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1.
Pharmacopsychiatry ; 57(3): 160-168, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447959

RESUMO

Dementia, with loss of memory, cognitive abilities, and independent daily functioning, is increasing worldwide, related to an aging population. Currently, there is no curative treatment for dementia. Treatment of the frequently occurring behavioral and psychological symptoms of dementia (BPSD) is partially effective and associated with significant side effects. Cannabinoids are lipophilic molecules acting on the CB1 end CB2 receptors, essential for main biological processes such as sleep, appetite, memory, and pain. Cannabinoids might have a positive impact on amyloid formation in Alzheimer's disease, the main form of dementia, and on BPSD symptoms. Most knowledge currently concerns delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). In the context of dementia and BPSD, THC might be beneficial for associated spasticity and possible pain or lack of appetite and CBD probably works better on sleep, agitation, and anxiety. This overview of prospective clinical studies and randomized clinical trials, published between 2005 and April 2023, using cannabinoids for BPSD suggests that older studies using low-dose oral synthetic THC showed no positive results. Still, more recent studies using THC/CBD-based oral medication at higher doses show promising results and are feasible and safe in this elderly polymedicated population. Several RCTs are ongoing and planned worldwide, and we hope other trials will follow to establish clinical efficiency and optimal dosing, as well as other outcomes such as deprescribing other medications and facilitation of care. We suggest that researchers also address the more sociological aspects of prescribing cannabinoids for dementia and BPSD in their specific context.


Assuntos
Canabinoides , Demência , Humanos , Demência/tratamento farmacológico , Canabinoides/uso terapêutico , Sintomas Comportamentais/tratamento farmacológico , Canabidiol/uso terapêutico , Dronabinol/uso terapêutico
2.
Molecules ; 29(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38930867

RESUMO

Solid-phase microextraction (SPME) has been widely proposed for the extraction, clean-up, and preconcentration of analytes of environmental concern. Enrichment capabilities, preconcentration efficiency, sample throughput, and selectivity in extracting target compounds greatly depend on the materials used as SPME coatings. Supramolecular materials have emerged as promising porous coatings to be used for the extraction of target compounds due to their unique selectivity, three-dimensional framework, flexible design, and possibility to promote the interaction between the analytes and the coating by means of multiple oriented functional groups. The present review will cover the state of the art of the last 5 years related to SPME coatings based on metal organic frameworks (MOFs), covalent organic frameworks (COFs), and supramolecular macrocycles used for environmental applications.

3.
Anal Bioanal Chem ; 415(1): 119-135, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36367573

RESUMO

Traditional techniques for food analysis are based on off-line laboratory methods that are expensive and time-consuming and often require qualified personnel. Despite the high standards of accuracy and metrological traceability, these well-established methods do not facilitate real-time process monitoring and timely on-site decision-making as required for food safety and quality control. The future of food testing includes rapid, cost-effective, portable, and simple methods for both qualitative screening and quantification of food contaminants, as well as continuous, real-time measurement in production lines. Process automatization through process analytical technologies (PAT) is an increasing trend in the food industry as a way to achieve improved product quality, safety, and consistency, reduced production cycle times, minimal product waste or reworks, and the possibility for real-time product release. Novel methods of analysis for point-of-need (PON) screening could greatly improve food testing by allowing non-experts, such as consumers, to test in situ food products using portable instruments, smartphones, or even visual naked-eye inspections, or farmers and small producers to monitor products in the field. This requires the attention of the research community and devices manufacturers to ensure reliability of measurement results from PAT strategy and PON tests through the demonstration and critical evaluation of performance characteristics. The fitness for purpose of methods in real-life conditions is a priority that should not be overlooked in order to maintain an effective and harmonized food safety policy.


Assuntos
Inocuidade dos Alimentos , Reprodutibilidade dos Testes , Inocuidade dos Alimentos/métodos , Controle de Qualidade , Padrões de Referência
4.
Ear Hear ; 44(3): 530-543, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36378104

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the benefits of bilateral implantation for bone-anchored hearing system (BAHS) users in terms of spatial resolution abilities and auditory memory for speech. DESIGN: This is a prospective, single-center, comparative, single-blinded study where the listeners served as their own control. Twenty-four experienced bone-anchored users with a bilateral conductive or mixed hearing loss participated in the study. After fitting the listeners unilaterally and bilaterally with BAHS sound processor(s) (Ponto 3 SuperPower), spatial resolution was estimated by measuring the minimum audible angle (MAA) to achieve an 80% correct response via a two-alternative-forced choice task (right-left discrimination of noise bursts) in two conditions: both sound processors active (bilateral condition) and only one sound processor active (unilateral condition). In addition, a memory recall test, the Sentence-final Word Identification and Recall (SWIR) test was performed with five lists of seven sentences for each of the two conditions (unilateral and bilateral). Self-reported performance in everyday life with the listener's own sound processors was also evaluated via a questionnaire (the abbreviated version of the Speech, Spatial and Qualities of Hearing scale). RESULTS: The MAA to discriminate noise bursts improved significantly from 75.04° in the unilateral condition to 3.61° in the bilateral condition ( p < 0.0001). The average improvement in performance was 54.28°. The SWIR test results showed that the listeners could recall, on average, 55.03% of the last words in a list of seven sentences in the unilateral condition and 57.23% in the bilateral condition. While the main effect of condition was not significant, there was a significant interaction between condition and repetition (list), revealing a significantly higher recall performance in the bilateral condition than in the unilateral condition for the second repetition/list out of five (10.2% difference; p = 0.022). Self-reported performance with bilateral BAHS obtained via the Speech, Spatial and Qualities of Hearing scale questionnaire was, on average, 4.4 for speech, 3.7 for spatial, and 5.1 for qualities of hearing. There was no correlation between self-reported performance in everyday life and bilateral performance in the MAA test, while significant correlations were obtained between self-reported performance and recall performance in the SWIR test. CONCLUSIONS: These results showed a large benefit in spatial resolution for users with symmetric BC thresholds when being fitted with two BAHS, although their self-reported performance with bilateral BAHS in everyday life was rather low. In addition, there was no overall benefit of bilateral fitting on memory for speech, despite observing a benefit in one out of five repetitions of the SWIR test. Performance in the SWIR test was correlated with the users' self-reported performance in everyday life, such that users with higher recall ability reported to achieve better performance in real life. These findings highlight the advantages of bilateral fitting on spatial resolution, although bilaterally fitted BAHS users continue to experience some difficulties in their daily lives, especially when locating sounds, judging distance and movement. More research is needed to support a higher penetration of bilateral BAHS treatment for bilateral conductive and mixed hearing losses.


Assuntos
Auxiliares de Audição , Perda Auditiva , Percepção da Fala , Humanos , Audição , Estudos Prospectivos , Fala
5.
Environ Res ; 235: 116667, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37453508

RESUMO

Phthalate esters (PAEs) due to their ability to leach from plastics, widely used in our daily life, are intensely accumulating in wastewater water treatment plants (WWTP) and rivers, before being exported to downstream situated estuarine systems. This study aimed to investigate the external sources of eight plasticizers to the largest European lagoon (the Curonian Lagoon, south-east Baltic Sea), focusing on their seasonal variation and transport behaviour through the partitioning between dissolved and particulate phases. The obtained results were later combined with hydrological inputs at the inlet and outlet of the lagoon to estimate system role in regulating the transport of pollutants to the sea. Plasticizers were detected during all sampling events with a total concentration ranging from 0.01 to 6.17 µg L-1. Di(2-ethylhexyl) phthalate (DEHP) was the most abundant PAEs and was mainly found attached to particulate matter, highlighting the importance of this matrix in the transport of such contaminant. Dibutyl phthalate (DnBP) and diisobutyl phthalate (DiBP) were the other two dominant PAEs found in the area, mainly detected in dissolved phase. Meteorological conditions appeared to be an important factor regulating the distribution of PAEs in environment. During the river ice-covered season, PAEs concentration showed the highest value suggesting the importance of ice in the retention of PAEs. While heavy rainfall impacts the amount of water delivered to WWTP, there is an increase of PAEs concentration supporting the hypothesis of their transport via soil leaching and infiltration into wastewater networks. Rainfall could also be a direct source of PAEs to the lagoon resulting in net surplus export of PAEs to the Baltic Sea.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Plastificantes/análise , Estações do Ano , Águas Residuárias , Gelo , Ésteres , China
6.
Organ Res Methods ; 26(3): 524-565, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37342836

RESUMO

Relational event models expand the analytical possibilities of existing statistical models for interorganizational networks by: (i) making efficient use of information contained in the sequential ordering of observed events connecting sending and receiving units; (ii) accounting for the intensity of the relation between exchange partners, and (iii) distinguishing between short- and long-term network effects. We introduce a recently developed relational event model (REM) for the analysis of continuously observed interorganizational exchange relations. The combination of efficient sampling algorithms and sender-based stratification makes the models that we present particularly useful for the analysis of very large samples of relational event data generated by interaction among heterogeneous actors. We demonstrate the empirical value of event-oriented network models in two different settings for interorganizational exchange relations-that is, high-frequency overnight transactions among European banks and patient-sharing relations within a community of Italian hospitals. We focus on patterns of direct and generalized reciprocity while accounting for more complex forms of dependence present in the data. Empirical results suggest that distinguishing between degree- and intensity-based network effects, and between short- and long-term effects is crucial to our understanding of the dynamics of interorganizational dependence and exchange relations. We discuss the general implications of these results for the analysis of social interaction data routinely collected in organizational research to examine the evolutionary dynamics of social networks within and between organizations.

7.
Small ; 18(1): e2104946, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34755446

RESUMO

The removal of toxic and carcinogenic polycyclic aromatic hydrocarbons (PAHs) from water is one of the most intractable environmental problems nowadays, because of their resistance to remediation. This work introduces a highly efficient, regenerable membrane for the removal of PAHs from water, featuring excellent filter performance and pH-driven release, thanks to the integration of a cavitand receptor in electrospun polyacrylonitrile (PAN) fibers. The role of the cavitand receptor is to act as molecular gripper for the uptake/release of PAHs. To this purpose, the deep cavity cavitand BenzoQxCav is designed and synthetized and its molecular structure is elucidated via X-Ray diffraction. The removal efficiency of the new adsorbent material toward the 16 priority PAHs is demonstrated via GC-MS analyses at ng L-1 concentration. A removal efficiency in the 32%, to 99% range is obtained. The regeneration of the membrane is performed by exploiting the pH-driven conformational switching of the cavitand between the vase form, where the PAHs uptake takes place, to the kite one, where the PAHs release occurs. The absorbance and regeneration capability of the membrane are successfully tested in four uptake/release cycles and the morphological stability.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Éteres Cíclicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Resorcinóis , Água
8.
PLoS Pathog ; 16(10): e1008882, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33007046

RESUMO

Neisseria meningitidis serogroup B (MenB) is the leading cause of meningococcal meningitis and sepsis in industrialized countries, with the highest incidence in infants and adolescents. Two recombinant protein vaccines that protect against MenB are now available (i.e. 4CMenB and MenB-fHbp). Both vaccines contain the Factor H Binding Protein (fHbp) antigen, which can bind the Human Factor H (fH), the main negative regulator of the alternative complement pathway, thus enabling bacterial survival in the blood. fHbp is present in meningococcal strains as three main variants which are immunologically distinct. Here we sought to obtain detailed information about the epitopes targeted by anti-fHbp antibodies induced by immunization with the 4CMenB multicomponent vaccine. Thirteen anti-fHbp human monoclonal antibodies (mAbs) were identified in a library of over 100 antibody fragments (Fabs) obtained from three healthy adult volunteers immunized with 4CMenB. Herein, the key cross-reactive mAbs were further characterized for antigen binding affinity, complement-mediated serum bactericidal activity (SBA) and the ability to inhibit binding of fH to live bacteria. For the first time, we identified a subset of anti-fHbp mAbs able to elicit human SBA against strains with all three variants and able to compete with human fH for fHbp binding. We present the crystal structure of fHbp v1.1 complexed with human antibody 4B3. The structure, combined with mutagenesis and binding studies, revealed the critical cross-reactive epitope. The structure also provided the molecular basis of competition for fH binding. These data suggest that the fH binding site on fHbp v1.1 can be accessible to the human immune system upon immunization, enabling elicitation of human mAbs broadly protective against MenB. The novel structural, biochemical and functional data are of great significance because the human vaccine-elicited mAbs are the first reported to inhibit the binding of fH to fHbp, and are bactericidal with human complement. Our studies provide molecular insights into the human immune response to the 4CMenB meningococcal vaccine and fuel the rationale for combined structural, immunological and functional studies when seeking deeper understanding of the mechanisms of action of human vaccines.


Assuntos
Anticorpos/imunologia , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Meningite Meningocócica/imunologia , Vacinas Meningocócicas/administração & dosagem , Neisseria meningitidis/imunologia , Adulto , Anticorpos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Fator H do Complemento/imunologia , Fator H do Complemento/metabolismo , Humanos , Meningite Meningocócica/metabolismo , Meningite Meningocócica/microbiologia , Meningite Meningocócica/prevenção & controle
9.
Eur J Neurol ; 29(8): 2493-2498, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35384164

RESUMO

BACKGROUND AND PURPOSE: Oropharyngeal dysphagia is generally recognized to increase the risk of malnutrition; however, its role in patients with neurodegenerative disease has yet to be determined. This cross-sectional study aimed to investigate the impact of swallowing function on malnutrition risk in patients with neurodegenerative diseases. METHODS: Patients with oral nutrition and diagnosis of Huntington disease (HD), Parkinson disease (PD), or amyotrophic lateral sclerosis (ALS) were recruited. Demographic and clinical data were collected. The swallowing assessment included a fiberoptic endoscopic evaluation of swallowing, an oral phase assessment, and a meal observation scored with the Mealtime Assessment Scale (MAS). Malnutrition risk was assessed with the Mini Nutritional Assessment. RESULTS: Overall, 148 patients were recruited (54 HD, 33 PD, and 61 ALS). One hundred (67.6%) patients were considered at risk of malnutrition. In the multivariate analysis, age ≥ 65 years (odds ratio [OR] = 3.16, p = 0.014), disease severity (moderate vs mild OR = 3.89, severe vs mild OR = 9.71, p = 0.003), number of masticatory cycles (OR = 1.03, p = 0.044), and MAS safety (OR = 1.44, p = 0.016) were significantly associated with malnutrition risk. CONCLUSIONS: Prolonged oral phase and signs of impaired swallowing safety during meals, together with older age and disease severity, are independent predictors of malnutrition risk in neurodegenerative diseases. This study broadens the focus on dysphagia, stressing the importance of early detection not only of pharyngeal signs, but also of oral phase impairment and meal difficulties through a multidimensional swallowing assessment.


Assuntos
Esclerose Lateral Amiotrófica , Transtornos de Deglutição , Doença de Huntington , Desnutrição , Doenças Neurodegenerativas , Doença de Parkinson , Idoso , Estudos Transversais , Deglutição , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Humanos , Desnutrição/complicações , Desnutrição/epidemiologia , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/epidemiologia , Doença de Parkinson/complicações
10.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500684

RESUMO

Methyl farnesoate (MF), a juvenile hormone, can influence phenotypic traits and stimulates male production in daphnids. MF is produced endogenously in response to stressful conditions, but it is not known whether this hormone can also be released into the environment to mediate stress signaling. In the present study, for the first time, a reliable solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) method was developed and validated for the ultra-trace analysis of MF released in growth medium by Daphnia pulex maintained in presence of crowding w/o MK801, a putative upstream inhibitor of MF endogenous production. Two different clonal lineages, I and S clones, which differ in the sensitivity to the stimuli leading to male production, were also compared. A detection limit of 1.3 ng/L was achieved, along with good precision and trueness, thus enabling the quantitation of MF at ultra-trace level. The achieved results demonstrated the release of MF by both clones at the 20 ng/L level in control conditions, whereas a significant decrease in the presence of crowding was assessed. As expected, a further reduction was obtained in the presence of MK801. These findings strengthen the link between environmental stimuli and the MF signaling pathway. Daphnia pulex, by releasing the juvenile hormone MF in the medium, could regulate population dynamics by means of an autoregulatory feedback loop that controls the intra- and extra-individual-level release of MF produced by endogenous biosynthesis.


Assuntos
Daphnia , Ácidos Graxos Insaturados , Animais , Masculino , Daphnia/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Graxos Insaturados/farmacologia , Hormônios Juvenis , Microextração em Fase Sólida/métodos
11.
FASEB J ; 34(8): 10329-10341, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32725956

RESUMO

The classical complement pathway is triggered when antigen-bound immunoglobulins bind to C1q through their Fc region. While C1q binds to a single Fc with low affinity, a higher avidity stable binding of two or more of C1q globular heads initiates the downstream reactions of the complement cascade ultimately resulting in bacteriolysis. Synergistic bactericidal activity has been demonstrated when monoclonal antibodies recognize nonoverlapping epitopes of the same antigen. The aim of the present work was to investigate the synergistic effect between antibodies directed toward different antigens. To this purpose, we investigated the bactericidal activity induced by combinations of monoclonal antibodies (mAbs) raised against factor H-binding protein (fHbp) and Neisserial Heparin-Binding Antigen (NHBA), two major antigens included in Bexsero, the vaccine against Meningococcus B, for prevention from this devastating disease in infants and adolescents. Collectively, our results show that mAbs recognizing different antigens can synergistically activate complement even when each single Mab is not bactericidal, reinforcing the evidence that cooperative immunity induced by antigen combinations can represent a remarkable added value of multicomponent vaccines. Our study also shows that the synergistic effect of antibodies is modulated by the nature of the respective epitopes, as well as by the antigen density on the bacterial cell surface.


Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Proteínas do Sistema Complemento/imunologia , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Transporte/imunologia , Fator H do Complemento/imunologia , Epitopos/imunologia , Neisseria meningitidis/imunologia , Ensaios de Anticorpos Bactericidas Séricos/métodos
12.
Andrologia ; 53(1): e13844, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33125748

RESUMO

Varicocele is the primary cause of male infertility and the interests of research about varicocele have changed in the last years. The aim of the study was to analyse how topics of interests about varicocele have changed in the last two decades. Literature about paediatric varicocele between 2000 and 2018 was reviewed, and the subjects of the articles were analysed, selecting the main and secondary topics of each article. A study of their prevalence over the years was performed. In the research, 625 articles were found but only 169 provided data in the paediatric age. The total percentage of exclusively paediatric works was 27.04%, being above average in Europe, North and South America. The main subject both for Europe and North America was surgical technique, while for Asia it was videolaparoscopy. The main issue in South America was fertility; Africa and Oceania do not have enough publications to make statistics. Paediatric articles account for less than one-third of overall articles. The first interest of research is surgical technique. In Europe, the topics seem to exclude fertility potential.


Assuntos
Infertilidade Masculina , Varicocele , África , Ásia , Criança , Humanos , Masculino , América do Sul , Varicocele/epidemiologia , Varicocele/cirurgia
13.
Angew Chem Int Ed Engl ; 60(18): 10194-10202, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33512039

RESUMO

Metal-organic frameworks (MOFs) give the opportunity of confining guest molecules into their pores even by a post-synthetic protocol. PUM168 is a Zn-based MOF characterized by microporous cavities that allows the encapsulation of a significant number of guest molecules. The pores engineered with different binding sites show a remarkable guest affinity towards a series of natural essential oils components, such as eugenol, thymol and carvacrol, relevant for environmental applications. Exploiting single crystal X-ray diffraction, it was possible to step-wisely monitor the rather complex three-components guest exchange process involving dimethylformamide (DMF, the pristine solvent) and binary mixtures of the flavoring agents. A picture of the structural evolution of the DMF-to-guest replacement occurring inside the MOF crystal was reached by a detailed single-crystal-to-single-crystal monitoring. The relation of the supramolecular arrangement in the pores with selective guests release was then investigated as a function of time and temperature by static headspace GC-MS analysis.

14.
FASEB J ; 33(11): 12099-12111, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31442074

RESUMO

The 4 component meningococcus B vaccine (4CMenB) vaccine is the first vaccine containing recombinant proteins licensed for the prevention of invasive meningococcal disease caused by meningococcal serogroup B strains. 4CMenB contains 3 main recombinant proteins, including the Neisseria meningitidis factor H binding protein (fHbp), a lipoprotein able to bind the human factor H. To date, over 1000 aa sequences of fHbp have been identified, and they can be divided into variant groups 1, 2, and 3, which are usually not crossprotective. Nevertheless, previous characterizations of a small set (n = 10) of mAbs generated in humans after 4CMenB immunization revealed 2 human Fabs (huFabs) (1A12, 1G3) with some crossreactivity for variants 1, 2, and 3. This unexpected result prompted us to examine a much larger set of human mAbs (n = 110), with the aim of better understanding the extent and nature of crossreactive anti-fHbp antibodies. In this study, we report an analysis of the human antibody response to fHbp, by the characterization of 110 huFabs collected from 3 adult vaccinees during a 6-mo study. Although the 4CMenB vaccine contains fHbp variant 1, 13 huFabs were also found to be crossreactive with variants 2 and 3. The crystal structure of the crossreactive huFab 1E6 in complex with fHbp variant 3 was determined, revealing a novel, highly conserved epitope distinct from the epitopes recognized by 1A12 or 1G3. Further, functional characterization shows that human mAb 1E6 is able to elicit rabbit, but not human, complement-mediated bactericidal activity against meningococci displaying fHbp from any of the 3 different variant groups. This functional and structural information about the human antibody response upon 4CMenB immunization contributes to further unraveling the immunogenic properties of fHbp. Knowledge gained about the epitope profile recognized by the human antibody repertoire could guide future vaccine design.-Bianchi, F., Veggi, D., Santini, L., Buricchi, F., Bartolini, E., Lo Surdo, P., Martinelli, M., Finco, O., Masignani, V., Bottomley, M. J., Maione, D., Cozzi, R. Cocrystal structure of meningococcal factor H binding protein variant 3 reveals a new crossprotective epitope recognized by human mAb 1E6.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Fator H do Complemento/imunologia , Epitopos/imunologia , Vacinas Meningocócicas/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fator H do Complemento/genética , Fator H do Complemento/metabolismo , Cristalografia por Raios X , Epitopos/genética , Epitopos/metabolismo , Variação Genética , Humanos , Infecções Meningocócicas/microbiologia , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/administração & dosagem , Modelos Moleculares , Neisseria meningitidis/efeitos dos fármacos , Neisseria meningitidis/imunologia , Neisseria meningitidis/fisiologia , Ligação Proteica , Conformação Proteica
15.
Anal Bioanal Chem ; 412(17): 3967-3973, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32385578

RESUMO

An outlook on the current status and trends in desorption electrospray ionization-mass spectrometry (DESI-MS), one of the most common spray-based techniques for ambient ionization, is given with a focus on the main advances recently achieved or still in progress regarding studies of surface properties affecting the signal stability and efficiency of the DESI process. Future directions that the field may take in the years to come are discussed, with particular focus on bioanalytical research.

16.
Ear Hear ; 40(5): 1220-1232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30807542

RESUMO

OBJECTIVES: The aim of this study was to compare listening effort, as estimated via pupillary response, during a speech-in-noise test in bone-anchored hearing system (BAHS) users wearing three different sound processors. The three processors, Ponto Pro (PP), Ponto 3 (P3), and Ponto 3 SuperPower (P3SP), differ in terms of maximum force output (MFO) and MFO algorithm. The hypothesis was that listeners would allocate lower listening effort with the P3SP than with the PP, as a consequence of a higher MFO and, hence, fewer saturation artifacts in the signal. DESIGN: Pupil dilations were recorded in 21 BAHS users with a conductive or mixed hearing loss, during a speech-in-noise test performed at positive signal-to-noise ratios (SNRs), where the speech and noise levels were individually adjusted to lead to 95% correct intelligibility with the PP. The listeners had to listen to a sentence in noise, retain it for 3 seconds and then repeat it, while an eye-tracking camera recorded their pupil dilation. The three sound processors were tested in random order with a single-blinded experimental design. Two conditions were performed at the same SNR: Condition 1, where the speech level was designed to saturate the PP but not the P3SP, and condition 2, where the overall sound level was decreased relative to condition 1 to reduce saturation artifacts. RESULTS: The P3SP led to higher speech intelligibility than the PP in both conditions, while the performance with the P3 did not differ from the performance with the PP and the P3SP. Pupil dilations were analyzed in terms of both peak pupil dilation (PPD) and overall pupil dilation via growth curve analysis (GCA). In condition 1, a significantly lower PPD, indicating a decrease in listening effort, was obtained with the P3SP relative to the PP. The PPD obtained with the P3 did not differ from the PPD obtained with the other two sound processors. In condition 2, no difference in PPD was observed across the three processors. The GCA revealed that the overall pupil dilation was significantly lower, in both conditions, with both the P3SP and the P3 relative to the PP, and, in condition 1, also with the P3SP relative to the P3. CONCLUSIONS: The overall effort to process a moderate to loud speech signal was significantly reduced by using a sound processor with a higher MFO (P3SP and P3), as a consequence of fewer saturation artifacts. These findings suggest that sound processors with a higher MFO may help BAHS users in their everyday listening scenarios, in particular in noisy environments, by improving sound quality and, thus, decreasing the amount of cognitive resources utilized to process incoming speech sounds.


Assuntos
Auxiliares de Audição , Perda Auditiva Condutiva/reabilitação , Perda Auditiva Condutiva-Neurossensorial Mista/reabilitação , Processamento de Sinais Assistido por Computador/instrumentação , Percepção da Fala , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Perda Auditiva Condutiva/fisiopatologia , Perda Auditiva Condutiva/psicologia , Perda Auditiva Condutiva-Neurossensorial Mista/fisiopatologia , Perda Auditiva Condutiva-Neurossensorial Mista/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Ruído , Pupila/fisiologia , Razão Sinal-Ruído , Adulto Jovem
17.
Neuroimage ; 163: 398-412, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28774646

RESUMO

Musicians are highly trained to discriminate fine pitch changes but the neural bases of this ability are poorly understood. It is unclear whether such training-dependent differences in pitch processing arise already in the subcortical auditory system or are linked to more central stages. To address this question, we combined psychoacoustic testing with functional MRI to measure cortical and subcortical responses in musicians and non-musicians during a pitch-discrimination task. First, we estimated behavioral pitch-discrimination thresholds for complex tones with harmonic components that were either resolved or unresolved in the auditory system. Musicians outperformed non-musicians, showing lower pitch-discrimination thresholds in both conditions. The same participants underwent task-related functional MRI, while they performed a similar pitch-discrimination task. To account for the between-group differences in pitch-discrimination, task difficulty was adjusted to each individual's pitch-discrimination ability. Relative to non-musicians, musicians showed increased neural responses to complex tones with either resolved or unresolved harmonics especially in right-hemispheric areas, comprising the right superior temporal gyrus, Heschl's gyrus, insular cortex, inferior frontal gyrus, and in the inferior colliculus. Both subcortical and cortical neural responses predicted the individual pitch-discrimination performance. However, functional activity in the inferior colliculus correlated with differences in pitch discrimination across all participants, but not within the musicians group alone. Only neural activity in the right auditory cortex scaled with the fine pitch-discrimination thresholds within the musicians. These findings suggest two levels of neuroplasticity in musicians, whereby training-dependent changes in pitch processing arise at the collicular level and are preserved and further enhanced in the right auditory cortex.


Assuntos
Córtex Auditivo/fisiologia , Discriminação da Altura Tonal/fisiologia , Adulto , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Plasticidade Neuronal , Adulto Jovem
18.
Chemistry ; 22(10): 3312-3319, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26762207

RESUMO

Two novel triptycene quinoxaline cavitands (DiTriptyQxCav and MonoTriptyQxCav) have been designed, synthesized, and applied in the supramolecular detection of benzene, toluene, ethylbenzene, and xylenes (BTEX) in air. The complexation properties of the two cavitands towards aromatics in the solid state are strengthened by the presence of the triptycene moieties at the upper rim of the tetraquinoxaline walls, promoting the confinement of the aromatic hydrocarbons within the cavity. The two cavitands were used as fiber coatings for solid-phase microextraction (SPME) BTEX monitoring in air. The best performances in terms of enrichment factors, selectivity, and LOD (limit of detection) values were obtained by using the DiTriptyQxCav coating. The corresponding SPME fiber was successfully tested under real urban monitoring conditions, outperforming the commercial divinylbenzene-Carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fiber in BTEX adsorption.

19.
Bioorg Med Chem ; 24(8): 1619-36, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26951894

RESUMO

A novel series of 1,2,4-triazolyl octahydropyrrolo[2,3-b]pyrroles showing high affinity and selectivity at the DA D3 receptor is reported here. Compounds endowed with high selectivity over the hERG channel were identified and their pharmacokinetic properties thoroughly analyzed. A few derivatives with appropriate developability characteristics were selected for further studies and progression along the screening cascade. In particular, derivative 60a, (DA D3 pKi=8.4, DA D2 pKi=6.0 and hERG fpKi=5.2) showed a balanced profile and further refinements are in progress around this molecule.


Assuntos
Pirróis/farmacologia , Receptores de Dopamina D3/antagonistas & inibidores , Triazóis/farmacologia , Animais , Ligação Competitiva/efeitos dos fármacos , Células CHO , Cricetulus , Relação Dose-Resposta a Droga , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Células HEK293 , Humanos , Modelos Moleculares , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química
20.
Anal Bioanal Chem ; 407(3): 931-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25277104

RESUMO

Home-made micro-solid-phase extraction (SPE) cartridges using different adsorbent materials were tested for the desorption electrospray ionization-high-resolution mass spectrometry (DESI-HRMS) determination of explosives like 2,4,6-trinitrotoluene, cyclotrimethylene-trinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, and trinitrophenylmethylnitramine in soil samples. Quantitation limits in the low nanogram per kilogram range proved the reliability of the method for the detection of explosives at ultra-trace levels. The reduced sample preparation allowed for low costs and high-throughput analyses. Finally, the superior extraction capability of the method was proved by obtaining DESI-HRMS responses at least five times higher than those achieved by performing DESI-HRMS analyses of solid-liquid extracts spotted onto commercial polytetrafluoroethylene slides.


Assuntos
Substâncias Explosivas/análise , Poluentes do Solo/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Azocinas/análise , Desenho de Equipamento , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Tetranitrato de Pentaeritritol/análise , Reprodutibilidade dos Testes , Extração em Fase Sólida/instrumentação , Triazinas/análise , Trinitrotolueno/análise
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