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1.
Chemistry ; 29(53): e202301442, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37606898

RESUMO

A new fluorinated manganese porphyrin, (Mn-TPP-p-CF3 ) is reported capable of providing, based on the Mn(III)/Mn(II) equilibrium, dual 1 H relaxivity and 19 F NMR response to redox changes. The physical-chemical characterization of both redox states in DMSO-d6 /H2 O evidenced that the 1 H relaxometric and 19 F NMR properties are appropriate for differential redox MRI detection. The Mn(III)-F distance (dMn-F =9.7-10 Å), as assessed by DFT calculations, is well tailored to allow for adequate paramagnetic effect of Mn(III) on 19 F T1 and T2 relaxation times. Mn-TPP-p-CF3 has a reversible Mn(II)/Mn(III) redox potential of 0.574 V vs. NHE in deoxygenated aqueous HEPES/ THF solution. The reduction of Mn(III)-TPP-p-CF3 in the presence of ascorbic acid is slowly, but fully reversed in the presence of air oxygen, as monitored by UV-Vis spectrometry and 19 F NMR. The broad 1 H and 19 F NMR signals of Mn(III)-TPP-p-CF3 disappear in the presence of 1 equivalent ascorbate replaced by a shifted and broadened 19 F NMR signal from Mn(II)-TPP-p-CF3 . Phantom 19 F MR images in DMSO show a MRI signal intensity decrease upon reduction of Mn(III)-TPP-p-CF3 , retrieved upon complete reoxidation in air within ~24 h. 1 H NMRD curves of the Mn(III)/(II)-TPP-p-CF3 chelates in mixed DMSO/water solvent have the typical shape of Mn(II)/Mn(III) porphyrins.

2.
Photochem Photobiol Sci ; 22(11): 2607-2620, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37755667

RESUMO

The COVID-19 pandemic exposes our vulnerability to viruses that acquire the ability to infect our cells. Classical disinfection methods are limited by toxicity. Existing medicines performed poorly against SARS-CoV-2 because of their specificity to targets in different organisms. We address the challenge of mitigating known and prospective viral infections with a new photosensitizer for antimicrobial photodynamic therapy (aPDT). Photodynamic inactivation is based on local oxidative stress, which is particularly damaging to enveloped viruses. We synthesized a cationic imidazolyl chlorin that reduced by > 99.999% of the percentage inhibition of amplification of SARS-CoV-2 collected from patients at 0.2 µM concentration and 4 J cm-2. Similar results were obtained in the prevention of infection of human ACE2-expressing HEK293T cells by a pseudotyped lentiviral vector exhibiting the S protein of SARS-CoV-2 at its surface. No toxicity to human epidermal keratinocytes (HaCaT) cells was found under similar conditions. aPDT with this chlorin offers fast and safe broad-spectrum photodisinfection and can be repeated with low risk of resistance.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/química , Desinfecção , Pandemias , Células HEK293 , Estudos Prospectivos , Fotoquimioterapia/métodos , SARS-CoV-2 , Antivirais/farmacologia
3.
Acta Neuropsychiatr ; 35(2): 104-117, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36380512

RESUMO

The top-down Diagnostic and Statistical Manual/International Statistical Classification of Diseases categories of mood disorders are inaccurate, and their dogmatic nature precludes both deductive (as indisputable) and inductive (as top-down) remodelling of case definitions. In trials, psychiatric rating scale scores employed as outcome variables are invalid and rely on folk psychology-like narratives. Using machine learning techniques, we developed a new precision nomothetic model of mood disorders with a recurrence of illness (ROI) index, a new endophenotype class, namely Major Dysmood Disorder (MDMD), characterised by increased ROI, a more severe phenome, and more disabilities. Nonetheless, our previous studies did not compute Research and Diagnostic Algorithmic Rules (RADAR) to diagnose MDMD and score ROI, lifetime (LT), and current suicidal behaviours, as well as the phenome of mood disorders. Here, we provide rules to compute bottom-up RADAR scores for MDMD, ROI, LT and current suicidal ideation and attempts, the phenome of mood disorders, and the lifetime trajectory of mood disorder patients from a family history of mood disorders and substance abuse to adverse childhood experiences, ROI, and the phenome. We also demonstrate how to plot the 12 major scores in a single RADAR graph, which displays all features in a two-dimensional plot. These graphs allow the characteristics of a patient to be displayed as an idiomatic fingerprint, allowing one to estimate the key traits and severity of the illness at a glance. Consequently, biomarker research into mood disorders should use our RADAR scores to examine pan-omics data, which should be used to enlarge our precision models and RADAR graph.


Assuntos
Transtornos do Humor , Transtornos Relacionados ao Uso de Substâncias , Humanos , Transtornos do Humor/diagnóstico , Transtornos do Humor/psicologia , Ideação Suicida , Tentativa de Suicídio/psicologia , Fatores de Risco
4.
Psychiatr Q ; 93(3): 813-840, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35739407

RESUMO

Severe mental illness could be defined through its diagnosis, disability, and duration, and one of their main characteristics is the high prevalence of some clinical conditions such as obesity and metabolic syndrome. Although the promotion of a healthier lifestyle has been demonstrated as an effective strategy to reduce both body mass index and abdominal circumference in this population, there is a lack of studies focusing on digital intervention in this population. The aim of this systematic review was to evaluate the efficacy of studies that used digital technologies to reduce weight, body mass index (BMI) and abdominal circumference in individuals with severe mental illness. This current review also compared remote and hybrid interventions, the effects of those interventions in metabolic biomarkers as well as in the development of a healthier lifestyle. The main findings included the following: (a) the use of digital devices or strategies might be feasible and useful to reduce sedentary behavior among individuals with severe mental illnesses, 2) most interventions used digital pedometers and mobile phone communication (either text messages or phone calls) as main strategies, 3) all remote interventions and six of nine hybrid interventions found significant outcomes in favor of their interventions. In conclusion, even with a limited number of studies promoting healthier lifestyle through digital interventions among individuals with severe mental illnesses, evidence from studies included in this review showed that they might be useful to improve a healthier lifestyle and increase the frequency of physical activity behavior.


Assuntos
Transtornos Mentais , Comportamento Sedentário , Biomarcadores , Humanos , Transtornos Mentais/terapia , Obesidade , Intervenção Psicossocial
5.
Metab Brain Dis ; 36(3): 509-521, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33411213

RESUMO

Current diagnoses of mood disorders are not cross validated. The aim of the current paper is to explain how machine learning techniques can be used to a) construct a model which ensembles risk/resilience (R/R), adverse outcome pathways (AOPs), staging, and the phenome of mood disorders, and b) disclose new classes based on these feature sets. This study was conducted using data of 67 healthy controls and 105 mood disordered patients. The R/R ratio, assessed as a combination of the paraoxonase 1 (PON1) gene, PON1 enzymatic activity, and early life time trauma (ELT), predicted the high-density lipoprotein cholesterol - paraoxonase 1 complex (HDL-PON1), reactive oxygen and nitrogen species (RONS), nitro-oxidative stress toxicity (NOSTOX), staging (number of depression and hypomanic episodes and suicidal attempts), and phenome (the Hamilton Depression and Anxiety scores and the Clinical Global Impression; current suicidal ideation; quality of life and disability measurements) scores. Partial Least Squares pathway analysis showed that 44.2% of the variance in the phenome was explained by ELT, RONS/NOSTOX, and staging scores. Cluster analysis conducted on all those feature sets discovered two distinct patient clusters, namely 69.5% of the patients were allocated to a class with high R/R, RONS/NOSTOX, staging, and phenome scores, and 30.5% to a class with increased staging and phenome scores. This classification cut across the bipolar (BP1/BP2) and major depression disorder classification and was more distinctive than the latter classifications. We constructed a nomothetic network model which reunited all features of mood disorders into a mechanistically transdiagnostic model.


Assuntos
Aprendizado de Máquina , Transtornos do Humor/diagnóstico , Resiliência Psicológica , Adulto , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/classificação , Transtornos do Humor/metabolismo , Qualidade de Vida , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ideação Suicida
6.
Int J Mol Sci ; 21(8)2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32295201

RESUMO

BACKGROUND: Male breast cancer (BC) is a distinct neoplasm with low but rising incidence, frequently diagnosed as advanced stage disease. Considering the relevance of altered homologous recombination repair (HRR) in male BC, we aimed to explore the biomarker potential of aberrant promoter methylation of ATM, BRCA1, PALB2, RAD51B, and XRCC3. METHODS: Formalin-fixed paraffin-embedded (FFPE) tissue samples from 128 male BC patients, paired adjacent normal tissue and 19 gynecomastia cases were collected and assessed by quantitative methylation-specific PCR (qMSP). Non-parametric tests were used to compare methylation levels between tumor and non-tumor samples and to seek for associations with clinicopathological variables. RESULTS: Only RAD51B and XRCC3 disclosed significant differences between tumor and gynecomastia (p < 0.0001 and p = 0.020, respectively). Assembled in a panel, RAD51B and XRCC3 promoter methylation discriminated male BC from gynecomastia with 91.5% sensitivity, 89.5% specificity, and 91.2% accuracy. Moreover, promoter methylation levels were lower in paired non-tumor tissues, comparing to tumor samples. No associations were found between epigenetic alterations and clinicopathological features, as well as with RAD51 and XRCC3 immunoexpression and methylation levels. CONCLUSION: Quantitative promoter methylation of RAD51B and XRCC3 constitutes a promising and accurate biomarker for male BC. Validation in larger series and in liquid biopsies is warranted to confirm its usefulness in detection and monitoring settings.


Assuntos
Neoplasias da Mama Masculina/genética , Epigênese Genética , Estudos de Associação Genética , Predisposição Genética para Doença , Reparo de DNA por Recombinação , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Neoplasias da Mama Masculina/metabolismo , Neoplasias da Mama Masculina/patologia , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética/métodos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas
7.
Phys Chem Chem Phys ; 20(30): 19811-19818, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30033468

RESUMO

Adsorption of polyions onto charged surfaces has long been recognized as a crucial phenomenon in biological and technological applications. An intuitive model relating polyelectrolyte adsorption with the imposed features of polarizable surfaces of different compositions and charges is proposed based on Monte Carlo simulations using a coarse-grained approach. The excellent performance of the equation allows simultaneously describing a wide range of adsorption regimes and accounting for specific non-monotonic trends. For a constant surface charge density, the surface composition governs adsorption, promoting variations exceeding 100%. Adsorption increases with the number of attractive charges in the surface until reaching a maximum, decreasing thereafter due to the presence of polyanion-like charged particles. The presence of crowders hampers adsorption. These results can be used to efficiently predict and modulate the interaction between charged macromolecules and different substrates with direct implications in de novo designs of vehicles and biomedical devices.

8.
Nutr Res Rev ; 31(1): 85-97, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29191255

RESUMO

Despite the fact that inflammatory bowel disease (IBD) has still no recognised therapy, treatments which have proven at least mildly successful in improving IBD symptoms include anti-inflammatory drugs and monoclonal antibodies targeting pro-inflammatory cytokines. Resveratrol, a natural (poly)phenol found in grapes, red wine, grape juice and several species of berries, has been shown to prevent and ameliorate intestinal inflammation. Here, we discuss the role of resveratrol in the improvement of inflammatory disorders involving the intestinal mucosa. The present review covers three specific aspects of resveratrol in the framework of inflammation: (i) its content in food; (ii) its intestinal absorption and metabolism; and (iii) its anti-inflammatory effects in the intestinal mucosa in vitro and in the very few in vivo studies present to date. Actually, if several studies have shown that resveratrol may down-regulate mediators of intestinal immunity in rodent models, only two groups have performed intervention studies in human subjects using resveratrol as an agent to improve IBD conditions. The effects of resveratrol should be further investigated by conducting well-designed clinical trials, also taking into account different formulations for the delivery of the bioactive compound.


Assuntos
Dieta , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Polifenóis/uso terapêutico , Resveratrol/uso terapêutico , Animais , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Absorção Intestinal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Extratos Vegetais/farmacocinética , Extratos Vegetais/farmacologia , Polifenóis/farmacocinética , Polifenóis/farmacologia , Resveratrol/farmacocinética , Resveratrol/farmacologia
9.
Metab Brain Dis ; 33(4): 1081-1096, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29542039

RESUMO

Early life trauma (ELT) may increase the risk towards bipolar disorder (BD) and major depression (MDD), disorders associated with activated neuro-oxidative and neuro-nitrosative stress (O&NS) pathways. It has remained elusive whether ELTs are associated with O&NS and which ELTs are associated with distinct affective disorder phenotypes. This case-control study examined patients with BD (n = 68) and MDD (n = 37) and healthy controls (n = 66). The Child Trauma Questionnaire (CTQ) was used to assess specific ELT. We measured malondialdehyde (MDA), lipid hydroperoxides (LOOH), superoxide dismutase (SOD), catalase, advanced oxidation protein products (AOPP); NO metabolites (NOx), paraoxonase 1 activity, zinc, albumin, high density lipoprotein cholesterol and -SH groups and computed z-unit weighted composite scores. Physical neglect significantly predicts higher z-unit weighted composite scores of LOOH+SOD, LOOH+SOD+NOx, LOOH+SOD+NOx + MDA and LOOH+SOD+NOx + AOPP. Sexual abuse was associated with a significantly lower composite score of zinc+albumin+SH. Emotional abuse was associated with severity of depression and anxiety, number of depressive and manic episodes, alcohol and hypnotics use, lifetime suicidal behavior and lowered quality of life. Sexual abuse was associated with an increased risk towards BD, but not MDD. ELT, especially physical neglect, may drive increased (nitro-)oxidative stress coupled with lipid and protein oxidation, which - together with emotional abuse - may play a role in severity of illness, lowered quality of life and MDD. ELTs are also associated with the onset of BD, but this link did not appear to be related to activated O&NS pathways. These novel findings deserve confirmation in prospective studies.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Transtorno Bipolar/metabolismo , Transtorno Depressivo/metabolismo , Peroxidação de Lipídeos/fisiologia , Estresse Oxidativo/fisiologia , Qualidade de Vida/psicologia , Tentativa de Suicídio/psicologia , Adulto , Transtorno Bipolar/psicologia , Estudos de Casos e Controles , Catalase/sangue , Estudos Transversais , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Nitrosação/fisiologia , Oxirredução , Recidiva , Ideação Suicida , Superóxido Dismutase/sangue , Inquéritos e Questionários
10.
Phys Chem Chem Phys ; 19(7): 5209-5221, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28149998

RESUMO

Inclusion complexes play a definite role in a variety of applications, ranging from drug solubilization to smart materials. This work presents a series of studies based on molecular dynamics, including potential of mean force calculations, and aiming at understanding the factors that govern inclusion. Naphthalene and its derivatives are used as guests for a common host, ß-cyclodextrin. It is observed that the substitution of naphthalene promotes an increase in the complexation constant (up to 100-fold), irrespective of the nature of the substituent, the latter comprising small hydrophobic and hydrophilic (including charged) groups. It is also seen that entropy does not favor inclusion, the order of magnitude of the binding free energy being given by the enthalpic component, with a dominating guest-host interaction contribution. Desolvation penalizes the inclusion process, and is not observed in the vicinity of the hydrophilic and charged groups, which remain exposed to the solvent. Results suggest that substantial modulation of the inclusion complexes can be achieved imposing different substituents, with direct transposition for the modulation of properties in supramolecular structures based on these complexes.

11.
J Comput Chem ; 36(21): 1579-86, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26096545

RESUMO

The interaction between polyelectrolytes and counterions in confined situations and the mutual relationship between chain conformation and ion condensation is an important issue in several areas. In the biological field, it assumes particular relevance in the understanding of the packaging of nucleic acids, which is crucial in the design of gene delivery systems. In this work, a simple coarse-grained model is used to assess the cooperativity between conformational change and ion condensation in spherically confined backbones, with capsides permeable to the counterions. It is seen that the variation on the degree of condensation depends on counterion valence. For monovalent counterions, the degree of condensation passes through a minimum before increasing as the confining space diminishes. In contrast, for trivalent ions, the overall tendency is to decrease the degree of condensation as the confinement space also decreases. Most of the particles reside close to the spherical wall, even for systems in which the density is higher closer to the cavity center. This effect is more pronounced, when monovalent counterions are present. Additionally, there are clear variations in the charge along the concentric layers that cannot be totally ascribed to polyelectrolyte behavior, as shown by decoupling the chain into monomers. If both chain and counterions are confined, the formation of a counterion rich region immediately before the wall is observed. Spool and doughnut-like structures are formed for stiff chains, within a nontrivial evolution with increasing confinement.

12.
Org Biomol Chem ; 13(34): 9127-39, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26223980

RESUMO

First examples of [8π + 2π] cycloaddition of 16-dehydropregnenolone (16-DPA) acetate with diazafulvenium methides leading to chiral 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridine-fused steroids are reported. These hexacyclic steroids were obtained exclusively or selectively with the approach of the 1,7-dipole by the less hindered α-face of 16-DPA. Quantum chemical calculations at the DFT level were carried out, using the cycloaddition of 1-methyl- and 1-benzyl-diazafulvenium methides with N-phenylmaleimide as model reactions, in order to rationalize the stereochemistry outcome. The results indicate that endo cycloadditions of the more stable dipole conformation, having the 1-substituent pointing outward, are significantly more favorable than the alternative exo cycloaddition.


Assuntos
Compostos Heterocíclicos/síntese química , Imidazóis/química , Indolquinonas/química , Esteroides/síntese química , Catálise , Ciclização , Reação de Cicloadição , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
13.
Neuro Endocrinol Lett ; 36(6): 529-38, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26812289

RESUMO

OBJECTIVE: We examine the relationship between nicotine dependence (ND) and ND-related medical disease and polymorphisms by deletion in genes that encode glutathione S-transferases (GSTs), e.g. GSTM1 and GSTT1. Individuals with homozygous gene deletions show deficiencies in GSTs enzyme activities impairing detoxification. METHODS: This study comprised 182 tobacco users and 182 controls (neversmokers). GSTM1 and GSTT1 polymorphisms were assessed using a Multiplex- PCR based protocol. RESULTS: Logistic regression analyses showed a significant association between ND and the GSTM1 and GSTT1 null genotypes. There were no significant associations between GSTT1, GSTM1 and GSTT1/M1 genetic variants and the Fagerström test for ND, age at onset, smoking cessation or a family history of ND. Patients with ND had increased rates of a family ND history and an increased prevalence of cardiovascular disease, hypertension, and lung disease. The null genotypes were associated with hypertension (i.e. GSTT1 × ND interaction), diabetes type 2 (i.e. GSTM1 × GSTT1 interaction), lung disease (i.e. GSTM1 × ND interaction) and cancer (i.e. GSTT1). The results show that GST null genotypes may confer protection against ND while they increase risk towards ND-related medical disorders.

14.
BMC Genet ; 15: 78, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24968820

RESUMO

BACKGROUND: The aim of this study was to determine if variable number of tandem repeats (VNTR) in the second intron (STin2) of the serotonin transporter (SLC6A4) gene was associated with tobacco use disorder, successful smoking cessation, or smoking characteristics. In this case-control study, patients with current tobacco use disorder, diagnosed according to DSM IV criteria (n = 185), and never-smokers, diagnosed according to CDC criteria (n = 175), were recruited and received 52 weeks of combined pharmacotherapy and cognitive therapy. Successful smoking cessation was defined as exhaled carbon monoxide < 6 ppm. SLC6A4 gene STin2 VNTR polymorphism was assessed using a Multiplex-PCR-based method. At baseline, participants were evaluated using the Fagerström Test for Nicotine Dependence (FTND) and the ASSIST scale. RESULTS: The STin2.12 allele (OR = 2.45; 95% CI = 1.44-4.15, p < 0.001) was associated with an increased risk for tobacco use disorder, while the STin2.10/10 genotype (OR = 0.42; 95% CI 0.25-0.71, p < 0.001) decreased risk. There were no significant associations between tobacco use disorder and the STin2.10 or STin2.9 alleles or the other genotypes (STin2.12/12, 12/10, 12/9, 10/9 or 9/9). There were no significant associations between the STin2 genotypes and alleles and successful smoking cessation, smoking characteristics and increased alcohol or sedative use risk. CONCLUSIONS: Our results suggest that the STin2.10/10 genotype and STin2.12 allele are associated with tobacco use disorder or nicotine dependence, but not with treatment response or severity of dependence. It is hypothesized that the ST2in.12 allele by modulating the metabolism of serotonin may participate in the pathophysiology of tobacco use disorder or nicotine dependence.


Assuntos
Repetições Minissatélites , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Abandono do Hábito de Fumar , Fumar/genética , Tabagismo/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético
15.
Biomacromolecules ; 15(2): 478-91, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24460059

RESUMO

This work aims to shed light on the mechanism of interaction between components of ternary DNA-PEI-Fe(III) complexes, using experimental and theoretical approaches. In the experimental part, the chelation between PEI-Fe(III) was inspected by potentiometry and electrical conductance measurements and the respective importance for the condensation of DNA analyzed. To this end, three different mixing protocols for the components were imposed using different PEIs, branched (bPEI1.2 and bPEI10) and linear (lPEI2.5 and lPEI25). A delay in DNA condensation was observed when PEI and Fe(III) were premixed and then added to DNA. The set of observations was complemented by determination of the amount of Fe(III) included in the polyplexes, which was found to be dependent on the order of mixture and on the type of PEI used, decreasing with intrinsic PEI condensation efficiency. Overall, a coherent picture in which Fe(III) compensates PEI, probably modulating the respective charge, emerges. Some points arisen from the experimental part were rationalized using Monte Carlo simulations. Different architectured polycation (PC) chains were modeled and an interaction between PC and multivalent ions, mimicking the chelation of Fe(III) by the PEI, was imposed. It was found that chelation enhances polyanion (PA) compaction, irrespective of the PC architecture and charge density. The amount of multivalent ions in each polyplex compensates the negative charge unbalanced by the PC. The charge density and the ability of chelation of each PC dictate the disposition of each condensing agent along the PA backbone, and their coexistence strengthens PA compaction. The deep understanding of these ternary mixtures is a step forward in the optimization of such systems for application in gene delivery.


Assuntos
DNA/química , Compostos Férricos/química , Polietilenoimina/química , Método de Monte Carlo
16.
J Org Chem ; 79(21): 10456-65, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25310009

RESUMO

The reactivity of nitrosoalkenes toward dipyrromethanes, pyrrole, and 2,5-dimethylpyrrole is described. 1-(p-Bromophenyl)nitrosoethylene shows a different chemical behavior with these heterocycles than the previously reported reactions of ethyl nitrosoacrylate, which proceeds via a Diels-Alder reaction. 1-(p-Bromophenyl)nitrosoethylene reacts with dipyrromethanes and pyrrole to afford two isomeric oximes via conjugate addition followed by rearomatization of the pyrrole unit. On the other hand, this nitrosoalkene reacts with 2,5-dimethylpyrrole through an initial conjugate addition followed by intramolecular O- and N-nucleophilic addition with the formation of the corresponding bicyclic oxazine and five-membered cyclic nitrone, respectively. Quantum chemical calculations, at the DFT level of theory, indicate that the barriers associated with the Diels-Alder reactions of ethyl nitrosoacrylate are over 30 kJ/mol lower than those that would be required for the cycloadditions of 1-(p-bromophenyl)nitrosoethylene. Thus, calculations predict that the Diels-Alder reaction is privileged in the case of ethyl nitrosoacrylate and point to a different reaction pathway for 1-(p-bromophenyl)nitrosoethylene, corroborating the experimental findings.

17.
Colloids Surf B Biointerfaces ; 241: 113983, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38850741

RESUMO

Glioblastoma (GB) is one of the most lethal types of neoplasms with unique anatomic, physiologic, and pathologic features that usually persist after exposure to standard therapeutic modalities. It is biologically aggressive, and the existence of the blood-brain barrier (BBB) limits the efficacy of standard therapies. In this work, we hypothesize the potential of surface-functionalized ultra-small nanostructured lipid carriers (usNLCs) with charge-switchable cell-penetrating peptides (CPPs) to overcome this biological barrier and improve targeted delivery to brain tumor tissues. The big question is: what is the potential of CPPs in directing nanoparticles toward brain tumor tissue? To answer this question, the usNLCs were functionalized with distinct biomolecules [five CPPs, c(RGDfK) and transferrin, Tf] through electrostatic interaction and its ability as a targeting approach to BBB (HBMEC) and glioma cells (U87 cells) evaluated in terms of physicochemical properties, cellular uptake, permeability in a 2D-BBB model, and tumor growth inhibition. Monte Carlo simulations elucidated CPP adsorption patterns. The permeability studies revealed that targeted usNLCs, especially usNLCsTf and usNLCsCPP4, exhibited an increased permeability coefficient compared to the non-targeted usNLCs. Functionalized usNLCs evidenced enhanced uptake in BBB cells, with smaller CPPs showing higher internalization (CPP1 and CPP2). Similarly, functionalized usNLCs exhibited more significant cytotoxicity in glioma cells, with specific CPPs promoting favorable internalization. Analysis of the endocytic pathway indicated that usNLCsCPPs were mainly internalized by direct translocation and caveolae-mediated endocytosis. Optimal usNLCs with dual targeting capabilities to both BBB and GB cells provide a promising therapeutic strategy for GB.

18.
Cell Death Discov ; 10(1): 1, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172127

RESUMO

Alterations in the epigenetic machinery in both tumor and immune cells contribute to bladder cancer (BC) development, constituting a promising target as an alternative therapeutic option. Here, we have explored the effects of a novel histone deacetylase (HDAC) inhibitor CM-1758, alone or in combination with immune checkpoint inhibitors (ICI) in BC. We determined the antitumor effects of CM-1758 in various BC cell lines together with the induction of broad transcriptional changes, with focus on the epigenetic regulation of PD-L1. Using an immunocompetent syngeneic mouse model of metastatic BC, we studied the effects of CM-1758 alone or in combination with anti-PD-L1 not only on tumor cells, but also in the tumor microenvironment. In vitro, we found that CM-1758 has cytotoxic and cytostatic effects either by inducing apoptosis or cell cycle arrest in BC cells at low micromolar levels. PD-L1 is epigenetically regulated by histone acetylation marks and is induced after treatment with CM-1758. We also observed that treatment with CM-1758 led to an important delay in tumor growth and a higher CD8 + T cell tumor infiltration. Moreover, anti-PD-L1 alone or in combination with CM-1758 reprogramed macrophage differentiation towards a M1-like polarization state and increased of pro-inflammatory cytokines systemically, yielding potential further antitumor effects. Our results suggest the possibility of combining HDAC inhibitors with immunotherapies for the management of advanced metastatic BC.

19.
J Comput Chem ; 34(14): 1198-209, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-23386422

RESUMO

Adsorption phenomena are relevant in a wide variety of subjects, from biophysics to technological applications. Different aspects, such as molecular recognition, multilayer deposition, and dynamics of polymer adsorption have been addressed. The methodologies used range from analytical and numerical methods to molecular dynamics or Monte Carlo simulations. In this work, a coarse-grained model is used to explore the adsorption of charged backbones to oppositely charged regions of a surface. These regions encompass those small enough to prevent complete adsorption, but extend to surfaces sufficiently large to promote adsorption with minimal effect on the three-dimensional conformation in bulk. Apart from the different surface areas explored, variations on the surface charge density, polyelectrolyte chain length, and chain stiffness were also considered. The degree of compaction of the polyelectrolyte, on adsorption, is different from that found in the bulk. Also, results indicate an nonuniform adsorption pattern on regularly charged surfaces.


Assuntos
Polímeros/química , Adsorção , Modelos Químicos , Conformação Molecular , Simulação de Dinâmica Molecular , Método de Monte Carlo , Eletricidade Estática , Propriedades de Superfície
20.
J Sex Med ; 10(4): 1136-45, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23350632

RESUMO

INTRODUCTION.: Evidence is accumulating to support the presence of erectile dysfunction in patients with schizophrenia. This dysregulation may be amenable to therapeutic intervention to improve adherence and quality of life of patients who suffer from schizophrenia and schizoaffective disorders. AIM.: We aimed to evaluate the use of adjunctive medication lodenafil for the treatment of erectile dysfunction in outpatients with schizophrenia and spectrum. METHODS.: The design was a randomized, double-blind, crossover, placebo-controlled trial with lodenafil and it was carried at the Schizophrenia Outpatients Program. MAIN OUTCOME MEASURES.: The measures used to assess sexual dysfunction were Arizona Sexual Experiences Scale (ASEX) and International Index of Erectile Function (IIEF). The Positive and Negative Syndrome Scale (PANSS) and the Quality of Life Scale (QLS) were also used. The measures included the levels of prolactin, estradiol, luteinizing hormone, sex hormone-binding globulin, free testosterone, and total testosterone at baseline and end point. Lodenafil and placebo pills were used by the patients for 16 weeks. RESULTS.: Fifty male outpatients fulfilled the criteria and 94% of the participants completed the study. Lodenafil and placebo produced improvement in ASEX, IIEF scale, PANSS, and QLS, and there was no statistical difference between lodenafil and placebo groups in all sexual domains in the results of PANSS and QLS and in the results of hormone levels. CONCLUSION.: These results indicate that both lodenafil and placebo were effective in the treatment of erectile dysfunction for schizophrenia. Placebo effect is very important in patients with schizophrenia and this study showed the importance of discussing sexuality and trying to treat these patients. Further studies designed to test treatments of erectile dysfunction in patients who suffer from schizophrenia are necessary.


Assuntos
Carbonatos/uso terapêutico , Disfunção Erétil/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Esquizofrenia/complicações , Adulto , Assistência Ambulatorial , Análise de Variância , Estudos Cross-Over , Método Duplo-Cego , Disfunção Erétil/complicações , Estradiol/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Prolactina/sangue , Qualidade de Vida , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue
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