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1.
Curr Oncol Rep ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869667

RESUMO

PURPOSE OF REVIEW: This article aims to illustrate the current state of investigations and management of liver metastases in patients with Neuroendocrine Neoplasms. Neuroendocrine tumours (NETs) are rising in incidence globally and have become the second most prevalent gastrointestinal malignancy in UK and USA. Frequently, patients have metastatic disease at time of presentation. The liver is the most common site of metastases for gastro-enteropancreatic NETs. Characterisation of liver metastases with imaging is important to ensure disease is not under-staged. RECENT FINDINGS: Magnetic resonance imaging and positron emission tomography are now becoming standard of care for imaging liver metastases. There is an increasing armamentarium of therapies available for management of NETs and loco-regional therapy for liver metastases. The data supporting surgical and loco-regional therapy is reviewed with focus on role of liver transplantation. It is important to use appropriate imaging and classification of NET liver metastases. It is key that decisions regarding approach to treatment is undertaken in a multidisciplinary team and that individualised approaches are considered for management of patients with metastatic NETs.

2.
Diagn Interv Radiol ; 27(5): 677-683, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34318754

RESUMO

Colorectal cancer liver metastases (CRLMs) are common. Treating CRLMs with thermal ablation can prolong survival, but compared to lesions smaller than 3 cm, local control rates and overall survival are relatively worse with larger, intermediate (3-5 cm) lesions. Local recurrence rates range between 1.7%-20.2% and 6.7%-68.9% for CRLMs less than 3 cm and greater than 3 cm, respectively. Worse outcomes are also present when ablating intermediate size hepatocellular carcinoma (HCC) and there are some pathological similarities with CRLMs, namely the presence of micrometastatic disease. Combining ablation with transarterial chemoembolization is more effective in treating intermediate-size HCC than ablation alone. A meta-analysis of robust randomized controlled trials demonstrated long-term improved survival with combination therapy compared to ablation alone (odds ratio at 1, 3 and 5 years of 2.74, 2.77 and 5.23, respectively). There is, however, minimal evidence for combination therapy in CRLMs, limited to a handful of studies that are predominantly retrospective and have heterogeneous inclusion criteria. Given the difficulty in successfully treating intermediate CRLMs, the strong evidence for combination therapy in intermediate HCC and potential pathological similarities, formal evaluation of combination treatment in CRLM is merited. This review highlights existing evidence for treatment of intermediate-size liver lesions and highlights where trials in CRLMs should focus.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Quimioembolização Terapêutica , Neoplasias Colorretais , Neoplasias Hepáticas , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia , Estudos Retrospectivos , Resultado do Tratamento
5.
Br J Radiol ; 94(1118): 20200854, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32960674

RESUMO

Renal cryoablation is a treatment option for early stage renal cell carcinomas with excellent oncological outcomes and low morbidity. This review outlines the technique of renal cryoablation and provides a guide for interventional radiologists on setting up an integrated service within a renal cancer network multidisciplinary setting. Patient selection and preparation, together with the technical aspects which ensure optimal oncological outcomes and avoid collateral damage to adjacent organs are highlighted.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Radiologia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Criocirurgia , Humanos , Rim/diagnóstico por imagem , Rim/cirurgia
6.
AJR Am J Roentgenol ; 215(1): 242-247, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32286877

RESUMO

OBJECTIVE. The purpose of this study was to evaluate the immediate and 3- and 5-year outcomes of patients with clinical stage T1 (cT1) biopsy-proven renal cell carcinoma (RCC) treated by image-guided percutaneous cryoablation at a regional interventional oncology center. MATERIALS AND METHODS. A prospectively maintained local interventional radiology database identified patients with cT1 RCC lesions that were treated by percutaneous cryoablation. Technical success, procedural complications (graded using the Clavien-Dindo classification system), and the residual unablated tumor rate were collated. Local tumor progression-free survival was estimated using Kaplan-Meier estimates. RESULTS. A total of 180 patients with 185 separate cT1 RCC lesions were identified. Mean patient age was 68.4 years (range, 34.1-88.9 years) and 52 patients (28.9%) were women. There were 168 (90.8%) and 17 (9.2%) cT1a and cT1b lesions, respectively, with a mean lesion size of 28.5 mm (range, 11-58 mm). Technical success was achieved in 183 of 185 (98.9%) patients. The major complication rate (Clavien-Dindo classification ≥ grade III) was 2.2% (four out of 185). Residual unablated tumor on the first follow-up scan was identified in four of 183 tumors (2.2%). Estimated local tumor progression-free survival at 3 and 5 years was 98.3% and 94.9%, respectively. No distant metastases or deaths attributable to RCC occurred. Mean estimated glomerular filtration rate (eGFR) before the procedure was 72.4 ± 18.5 (SD) mL/min/1.73 m2 and this was not statistically significantly different after the procedure (69.7 ± 18.8 mL/min/1.73 m2), at 1 year (70.7 ± 16.4 mL/min/1.73 m2), or at 2 years (69.8 ± 18.9 mL/min/1.73 m2) (p > 0.05). CONCLUSION. These data add to the accumulating evidence that image-guided cryoablation is an efficacious treatment for selected cT1 RCC with a low complication rate and ro bust 3- and 5-year outcomes.


Assuntos
Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Criocirurgia/métodos , Neoplasias Renais/cirurgia , Radiografia Intervencionista , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Taxa de Filtração Glomerular , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/patologia , Londres , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias/classificação , Estudos Retrospectivos
7.
Ultrasound ; 28(1): 54-57, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32063996

RESUMO

INTRODUCTION: Splenogonadal fusion is a rare developmental disorder that results in a gonadal or paragonadal mass due to the close proximity of the developing spleen and gonad. CASE REPORT: We describe a case of splenogonadal fusion presenting as a paratesticular mass in a 25-year-old male. This was ultimately diagnosed on surgical biopsy. DISCUSSION: Splenogonadal fusion is a rare abnormality but can be managed conservatively. The sonographic features and the differential diagnosis are highlighted. CONCLUSION: Through this case, we highlight the clinical and sonographic features of splenogonadal fusion. Awareness amongst ultrasound practitioners is important, given that it can be managed conservatively, and means of a non-invasive diagnosis are highlighted.

9.
Behav Brain Res ; 360: 270-278, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30543903

RESUMO

The 5-HT7 receptor is the most recently identified receptor subtype within a family of 5-HT receptors activated by the neurotransmitter serotonin. There has been significant interest in investigating the potential role of this receptor in psychiatric disorders including depression, anxiety, and schizophrenia. Behaviors of 5-HT7 +/+ (wild-type or WT) and 5-HT7 -/- (receptor knockout or KO) mice were compared across 10 different assays (7 for anxiety, 1 for depression, 2 for psychosis) to identify differences that could indicate clinical potential for 5-HT7 receptor antagonism. Evaluation of KO vs. WT mice demonstrated significant differences between the genotypes in the fear conditioning, shock-probe burying, novelty-suppressed feeding, punishment memory, forced swim test, and d-amphetamine hyperactivity assays. There was not consistency in either the direction of behavioral effects across genotypes or across assays. Thus, data from these behavioral assays did not uniformly support the idea that 5-HT7 receptors constitute an important drug target for these psychiatric disorders. The present findings are generally congruent with the mixed results in the literature on the behaviors of 5-HT7 -/-mice and with the data on effects of 5-HT7 receptor antagonists in rodent models that detect activity of anxiolytic, antidepressant, and antipsychotic effects.


Assuntos
Ansiedade/tratamento farmacológico , Depressão/tratamento farmacológico , Receptores de Serotonina/deficiência , Esquizofrenia/tratamento farmacológico , Antagonistas da Serotonina/uso terapêutico , Animais , Condicionamento Operante/efeitos dos fármacos , Modelos Animais de Doenças , Estimulação Elétrica , Comportamento Exploratório/efeitos dos fármacos , Medo/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Febre/etiologia , Febre/terapia , Locomoção/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Knockout , Punição , Receptores de Serotonina/genética , Reforço Psicológico , Estresse Psicológico/complicações , Natação/psicologia
10.
ACS Med Chem Lett ; 9(7): 652-656, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30034595

RESUMO

Identification of ligands that selectively activate the M1 muscarinic signaling pathway has been sought for decades to treat a range of neurological and cognitive disorders. Herein, we describe the optimization efforts focused on addressing key physicochemical and safety properties, ultimately leading to the clinical candidate MK-7622, a highly selective positive allosteric modulator of the M1 muscarinic receptor that has entered Phase II studies in patients with Alzheimer's disease.

11.
Br J Radiol ; 91(1085): 20170666, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29436848

RESUMO

OBJECTIVE: To study the influence of tumour diameter and anatomy on the success and complication rates of small renal mass (SRM, ≤4 cm) core biopsy. METHODS: Retrospective analysis of SRMs that underwent ultrasound or CT-guided biopsy. Diagnostic and complication rates were compared according to tumour size (subcategorised as axial diameter ≤2 cm, >2 to- ≤3 cm, >3-≤4 cm) and anatomical disposition (exophytic/endophytic, centrality, polar location and anterior/posterior). RESULTS: 94 patients (54 male; age range 21.8-84.3 years) with 95 SRMs underwent biopsy. The first biopsy was diagnostic in 81/95 (85.3%). Seven patients underwent repeat biopsy (6/7 diagnostic), to give an overall diagnostic rate of 91.5%. The primary diagnostic rates in the ≤2, >2-≤3 , >3-≤4 cm groups were 21/25 (84%); 38/44 (86.4%) and 22/26 (84.6%) respectively and were similar (p = 1.00). Anterior and upper pole SRMs were more likely to fail initial biopsy (odds ratio 13.8, p < 0.01; and odds ratio 4.35, p = 0.04) respectively, but other anatomical factors were not relevant. Complications occurred in 14% (all conservatively managed perinephric haematomas; Clavien-Dindo Grade 1) and size or location were not relevant. CONCLUSION: Image-guided biopsy of SRMs has a high diagnostic rate irrespective of tumour size. Anterior and upper pole location had lower diagnostic rates. Biopsy should be considered for all patients with SRMs, if the result will impact on management and we list specific scenarios where an SRM biopsy may be helpful. Advances in knowledge: SRM size does not affect the likelihood of a diagnostic biopsy.


Assuntos
Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Rim/anatomia & histologia , Rim/diagnóstico por imagem , Rim/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Carga Tumoral , Adulto Jovem
12.
Cochrane Database Syst Rev ; 1: CD011188, 2017 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-28129459

RESUMO

BACKGROUND: Kawasaki disease (KD), or mucocutaneous syndrome, is the leading cause of childhood-acquired heart disease in the developed world. There is much controversy on how best to treat children with KD and in particular who may benefit from additional treatment beyond the standard intravenous immunoglobulin (IVIG) and aspirin, such as the addition of corticosteroids. OBJECTIVES: To assess the impact of corticosteroid use on the incidence of coronary artery abnormalities in KD as either first-line or second-line treatment. Corticosteroids may be given alone or in conjunction with other accepted KD treatments. Secondary objectives include the effect of steroids on mortality, the time taken for laboratory parameters to normalise, the duration of acute symptoms (such as fever), the long-term impact of steroid use and evaluating their safety in KD and their efficacy in relevant population subgroups. SEARCH METHODS: The Cochrane Vascular Information Specialist searched Cochrane Vascular's Specialised Register (25 November 2016) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 10) in the Cochrane Library (searched 25 November 2016). Trial registries were also searched for details of ongoing or unpublished studies. SELECTION CRITERIA: We selected randomised trials involving children with all severities of KD who were treated with corticosteroids, including different types of corticosteroid and different durations of treatment. DATA COLLECTION AND ANALYSIS: MJS and GMC independently selected studies, assessed evidence quality and extracted data. This process was overseen by AJW. MAIN RESULTS: Seven trials consisting of 922 participants were included in this analysis. Trials ranged from 32 to 242 participants. On pooled analysis, corticosteroids reduced the subsequent occurrence of coronary artery abnormalities (odds ratio (OR) 0.29, 95% confidence interval (CI) 0.18 to 0.46; 907 participants; 7 studies; I² = 55%) without resultant serious adverse events (no events, 737 participants) and mortality (no events, 915 participants). In addition, corticosteroids reduced the duration of fever (mean difference (MD) -1.65 days, 95% CI -3.31 to 0.00; 210 participants; 2 studies; I² = 88%), time for laboratory parameters (erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)) to normalise (MD -2.80 days, 95% CI -4.38 to -1.22; 178 participants; 1 study) and length of hospital stay (MD -1.41 days, 95% CI -2.36 to -0.46; 39 participants; 1 study). No studies detailed outcomes beyond 24 weeks. Subgroup analysis showed some potential groups that may benefit more than others; however, further randomised controlled trials are required before this can be the basis for clinical action.Evidence quality was graded according to the GRADE system. Evidence was considered high quality for the incidence of serious adverse events, mortality and time for laboratory parameters to normalise. Evidence was considered moderate for the incidence of coronary artery abnormalities due to potential inconsistencies in data geography and patient benefits according to grouping. Evidence was moderate for duration of clinical symptoms (fever, rash) due to potential subjectivity in measurement. Evidence was moderate for length of hospital stay as only one study recorded this outcome. This means that we are reasonably confident that the true effect is close to that estimated in this work. AUTHORS' CONCLUSIONS: Moderate-quality evidence shows that use of steroids in the acute phase of KD can be associated with improved coronary artery abnormalities, shorter duration of hospital stay and a decreased duration of clinical symptoms. High-quality evidence shows reduced inflammatory marker levels. There were insufficient data available regarding incidence of adverse effects attributable to steroids, mortality and long-term (> 1 year) coronary morbidity. Certain groups, including those based in Asia, those with higher risk scores, and those receiving longer steroid treatment may have greater benefit from steroid use, especially with decreasing rates of heart problems, but more tests are needed to answer these questions. Evidence presented in this study suggests that treatment with a long course of steroids should be considered for all children diagnosed with KD until further studies are performed.


Assuntos
Corticosteroides/uso terapêutico , Doença da Artéria Coronariana/prevenção & controle , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Doença Aguda , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Metilprednisolona/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Prednisolona/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
ScientificWorldJournal ; 2017: 4028352, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29387777

RESUMO

INTRODUCTION: The aim of this study was to evaluate the diagnostic utility and impact on clinical management of after-hours CT scans investigating abdominal pain in surgical patients. METHODS: After-hours CT A/P reports investigating the acute surgical abdomen were compared with clinical outcomes and histopathological findings to assess sensitivity and specificity of CT reporting. Comparisons between CT reports and clinical notes were made. CT scans were categorised as having direct effects on clinical management, ruling out a serious pathology, ruling out a nonserious pathology, or having no effect. Discrepancies between information in case-notes and information provided to radiologists were also analysed. RESULTS: 79 clinical notes were located. After-hours CT demonstrated 91% sensitivity and 82% reporting specificity using clinical outcomes as the standard. In the 26 patients with histopathological findings, CT reports demonstrated 91% sensitivity. In 79.7% of cases, CT scanning had an impact on management. In 35.4% of cases, an indication for scanning was not documented with variation in clinical information in 8.9% of cases. DISCUSSION: This study demonstrates after-hours CT A/P reports result in significant impacts on clinical management of surgical patients with acute abdominal pain. Improvements in providing information when requesting scans are however needed to facilitate accurate reporting.


Assuntos
Dor Abdominal/diagnóstico por imagem , Dor Pélvica/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
Bioorg Med Chem ; 25(2): 496-513, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914948

RESUMO

Triazolopyridine ethers with mGlu2 positive allosteric modulator (PAM) activity are disclosed. The synthesis, in vitro activity, and metabolic stability data for a series of analogs is provided. The effort resulted in the discovery of a potent, selective, and brain penetrant lead molecule BMT-133218 ((+)-7m). After oral administration at 10mg/kg, BMT-133218 demonstrated full reversal of PCP-stimulated locomotor activity and prevented MK-801-induced working memory deficits in separate mouse models. Also, reversal of impairments in executive function were observed in rat set-shifting studies at 3 and 10mg/kg (p.o.). Extensive plasma protein binding as the result of high lipophilicity likely limited activity at lower doses. Optimized triazolopyridine ethers offer utility as mGlu2 PAMs for the treatment of schizophrenia and merit further preclinical investigation.


Assuntos
Éteres/farmacologia , Piridinas/farmacologia , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Esquizofrenia/tratamento farmacológico , Triazóis/farmacologia , Administração Oral , Regulação Alostérica/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Éteres/administração & dosagem , Éteres/química , Haplorrinos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Estrutura Molecular , Piridinas/administração & dosagem , Piridinas/química , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato Metabotrópico/metabolismo , Esquizofrenia/metabolismo , Relação Estrutura-Atividade , Triazóis/administração & dosagem , Triazóis/química
15.
Cochrane Database Syst Rev ; (8): CD011205, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27482837

RESUMO

BACKGROUND: Pulmonary hypertension is a condition of complex aetiology that culminates in right heart failure and early death. Soluble guanylate cyclase (sGC) stimulators are a promising class of agents that have recently gained approval for use. OBJECTIVES: To evaluate the efficacy of sGC stimulators in pulmonary hypertension. SEARCH METHODS: We searched CENTRAL (Cochrane Central Register of Controlled Trials), MEDLINE, EMBASE and the reference lists of articles. Searches are current as of 12 February 2016. SELECTION CRITERIA: We selected randomised controlled trials (RCTs) involving participants with pulmonary hypertension of all ages, severities and durations of treatment. DATA COLLECTION AND ANALYSIS: AW, MS and RW independently selected studies, assessed evidence quality and extracted data. This process was overseen by RT and SG. All included studies were sponsored by the drug manufacturer. MAIN RESULTS: Five trials involving 962 participants are included in this review. All trials were of relatively short duration (< 16 weeks). Due to the heterogenous aetiology of pulmonary hypertension in participants, results are best considered according to each pulmonary hypertension subtype.Pooled analysis shows a mean difference (MD) increase in six-minute walking distance (6MWD) of 30.13 metres (95% CI 5.29 to 54.96; participants = 659; studies = 3). On subgroup analysis, for pulmonary arterial hypertension (PAH) there was no effect noted (6MWD; MD 11.91 metres, 95% CI -44.92 to 68.75; participants = 398; studies = 2), and in chronic thromboembolic pulmonary hypertension (CTEPH) sGC stimulators improved 6MWD by an MD of 45 metres (95% CI 23.87 to 66.13; participants = 261; studies = 1). Data for left heart disease-associated PH was not available for pooling. Importantly, when participants receiving phosphodiesterase inhibitors were excluded, sGC stimulators increased 6MWD by a MD of 36 metres in PAH. The second primary outcome, mortality, showed no change on pooled analysis against placebo (Peto odds ratio (OR) 0.57, 95% CI 0.18 to 1.80).Pooled secondary outcomes include an increase in World Health Organization (WHO) functional class (OR 1.53, 95% CI 0.87 to 2.72; participants = 858; studies = 4), no effect on clinical worsening (OR 0.45, 95% CI 0.17 to 1.14; participants = 842; studies = 3), and a reduction in mean pulmonary artery pressure (MD -2.77 mmHg, 95% CI -4.96 to -0.58; participants = 744; studies = 5). There was no significant difference in serious adverse events on pooled analysis (OR 1.12, 95% CI 0.66 to 1.90; participants = 818; studies = 5) or when analysed at PAH (MD -3.50, 95% CI -5.54 to -1.46; participants = 344; studies = 1), left heart disease associated subgroups (OR 1.56, 95% CI 0.78 to 3.13; participants = 159; studies = 2) or CTEPH subgroups (OR 1.29, 95% CI 0.65 to 2.56; participants = 261; studies = 1).It is important to consider the results for PAH in the context of a person who is not also receiving a phosphodiesterase-V inhibitor, a contra-indication to sGC stimulator use. It should also be noted that CTEPH results are applicable to inoperable or recurrent CTEPH only.Evidence was rated according to the GRADE scoring system. One outcome was considered high quality, two were moderate, and eight were of low or very low quality, meaning that for many of the outcomes the true effect could differ substantially from our estimate. There were only minor concerns regarding the risk of bias in these trials, all being RCTs largely following the original protocol. Most trials employed an intention-to-treat analysis. AUTHORS' CONCLUSIONS: sGC stimulators improve pulmonary artery pressures in people with PAH (who are treatment naive or receiving a prostanoid or endothelin antagonist) or those with recurrent or inoperable CTEPH. In these settings this can be achieved without notable complication. However, sGC stimulators should not be taken by people also receiving phosphodiestase-V inhibitors or nitrates due to the risks of hypotension, and there is currently no evidence supporting their use in pulmonary hypertension associated with left heart disease. There is no evidence supporting their use in children. These conclusions are based on data with limitations, including unavailable data from two of the trials.


Assuntos
Guanilato Ciclase , Hipertensão Pulmonar/tratamento farmacológico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Caminhada
16.
Neuropharmacology ; 102: 121-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26522433

RESUMO

Phosphodiesterase 10A (PDE10A) inhibitors increase the functionality of striatal medium spiny neurons and produce antipsychotic-like effects in rodents by blocking PDE10A mediated hydrolysis of cAMP and/or cGMP. In the current study, we characterized a radiolabeled PDE10A inhibitor, [(3)H]BMS-843496, and developed an ex vivo PDE10 binding autoradiographic assay to explore the relationship between PDE10 binding site occupancy and the observed biochemical and behavioral effects of PDE10 inhibitors in mice. [(3)H]BMS-843496 is a potent PDE10A inhibitor with a binding affinity (KD) of 0.15 nM and a functional selectivity of >100-fold over other PDE subtypes tested. Specific [(3)H]BMS-843496 binding sites were dominant in the basal ganglia, especially the striatum, with low to moderate binding in the cortical and hippocampal areas, of the mouse and monkey brain. Systemic administration of PDE10 inhibitors produced a dose- and plasma/brain concentration-dependent increase in PDE10A occupancy measured in the striatum. PDE10A occupancy was positively correlated with striatal pCREB expression levels. PDE10A occupancy was also correlated with antipsychotic-like effects measured using the conditioned avoidance response model; a minimum of ∼40% occupancy was typically required to achieve efficacy. In contrast, a clear relationship between PDE10A occupancy and catalepsy scores, a potential extrapyramidal symptom readout in rodent, was not evident.


Assuntos
Antipsicóticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Animais , Sítios de Ligação , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Macaca fascicularis , Masculino , Camundongos , Camundongos Knockout , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo
18.
ACS Med Chem Lett ; 5(5): 604-8, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24900888

RESUMO

Selective activation of the M1 muscarinic receptor via positive allosteric modulation represents an original approach to treat the cognitive decline in patients with Alzheimer's disease. A series of naphthyl-fused 5-membered lactams were identified as a new class of M1 positive allosteric modulators and were found to possess good potency and in vivo efficacy.

19.
ACS Med Chem Lett ; 3(12): 1070-4, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24900430

RESUMO

Selective activation of the M1 muscarinic receptor via positive allosteric modulation represents an approach to treat the cognitive decline in patients with Alzheimer's disease. A series of amides were examined as a replacement for the carboxylic acid moiety in a class of quinolizidinone carboxylic acid M1 muscarinic receptor positive allosteric modulators, and leading pyran 4o and cyclohexane 5c were found to possess good potency and in vivo efficacy.

20.
J Med Chem ; 54(13): 4773-80, 2011 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-21682298

RESUMO

One approach to ameliorate the cognitive decline in Alzheimer's disease (AD) has been to restore neuronal signaling from the basal forebrain cholinergic system via the activation of the M(1) muscarinic receptor. A number of nonselective M(1) muscarinic agonists have previously shown positive effects on cognitive behaviors in AD patients, but were limited due to cholinergic adverse events thought to be mediated by the activation of the M(2) to M(5) subtypes. One strategy to confer selectivity for M(1) is the identification of positive allosteric modulators, which would target an allosteric site on the M(1) receptor rather than the highly conserved orthosteric acetylcholine binding site. Quinoline carboxylic acids have been previously identified as highly selective M(1) positive allosteric modulators with good pharmacokinetic and in vivo properties. Herein is described the optimization of a novel quinolizidinone carboxylic acid scaffold with 4-cyanopiperidines being a key discovery in terms of enhanced activity. In particular, modulator 4i gave high plasma free fractions, enhanced central nervous system (CNS) exposure, was efficacious in a rodent in vivo model of cognition, and afforded good physicochemical properties suitable for further preclinical evaluation.


Assuntos
Colinérgicos/síntese química , Nitrilas/síntese química , Nootrópicos/síntese química , Piperidinas/síntese química , Quinolizidinas/síntese química , Quinolizinas/síntese química , Receptor Muscarínico M1/fisiologia , Regulação Alostérica , Animais , Disponibilidade Biológica , Células CHO , Colinérgicos/química , Colinérgicos/farmacologia , Cricetinae , Cricetulus , Medo/efeitos dos fármacos , Humanos , Masculino , Camundongos , Nitrilas/química , Nitrilas/farmacologia , Nootrópicos/química , Nootrópicos/farmacologia , Piperidinas/química , Piperidinas/farmacologia , Quinolizidinas/química , Quinolizidinas/farmacologia , Quinolizinas/química , Quinolizinas/farmacologia , Relação Estrutura-Atividade
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