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1.
J Nat Prod ; 87(6): 1628-1634, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38869194

RESUMO

The unfolded protein response (UPR) is a key component of fungal virulence. The prenylated xanthone γ-mangostin isolated from Garcinia mangostana (Clusiaceae) fruit pericarp, has recently been described to inhibit this fungal adaptative pathway. Considering that Calophyllum caledonicum (Calophyllaceae) is known for its high prenylated xanthone content, its stem bark extract was fractionated using a bioassay-guided procedure based on the cell-based anti-UPR assay. Four previously undescribed xanthone derivatives were isolated, caledonixanthones N-Q (3, 4, 8, and 12), among which compounds 3 and 8 showed promising anti-UPR activities with IC50 values of 11.7 ± 0.9 and 7.9 ± 0.3 µM, respectively.


Assuntos
Calophyllum , Resposta a Proteínas não Dobradas , Xantonas , Xantonas/farmacologia , Xantonas/química , Xantonas/isolamento & purificação , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Calophyllum/química , Estrutura Molecular , Humanos , Casca de Planta/química
2.
J Agric Food Chem ; 71(37): 13706-13716, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37697453

RESUMO

Discovering new solutions for crop protection is a major challenge for the next decades as a result of the ecotoxicological impact of classical fungicides, the emergence of fungicide resistances, and the consequence of climate change on pathogen distribution. Previous work on fungal mutants deficient in the unfolded protein response (UPR) supported that targeting this pathway is a promising plant disease control strategy. In particular, we showed that the UPR is involved in fungal virulence by altering cell protection against host defense compounds, such as phytoalexins and phytoanticipins. In this study, we evaluated natural products targeting fungal IRE1 protein (UPR effector) and consequently increasing fungal susceptibility to plant defenses. Developing an in vitro cell-based screening assay allowed for the identification of seven potential IRE1 inhibitors with a focus on polyhydroxylated prenylated xanthones. Inhibition of hac1 mRNA splicing, which is mediated by IRE1, was then validated for the most active compound, namely, γ-mangostin 3. To study the mode of interaction between the binding site of IRE1 and active xanthones, molecular docking was also undertaken, revealing similar and novel interactions between the known inhibitor and the binding site. Eventually, active xanthones applied at subtoxic doses induced a significant reduction in necrosis size for leaves of Brassica oleracea inoculated with Alternaria brassicicola and Botrytis cinerea.


Assuntos
Produtos Biológicos , Fungicidas Industriais , Proteção de Cultivos , Simulação de Acoplamento Molecular , Sítios de Ligação , Proteínas Fúngicas/genética , Fungicidas Industriais/farmacologia , Proteínas Serina-Treonina Quinases
3.
Phytochem Anal ; 34(4): 461-475, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37051779

RESUMO

INTRODUCTION: Propolis is a resinous natural substance collected by honeybees from buds and exudates of various trees and plants; it is widely accepted that the composition of propolis depends on the phytogeographic characteristics of the site of collection. OBJECTIVES: The aim of this study was to determine the phytochemical composition of ethanolic extracts from eight propolis batches collected in different regions of Benin (north, center, and south) and Congo, Africa. MATERIAL AND METHODS: Characterization of propolis samples was performed by using different hyphenated chromatographic methods combined with carbon-13 nuclear magnetic resonance (13 C NMR) dereplication with MixONat software. Their antioxidant or anti-advanced glycation end-product (anti-AGE) activity was then evaluated by using diphenylpicrylhydrazyl and bovine serum albumin assays, respectively. RESULTS: Chromatographic analyses combined with 13 C NMR dereplication showed that two samples from the center of Benin exhibited, in addition to a huge amount of pentacyclic triterpenes, methoxylated stilbenoids or phenanthrenoids, responsible for the antioxidant activity of the extract for the first one. Among them, combretastatins might be cytotoxic. For the second one, the prenylated flavanones known in Macaranga-type propolis were responsible for its significant anti-AGE activity. The sample from Congo was composed of many triterpene derivatives belonging to Mangifera indica species. CONCLUSION: Therefore, propolis from the center of Benin seems to be of particular interest, due to its antioxidant and anti-AGE properties. Nevertheless, as standardization of propolis is difficult in tropical zones due to its great chemodiversity, a systematic phytochemical analysis is required before promoting the use of propolis in food and health products in Africa.


Assuntos
Própole , Animais , Própole/química , Antioxidantes/química , Congo , Benin , Espectroscopia de Ressonância Magnética , Compostos Fitoquímicos
4.
Addict Behav ; 143: 107673, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36893515

RESUMO

This study is a formative assessment of REAL Parenting (RP): a brief, digital intervention for parents of high school students that encourages parent-teen communication about alcohol and, in turn, aims to prevent teen alcohol use. The aims of this study were to describe engagement with, and acceptability and usability of RP; and to explore the relationship of these measures with each other and with short-term outcomes. Participants were 160 parents randomly assigned to the treatment group who received RP as part of a randomized pilot trial (Mage = 45.43[SD = 7.26], 59.3% female, 56% White, 19% Hispanic). App-based program analytics captured real-time engagement with RP. Parents completed self-report measures of acceptability, usability, perceived communication effectiveness, perceived self-efficacy to communicate, and frequency of communication post-intervention. Descriptive statistics were calculated to describe engagement, acceptability and usability, and zero-order correlations were calculated to examine associations between these and self-report variables. About 75% (n = 118) of parents accessed the intervention and two-thirds (n = 110) accessed at least one module. Self-report ratings of acceptability and usability were neutral to positive, and mothers liked RP more than fathers. Self-report, but not program analytic indicators were associated with short-term outcomes. Findings suggest that, with little incentive, most parents will access an app focused on parent-teen communication about alcohol. While parent feedback was positive, it also highlighted areas for improvement with app content and design. Correlations suggest that analytic metrics of engagement are useful to discern who is and is not using interventions, and self-report measures are important for understanding pathways by which interventions are associated with short-term outcomes.


Assuntos
Consumo de Bebidas Alcoólicas , Poder Familiar , Adolescente , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Consumo de Bebidas Alcoólicas/prevenção & controle , Estudantes , Autorrelato , Comunicação
5.
JMIR Res Protoc ; 12: e43986, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36716301

RESUMO

BACKGROUND: Underage drinking and related risky sexual behavior (RSB) are major public health concerns on United States college campuses. Although technology-delivered personalized feedback interventions (PFIs) are considered a best practice for individual-level campus alcohol prevention, there is room for improving the effectiveness of this approach with regard to alcohol-related RSB. OBJECTIVE: The aims of this study are to (1) evaluate the impact of a brief PFI that integrates content on alcohol use and RSB and is adapted to include a novel cross-tailored dynamic feedback (CDF) component for at-risk first-year college students and (2) identify implementation factors critical to the CDF's success to facilitate future scale-up in campus settings. METHODS: This study uses a hybrid type 1 effectiveness-implementation design and will be conducted in 3 phases. Phase 1 is a stakeholder-engaged PFI+CDF adaptation guided by focus groups and usability testing. In phase 2, 600 first-year college students who drink and are sexually active will be recruited from 2 sites (n=300 per site) to participate in a 4-group randomized controlled trial to examine the effectiveness of PFI+CDF in reducing alcohol-related RSB. Eligible participants will complete a baseline survey during the first week of the semester and follow-up surveys at 1, 2, 3, 6, and 13 months post baseline. Phase 3 is a qualitative evaluation with stakeholders to better understand relevant implementation factors. RESULTS: Recruitment and enrollment for phase 1 began in January 2022. Recruitment for phases 2 and 3 is planned for the summer of 2023 and 2024, respectively. Upon collection of data, the effectiveness of PFI+CDF will be examined, and factors critical to implementation will be evaluated. CONCLUSIONS: This hybrid type 1 trial is designed to impact the field by testing an innovative adaptation that extends evidence-based alcohol programs to reduce alcohol-related RSB and provides insights related to implementation to bridge the gap between research and practice at the university level. TRIAL REGISTRATION: ClinicalTrials.gov NCT05011903; https://clinicaltrials.gov/ct2/show/NCT05011903. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/43986.

6.
Bioorg Med Chem ; 75: 117072, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36356534

RESUMO

While many studies have established the importance of protein homeostasis in tumor progression, little effort has been made to examine the therapeutic potential of targeting the HSP60 chaperonin system. In healthy cells, HSP60 is localized to the mitochondrial matrix; however, emerging evidence indicates HSP60 can be over-expressed and mis-localized to the cytosol of cancer cells, which is hypothesized to promote tumor cell survival and proliferation. This opens a potential avenue to selectively target the aberrant HSP60 in the cytosol as a chemotherapeutic strategy. In the present work, we examined a series of bis-aryl-α,ß-unsaturated ketone (ABK) HSP60 inhibitors for their ability to selectively target cancerous vs non-cancerous colon and intestine cells. We found that lead analogs inhibited migration and clonogenicity of cancer cells, with cytotoxicity correlating with the level of aberrant HSP60 in the cytosol.

7.
Molecules ; 27(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35807390

RESUMO

Voltage-gated Na+ (NaV) channels are significant therapeutic targets for the treatment of cardiac and neurological disorders, thus promoting the search for novel NaV channel ligands. With the objective of discovering new blockers of NaV channel ligands, we screened an In-House vegetal alkaloid library using fluorescence cell-based assays. We screened 62 isoquinoline alkaloids (IA) for their ability to decrease the FRET signal of voltage sensor probes (VSP), which were induced by the activation of NaV channels with batrachotoxin (BTX) in GH3b6 cells. This led to the selection of five IA: liriodenine, oxostephanine, thalmiculine, protopine, and bebeerine, inhibiting the BTX-induced VSP signal with micromolar IC50. These five alkaloids were then assayed using the Na+ fluorescent probe ANG-2 and the patch-clamp technique. Only oxostephanine and liriodenine were able to inhibit the BTX-induced ANG-2 signal in HEK293-hNaV1.3 cells. Indeed, liriodenine and oxostephanine decreased the effects of BTX on Na+ currents elicited by the hNaV1.3 channel, suggesting that conformation change induced by BTX binding could induce a bias in fluorescent assays. However, among the five IA selected in the VSP assay, only bebeerine exhibited strong inhibitory effects against Na+ currents elicited by the hNav1.2 and hNav1.6 channels, with IC50 values below 10 µM. So far, bebeerine is the first BBIQ to have been reported to block NaV channels, with promising therapeutical applications.


Assuntos
Alcaloides , Corantes Fluorescentes , Alcaloides/farmacologia , Batraquiotoxinas/metabolismo , Batraquiotoxinas/farmacologia , Viés , Células HEK293 , Humanos , Isoquinolinas/farmacologia , Ligantes , Sódio/metabolismo
8.
FASEB J ; 36(3): e22198, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35199390

RESUMO

GroES/GroEL is the only bacterial chaperone essential under all conditions, making it a potential antibiotic target. Rationally targeting ESKAPE GroES/GroEL as an antibiotic strategy necessitates studying their structure and function. Herein, we outline the structural similarities between Escherichia coli and ESKAPE GroES/GroEL and identify significant differences in intra- and inter-ring cooperativity, required in the refolding cycle of client polypeptides. Previously, we observed that one-half of ESKAPE GroES/GroEL family members could not support cell viability when each was individually expressed in GroES/GroEL-deficient E. coli cells. Cell viability was found to be dependent on the allosteric compatibility between ESKAPE and E. coli subunits within mixed (E. coli and ESKAPE) tetradecameric GroEL complexes. Interestingly, differences in allostery did not necessarily result in differences in refolding rate for a given homotetradecameric chaperonin. Characterization of ESKAPE GroEL allostery, ATPase, and refolding rates in this study will serve to inform future studies focused on inhibitor design and mechanism of action studies.


Assuntos
Sítio Alostérico , Proteínas de Escherichia coli/química , Proteínas de Choque Térmico/química , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Regulação Alostérica , Chaperonina 10/química , Chaperonina 10/genética , Chaperonina 10/metabolismo , Escherichia coli , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo
9.
Plants (Basel) ; 11(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35050032

RESUMO

Concentrated bud macerates (CBMs) are obtained from meristematic tissues such as buds and young shoots by maceration in a solvent composed of glycerin, water and ethanol (1/1/1/, v/v). Their traditional utilization in gemmotherapy has gained interest in the past years, and the knowledge of their chemical characterization can provide commercial arguments, particularly to secure their quality control. Therefore, an optimized method for phytochemical analysis including glycerol removal by a preliminary solid phase extraction (SPE) followed by compound identification using high performance liquid chromatography coupled with ultra-violet and tandem mass detectors (HPLC-UV-MS2) was developed. This method was applied on 5 CBMs obtained from Alnus glutinosa, Ribesnigrum, Rosmarinus officinalis, Rosa canina and Tilia tomentosa in order to determinate their chemical composition. Their antioxidant effects were also investigated by radical scavenging activity assays (DPPH and ORAC). Glycerol removal improved the resolution of HPLC chemical profiles and allowed us to perform TLC antioxidant screening. Our approach permitted the identification of 57 compounds distributed in eight major classes, three of them being common to all macerates including nucleosides, phenolic acids and glycosylated flavonoids. Quantification of the later class as a rutin equivalent (RE) showed a great disparity between Rosa canina macerate (809 mg RE/L), and the other ones (from 175 to 470 mg RE/L). DPPH and ORAC assays confirmed the great activity of Rosa canina (4857 and 6479 µmol TE/g of dry matter, respectively). Finally, phytochemical and antioxidant analysis of CBMs strengthened their phytomedicinal interest in the gemmotherapy field.

10.
J Health Psychol ; 27(4): 923-935, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33353412

RESUMO

Frequent indoor tanning bed use is an established public health concern, yet research on tanning cessation interventions for frequent tanners is lacking. We describe the protocol for a brief, web-based tanning behavior change intervention and present evidence that it is acceptable and engaging to frequent indoor tanners. Lower tanning rates were not observed among participants receiving the intervention in a randomized controlled trial but participants' interest in changing tanning increased. This intervention could be a useful approach to increasing frequent tanners' interest in behavior change and openness to engaging within a more intensive, multi-component tanning cessation program.Trial Registration: NCT03448224 Clinical Trials.gov (https://clinicaltrials.gov/ct2/show/NCT03448224?cond=NCT03448224&draw=2&rank=1).


Assuntos
Banho de Sol , Retroalimentação , Comportamentos Relacionados com a Saúde , Humanos , Internet
11.
J Am Coll Health ; 70(5): 1493-1499, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-32870746

RESUMO

Objective: To examine race, gender, and alcohol use level as moderators of the association between protective behavioral strategies (PBS) and alcohol-related problems. Participants: A sample of 12,011 participants who reported recent drinking (87.7% White, 61% Women) from Project INTEGRATE, a study that combined individual participant data (IPD) from 24 brief motivational intervention trials for college students. Methods: Hierarchical regressions were conducted to determine whether there was a moderated effect of PBS on alcohol problems across alcohol use levels, and whether the moderated protective effect of PBS by alcohol use differed by gender and race. Results: The protective association between PBS and alcohol-related problems was greater for those who drank less. This moderated effect did not differ across men and women or across racial groups. Conclusions: College drinking prevention programs should ensure that students are aware of the limits of PBS as a mitigator of alcohol problems.


Assuntos
Consumo de Álcool na Faculdade , Transtornos Relacionados ao Uso de Álcool , Consumo de Bebidas Alcoólicas/prevenção & controle , Feminino , Humanos , Masculino , Estudantes , Universidades
12.
Toxicon ; 201: 141-147, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34474068

RESUMO

Liriodenine is a biologically active plant alkaloid with multiple effects on mammals, fungi, and bacteria, but has never been evaluated for insecticidal activity. Accordingly, liriodenine was applied topically in ethanolic solutions to adult female Anopheles gambiae, and found to be mildly toxic. Its lethality was synergized in mixtures with dimethyl sulfoxide and piperonyl butoxide. Recordings from the ventral nerve cord of larval Drosophila melanogaster showed that liriodenine was neuroexcitatory and reversed the inhibitory effect of 1 mM GABA at effective concentrations of 20-30 µM. GABA antagonism on the larval nervous system was equally expressed on both susceptible and cyclodiene-resistant rdl preparations. Acutely isolated neurons from Periplaneta americana were studied under patch clamp and inhibition of GABA-induced currents with an IC50 value of about 1 µM were observed. In contrast, bicuculline did not reverse the effects of GABA on cockroach neurons, as expected. In silico molecular models suggested reasonable structural concordance of liriodenine and bicuculline and isosteric hydrogen bond acceptor sites. This study is the first assessing of the toxicology of liriodenine on insects and implicates the GABA receptor as one likely neuronal target, where liriodenine might be considered an active chemical analog of bicuculline.


Assuntos
Aporfinas , Inseticidas , Animais , Aporfinas/toxicidade , Drosophila melanogaster , Feminino , Inseticidas/toxicidade , Receptores de GABA
13.
Phytochem Anal ; 32(6): 1102-1109, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33938065

RESUMO

INTRODUCTION: Xanthones are metabolites with a variety of biological properties. The Clusiaceae family, which until recently included the genus Calophyllum, is recognised for its production of monohydroxylated and polyhydroxylated xanthones. Presently, C. brasiliense is the only Calophyllum spp. known to occur in the Yucatan peninsula. OBJECTIVE: To use a combination of traditional phytochemical methods and carbon-13 nuclear magnetic resonance (13 C-NMR) dereplication analysis to identify xanthones in the stem bark of C. brasiliense. MATERIAL AND METHODS: Initial fractionation and purification of the stem bark extract of C. brasiliense produced macluraxanthone (1). Additional xanthones, together with chromanones and terpenoids, were identified using 13 C-NMR dereplication analysis in different semipurified fractions obtained from the low and medium polarity fractions of the stem bark extract of C. brasiliense. RESULTS: Initial identification of macluraxanthone (1) was confirmed by 13 C-NMR dereplication analysis; additionally, 13 C-NMR dereplication analysis allowed the identification of a number of monohydroxylated and polyhydroxylated xanthones, together with chromanones and terpenoids. CONCLUSION: This study confirms C. brasiliense as a rich source of xanthones and the 13 C-NMR dereplication analysis as a suitable method to quickly identify the presence of different families of secondary metabolites in semipurified fractions.


Assuntos
Calophyllum , Xantonas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Casca de Planta , Extratos Vegetais
14.
Bioorg Med Chem ; 40: 116129, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33971488

RESUMO

Over the past few decades, an increasing variety of molecular chaperones have been investigated for their role in tumorigenesis and as potential chemotherapeutic targets; however, the 60 kDa Heat Shock Protein (HSP60), along with its HSP10 co-chaperone, have received little attention in this regard. In the present study, we investigated two series of our previously developed inhibitors of the bacterial homolog of HSP60/10, called GroEL/ES, for their selective cytotoxicity to cancerous over non-cancerous colorectal cells. We further developed a third "hybrid" series of analogs to identify new candidates with superior properties than the two parent scaffolds. Using a series of well-established HSP60/10 biochemical screens and cell-viability assays, we identified 24 inhibitors (14%) that exhibited > 3-fold selectivity for targeting colorectal cancer over non-cancerous cells. Notably, cell viability EC50 results correlated with the relative expression of HSP60 in the mitochondria, suggesting a potential for this HSP60-targeting chemotherapeutic strategy as emerging evidence indicates that HSP60 is up-regulated in colorectal cancer tumors. Further examination of five lead candidates indicated their ability to inhibit the clonogenicity and migration of colorectal cancer cells. These promising results are the most thorough analysis and first reported instance of HSP60/10 inhibitors being able to selectively target colorectal cancer cells and highlight the potential of the HSP60/10 chaperonin system as a viable chemotherapeutic target.


Assuntos
Antineoplásicos/farmacologia , Benzoxazóis/farmacologia , Chaperonina 10/antagonistas & inibidores , Chaperonina 60/antagonistas & inibidores , Neoplasias Colorretais/tratamento farmacológico , Salicilanilidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Benzoxazóis/síntese química , Benzoxazóis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chaperonina 10/metabolismo , Chaperonina 60/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Salicilanilidas/síntese química , Salicilanilidas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
mBio ; 12(1)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436430

RESUMO

As the GroES/GroEL chaperonin system is the only bacterial chaperone that is essential under all conditions, we have been interested in the development of GroES/GroEL inhibitors as potential antibiotics. Using Escherichia coli GroES/GroEL as a surrogate, we have discovered several classes of GroES/GroEL inhibitors that show potent antibacterial activity against both Gram-positive and Gram-negative bacteria. However, it remains unknown if E. coli GroES/GroEL is functionally identical to other GroES/GroEL chaperonins and hence if our inhibitors will function against other chaperonins. Herein we report our initial efforts to characterize the GroES/GroEL chaperonins from clinically significant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). We used complementation experiments in GroES/GroEL-deficient and -null E. coli strains to report on exogenous ESKAPE chaperone function. In GroES/GroEL-deficient (but not knocked-out) E. coli, we found that only a subset of the ESKAPE GroES/GroEL chaperone systems could complement to produce a viable organism. Surprisingly, GroES/GroEL chaperone systems from two of the ESKAPE pathogens were found to complement in E. coli, but only in the strict absence of either E. coli GroEL (P. aeruginosa) or both E. coli GroES and GroEL (E. faecium). In addition, GroES/GroEL from S. aureus was unable to complement E. coli GroES/GroEL under all conditions. The resulting viable strains, in which E. coligroESL was replaced with ESKAPE groESL, demonstrated similar growth kinetics to wild-type E. coli, but displayed an elongated phenotype (potentially indicating compromised GroEL function) at some temperatures. These results suggest functional differences between GroES/GroEL chaperonins despite high conservation of amino acid identity.IMPORTANCE The GroES/GroEL chaperonin from E. coli has long served as the model system for other chaperonins. This assumption seemed valid because of the high conservation between the chaperonins. It was, therefore, shocking to discover ESKAPE pathogen GroES/GroEL formed mixed-complex chaperonins in the presence of E. coli GroES/GroEL, leading to loss of organism viability in some cases. Complete replacement of E. coligroESL with ESKAPE groESL restored organism viability, but produced an elongated phenotype, suggesting differences in chaperonin function, including client specificity and/or refolding cycle rates. These data offer important mechanistic insight into these remarkable machines, and the new strains developed allow for the synthesis of homogeneous chaperonins for biochemical studies and to further our efforts to develop chaperonin-targeted antibiotics.


Assuntos
Chaperonina 10/genética , Chaperonina 60/genética , Escherichia coli/genética , Bactérias Gram-Negativas/genética , Bactérias Gram-Positivas/genética , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Antibacterianos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Chaperonina 10/química , Chaperonina 10/metabolismo , Chaperonina 60/química , Chaperonina 60/metabolismo , Enterobacter/efeitos dos fármacos , Enterobacter/genética , Enterobacter/metabolismo , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Técnicas de Introdução de Genes , Técnicas de Inativação de Genes , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/metabolismo , Cinética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
16.
Prev Sci ; 22(2): 247-258, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33140287

RESUMO

Prevention curricula rely on audience engagement to effectively communicate their messages. However, to date, measurement of engagement has primarily focused on self-report that is often an indicator of liking or satisfaction. Emerging technologies for intervention delivery hold promise not only for additional engagement indicators but also for dissemination outside of traditional vehicles such as classroom delivery. The present study, grounded in the theory of active involvement (Greene 2013), explores the role of engagement (as measured by self-report, program analytics, and observation) with short-term substance use prevention outcomes such as self-efficacy to counter-argue and descriptive and injunctive norms. The study tracks 4-H youth (N = 310) engaged with a media literacy focused e-learning substance prevention curriculum, REAL media. Results indicate that self-reports of engagement predicted self-efficacy to counter-argue, but a program-analytic indicator of dosage predicted lower injunctive and descriptive norms, all at 3 months. The observational indicator was correlated with self-efficacy to counter-argue but not significant in the predictive models. The implications and directions for future research regarding how engagement is measured in prevention and included in studying program effects are discussed. Clinical trial: NCT03157700, May 2017.


Assuntos
Alfabetização Digital , Currículo , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Humanos , Autoeficácia , Autorrelato , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle
17.
Bioorg Med Chem ; 28(22): 115710, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007545

RESUMO

In two previous studies, we identified compound 1 as a moderate GroEL/ES inhibitor with weak to moderate antibacterial activity against Gram-positive and Gram-negative bacteria including Bacillus subtilis, methicillin-resistant Staphylococcus aureus, Klebsiella pneumonia, Acinetobacter baumannii, and SM101 Escherichia coli (which has a compromised lipopolysaccharide biosynthetic pathway making bacteria more permeable to drugs). Extending from those studies, we developed two series of analogs with key substructures resembling those of known antibacterials, nitroxoline (hydroxyquinoline moiety) and nifuroxazide/nitrofurantoin (bis-cyclic-N-acylhydrazone scaffolds). Through biochemical and cell-based assays, we identified potent GroEL/ES inhibitors that selectively blocked E. faecium, S. aureus, and E. coli proliferation with low cytotoxicity to human colon and intestine cells in vitro. Initially, only the hydroxyquinoline-bearing analogs were found to be potent inhibitors in our GroEL/ES-mediated substrate refolding assays; however, subsequent testing in the presence of an E. coli nitroreductase (NfsB) in situ indicated that metabolites of the nitrofuran-bearing analogs were potent GroEL/ES inhibitor pro-drugs. Consequently, this study has identified a new target of nitrofuran-containing drugs, and is the first reported instance of such a unique class of GroEL/ES chaperonin inhibitors. The intriguing results presented herein provide impetus for expanded studies to validate inhibitor mechanisms and optimize this antibacterial class using the respective GroEL/ES chaperonin systems and nitroreductases from E. coli and the ESKAPE bacteria.


Assuntos
Antibacterianos/farmacologia , Chaperonina 60/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Nitrofuranos/farmacologia , Pró-Fármacos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Chaperonina 60/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nitrofuranos/síntese química , Nitrofuranos/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Relação Estrutura-Atividade
18.
Drug Alcohol Depend ; 214: 108170, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32693198

RESUMO

BACKGROUND: The primary aim of this study was to evaluate the short-term effects of testing an e-learning program to reduce adolescent substance use and abuse. Early initiation of substance use is linked to a variety of negative outcomes, thus effective intervention programs are needed. One approach is to use media literacy to capitalize on adolescents' immersion with media in a variety of forms. We developed, implemented, and tested an engaging substance use prevention program by collaborating with a youth-oriented community partner (4-H). METHODS: 639 middle adolescents from nine U.S. states participated in an RCT of REAL media. Participants completed a series of online surveys and were randomized to use an online substance prevention program (REAL media) or serve as control (delayed program use). Self-report surveys were administered at three points in time. This short-term evaluation uses data from the pretest (Time 1) and short-term posttest three-month surveys, which measured demographics, self-efficacy to counterargue, and injunctive and descriptive substance use norms. RESULTS: Participants who completed the REAL media program reported increased self-efficacy to counterargue and decreased positive injunctive norms compared to control participants who did not complete the program. No significant differences were observed for descriptive norms. CONCLUSIONS: We found support for the REAL media program in changing key predictors of youth substance use demonstrating (1) the efficacy of media literacy interventions targeting adolescents and (2) that e-learning substance use prevention efforts can be adapted for and implemented through community organizations.


Assuntos
Instrução por Computador , Promoção da Saúde , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Adolescente , Comportamento do Adolescente , Currículo , Feminino , Humanos , Alfabetização , Masculino , Autoeficácia , Inquéritos e Questionários
19.
Anal Chem ; 92(13): 8793-8801, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32479074

RESUMO

Whether chemists or biologists, researchers dealing with metabolomics require tools to decipher complex mixtures. As a part of metabolomics and initially dedicated to identifying bioactive natural products, dereplication aims at reducing the usual time-consuming process of known compounds isolation. Mass spectrometry and nuclear magnetic resonance are the most commonly reported analytical tools during dereplication analysis. Though it has low sensitivity, 13C NMR has many advantages for such a study. Notably, it is nonspecific allowing simultaneous high-resolution analysis of any organic compounds including stereoisomers. Since NMR spectrometers nowadays provide useful data sets in a reasonable time frame, we have embarked upon writing software dedicated to 13C NMR dereplication. The present study describes the development of a freely distributed algorithm, namely MixONat and its ability to help researchers decipher complex mixtures. Based on Python 3.5, MixONat analyses a {1H}-13C NMR spectrum optionally combined with DEPT-135 and 90 data-to distinguish carbon types (i.e., CH3, CH2, CH, and C)-as well as a MW filtering. The software requires predicted or experimental carbon chemical shifts (δc) databases and displays results that can be refined based on user interactions. As a proof of concept, this 13C NMR dereplication strategy was evaluated on mixtures of increasing complexity and exhibiting pharmaceutical (poppy alkaloids), nutritional (rosemary extracts) or cosmetics (mangosteen peel extract) applications. Associated results were compared with other methods commonly used for dereplication. MixONat gave coherent results that rapidly oriented the user toward the correct structural types of secondary metabolites, allowing the user to distinguish between structurally close natural products, including stereoisomers.


Assuntos
Produtos Biológicos/química , Espectroscopia de Ressonância Magnética/métodos , Software , Algoritmos , Alcaloides/química , Isótopos de Carbono/química , Bases de Dados de Compostos Químicos , Garcinia mangostana/química , Garcinia mangostana/metabolismo , Papaver/química , Papaver/metabolismo , Extratos Vegetais/química , Rosmarinus/química , Rosmarinus/metabolismo
20.
Clin J Sport Med ; 30(3): 203-209, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32341286

RESUMO

OBJECTIVE: Accurate diagnosis of sport-related concussions relies heavily on truthful self-reporting of symptom severity. Previous studies have emphasized lack of knowledge as a factor in symptom nondisclosure. This study sought to examine concussion knowledge and the relationship of knowledge to reasons for symptom nondisclosure. DESIGN: Cross-sectional study. SETTING: Data were collected during preparticipation athletic evaluations via electronic survey. PARTICIPANTS: One hundred fifty-six incoming National Collegiate Athletic Association Division I student-athletes. MAIN OUTCOME MEASURES: Survey items included previous concussion diagnosis, concussion fact and symptom knowledge, reasons and situational contexts for nondisclosure, and stakeholder attitudes. RESULTS: Participants, on average, had substantial concussion symptom and fact knowledge. Unexpectedly, participants with higher concussion fact knowledge endorsed more reasons that athletes may hide symptoms. Concussion symptom knowledge was unrelated to reasons for nondisclosure. Athletes believed that symptom reporting was less likely in high-stakes versus low-stakes situations and consistently identified their teammates as holding attitudes that support underreporting and athletic trainers as engaging in behaviors that support player safety. CONCLUSIONS: Greater concussion knowledge did not reduce the number of reasons that participants viewed as drivers for concussion nondisclosure. In other words, participants understood why athletes choose to hide symptoms even when they also understood the symptoms, risks, sequelae, and consequences of concussion (and potential harm of nondisclosure). Situational contexts and important stakeholder attitudes also appeared to importantly influence symptom disclosure decisions. A multifaceted approach that goes beyond current educational strategies to addresses situational, social, and athletic pressures may be needed to initiate a widespread cultural shift away from concussion nondisclosure.


Assuntos
Atletas/psicologia , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Revelação/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Autorrelato , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Motivação , Participação dos Interessados , Inquéritos e Questionários
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