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1.
J Biol Chem ; 296: 100263, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33837744

RESUMO

The development of a targeted therapy would significantly improve the treatment of periodontitis and its associated diseases including Alzheimer's disease, rheumatoid arthritis, and cardiovascular diseases. Glutaminyl cyclases (QCs) from the oral pathogens Porphyromonas gingivalis, Tannerella forsythia, and Prevotella intermedia represent attractive target enzymes for small-molecule inhibitor development, as their action is likely to stabilize essential periplasmic and outer membrane proteins by N-terminal pyroglutamination. In contrast to other microbial QCs that utilize the so-called type I enzymes, these oral pathogens possess sequences corresponding to type II QCs, observed hitherto only in animals. However, whether differences between these bacteroidal QCs and animal QCs are sufficient to enable development of selective inhibitors is not clear. To learn more, we recombinantly expressed all three QCs. They exhibit comparable catalytic efficiencies and are inhibited by metal chelators. Crystal structures of the enzymes from P. gingivalis (PgQC) and T. forsythia (TfQC) reveal a tertiary structure composed of an eight-stranded ß-sheet surrounded by seven α-helices, typical of animal type II QCs. In each case, an active site Zn ion is tetrahedrally coordinated by conserved residues. Nevertheless, significant differences to mammalian enzymes are found around the active site of the bacteroidal enzymes. Application of a PgQC-selective inhibitor described here for the first time results in growth inhibition of two P. gingivalis clinical isolates in a dose-dependent manner. The insights gained by these studies will assist in the development of highly specific small-molecule bacteroidal QC inhibitors, paving the way for alternative therapies against periodontitis and associated diseases.


Assuntos
Aminoaciltransferases/química , Periodontite/microbiologia , Porphyromonas gingivalis/enzimologia , Prevotella intermedia/enzimologia , Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/genética , Aminoaciltransferases/ultraestrutura , Domínio Catalítico/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Periodontite/tratamento farmacológico , Periodontite/genética , Porphyromonas gingivalis/patogenicidade , Prevotella intermedia/patogenicidade , Estrutura Terciária de Proteína/efeitos dos fármacos , Ácido Pirrolidonocarboxílico/química , Ácido Pirrolidonocarboxílico/metabolismo , Tannerella forsythia/enzimologia , Tannerella forsythia/patogenicidade
2.
J Biol Chem ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402424

RESUMO

The development of a targeted therapy would significantly improve the treatment of periodontitis and its associated diseases including Alzheimer Disease, rheumatoid arthritis, and cardiovascular diseases. Glutaminyl cyclases (QCs) from the oral pathogens Porphyromonas gingivalis, Tannerella forsythia and Prevotella intermedia represent attractive target enzymes for small-molecule inhibitor development, as their action is likely to stabilize essential periplasmic and outer membrane proteins by N-terminal pyroglutamination. In contrast to other microbial QCs that utilize so-called type I enzymes, these oral pathogens possess sequences corresponding to type II QCs, observed hitherto only in animals. However, whether differences between these bacteroidal QCs and animal QCs are sufficient to enable development of selective inhibitors is not clear. To learn more, we recombinantly expressed all three QCs. They exhibit comparable catalytic efficiencies and are inhibited by metal chelators. Crystal structures  of the enzymes from P. gingivalis (PgQC) and T. forsythia (TfQC) reveal a tertiary structure composed of an eight-stranded ß-sheet surrounded by seven α-helices, typical of animal type II QCs. In each case, an active site Zn ion is tetrahedrally coordinated by conserved residues. Nevertheless, significant differences to mammalian enzymes are found around the active site of the bacteroidal enzymes. Application of a PgQC-selective inhibitor described here for the first time results in growth inhibition of two P. gingivalis clinical isolates in a dose dependent manner. The insights gained by these studies will assist in the development of highly specific small-molecule bacteroidal QC inhibitors, paving the way for alternative therapies against periodontitis and associated diseases.

3.
Eur Heart J ; 41(36): 3421-3432, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32578850

RESUMO

AIM: We tested the hypothesis that dapagliflozin may regress left ventricular hypertrophy (LVH) in people with type 2 diabetes (T2D). METHODS AND RESULTS: We randomly assigned 66 people (mean age 67 ± 7 years, 38 males) with T2D, LVH, and controlled blood pressure (BP) to receive dapagliflozin 10 mg once daily or placebo for 12 months. Primary endpoint was change in absolute left ventricular mass (LVM), assessed by cardiac magnetic resonance imaging. In the intention-to-treat analysis, dapagliflozin significantly reduced LVM compared with placebo with an absolute mean change of -2.82g [95% confidence interval (CI): -5.13 to -0.51, P = 0.018]. Additional sensitivity analysis adjusting for baseline LVM, baseline BP, weight, and systolic BP change showed the LVM change to remain statistically significant (mean change -2.92g; 95% CI: -5.45 to -0.38, P = 0.025). Dapagliflozin significantly reduced pre-specified secondary endpoints including ambulatory 24-h systolic BP (P = 0.012), nocturnal systolic BP (P = 0.017), body weight (P < 0.001), visceral adipose tissue (VAT) (P < 0.001), subcutaneous adipose tissue (SCAT) (P = 0.001), insulin resistance, Homeostatic Model Assessment of Insulin Resistance (P = 0.017), and high-sensitivity C-reactive protein (hsCRP) (P = 0.049). CONCLUSION: Dapagliflozin treatment significantly reduced LVM in people with T2D and LVH. This reduction in LVM was accompanied by reductions in systolic BP, body weight, visceral and SCAT, insulin resistance, and hsCRP. The regression of LVM suggests dapagliflozin can initiate reverse remodelling and changes in left ventricular structure that may partly contribute to the cardio-protective effects of dapagliflozin. CLINICALTRIALS.GOV IDENTIFIER: NCT02956811.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Idoso , Compostos Benzidrílicos , Pressão Sanguínea , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos , Ventrículos do Coração , Humanos , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Hipertrofia Ventricular Esquerda/prevenção & controle , Masculino , Pessoa de Meia-Idade
4.
J Ultrasound Med ; 39(5): 875-881, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31724207

RESUMO

OBJECTIVES: Arterial stiffness has been proposed as a marker of arteriovenous fistula failure and can be measured locally by using ultrasound shear wave elastography (SWE). This preliminary study aimed to assess whether SWE measurements of the brachial artery were associated with arteriovenous fistula failure. METHODS: Data were collected on patients who were indicated for fistula creation. Preoperative and postoperative vessel diameters from B-mode ultrasound, brachial artery SWE maps, and demographic data were collected. Logistic and linear regression analyses were used to determine whether any of these variables were related to the outcome of the fistula 3 months after creation. RESULTS: Data were acquired for 33 patients. Shear wave velocity values decreased after fistula creation (mean ± SD, -1.2 ± 1 m/s; P < .05). No parameters were associated with failure of the fistula in the logistic regression analysis. CONCLUSIONS: No markers were related to fistula failure, but a decrease in the shear wave velocity was observed in the brachial arteries after fistula creation, indicating increased compliance.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Técnicas de Imagem por Elasticidade/métodos , Rigidez Vascular/fisiologia , Idoso , Derivação Arteriovenosa Cirúrgica/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Eur Heart J ; 40(41): 3409-3417, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30993313

RESUMO

AIM: We tested the hypothesis that metformin may regress left ventricular hypertrophy (LVH) in patients who have coronary artery disease (CAD), with insulin resistance (IR) and/or pre-diabetes. METHODS AND RESULTS: We randomly assigned 68 patients (mean age 65 ± 8 years) without diabetes who have CAD with IR and/or pre-diabetes to receive either metformin XL (2000 mg daily dose) or placebo for 12 months. Primary endpoint was change in left ventricular mass indexed to height1.7 (LVMI), assessed by magnetic resonance imaging. In the modified intention-to-treat analysis (n = 63), metformin treatment significantly reduced LVMI compared with placebo group (absolute mean difference -1.37 (95% confidence interval: -2.63 to -0.12, P = 0.033). Metformin also significantly reduced other secondary study endpoints such as: LVM (P = 0.032), body weight (P = 0.001), subcutaneous adipose tissue (P = 0.024), office systolic blood pressure (BP, P = 0.022) and concentration of thiobarbituric acid reactive substances, a biomarker for oxidative stress (P = 0.04). The glycated haemoglobin A1C concentration and fasting IR index did not differ between study groups at the end of the study. CONCLUSION: Metformin treatment significantly reduced LVMI, LVM, office systolic BP, body weight, and oxidative stress. Although LVH is a good surrogate marker of cardiovascular (CV) outcome, conclusive evidence for the cardio-protective role of metformin is required from large CV outcomes trials.


Assuntos
Doença da Artéria Coronariana/complicações , Hipertrofia Ventricular Esquerda , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Estado Pré-Diabético , Idoso , Peso Corporal/efeitos dos fármacos , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Resistência à Insulina , Masculino , Metformina/efeitos adversos , Metformina/farmacologia , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Estado Pré-Diabético/complicações , Estado Pré-Diabético/tratamento farmacológico , Resultado do Tratamento
6.
Eur Radiol ; 29(5): 2340-2349, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30488106

RESUMO

OBJECTIVES: To compare aortic size and stiffness parameters on MRI between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) patients with aortic stenosis (AS). METHODS: MRI was performed in 174 patients with asymptomatic moderate-severe AS (mean AVAI 0.57 ± 0.14 cm2/m2) and 23 controls on 3T scanners. Valve morphology was available/analysable in 169 patients: 63 BAV (41 type-I, 22 type-II) and 106 TAV. Aortic cross-sectional areas were measured at the level of the pulmonary artery bifurcation. The ascending and descending aorta (AA, DA) distensibility, and pulse wave velocity (PWV) around the aortic arch were calculated. RESULTS: The AA and DA areas were lower in the controls, with no difference in DA distensibility or PWV, but slightly lower AA distensibility than in the patient group. With increasing age, there was a decrease in distensibility and an increase in PWV. After correcting for age, the AA maximum cross-sectional area was higher in bicuspid vs. tricuspid patients (12.97 [11.10, 15.59] vs. 10.06 [8.57, 12.04] cm2, p < 0.001), but there were no significant differences in AA distensibility (p = 0.099), DA distensibility (p = 0.498) or PWV (p = 0.235). Patients with BAV type-II valves demonstrated a significantly higher AA distensibility and lower PWV compared to type-I, despite a trend towards higher AA area. CONCLUSIONS: In patients with significant AS, BAV patients do not have increased aortic stiffness compared to those with TAV despite increased ascending aortic dimensions. Those with type-II BAV have less aortic stiffness despite greater dimensions. These results demonstrate a dissociation between aortic dilatation and stiffness and suggest that altered flow patterns may play a role. KEY POINTS: • Both cellular abnormalities secondary to genetic differences and abnormal flow patterns have been implicated in the pathophysiology of aortic dilatation and increased vascular complications associated with bicuspid aortic valves (BAV). • We demonstrate an increased ascending aortic size in patients with BAV and moderate to severe AS compared to TAV and controls, but no difference in aortic stiffness parameters, therefore suggesting a dissociation between dilatation and stiffness. • Sub-group analysis showed greater aortic size but lower stiffness parameters in those with BAV type-II AS compared to BAV type-I.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Valva Tricúspide/diagnóstico por imagem , Rigidez Vascular , Adulto , Idoso , Aorta/fisiopatologia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/patologia , Doença da Válvula Aórtica Bicúspide , Dilatação Patológica , Feminino , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso , Valva Tricúspide/patologia , Valva Tricúspide/fisiopatologia
7.
MAGMA ; 31(6): 735-745, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30132298

RESUMO

OBJECTIVE: To compare non-contrast enhanced MRI with ultrasound (US) for measurement of arm blood vessel geometries and flow velocities in volunteers and patients with end-stage renal disease. MATERIALS AND METHODS: Subjects were scanned using US (reference standard), and MRI 2D time-of-flight (ToF), 2D phase contrast (PC), and 3D multi-echo data image combination (MEDIC). Patients were also scanned after arteriovenous fistula (AVF) surgery. RESULTS: For mean vessel diameters (radial and brachial arteries; cephalic vein) MEDIC measurements were similar to US (p > 0.05). However, ToF underestimated the mean diameter of the cephalic vein relative to US (p < 0.05). For arterial velocity measurements, the mean values derived by PC-MR and US were similar (p > 0.05). Post-operatively, the intra-luminal signal intensity was hypo-intense at the anastomosis site using ToF and MEDIC. At the same site the outer boundary of the vessel was consistently lost on ToF, but remained clearly delineated on the MEDIC images. DISCUSSION: With the exception of ToF, the MRI data demonstrated excellent agreement with US for measurements of vessel geometry and flow velocity. Further, the ability to clearly delineate the post-surgery vessel edges with MEDIC MRI suggests that the technique may be useful for surveillance after AVF creation or for patient-specific modelling studies.


Assuntos
Fístula Arteriovenosa/diagnóstico por imagem , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/cirurgia , Imageamento por Ressonância Magnética/métodos , Diálise Renal/efeitos adversos , Adulto , Derivação Arteriovenosa Cirúrgica , Velocidade do Fluxo Sanguíneo , Artéria Braquial/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Pessoa de Meia-Idade , Projetos Piloto , Período Pré-Operatório , Artéria Radial/cirurgia , Diálise Renal/métodos , Ultrassonografia
8.
Biol Chem ; 396(4): 377-84, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25720118

RESUMO

Gingipain proteases are important virulence factors from the periodontal pathogen Porphyromonas gingivalis and are the target of many in vitro studies. Due to their close biochemical properties, purification of individual gingipains is difficult and requires multiple chromatographic steps. In this study, we demonstrate that insertion of a hexahistidine affinity tag upstream of a C-terminal outer membrane translocation signal in RgpB gingipain leads to the secretion of a soluble, mature form of RgpB bearing the affinity tag that can easily be purified by nickel-chelating affinity chromatography. The final product obtained high yielding high purity is biochemically indistinguishable from the native RgpB enzyme.


Assuntos
Adesinas Bacterianas/isolamento & purificação , Adesinas Bacterianas/metabolismo , Cisteína Endopeptidases/isolamento & purificação , Cisteína Endopeptidases/metabolismo , Porphyromonas gingivalis/metabolismo , Adesinas Bacterianas/química , Infecções por Bacteroidaceae/microbiologia , Cromatografia de Afinidade , Cisteína Endopeptidases/química , Cisteína Endopeptidases Gingipaínas , Humanos , Porphyromonas gingivalis/química , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
9.
Biochim Biophys Acta ; 1830(8): 4218-28, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23583629

RESUMO

BACKGROUND: Arginine-specific (RgpB and RgpA) and lysine-specific (Kgp) gingipains are secretory cysteine proteinases of Porphyromonas gingivalis that act as important virulence factors for the organism. They are translated as zymogens with both N- and C-terminal extensions, which are proteolytically cleaved during secretion. In this report, we describe and characterize inhibition of the gingipains by their N-terminal prodomains to maintain latency during their export through the cellular compartments. METHODS: Recombinant forms of various prodomains (PD) were analyzed for their interaction with mature gingipains. The kinetics of their inhibition of proteolytic activity along with the formation of stable inhibitory complexes with native gingipains was studied by gel filtration, native PAGE and substrate hydrolysis. RESULTS: PDRgpB and PDRgpA formed tight complexes with arginine-specific gingipains (Ki in the range from 6.2nM to 0.85nM). In contrast, PDKgp showed no inhibitory activity. A conserved Arg-102 residue in PDRgpB and PDRgpA was recognized as the P1 residue. Mutation of Arg-102 to Lys reduced inhibitory potency of PDRgpB by one order of magnitude while its substitutions with Ala, Gln or Gly totally abolished the PD inhibitory activity. Covalent modification of the catalytic cysteine with tosyl-l-Lys-chloromethylketone (TLCK) or H-D-Phe-Arg-chloromethylketone did not affect formation of the stable complex. CONCLUSION: Latency of arginine-specific progingipains is efficiently exerted by N-terminal prodomains thus protecting the periplasm from potentially damaging effect of prematurely activated gingipains. GENERAL SIGNIFICANCE: Blocking progingipain activation may offer an attractive strategy to attenuate P. gingivalis pathogenicity.


Assuntos
Adesinas Bacterianas/química , Cisteína Endopeptidases/química , Inibidores de Cisteína Proteinase/farmacologia , Fragmentos de Peptídeos/farmacologia , Porphyromonas gingivalis/patogenicidade , Adesinas Bacterianas/efeitos dos fármacos , Adesinas Bacterianas/metabolismo , Cisteína Endopeptidases/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Ativação Enzimática , Cisteína Endopeptidases Gingipaínas , Glicosilação , Estrutura Terciária de Proteína , Proteínas Recombinantes/farmacologia
10.
Curr Atheroscler Rep ; 16(6): 416, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24743868

RESUMO

Renal artery stensosis (RAS) continues to be a problem for clinicians, with no clear consensus on how to investigate and assess the clinical significance of stenotic lesions and manage the findings. RAS caused by fibromuscular dysplasia is probably commoner than previously appreciated, should be actively looked for in younger hypertensive patients and can be managed successfully with angioplasty. Atheromatous RAS is associated with increased incidence of cardiovascular events and increased cardiovascular mortality, and is likely to be seen with increasing frequency. Evidence from large clinical trials has led clinicians away from recommending interventional revascularisation towards aggressive medical management. There is now interest in looking more closely at patient selection for intervention, with focus on intervening only in patients with the highest-risk presentations such as flash pulmonary oedema, rapidly declining renal function and severe resistant hypertension. The potential benefits in terms of improving hard cardiovascular outcomes may outweigh the risks of intervention in this group, and further research is needed.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Obstrução da Artéria Renal/diagnóstico , Obstrução da Artéria Renal/terapia , Stents , Angioplastia/métodos , Aterosclerose/complicações , Aterosclerose/terapia , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico , Obstrução da Artéria Renal/complicações
11.
Clin Cancer Res ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819400

RESUMO

PURPOSE: Estrogen Receptor (ER) alpha signaling is a known driver of ER-positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer. Combining endocrine therapy (ET) such as fulvestrant with CDK4/6, mTOR or PI3K inhibitors is now a central strategy for the treatment of ER+ advanced breast cancer. However, suboptimal ER inhibition and resistance resulting from ESR1 mutation dictates that new therapies are needed. EXPERIMENTAL DESIGN: A medicinal chemistry campaign identified vepdegestrant (ARV-471), a selective, orally bioavailable, potent small molecule PROteolysis-TArgeting Chimera (PROTAC®) degrader of ER. We used biochemical and intracellular target engagement assays to demonstrate the mechanism of action of vepdegestrant, and ESR1 wild-type and mutant ER+ preclinical breast cancer models to demonstrate ER degradation-mediated tumor growth inhibition. RESULTS: Vepdegestrant induced ≥90% degradation of wild-type (WT) and mutant ER, inhibited ER-dependent breast cancer cell line proliferation in-vitro and achieved significant tumor growth inhibition (TGI) (87-123%) in MCF7 orthotopic xenograft models, better than the ET agent fulvestrant (31-80% TGI). In the hormone-independent ER Y537S patient derived xenograft (PDX) breast cancer model ST941/HI, vepdegestrant achieved tumor regressions and was similarly efficacious in the ST941/HI/PBR palbociclib-resistant model (102% TGI). Vepdegestrant induced robust tumor regressions in combination with each of the CDK4/6 inhibitors palbociclib, abemaciclib, and ribociclib, the mTOR inhibitor everolimus, and the PI3K inhibitors alpelisib and inavolisib. CONCLUSIONS: Vepdegestrant achieved greater ER degradation in-vivo compared to fulvestrant, which correlated with improved tumor growth inhibition, suggesting vepdegestrant could be a more effective backbone ET for patients with ER+/HER2- breast cancer.

12.
J Pharmacol Exp Ther ; 344(3): 686-95, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23275065

RESUMO

A hallmark of Alzheimer's disease (AD) pathology is the accumulation of brain amyloid ß-peptide (Aß), generated by γ-secretase-mediated cleavage of the amyloid precursor protein (APP). Therefore, γ-secretase inhibitors (GSIs) may lower brain Aß and offer a potential new approach to treat AD. As γ-secretase also cleaves Notch proteins, GSIs can have undesirable effects due to interference with Notch signaling. Avagacestat (BMS-708163) is a GSI developed for selective inhibition of APP over Notch cleavage. Avagacestat inhibition of APP and Notch cleavage was evaluated in cell culture by measuring levels of Aß and human Notch proteins. In rats, dogs, and humans, selectivity was evaluated by measuring plasma blood concentrations in relation to effects on cerebrospinal fluid (CSF) Aß levels and Notch-related toxicities. Measurements of Notch-related toxicity included goblet cell metaplasia in the gut, marginal-zone depletion in the spleen, reductions in B cells, and changes in expression of the Notch-regulated hairy and enhancer of split homolog-1 from blood cells. In rats and dogs, acute administration of avagacestat robustly reduced CSF Aß40 and Aß42 levels similarly. Chronic administration in rats and dogs, and 28-day, single- and multiple-ascending-dose administration in healthy human subjects caused similar exposure-dependent reductions in CSF Aß40. Consistent with the 137-fold selectivity measured in cell culture, we identified doses of avagacestat that reduce CSF Aß levels without causing Notch-related toxicities. Our results demonstrate the selectivity of avagacestat for APP over Notch cleavage, supporting further evaluation of avagacestat for AD therapy.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Precursor de Proteína beta-Amiloide/antagonistas & inibidores , Oxidiazóis/farmacologia , Sulfonamidas/farmacologia , Adolescente , Adulto , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Células Cultivadas , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
13.
Clin Endocrinol (Oxf) ; 79(4): 484-90, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23469866

RESUMO

OBJECTIVE: The significant role of corticosteroids in hypertension and cardiovascular disease highlights the importance of the adrenal gland in these disorders. The ability to correlate corticosteroid production with adrenal volume offers a novel research tool and intermediate phenotype in cardiovascular disease. The aim of this study was to develop and validate the use of magnetic resonance imaging (MRI) in adrenal volume assessment and investigate whether this associates with corticosteroid production. DESIGN/METHODS: Twenty normotensive men underwent noncontrast 1·5T MRI scanning of adrenals, measurement of blood pressure and plasma corticosteroids. Left adrenal volume was calculated twice using standard segmentation software by four independent observers with differing levels of clinical expertise and segmentation experience. To optimize this process, adrenal 'phantoms' with known fixed volumes underwent MRI scanning and analysis by two observers. RESULTS: Intra-observer coefficients of repeatability (CoRs) in phantoms ranged from 0·23 to 0·43 ml (interobserver CoR 0·48 ml). In the subject group, mean adrenal volumes were 3·99-5·82 ml with intra-observer CoRs 0·27-1·94 ml. Interobserver variability was 2·73 ml. Segmentation expertise was the main factor affecting variability, with experienced observers having the lowest CoRs; clinical knowledge was a factor when combined with segmentation experience. Mean adrenal volume correlated with plasma glucocorticoids (r = 0·523, P < 0·05) and aldosterone (r = 0·515, P < 0·05) for the most experienced observer only. CONCLUSIONS: Measurement of adrenal volume using MRI is challenging; most accurate volumes are achieved using a single observer with both segmentation experience and anatomical knowledge. The data also provide novel preliminary evidence that adrenal gland volume may be associated with plasma corticosteroid concentrations supporting further study of adrenal volume and steroid production across a range of blood pressures.


Assuntos
Corticosteroides/sangue , Glândulas Suprarrenais/anatomia & histologia , Pressão Sanguínea/fisiologia , Imageamento por Ressonância Magnética/métodos , Adulto , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Variações Dependentes do Observador , Projetos Piloto , Análise de Regressão , Reprodutibilidade dos Testes
14.
BMJ Open ; 13(2): e061427, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792332

RESUMO

INTRODUCTION: Public health responses to the COVID-19 pandemic have reaped adverse physical, psychological, social and economic effects, with older adults disproportionally affected. Psychological consequences of the pandemic include fear, worry and anxiety. COVID-19 fear may impact individuals' mitigation behaviours, influencing their willingness to (re)engage in health, social and economic behaviours. This study seeks (1) to develop a robust and evidence-based questionnaire to measure the prevalence of COVID-19 fear among older adults (aged ≥50) in Scotland and (2) to examine the impact of COVID-19 fear on the willingness of older adults to (re)engage across health, social and economic domains as society adjusts to the 'new normal' and inform policy and practice. METHODS AND ANALYSIS: This mixed-method study includes a large-scale multimodal survey, focus groups and interviews with older adults (aged ≥50) living in Scotland, and an email-based 'e-Delphi' consultation with professionals working with older adults. The COVID-19 fear scale was developed and validated using exploratory and confirmatory factor analyses. Survey data will be analysed using descriptive and inferential statistics. Thematic analysis will be used to analyse qualitative data. Survey and qualitative findings will be triangulated and used as the starting point for an 'e-Delphi' consensus consultation with expert stakeholders. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the University of Stirling for multimodal survey development, fieldwork methodology and data management. Anonymised survey data will be deposited with the UK Data Service, with a link provided via the Gateway to Global Ageing. Qualitative data will be deposited with the University of Stirling online digital repository-DataSTORRE. A dedicated work package will oversee dissemination via a coproduced project website, conference presentations, rapid reports and national and international peer-reviewed journal articles. There is planned engagement with Scottish and UK policy makers to contribute to the UK government's COVID-19 recovery strategy.


Assuntos
COVID-19 , Envelhecimento Saudável , Humanos , Idoso , COVID-19/epidemiologia , Pandemias , Escócia/epidemiologia , Envelhecimento
15.
Postepy Kardiol Interwencyjnej ; 19(1): 6-13, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37090217

RESUMO

Introduction: Today, endovascular treatment (EVT) is the therapy of choice for strokes due to acute large vessel occlusion, irrespective of prior thrombolysis. This necessitates fast, coordinated multi-specialty collaboration. Currently, in most countries, the number of physicians and centres with expertise in EVT is limited. Thus, only a small proportion of eligible patients receive this potentially life-saving therapy, often after significant delays. Hence, there is an unmet need to train a sufficient number of physicians and centres in acute stroke intervention in order to allow widespread and timely access to EVT. Aim: To provide multi-specialty training guidelines for competency, accreditation and certification of centres and physicians in EVT for acute large vessel occlusion strokes. Material and methods: The World Federation for Interventional Stroke Treatment (WIST) consists of experts in the field of endovascular stroke treatment. This interdisciplinary working group developed competency - rather than time-based - guidelines for operator training, taking into consideration trainees' previous skillsets and experience. Existing training concepts from mostly single specialty organizations were analysed and incorporated. Results: The WIST establishes an individualized approach to acquiring clinical knowledge and procedural skills to meet the competency requirements for certification of interventionalists of various disciplines and stroke centres in EVT. WIST guidelines encourage acquisition of skills using innovative training methods such as structured supervised high-fidelity simulation and procedural performance on human perfused cadaveric models. Conclusions: WIST multispecialty guidelines outline competency and quality standards for physicians and centres to perform safe and effective EVT. The role of quality control and quality assurance is highlighted.

16.
Cardiovasc Revasc Med ; 53: 67-72, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37012107

RESUMO

INTRODUCTION: Today, endovascular treatment (EVT) is the therapy of choice for strokes due to acute large vessel occlusion, irrespective of prior thrombolysis. This necessitates fast, coordinated multi-specialty collaboration. Currently, in most countries, the number of physicians and centres with expertise in EVT is limited. Thus, only a small proportion of eligible patients receive this potentially life-saving therapy, often after significant delays. Hence, there is an unmet need to train a sufficient number of physicians and centres in acute stroke intervention in order to allow widespread and timely access to EVT. AIM: To provide multi-specialty training guidelines for competency, accreditation and certification of centres and physicians in EVT for acute large vessel occlusion strokes. MATERIAL AND METHODS: The World Federation for Interventional Stroke Treatment (WIST) consists of experts in the field of endovascular stroke treatment. This interdisciplinary working group developed competency - rather than time-based - guidelines for operator training, taking into consideration trainees' previous skillsets and experience. Existing training concepts from mostly single specialty organizations were analysed and incorporated. RESULTS: The WIST establishes an individualized approach to acquiring clinical knowledge and procedural skills to meet the competency requirements for certification of interventionalists of various disciplines and stroke centres in EVT. WIST guidelines encourage acquisition of skills using innovative training methods such as structured supervised high-fidelity simulation and procedural performance on human perfused cadaveric models. CONCLUSIONS: WIST multispecialty guidelines outline competency and quality standards for physicians and centres to perform safe and effective EVT. The role of quality control and quality assurance is highlighted. SUMMARY: The World Federation for Interventional Stroke Treatment (WIST) establishes an individualized approach to acquiring clinical knowledge and procedural skills to meet the competency requirements for certification of interventionalists of various disciplines and stroke centres in endovascular treatment (EVT). WIST guidelines encourage acquisition of skills using innovative training methods such as structured supervised high-fidelity simulation and procedural performance on human perfused cadaveric models. WIST multispecialty guidelines outline competency and quality standards for physicians and centers to perform safe and effective EVT. The role of quality control and quality assurance is highlighted. SIMULTANEOUS PUBLICATION: The WIST 2023 Guidelines are published simultaneously in Europe (Adv Interv Cardiol 2023).


Assuntos
Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Trombectomia/métodos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/métodos , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Cadáver
17.
BMC Fam Pract ; 13: 104, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23067304

RESUMO

BACKGROUND: The Provisional Diagnostic Instrument (PDI-4) is a brief, adult self-report instrument for 4 common psychiatric diagnoses in primary care patients: major depressive episode (MDE), generalized anxiety disorder (GAD), attention deficit hyperactivity disorder (ADHD), and bipolar I disorder based on past or present mania. Our objective was to assess validity of the PDI-4 in a population independent of the study population originally used to develop the scale. METHODS: An online version of the 17-item PDI-4 was administered to 1,047 adults in the US; respondents also completed the PHQ-9, HADS-A, CAARS-S, and MDQ within the online survey. Respondents self-reported diagnosis by a healthcare professional with the terms depression (n=221), anxiety (n=218), attention deficit disorder (n=206), bipolar or manic depressive disorder (n=195), or none of these (n=207). Statistical analyses examined convergent and discriminant validity, and operating characteristics of the PDI-4 relative to the individual, validated, self-rated scales PHQ-9, HADS-A, CAARS-S, and MDQ, for each PDI-4 diagnosis. RESULTS: Convergent validity of the PDI-4 was supported by strong correlations with the corresponding individual scales (range of 0.63 [PDI-4 and MDQ] to 0.87 [PDI-4 and PHQ-9]). Operating characteristics of the PDI-4 were similar to results in the previous site-based study. The scale exhibited moderate sensitivities (0.52 [mania] to 0.70 [ADHD]) and strong specificities (0.86 [mania] to 0.92 [GAD]) using the individual scales as the gold standards. ANOVAs demonstrated that PDI-4 discriminated between subsets of patients defined by pre-specified severity level cutoff scores of the individual scales. However, overlapping symptoms and co-morbidities made differentiation between mental diagnoses much weaker than differentiation from the control group with none of the diagnoses. CONCLUSIONS: The PDI-4 appears to be a suitable, brief, self-rated tool for provisional diagnoses of common mental disorders. However, the high level of symptom overlap between these diagnoses emphasizes that such brief scales are not a replacement for thorough diagnostic evaluation by trained medical providers.


Assuntos
Transtornos de Ansiedade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno Bipolar/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Autorrelato , Sensibilidade e Especificidade , Inquéritos e Questionários
18.
Psychosomatics ; 52(1): 48-55, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21300195

RESUMO

OBJECTIVE: To develop an adult self-report instrument for provisional diagnosis of four common mental disorders in primary care patients. METHODS: Primary care patients were evaluated during routine clinic visits with a self-report screening tool comprised of 85 DSM-IV symptom-based candidate questions. Patients with a physician-assessed provisional diagnosis for generalized anxiety disorder (GAD), major depressive episode (MDE), past/present mania, and adult attention-deficit/hyperactivity disorder (ADHD), or none of these, completed additional self-report clinical questionnaires, and then were interviewed on the telephone by a trained rater for a SCID/ACDS diagnosis. Responses to the symptom-based candidate questions were used to calculate sensitivity and specificity for a SCID/ACDS diagnosis (GAD, N = 24; MDE, N = 89; Mania, N = 24; ADHD, N = 65) and to select the optimal four questions for each diagnosis to be included in the instrument. RESULTS: Analyses resulted in a 17-item instrument for provisional differential diagnosis of GAD, MDE, past/present mania, and ADHD. Comparison of limited symptom-based versus full DSM-IV criteria-based diagnosis showed minimal differences for relative diagnostic accuracy. Sensitivities and specificities, respectively, were 83% and 75% for GAD, 80% and 80% for MDE, 83% and 82% for mania, and 82%and 73% for ADHD. CONCLUSIONS: Based on this preliminary work, the Provisional Diagnostic Instrument-4 is a brief, easily scored, self-report instrument that may assist primary care physicians to identify potential cases of GAD, MDE, past/present mania, and ADHD.


Assuntos
Programas de Rastreamento/instrumentação , Transtornos Mentais/diagnóstico , Atenção Primária à Saúde/métodos , Autorrelato , Inquéritos e Questionários , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Estudos Transversais , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Entrevistas como Assunto , Masculino , Programas de Rastreamento/métodos , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
19.
Psychiatry Res ; 189(3): 475-7, 2011 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-21788083

RESUMO

Single-nucleotide and diplotype associations with 17-item Hamilton Depression Rating Scale (HAMD(17)) total score changes were examined, based on catechol-O-methyltransferase (COMT) rs165599 status in duloxetine-treated, self-identified white patients with major depressive disorder. COMT rs165737 and a diplotype containing COMT rs165599 and COMT rs165737 were associated with HAMD(17) total score changes.


Assuntos
Antidepressivos/uso terapêutico , Catecol O-Metiltransferase/genética , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/genética , Tiofenos/uso terapêutico , Adulto , Cloridrato de Duloxetina , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética , Polimorfismo de Nucleotídeo Único/genética , Escalas de Graduação Psiquiátrica , Fatores Sexuais
20.
Psychiatry Res ; 187(1-2): 74-9, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21095016

RESUMO

UNLABELLED: Dopamine D2 receptors, encoded by DRD2, play a role in regulating serum prolactin concentration. Single nucleotide polymorphisms (SNPs), rs2734842(C), rs6275(T), and rs6279(C) located within DRD2, have been shown to be associated with prolactin increase in olanzapine/fluoxetine combination (OFC)-treated women. The present analyses seek to replicate these results and test other SNPs in DRD2 and neighboring gene ANKK1 for associations with prolactin increase in women, using data from 3 pooled studies of olanzapine, and 2 previously examined studies OFC. An ANCOVA was used to test whether change from baseline in the natural log of prolactin concentration (ln[prolactin]) was associated with SNPs in the pooled olanzapine studies. A meta-analysis was also performed using the inverse chi-square method, pooling p-values from the 2 previously examined studies and the 3 olanzapine studies. Negative strand alleles rs2734842(C), rs6275(T), and rs6279(C) were significantly associated with increased prolactin in olanzapine-treated women, replicating previous results. These SNPs also showed moderate association with increased prolactin in olanzapine-treated and OFC-treated women in the meta-analysis, as did rs4938016, rs2734848, rs2734841, rs1124493, and rs1076562. Five of these SNPs fall in or are adjacent to an LD block spanning DRD2 intron 7, exon 7, 5' untranslated region and ANKK1. CLINICAL TRIAL REGISTRATION: www.clinicaltrial.gov.


Assuntos
Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Prolactina/sangue , Proteínas Serina-Treonina Quinases/genética , Transtornos Psicóticos , Receptores de Dopamina D2/genética , Caracteres Sexuais , Adulto , Análise de Variância , Combinação de Medicamentos , Feminino , Fluoxetina/uso terapêutico , Frequência do Gene , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Metanálise como Assunto , Pessoa de Meia-Idade , Olanzapina , Farmacogenética , Transtornos Psicóticos/sangue , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/genética
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