RESUMO
Quinuclidine-containing spirooxazolines, as described in the previous report in this series, were demonstrated to have utility as α7 nicotinic acetylcholine receptor (α7 nAChR) partial agonists. In this work, the SAR of this chemotype was expanded to include an array of diazine heterocyclic substitutions. Many of the heterocyclic analogs were potent partial agonists of the α7 receptor, selective against other nicotinic receptors and the serotinergic 5HT3A receptor. (1'S,3'R,4'S)-N-(6-phenylpyrimidin-4-yl)-4H-1'-azaspiro[oxazole-5,3'-bicyclo[2.2.2]octan]-2-amine, a potent and selective α7 nAChR partial agonist, was demonstrated to improve cognition in the mouse novel object recognition (NOR) model of episodic memory.
Assuntos
Desenho de Fármacos , Octanos/síntese química , Pirimidinas/síntese química , Compostos de Espiro/síntese química , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Cognição/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Modelos Animais de Doenças , Camundongos , Estrutura Molecular , Octanos/química , Octanos/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Relação Estrutura-AtividadeRESUMO
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.
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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/químicaRESUMO
PURPOSE: To evaluate the effect of an exercise therapy concept (the Tübingen exercise therapy approach THüKo) for increasing hip muscle strength (HMS) in patients with hip osteoarthritis (OA), and to investigate whether patients do adhere to the intervention and if there are any adverse events related to the intervention. METHODS: A total of 210 hip OA patients (89 females, 121 males) were randomized into a 12-week exercise intervention (THüKo) including group sessions (1/week) and home exercising (2/week), a placebo ultrasound group (1/week) or a control group (no treatment). HMS was measured as isometric peak torque of hip abduction, adduction, flexion, and extension. Adherence to exercise and safety aspects were monitored as additional outcomes. RESULTS: Baseline adjusted post intervention HMS of the THüKo group were higher compared to the control group (differences of 0.11-0.27 Nm/kg, p < 0.01) and to the placebo ultrasound group (differences of 0.09-0.19 Nm/kg, p < 0.01). Adherence to exercise was high (about 90%). No subject had to refuse from training because of an exercise related adverse event and exercise related pain was only of intermittent nature without sustainable adverse effects. CONCLUSIONS: The Tübingen exercise therapy approach has shown to have a significant positive effect on HMS. Its implementation has shown to be feasible and safe according to the percentage of exercise participation and the absence of sustainable adverse events.
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Terapia por Exercício/métodos , Força Muscular , Osteoartrite do Quadril/terapia , Adulto , Idoso , Terapia por Exercício/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Segurança do Paciente , Amplitude de Movimento ArticularRESUMO
Schizophrenia is a serious illness that affects millions of patients and has been associated with N-methyl-d-aspartate receptor (NMDAR) hypofunction. It has been demonstrated that activation of metabotropic glutamate receptor 5 (mGluR5) enhances NMDA receptor function, suggesting the potential utility of mGluR5 positive allosteric modulators (PAMs) in the treatment of schizophrenia. Herein we describe the optimization of an mGluR5 PAM by replacement of a phenyl with aliphatic heterocycles and carbocycles as a strategy to reduce bioactivation in a biaryl acetylene chemotype. Replacement with a difluorocyclobutane followed by further optimization culminated in the identification of compound 32, a low fold shift PAM with reduced bioactivation potential. Compound 32 demonstrated favorable brain uptake and robust efficacy in mouse novel object recognition (NOR) at low doses.
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Oxazolidinonas/farmacologia , Piridinas/farmacologia , Receptor de Glutamato Metabotrópico 5/metabolismo , Regulação Alostérica/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Humanos , Camundongos , Estrutura Molecular , Oxazolidinonas/síntese química , Oxazolidinonas/química , Piridinas/síntese química , Piridinas/química , Ratos , Relação Estrutura-AtividadeRESUMO
Herein we describe the structure activity relationships uncovered in the pursuit of an mGluR5 positive allosteric modulator (PAM) for the treatment of schizophrenia. It was discovered that certain modifications of an oxazolidinone-based chemotype afforded predictable changes in the pharmacological profile to give analogs with a wide range of functional activities. The discovery of potent silent allosteric modulators (SAMs) allowed interrogation of the mechanism-based liabilities associated with mGluR5 activation and drove our medicinal chemistry effort toward the discovery of low efficacy (fold shift) PAMs devoid of agonist activity. This work resulted in the identification of dipyridyl 22 (BMS-952048), a compound with a favorable free fraction, efficacy in a rodent-based cognition model, and low potential for convulsions in mouse.
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Convulsivantes/química , Oxazolidinonas/química , Receptor de Glutamato Metabotrópico 5/metabolismo , Regulação Alostérica/efeitos dos fármacos , Animais , Convulsivantes/metabolismo , Convulsivantes/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Oxazolidinonas/metabolismo , Oxazolidinonas/farmacologia , Ratos , Receptor de Glutamato Metabotrópico 5/agonistas , Receptor de Glutamato Metabotrópico 5/química , Reconhecimento Psicológico/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Widespread uptake of the coronavirus disease 2019 (COVID-19) vaccinations has become the world's championed defense against the global pandemic. Four vaccines have been either approved or authorized for emergency use by the FDA, and at this time, over 13 billion doses of these vaccines have been administered around the world. Unfortunately, uncommon and sometimes unforeseen side effects such as small-vessel vasculitis have been reported. In this case report, we present a 74-year-old woman with a history of hypertension, type 2 diabetes mellitus, and hypothyroidism who developed microscopic polyangiitis (MPA) following the second dose of the Pfizer-BioNTech mRNA vaccine for COVID-19. The diagnosis of MPA was confirmed by a kidney biopsy. The autoimmune condition progressed to pericardial effusion and eventual cardiac tamponade, which is occasionally seen in the disease. In this patient's case, we suspect there to be a temporal association between mRNA COVID-19 vaccination and the development of MPA. Direct causation has not been determined.
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Surgical castration of piglets is generally recognized as a painful procedure, but there is currently no gold standard for the assessment of pain behavior in piglets. However, pain assessment is essential for evaluating the effectiveness of local anesthetics. In this study, we investigated the efficacy of four local anesthetics in terms of pain relief during and after surgical castration in three sequential study parts. To do so, we filmed 178 piglets before the applied procedures, after injection of the local anesthetic, and up to 24 h after castration (five observation times in total) in an observation arena and compared their behavior before and after castration and between treatments and control groups. The results showed significant differences in the behavior of the piglets before and after castration and between the sham-castrated control group and the control group castrated without anesthesia. The different local anesthesia treatment groups showed diverging differences to the control groups. The most frequently shown pain-associated behaviors of the piglets were changes in tail position and hunched back posture. We observed a reduction but no complete elimination of the expressed pain-associated behaviors after local anesthesia. Several behavioral changes-such as changes in tail position, hunched back posture or tail wagging-persisted until the day after castration. Owing to the limited duration of the effects of the local anesthetics, local anesthesia did not influence long-term pain.
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HIV infection is characterized by sustained immune activation, which is reflected by activated T cells and, in particular, by increased levels of phosphorylated STAT proteins. Here, we hypothesized that T-cell activation in HIV infection is partially due to the inability of SOCS-1 and SOCS-3 to control the JAK/STAT pathway. We found higher levels of SOCS-1/3 mRNA levels in CD4(+) T cells of HIV-infected patients than in healthy controls. However, SOCS protein levels were lower, explaining the lack of attenuation of the JAK/STAT pathway. Infection of CD4(+) T cells alone did not activate STATs, while ex vivo infection of PBMC did, indicating that non-T cells critical for shaping the immune response, e.g. DC were responsible for the STAT-1 activation. Supernatants from ex vivo-infected PBMC transferred to CD4(+) T cells induced JAK/STAT activation, pointing to a central role of soluble factors. Notably, over-expression of SOCS-1/3 in CD4(+) T cells prevented JAK/STAT activation. Thus, HIV infection interferes with SOCS-1/3 expression driving immune activation. Sustained immune activation disrupts the lymphoid system and favors HIV replication since HIV preferentially infects activated cells. We speculate that regulating SOCS may be a potential way to counteract immune activation in HIV disease.
Assuntos
Infecções por HIV/imunologia , Proteínas Supressoras da Sinalização de Citocina/imunologia , Adulto , Células Cultivadas , Regulação da Expressão Gênica , Infecções por HIV/metabolismo , Humanos , Janus Quinases/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Linfócitos T/imunologiaRESUMO
The present study evaluated the effects of two injection techniques in combination with lidocaine or mepivacaine for piglets undergoing castration. To improve ease of use, a cannula with side holes (one-step fenestrated (F)) was invented to simultaneously deliver a local anesthetic into the testis and scrotum and was compared to a two-step injection technique. The distribution of a lidocaine/contrast agent mixture using the two methods was examined using computed tomography. Piglets were randomly divided into treatment groups: handling, castration without pain relief and castration after lidocaine or mepivacaine injection using the one-step F or two-step method. Acute physiological responses to noxious stimuli were evaluated by measuring the mean arterial blood pressure (MAP), heart rate (HR) and nocifensive movements. Fos protein expression in the spinal dorsal cord was semi-quantitatively analyzed. Both injection techniques achieved similar distribution patterns. The one-step F method was faster and easier. Injection was not associated with significant changes in MAP or HR, but Mepi1 and NaCl elicited significantly increased nocifensive movements. Both techniques significantly reduced MAP and nocifensive movements when the spermatic cords were cut, regardless of the local anesthetic type. Compared to NaCl, only the lidocaine treatments significantly reduced HR during skin incision. Lido2 significantly reduced Fos protein expression.
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The objective of this study was to investigate the electroencephalographic reaction pattern and FOS protein expression in male piglets undergoing surgical castration under light isoflurane anaesthesia with or without local anaesthesia. The experiment was conducted under isoflurane anaesthesia to exclude the effect of the affective components of pain on the measurements. Changes in the oscillatory activity of the cerebral cortex over a 90 s period after noxious stimulation or simulated interventions were analysed. FOS expression was determined postmortem by performing immunohistochemistry in the dorsal horn of the spinal cord. The analysis of the response to an interdigital pinch revealed a biphasic reaction pattern in the electroencephalogram (EEG) that similarly was observed for the surgical stimuli during the castration procedure in the group without analgesia. This EEG response was attenuated or altered by the application of local anaesthetics. Immunohistochemical staining for FOS indicated a lower expression in the handling and in three local anaesthetic groups than in the animals castrated without pain relief. The findings indicate that EEG and FOS expression may serve as indicators for nociception in piglets under light isoflurane anaesthesia. A lower activation of nociceptive pathways occurs during castration after the application of local anaesthetics. However, EEG and FOS analyses should be combined with additional parameters to assess nociception, e.g., haemodynamic monitoring.
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Chronic immune activation is a major cause for progressive immunodeficiency in human immunodeficiency virus type-1 (HIV) infection. The underlying trigger, however, remains largely unknown. HIV single-stranded RNA is a potent immune activator by triggering Toll-like receptor (TLR) 7/8. Thus, we hypothesized that sustained TLR7 triggering induces chronic immune activation and thereby contributes to progressive immunodeficiency. We used the synthetic compound R848 or a mixture of uridine-rich HIV single-stranded (ss) RNA oligonucleotides--both are potent TLR7/8 agonists--to explore the effects of sustained TLR7 triggering on the murine lymphoid system. Sustained TLR7 triggering induced an immunopathology reminiscent of progressive lymphoid destruction in HIV disease; we observed lymphopenia, elevated proinflammatory cytokines, splenomegaly, contracted lymphoid subsets, and lymphoid microarchitecture alteration with reduced marginal zone B-lymphocytes. Upon exposure to inactivated vesiculo-stomatitis virus, antibody production was abolished, although splenic lymphocytes were activated and total IgG was elevated. Our data imply that HIV itself may directly contribute to immune activation and dysfunction by stimulating TLR7. Thus, manipulation of TLR7 signaling may be a potential strategy to reduce chronic hyper-immune activation and, thereby, disease progression in HIV infection.
Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Linfócitos B/imunologia , HIV-1 , Imidazóis/farmacologia , Glicoproteínas de Membrana/agonistas , Glicoproteínas de Membrana/imunologia , RNA Viral/imunologia , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/imunologia , Síndrome da Imunodeficiência Adquirida/genética , Síndrome da Imunodeficiência Adquirida/patologia , Animais , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Linfócitos B/patologia , Feminino , Humanos , Imidazóis/imunologia , Imunoglobulina G/imunologia , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , RNA Viral/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptor 7 Toll-Like/genética , Receptor 8 Toll-Like/agonistas , Receptor 8 Toll-Like/genética , Receptor 8 Toll-Like/imunologiaRESUMO
BACKGROUND: Hip osteoarthritis (hip OA) is a disease with a major impact on both national economy and the patients themselves. Patients suffer from pain and functional impairment in activities of daily life which are associated with a decrease in quality of life. Conservative therapeutic interventions such as physical exercises aim at reducing pain and increasing function and health-related quality of life. However, there is only silver level evidence for efficacy of land-based physical exercise in the treatment of hip OA. The purpose of this randomized controlled trial is to determine whether the specific 12-week exercise regime "Hip School" can decrease bodily pain and improve physical function and life quality in subjects with hip osteoarthritis. METHODS/DESIGN: 217 participants with hip OA, confirmed using the clinical score of the American College of Rheumatology, are recruited from the community and randomly allocated to one of the following groups: (1) exercise regime "Hip School", n = 70; (2) Non-intervention control group, n = 70; (3) "Sham" ultrasound group, n = 70; (4) Ultrasound group, n = 7. The exercise regime combines group exercises (1/week, 60-90') and home-based exercises (2/week, 30-40'). Sham ultrasound and ultrasound are given once a week, 15'. Measures are taken directly prior to (M1) and after (M2) the 12-week intervention period. Two follow-ups are conducted by phone 16 and 40 weeks after the intervention period. The primary outcome measure is the change in the subscale bodily pain of the SF36 from M1 to M2. Secondary outcomes comprise the WOMAC score, SF36, isometric strength of hip muscles, spatial-temporal and discrete measures derived from clinical gait analysis, and the length of the centre of force path in different standing tasks. An intension-to-treat analysis will be performed using multivariate statistics (group × time). DISCUSSION: Results from this trial will contribute to the evidence regarding the effect of a hip-specific exercise regime on physical function, pain, and health-related quality of life in patients with hip osteoarthritis. TRIAL REGISTRATION: German Clinical Trial Register DRKS00000651.
Assuntos
Terapia por Exercício/educação , Terapia por Exercício/métodos , Osteoartrite do Quadril/reabilitação , Osteoartrite do Quadril/terapia , Projetos de Pesquisa/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artralgia/fisiopatologia , Artralgia/reabilitação , Artralgia/terapia , Medicina Baseada em Evidências/métodos , Feminino , Alemanha , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiologia , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Osteoartrite do Quadril/fisiopatologia , Qualidade de Vida , Terapia por Ultrassom/métodos , Ultrassonografia , Adulto JovemRESUMO
Surgical castration of male piglets without analgesia is a painful procedure. This prospective, randomized and double-blinded study aimed to evaluate the analgesic effects of four different local anesthetics for piglet castration during the first week of life. In total, 54 piglets aged 3 to 7 days were distributed into 6 treatment groups: handling (H); castration without pain relief (sodium chloride, NaCl); and castration with a local anesthetic: 4% procaine (P), 2% lidocaine (L), 0.5% bupivacaine (B) or 20 mg/ml mepivacaine (M). By excluding stress and fear as disruptive factors via a minimum anesthesia model, all piglets received individual minimum alveolar concentration (MAC) isoflurane anesthesia. Twenty minutes before castration, all treatment groups except group H received one injection per testis. Then, 0.5 ml of a local anesthetic or NaCl was injected intratesticularly (i.t.), and 0.5 ml was administered subscrotally. Acute physiological responses to noxious stimuli at injection and castration were evaluated by measuring blood pressure (BP), heart rate (HR), cortisol, epinephrine, norepinephrine and chromogranin A (CgA); limb movements were quantified. The results confirm that castration without analgesia is highly painful. Surgical castration without pain relief revealed significant changes in mean arterial blood pressure (MAP) and HR. Local anesthetic administration significantly reduced changes in BP and HR associated with castration. Piglets receiving a preoperative local anesthetic exhibited the fewest limb movements during castration, while the NaCl group exhibited the most. Injection itself was not associated with significant changes in MAP or HR. However, many piglets exhibited limb movements during injection, indicating that the injection itself causes nociceptive pain. No significant differences were found between groups regarding parameters of plasma cortisol, catecholamines and CgA. In conclusion, all four local anesthetics administered are highly effective at reducing signs of nociception during castration under light isoflurane anesthesia. However, injection of a local anesthetic seems to be painful.
Assuntos
Anestesia Geral/veterinária , Anestésicos Locais/administração & dosagem , Pressão Sanguínea , Castração/veterinária , Extremidades/fisiologia , Movimento , Animais , Animais Recém-Nascidos , Castração/métodos , Catecolaminas/sangue , Frequência Cardíaca , Hidrocortisona/sangue , Masculino , SuínosRESUMO
The aim of the present study was to investigate the effect of four local anesthetics on pain relief during surgical castration under standardized conditions in conscious piglets. Therefore, 71 male piglets (three to seven days) were distributed into control groups (handling, castration without anesthesia or analgesia) and local anesthetic trial groups (procaine, lidocaine, bupivacaine, mepivacaine). Then, 20 min prior to castration, animals of the treatment groups, except piglets in the handling group, received an injection of a local anesthetic or sodium chloride of 0.5 mL intratesticularly and 0.5 mL subscrotally. During injection and castration, defensive behavior was evaluated. Locomotor activity, as well as postoperative bleeding, wound healing and average daily weight gain were assessed to detect side effects. The injection caused increased defensive movements, significantly in the bupivacaine group. Lidocaine and mepivacaine significantly reduced defensive movements during castration, and procaine and bupivacaine only during severing of the spermatic cord. Impairments of locomotor activity were found in piglets injected with lidocaine, bupivacaine or sodium chloride. Considering healing, bleeding and weight gain, no negative impacts were observed. In conclusion, lidocaine and mepivacaine were able to achieve significant pain relief during the castration procedure, whereas procaine and bupivacaine only during the severing of the spermatic cord. Moreover, the injection of bupivacaine seemed to be painful itself.
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OBJECTIVES: This study is aimed to evaluate the management of acute kidney injury (AKI) in our inner city, American hospital. We intended to ascertain whether or not there is prompt recognition of AKI in cirrhosis according to International Club of Ascites and acute kidney injury network criteria as well how effective we are at distinguishing among different causes of AKI. We aimed to calculated the mortality of hepatorenal syndrome (HRS) in our hospital, and to evaluate the adequacy of the established treatment of AKI at each stage of its algorithm. PATIENTS AND METHODS: ICD diagnostic codes were used to identify patients with liver cirrhosis and acute renal failure. A total of 725 patients met the search criteria. We excluded the patients without clinical or imaging evidence of ascites, heart failure, on hemodialysis, baseline creatinine more than 1.5 mg/dl and patients who died within 48 h of developing acute renal failure. 291 patients met the inclusion criteria. All statistical analyses were performed using SPSS version 23.0 software with a two-sided significance level set at P value less than 0.05. RESULTS: Mean age was 55.7 ± 0.61 and baseline serum creatinine was 0.94 ± 0.14. 66.5% of patients were African American, 27.3%, Hispanic, and 4.3% White. The average rise in creatinine from baseline was 1.36 ± 0.08 mg/dl. 27.2% of patients met the diagnostic criteria of HRS. 92.3% of patients with HRS received intravenous fluids and 75.4% received intravenous albumin within 48 h of acute creatinine rise. The in-hospital mortality rate was 14.1, 23.3, and 41.5% for patients with pre-renal azotemia, ARF, and HRS, respectively (P < 0.01). CONCLUSION: This study demonstrates that with present tools, there is significantly higher mortality in HRS despite guideline-based treatment. Biomarkers for early diagnosis of HRS are necessary to avoid delays in initiation of HRS treatment while establishing the diagnosis. As well, worldwide standardization of the treatment of HRS will be important if the outcome is to be improved.
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Centros Médicos Acadêmicos , Albuminas/administração & dosagem , Gerenciamento Clínico , Hidratação/métodos , Síndrome Hepatorrenal/diagnóstico , Hospitais Urbanos , Biomarcadores/sangue , Creatinina/sangue , Feminino , Síndrome Hepatorrenal/epidemiologia , Síndrome Hepatorrenal/terapia , Mortalidade Hospitalar/tendências , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologiaRESUMO
Initial work in Drosophila and mice demonstrated that the transcription factor cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) is a master control gene for memory formation. The relationship between CREB and memory has also been found to be true in other species, including aplysia and rats. It is thus well-established that CREB activation plays a central role in memory enhancement and that CREB is activated during memory formation. On the basis of these findings, a phenotypic high-throughput screening campaign utilizing a CRE-luciferase (CRE-Luci) SK-N-MC cell line was performed to identify compounds that enhance transcriptional activation of the CRE promoter with a suboptimal dose of forskolin. A number of small-molecule hits of unknown mechanisms of action were identified in the screening campaign, including HT-0411. Follow-up studies suggested that the CREB activation by HT-0411 is attributed to its specific and selective inhibition of monoamine oxidase B (MAO-B). Further, HT-0411 was shown to improve 24 h memory in rodents in a contextual fear conditioning model. This report describes the lead optimization of a series of 5-(1-methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl) thiophene-2-carboxamides that were identified as novel, potent, and selective inhibitors of MAO-B. Extensive SAR studies and in vivo behavioral evaluations of this and other related analogue series identified a number of potential clinical development candidates; ultimately, compound 8f was identified as a candidate molecule with high selectivity toward MAO-B (29-56 nM) over MAO-A (19% inhibition at a screening concentration of 50 µM), an excellent profile against a panel of other enzymes and receptors, good pharmacokinetic properties in rodents and dogs, and efficacy in multiple rodent memory models.
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Ácidos Carboxílicos/administração & dosagem , Ácidos Carboxílicos/química , Cognição/efeitos dos fármacos , Memória/efeitos dos fármacos , Monoaminoxidase/metabolismo , Nootrópicos/administração & dosagem , Nootrópicos/química , Amidas/administração & dosagem , Amidas/química , Animais , Cognição/fisiologia , Relação Dose-Resposta a Droga , Masculino , Memória/fisiologia , Camundongos Endogâmicos C57BL , Inibidores da Monoaminoxidase/administração & dosagem , Inibidores da Monoaminoxidase/química , Ratos , Resultado do TratamentoRESUMO
The α7 nicotinic acetylcholine receptor is thought to play an important role in human cognition. Here we describe the in vivo effects of BMS-902483, a selective potent α7 nicotinic acetylcholine receptor partial agonist, in relationship to α7 nicotinic acetylcholine receptor occupancy. BMS-902483 has low nanomolar affinity for rat and human α7 nicotinic acetylcholine receptors and elicits currents in cells expressing human or rat α7 nicotinic acetylcholine receptors that are about 60% of the maximal acetylcholine response. BMS-902483 improved 24h novel object recognition memory in mice with a minimal effective dose (MED) of 0.1mg/kg and reversed MK-801-induced deficits in a rat attentional set-shifting model of executive function with an MED of 3mg/kg. Enhancement of novel object recognition was blocked by the silent α7 nicotinic acetylcholine receptor agonist, NS6740, demonstrating that activity of BMS-902483 was mediated by α7 nicotinic acetylcholine receptors. BMS-902483 also reversed ketamine-induced deficits in auditory gating in rats, and enhanced ex vivo hippocampal long-term potentiation examined 24h after dosing in mice. Results from an ex vivo brain homogenate binding assay showed that α7 receptor occupancy ranged from 64% (novel object recognition) to ~90% (set shift and gating) at the MED for behavioral and sensory processing effects of BMS-902483.
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Cognição/efeitos dos fármacos , Agonismo Parcial de Drogas , Agonistas Nicotínicos/farmacologia , Quinuclidinas/farmacologia , Filtro Sensorial/efeitos dos fármacos , Compostos de Espiro/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Atenção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HEK293 , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Humanos , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Camundongos , RatosRESUMO
The therapeutic treatment of negative symptoms and cognitive dysfunction associated with schizophrenia is a significant unmet medical need. Preclinical literature indicates that α7 neuronal nicotinic acetylcholine (nACh) receptor agonists may provide an effective approach to treating cognitive dysfunction in schizophrenia. We report herein the discovery and evaluation of 1c (BMS-933043), a novel and potent α7 nACh receptor partial agonist with high selectivity against other nicotinic acetylcholine receptor subtypes (>100-fold) and the 5-HT3A receptor (>300-fold). In vivo activity was demonstrated in a preclinical model of cognitive impairment, mouse novel object recognition. BMS-933043 has completed Phase I clinical trials.
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We describe the synthesis of quinuclidine-containing spiroimidates and their utility as α7 nicotinic acetylcholine receptor (nAChR) partial agonists. A convergent synthetic route allowed for rapid SAR investigation and provided a diverse set of fused 6,5-heteroaryl analogs. Two potent and selective α7 nAChR partial agonists, (1'S,3'R,4'S)-N-(7-bromopyrrolo[2,1-f][1,2,4]triazin-4-yl)-4H-1'-azaspiro[oxazole-5,3'-bicyclo[2.2.2]octan]-2-amine (20) and (1'S,3'R,4'S)-N-(7-chloropyrrolo[2,1-f][1,2,4]triazin-4-yl)-4H-1'-azaspiro[oxazole-5,3'-bicyclo[2.2.2]octan]-2-amine (21), were identified. Both agonists improved cognition in a preclinical rodent model of learning and memory. Additionally, 5-HT3A receptor SAR suggested the presence of a steric site that when engaged led to significant loss of affinity at that receptor.
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It is essential to identify improved capabilities to accurately identify, confirm, and/or quantify radiological exposure and injury in order to inform critical triage, diagnosis, and treatment decisions. Herein the authors report characteristic requirements and potential Concepts of Operations (CONOPS) for biodosimetry tools employed in operational environments. While similar significant efforts have been completed in this area for the U.S. civilian sector, limited perspectives are published in the peer-reviewed literature regarding the use of radiological diagnostic technologies in deployed military medical treatment settings. Two radiological exposure scenarios were developed to clarify the diagnostic performance criteria and identify capability gaps. The emerging technology areas associated with radiation exposure diagnostics were reviewed and assessed to gauge their suitability in supporting triage, treatment, and return to duty decisions within the military medical support system.