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1.
J Geriatr Psychiatry Neurol ; 37(4): 255-262, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38156442

RESUMO

BACKGROUND: Expedient diagnosis of incipient dementia is often hindered by time constraints in primary care visits, shortage of dementia specialists, and extended waitlists for comprehensive neuropsychological evaluations. METHODS: We developed the Rapid Access Memory Program (RAMP) to improve access of neuropsychological services for older adults presenting to our institutional primary care clinics with concerns of cognitive decline. RAMP provides abbreviated neurocognitive assessment, same-day patient feedback, expedited reporting to referring providers, and is financially self-supported. Here, we describe development of RAMP and clinical outcomes from the first 3 years. RESULTS: Of 160 patients seen, dementia was diagnosed in 30% and Mild Cognitive Impairment in 50%; Alzheimer's disease was the most common suspected etiology. New psychiatric diagnosis was made in about one-third (n = 54). Most frequent recommendations involved medication adjustments (initiating cholinesterase inhibitors, deprescribing anticholinergics), safety (driving, decision-making), and specialist referrals. Additionally, 27 (17%) subsequently enrolled in local research. CONCLUSIONS: Results support feasibility and utility of RAMP for connecting older adults in primary care with neuropsychological services.


Assuntos
Disfunção Cognitiva , Demência , Atenção Primária à Saúde , Humanos , Feminino , Idoso , Masculino , Demência/terapia , Idoso de 80 Anos ou mais , Disfunção Cognitiva/terapia , Testes Neuropsicológicos , Acessibilidade aos Serviços de Saúde , Doença de Alzheimer/terapia , Encaminhamento e Consulta , Pessoa de Meia-Idade
2.
Surg Endosc ; 38(3): 1163-1169, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082009

RESUMO

BACKGROUND: Although gastroesophageal reflux disease (GERD) affects 0.6% to 10% of patients operated on for one-anastomosis gastric bypass (OAGB), only about 1% require surgery to convert to Roux-en-Y gastric bypass (RYGB) [3-5]. The aim of the present study was to analyze the characteristics of OAGB patients converted to RYGB for GERD not responding to medical treatment. METHODS: This retrospective multicenter study included patients who underwent conversion from OAGB to RYGB for severe GERD. The conversion was performed with resection of the previous gastro-jejunal anastomosis and the use of the afferent loop as a new biliary loop. RESULTS: A total of 126 patients were included in the study. Of these patients, 66 (52.6%) had a past medical history of bariatric restrictive surgery (gastric banding, sleeve gastrectomy). A hiatal hernia (HH) was present in 56 patients (44.7%). The association between previous restrictive surgery and HH was recorded in 33 (26.2%) patients. Three-dimensional gastric computed tomography showed an average gastric pouch volume of 242.4 ± 55.1 cm3. Conversion to RYGB was performed on average 60 ± 35.6 months after OAGB. Seven patients (5.5%) experienced an early postoperative complication (4 patients grade IIIb and 3 grade IIb), and 3 (2.4%) a late complication. Patients showed further weight loss after RYGB conversion and an average of 24.8 ± 21.7 months after surgery, with a mean % of total weight loss (%TWL) of 6.9 ± 13.6 kg. From a clinical point of view, the problem of GERD was definitively solved in more than 90% of patients. CONCLUSIONS: Situations that weaken the esogastric junction appear to be highly frequent in patients operated on for OAGB and converted to RYGB for severe reflux. Similarly, the correct creation of the gastric pouch could play an important role in reducing the risk of conversion to RYGB for GERD.


Assuntos
Derivação Gástrica , Refluxo Gastroesofágico , Hérnia Hiatal , Obesidade Mórbida , Humanos , Derivação Gástrica/métodos , Obesidade Mórbida/cirurgia , Estômago/cirurgia , Gastrectomia/métodos , Refluxo Gastroesofágico/etiologia , Refluxo Gastroesofágico/cirurgia , Hérnia Hiatal/cirurgia , Redução de Peso , Estudos Retrospectivos
3.
Chemistry ; 29(43): e202301200, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37204016

RESUMO

Organocatalytic asymmetric transformation of common aromatic heterocycles via in situ formation of highly reactive dearomatized ortho-quinodimethane diene species and subsequent [4+2] cycloaddition with suitable dienophiles has become a powerful tool to enter cyclohexane-fused heterocycles. Most of these reactions were previously applied to benzo-fused heterocycles or poorly aromatic rings. Herein, we disclose how previously intractable aromatic imidazole rings, equipped with removable methylidene malononitrile activating handle, could be involved as competent cycloaddends with ß-aryl enals in efficient eliminative [4+2] cycloadditions under mild organocatalytic conditions. This method allowed the efficient and direct preparation of scantly represented 6,7-dihydrobenzo[d]imidazoles with optimal enantio- and regioselectivities. Post-cycloaddition chemical editing provided imidazole-based ring systems with diverse oxidation state and functional groups.

4.
Brain ; 145(10): 3681-3697, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-35583160

RESUMO

Severe spinal cord injuries result in permanent paraparesis in spite of the frequent sparing of small portions of white matter. Spared fibre tracts are often incapable of maintaining and modulating the activity of lower spinal motor centres. Effects of rehabilitative training thus remain limited. Here, we activated spared descending brainstem fibres by electrical deep brain stimulation of the cuneiform nucleus of the mesencephalic locomotor region, the main control centre for locomotion in the brainstem, in adult female Lewis rats. We show that deep brain stimulation of the cuneiform nucleus enhances the weak remaining motor drive in highly paraparetic rats with severe, incomplete spinal cord injuries and enables high-intensity locomotor training. Stimulation of the cuneiform nucleus during rehabilitative aquatraining after subchronic (n = 8 stimulated versus n = 7 unstimulated versus n = 7 untrained rats) and chronic (n = 14 stimulated versus n = 9 unstimulated versus n = 9 untrained rats) spinal cord injury re-established substantial locomotion and improved long-term recovery of motor function. We additionally identified a safety window of stimulation parameters ensuring context-specific locomotor control in intact rats (n = 18) and illustrate the importance of timing of treatment initiation after spinal cord injury (n = 14). This study highlights stimulation of the cuneiform nucleus as a highly promising therapeutic strategy to enhance motor recovery after subchronic and chronic incomplete spinal cord injury with direct clinical applicability.


Assuntos
Formação Reticular Mesencefálica , Traumatismos da Medula Espinal , Feminino , Ratos , Animais , Ratos Endogâmicos Lew , Traumatismos da Medula Espinal/terapia , Locomoção/fisiologia , Tronco Encefálico , Medula Espinal , Recuperação de Função Fisiológica/fisiologia
5.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36674990

RESUMO

Growth factors and cytokines released in the lung cancer microenvironment promote an epithelial-to-mesenchymal transition (EMT) that sustains the progression of neoplastic diseases. TGFß is one of the most powerful inducers of this transition, as it induces overexpression of the fibronectin receptor, αvß6 integrin, in cancer cells which, in turn, is strongly associated with EMT. Thus, αvß6 integrin receptors may be exploited as a target for the selective delivery of anti-tumor agents. We introduce three novel synthesized conjugates, in which a selective αvß6 receptor ligand is linked to nintedanib, a potent kinase inhibitor used to treat advanced adenocarcinoma lung cancer in clinics. The αvß6 integrin ligand directs nintedanib activity to the target cells of the tumor microenvironment, avoiding the onset of negative side effects in normal cells. We found that the three conjugates inhibit the adhesion of cancer cells to fibronectin in a concentration-dependent manner and that αvß6-expressing cells internalized the conjugated compounds, thus permitting nintedanib to inhibit 2D and 3D cancer cell growth and suppress the clonogenic ability of the EMT phenotype as well as intervening in other aspects associated with the EMT transition. These results highlight αvß6 receptors as privileged access points for dual-targeting molecular conjugates engaged in an efficient and precise strategy against non-small cell lung cancer.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Fator de Crescimento Transformador beta/metabolismo , Ligantes , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Integrinas/metabolismo , Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral , Microambiente Tumoral
6.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240111

RESUMO

Though the bulk of the COVID-19 pandemic is behind, the search for effective and safe anti-SARS-CoV-2 drugs continues to be relevant. A highly pursued approach for antiviral drug development involves targeting the viral spike (S) protein of SARS-CoV-2 to prevent its attachment to the cellular receptor ACE2. Here, we exploited the core structure of polymyxin B, a naturally occurring antibiotic, to design and synthesize unprecedented peptidomimetics (PMs), intended to target contemporarily two defined, non-overlapping regions of the S receptor-binding domain (RBD). Monomers 1, 2, and 8, and heterodimers 7 and 10 bound to the S-RBD with micromolar affinity in cell-free surface plasmon resonance assays (KD ranging from 2.31 µM to 2.78 µM for dimers and 8.56 µM to 10.12 µM for monomers). Although the PMs were not able to fully protect cell cultures from infection with authentic live SARS-CoV-2, dimer 10 exerted a minimal but detectable inhibition of SARS-CoV-2 entry in U87.ACE2+ and A549.ACE2.TMPRSS2+ cells. These results validated a previous modeling study and provided the first proof-of-feasibility of using medium-sized heterodimeric PMs for targeting the S-RBD. Thus, heterodimers 7 and 10 may serve as a lead for the development of optimized compounds, which are structurally related to polymyxin, with improved S-RBD affinity and anti-SARS-CoV-2 potential.


Assuntos
COVID-19 , Peptidomiméticos , Humanos , SARS-CoV-2 , Peptidomiméticos/farmacologia , Sítios de Ligação , Enzima de Conversão de Angiotensina 2/química , Polimixinas , Pandemias , Ligação Proteica
7.
J Synchrotron Radiat ; 29(Pt 3): 711-720, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35511004

RESUMO

The X-ray reflectivity technique can provide out-of-plane electron-density profiles of surfaces, interfaces, and thin films, with atomic resolution accuracy. While current methodologies require high surface flatness, this becomes challenging for naturally curved surfaces, particularly for liquid metals, due to the very high surface tension. Here, the development of X-ray reflectivity measurements with beam sizes of a few tens of micrometres on highly curved liquid surfaces using a synchrotron diffractometer equipped with a double crystal beam deflector is presented. The proposed and developed method, which uses a standard reflectivity θ-2θ scan, is successfully applied to study in situ the bare surface of molten copper and molten copper covered by a graphene layer grown in situ by chemical vapor deposition. It was found that the roughness of the bare liquid surface of copper at 1400 K is 1.25 ± 0.10 Å, while the graphene layer is separated from the liquid surface by a distance of 1.55 ± 0.08 Šand has a roughness of 1.26 ± 0.09 Å.

8.
BJU Int ; 130(2): 166-180, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34390120

RESUMO

OBJECTIVES: To summarize the current literature on lower urinary tract electrical sensory assessment (LUTESA), with regard to current perception thresholds (CPTs) and sensory evoked potentials (SEPs), and to discuss the applied methods in terms of technical aspects, confounding factors, and potential for lower urinary tract (LUT) diagnostics. METHODS: The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Medline (PubMed), Embase and Scopus were searched on 13 October 2020. Meta-analyses were performed and methodological qualities of the included studies were defined by assessing risk of bias (RoB) as well as confounding. RESULTS: After screening 9925 articles, 80 studies (five randomized controlled trials [RCTs] and 75 non-RCTs) were included, comprising a total of 3732 patients and 692 healthy subjects (HS). Of these studies, 61 investigated CPTs exclusively and 19 reported on SEPs, with or without corresponding CPTs. The recording of LUTCPTs and SEPs was shown to represent a safe and reliable assessment of LUT afferent nerve function in HS and patients. LUTESA demonstrated significant differences in LUT sensitivity between HS and neurological patients, as well as after interventions such as pelvic surgery or drug treatments. Pooled analyses showed that several stimulation variables (e.g. stimulation frequency, location) as well as patient characteristics might affect the main outcome measures of LUTESA (CPTs, SEP latencies, peak-to-peak amplitudes, responder rate). RoB and confounding was high in most studies. CONCLUSIONS: Preliminary data show that CPT and SEP recordings are valuable tools to more objectively assess LUT afferent nerve function. LUTESA complements already established diagnostics such as urodynamics, allowing a more comprehensive patient evaluation. The high RoB and confounding rate was related to inconsistency and inaccuracy in reporting rather than the technique itself. LUTESA standardization and well-designed RCTs are crucial to implement LUTESA as a clinical assessment tool.


Assuntos
Bexiga Urinária , Urodinâmica , Voluntários Saudáveis , Humanos , Bexiga Urinária/fisiologia
9.
Chem Rev ; 120(5): 2448-2612, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32040305

RESUMO

The principle of vinylogy states that the electronic effects of a functional group in a molecule are possibly transmitted to a distal position through interposed conjugated multiple bonds. As an emblematic case, the nucleophilic character of a π-extended enolate-type chain system may be relayed from the legitimate α-site to the vinylogous γ, ε, ..., ω remote carbon sites along the chain, provided that suitable HOMO-raising strategies are adopted to transform the unsaturated pronucleophilic precursors into the reactive polyenolate species. On the other hand, when "unnatural" carbonyl ipso-sites are activated as nucleophiles (umpolung), vinylogation extends the nucleophilic character to "unnatural" ß, δ, ... remote sites. Merging the principle of vinylogy with activation modalities and concepts such as iminium ion/enamine organocatalysis, NHC-organocatalysis, cooperative organo/metal catalysis, bifunctional organocatalysis, dicyanoalkylidene activation, and organocascade reactions represents an impressive step forward for all vinylogous transformations. This review article celebrates this evolutionary progress, by collecting, comparing, and critically describing the achievements made over the nine year period 2010-2018, in the generation of vinylogous enolate-type donor substrates and their use in chemical synthesis.

10.
Proc Natl Acad Sci U S A ; 116(28): 14270-14279, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31235580

RESUMO

Stroke is a major cause of serious disability due to the brain's limited capacity to regenerate damaged tissue and neuronal circuits. After ischemic injury, a multiphasic degenerative and inflammatory response is coupled with severely restricted vascular and neuronal repair, resulting in permanent functional deficits. Although clinical evidence indicates that revascularization of the ischemic brain regions is crucial for functional recovery, no therapeutics that promote angiogenesis after cerebral stroke are currently available. Besides vascular growth factors, guidance molecules have been identified to regulate aspects of angiogenesis in the central nervous system (CNS) and may provide targets for therapeutic angiogenesis. In this study, we demonstrate that genetic deletion of the neurite outgrowth inhibitor Nogo-A or one of its corresponding receptors, S1PR2, improves vascular sprouting and repair and reduces neurological deficits after cerebral ischemia in mice. These findings were reproduced in a therapeutic approach using intrathecal anti-Nogo-A antibodies; such a therapy is currently in clinical testing for spinal cord injury. These results provide a basis for a therapeutic blockage of inhibitory guidance molecules to improve vascular and neural repair after ischemic CNS injuries.


Assuntos
Anticorpos Anti-Idiotípicos/farmacologia , Isquemia Encefálica/tratamento farmacológico , Proteínas Nogo/genética , Receptores de Esfingosina-1-Fosfato/genética , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Isquemia Encefálica/genética , Isquemia Encefálica/imunologia , Isquemia Encefálica/patologia , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/imunologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Proteínas Nogo/antagonistas & inibidores , Proteínas Nogo/imunologia , Tratos Piramidais/efeitos dos fármacos , Tratos Piramidais/patologia , Recuperação de Função Fisiológica/genética , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Receptores de Esfingosina-1-Fosfato/imunologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/patologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/imunologia , Acidente Vascular Cerebral/patologia
11.
Anal Chem ; 93(26): 9049-9055, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34159790

RESUMO

Physical forms of active pharmaceutical ingredients (APIs) play a crucial role in drug discovery since 85% of API molecules exhibit polymorphism and sometimes complicated phase behavior, often resulting in important differences in the respective biochemical and physical properties. Characterization and quantitation of the different forms are becoming more and more essential in the pharmaceutical industry: once these characteristics are known, it is easier to choose the best solid form for development, formulation, manufacturing, and storage. Time domain-nuclear magnetic resonance (TD-NMR) has recently been used to develop a quantitation protocol for solid mixtures, named qSRC, based on the linear combination of T1 saturation recovery curves (SRCs) collected on a bench-top instrument. Despite its potentials and ease of use, a limited number of application cases have been reported in the literature since its development and many aspects remain to be clarified for the technique to be adopted as a robust routinely industrial analytical tool. In the present work, the reliability of the qSRC approach has been studied by focusing on the role played by key experimental variables, including mixture composition, signal-to-noise ratio, and T1 differences. In silico simulations were carried out for a wide range of theoretical cases to predict the expected level of accuracy obtainable for a given sample-parameter acquisition set and to clearly define the range of applicability of the method. Results of the simulation are presented alongside a comparison with three real-case studies of commercially available APIs: piroxicam, naproxen sodium, and benzocaine.


Assuntos
Imageamento por Ressonância Magnética , Preparações Farmacêuticas , Simulação por Computador , Espectroscopia de Ressonância Magnética , Reprodutibilidade dos Testes
12.
Proc Natl Acad Sci U S A ; 115(41): 10493-10498, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30254156

RESUMO

Dopaminergic signaling in the striatum, particularly at dopamine 2 receptors (D2R), has been a topic of active investigation in obesity research in the past decades. However, it still remains unclear whether variations in striatal D2Rs modulate the risk for obesity and if so in which direction. Human studies have yielded contradictory findings that likely reflect a complex nonlinear relationship, possibly involving a combination of causal effects and compensatory changes. Animal work indicates that although chronic obesogenic diets reduce striatal D2R function, striatal D2R down-regulation does not lead to obesity. In this study, we evaluated the consequences of striatal D2R up-regulation on body-weight gain susceptibility and energy balance in mice. We used a mouse model of D2R overexpression (D2R-OE) in which D2Rs were selectively up-regulated in striatal medium spiny neurons. We uncover a pathological mechanism by which striatal D2R-OE leads to reduced brown adipose tissue thermogenesis, reduced energy expenditure, and accelerated obesity despite reduced eating. We also show that D2R-OE restricted to development is sufficient to promote obesity and to induce energy-balance deficits. Together, our findings indicate that striatal D2R-OE during development persistently increases the propensity for obesity by reducing energy output in mice. This suggests that early alterations in the striatal dopamine system could represent a key predisposition factor toward obesity.


Assuntos
Corpo Estriado/metabolismo , Dieta/efeitos adversos , Metabolismo Energético , Neostriado/metabolismo , Obesidade/etiologia , Receptores de Dopamina D2/fisiologia , Animais , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Obesidade/patologia , Aumento de Peso
13.
Molecules ; 26(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34641610

RESUMO

Integrin α4ß1 belongs to the leukocyte integrin family and represents a therapeutic target of relevant interest given its primary role in mediating inflammation, autoimmune pathologies and cancer-related diseases. The focus of the present work is the design, synthesis and characterization of new peptidomimetic compounds that are potentially able to recognize α4ß1 integrin and interfere with its function. To this aim, a collection of seven new cyclic peptidomimetics possessing both a 4-aminoproline (Amp) core scaffold grafted onto key α4ß1-recognizing sequences and the (2-methylphenyl)ureido-phenylacetyl (MPUPA) appendage, was designed, with the support of molecular modeling studies. The new compounds were synthesized through SPPS procedures followed by in-solution cyclization maneuvers. The biological evaluation of the new cyclic ligands in cell adhesion assays on Jurkat cells revealed promising submicromolar agonist activity in one compound, namely, the c[Amp(MPUPA)Val-Asp-Leu] cyclopeptide. Further investigations will be necessary to complete the characterization of this class of compounds.


Assuntos
Adesão Celular/efeitos dos fármacos , Integrina alfa4beta1/química , Peptidomiméticos/química , Peptidomiméticos/farmacologia , Prolina/análogos & derivados , Humanos , Integrina alfa4beta1/antagonistas & inibidores , Células Jurkat , Ligantes , Modelos Moleculares , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Prolina/química , Prolina/farmacologia , Ligação Proteica , Conformação Proteica
14.
J Neurosci ; 39(21): 4066-4076, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-30902870

RESUMO

Loss of bladder control is common after spinal cord injury (SCI) and no causal therapies are available. Here we investigated whether function-blocking antibodies against the nerve-fiber growth inhibitory protein Nogo-A applied to rats with severe SCI could prevent development of neurogenic lower urinary tract dysfunction. Bladder function of rats with SCI was repeatedly assessed by urodynamic examination in fully awake animals. Four weeks after SCI, detrusor sphincter dyssynergia had developed in all untreated or control antibody-infused animals. In contrast, 2 weeks of intrathecal anti-Nogo-A antibody treatment led to significantly reduced aberrant maximum detrusor pressure during voiding and a reduction of the abnormal EMG high-frequency activity in the external urethral sphincter. Anatomically, we found higher densities of fibers originating from the pontine micturition center in the lumbosacral gray matter in the anti-Nogo-A antibody-treated animals, as well as a reduced number of inhibitory interneurons in lamina X. These results suggest that anti-Nogo-A therapy could also have positive effects on bladder function clinically.SIGNIFICANCE STATEMENT After spinal cord injury, loss of bladder control is common. Detrusor sphincter dyssynergia is a potentially life-threatening consequence. Currently, only symptomatic treatment options are available. First causal treatment options are urgently needed in humans. In this work, we show that function-blocking antibodies against the nerve-fiber growth inhibitory protein Nogo-A applied to rats with severe spinal cord injury could prevent development of neurogenic lower urinary tract dysfunction, in particular detrusor sphincter dyssynergia. Anti-Nogo-A therapy has entered phase II clinical trial in humans and might therefore soon be the first causal treatment option for neurogenic lower urinary tract dysfunction.


Assuntos
Anticorpos/farmacologia , Proteínas Nogo/antagonistas & inibidores , Traumatismos da Medula Espinal/complicações , Bexiga Urinaria Neurogênica/etiologia , Animais , Feminino , Ratos , Ratos Endogâmicos Lew
15.
Chemistry ; 26(59): 13468-13475, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32634263

RESUMO

In recognition of the key role played by integrins in several life-threatening dysfunctions, the search for novel small-molecule probes that selectively recognize these surface receptors is still open and widely pursued. Inspired by previously established aminoproline (Amp)-RGD based cyclopeptidomimetics with attracting αV ß3 integrin affinity and selectivity, the design and straightforward synthesis of 18 new AmpRGD chemotypes bearing additional structural variants were herein implemented, to shift toward peptide-like αV ß6 integrin targeted binders. The ligand competence of the synthesized products toward αV ß6 was evaluated in competitive binding assays on isolated receptors, and αV ß6 /αV ß3 selectivity was determined for a subgroup of compounds, resulting in the identification of four very promising candidates. SAR considerations and docking simulations allowed us to appreciate the key structural features responsible for the observed activity.


Assuntos
Cadeias beta de Integrinas/química , Oligopeptídeos/química , Peptidomiméticos , Integrina alfaVbeta3/química , Ligantes , Prolina/análogos & derivados , Prolina/química
16.
Angew Chem Int Ed Engl ; 59(45): 20055-20064, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32678935

RESUMO

The discovery of chemical methods enabling the construction of carbocycle-fused uracils which embody a three-dimensional and functional-group-rich architecture is a useful tool in medicinal chemistry oriented synthesis. In this work, an unprecedented amine-catalyzed [4+2] cross-cycloaddition is documented; it involves remotely enolizable 6-methyluracil-5-carbaldehydes and ß-aryl enals, and chemoselectively produces two novel bicyclic and tricyclic fused uracil chemotypes in good yields with a maximum level of enantiocontrol. In-depth mechanistic investigations and control experiments support an intriguing homo-synergistic organocatalytic approach, where the same amine organocatalyst concomitantly engages both aldehyde partners in a stepwise eliminative [4+2] cycloaddition, whose vinylogous iminium ion intermediate product may diverge-depending upon conditions-to either bicyclic targets by hydrolysis or tricyclic products by a second homo-synergistic trienamine-mediated stepwise [4+2] cycloaddition.

17.
Eur J Neurosci ; 50(11): 3750-3771, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31420995

RESUMO

Inhibitory GABAergic interneurons create different brain activity patterns that correlate with behavioural states. In this characterizing study, we used single-cell RNA-Seq to analyse anatomically- and electrophysiologically identified hippocampal oriens-lacunosum moleculare (OLM) interneurons. OLMs express somatostatin (Sst), generate feedback inhibition and play important roles in theta oscillations and fear encoding. Although an anatomically- and biophysically homogenous population, OLMs presumably comprise of two functionally distinct types with different developmental origins, inferred from the expression pattern of serotonin type-3a (5-HT3a, or Htr3a) receptor subunit and 5-HT excitability in a set of OLMs. To broadly characterize OLM cells, we used the Sst-Cre and the BAC transgenic Htr3a-Cre mouse lines and separately analysed SstCre-OLM and Htr3aCre-OLM types. We found a surprisingly consistent expression of Npy in OLMs, which was previously not associated with the identity of this type. Our analyses furthermore revealed uniform expression of developmental origin-related genes, including transcription factors and neurexin isoforms, without providing support for the current view that OLMs may originate from multiple neurogenic zones. Together, we found that OLMs constitute a highly homogenous transcriptomic population. Finally, our results revealed surprisingly infrequent expression of Htr3a in only ~10% of OLMs and an apparently specific expression of the 5-HT3b subunit-coding gene Htr3b in Htr3aCre-OLMs, but not in SstCre-OLMs. However, additional in situ hybridization experiments suggested that the differential expression of Htr3b may represent an unexpected consequence arising from the design of the Htr3a-Cre BAC transgenic line.


Assuntos
Hipocampo/citologia , Hipocampo/metabolismo , Interneurônios/metabolismo , RNA-Seq/métodos , Animais , Feminino , Hipocampo/química , Interneurônios/química , Masculino , Camundongos , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Receptores 5-HT3 de Serotonina/biossíntese , Receptores 5-HT3 de Serotonina/genética , Transcriptoma/fisiologia
18.
Nanomedicine ; 18: 135-145, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30849548

RESUMO

We report here the preparation, physico-chemical characterization, and biological evaluation of a new liposome formulation as a tool for tumor angiogenesis inhibition. Liposomes are loaded with sunitinib, a tyrosine kinase inhibitor, and decorated with cyclo-aminoprolineRGD units (cAmpRGD), efficient and selective ligands for integrin αVß3. The RGD units play multiple roles since they target the nanovehicles at the integrin αVß3-overexpressing cells (e.g. activated endothelial cells), favor their active cell internalization, providing drug accumulation in the cytoplasm, and likely take part in the angiogenesis inhibition by interfering in the αVß3-VEGFR2 cross-talk. Both in vitro and in vivo studies show a better efficacy of this integrated antiangiogenic tool with respect to the free sunitinib and untargeted sunitinib-loaded liposomes. This system could allow a lower administration of the drug and, by increasing the vector specificity, reduce side-effects in a prolonged antiangiogenic therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Integrina alfaVbeta3/metabolismo , Oligopeptídeos/química , Prolina/análogos & derivados , Sunitinibe/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/uso terapêutico , Animais , Adesão Celular/efeitos dos fármacos , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Humanos , Recém-Nascido , Lipídeos/química , Lipossomos , Camundongos , Nanopartículas/química , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/síntese química , Fosfolipídeos/síntese química , Fosfolipídeos/química , Fosforilação/efeitos dos fármacos , Prolina/síntese química , Prolina/química , Sunitinibe/química , Sunitinibe/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Vitronectina/metabolismo
19.
Chemistry ; 24(46): 12093-12100, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-29923243

RESUMO

Effective and selective targeting of the αV ß3 integrin subtype is of high relevance in cancer research for the development of therapeutic systems with improved efficacy and of diagnostic imaging probes. We report here a new class of highly selective, αV ß3 -targeted gold nanoparticles (AuNPs), which carry cyclic 4-aminoproline-RGD semipeptides (cAmpRGD) as the targeting moiety immobilized at low surface density on the poly(ethylene glycol) (PEG)-based nanoparticle coating. We show that these nanoparticles are potent inhibitors of the integrin-mediated melanoma tumor cell adhesion to vitronectin and are selectively internalized via receptor-mediated endocytosis. Furthermore, we have developed bifunctional cAmpRGD-functionalized AuNPs by conjugation of a fluorophore (FAM or TAMRA) to a separate set of reactive groups on the PEG-based coating. These bifunctional AuNPs not only recapitulate the binding properties of cAmpRGD-AuNPs but also can be visualized via confocal laser microscopy, allowing direct observation of nanoparticle internalization. The peculiar molecular design of these nanoparticles and their precisely defined architecture at the molecular level accounts for their selective integrin binding with very low nonspecific background.

20.
Neurourol Urodyn ; 37(4): 1266-1271, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29140562

RESUMO

AIMS: Our objective was to investigate and compare bladder function in rats assessed by metabolic cage and by urodynamic measurements in fully awake animals. METHODS: Bladder function of female Lewis rats was investigated in naïve animals by metabolic cage at baseline, 14-16 days after bladder catheter and external urethral sphincter electromyography electrode implantation in fully awake animals by urodynamics, and again by metabolic cage. RESULTS: Investigating the same animals (n = 8), voided volume, average flow, and duration of voiding were similar (P > 0.05) in naïve animals measured by metabolic cage and after catheter implantation by urodynamic measurements and by metabolic cage. In naïve animals measured by metabolic cage, voided volumes were significantly different in the light (resting phase) versus the dark (active phase) part of the 24 h cycle (mean difference 0.14 mL, 21%, P = 0.004, n = 27). CONCLUSIONS: Lower urinary tract function assessed by metabolic cage or by urodynamic meaurements in fully awake rats was indistinguishable. Thus, catheter implantation did not significantly change physiological bladder function. This shows that urodynamic measurements in awake animals are an appropriate approach to study lower urinary tract function in health and disease in animal models, directly paralleling the human diagnostic procedures.


Assuntos
Bexiga Urinária/fisiologia , Micção/fisiologia , Urodinâmica/fisiologia , Animais , Eletromiografia , Feminino , Modelos Animais , Ratos , Ratos Endogâmicos Lew , Uretra/fisiologia
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