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1.
Phys Chem Chem Phys ; 25(32): 21562-21572, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37545426

RESUMO

We present the relaxation dynamics of deuterated water molecules via autoionization, initiated by the absorption of a 61 eV photon, producing the very rare D+ + O+ + D breakup channel. We employ the COLd target recoil ion momentum spectroscopy method to measure the 3D momenta of the ionic fragments and emitted electrons from the dissociating molecule in coincidence. We interpret the results using the potential energy surfaces extracted from multi-reference configuration interaction calculations. The measured particle energy distributions can be related to a super-excited monocationic state located above the double ionization threshold of D2O. The autoionized electron energy shows a sharp distribution centered around 0.5 eV, which is a signature of the atomic oxygen autoionization occurring in the direct and sequential dissociation processes of D2O+* at a large internuclear distance. In this way, an O+ radical fragment and a low-energy electron are created, both of which can trigger secondary reactions in their environment.

2.
J Chem Phys ; 159(9)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37668253

RESUMO

We present an investigation of the relaxation dynamics of deuterated water molecules after direct photo-double ionization at 61 eV. We focus on the very rare D+ + O+ + D reaction channel in which the sequential fragmentation mechanisms were found to dominate the dynamics. Aided by theory, the state-selective formation and breakup of the transient OD+(a1Δ, b1Σ+) is traced, and the most likely dissociation path-OD+: a1Δ or b1Σ+ → A 3Π â†’ X 3Σ- → B 3Σ--involving a combination of spin-orbit and non-adiabatic charge transfer transitions is determined. The multi-step transition probability of this complex transition sequence in the intermediate fragment ion is directly evaluated as a function of the energy of the transient OD+ above its lowest dissociation limit from the measured ratio of the D+ + O+ + D and competing D+ + D+ + O sequential fragmentation channels, which are measured simultaneously. Our coupled-channel time-dependent dynamics calculations reproduce the general trends of these multi-state relative transition rates toward the three-body fragmentation channels.

3.
Br J Surg ; 107(13): 1741-1750, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32926410

RESUMO

BACKGROUND: The efficacy of negative pressure wound therapy (NPWT) in the acute management of burns remains unclear. The purpose of this trial was to compare standard Acticoat™ and Mepitel™ dressings with combined Acticoat™, Mepitel™ and continuous NPWT to determine the effect of adjunctive NPWT on re-epithelialization in paediatric burns. METHODS: This two-arm, single-centre RCT recruited children with acute thermal burns covering less than 5 per cent of their total body surface area. The primary outcome was time to re-epithelialization. Blinded assessments were performed using photographs captured every 3-5 days until discharge. Secondary measures included pain, itch, grafting, perfusion and scar management referrals. RESULTS: Some 114 patients were randomized. Median time to re-epithelialization was 8 (i.q.r. 7-11) days in the NPWT group and 10 (8-14) days in the control group. In a multivariable model, NPWT decreased the expected time to wound closure by 22 (95 per cent c.i. 7 to 34) per cent (P = 0·005). The risk of referral to scar management was reduced by 60 (18 to 81) per cent (P = 0·013). Four participants in the control group and one in the NPWT group underwent grafting. There were no statistically significant differences between groups in pain, itch or laser Doppler measures of perfusion. Adverse events were rare and minor, although NPWT carried a moderate treatment burden, with ten patients discontinuing early. CONCLUSION: Adjunctive NPWT hastened re-epithelialization in small-area burn injuries in children, but had a greater treatment burden than standard dressings alone. Registration number: ACTRN12618000256279 ( http://ANZCTR.org.au).


ANTECEDENTES: La eficacia del tratamiento de las heridas con presión negativa (negative pressure wound therapy, NPWT) en el tratamiento agudo de las quemaduras sigue sin estar claro. El propósito de este ensayo clínico fue comparar los apósitos estándar del tipo Acticoat™ y Mepitel™ con la combinación de Acticoat™, Mepitel™ y NPWT continua para determinar el efecto de la adición de NPWT en la reepitelización de las quemaduras en pediatría. MÉTODOS: Ensayo controlado y aleatorizado, con dos brazos y unicéntrico, que reclutó niños con quemaduras térmicas agudas que afectaban < 5% de la superficie corporal total. El resultado primario fue el tiempo hasta la reepitelización. Se realizaron evaluaciones a ciegas utilizando fotografías tomadas cada 3-5 días hasta el alta hospitalaria. Las medidas secundarias incluían dolor, picor, injerto, perfusión y derivación para el tratamiento de las cicatrices. RESULTADOS: Se aleatorizaron un total de 114 pacientes. La mediana de tiempo hasta la reepitelización fue 8 días (rango intercuartílico, interquartile range, IQR 7-11) en el grupo NPWT y 10 días (8-14) en el grupo control. En el modelo multivariable, el uso de NPWT disminuyó los días previstos hasta el cierre de la herida en un 22% (i.c. del 95% 7-34%; P = 0,005). El riesgo de ser derivado para el tratamiento de la cicatriz se redujo en un 60% (18-81%; P = 0,013). Cuatro participantes en el grupo control y uno en el grupo NPWT fueron sometidos a injertos. No hubo diferencias estadísticamente significativas en el dolor, picor, o mediciones de la perfusión con Doppler laser. Los eventos adversos fueron raros y menores, aunque NPWT conllevó una carga de tratamiento moderada con 10 pacientes que lo suspendieron precozmente. CONCLUSIÓN: El tratamiento complementario de la herida con presión negativa acelera el tiempo hasta la reepitelización en quemaduras de pequeña extensión en niños, pero implica una mayor carga de tratamiento.


Assuntos
Queimaduras/terapia , Tratamento de Ferimentos com Pressão Negativa , Curativos Oclusivos , Poliésteres/uso terapêutico , Polietilenos/uso terapêutico , Silicones/uso terapêutico , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Modelos de Riscos Proporcionais , Reepitelização , Método Simples-Cego , Resultado do Tratamento , Cicatrização
4.
BMC Public Health ; 20(1): 284, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131784

RESUMO

BACKGROUND: Paediatric burns are highly painful and traumatising injuries that are overrepresented among Aboriginal and Torres Strait Islander people. Paediatric burn patients' pain remains poorly managed by pharmacological interventions, leading to increased anxiety, distress, and trauma in patients and their caregivers. Non-pharmacological psychosocial interventions have been suggested as effective in reducing pain and psychological morbidities among paediatric burn patients and their caregivers; however, their degree of effectiveness and appropriateness for Aboriginal and Torres Strait Islander people is unclear. METHODS: A non-date restricted systematic review was conducted through four databases. Studies published in English assessing psychosocial interventions on paediatric burn patients' physical pain along with theirs and/or their caregiver's anxiety, distress, or trauma symptoms were identified and included in this review. Included studies were assessed for their ability to reduce one of the outcomes of interests and for their reflection of Aboriginal and Torres Strait Islander peoples' perspectives of health. RESULTS: Of the 3178 identified references, 17 were eligible. These include distraction based techniques (n = 8), hypnosis/familiar imagery (n = 2), therapeutic approaches (n = 4), and patient preparation/procedural control (n = 3). Distraction techniques incorporating procedural preparation reduced pain, while discharge preparation and increased 'patient control' reduced patient and caregiver anxiety; and internet based Cognitive Behaviour Therapy reduced short-term but not long-term post-traumatic stress symptoms. No interventions reflected Aboriginal and Torres Strait Islander peoples' perspectives of health; and few targeted caregivers or focused on reducing their symptoms. CONCLUSIONS: The development and assessment of psychosocial interventions to appropriately meet the needs of Aboriginal and Torres Strait Islander paediatric burn patients is required.


Assuntos
Queimaduras/psicologia , Queimaduras/terapia , Cuidadores/psicologia , Psicoterapia , Criança , Competência Cultural , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
Eur J Clin Pharmacol ; 75(1): 1-11, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30187103

RESUMO

Competition arising from the increasing availability of biosimilar medicines has resulted in healthcare savings and has provided greater patient access to high cost therapeutics in Europe. The biosimilar market in the USA is relatively new so the full impact of biosimilar availability remains to be seen. Educational initiatives relating to the use of biosimilar medicines are currently being undertaken by regulators, policy makers and industry. The debate on biosimilars has moved on from the appropriateness of the regulatory framework which governs their approval, to the practice of interchangeability. Interchangeability is an important issue for healthcare professionals but different definitions and regulatory frameworks exist in the USA and Europe. In the USA, an interchangeable biological product is a biosimilar which may be substituted by a pharmacist, subject to local State policies. The interchangeability of a biosimilar with its reference medicine will be evaluated by the United States Food and Drug Administration (FDA) in cases where approval as an 'interchangeable product' is sought. In contrast, the European Medicines Agency (EMA) does not assess or make recommendations on interchangeability, therefore, in Europe, interchangeability does not mean substitution but is generally physician-led or driven by national policy. This paper provides an overview of the regulation of biosimilar medicines. Challenges associated with the demonstration of interchangeability and practical considerations relating to switching are also discussed. Finally, we present policies that have been adopted to date in several European countries, the USA and Australia, which aim to promote the use of biosimilar medicines.


Assuntos
Produtos Biológicos/normas , Medicamentos Biossimilares/normas , Aprovação de Drogas/legislação & jurisprudência , Animais , Austrália , Produtos Biológicos/administração & dosagem , Medicamentos Biossimilares/administração & dosagem , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Europa (Continente) , Humanos , Estados Unidos , United States Food and Drug Administration
6.
Nutr Metab Cardiovasc Dis ; 28(12): 1296-1303, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30459055

RESUMO

BACKGROUND & AIMS: Serum lipids and lipoproteins are established biomarkers of cardiovascular disease risk that could be influenced by impaired gut barrier function via effects on the absorption of dietary and biliary cholesterol. The aim of this study was to examine the potential relationship between gut barrier function (gut permeability) and concentration of serum lipids and lipoproteins, in an ancillary analysis of serum samples taken from a previous study. METHODS AND RESULTS: Serum lipids, lipoproteins and functional gut permeability, as assessed by the percentage of the urinary recovery of 51Cr-labelled EDTA absorbed within 24 h, were measured in a group of 30 healthy men. Serum lipopolysaccharide, high sensitivity C-reactive protein and interleukin-6 were also measured as markers of low-grade inflammation. The group expressed a 5-fold variation in total gut permeability (1.11-5.03%). Gut permeability was unrelated to the concentration of both serum total and low density lipoprotein (LDL)-cholesterol, but was positively associated with serum high density lipoprotein (HDL)-cholesterol (r = 0.434, P = 0.015). Serum HDL-cholesterol was also positively associated with serum endotoxaemia (r = 0.415, P = 0.023). CONCLUSION: The significant association between increased gut permeability and elevated serum HDL-cholesterol is consistent with the role of HDL as an acute phase reactant, and in this situation, potentially dysfunctional lipoprotein. This finding may have negative implications for the putative role of HDL as a cardio-protective lipoprotein.


Assuntos
HDL-Colesterol/sangue , Dislipidemias/sangue , Mediadores da Inflamação/sangue , Inflamação/sangue , Absorção Intestinal , Intestinos/fisiopatologia , Adulto , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos Transversais , Dislipidemias/diagnóstico , Dislipidemias/fisiopatologia , Humanos , Inflamação/diagnóstico , Inflamação/fisiopatologia , Interleucina-6/sangue , Lipopolissacarídeos/sangue , Masculino , Pessoa de Meia-Idade , Permeabilidade , Regulação para Cima
7.
Microcirculation ; 24(5)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28182312

RESUMO

Microfluidic systems have emerged as a new class of perfusable in vitro culture models that have helped advance and refine our understanding of microvascular function. Cutting-edge microfluidic models have successfully integrated principles from quantitative analysis of vascular function, in vitro flow chambers, microfabrication techniques, and 3D tissue scaffolds. Here, we review the evolution of microfluidic systems, namely their progression from 2D planar microchannel arrays to 3D microtissue analogs, and highlight their recent contributions in elucidating the role of biomolecular transport and fluid mechanical stimuli in controlling angiogenesis. Further advancement of microfluidic systems in recapitulating tissue-level phenomena in vitro, controlling important physiochemical and biological parameters, and integrating cellular and molecular analysis will help further enhance their application within the microcirculation research community.


Assuntos
Microcirculação , Microfluídica/métodos , Neovascularização Fisiológica , Humanos , Pesquisa/tendências , Técnicas de Cultura de Tecidos
8.
Opt Lett ; 39(21): 6162-5, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25361304

RESUMO

We demonstrate the first reflection-based epi-illumination diffraction phase microscope with white light (epi-wDPM). The epi-wDPM system combines the off-axis, common-path, and white light approaches, in a reflection geometry enabling sub-nanometer spatial and temporal noise levels, while providing single-shot acquisition for opaque samples. We verified the epi-wDPM results by measuring control samples with known dimensions and comparing them to measurements from other well-established techniques. We imaged gold-coated HeLa cells to illustrate the tradeoffs between epi-wDPM with low and high spatial coherence.

9.
Diabet Med ; 31(11): 1310-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25047698

RESUMO

AIMS: To investigate the relationship between adiposity and plasma free fatty acid levels and the influence of total plasma free fatty acid level on insulin sensitivity and ß-cell function. METHODS: An insulin sensitivity index, acute insulin response to glucose and a disposition index, derived from i.v. glucose tolerance minimal model analysis and total fasting plasma free fatty acid levels were available for 533 participants in the Reading, Imperial, Surrey, Cambridge, Kings study. Bivariate correlations were made between insulin sensitivity index, acute insulin response to glucose and disposition index and both adiposity measures (BMI, waist circumference and body fat mass) and total plasma free fatty acid levels. Multivariate linear regression analysis was performed, controlling for age, sex, ethnicity and adiposity. RESULTS: After adjustment, all adiposity measures were inversely associated with insulin sensitivity index (BMI: ß = -0.357; waist circumference: ß = -0.380; body fat mass: ß = -0.375) and disposition index (BMI: ß = -0.215; waist circumference: ß = -0.248; body fat mass: ß = -0.221) and positively associated with acute insulin response to glucose [BMI: ß = 0.200; waist circumference: ß = 0.195; body fat mass ß = 0.209 (P values <0.001)]. Adiposity explained 13, 4 and 5% of the variation in insulin sensitivity index, acute insulin response to glucose and disposition index, respectively. After adjustment, no adiposity measure was associated with free fatty acid level, but total plasma free fatty acid level was inversely associated with insulin sensitivity index (ß = -0.133), acute insulin response to glucose (ß = -0.148) and disposition index [ß = -0.218 (P values <0.01)]. Plasma free fatty acid concentration accounted for 1.5, 2 and 4% of the variation in insulin sensitivity index, acute insulin response to glucose and disposition index, respectively. CONCLUSIONS: Plasma free fatty acid levels have a modest negative association with insulin sensitivity, ß-cell secretion and disposition index but no association with adiposity measures. It is unlikely that plasma free fatty acids are the primary mediators of obesity-related insulin resistance or ß-cell dysfunction.


Assuntos
Adiposidade , Diabetes Mellitus Tipo 2/etiologia , Ácidos Graxos não Esterificados/sangue , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Obesidade/sangue , Adulto , Idoso , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Inglaterra/epidemiologia , Feminino , Humanos , Secreção de Insulina , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Fatores de Risco , Circunferência da Cintura
10.
J Clin Imaging Sci ; 14: 15, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841313

RESUMO

Knee pathology, including anterior cruciate ligament (ACL) tears, meniscal tears, articular cartilage lesions, and intra-articular masses or cysts are common clinical entities treated by orthopedic surgeons with arthroscopic surgery. Preoperatively, magnetic resonance imaging (MRI) is now standard in confirming knee pathology, particularly detecting pathology less evident with history and physical examination alone. The radiologist's MRI interpretation becomes essential in evaluating intra-articular knee structures. Typically, the radiologist that interprets the MRI does not have the opportunity to view the same pathology arthroscopically. Thus, the purpose of this article is to illustratively reconcile what the orthopedic surgeon sees arthroscopically with what the radiologist sees on magnetic resonance imaging when viewing the same pathology. Correlating virtual and actual images can help better understand pathology, resulting in more accurate MRI interpretations. In this article, we present and review a series of MR and correlating arthroscopic images of ACL tears, meniscal tears, chondral lesions, and intra-articular masses and cysts. Short teaching points are included to highlight the importance of radiological signs and pathological MRI appearance with significant clinical and arthroscopic findings.

11.
Int J Obes (Lond) ; 37(2): 216-23, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22410962

RESUMO

INTRODUCTION AND OBJECTIVES: An obese-type human microbiota with an increased Firmicutes:Bacteroidetes ratio has been described that may link the gut microbiome with obesity and metabolic syndrome (MetS) development. Dietary fat and carbohydrate are modifiable risk factors that may impact on MetS by altering the human microbiome composition. We determined the effect of the amount and type of dietary fat and carbohydrate on faecal bacteria and short chain fatty acid (SCFA) concentrations in people 'at risk' of MetS. DESIGN: A total of 88 subjects at increased MetS risk were fed a high saturated fat diet (HS) for 4 weeks (baseline), then randomised onto one of the five experimental diets for 24 weeks: HS; high monounsaturated fat (MUFA)/high glycemic index (GI) (HM/HGI); high MUFA/low GI (HM/LGI); high carbohydrate (CHO)/high GI (HC/HGI); and high CHO/low GI (HC/LGI). Dietary intakes, MetS biomarkers, faecal bacteriology and SCFA concentrations were monitored. RESULTS: High MUFA diets did not affect individual bacterial population numbers but reduced total bacteria and plasma total and LDL-cholesterol. The low fat, HC diets increased faecal Bifidobacterium (P=0.005, for HC/HGI; P=0.052, for HC/LGI) and reduced fasting glucose and cholesterol compared to baseline. HC/HGI also increased faecal Bacteroides (P=0.038), whereas HC/LGI and HS increased Faecalibacterium prausnitzii (P=0.022 for HC/HGI and P=0.018, for HS). Importantly, changes in faecal Bacteroides numbers correlated inversely with body weight (r=-0.64). A total bacteria reduction was observed for high fat diets HM/HGI and HM/LGI (P=0.023 and P=0.005, respectively) and HS increased faecal SCFA concentrations (P<0.01). CONCLUSION: This study provides new evidence from a large-scale dietary intervention study that HC diets, irrespective of GI, can modulate human faecal saccharolytic bacteria, including bacteroides and bifidobacteria. Conversely, high fat diets reduced bacterial numbers, and in the HS diet, increased excretion of SCFA, which may suggest a compensatory mechanism to eliminate excess dietary energy.


Assuntos
Colo/microbiologia , Carboidratos da Dieta , Gorduras na Dieta , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Síndrome Metabólica/microbiologia , Obesidade/microbiologia , Adulto , Idoso , Bacteroides/isolamento & purificação , Bifidobacterium/isolamento & purificação , Glicemia/metabolismo , Colesterol/sangue , Cromatografia Gasosa , Colo/metabolismo , Dieta , Ácidos Graxos Monoinsaturados/metabolismo , Feminino , Fermentação , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/metabolismo , Medição de Risco , Reino Unido/epidemiologia , Populações Vulneráveis
12.
Lupus ; 22(12): 1267-73, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24097999

RESUMO

Lupus nephritis needs to be diagnosed promptly and treated specifically with appropriate immunosuppression. However, all patients with lupus nephritis have by definition chronic kidney disease (CKD) as they will have proteinuria with varying degrees of renal impairment. CKD requires careful additional management, not only to reduce the risk of progression to end-stage renal disease but also because it is probably the strongest risk for cardiovascular morbidity and mortality. This review focuses on the evidence underscoring strategies to prevent progression of CKD beyond the "simple" treatment of the lupus nephritis. The strategies include immaculate control of blood pressure, inhibition of the renin-angiotensin system to reduce blood pressure and proteinuria, and the benefits of lifestyle modifications such as tackling smoking, obesity and exercise. We also review the literature on control of dyslipidaemias which, although clearly of cardiovascular benefit, provide less compelling data for offering renoprotection. We touch on the emerging area of the importance of controlling urate levels in protecting against progressive renal impairment. Finally, there is a reminder about the importance of considering the nephrotoxicity of all medications prescribed for patients with lupus nephritis - above all the need to avoid the use of non-steroidal anti-inflammatory drugs. Overall, the theme is that there is much more to the management of patients with lupus nephritis than "just" the nephritis - a multidisciplinary approach involving nephrologists as well as rheumatologists is more likely to provide the appropriate wider care required for all patients with lupus nephritis.


Assuntos
Falência Renal Crônica/prevenção & controle , Nefrite Lúpica/terapia , Insuficiência Renal Crônica/terapia , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Pressão Sanguínea , Progressão da Doença , Dislipidemias/complicações , Dislipidemias/terapia , Humanos , Terapia de Imunossupressão/métodos , Falência Renal Crônica/etiologia , Falência Renal Crônica/fisiopatologia , Estilo de Vida , Nefrite Lúpica/complicações , Nefrite Lúpica/diagnóstico , Proteinúria/etiologia , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Ácido Úrico/metabolismo
13.
Intern Med J ; 43(8): 927-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23611119

RESUMO

BACKGROUND: Undertaking commercial coaching to improve one's chance of selection into medical school is widespread. Although its effect on selection test performance appears to be relatively minimal, its impact on the predictive validity of the tests is unknown. AIMS: To examine whether commercial coaching for the Undergraduate Medical and Health Sciences Admissions Test (UMAT) changes its ability to predict the subsequent academic performance of medical students. METHODS: The first two cohorts to enrol in a new Australian medical school provided information at the time of their selection interview about whether or not they had undertaken a commercial coaching course to help prepare for the UMAT. Final academic grades for each year of the degree and overall grade point average (GPA) of coached students were compared with those of non-coached students. Moderated regression analyses examined differences in the relationship between UMAT scores and examination results while controlling for entry UMAT scores and past academic performance. RESULTS: Coached students had a lower GPA than those who were not coached. In cohort 1, coached students performed more poorly than non-coached students in every year of their degree. This effect, while similar, was not statistically significant in cohort 2. CONCLUSIONS: Differences in selection process and learning context between the two cohorts may explain why coaching was only significantly related to the performance of one cohort. Further research is required to ascertain if coached students develop a learning style that hinders ongoing acquisition of knowledge, which might have serious implications for job performance after graduation.


Assuntos
Avaliação Educacional/normas , Critérios de Admissão Escolar , Faculdades de Medicina/normas , Estudantes de Medicina , Estudos de Coortes , Avaliação Educacional/métodos , Feminino , Humanos , Masculino , Critérios de Admissão Escolar/tendências , Faculdades de Medicina/tendências , Inquéritos e Questionários
14.
Biomater Adv ; 145: 213263, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36623354

RESUMO

Photodynamic therapy (PDT) efficiency is directly affected by the reactive oxygen species (ROS) generated by photosensitizers. However, ROSs' ultrashort life span and limited diffusion distance restrict the PDT efficiency. Therefore, it is important to control the delivery strategy of photosensitizers for PDT treatment. Herein, the core-satellite nanoreactors were fabricated with oxygen generation and ROS diffusion properties. The hollow CuS encapsulating horseradish peroxidase (HRP) was combined with the cationic photosensitizers (PEI-Ce6). The unique photosensitizers delivery strategy makes the nanoreactors achieve ROS diffusion-enhanced PDT effect. First, HRP in "core" (HRP@CuS) can decompose hydrogen peroxide (H2O2) to O2, increasing O2 levels on the surface of the nanoreactor. Second, the Ce6 molecules covalent-linked with PEI are uniformly dispersed on the surface of CuS as a "satellite", avoiding Ce6 aggregation and causing more Ce6 molecules be activated to produce more 1O2. Due to the Ce6 was on the surface of the CuS nanocages, the generated ROS may ensure a larger diffusion range. Meanwhile, the inherently CuS nanocages exhibit photothermal and photoacoustic (PA) effect. The photothermal effect further enhances the ROS diffusion. Under the guidance of PA imaging, nanoreactors exhibit highly efficient hypoxic tumor ablation via photodynamic and photothermal effect. Overall, the core-satellite nanoreactors provide an effective strategy for tumor therapy, further promoting the research of photosensitizers delivery.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Linhagem Celular Tumoral , Fototerapia/métodos , Oxigênio , Hipóxia/tratamento farmacológico , Nanotecnologia
15.
Adv Health Sci Educ Theory Pract ; 17(3): 377-88, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21751103

RESUMO

Given the accumulating evidence that performance in medical school and beyond is related to personality, it is important for research to consider how personality assessment can be included as part of the process of selecting medical students. Interviews are one way of measuring personality and this study extends prior research investigating whether the multiple mini interview (MMI) is related to the five factor model of personality. In contrast to prior results (Kulasegaram et al. in Adv Health Sci Edu 15:415-423, 2010), examination of MMI scores for 868 applicants to an Australian medical school over 3 years showed significant uncorrected correlations every year with extraversion (.19, .19, .30) and conscientiousness (.20, .22, .25) and with agreeableness in 2 years (.17, .19). Investigation of personality at a facet-level revealed differing relationships with the MMI within the five factors of personality. MMI scores were also correlated in 2 years (.17, .22) with a situational judgment test of interpersonal understanding (UMAT Section 2) but were unrelated to tests of logical reasoning ability (UMAT Section 1), non-verbal reasoning (Section 3), or past academic performance (Higher School Certificate results).


Assuntos
Associação , Determinação da Personalidade , Testes de Personalidade , Austrália , Humanos , Determinação da Personalidade/estatística & dados numéricos , Pesquisa Qualitativa , Critérios de Admissão Escolar , Faculdades de Medicina
16.
Public Health ; 126(10): 827-35, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23083844

RESUMO

OBJECTIVES: Test the association between coronary heart disease (CHD) risk scores and neighborhood socioeconomic status (NSES) in a US nationally-representative sample and describe whether the association varies by gender and race/ethnicity. STUDY DESIGN: Cross-sectional study. METHODS: We use Health and Nutrition Examination Survey (NHANES) data from 1999 to 2004 linked with Census tract data. Multivariable regression models and propensity score adjusted models are employed to test the association between NSES and 10-year risk of CHD based on the Framingham Risk Score (FRS), adjusting for individual-level characteristics. RESULTS: An individual living in a neighborhood at the 75th percentile of NSES (high NSES) has, on average, a 10-year CHD risk that is 0.16 percentage points lower (95% Confidence Interval 0.16, 0.17) than a similar person residing in a neighborhood at the 25th percentile of NSES (low NSES). Race/ethnicity and gender were found to significantly modify the association between NSES and CHD risk: the association is larger in men than women and in whites than minorities. Propensity score models showed that findings on the main effects of NSES were robust to self-selection into neighborhoods. Similar results were observed between NSES and risk of cardiovascular disease events. CONCLUSIONS: NSES is significantly associated with CHD risk, and the relationship varies by gender and race/ethnicity.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Doença das Coronárias/etnologia , Hispânico ou Latino/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , População Branca/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fatores de Risco , Distribuição por Sexo , Fatores Socioeconômicos , Estados Unidos/epidemiologia
17.
Biomater Biosyst ; 32021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35317095

RESUMO

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid mediator of endothelial barrier function. Prior studies have implicated mechanical stimulation due to intravascular laminar shear stress in co-regulating S1P signaling in endothelial cells (ECs). Yet, vascular networks in vivo consist of vessel bifurcations, and this geometry generates hemodynamic forces at the bifurcation point distinct from laminar shear stress. However, the role of these forces at vessel bifurcations in regulating S1P-dependent endothelial barrier function is not known. In this study, we implemented a microfluidic platform that recapitulates the flow dynamics of vessel bifurcations with in situ quantification of the permeability of microvessel analogues. Co-application of S1P with impinging bifurcated fluid flow, which is characterized by approximately zero shear stress and 38 dyn•cm-2 stagnation pressure at the vessel bifurcation point, promotes vessel stabilization. Similarly, co-treatment of S1P with 3 dyn•cm-2 laminar shear stress is also protective of endothelial barrier function. Moreover, it is shown that vessel stabilization due to bifurcated fluid flow and laminar shear stress is dependent on S1P receptor 1 or 2 signaling. Collectively, these findings demonstrate the endothelium-protective function of fluid forces at vessel bifurcations and their involvement in coordinating S1P-dependent regulation of vessel permeability.

18.
Br J Cancer ; 103(2): 265-74, 2010 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-20551953

RESUMO

BACKGROUND: The mitogen-activated protein kinase (MAPK) phosphatases or dual specificity phosphatases (DUSPs) are a family of proteins that catalyse the inactivation of MAPK in eukaryotic cells. Little is known of the expression, regulation or function of the DUSPs in human neoplasia. METHODS: We used RT-PCR and quantitative PCR (qPCR) to examine the expression of DUSP16 mRNA. The methylation in the DUSP16 CpG island was analysed using bisulphite sequencing and methylation-specific PCR. The activation of MAPK was determined using western blotting with phospho-specific antibodies for extra-cellular signal-related kinase (ERK), p38 and c-Jun N-terminal kinase (JNK). The proliferation of cell lines was assessed using the CellTiter 96 Aqueous One assay. RESULTS: The expression of DUSP16, which inactivates MAPK, is subject to methylation-dependent transcriptional silencing in Burkitt's Lymphoma (BL) cell lines and in primary BL. The silencing is associated with aberrant methylation in the CpG island in the 5' regulatory sequences of the gene blocking its constitutive expression. In contrast to BL, the CpG island of DUSP16 is unmethylated in other non-Hodgkin's lymphomas (NHLs) and epithelial malignancies. In BL cell lines, neither constitutive nor inducible ERK or p38 activity varied significantly with DUSP16 status. However, activation of JNK was increased in lines with DUSP16 methylation. Furthermore, methylation in the DUSP16 CpG island blocked transcriptional induction of DUSP16, thereby abrogating a normal physiological negative feedback loop that limits JNK activity, and conferred increased cellular sensitivity to agents, such as sorbitol and anthracycline chemotherapeutic agents that activate JNK. CONCLUSION: DUSP16 is a new epigenetically regulated determinant of JNK activation in BL.


Assuntos
Linfoma de Burkitt/genética , Fosfatases de Especificidade Dupla/genética , Fosfatases da Proteína Quinase Ativada por Mitógeno/genética , Linhagem Celular Tumoral , Metilação de DNA , Fosfatases de Especificidade Dupla/metabolismo , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Transdução de Sinais
19.
Cell Mol Biol (Noisy-le-grand) ; 56(1): 52-8, 2010 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-20196970

RESUMO

OBJECTIVE: Dietary guidelines for the prevention of coronary heart disease (CHD) have restricted the intake of foods rich in dietary cholesterol, on the grounds that the dietary cholesterol will increase blood cholesterol. In the case of shellfish, this recommendation may limit the intake of a valuable dietary source of long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA). The objective of this study was to undertake a dietary intervention to determine the effects of cold water prawns on plasma lipids and lipoproteins. METHODS: 23 healthy male subjects were randomised to receive either 225 g of cold water prawns or an equivalent weight of fish ('crab') sticks as a control for 12 weeks in a cross-over design. Blood samples were taken at the beginning and end of each intervention for the determination of plasma lipids and lipoproteins by routine enzymatic assays and iodixanol density gradient centrifugation respectively. RESULTS: The diets were well matched for the intake of total energy and macronutrients, and body weight remained stable throughout the study. The prawn intervention increased the intake of dietary cholesterol to 750 mg/d against 200 mg/d on the control. The intake of LC n-3 PUFA from prawns was estimated to be between 0.5-0.7 g/d. The consumption of prawns produced no significant effects on the concentration of plasma total or LDL cholesterol, triacylglycerol, HDL cholesterol or apolipoproteins A-I and B relative to the control, or within each intervention group over time. There was also no significant effect on LDL density (particle size) relative to the control, or any difference between and within treatments in total plasma lipoprotein profiles by density gradient centrifugation. CONCLUSION: These findings provide evidence to suggest that the consumption of cold water prawns, at least in healthy, male subjects, should not be restricted on the grounds of this seafood producing an adverse effect on plasma LDL cholesterol.


Assuntos
Apolipoproteínas/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Ácidos Graxos Ômega-3/administração & dosagem , Penaeidae , Animais , Estudos Cross-Over , Humanos , Masculino , Triglicerídeos/sangue
20.
J Hum Nutr Diet ; 23(2): 120-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20113387

RESUMO

BACKGROUND: Alcohol and polyphenols in wine and fruit juices have been strongly implicated in the favourable effects on of these beverages on vascular function. Despite a wealth of information on the metabolic and vascular effects of alcohol and polyphenols, the combined influences of these substances on vascular function, especially when consumed with food, is poorly understood. A study was designed to determine the effects of a phenolic-rich grape juice, with or without alcohol, on vascular endothelial function in the postprandial state. METHODS: Ten subjects consumed a standard meal with a test drink on three separate occasions. On each occasion, the test drink accompanying the meal was either red grape juice, red grape juice plus alcohol (12% v/v), or water. Endothelial function was measured by flow mediated dilatation (FMD) prior to then 30 and 60 minutes after consuming the meal. Blood samples were taken for the determination of plasma glucose, triacylglycerol (TAG) and non esterified fatty acids (NEFA) at regular intervals. RESULTS: There was a significant effect of the three treatments (P = 0.0026) and time (P = 0.021) on percentage FMD. The meals with the grape juice and grape juice plus alcohol produced similar FMD responses but were both significantly greater than the meal with water. The concentration of plasma glucose, TAG and NEFA were similar after each treatment. CONCLUSION: Alcohol had no effect on vascular function in the early postprandial phase. These findings provide new evidence to support the potential benefit of non-alcoholic components within alcoholic beverages on vascular function in the fed state.


Assuntos
Bebidas , Etanol/farmacologia , Preparações de Plantas/farmacologia , Vasodilatação/efeitos dos fármacos , Vitis , Adolescente , Adulto , Bebidas Alcoólicas , Glicemia/metabolismo , Endotélio Vascular/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Feminino , Frutas , Humanos , Masculino , Valores de Referência , Triglicerídeos/sangue , Água , Adulto Jovem
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