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1.
Angew Chem Int Ed Engl ; : e202401782, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818649

RESUMO

gem-Diborylalkanes are highly valuable building blocks in organic synthesis and the pharmaceutical chemistry due to their ability to participate in multi-step cross-coupling transformations, allowing for the rapid generation of molecular complexity. While progress has been made in their synthetic metholodology, the construction of ß-tertiary and C(sp3)-rich gem-diborylalkanes remains a synthetic challenge due to substrate limitations and steric hindrance issues. An approach is presented that utilizes synergistic photoredox and copper catalysis to achieve efficient C(sp3)-C(sp3) cross-coupling of alkyl N-hydroxyphthalimide esters, which can be easily obtained from alkyl carboxylic acids, with diborylmethyl species, providing a series of C(sp3)-rich gem-diborylalkanes with 1°, 2°, and even 3° ß positions. Furthermore, this approach can also be applied to complex medicinal compounds and natural products, offering rapid access to molecular complexity and late-stage functionalization of C(sp3)-rich drug candidates. Mechanistic experiments revealed that diborylmethyl Cu(I) species participated in both the photoredox process and the key C(sp3)-C(sp3) bond-forming step.

2.
Crit Rev Food Sci Nutr ; : 1-14, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36876514

RESUMO

Lipopeptides, a class of compounds consisting of a peptide ring and a fatty acid chain, are secondary metabolites produced by Bacillus spp. As their hydrophilic and oleophilic properties, lipopeptides are widely used in food, medicine, environment and other industrial or agricultural fields. Compared with artificial synthetic surfactants, microbial lipopeptides have the advantages of low toxicity, high efficiency and versatility, resulting in urgent market demand and broad development prospect of lipopeptides. However, due to the complex metabolic network and precursor requirements of synthesis, the specific and strict synthesis pathway, and the coexistence of multiple homologous substances, the production of lipopeptides by microorganisms has the problems of high cost and low production efficiency, limiting the mass production of lipopeptides and large-scale application in industry. This review summarizes the types of Bacillus-produced lipopeptides and their biosynthetic pathways, introduces the versatility of lipopeptides, and describes the methods to improve the production of lipopeptides, including genetic engineering and optimization of fermentation conditions.

3.
J Prosthodont ; 32(5): 111-117, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35848886

RESUMO

PURPOSE: To compare the accuracies of three intraoral scanners for shade determination function in vitro, and to preliminarily investigate the shade-matching characteristics of the three intraoral scanners. MATERIALS AND METHODS: The shade of the middle third region of each shade tab on the Vita Classical A1-D4 shade guide (VC) was measured with a spectrophotometer (Vita Easyshade V, VE) and three intraoral scanners, including CEREC Omnicam (OM), 3Shape TRIOS 3 (T3), and TRIOS 4 (T4). A conversion table between VC values and CIELAB values was established from the database of VE to analyze the trueness. The reproducibility of the instruments was then compared by repeating the measurements five times. RESULTS: The mean color difference for each instrument was highest in the OM, followed by the T4, and lowest in the T3 and VE, respectively. The L* and a* value for OM, and the b* value for T4, were significantly different from those for VE (p <0.05). The reproducibility of the instrument was highest in the VE (Fleiss' kappa: 0.95), followed by the T3 (Fleiss' kappa: 0.89), T4 (Fleiss' kappa: 0.87), and OM (Fleiss' kappa: 0.78). CONCLUSIONS: Of the three intraoral scanners, the trueness was best on the T3. The reproducibility of all the instruments was excellent.


Assuntos
Pigmentação em Prótese , Projetos de Pesquisa , Reprodutibilidade dos Testes , Espectrofotometria , Cor
4.
Chemistry ; 28(24): e202200480, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35179269

RESUMO

Defunctionalization of readily available feedstocks to provide alkenes for the synthesis of multifunctional molecules represents an extremely useful process in organic synthesis. Herein, we describe a transition metal-free, simple and efficient strategy to access alkyl 1,2-bis(boronate esters) via regio- and diastereoselective diboration of secondary and tertiary alkyl halides (Br, Cl, I), tosylates, and alcohols. Control experiments demonstrated that the key to this high reactivity and selectivity is the addition of a combination of potassium iodide and N,N-dimethylacetamide (DMA). The practicality and industrial potential of this transformation are demonstrated by its operational simplicity, wide functional group tolerance, and the late-stage modification of complex molecules. From a drug discovery perspective, this synthetic method offers control of the position of diversification and diastereoselectivity in complex ring scaffolds, which would be especially useful in a lead optimization program.


Assuntos
Compostos Inorgânicos , Elementos de Transição , Álcoois , Alcenos , Técnicas de Química Sintética , Ésteres
5.
Chemistry ; 28(3): e202103866, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34713940

RESUMO

A practical and direct method was developed for the production of versatile alkyl boronate esters via transition metal-free borylation of primary and secondary alkyl sulfones. The key to the success of the strategy is the use of bis(neopentyl glycolato) diboron (B2 neop2 ), with a stoichiometric amount of base as a promoter. The practicality and industrial potential of this protocol are highlighted by its wide functional group tolerance, the late-stage modification of complex compounds, no need for further transesterification, and operational simplicity. Radical clock, radical trap experiments, and EPR studies were conducted which show that the borylation process involves radical intermediates.


Assuntos
Ésteres , Sulfonas
6.
Food Microbiol ; 101: 103891, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34579851

RESUMO

In recent years, more attention has been paid to the application of cold plasma (CP) in eliminating foodborne pathogenic bacteria. This work investigated CP effects on inactivation kinetics and cell envelopes of Listeria monocytogenes (L. monocytogenes) and Salmonella Enteritidis (S. Enteritidis). Bacterial suspensions were treated with dielectric barrier discharge atmospheric CP at 75 kV for different treatment time. Three regression models were tested for estimating inactivation kinetics. Reactive species generated in plasma, the appearance and integrity of bacterial cells, the activity and secondary structure of enzymes in the cell envelope, and molecular docking, were measured for evaluating the envelope damages. Results indicated that Log-linear model was suitable for L. monocytogenes and the Weibull model was suitable for S. Enteritidis. S. Enteritidis was more sensitive to short-lived reactive species (such as OH radicals) in plasma than L. monocytogenes, and the cell envelope of S. Enteritidis was more severely damaged (the increased membrane permeability and leakage of intracellular substances) after plasma treatment. Interestingly, compared with S. Enteritidis, the decrease in the activity of enzymes existing in the cell envelope of L. monocytogenes did not contribute significantly to the death of bacteria. Molecular docking further suggested that the decrease in the enzyme activity might be due to the modification of the enzyme, by the interaction between reactive species in plasma (H2O2) and amino acid residues of the enzyme through the hydrogen bond.


Assuntos
Membrana Celular , Temperatura Baixa , Listeria monocytogenes , Gases em Plasma , Salmonella enteritidis , Membrana Celular/efeitos dos fármacos , Peróxido de Hidrogênio , Cinética , Listeria monocytogenes/efeitos dos fármacos , Simulação de Acoplamento Molecular , Gases em Plasma/farmacologia , Salmonella enteritidis/efeitos dos fármacos
7.
Odontology ; 110(4): 759-768, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35212853

RESUMO

To compare the accuracy of visual and instrumental methods for tooth-color matching based on three attributes in the Munsell color system and to investigate the characteristics of intraoral scanners for tooth-color matching. Shades of the cervical, middle, and incisal third region of 130 maxillary anterior teeth were matched visually by an experienced prosthodontist (EP) using Vita classical A1-D4 (VC) and Vita System 3D-Master (V3D) shade guides, and digitally by a spectrophotometer (Vita Easyshade V, VE) and two intraoral scanners (3Shape TRIOS 3, T3; TRIOS 4, T4). VE was used as a reference. The reproducibility of the three test groups was examined by repeating the measurements in triplicate. The overall trueness of the three test groups (from high to low) was T3 > EP > T4 for VC values (p < 0.01), and T3, EP > T4 (p < 0.01) for V3D. The trueness of T3 in incisal regions was lower than cervical and middle regions. When hue or lightness was correct, the mismatched chroma in test groups was smaller than VE (p < 0.01). The repeatability of EP was the poorest (p < 0.01). The color-matching trueness of T3 was higher than EP and T4. The reproducibility of intraoral scanners was better than visual methodology.


Assuntos
Pigmentação em Prótese , Dente , Cor , Reprodutibilidade dos Testes , Espectrofotometria
8.
Chemistry ; 27(31): 8149-8158, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33851475

RESUMO

A nickel/N-heterocyclic carbene (NHC) catalytic system has been developed for the borylation of aryl sulfoxides with B2 (neop)2 (neop=neopentyl glycolato). A wide range of aryl sulfoxides with different electronic and steric properties were converted into the corresponding arylboronic esters in good yields. The regioselective borylation of unsymmetric diaryl sulfoxides was also feasible leading to borylation of the sterically less encumbered aryl substituent. Competition experiments demonstrated that an electron-deficient aryl moiety reacts preferentially. The origin of the selectivity in the Ni-catalyzed borylation of electronically biased unsymmetrical diaryl sulfoxide lies in the oxidative addition step of the catalytic cycle, as oxidative addition of methoxyphenyl 4-(trifluoromethyl)phenyl sulfoxide to the Ni(0) complex occurs selectively to give the structurally characterized complex trans-[Ni(ICy)2 (4-CF3 -C6 H4 ){(SO)-4-MeO-C6 H4 }] 4. For complex 5, the isomer trans-[Ni(ICy)2 (C6 H5 )(OSC6 H5 )] 5-I was structurally characterized in which the phenyl sulfinyl ligand is bound via the oxygen atom to nickel. In solution, the complex trans-[Ni(ICy)2 (C6 H5 )(OSC6 H5 )] 5-I is in equilibrium with the S-bonded isomer trans-[Ni(ICy)2 (C6 H5 )(SOC6 H5 )] 5, as shown by NMR spectroscopy. DFT calculations reveal that these isomers are separated by a mere 0.3 kJ/mol (M06/def2-TZVP-level of theory) and connected via a transition state trans-[Ni(ICy)2 (C6 H5 )(η2 -{SO}-C6 H5 )], which lies only 10.8 kcal/mol above 5.

9.
J Sci Food Agric ; 101(2): 424-432, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32648588

RESUMO

BACKGROUND: Pesticides have been widely used to control pests on agricultural products in China, and large amounts of pesticide residues have caused a serious threat to human health. Thus, developing a high-efficiency pesticide degradation method for fresh vegetables represents a great challenge. The present study investigated the effects of dielectric barrier discharge (DBD) plasma on the degradation of malathion and chlorpyrifos in aqueous solutions and on lettuces. RESULTS: DBD treatment significantly degraded malathion and chlorpyrifos in water and on lettuce. After cold plasma treatment at 80 kV for 180 s, the degradation efficiency of malathion (0.5 µg mL-1 ) and chlorpyrifos (1.0 µg mL-1 ) in aqueous solutions reached 64.6% and 62.7%, respectively. The degradation intermediates were explored by HPLC-mass spectrometry and the DBD plasma degradation pathways of malathion and chlorpyrifos were proposed. There was no significant damage to the quality of lettuces, including color and chlorophyll content, after plasma treatment. Ascorbic acid decreased significantly during long-term treatment with DBD plasma. To ensure the quality of lettuces during processing, the treatment time was shortened to 120 s. Under this condition, the degradation efficiency of malathion (0.5 mg kg-1 ) and chlorpyrifos (1.0 mg kg-1 ) on lettuces was found to be 53.1% and 51.4%. More importantly, we noted that cold plasma treatment significantly inactivated the microorganisms on lettuces. CONCLUSION: The results of the present study show that cold plasma is an effective and safe method for the degradation of organic pesticide residues on fresh vegetables at the same time as retaining the original quality. © 2020 Society of Chemical Industry.


Assuntos
Clorpirifos/química , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos/métodos , Lactuca/efeitos dos fármacos , Malation/química , Resíduos de Praguicidas/química , Folhas de Planta/química , Gases em Plasma/farmacologia , Contaminação de Alimentos/análise , Manipulação de Alimentos/instrumentação , Cinética , Lactuca/química , Folhas de Planta/efeitos da radiação , Poluentes Químicos da Água/química
10.
Chemistry ; 26(71): 17267-17274, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-32697365

RESUMO

We report herein a mild procedure for the copper-catalyzed oxidative cross-coupling of electron-deficient polyfluorophenylboronate esters with terminal alkynes. This method displays good functional group tolerance and broad substrate scope, generating cross-coupled alkynyl(fluoro)arene products in moderate to excellent yields. Thus, it represents a simple alternative to the conventional Sonogashira reaction.

11.
Eur Radiol ; 29(12): 6750-6761, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31286187

RESUMO

OBJECTIVES: The goal of this study was to investigate alterations of white matter (WM) network in patients with left non-lesional temporal lobe epilepsy (nl-TLE) and right nl-TLE to assess the relationship between the white matter network properties and clinical parameters. METHODS: T1 magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) were acquired for 45 participants, including 30 nl-TLE patients (13 left, 17 right) and 15 healthy controls. Diffusion tensor tractography was computed to model the WM structural network. The topologic properties of the WM network were obtained by graph theoretical analysis, and the between-group differences in global and nodal properties of the WM network were examined by network-based statistical analysis (NBS). The relationship between WM network properties and clinical parameters was assessed by Pearson's correlation analysis. RESULTS: NBS results indicated that patients with left and right nl-TLE experienced distinct changes of WM nodal and global network properties compared with HCs. Positive correlation coefficients were found in several regions. The structural disruptions of networks in the two nl-TLE groups were observed to be different in distribution and severity. CONCLUSIONS: This study provides evidence for changes of the WM network topological properties and structural connectivity in nl-TLE patients, which provide useful insights for the understanding of disease mechanisms of TLE and improving treatment outcomes for nl-TLE. KEY POINTS: • This study aims to investigate alterations of white matter (WM) network in patients with non-lesional temporal lobe epilepsy (nl-TLE). • Network-based statistical analysis results indicated that patients with left and right nl-TLE experienced distinct changes of WM nodal and global network properties compared with healthy controls. • This study provides useful insights for the understanding of disease mechanisms of TLE and improving treatment outcomes for nl-TLE.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/patologia , Imageamento por Ressonância Magnética/métodos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adulto , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino
12.
Org Biomol Chem ; 17(27): 6601-6606, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31225579

RESUMO

We report herein the first Cu-catalysed borylation of a wide range of aryl chlorides with different electronic and steric properties using a readily prepared NHC-stabilised Cu catalyst and KOtBu as the base with B2pin2 (pin = pinacolato) as the boron reagent. The aryl chlorides are converted into their corresponding arylboronic esters in good yields. The new procedure shows broad functional group tolerance, and B2neop2 (neop = neopentyl glycolato) can also be applied as the boron reagent.

13.
Eur Arch Otorhinolaryngol ; 276(9): 2411-2417, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31127414

RESUMO

PURPOSE: To explore the correlation between hearing and speech recovery levels after cochlear implantation and examined the preoperative microstructure of auditory pathways and speech centre using DTI. METHODS: (1) Fifty-two SNHL children between 0 and 6 years and 19 age and gender matched normal hearing subjects had received 3.0 T-MRI examination of the brain.FA, axial diffusion coefficient (λ‖), radial diffusion coefficient (λ⊥), and MD values in the lateral lemniscus, inferior colliculus, medial geniculate bodies, auditory radiations, Brodmann areas 41, 42, 22, 44, 45, and 39 were all measured bilaterally. (2) CAP and SIR scores were assessed in fourty-six cochlear implantation children at 6 months post-implant. Correlations among deaf children ages, FA value of bilateral inferior colliculus FA values, BA22, BA44, and postoperative CAP, and SIR scores were analyzed using multiple linear regression. RESULTS: The preoperative standard partial regression age coefficient of deaf children (|bi'| = 0.404) was slightly greater than that of the inferior colliculus (|bi'| = 0.377) FA value. CONCLUSION: Preoperative children ages and inferior colliculus FA values were important factors influencing postoperative CAP score. Inferior colliculus FA value is a vital influencing factor in rehabilitation after cochlear implantation.


Assuntos
Vias Auditivas/fisiopatologia , Implantes Cocleares , Perda Auditiva Neurossensorial/congênito , Vias Auditivas/fisiologia , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Criança , Pré-Escolar , Implante Coclear , Imagem de Difusão por Ressonância Magnética , Feminino , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/reabilitação , Perda Auditiva Neurossensorial/cirurgia , Testes Auditivos , Humanos , Lactente , Modelos Lineares , Masculino , Valores de Referência , Fala , Percepção da Fala , Resultado do Tratamento
14.
J Gen Virol ; 96(Pt 7): 1712-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25752917

RESUMO

The immunological effect of porcine reproductive and respiratory syndrome disease virus (PRRSV) vaccines is thought to be influenced by a variety of host factors, in which antibody-dependent enhancement (ADE) of infection is one crucial factor. Here, we assessed the mechanism of ADE of PRRSV infection. First, we found that subneutralizing serum could induce ADE of PRRSV infection in porcine alveolar macrophages (PAMs). Quantitative PCR, Western blotting and flow cytometry revealed that CD16 is the most abundant Fcγ receptor (FcγR) expressed on the surface of PAMs; thus, the role of CD16 in ADE of PRRSV infection was examined in PAMs. By using functional blocking antibodies, we demonstrated that CD16 is involved in enhanced virus production in PRRSV-antibody immune complex-infected PAMs. Because PAMs co-express different FcγR isoforms, we evaluated the effects of CD16 in FcγR-non-bearing cells by transfection. Using these engineered cells, we found that CD16 could specifically bind to the PRRSV-antibody immune complex and subsequently mediate internalization of the virus, resulting in the generation of progeny virus. We also showed that efficient expression of CD16 required association of the FcR γ-chain. Together, our findings provide significant new insights into PRRSV infection, which can be enhanced by CD16-mediated PRRSV-antibody immune complexes. This CD16-mediated ADE may induce a shift in PRRSV tropism towards CD16-expressing cells, distributing virus to more organs during virus infection.


Assuntos
Anticorpos Facilitadores , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Receptores de IgG/metabolismo , Ligação Viral , Internalização do Vírus , Animais , Complexo Antígeno-Anticorpo/metabolismo , Western Blotting , Linhagem Celular , Citometria de Fluxo , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/virologia , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Suínos
15.
J Virol ; 88(18): 10448-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24965453

RESUMO

UNLABELLED: As a consequence of their effects on ectodomain shedding, members of the A disintegrin and metalloprotease (ADAM) family have been implicated in the control of various cellular processes. Although ADAM family members are also involved in cancer, inflammation, and other pathologies, it is unclear whether they affect porcine reproductive and respiratory syndrome virus (PRRSV) infection. Here, we demonstrate for the first time that inhibition of ADAM17 enhances PRRSV entry in Marc-145 and porcine alveolar macrophages (PAMs). We also demonstrate that the inhibition of ADAM17 upregulates membrane CD163 expression, a putative PRRSV receptor that is exogenously expressed in BHK-21 and endogenously expressed in Marc-145 and PAMs. Furthermore, overexpression of ADAM17 induced downregulation of CD163 expression and a reduction in PRRSV infection, whereas ablation of ADAM17 expression using specific small interfering RNA resulted in upregulation of CD163 expression with a corresponding increase in PRRSV infection. These ADAM17-mediated effects were confirmed with PRRSV nonpermissive BHK-21 cells transfected with CD163 cDNA. Overall, these findings indicate that ADAM17 downregulates CD163 expression and hinders PRRSV entry. Hence, downregulation of ADAM17 particular substrates may be an additional component of the anti-infection defenses. IMPORTANCE: ADAM17 is one of the important membrane-associated metalloproteases that mediate various cellular events, as well as inflammation, cancer, and other pathologies. Here, we investigate for the first time the role of the metalloprotease ADAM17 in PRRSV infection. By using inhibitor and genetic modification methods, we demonstrate that ADAM17 negatively regulate PRRSV entry by regulating its substrate(s). More specifically, ADAM 17 mediates the downregulation of the PRRSV cellular receptor CD163. The reduction in CD163 expression represents another component of the anti-infection response initiated by ADAM17.


Assuntos
Proteínas ADAM/metabolismo , Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Receptores de Superfície Celular/genética , Internalização do Vírus , Proteínas ADAM/genética , Proteína ADAM17 , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Linhagem Celular , Síndrome Respiratória e Reprodutiva Suína/enzimologia , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Receptores de Superfície Celular/metabolismo , Receptores Virais/genética , Receptores Virais/metabolismo , Suínos
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 32(6): 1335-42, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27079110

RESUMO

In order to improve the reliability of cardiac pacemaker contact-less power supply technology, this paper proposes a novel application of wireless feedback voltage stabilizing technology to adjust heart disease patients with inner power supply filter circuit output voltage and current control method, to keep the output voltage stability, and to ensure that the super capacitor and cardiac pacemaker to get a stable power supply. To implement the real-time accurate voltage control with considering the primary and secondary side inductance coupling coefficient changes, the change of the external power supply voltage and load, it is necessary to test thee real-time and accurate output voltage and current value after rectifying filtering. Therefore, based on the chaotic control theory, we adopted method of phase diagram on the basis of the quick observation after rectifying filtering, so that the method of voltage and current could improve the detection time of the circuit. The phase diagram of proposed control method can be divided into 8 segments, and we got 7 zero-extreme points. When these zero-extreme points are detected, according to extreme points of the zero instantaneous values, the corresponding average values of voltage and current were obtained. Simulation and experimental results showed that using the above method can shorten the response time to less than switch devices 1/2 switching cycles, thus validating the effectiveness and feasibility of the proposed detection algorithm.


Assuntos
Fontes de Energia Elétrica , Marca-Passo Artificial , Tecnologia sem Fio , Algoritmos , Retroalimentação , Humanos , Dinâmica não Linear
17.
Neuroscience ; 551: 254-261, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848776

RESUMO

N-acetylaspartate (NAA), choline (Cho) and creatine (Cr) are brain metabolites involved in some key neuronal functions within the brain, such as cognitive function. The aim of this study was to investigate whether Parkinson's disease (PD) with different cognitive status induces regional brain metabolite differences. 38 diagnosed PD patients, including 18 PD patients with normal cognitive (PDN), 20 PD subjects with cognitive impairment (PDMCI) and 25 healthy controls (HC) participated in this study. All subjects underwent a single-voxel proton MR spectroscopy (1H-MRS) on a 3T scanner. 1H-MRS were obtained from bilateral PCC, left thalamus and PFC regions in all subjects, respectively. Region-specific cerebral metabolic alterations existed in PD patients with different cognitive status. PDMCI patients showed a significant reduction of NAA, Cho and tCr in the PCC and left thalamus, compared to healthy controls; whereas lower levels of NAA and Cho in thalamus were found in PDN patients. Moreover, Cho and tCr levels were positively correlated with MMSE scores. Both NAA and tCr in PCC levels were positively correlated with MMSE and MoCA scores. The combination of thalamic and PCC metabolites showed a 75.6% accuracy in distinguishing PDMCI patients from PDN patients. This study provides preliminary evidence that thalamic, PCC and PFC neurometabolic alterations occur in PD patients with cognition decline. Findings of this study indicate that NAA and tCr abnormalities in PCC and thalamus might be used as a biomarker to track cognitive decline in Parkinson's disease in clinical settings.

18.
Sch Psychol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934898

RESUMO

The increase in social media mental health (MH) campaigns provides an opportunity to improve awareness and attitudes toward MH. However, racial disparities remain in these social media campaigns. Black youth who participated in MH social media campaigns reported lower levels of improvement in stigma and help-seeking than their White peers. We employed a youth participatory action research (YPAR) process to expand on a previous community-wide MH social media campaign (A. Thompson et al., 2021), focusing on a Central Midwest community. We studied Black adolescents' perceptions of MH stigma and help-seeking to determine essential features of a culturally responsive MH social media campaign for Black youth. With a lead youth-research collaborator, the research team designed the following two-staged study. The first stage consisted of four semistructured focus group interviews (FGIs) (N = 20), analyzed by using a rapid analysis strategy to obtain results for the development of the campaign. In the second stage, using YPAR's iterative and action-based process, five youth researchers collaborated with the research team on the campaign's design. Following the two stages, the researcher's thematic analysis resulted in three themes: (a) broadening horizons for campaign designers and MH professionals; (b) considering mistrust of schools and school personnel; and (c) diverse experiences, sustainability, and accessibility in a campaign. Findings indicated that while culturally responsive social media campaigns to promote MH can be designed, mistrust of adults in schools is likely to hinder the impact of such campaigns. Implications for school psychology practice and research are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

19.
Sci Rep ; 13(1): 14241, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648724

RESUMO

Few comparative studies have assessed metabolic brain changes in cognitive impairment among neurodegenerative disorders, and the posterior cingulate cortex (PCC) is a metabolically active brain region with high involvement in multiple cognitive processes. Therefore, in this study, metabolic abnormalities of the PCC were compared in patients with mild cognitive impairment (MCI) due to Parkinson's disease (PD) or Alzheimer's disease (AD), as examined by proton magnetic resonance spectroscopy (1H-MRS). Thirty-eight patients with idiopathic PD, including 20 with mild cognitive impairment (PDMCI) and 18 with normal cognitive function (PDN), 18 patients with probable mild cognitive impairment (ADMCI), and 25 healthy elderly controls (HCs) were recruited and underwent PCC 1H-MRS scans. Compared with HCs, patients with PDMCI exhibited significantly reduced concentrations of N-acetyl aspartate (NAA), total NAA (tNAA), choline (Cho), glutathione (GSH), glutamate + glutamine (Glx) and total creatine (tCr), while ADMCI cases exhibited significantly elevated levels of myo-inositol (Ins) and Ins/tCr ratio, as well as reduced NAA/Ins ratio. No significant metabolic changes were detected in PDN subjects. Compared with ADMCI, reduced NAA, Ins and tCr concentrations were detected in PDMCI. Besides, ROC curve analysis revealed that tCr concentration could differentiate PDMCI from PDN with an AUC of 0.71, and NAA/Ins ratio could differentiate patients with MCI from controls with normal cognitive function with an AUC of 0.74. Patients with PDMCI and ADMCI exhibited distinct PCC metabolic 1H-MRS profiles. The findings suggested cognitively normal PD patients with low NAA and tCr in the PCC might be at risk of preclinical PDMCI, and Ins and/or NAA/MI ratio in the PCC should be reconsidered a possible biomarker of preclinical MCI in clinical practice. So, comparing PCC's 1H-MRS profiles of cognitive impairment among neurodegenerative illnesses may provide useful information for better defining the disease process and elucidate possible treatment mechanisms.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Parkinson , Idoso , Humanos , Doença de Parkinson/complicações , Giro do Cíngulo/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Creatina , Glutationa , Receptores de Antígenos de Linfócitos T
20.
Cell Death Dis ; 14(3): 179, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36872411

RESUMO

Cholesterol metabolism plays a critical role in the progression of hepatocellular carcinoma (HCC), but it is not clear how cholesterol metabolism is regulated. The tubulin beta class I genes (TUBBs) are associated with the prognosis of many different cancers. To confirm the function of TUBBs in HCC, the Kaplan-Meier method and Cox analyses were performed using TCGA and GSE14520 datasets. A higher expression of TUBB2B is an independent prognostic factor for shorter over survival in HCC patients. Deletion of TUBB2B in hepatocytes inhibits proliferation and promotes tumor cell apoptosis, while over-expression of TUBB2B has the opposite function. This result was confirmed in a mouse xenograft tumor model. Mechanistically, TUBB2B induces the expression of CYP27A1, an enzyme responsible for the conversion of cholesterol to 27-hydroxycholesterol, which leads to the up-regulation of cholesterol and the progression of HCC. In addition, TUBB2B regulates CYP27A1 via human hepatocyte nuclear factor 4alpha (HNF4A). These findings indicated that TUBB2B functions as an oncogene in HCC, and plays a role in promoting cell proliferation and anti-apoptosis through targeting HNF4A/CYP27A1/cholesterol.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Apoptose , Colestanotriol 26-Mono-Oxigenase , Sistema Enzimático do Citocromo P-450 , Modelos Animais de Doenças , Fator 4 Nuclear de Hepatócito , Hepatócitos , Oncogenes , Tubulina (Proteína)
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