Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 144
Filtrar
1.
Cell Prolif ; : e13650, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721827

RESUMO

Studies have shown that natural products can induce paraptosis in tumour cell lines. Paraptosis is characterized by cytoplasmic vacuolation arising from the endoplasmic reticulum (ER) and mitochondria. The mechanism of paraptosis is unclear; however, dysregulation of Ca2+ homeostasis is believed to affect paraptosis induction. This study investigated the mechanism of cell death induced by a phytocannabinoid ratio in the MCF7 breast cancer cell line. The crystal violet assay was used to detect changes in viability and morphology changes were investigated using light and transmission electron microscopy. Various inhibitors, fluorescent staining with high-content screening, and Western blot analysis were used to investigate different cell death mechanisms. The phytocannabinoid ratio induced significant cell death and cytoplasmic vacuolation in MCF7 cells; however, no apoptosis, necrosis, autophagy, or ferroptosis was detected. Vacuolation induced by phytocannabinoid treatment was inhibited by cycloheximide, suggesting paraptosis induction. The mechanism of paraptosis induction was investigated, and it was found that treatment (1) induced ER dilation and mitochondrial swelling, (2) induced significant ER stress and mitochondrial Ca2+ overload and dysfunction, which appeared to be mediated by the voltage-dependent anion channel, and (3) significantly impaired all mitochondrial metabolic pathways. The data demonstrated that paraptosis induced by the cannabinoid ratio was mediated by Ca2+ flux from the ER to the mitochondria. These findings highlight a novel mechanism of cannabinoid-induced cell death and emphasize the anti-cancer potential of cannabinoid ratios, which exhibited enhanced effects compared to individual cannabinoids.

2.
J Ethnopharmacol ; 267: 113609, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33242621

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Unravelling the anti-diabetic mechanism of action of L. leonurus at adipose, liver, muscle and pancreatic level. AIMS: To investigate the mechanism of action of an organic extract of L. leonurus and marrubiin at the gene level in adipose, liver and muscle tissues of an obese rat model and in a co-culture model. MATERIALS AND METHODS: Obese Wistar rats were fed a cafeteria diet for eight weeks, treated with an extract of L. Leonurus, marrubiin, sulfonylurea and aspirin for two weeks and the level of gene expression of selected markers were investigated across different tissues. The effects mediated by the different treatments were investigated in co-culture cell models involving 3T3-L1 (fat), Chang (liver), C2C12 (muscle) and INS-1 (pancreatic) cells under both normal and hyperglycemic conditions. RESULTS: L. leonurus extract mediated a significant increase in PPAR gamma, glucokinase, FAS and UCP2 gene expression in adipose tissue, whilst the opposite was observed in the liver. At the muscle level, a significant increase in FAS gene expression was observed relative to the obese control rats. Furthermore, the extract as well as marrubiin, modulated improvements in the adipokine profile. The co-culture models showed that the effect mediated by the extract was dependent on, the tissue type as well as the glycemic conditions. CONCLUSIONS: L. Leonurus extract as well as marrubiin exhibit anti-diabetic properties where the mechanism of action is mainly at the adipose tissue level. The increase in expression of the genes of interest mentioned above potentially play a protective role towards the liver and possibly towards the muscle tissues as well.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Lamiaceae , Obesidade/tratamento farmacológico , Extratos Vegetais/farmacologia , Células 3T3 , Adipocinas/genética , Adipocinas/metabolismo , Tecido Adiposo/metabolismo , Animais , Técnicas de Cocultura , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipoglicemiantes/isolamento & purificação , Lamiaceae/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Músculo Esquelético/efeitos dos fármacos , Obesidade/genética , Obesidade/metabolismo , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Extratos Vegetais/isolamento & purificação , Ratos Wistar , Transdução de Sinais
3.
J Phys Condens Matter ; 32(37): 374007, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050188

RESUMO

It is well established that in the low-temperature limit, the two-dimensional quantum Heisenberg antiferromagnet on a square lattice (2DQHAFSL) exhibits an anomaly in its spectrum at short-wavelengths on the zone-boundary. In the vicinity of the [Formula: see text] point the pole in the one-magnon response exhibits a downward dispersion, is heavily damped and attenuated, giving way to an isotropic continuum of excitations extending to high energies. The origin of the anomaly and the presence of the continuum are of current theoretical interest, with suggestions focused around the idea that the latter evidences the existence of spinons in a two-dimensional system. Here we present the results of neutron inelastic scattering experiments and Quantum Monte Carlo calculations on the metallo-organic compound Cu(DCOO)[Formula: see text]D2O (CFTD), an excellent physical realisation of the 2DQHAFSL, designed to investigate how the anomaly at [Formula: see text] evolves up to finite temperatures [Formula: see text]. Our data reveal that on warming the anomaly survives the loss of long-range, three-dimensional order, and that it is thus a robust feature of the two-dimensional system. With further increase of temperature the zone-boundary response gradually softens and broadens, washing out the [Formula: see text] anomaly. This is confirmed by a comparison of our data with the results of finite-temperature Quantum Monte Carlo simulations where the two are found to be in good accord. In the vicinity of the antiferromagnetic zone centre, there was no significant softening of the magnetic excitations over the range of temperatures investigated.

4.
Eur J Neurol ; 27(6): 995-1002, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32078209

RESUMO

BACKGROUND AND PURPOSE: Memory is known to be the most common first symptom in Alzheimer's disease (AD). Assessing non-memory cognitive symptom development in AD is important for understanding disease progression and the potential identification of treatment-responsive subtypes. METHODS: Data from the National Alzheimer's Coordinating Center were examined. Logistic regression models were fitted evaluating the development of judgement, language, visuospatial and attention symptoms at first and second visits to Alzheimer's Disease Centers. Predictors were age and prior symptoms, adjusting for symptom length and sex. The models were then refitted assessing apolipoprotein E ε4 (APOE-ε4) effects. RESULTS: Each decade reduction in presentation age increased the odds of language, visuospatial and attention symptom development at both visits by 8%-18% (P < 0.05, all tests), and judgement symptoms at the second visit by 13% (P < 0.05). Prior symptoms were not equally predictive of symptom development. For example, having first predominant language symptoms carried the lowest risk of developing other first-visit symptoms and having memory symptoms was a stronger predictor of developing judgement than other symptoms. The APOE-ε4 gene showed little impact on symptom development when included as a predictor. CONCLUSIONS: Our findings provide support for the concept that younger-onset AD is associated with the progressive development of more non-memory symptoms beyond the first time point. Associations between symptoms were evident, which may reflect that pathology can remain isolated in a network for some time. APOE-ε4 status had little influence on cognitive symptom development which may indicate that the effect it has occurs very early in the disease course.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/epidemiologia , Apolipoproteína E4 , Cognição , Humanos , Memória , Testes Neuropsicológicos
5.
3 Biotech ; 8(10): 438, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30306007

RESUMO

In vitro studies were conducted to determine the short-term cytotoxic and genotoxic effects of pure glyphosate and two glyphosate formulations (Roundup® and Wipeout®) at concentrations relevant to human exposure using whole blood (cytotoxicity) and various cancer cell lines (cytotoxicity and genotoxicity). Pure glyphosate (pure glyph) and Roundup® (Ro) showed similar non-monotonic toxicological profiles at low dose exposure (from 10 µg/ml), whereas Wipeout® (Wo) demonstrated a monotonic reduction in cell viability from a threshold concentration of 50 µg/ml, when tested in whole blood. We evaluated whether using various cancer cells (the estrogen-E2-responsive HEC1A, MCF7 and the estrogen-insensitive MDA-MB-231) exposed to moderate doses (75-500 µg/ml) would indicate varied toxicity and results indicated significant effects in the HEC1A cancer cells. A non-monotonic reduction in cell viability was observed in HEC1A exposed to pure glyph (75-500 µg/ml) and proliferative effects were observed after exposure to Wo (75, 125 and 250 µg/ml). Genotoxicity assessment (test concentration 500 µg/ml) demonstrated DNA damage in the HEC1A and MDA-MB-231 cells. Adjuvants and/or glyphosate impurities were potential contributing factors of toxicity based on the differential toxicities displayed by Ro and Wo in human whole blood and the HEC1A cells. This study contributes to the existing knowledge about in vitro exposure to moderate concentrations of glyphosate or glyphosate formulations at cytotoxic and genotoxic levels. In addition, a suggestion on the relevance of the estrogen receptor status of the cell lines used is provided, leading to the need to further investigate a potential endocrine disruptive role.

6.
Phytother Res ; 32(6): 1080-1089, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29464872

RESUMO

The objectives of this paper is to investigate, demonstrate, and compare the mechanism of action of phytocannabinoids as antidiabetic and anti-obesity agents in preadipocytes and adipocytes, relative to rosiglitazone and metformin. Briefly, cannabis extract, Δ9 -tetrahydrocannabinol and cannabidiol (in very low dosages) were shown to promote glucose uptake higher or to equivalent levels, reduce fat accumulation, and reverse the insulin-resistant state of 3T3-L1 cells more effectively, relative to rosiglitazone and metformin. The phytocannabinoids had a more pronounced effect in preadipocytes undifferentiated model rather than the differentiated model. They induced a protective effect at the mitochondrial level by preventing overactivity of the succinate dehydrogenase pathway (p < .01), unlike rosiglitazone, through activation of the glycerol-3-phosphate dehydrogenase shuttling system. An increase in oxygen consumption and an increased expression of beta to alpha adrenoceptors (p < .05) in treated cells were noted. These findings contribute toward understanding the mechanism of action of phytocannabinoids in fat cells and highlight the antidiabetic and anti-obesity properties of various phytocannabinoids that could potentially support the treatment of obesity-related insulin resistance.


Assuntos
Adipócitos/efeitos dos fármacos , Fármacos Antiobesidade/uso terapêutico , Canabinoides/uso terapêutico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Fármacos Antiobesidade/farmacologia , Canabinoides/farmacologia , Cannabis , Hipoglicemiantes/farmacologia , Camundongos , Extratos Vegetais/farmacologia
7.
J Thromb Haemost ; 15(11): 2125-2137, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28846831

RESUMO

Essentials Prothrombin complex concentrates (PCCs) may reverse the effect of factor Xa (FXa) inhibitors. We conducted an open-label, randomized, placebo-controlled, three-period crossover study in 15 subjects. Both PCCs rapidly reversed apixaban-mediated decreases in mean endogenous thrombin potential. Four-factor PCC administration had no effect on apixaban pharmacokinetics or anti-FXa activity. SUMMARY: Background Currently, there is no approved reversal agent for direct activated factor Xa (FXa) inhibitors; however, several agents are under investigation, including prothrombin complex concentrates (PCCs). Objective This open-label, randomized, placebo-controlled, three-period crossover study assessed the effect of two four-factor PCCs on apixaban pharmacodynamics and pharmacokinetics in 15 healthy subjects. Methods Subjects received apixaban 10 mg twice daily for 3 days. On day 4, 3 h after apixaban, subjects received a 30-min infusion of 50 IU kg-1 Cofact, Beriplex P/N (Beriplex), or saline. Change in endogenous thrombin potential (ETP), measured with a thrombin generation assay (TGA), was the primary endpoint. Secondary endpoints included changes in other TGA parameters, prothrombin time (PT), International Normalized Ratio (INR), activated partial thromboplastin time, anti-FXa activity, apixaban pharmacokinetics, and safety. Results Apixaban-related changes in ETP and several other pharmacodynamic measures occurred following apixaban administration. Both PCCs reversed apixaban's effect on ETP; the differences in adjusted mean change from pre-PCC baseline to end of infusion were 425 nm min (95% confidence interval [CI] 219.8-630.7 nm min; P < 0.001) for Cofact, and 91 nm min (95% CI - 31.3 to 212.4 nm min; P > 0.05) for Beriplex. Both PCCs returned ETP to pre-apixaban baseline levels 4 h after PCC infusion, versus 45 h for placebo. For both PCCs, mean ETP peaked 21 h after PCC initiation, and then slowly decreased over the following 48 h. Both PCCs reversed apixaban's effect on TGA peak height, PT, and INR. Apixaban pharmacokinetic and anti-FXa profiles were consistent across treatments. Conclusions Cofact and Beriplex reversed apixaban's steady-state effects on several coagulation assessments.


Assuntos
Fatores de Coagulação Sanguínea/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Coagulantes/administração & dosagem , Inibidores do Fator Xa/administração & dosagem , Pirazóis/administração & dosagem , Piridonas/administração & dosagem , Adulto , Fatores de Coagulação Sanguínea/efeitos adversos , Testes de Coagulação Sanguínea , Coagulantes/efeitos adversos , Estudos Cross-Over , Inibidores do Fator Xa/farmacocinética , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Pirazóis/farmacocinética , Piridonas/farmacocinética , Trombina/metabolismo , Adulto Jovem
9.
CPT Pharmacometrics Syst Pharmacol ; 6(5): 340-349, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28547774

RESUMO

Apixaban is approved for treatment of venous thromboembolism (VTE) and prevention of recurrence. Population pharmacokinetics, pharmacokinetics-pharmacodynamics (anti-FXa activity), and exposure-response (binary bleeding and thromboembolic endpoints) of apixaban in VTE treatment subjects were characterized using data from phase I-III studies. Apixaban pharmacokinetics were adequately characterized by a two-compartment model with first-order absorption and elimination. Age, sex, and Asian race had less than 25% impact on exposure, while subjects with severe renal impairment were predicted to have 56% higher exposure than the reference subject (60-year-old non-Asian male weighing 85 kg with creatinine clearance of 100 mL/min). The relationship between apixaban concentration and anti-FXa activity was described by a linear model with a slope estimate of 0.0159 IU/ng. The number of subjects with either a bleeding or thromboembolic event was small, and no statistically significant relationship between apixaban exposure and clinical endpoints could be discerned with a logistic regression analysis.


Assuntos
Inibidores do Fator Xa , Modelos Biológicos , Pirazóis , Piridonas , Tromboembolia Venosa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/farmacocinética , Inibidores do Fator Xa/farmacologia , Inibidores do Fator Xa/uso terapêutico , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Pirazóis/efeitos adversos , Pirazóis/farmacocinética , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Piridonas/efeitos adversos , Piridonas/farmacocinética , Piridonas/farmacologia , Piridonas/uso terapêutico , Resultado do Tratamento , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/metabolismo , Adulto Jovem
11.
J Appl Microbiol ; 122(4): 921-931, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28132403

RESUMO

AIMS: This study investigates the effect that aqueous extracts of Tulbaghia violacea Harv. harbouring plant saponins, phenolics and tannins have on Aspergillus flavus ß-(1,3) glucan and chitin synthesis. METHODS AND RESULTS: Aspergillus flavus was treated with various subinhibitory concentrations of an aqueous T. violacea plant extract and the ß-(1,3) glucan and chitin content was determined together with glucan synthase and chitin synthase production respectively. CONCLUSIONS: The aqueous extract caused a significant decline (P < 0·05) in ß-glucan production in A. flavus in a dose-dependent manner when compared to the untreated sample. Further investigations showed a decrease in ß-glucan synthase production as the concentration of the plant extract was increased. A significant reduction in total chitin content corresponding to a decrease in chitin synthase production in the presence of the plant extract was also found. SIGNIFICANCE AND IMPACT OF THE STUDY: The broad spectrum activity and the efficacy of aqueous T. violacea plant extract on both ß-glucan and chitin synthesis may limit the potential of the fungus developing resistance towards it and therefore the extract is an ideal candidate for use as a potential antifungal agent.


Assuntos
Allium/química , Antifúngicos/farmacologia , Aspergillus flavus/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/metabolismo , Aspergillus flavus/enzimologia , Aspergillus flavus/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Quitina/metabolismo , Glucanos/farmacologia , Glucosiltransferases/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , beta-Glucanas/metabolismo
12.
Sci Rep ; 7: 41013, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28112195

RESUMO

Aviation and space applications can benefit significantly from lightweight organic electronics, now spanning from displays to logics, because of the vital importance of minimising payload (size and mass). It is thus crucial to assess the damage caused to such materials by cosmic rays and neutrons, which pose a variety of hazards through atomic displacements following neutron-nucleus collisions. Here we report the first study of the neutron radiation tolerance of two poly(thiophene)s-based organic semiconductors: poly(3-hexylthiophene-2,5-diyl), P3HT, and the liquid-crystalline poly(2,5-bis (3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene), PBTTT. We combine spectroscopic investigations with characterisation of intrinsic charge mobility to show that PBTTT exhibits significantly higher tolerance than P3HT. We explain this in terms of a superior chemical, structural and conformational stability of PBTTT, which can be ascribed to its higher crystallinity, in turn induced by a combination of molecular design features. Our approach can be used to develop design strategies for better neutron radiation-tolerant materials, thus paving the way for organic semiconductors to enter avionics and space applications.

13.
AJNR Am J Neuroradiol ; 38(2): 336-342, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28056453

RESUMO

BACKGROUND AND PURPOSE: Although it is a potentially powerful presurgical tool, fMRI can be fraught with artifacts, leading to interpretive errors, many of which are not fully accounted for in routinely applied correction methods. The purpose of this investigation was to evaluate the effects of data denoising by independent component analysis in patients undergoing preoperative evaluation for glioma resection compared with more routinely applied correction methods such as realignment or motion scrubbing. MATERIALS AND METHODS: Thirty-five functional runs (both motor and language) in 12 consecutive patients with glioma were analyzed retrospectively by double-blind review. Data were processed and compared with the following: 1) realignment alone, 2) motion scrubbing, 3) independent component analysis denoising, and 4) both independent component analysis denoising and motion scrubbing. Primary outcome measures included a change in false-positives, false-negatives, z score, and diagnostic rating. RESULTS: Independent component analysis denoising reduced false-positives in 63% of studies versus realignment alone. There was also an increase in the z score in areas of true activation in 71.4% of studies. Areas of new expected activation (previous false-negatives) were revealed in 34.4% of cases with independent component analysis denoising versus motion scrubbing or realignment alone. Of studies deemed nondiagnostic with realignment or motion scrubbing alone, 65% were considered diagnostic after independent component analysis denoising. CONCLUSIONS: The addition of independent component analysis denoising of fMRI data in preoperative patients with glioma has a significant impact on data quality, resulting in reduced false-positives and an increase in true-positives compared with more commonly applied motion scrubbing or simple realignment methods.


Assuntos
Artefatos , Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Cirurgia Assistida por Computador/métodos , Humanos , Masculino
14.
Clin Radiol ; 72(1): 41-51, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27927488

RESUMO

AIM: To evaluate major/minor discrepancy rates for provisional (initial) and addendum (supplementary senior review) emergency computed tomography (CT) reports in patients presenting with non-traumatic abdominal pain. MATERIALS AND METHODS: Ethical approval for this type of study is not required in the UK. All radiology departments with an approved lead for audit registered with the Royal College of Radiologists were invited to participate in this retrospective audit. The first 50 consecutive patients (25 surgical, 25 non-surgical) who underwent emergency abdominal CT for non-traumatic abdominal pain in 2013 were included. Statistical analyses were performed to identify organisational and report/patient-related variables that might be associated with major discrepancy. RESULTS: One hundred and nine (58%) of 188 departments supplied data to the study with a total of 4,931 patients (2,568 surgical, 2,363 non-surgical). The audit standard for provisional report major discrepancy was achieved for registrars (target <10%, achieved 4.6%), for on-site consultants (target <5%, achieved 3.1%) and consultant addendum (target <5%, achieved 2.9%). Off-site reporters failed to meet the standard target (<5%, achieved 8.7% overall and 12.7% in surgical patients). The standard for patients coming to harm was not met in the surgical group (target <1%, achieved 1.5%) and was narrowly missed overall (target <1%, achieved 1%). CONCLUSION: This study should be used to provide impetus to improve aspects of out-of-hours CT reporting. Clear benefits of CT interpretation/review by on-site and more senior (consultant) radiologists have been demonstrated.


Assuntos
Dor Abdominal/diagnóstico por imagem , Dor Abdominal/epidemiologia , Erros de Diagnóstico/estatística & dados numéricos , Serviços Médicos de Emergência/estatística & dados numéricos , Radiografia Abdominal/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Traumatismos Abdominais/diagnóstico , Traumatismos Abdominais/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Competência Clínica , Erros de Diagnóstico/prevenção & controle , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Reino Unido/epidemiologia , Adulto Jovem
15.
AJNR Am J Neuroradiol ; 36(8): 1529-35, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25882281

RESUMO

BACKGROUND AND PURPOSE: Acute invasive fungal rhinosinusitis carries a high mortality rate. An easy-to-use and accurate predictive imaging model is currently lacking. We assessed the performance of various CT findings for the identification of acute invasive fungal rhinosinusitis and synthesized a simple and robust diagnostic model to serve as an easily applicable screening tool for at-risk patients. MATERIALS AND METHODS: Two blinded neuroradiologists retrospectively graded 23 prespecified imaging abnormalities in the craniofacial region on craniofacial CT examinations from 42 patients with pathology-proven acute invasive fungal rhinosinusitis and 42 control patients proved negative for acute invasive fungal rhinosinusitis from the same high-risk population. A third blinded neuroradiologist decided discrepancies. Specificity, sensitivity, positive predictive value, and negative predictive value were determined for all individual variables. The 23 variables were evaluated for intercorrelations and univariate correlations and were interrogated by using stepwise linear regression. RESULTS: Given the low predictive value of any individual variable, a 7-variable model (periantral fat, bone dehiscence, orbital invasion, septal ulceration, pterygopalatine fossa, nasolacrimal duct, and lacrimal sac) was synthesized on the basis of multivariate analysis. The presence of abnormality involving a single variable in the model has an 87% positive predictive value, 95% negative predictive value, 95% sensitivity, and 86% specificity (R(2) = 0.661). A positive outcome in any 2 of the model variables predicted acute invasive fungal rhinosinusitis with 100% specificity and 100% positive predictive value. CONCLUSIONS: Our 7-variable CT-based model provides an easily applicable and robust screening tool to triage patients at risk for acute invasive fungal rhinosinusitis into a disease-positive or -negative category with a high degree of confidence.


Assuntos
Micoses/diagnóstico por imagem , Rinite/diagnóstico por imagem , Sinusite/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rinite/microbiologia , Sensibilidade e Especificidade , Sinusite/microbiologia
16.
CPT Pharmacometrics Syst Pharmacol ; 3: e136, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25229619

RESUMO

Population pharmacokinetic (PK) and exposure-response analyses of apixaban were performed using data from phase I-III studies to predict bleeding risks for patients receiving apixaban 2.5 mg b.i.d. after total knee or hip replacement (TKR, THR) surgery (N = 5,510). Renal function, age, gender, and body weight impacted apixaban exposure. Bleeding risk increased as a function of exposure. Predicted bleeding frequencies for TKR and THR populations at risk for high apixaban exposure (female, age > 75 years, calculated creatinine clearance (cCrCL) < 30 ml/min, body weight < 50 kg) (6.85 and 10.3%, respectively) were comparable to the reference population (male/female, age 65-75 years, cCrCL ≥ 80 ml/min, body weight 65-85 kg) (6.18 and 9.32%, respectively). A 100% increase in apixaban exposure is expected to raise bleeding frequencies to 7.25% (TKR) and 10.9% (THR), whereas a 200% increase would raise them to 8.49 and 12.7%. Coexistence of combined patient risk factors or doubling of exposure is not likely to result in a substantial, clinically relevant increase in bleeding risk with 2.5 mg b.i.d. apixaban.

17.
Phys Rev Lett ; 111(13): 137205, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24116814

RESUMO

The space-and time-dependent response of many-body quantum systems is the most informative aspect of their emergent behavior. The dynamical structure factor, experimentally measurable using neutron scattering, can map this response in wave vector and energy with great detail, allowing theories to be quantitatively tested to high accuracy. Here, we present a comparison between neutron scattering measurements on the one-dimensional spin-1/2 Heisenberg antiferromagnet KCuF3, and recent state-of-the-art theoretical methods based on integrability and density matrix renormalization group simulations. The unprecedented quantitative agreement shows that precise descriptions of strongly correlated states at all distance, time, and temperature scales are now possible, and highlights the need to apply these novel techniques to other problems in low-dimensional magnetism.

18.
J Phys Condens Matter ; 25(20): 206001, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23603609

RESUMO

The magnetic symmetry and structure of the non-Fermi liquid heavy fermion compound CeNiGa2 has been determined by neutron powder diffraction. The orthorhombic CeNiGa2 compound orders antiferromagnetically below 4.4(2) K at ambient pressure with a magnetic moment magnitude of µCe = 0.80(4) µB for moments aligned along the c-axis. The magnetic (Shubnikov) space group is C2cm'm'm. The nature of the magnetic order of CeNiGa2 is further elucidated by neutron diffraction at elevated pressures up to 4.5 kbar, allowing for the confirmation of a critical pressure PC of about 4.2(2) kbar above which the magnetic moment ordering is suppressed.

19.
J Genet Couns ; 21(6): 862-72, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22825406

RESUMO

The objective of this study was to explore how a parent-to-parent support network could impact parents of a child with a structural birth defect by specifically looking at parents' continued needs, aspects influencing their participation in support networks, and their recommendations. Structural birth defects occur in approximately 3 % of all infants, representing a significant public health issue. For many reasons, parents are uniquely qualified to provide support to each other. Data were collected retrospectively through a qualitative approach of focus groups or one-on-one interviews. Thirty one parents of infants registered in the Utah Birth Defect Network participated in the study. Three themes emerged, "current sources and inconsistencies in parent-to-parent-support," "aspects that influence participation in parent-to-parent network," and "recommendations for a parent-to-parent program." Health care providers need to be aware of the services and inform parents about these options. A statewide parent-to-parent network integrated into all hospitals would be a valuable resource to facilitate sharing of issues related to caring for an infant or child with a birth defect.


Assuntos
Anormalidades Congênitas/psicologia , Necessidades e Demandas de Serviços de Saúde , Pais/psicologia , Apoio Social , Pré-Escolar , Anormalidades Congênitas/fisiopatologia , Feminino , Humanos , Lactente , Masculino
20.
Clin Radiol ; 67(6): 523-30, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22397729

RESUMO

AIM: To report the results of a nationwide audit of the accuracy of magnetic resonance imaging (MRI) staging in uterine body cancer when staging myometrial invasion, cervical extension, and lymph node spread. MATERIALS AND METHODS: All UK radiology departments were invited to participate using a web-based tool for submitting anonymized data for a 12 month period. MRI staging was compared with histopathological staging using target accuracies of 85, 86, and 70% respectively. RESULTS: Of the departments performing MRI staging of endometrial cancer, 37/87 departments contributed. Targets for MRI staging were achieved for two of the three standards nationally with diagnostic accuracy for depth of myometrial invasion, 82%; for cervical extension, 90%; and for pelvic nodal involvement, 94%; the latter two being well above the targets. However, only 13/37 (35%) of individual centres met the target for assessing depth of myometrial invasion, 31/36 (86%) for cervical extension and 31/34 (91%) for pelvic nodal involvement. Statistical analysis demonstrated no significant difference for the use of intravenous contrast medium, but did show some evidence of increasing accuracy in assessment of depth of myometrial invasion with increasing caseload. CONCLUSION: Overall performance in the UK was good, with only the target for assessment of depth of myometrial invasion not being met. Inter-departmental variation was seen. One factor that may improve performance in assessment of myometrial invasion is a higher caseload. No other clear factor to improve performance were identified.


Assuntos
Imageamento por Ressonância Magnética/normas , Auditoria Médica/métodos , Invasividade Neoplásica/patologia , Neoplasias Uterinas/patologia , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Miométrio/patologia , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Reino Unido , Neoplasias do Colo do Útero/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA