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1.
J Cardiovasc Electrophysiol ; 33(6): 1262-1271, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524414

RESUMO

AIMS: To investigate the abnormalities of the coronary venous system in candidates for cardiac resynchronization therapy (CRT) and describe methods for circumventing the resulting difficulties. METHODS: From four implanting institutes, data of all CRT implants between October 2008 and October 2020 were screened for abnormal cardiac venous anatomy, defined as an anatomical variation not conforming to the accepted 'normal' anatomy. Patient demographics, procedural detail, and subsequent left ventricle (LV) lead pacing indices were collected. RESULTS: From a total of 3548 CRT implants, 15 (0.42%) patients (80% male) of 72.2 ± 10.6 years in age with an LV ejection fraction of 34 ± 10.3% were identified to have had an abnormal cardiac venous anatomy over the study period. There were 13 cases of persistent left side superior vena cava (pLSVC), five of which had coronary sinus ostium atresia (CSOA) including two with an "unroofed" coronary sinus (CS); one patient had a unique anomalous origin of the CS and one patient had an isolated CSOA. In total 14 patients (60% repeat attempt) had successful percutaneous implant under general anesthesia (46.7%) via the cephalic vein (59.1%), using the femoral approach (53.3%) for levophase venography and/or pull-through, including one case of endocardial LV implant. Pacing follow-up over 37.64 ± 37.6 months demonstrated LV lead threshold between 0.62 and 2.9 volts (pulsewidth 0.4-1.5 ms) in all cases; five patients died within 2.92 ± 1.6 years of a successful implant. CONCLUSION: CRT devices can be implanted percutaneously even in the presence of substantial abnormalities of coronary venous anatomy. Alternative routes of venous access may be required.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Veia Cava Superior Esquerda Persistente , Malformações Vasculares , Terapia de Ressincronização Cardíaca/métodos , Dispositivos de Terapia de Ressincronização Cardíaca , Drenagem , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Masculino , Veia Cava Superior/anormalidades , Veia Cava Superior/diagnóstico por imagem
2.
J Cardiovasc Electrophysiol ; 33(12): 2546-2557, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36284450

RESUMO

INTRODUCTION: The IMPACT study established the role of controlled esophageal cooling in preventing esophageal thermal injury during radiofrequency (RF) ablation for atrial fibrillation (AF). The effect of esophageal cooling on ablation lesion delivery and procedural and patient outcomes had not been previously studied. The objective was to determine the effect of esophageal cooling on the formation of RF lesions, the ability to achieve procedural endpoints, and clinical outcomes. METHODS: Participants in the IMPACT trial underwent AF ablation guided by Ablation Index (30 W at 350-400 AI posteriorly, 40 W at ≥450 AI anteriorly). A blinded 1:1 randomization assigned patients to the use of the ensoETM® device to keep esophageal temperature at 4°C during ablation or standard practice using a single-sensor temperature probe. Ablation parameters and clinical outcomes were analyzed. RESULTS: Procedural data from 188 patients were analyzed. Procedure and fluoroscopy times were similar, and all pulmonary veins were isolated. First-pass pulmonary vein isolation and reconnection at the end of the waiting period were similar in both randomized groups (51/64 vs. 51/68; p = 0.54 and 5/64 vs. 7/68; p = 0.76, respectively). Posterior wall isolation was also similar: 24/33 versus 27/38; p = 0.88. Ablation effect on tissue, measured in impedance drop, was no different between the two randomized groups: 8.6Ω (IQR: 6-11.8) versus 8.76Ω (IQR: 6-12.2; p = 0.25). Arrhythmia recurrence was similar after 12 months (21.1% vs. 24.1%; 95% CI: 0.38-1.84; HR: 0.83; p = 0.66). CONCLUSIONS: Esophageal cooling has been shown to be effective in reducing ablation-related thermal injury during RF ablation. This protection does not compromise standard procedural endpoints or clinical success at 12 months.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Resultado do Tratamento , Átrios do Coração/cirurgia , Ablação por Cateter/métodos , Veias Pulmonares/cirurgia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Recidiva
3.
Europace ; 23(3): 370-379, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33188692

RESUMO

AIMS: Restoring sinus rhythm (SR) by ablation alone is an endpoint used in radiofrequency (RF) ablation for long-standing persistent atrial fibrillation (AF) but not with cryotherapy. The simultaneous use of two cryotherapy catheters can improve ablation efficiency; we compared this with RF ablation in chronic persistent AF aiming for termination to SR by ablation alone. METHODS AND RESULTS: Consecutive patients undergoing their first ablation for persistent AF of >6 months duration were screened. A total of 100 participants were randomized 1:1 to multi-catheter cryotherapy or RF. For cryotherapy, a 28-mm Arctic Front Advance was used in tandem with focal cryoablation catheters. Open-irrigated, non-force sensing catheters were used in the RF group with a 3D mapping system. Pulmonary vein (PV) isolation and non-PV triggers were targeted. Participants were followed up at 6 and 12 months, then yearly. Acute PVI was achieved in all cases. More patients in the multi-catheter cryotherapy group were restored to SR by ablation alone, with a shorter procedure duration. Sinus rhythm continued to the last available follow-up in 16/49 patients (33%) in the multi-catheter at 3.0 ± 1.6 years post-ablation and in 12/50 patients (24%) in the RF group at 4.0 ± 1.2 years post-ablation. The yearly rate of arrhythmia recurrence was similar. CONCLUSION: Multi-catheter cryotherapy can restore SR by ablation alone in more cases and more quickly than RF ablation. Long-term success is difficult to achieve by either methods and is similar with both.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Ablação por Radiofrequência , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Catéteres , Crioterapia , Humanos , Veias Pulmonares/cirurgia , Resultado do Tratamento
4.
Europace ; 23(2): 205-215, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33205201

RESUMO

AIMS: Thermal injury to the oesophagus is an important cause of life-threatening complication after ablation for atrial fibrillation (AF). Thermal protection of the oesophageal lumen by infusing cold liquid reduces thermal injury to a limited extent. We tested the ability of a more powerful method of oesophageal temperature control to reduce the incidence of thermal injury. METHODS AND RESULTS: A single-centre, prospective, double-blinded randomized trial was used to investigate the ability of the ensoETM device to protect the oesophagus from thermal injury. This device was compared in a 1:1 randomization with a control group of standard practice utilizing a single-point temperature probe. In the protected group, the device maintained the luminal temperature at 4°C during radiofrequency (RF) ablation for AF under general anaesthesia. Endoscopic examination was performed at 7 days post-ablation and oesophageal injury was scored. The patient and the endoscopist were blinded to the randomization. We recruited 188 patients, of whom 120 underwent endoscopy. Thermal injury to the mucosa was significantly more common in the control group than in those receiving oesophageal protection (12/60 vs. 2/60; P = 0.008), with a trend toward reduction in gastroparesis (6/60 vs. 2/60, P = 0.27). There was no difference between groups in the duration of RF or in the force applied (P value range= 0.2-0.9). Procedure duration and fluoroscopy duration were similar (P = 0.97, P = 0.91, respectively). CONCLUSION: Thermal protection of the oesophagus significantly reduces ablation-related thermal injury compared with standard care. This method of oesophageal protection is safe and does not compromise the efficacy or efficiency of the ablation procedure.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Esôfago/cirurgia , Humanos , Estudos Prospectivos , Temperatura , Resultado do Tratamento
5.
Pacing Clin Electrophysiol ; 44(4): 614-624, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33624296

RESUMO

BACKGROUND: Cardiac implantable electronic device (CIED)-related perforation is uncommon but potentially lethal. Management typically includes the use of computed tomography (CT) scanning and often involves cardiac surgery. METHODS: Patients presenting to a single referral centre with CIED-related cardiac perforation between 2013 and 2019 were identified. Demographics, diagnostic modalities, the method of lead revision, and 30-day complications were examined. RESULTS: A total of 46 cases were identified; median time from implantation to diagnosis was 14 days (interquartile range = 4-50). Most were females (29/46, 63%), 9/46 (20%) had cancer, 18 patients (39%) used oral anticoagulants, and no patients had prior cardiac surgery. Active fixation was involved in 98% of cases; 9% involved an implantable cardioverter defibrillator lead. Thirty-seven leads perforated the right ventricle (apex: 24) and 9 punctured the right atrium (lateral wall: 5). Abnormal electrical parameters were noted in 95% of interrogated cases. Perforation was visualized in 41% and 6% of cases with chest X-ray (CXR) and transthoracic echocardiography, respectively. CXR revealed a perforation, gross lead displacement, or left-sided pleural effusion in 74% of cases. Pericardial effusion occurred in 26 patients (57%) of whom 11 (24%) developed tamponade, successfully drained percutaneously. Pre-extraction CT scan was performed in 19 patients but was essential in four cases. Transvenous lead revision (TLR) was successfully performed in all cases with original leads repositioned in six patients, without recourse to surgery. Thirty-day mortality and complications were low (0% and 26%, respectively). CONCLUSION: CT scanning provides incremental diagnostic value in a minority of CIED-related perforations. TLR is a safe and effective strategy.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Traumatismos Cardíacos/diagnóstico por imagem , Traumatismos Cardíacos/cirurgia , Tomografia Computadorizada por Raios X , Idoso , Remoção de Dispositivo , Ecocardiografia , Feminino , Traumatismos Cardíacos/etiologia , Humanos , Masculino , Estudos Prospectivos , Reoperação , Fatores de Risco
6.
Molecules ; 25(16)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796601

RESUMO

Urinary volatile compounds (VCs) have been recently assessed for disease diagnoses. They belong to very diverse chemical classes, and they are characterized by different volatilities, polarities and concentrations, complicating their analysis via a single analytical procedure. There remains a need for better, lower-cost methods for VC biomarker discovery. Thus, there is a strong need for alternative methods, enabling the detection of a broader range of VCs. Therefore, the main aim of this study was to optimize a simple and reliable liquid-liquid extraction (LLE) procedure for the analysis of VCs in urine using gas chromatography-mass spectrometry (GC-MS), in order to obtain the maximum number of responses. Extraction parameters such as pH, type of solvent and ionic strength were optimized. Moreover, the same extracts were analyzed using Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), to evaluate the applicability of a single urine extraction for multiplatform purposes. After the evaluation of experimental conditions, an LLE protocol using 2 mL of urine in the presence of 2 mL of 1 M sulfuric acid and sodium sulphate extracted with dichloromethane was found to be optimal. The optimized method was validated with the external standards and was found to be precise and linear, and allowed for detection of >400 peaks in a single run present in at least 50% of six samples-considerably more than the number of peaks detected by solid-phase microextracton fiber pre-concentration-GC-MS (328 ± 6 vs. 234 ± 4). 1H-NMR spectroscopy of the polar and non-polar extracts extended the range to >40 more (mainly low volatility compounds) metabolites (non-destructively), the majority of which were different from GC-MS. The more peaks detectable, the greater the opportunity of assessing a fingerprint of several compounds to aid biomarker discovery. In summary, we have successfully demonstrated the potential of LLE as a cheap and simple alternative for the analysis of VCs in urine, and for the first time the applicability of a single urine solvent extraction procedure for detecting a wide range of analytes using both GC-MS and 1H-NMR analysis to enhance putative biomarker detection. The proposed method will simplify the transport between laboratories and storage of samples, as compared to intact urine samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração Líquido-Líquido/métodos , Extração Líquido-Líquido/normas , Espectroscopia de Prótons por Ressonância Magnética/métodos , Urinálise/métodos , Compostos Orgânicos Voláteis/urina , Feminino , Humanos
7.
Nature ; 504(7480): 437-40, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24226772

RESUMO

Glucose homeostasis is a vital and complex process, and its disruption can cause hyperglycaemia and type II diabetes mellitus. Glucokinase (GK), a key enzyme that regulates glucose homeostasis, converts glucose to glucose-6-phosphate in pancreatic ß-cells, liver hepatocytes, specific hypothalamic neurons, and gut enterocytes. In hepatocytes, GK regulates glucose uptake and glycogen synthesis, suppresses glucose production, and is subject to the endogenous inhibitor GK regulatory protein (GKRP). During fasting, GKRP binds, inactivates and sequesters GK in the nucleus, which removes GK from the gluconeogenic process and prevents a futile cycle of glucose phosphorylation. Compounds that directly hyperactivate GK (GK activators) lower blood glucose levels and are being evaluated clinically as potential therapeutics for the treatment of type II diabetes mellitus. However, initial reports indicate that an increased risk of hypoglycaemia is associated with some GK activators. To mitigate the risk of hypoglycaemia, we sought to increase GK activity by blocking GKRP. Here we describe the identification of two potent small-molecule GK-GKRP disruptors (AMG-1694 and AMG-3969) that normalized blood glucose levels in several rodent models of diabetes. These compounds potently reversed the inhibitory effect of GKRP on GK activity and promoted GK translocation both in vitro (isolated hepatocytes) and in vivo (liver). A co-crystal structure of full-length human GKRP in complex with AMG-1694 revealed a previously unknown binding pocket in GKRP distinct from that of the phosphofructose-binding site. Furthermore, with AMG-1694 and AMG-3969 (but not GK activators), blood glucose lowering was restricted to diabetic and not normoglycaemic animals. These findings exploit a new cellular mechanism for lowering blood glucose levels with reduced potential for hypoglycaemic risk in patients with type II diabetes mellitus.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal , Animais , Glicemia/metabolismo , Proteínas de Transporte/metabolismo , Núcleo Celular/enzimologia , Cristalografia por Raios X , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/enzimologia , Modelos Animais de Doenças , Hepatócitos , Humanos , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Hiperglicemia/enzimologia , Hipoglicemiantes/química , Fígado/citologia , Fígado/enzimologia , Fígado/metabolismo , Masculino , Modelos Moleculares , Especificidade de Órgãos , Fosforilação/efeitos dos fármacos , Piperazinas/química , Piperazinas/metabolismo , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Wistar , Sulfonamidas/química , Sulfonamidas/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
8.
Sleep Breath ; 23(4): 1245-1254, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30825066

RESUMO

PURPOSE: Polysomnography is not recommended for children at home and does not adequately capture partial upper airway obstruction (snoring and stertor), the dominant pathology in pediatric sleep-disordered breathing. New methods are required for assessment. Aims were to assess sleep disruption linked to partial upper airway obstruction and to evaluate unattended Sonomat use in a large group of children at home. METHODS: Children with suspected obstructive sleep apnea (OSA) had a single home-based Sonomat recording (n = 231). Quantification of breath sound recordings allowed identification of snoring, stertor, and apneas/hypopneas. Movement signals were used to measure quiescent (sleep) time and sleep disruption. RESULTS: Successful recordings occurred in 213 (92%) and 113 (53%) had no OSA whereas only 11 (5%) had no partial obstruction. Snore/stertor occurred more frequently (15.3 [5.4, 30.1] events/h) and for a longer total duration (69.9 min [15.7, 140.9]) than obstructive/mixed apneas and hypopneas (0.8 [0.0, 4.7] events/h, 1.2 min [0.0, 8.5]); both p < 0.0001. Many non-OSA children had more partial obstruction than those with OSA. Most intervals between snore and stertor runs were < 60 s (79% and 61% respectively), indicating that they occur in clusters. Of 14,145 respiratory-induced movement arousals, 70% were preceded by runs of snore/stertor with the remainder associated with apneas/hypopneas. CONCLUSIONS: Runs of snoring and stertor occur much more frequently than obstructive apneas/hypopneas and are associated with a greater degree of sleep disruption. Children with and without OSA are frequently indistinguishable regarding the amount, frequency, and the degree of sleep disturbance caused by snoring and stertor.


Assuntos
Polissonografia , Apneia Obstrutiva do Sono/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Ronco/epidemiologia , Criança , Correlação de Dados , Estudos Transversais , Humanos , Reprodutibilidade dos Testes , Apneia Obstrutiva do Sono/diagnóstico , Transtornos do Sono-Vigília/diagnóstico , Ronco/diagnóstico
9.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959740

RESUMO

The concentration of volatile organic compounds (VOCs) can inform about the metabolic condition of the body. In the small intestine of untreated persons with celiac disease (CD), chronic inflammation can occur, leading to nutritional deficiencies, and consequently to functional impairments of the whole body. Metabolomic studies showed differences in the profile of VOCs in biological fluids of patients with CD in comparison to healthy persons; however, there is scarce quantitative and nutritional intervention information. The aim of this study was to evaluate the effect of the supplementation of a gluten-free diet (GFD) with prebiotic oligofructose-enriched inulin (Synergy 1) on the concentration of VOCs in the urine of children and adolescents with CD. Twenty-three participants were randomized to the group receiving Synergy 1 (10 g per day) or placebo for 12 weeks. Urinary VOCs were analyzed using solid-phase microextraction and gas chromatography⁻mass spectrometry. Sixteen compounds were identified and quantified in urine samples. The supplementation of GFD with Synergy 1 resulted in an average concentration drop (36%) of benzaldehyde in urine samples. In summary, Synergy 1, applied as a supplement of GFD for 12 weeks had a moderate impact on the VOC concentrations in the urine of children with CD.


Assuntos
Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Inulina/administração & dosagem , Oligossacarídeos/administração & dosagem , Adolescente , Doença Celíaca/patologia , Doença Celíaca/urina , Criança , Pré-Escolar , Cromatografia Gasosa , Sinergismo Farmacológico , Feminino , Humanos , Inulina/urina , Masculino , Espectrometria de Massas , Oligossacarídeos/urina , Placebos , Prebióticos/administração & dosagem , Compostos Orgânicos Voláteis/administração & dosagem , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/urina
10.
Europace ; 19(8): 1317-1321, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27702870

RESUMO

AIM: The Biosense Webster ThermoCool® SmartTouch® Surround Flow (STSF) catheter is a recently developed ablation catheter incorporating Surround Flow (SF) technology to ensure efficient cooling and force sensing to quantify tissue contact. In our unit, it superseded the ThermoCool® SF catheter from the time of its introduction in May 2015. METHODS AND RESULTS: Procedure-related data were collected prospectively for the first 100 ablation procedures performed in our department using the STSF catheter. From a database of 654 procedures performed in our unit using the SF catheter, we selected one to match each STSF procedure, matching for procedure type, operator experience, patient age, and gender. The groups were well matched for patient age, gender, and procedure type. Procedure duration was similar in both groups (mean 225.5 vs. 221.4 min, IQR 106.5 vs. 91.5, P = 0.55), but fluoroscopy duration was shorter in the STSF group (mean 25.8 vs. 30.0, IQR 19.6 vs. 18.5, P = 0.03). No complication occurred in the STSF group. Complications occurred in two cases in the SF group (one pericardial effusion requiring drainage and one need for permanent pacing). Complete procedural success was achieved in 98 cases in the STSF group and 94 cases in the SF group (P = 0.15). The composite endpoint of procedure failure or acute complication was less common in the STSF group (2 vs. 8, P = 0.05). CONCLUSION: The STSF catheter is safe and effective in treating a range of arrhythmias. Compared with the SF catheter, it shows a trend towards improved safety-efficacy balance.


Assuntos
Arritmias Cardíacas/cirurgia , Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Ablação por Cateter/instrumentação , Irrigação Terapêutica/instrumentação , Transdutores de Pressão , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Cateterismo Cardíaco/efeitos adversos , Ablação por Cateter/efeitos adversos , Bases de Dados Factuais , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Irrigação Terapêutica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
11.
J Proteome Res ; 15(9): 3284-97, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27427999

RESUMO

This study provides comprehensive proteomic profiles from the venom producing posterior salivary glands of octopus (superorder Octopodiformes) species. A combined transcriptomic and proteomic approach was used to identify 1703 proteins from the posterior salivary gland of the southern blue-ringed octopus, Hapalochlaena maculosa and 1300 proteins from the posterior salivary gland of the southern sand octopus, Octopus kaurna. The two proteomes were broadly similar; clustering of proteins into orthogroups revealed 937 that were shared between species. Serine proteases were particularly diverse and abundant in both species. Other abundant proteins included a large number of secreted proteins, many of which had no known conserved domains, or homology to proteins with known function. On the basis of homology to known venom proteins, 23 putative toxins were identified in H. maculosa and 24 in O. kaurna. These toxins span nine protein families: CAP (cysteine rich secretory proteins, antigen 5, parthenogenesis related), chitinase, carboxylesterase, DNase, hyaluronidase, metalloprotease, phospholipase, serine protease and tachykinin. Serine proteases were responsible for 70.9% and 86.3% of putative toxin expression in H. maculosa and O. kaurna, respectively, as determined using intensity based absolute quantification (iBAQ) measurements. Phylogenetic analysis of the putative toxin serine proteases revealed a similar suite of diverse proteins present in both species. Posterior salivary gland composition of H. maculosa and O. kaurna differ in several key aspects. While O. kaurna expressed the proteinaceous neurotoxin, tachykinin, this was absent from H. maculosa, perhaps reflecting the acquisition of a potent nonproteinaceous neurotoxin, tetrodotoxin (TTX) produced by bacteria in the salivary glands of that species. The dispersal factor, hyaluronidase was particularly abundant in H. maculosa. Chitinase was abundant in both species and is believed to facilitate envenomation in chitinous prey such as crustaceans. Cephalopods represent a largely unexplored source of novel proteins distinct from all other venomous taxa and are of interest for further inquiry, as novel proteinaceous toxins derived from venoms may contribute to pharmaceutical design.


Assuntos
Octopodiformes/química , Proteômica , Glândulas Salivares/química , Transcriptoma , Animais , Análise por Conglomerados , Toxinas Marinhas/análise , Serina Proteases/análise , Especificidade da Espécie , Peçonhas/enzimologia
12.
Bioorg Med Chem ; 24(10): 2215-34, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27085672

RESUMO

One of the challenges for targeting B-Raf(V600E) with small molecule inhibitors had been achieving adequate selectivity over the wild-type protein B-Raf(WT), as inhibition of the latter has been associated with hyperplasia in normal tissues. Recent studies suggest that B-Raf inhibitors inducing the 'DFG-in/αC-helix-out' conformation (Type IIB) likely will exhibit improved selectivity for B-Raf(V600E). To explore this hypothesis, we transformed Type IIA inhibitor (1) into a series of Type IIB inhibitors (sulfonamides and sulfamides 4-6) and examined the SAR. Three selectivity indices were introduced to facilitate the analyses: the B-Raf(V600E)/B-Raf(WT) biochemical ((b)S), cellular ((c)S) selectivity, and the phospho-ERK activation ((p)A). Our data indicates that α-branched sulfonamides and sulfamides show higher selectivities than the linear derivatives. We rationalized this finding based on analysis of structural information from the literature and provided evidence for a monomeric B-Raf-inhibitor complex previously hypothesized to be responsible for the desired B-Raf(V600E) selectivity.


Assuntos
Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Purinas/química , Purinas/farmacologia , Piridinas/química , Piridinas/farmacologia , Aminação , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Modelos Moleculares , Mutação Puntual , Conformação Proteica em alfa-Hélice/efeitos dos fármacos , Proteínas Proto-Oncogênicas B-raf/química , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Relação Estrutura-Atividade
13.
Bioorg Med Chem Lett ; 25(19): 4136-42, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26298499

RESUMO

Based on lead compound 1, which was discovered from a high-throughput screen, a series of PI3Kα/mTOR inhibitors were evaluated that contained an imidazo[1,2-a]pyridine as a core replacement for the benzimidazole contained in 1. By exploring various ring systems that occupy the affinity pocket, two fragments containing a methoxypyridine were identified that gave <100 nM potency toward PI3Kα in enzyme and cellular assays with moderate stability in rat and human liver microsomes. With the two methoxypyridine groups selected to occupy the affinity pocket, analogs were prepared with various fragments intended to occupy the ribose pocket of PI3Kα and mTOR. From these analogs, tertiary alcohol 18 was chosen for in vivo pharmacodynamic evaluation based on its potency in the PI3Kα cellular assay, microsomal stability, and in vivo pharmacokinetic properties. In a mouse liver pharmacodynamic assay, compound 18 showed 56% inhibition of HFG-induced AKT (Ser473) phosphorylation at a 30 mg/kg dose.


Assuntos
Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Piridinas/química , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Camundongos , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/síntese química , Ratos , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismo
14.
J Cell Sci ; 125(Pt 1): 59-66, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22250205

RESUMO

In Drosophila, normal and transformed cells compete with each other for survival in a process called cell competition. However, it is not known whether comparable phenomena also occur in mammals. Scribble is a tumor suppressor protein in Drosophila and mammals. In this study we examine the interface between normal and Scribble-knockdown epithelial cells using Madin-Darby Canine Kidney (MDCK) cells expressing Scribble short hairpin RNA (shRNA) in a tetracycline-inducible manner. We observe that Scribble-knockdown cells undergo apoptosis and are apically extruded from the epithelium when surrounded by normal cells. Apoptosis does not occur when Scribble-knockdown cells are cultured alone, suggesting that the presence of surrounding normal cells induces the cell death. We also show that death of Scribble-knockdown cells occurs independently of apical extrusion. Finally, we demonstrate that apoptosis of Scribble-knockdown cells depends on activation of p38 mitogen-activated protein kinase (MAPK). This is the first demonstration that an oncogenic transformation within an epithelium induces cell competition in a mammalian cell culture system.


Assuntos
Proteínas de Drosophila , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Proteínas de Membrana/deficiência , Proteínas de Membrana/metabolismo , Animais , Apoptose , Linhagem Celular , Polaridade Celular , Forma Celular , Cães , Ativação Enzimática , Técnicas de Silenciamento de Genes , Proteínas de Membrana/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
J Cardiovasc Electrophysiol ; 25(7): 714-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24641352

RESUMO

INTRODUCTION: Pulmonary vein isolation (PVI) and cavotricuspid isthmus (CTI) ablation are often performed as part of the same procedure. In many cases, PVI is performed by cryotherapy and then CTI ablation by radiofrequency (RF) energy. We sought to determine whether it is more efficient to perform CTI ablation simultaneously with PVI using separate cryogenerators. METHODS AND RESULTS: We performed cryoablation of the CTI during PVI with the Arctic Front cryoballoon in 25 consecutive patients with clinical indications for both (PVI/CTI-cryo group). Procedural data were compared to those of 25 matched patients who underwent PVI only by the same operator (PVI-only group), and 25 patients who underwent PVI by cryotherapy and CTI ablation using RF energy sequentially during the same procedure (PVI/CTI-mixed group). No complication occurred. All veins were isolated; bidirectional CTI block was demonstrated in all cases where it was attempted, except for 1 patient in the PVI/CTI-mixed group. Procedure and fluoroscopy duration were significantly shorter in the PVI/CTI-cryo group (162 ± 34 and 24 ± 5 minutes) than in the PVI/CTI-mixed group (209 ± 46 minutes, P < 0.001 and 59 ± 28 minutes, P < 0.001). Procedure and fluoroscopy duration in the PVI-only group (155 ± 32 and 22 ± 8 minutes) were similar to those in the PVI/CTI-cryo group (P = NS) but significantly shorter than in the PVI/CTI-mixed group (P < 0.001 for both). Clinical outcomes were similar in all groups. CONCLUSION: When CTI ablation is performed with RF energy after PVI by cryoballoon, it adds significantly to the procedure and fluoroscopy durations; when performed contemporaneously using cryotherapy at both sites, the procedure and fluoroscopy durations are not prolonged.


Assuntos
Fibrilação Atrial/cirurgia , Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Crioterapia , Veias Pulmonares/cirurgia , Valva Tricúspide/cirurgia , Veias Cavas/cirurgia , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Flutter Atrial/diagnóstico , Flutter Atrial/fisiopatologia , Cateteres Cardíacos , Ablação por Cateter/efeitos adversos , Ablação por Cateter/instrumentação , Crioterapia/efeitos adversos , Crioterapia/instrumentação , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Veias Pulmonares/fisiopatologia , Radiografia Intervencionista , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Valva Tricúspide/fisiopatologia , Veias Cavas/fisiopatologia
16.
Bioorg Med Chem Lett ; 24(24): 5630-5634, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466188

RESUMO

Replacement of the piperazine sulfonamide portion of the PI3Kα inhibitor AMG 511 (1) with a range of aliphatic alcohols led to the identification of a truncated gem-dimethylbenzylic alcohol analog, 2-(5-(4-amino-6-methyl-1,3,5-triazin-2-yl)-6-((5-fluoro-6-methoxypyridin-3-yl)amino)pyridin-3-yl)propan-2-ol (7). This compound possessed good in vitro efficacy and pharmacokinetic parameters and demonstrated an EC50 of 239 ng/mL in a mouse liver pharmacodynamic model measuring the inhibition of hepatocyte growth factor (HGF)-induced Akt Ser473 phosphorylation in CD1 nude mice 6 h post-oral dosing.


Assuntos
Álcoois/química , Inibidores de Fosfoinositídeo-3 Quinase , Piperazinas/química , Inibidores de Proteínas Quinases/química , Piridinas/síntese química , Sulfonamidas/química , Triazinas/síntese química , Animais , Feminino , Meia-Vida , Fígado/metabolismo , Masculino , Camundongos , Camundongos Nus , Conformação Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Piperazina , Piperazinas/metabolismo , Piperazinas/farmacocinética , Ligação Proteica , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridinas/metabolismo , Piridinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/metabolismo , Sulfonamidas/farmacocinética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Triazinas/metabolismo , Triazinas/farmacocinética
17.
BMJ Open ; 14(1): e075792, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38296285

RESUMO

OBJECTIVE: To develop an international consensus statement to advise on designing, delivering and evaluating sport-based interventions (SBIs) aimed at promoting social, psychological and physical well-being in prison. DESIGN: Modified Delphi using two rounds of survey questionnaires and two consensus workshops. PARTICIPANTS: A multidisciplinary panel of more than 40 experts from 15 international jurisdictions was formed, including representation from the following groups and stakeholders: professionals working in the justice system; officials from sport federations and organisations; academics with research experience of prisons, secure forensic mental health settings and SBIs; and policy-makers in criminal justice and sport. RESULTS: A core research team and advisory board developed the initial rationale, statement and survey. This survey produced qualitative data which was analysed thematically. The findings were presented at an in-person workshop. Panellists discussed the findings, and, using a modified nominal group technique, reached a consensus on objectives to be included in a revised statement. The core research team and advisory board revised the statement and recirculated it with a second survey. Findings from the second survey were discussed at a second, virtual, workshop. The core research team and advisory board further revised the consensus statement and recirculated it asking panellists for further comments. This iterative process resulted in seven final statement items; all participants have confirmed that they agreed with the content, objectives and recommendations of the final statement. CONCLUSIONS: The statement can be used to assist those that design, deliver and evaluate SBIs by providing guidance on: (1) minimum levels of competence for those designing and delivering SBIs; (2) the design and delivery of inclusive programmes prioritising disadvantaged groups; and (3) evaluation measures which are carefully calibrated both to capture proposed programme outcomes and to advance an understanding of the systems, processes and experiences of sport engagement in prison.


Assuntos
Prisões , Esportes , Humanos , Consenso , Inquéritos e Questionários , Técnica Delphi
18.
Proc Biol Sci ; 280(1759): 20130273, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23516246

RESUMO

Despite its charismatic appeal to both scientists and the general public, remarkably little is known about the giant squid Architeuthis, one of the largest of the invertebrates. Although specimens of Architeuthis are becoming more readily available owing to the advancement of deep-sea fishing techniques, considerable controversy exists with regard to topics as varied as their taxonomy, biology and even behaviour. In this study, we have characterized the mitochondrial genome (mitogenome) diversity of 43 Architeuthis samples collected from across the range of the species, in order to use genetic information to provide new and otherwise difficult to obtain insights into the life of this animal. The results show no detectable phylogenetic structure at the mitochondrial level and, furthermore, that the level of nucleotide diversity is exceptionally low. These observations are consistent with the hypotheses that there is only one global species of giant squid, Architeuthis dux (Steenstrup, 1857), and that it is highly vagile, possibly dispersing through both a drifting paralarval stage and migration of larger individuals. Demographic history analyses of the genetic data suggest that there has been a recent population expansion or selective sweep, which may explain the low level of genetic diversity.


Assuntos
Decapodiformes/genética , Variação Genética , Genoma Mitocondrial , Animais , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Decapodiformes/classificação , Feminino , Masculino , Dados de Sequência Molecular , Filogenia , Filogeografia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência
19.
PLoS Biol ; 8(7): e1000422, 2010 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-20644714

RESUMO

During the initial stages of carcinogenesis, transformation events occur in a single cell within an epithelial monolayer. However, it remains unknown what happens at the interface between normal and transformed epithelial cells during this process. In Drosophila, it has been recently shown that normal and transformed cells compete with each other for survival in an epithelial tissue; however the molecular mechanisms whereby "loser cells" undergo apoptosis are not clearly understood. Lgl (lethal giant larvae) is a tumor suppressor protein and plays a crucial role in oncogenesis in flies and mammals. Here we have examined the involvement of Lgl in cell competition and shown that a novel Lgl-binding protein is involved in Lgl-mediated cell competition. Using biochemical immunoprecipitation methods, we first identified Mahjong as a novel binding partner of Lgl in both flies and mammals. In Drosophila, Mahjong is an essential gene, but zygotic mahjong mutants (mahj(-/-)) do not have obvious patterning defects during embryonic or larval development. However, mahj(-/-) cells undergo apoptosis when surrounded by wild-type cells in the wing disc epithelium. Importantly, comparable phenomena also occur in Mahjong-knockdown mammalian cells; Mahjong-knockdown Madin-Darby canine kidney epithelial cells undergo apoptosis, only when surrounded by non-transformed cells. Similarly, apoptosis of lgl(-/-) cells is induced when they are surrounded by wild-type cells in Drosophila wing discs. Phosphorylation of the c-Jun N-terminal kinase (JNK) is increased in mahj(-/-) or lgl(-/-) mutant cells, and expression of Puckered (Puc), an inhibitor of the JNK pathway, suppresses apoptosis of these mutant cells surrounded by wild-type cells, suggesting that the JNK pathway is involved in mahj- or lgl-mediated cell competition. Finally, we have shown that overexpression of Mahj in lgl(-/-) cells strongly suppresses JNK activation and blocks apoptosis of lgl(-/-) cells in the wild-type wing disc epithelium. These data indicate that Mahjong interacts with Lgl biochemically and genetically and that Mahjong and Lgl function in the same pathway to regulate cellular competitiveness. As far as we are aware, this is the first report that cell competition can occur in a mammalian cell culture system.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose , Linhagem Celular , Células Clonais , Cães , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Epitélio/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Ligação Proteica , Proteínas Serina-Treonina Quinases , Ubiquitina-Proteína Ligases , Asas de Animais/citologia , Asas de Animais/metabolismo
20.
Biol Lett ; 9(4): 20130192, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-23740295

RESUMO

An individual's gametes can represent a nourishing food source for a manipulative mate. Here, we provide evidence of ejaculate and sperm consumption in a cephalopod. Through labelling male spermatophores with (14)C radiolabel, we found that female squid, Sepiadarium austrinum, consumed the spermatophores of their partners and directed the nutrients received into both somatic maintenance and egg production. We further show that in this species-where fertilization occurs externally in the female's buccal cavity-sperm storage is short-term (less than 21 days). The combination of female spermatophore consumption and short-term external sperm storage has the potential to exert strong selection on male ejaculates and reproductive strategies.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Decapodiformes/fisiologia , Comportamento Sexual Animal , Animais , Comportamento Alimentar , Feminino , Fertilização , Masculino , Reprodução , Espermatogônias , Espermatozoides , Fatores de Tempo , Vitória
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