Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Exp Aging Res ; : 1-22, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278144

RESUMO

This study examined the effectiveness of a multiple group membership intervention for reducing the negative effects of age-based stereotype threat (ABST) on older adults' objective memory performance and subjective memory concerns. Healthy older adults (N = 68) were randomly allocated to an ABST + threat-removal (ABST+TR) or ABST + active-control (ABST+AC) condition. After activating ABST, the ABST+TR condition completed a group-listing task and the ABST+AC condition completed a meal-listing task. Participants then completed the Rey Auditory Verbal Learning Test (RAVLT) and Everyday Memory Questionnaire - Revised. One significant difference was found in memory performance between conditions; specifically, after controlling for age, gender, and number of items listed, those in the ABST+TR condition performed significantly better on the RAVLT memory interference trial. Further, listing a greater number of group memberships was associated with better memory performance in the ABST+TR condition. No significant difference was found in subjective memory concerns between the ABST+TR condition and the ABST+AC condition. Overall, the current findings indicated that raising the salience of multiple group memberships offered limited protection for older adults' cognitive test performance in the context of ABST.

2.
Molecules ; 29(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675653

RESUMO

Leishmaniasis, an infectious disease caused by pathogenic Leishmania parasites, affects millions of people in developing countries, and its re-emergence in developed countries, particularly in Europe, poses a growing public health concern. The limitations of current treatments and the absence of effective vaccines necessitate the development of novel therapeutics. In this study, we focused on identifying small molecule inhibitors which prevents the interaction between peroxin 5 (PEX5) and peroxisomal targeting signal 1 (PTS1), pivotal for kinetoplastid parasite survival. The Leishmania donovani PEX5, containing a C-terminal tetratricopeptide repeat (TPR) domain, was expressed and purified, followed by the quantification of kinetic parameters of PEX5-PTS1 interactions. A fluorescence polarization-based high-throughput screening assay was developed and small molecules inhibiting the LdPEX5-PTS1 interaction were discovered through the screening of a library of 51,406 compounds. Based on the confirmatory assay, nine compounds showed half maximal inhibitory concentration (IC50) values ranging from 3.89 to 24.50 µM. In silico docking using a homology model of LdPEX5 elucidated that the molecular interactions between LdPEX5 and the inhibitors share amino acids critical for PTS1 binding. Notably, compound P20 showed potent activity against the growth of L. donovani promastigotes, L. major promastigotes, and Trypanosoma brucei blood stream form, with IC50 values of 12.16, 19.21, and 3.06 µM, respectively. The findings underscore the potential of targeting LdPEX5-PTS1 interactions with small molecule inhibitors as a promising strategy for the discovery of new anti-parasitic compounds.


Assuntos
Ensaios de Triagem em Larga Escala , Leishmania donovani , Simulação de Acoplamento Molecular , Receptor 1 de Sinal de Orientação para Peroxissomos , Proteínas de Protozoários , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Receptor 1 de Sinal de Orientação para Peroxissomos/metabolismo , Receptor 1 de Sinal de Orientação para Peroxissomos/química , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/química , Polarização de Fluorescência/métodos , Ligação Proteica , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Antiprotozoários/farmacologia , Antiprotozoários/química , Humanos
3.
Int J Mol Sci ; 25(1)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38203471

RESUMO

Madurastatins are a group of pentapeptides containing an oxazoline moiety, and, in a few cases, an imidazolidinone ring as an additional structural feature. In our search for new potential antiparasitic metabolites from natural sources, we studied the acetone extracts from a culture of Actinomadura sp. CA-135719. The LC/HRMS analysis of this extract identified the presence of the known madurastatins C1 (1), D1 (4), and D2 (5) together with additional members of the family that were identified as the new madurastatins H2 (2) and 33-epi-D1 (3) after isolation and spectroscopic analysis. The planar structures of the new compounds were established by HRMS, ESI-qTOF-MS/MS, and 1D and 2D NMR data, and their absolute configuration was proposed using Marfey's and bioinformatic analyses of the biosynthetic gene cluster (BGC). A revision of the absolute configuration of madurastatins D1 and D2 is proposed. Additionally, madurastatins containing imidazolidinone rings are proved to be artifacts originating during acetone extraction of the bacterial cultures.


Assuntos
Acetona , Produtos Biológicos , Solventes , Espectrometria de Massas em Tandem , Antiparasitários
4.
Gerontologist ; 64(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38963814

RESUMO

BACKGROUND AND OBJECTIVES: Prosociality refers to voluntary behaviors that intend to benefit others. Most of the existing literature suggests that older adults tend to act more prosocially compared to younger adults, whereas some studies show that older adults might not be that prosocial under certain conditions. The current study aimed to summarize the mixed findings and quantify the age difference in prosociality by conducting a qualitative systematic review and a quantitative meta-analysis. RESEARCH DESIGN AND METHODS: Literature search was conducted based on 5 databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed and this review was registered at PROSPERO (CRD42022333373). RESULTS: Based on the qualitative synthesis of 51 studies, older adults (n = 109,911) were more prosocial than younger adults (n = 68,501). The meta-analysis of 46 studies further supported this age effect (Hedges' g = 0.31, 95% confidence interval [0.24, 0.37]), and this age effect might be moderated by the types of prosociality. We discovered a moderate age effect in sharing (Hedges' g = 0.53), but a nonsignificant age effect in helping (Hedges' g = 0.11), comforting (Hedges' g = -0.20), or mixed prosociality (Hedges' g = 0.15). Additionally, the age effect was only significant when older adults had higher socioeconomic status than younger adults. DISCUSSION AND IMPLICATIONS: Future research should develop more comprehensive measures of prosociality, examine more variables that influence aging and prosociality, and investigate the neural mechanism(s) of prosociality to achieve a thorough understanding of the age difference in prosociality.


Assuntos
Comportamento Social , Humanos , Idoso , Fatores Etários , Adulto , Adulto Jovem , Envelhecimento/psicologia , Altruísmo , Masculino , Feminino
5.
Sci Rep ; 14(1): 115, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168140

RESUMO

Hepatocellular carcinoma (HCC) is a complex disease associated with a plethora of environmental and genetic/hereditary causative risk factors, more so than other oncological indications. Additionally, patients with HCC exhibit fibrosis, cirrhosis, and liver-related disease. This complicated etiology can affect the disease course and likely contributes to its poor prognosis. In this study, we aimed to improve HCC therapy by evaluating combination treatment using anti-cancer and anti-fibrosis drugs via identification of novel anti-fibrosis drugs. We performed high-throughput screening of 10,000 compounds to identify hepatic fibrosis inhibitors through morphometry analysis of multicellular hepatic spheroid (MCHS) models and identified CHIR-99021 as a candidate anti-fibrotic drug. Treatment with CHIR-99021 induced loss of cell-cell interactions and suppression of extracellular matrix-related protein expression via reprogramming of hepatic stellate cell (HSC) activation in MCHSs. In particular, CHIR-99021 regulated DNMT3B expression only in activated HSCs. Moreover, CHIR-99021 markedly improved the efficacy of sorafenib in HCC- multicellular tumor spheroids in vitro and through induction of apoptosis by decreasing DNMT3B expression in vivo. In summary, these findings suggest that targeting HSC reprogramming by attenuation of DNMT3B expression in the tumor environment might represent a promising therapeutic strategy for liver fibrosis and HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Células Estreladas do Fígado/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Microambiente Tumoral , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Cirrose Hepática/induzido quimicamente
6.
Patient Educ Couns ; 118: 108023, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866073

RESUMO

OBJECTIVE: Patient feedback is rarely gathered systematically in cognitive rehabilitation research. This study examined the perceptions and experiences of people with traumatic brain injury (TBI) who participated in a trial of a 6-session educational program for the rehabilitation of prospective memory (PM) impairment. METHODS: A mixed methods design was used with 47 participants with TBI who completed a compensatory strategy training program (COMP) or COMP plus metacognitive strategy training program (COMP-MST) delivered by an occupational therapist. Data were collected via a participant survey, extracts from progress notes, and audiotaped discussions about learnings from the program during the final session. RESULTS: Participants from both programs were highly satisfied and perceived improvements in everyday PM performance post-intervention. Elements that were highly valued include setting individualised client-centred goals, repetitive training of strategy use, establishing habits and routines, and receiving experiential, verbal, and written feedback.Changes including more therapy sessions were recommended. CONCLUSIONS: Both the COMP and COMP-MST programs were perceived as effective by participants with TBI in improving their PM performance in everyday life using compensatory strategies such as assistive technology. PRACTICE IMPLICATIONS: Routine collection of patient feedback on cognitive rehabilitation can provide valuable information to support person-centred implementation of clinical practice guidelines.


Assuntos
Lesões Encefálicas Traumáticas , Memória Episódica , Humanos , Lesões Encefálicas Traumáticas/psicologia , Lesões Encefálicas Traumáticas/reabilitação , Cognição , Aprendizagem , Transtornos da Memória , Resultado do Tratamento , Ensaios Clínicos como Assunto
7.
Adv Sci (Weinh) ; 11(28): e2400858, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38747156

RESUMO

Small molecule can be utilized to restore the effectiveness of existing major classes of antibiotics against antibiotic-resistant bacteria. In this study, it is demonstrated that celastrol, a natural compound, can modify the bacterial cell wall and subsequently render bacteria more suceptible to ß-lactam antibiotics. It is shown that celastrol leads to incomplete cell wall crosslinking by modulating levels of c-di-AMP, a secondary messenger, in methicillin-resistant Staphylococcus aureus (MRSA). This mechanism enables celastrol to act as a potentiator, effectively rendering MRSA susceptible to a range of penicillins and cephalosporins. Restoration of in vivo susceptibility of MRSA to methicillin is also demonstrated using a sepsis animal model by co-administering methicillin along with celastrol at a much lower amount than that of methicillin. The results suggest a novel approach for developing potentiators for major classes of antibiotics by exploring molecules that re-program metabolic pathways to reverse ß-lactam-resistant strains to susceptible strains.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Peptidoglicano , Resistência beta-Lactâmica , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Peptidoglicano/metabolismo , Resistência beta-Lactâmica/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Modelos Animais de Doenças , Testes de Sensibilidade Microbiana , Camundongos , Triterpenos Pentacíclicos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Parede Celular/metabolismo , Parede Celular/efeitos dos fármacos , beta-Lactamas/farmacologia , Triterpenos/farmacologia , Triterpenos/metabolismo
8.
Infect Dis Model ; 9(2): 474-482, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38404914

RESUMO

An AI-empowered indoor digital contact-tracing system was developed using a centralized architecture and advanced low-energy Bluetooth technologies for indoor positioning, with careful preservation of privacy and data security. We analyzed the contact pattern data from two RCHs and investigated a COVID-19 outbreak in one study site. To evaluate the effectiveness of the system in containing outbreaks with minimal contacts under quarantine, a simulation study was conducted to compare the impact of different quarantine strategies on outbreak containment within RCHs. The significant difference in contact hours between weekdays and weekends was observed for some pairs of RCH residents and staff during the two-week data collection period. No significant difference between secondary cases and uninfected contacts was observed in a COVID-19 outbreak in terms of their demographics and contact patterns. Simulation results based on the collected contact data indicated that a threshold of accumulative contact hours one or two days prior to diagnosis of the index case could dramatically increase the efficiency of outbreak containment within RCHs by targeted isolation of the close contacts. This study demonstrated the feasibility and efficiency of employing an AI-empowered system in indoor digital contact tracing of outbreaks in RCHs in the post-pandemic era.

9.
EBioMedicine ; 102: 105073, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520916

RESUMO

BACKGROUND: The current pipeline for new antibiotics fails to fully address the significant threat posed by drug-resistant Gram-negative bacteria that have been identified by the World Health Organization (WHO) as a global health priority. New antibacterials acting through novel mechanisms of action are urgently needed. We aimed to identify new chemical entities (NCEs) with activity against Klebsiella pneumoniae and Acinetobacter baumannii that could be developed into a new treatment for drug-resistant infections. METHODS: We developed a high-throughput phenotypic screen and selection cascade for generation of hit compounds active against multidrug-resistant (MDR) strains of K. pneumoniae and A. baumannii. We screened compound libraries selected from the proprietary collections of three pharmaceutical companies that had exited antibacterial drug discovery but continued to accumulate new compounds to their collection. Compounds from two out of three libraries were selected using "eNTRy rules" criteria associated with increased likelihood of intracellular accumulation in Escherichia coli. FINDINGS: We identified 72 compounds with confirmed activity against K. pneumoniae and/or drug-resistant A. baumannii. Two new chemical series with activity against XDR A. baumannii were identified meeting our criteria of potency (EC50 ≤50 µM) and absence of cytotoxicity (HepG2 CC50 ≥100 µM and red blood cell lysis HC50 ≥100 µM). The activity of close analogues of the two chemical series was also determined against A. baumannii clinical isolates. INTERPRETATION: This work provides proof of principle for the screening strategy developed to identify NCEs with antibacterial activity against multidrug-resistant critical priority pathogens such as K. pneumoniae and A. baumannii. The screening and hit selection cascade established here provide an excellent foundation for further screening of new compound libraries to identify high quality starting points for new antibacterial lead generation projects. FUNDING: BMBF and GARDP.


Assuntos
Ensaios de Triagem em Larga Escala , Bibliotecas de Moléculas Pequenas , Humanos , Bibliotecas de Moléculas Pequenas/farmacologia , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Escherichia coli , Farmacorresistência Bacteriana Múltipla
10.
Genes (Basel) ; 15(1)2023 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-38254919

RESUMO

Neuropeptides are mostly expressed in regions of the brain responsible for learning and memory and are centrally involved in cognitive pathways. The majority of neuropeptide research has been performed in animal models; with acknowledged differences between species, more research into the role of neuropeptides in humans is necessary to understand their contribution to higher cognitive function. In this study, we investigated the influence of genetic polymorphisms in neuropeptide genes on verbal learning and memory. Variants in genes encoding neuropeptides and neuropeptide receptors were tested for association with learning and memory measures using the Hopkins Verbal Learning Test-Revised (HVLT-R) in a healthy cohort of individuals (n = 597). The HVLT-R is a widely used task for verbal learning and memory assessment and provides five sub-scores: recall, delay, learning, retention, and discrimination. To determine the effect of candidate variants on learning and memory performance, genetic association analyses were performed for each HVLT-R sub-score with over 1300 genetic variants from 124 neuropeptide and neuropeptide receptor genes, genotyped on Illumina OmniExpress BeadChip arrays. This targeted analysis revealed numerous suggestive associations between HVLT-R test scores and neuropeptide and neuropeptide receptor gene variants; candidates include the SCG5, IGFR1, GALR1, OXTR, CCK, and VIPR1 genes. Further characterization of these genes and their variants will improve our understanding of the genetic contribution to learning and memory and provide insight into the importance of the neuropeptide network in humans.


Assuntos
Neuropeptídeos , Aprendizagem Verbal , Animais , Humanos , Aprendizagem , Neuropeptídeos/genética , Polimorfismo Genético , Receptores de Neuropeptídeos/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA