for an X-ray with a wide energy bandwidth). With this beamline we tracked diffraction spots from gold nanocrystals over a wide angle range than that using quasi-monochromatic X-rays. Application of the wide angle DXT technique to biological systems enabled us to observe the on-site motions of single protein molecules that have been functionalized in vivo. We further extend the capability of DXT by observing the fractional tilting and twisting motions of inner proteins under various conditions. As a proof of this methodology and to determine instrumental performance the intramolecular motions of a human serum albumin complex with 2-anthracenecarboxylic acid was investigated using the BL28B2 beamline. The random tilting and twisting intramolecular motions are shown to be directly linked to the movement of individual protein molecules in the buffer solution.


Assuntos
Movimento , Albumina Sérica/metabolismo , Difração de Raios X/métodos , Antracenos/metabolismo , Ácidos Carboxílicos/metabolismo , Humanos , Difração de Raios X/instrumentação
17.
Neurobiol Aging ; 33(9): 2062-71, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21982274

RESUMO

Recent studies have implicated resveratrol and pterostilbene, a resveratrol derivative, in the protection against age-related diseases including Alzheimer's disease (AD). However, the mechanism for the favorable effects of resveratrol in the brain remains unclear and information about direct cross-comparisons between these analogs is rare. As such, the purpose of this study was to compare the effectiveness of diet-achievable supplementation of resveratrol to that of pterostilbene at improving functional deficits and AD pathology in the SAMP8 mouse, a model of accelerated aging that is increasingly being validated as a model of sporadic and age-related AD. Furthermore we sought to determine the mechanism of action responsible for functional improvements observed by studying cellular stress, inflammation, and pathology markers known to be altered in AD. Two months of pterostilbene diet but not resveratrol significantly improved radial arm water maze function in SAMP8 compared with control-fed animals. Neither resveratrol nor pterostilbene increased sirtuin 1 (SIRT1) expression or downstream markers of sirtuin 1 activation. Importantly, markers of cellular stress, inflammation, and AD pathology were positively modulated by pterostilbene but not resveratrol and were associated with upregulation of peroxisome proliferator-activated receptor (PPAR) alpha expression. Taken together our findings indicate that at equivalent and diet-achievable doses pterostilbene is a more potent modulator of cognition and cellular stress than resveratrol, likely driven by increased peroxisome proliferator-activated receptor alpha expression and increased lipophilicity due to substitution of hydroxy with methoxy group in pterostilbene.


Assuntos
Envelhecimento/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Neurotransmissores/administração & dosagem , Estilbenos/administração & dosagem , Envelhecimento/sangue , Envelhecimento/genética , Doença de Alzheimer/genética , Análise de Variância , Animais , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica/efeitos dos fármacos , MAP Quinase Quinase 4/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Neurotransmissores/sangue , PPAR alfa/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Estilbenos/sangue , Proteínas tau/metabolismo , Quinase Induzida por NF-kappaB
18.
Clin Exp Otorhinolaryngol ; 2(4): 211-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20072698

RESUMO

The combined effects of inhaled irritant gases and heat in burn patients can result in the development of laryngotracheal strictures. Several factors could adversely affect the development of tracheal stenosis and cause the growth of granulation tissue. Yet the current treatment options for this condition are limited because of the paucity of case reports. We report here on a case of a patient who experienced recurrent upper tracheal stenosis after an inhalation injury. She displayed repetitive symptoms of stenosis even after several laryngomicrosurgeries and resection with end-to-end anastomosis. Finally, 5 yr after the burn injury, slide tracheoplasty was successfully performed and the postoperative check-up findings and the increased airway volume seen on imaging were all satisfactory.

19.
J Org Chem ; 68(1): 43-9, 2003 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-12515459

RESUMO

Enantiomerically pure N-(R)-alpha-methylbenzyl-4(R)-(chloromethyl)oxazolidinones (4R)-5a-k were synthesized in one step and high yields from various aziridine-2-methanols (S)-2a-k by intramolecular cyclization with phosgene. The alpha-methylbenzyl substituent on the nitrogen was easily cleaved to give both enanatiomers of 4-(chloromethyl)oxazolidinones (R)-7a and (S)-7a. (R)-7a was used for the efficient syntheses of (L)-homophenylalaninol analogues (S)-12a-j. We also applied the same methodology to prepare oxazolidinones 9a-c containing a heteroatom-substituted alkyl group at C-4 in high yields.

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