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1.
J Transl Med ; 22(1): 692, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075464

RESUMO

BACKGROUND: Molecularly targeted therapies have recently become a hotspot in the treatment of LUAD, with ongoing efforts to identify new effective targets due to individual variability. Among these potential targets, the mitochondrial transcription elongation factor (TEFM) stands out as a crucial molecule involved in mitochondrial synthetic transcriptional processing. Dysregulation of TEFM has been implicated in the development of various diseases; however, its specific role in LUAD remains unclear. METHODS: We conducted a comprehensive analysis of TEFM expression in LUAD, leveraging data from the TCGA database. Subsequently, we validated these findings using clinical specimens obtained from the First Affiliated Hospital of Soochow University, employing western blotting and qRT-PCR techniques. Further experimental validation was performed through the transfection of cells with TEFM overexpression, knockdown, and knockout lentiviruses. The effects of TEFM on LUAD were evaluated both in vitro and in vivo using a range of assays, including CCK-8, colony formation, EdU incorporation, Transwell migration, Tunel assay, flow cytometry, JC-1 staining, and xenograft tumour models. RESULTS: Our investigation uncovered that TEFM exhibited elevated expression levels in LUAD and exhibited co-localization with mitochondria. Overexpression of TEFM facilitated malignant processes in LUAD cells, whereas its silencing notably curbed these behaviors and induced mitochondrial depolarization, along with ROS production, culminating in apoptosis. Moreover, the absence of TEFM substantially influenced the expression of mitochondrial transcripts and respiratory chain complexes. Results from nude mouse xenograft tumors further validated that inhibiting TEFM expression markedly hindered tumor growth. CONCLUSION: TEFM promotes LUAD malignant progression through the EMT pathway and determines apoptosis by affecting the expression of mitochondrial transcripts and respiratory chain complexes, providing a new therapeutic direction for LUAD-targeted therapy.


Assuntos
Apoptose , Mitocôndrias , Fatores de Elongação da Transcrição , Humanos , Animais , Mitocôndrias/metabolismo , Linhagem Celular Tumoral , Fatores de Elongação da Transcrição/metabolismo , Fatores de Elongação da Transcrição/genética , Apoptose/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Camundongos Nus , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/terapia , Movimento Celular , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Terapia de Alvo Molecular , Feminino , Masculino
2.
Angew Chem Int Ed Engl ; : e202407353, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953247

RESUMO

To explore the mechanisms and therapeutic strategies for G-quadruplex (G4) mediated diseases, it is crucial to manipulate and intervene in intracellular G4 structures using small molecular tools. While hundreds of G4 stabilizers have been developed, there is a significant gap in the availability of G4 unwinding agents. Here, we propose a strategy to disrupt G-quadruplexes by forming G-C hydrogen bonds with chemically modified cytidine trimers. We validated a good G4 unwinder, the 2'-F cytidine trimer (2'-F C3). 2'-F C3 does not inhibit cell growth nor cause severe DNA damage at a concentration below 10 µM. Moreover, 2'-F C3 does not affect gene transcription nor RNA splicing, while it significantly enhances the translation of G4-containing mRNA and upregulates RNA splicing, RNA processing and cell cycle pathways. The discovery of this G4 unwinder provides a functional tool for the chemical modulation of G4s in living cells.

3.
J Am Chem Soc ; 145(33): 18578-18590, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37553999

RESUMO

Bimolecular or tetramolecular G-quadruplexes (GQs) are predominantly self-assembled by the same sequence-identical G-rich oligonucleotides and usually remain inert to the strand displacement reaction (SDR) with other short G-rich invading fragments of DNA or RNA. Appealingly, in this study, we demonstrate that a parallel homomeric bimolecular GQ target of Tub10 d(CAGGGAGGGT) as the starting reactant, although completely folded in K+ solution and sufficiently stable (melting temperature of 57.7 °C), can still spontaneously accept strand invasion by a pair of short G-rich invading probes of P1 d(TGGGA) near room temperature. The final SDR product is a novel parallel heteromeric trimolecular GQ (tri-GQ) of Tub10/2P1 reassembled between one Tub10 strand and two P1 strands. Here we present, to the best of our knowledge, the first NMR solution structure of such a discrete heteromeric tri-GQ and unveil a unique mode of two probes vs one target in mutual recognition among G-rich canonical DNA oligomers. As a model system, the short invading probe P1 can spontaneously trap G-rich target Tub10 from a Watson-Crick duplex completely hybridized between Tub10 and its fully complementary strand d(ACCCTCCCTG). The Tub10 sequence of d(CAGGGAGGGT) is a fragment from the G-rich promoter region of the human ß2-tubulin gene. Our findings provide new insights into the Hoogsteen pairing-based SDR between a GQ target and double invading probes of short G-rich DNA fragments and are expected to grant access to increasingly complex architectures in GQ-based DNA nanotechnology.


Assuntos
Quadruplex G , Humanos , DNA/química , Oligonucleotídeos/química , Recombinação Genética , RNA
4.
Nucleic Acids Res ; 49(18): 10717-10734, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34500466

RESUMO

The final 3'-terminal residue of the telomeric DNA G-overhang is inherently less precise. Here, we describe how alteration of the last 3'-terminal base affects the mutual recognition between two different G-rich oligomers of human telomeric DNA in the formation of heteromolecular G-quadruplexes (hetero-GQs). Associations between three- and single-repeat fragments of human telomeric DNA, target d(GGGTTAGGGTTAGGG) and probe d(TAGGGT), in Na+ solution yield two coexisting forms of (3 + 1) hybrid hetero-GQs: the kinetically favourable LLP-form (left loop progression) and the thermodynamically controlled RLP-form (right loop progression). However, only the adoption of a single LLP-form has been previously reported between the same probe d(TAGGGT) and a target variant d(GGGTTAGGGTTAGGGT) having one extra 3'-end thymine. Moreover, the flanking base alterations of short G-rich probe variants also significantly affect the loop progressions of hetero-GQs. Although seemingly two pseudo-mirror counter partners, the RLP-form exhibits a preference over the LLP-form to be recognized by a low equivalent of fluorescence dye thioflavin T (ThT). To a greater extent, ThT preferentially binds to RLP hetero-GQ than with the corresponding telomeric DNA duplex context or several other representative unimolecular GQs.


Assuntos
Benzotiazóis , Corantes Fluorescentes , Quadruplex G , Telômero/química , DNA/química , Humanos , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Sequências Repetitivas de Ácido Nucleico
5.
Nucleic Acids Res ; 49(4): 2306-2316, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33524157

RESUMO

Vast G-quadruplexes (GQs) are primarily folded by one, two, or four G-rich oligomers, rarely with an exception. Here, we present the first NMR solution structure of a trimolecular GQ (tri-GQ) that is solely assembled by the self-trimerization of d(GTTAGG), preferentially in Na+ solution tolerant to an equal amount of K+ cation. Eight guanines from three asymmetrically folded strands of d(GTTAGG) are organized into a two-tetrad core, which features a broken G-column and two width-irregular grooves. Fast strand exchanges on a timescale of second at 17°C spontaneously occur between folded tri-GQ and unfolded single-strand of d(GTTAGG) that both species coexist in dynamic equilibrium. Thus, this tri-GQ is not just simply a static assembly but rather a dynamic assembly. Moreover, another minor tetra-GQ that has putatively tetrameric (2+2) antiparallel topology becomes noticeable only at an extremely high strand concentration above 18 mM. The major tri-GQ and minor tetra-GQ are considered to be mutually related, and their reversible interconversion pathways are proposed accordingly. The sequence d(GTTAGG) could be regarded as either a reading frame shifted single repeat of human telomeric DNA or a 1.5 repeat of Bombyx mori telomeric DNA. Overall, our findings provide new insight into GQs and expect more functional applications.


Assuntos
DNA/química , Quadruplex G , Potássio/química , Sódio/química , Animais , Bombyx/genética , Temperatura Alta , Humanos , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Telômero/química
6.
Angew Chem Int Ed Engl ; 62(47): e202314213, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37794843

RESUMO

Poly(heptazine imide) (PHI) salts, as crystalline carbon nitrides, exhibit high photocatalytic activity and are being extensively researched, but its photochemical instability has not drawn researchers' attention yet. Herein, sodium PHI (PHI-Na) ultrathin nanosheets with increased crystallinity, synthesized by enhancing contact of melamine with NaCl functioning as a structure-induction agent and hard template, exhibits improved photocatalytic hydrogen evolution activity, but low photochemical stability, owing to Na+ loss in the photocatalytic process, which, interestingly, can be enhanced by the common ion effect, e.g., addition of NaCl that is also able to remarkably increase the photoactivity with the apparent quantum yield at 420 nm reaching 41.5 %. This work aims at attracting research peers' attention to photochemical instability of PHI salts and provides a way to enhance their crystallinity.

7.
J Phys Chem A ; 119(34): 9027-36, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26243653

RESUMO

Liquid­liquid phase separation was observed in aqueous MgSO4 solutions with excess H2SO4 at elevated temperatures; the aqueous MgSO4/H2SO4 solutions separated into MgSO4-rich droplets (fluid F1) and a MgSO4-poor phase (fluid F2) during heating. The phase separation temperature increases with SO4(2­)/Mg2+ ratio at a constant MgSO4 concentration. At a MgSO4/H2SO4 ratio of 5, the liquid­liquid phase separation temperature decreases with an increase in MgSO4 concentration up to ∼1.0 mol/kg and then increases at higher concentrations, showing a typical macroscale property of polymer solutions with a lower critical solution temperature (LCST) of ∼271.4 °C. In situ Raman spectroscopic analyses show that the MgSO4 concentration in fluid F1 increases with an increase in temperature, whereas that in fluid F2 decreases with an increase in temperature. In addition, HSO4(­), which does not readily form complexes with Mg(2+), tends to accumulate in fluid F2. Analyses of the v1(SO4(2­)) bands confirmed the presence of four-sulfate species of unassociated SO4(2­) (∼980 cm(­1)), contact ion pairs (CIPs; ∼995 cm(­1)), and triple ion pairs (TIPs; ∼1005 cm(­1)) in aqueous solution, and more complex ion pair chain structure (∼1020 cm(­1)) in fluid F1. Comparison of the sulfate species in fluids F1 and F2 at 280 °C suggests that SO4(2­) in fluid F2 is less associated with Mg(2+). On the basis of in situ visual and Raman spectroscopic observations, we suggest that the formation of the complex Mg(2+)­SO4(2­) ion association might be responsible for the liquid­liquid phase separation. In addition, Raman spectroscopic analyses of the OH stretching bands indicate that the hydrogen bonding in fluid F1 is stronger than that in fluid F2, which might be ascribed to the increasing probability of collision of H2O with Mg(2+) and SO4(2­) in fluid F1.


Assuntos
Sulfato de Magnésio/química , Análise Espectral Raman , Temperatura , Ligação de Hidrogênio , Extração Líquido-Líquido , Sulfato de Magnésio/isolamento & purificação
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123774, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38141503

RESUMO

Carbonaceous fluid within mineral-hosted inclusions provides important information for carbon cycle in deep Earth. In addition to CH4 and CO2, heavy hydrocarbons (e.g., C2H6 and C3H8) are frequently observed in carbonaceous fluid inclusions (i.e, wet gas inclusions with C1/∑Ci < 0.95). However, determination of the composition of such complex volatiles is difficult based on traditional microthermometric measurements. Here we carried out experimental calibrations on Raman spectroscopic measurements of the pressure (P) and composition of the CH4 ± C2H6 ± C3H8 ± H2S system at room temperature and 0.1-130 MPa. We confirmed that the C-H symmetric stretching vibration band of CH4 [ν1(CH4), ∼2917 cm-1] shifted to lower wavenumber with rising pressure, thus the P-ν1(CH4) relationship could be applied to calculate the pressure of wet gas. It should be noted that the presence of C2+ and/or H2S will shift the [ν1(CH4)] to lower wavenumber at constant pressure (with the order of C3H8 ≥ H2S > C2H6). Obviously, the P-ν1(CH4) relationship derived from pure CH4 system could not be simply applied to wet gas inclusion, otherwise the pressure would be overestimated. To avoid the overlap of the C-H vibrations of CH4, C2H6 and C3H8, the peak areas and peak heights of the overtone vibration of CH4 [2ν4(CH4), ∼2580 cm-1], C-C symmetric stretching vibrations of C2H6 [ν3(C2H6), ∼995 cm-1] and C3H8 [ν8(C3H8), ∼868 cm-1], and S-H symmetric stretching vibration of H2S [ν1(H2S), ∼2612 cm-1] were fitted using Gaussian + Lorentz functions. The obtained peak areas and peak heights were then used to calculate the Raman quantification factors (F factor and G factor, respectively) of C2H6, C3H8 and H2S relative to CH4, respectively. Both the F factor and G factor increased with rising pressure, whereas the FC2H6, FC3H8 and GH2S kept nearly constant at ∼5.69, 6.39 and 153.8, respectively in high pressure gas mixtures (e.g., >30 MPa). Therefore, for inclusions with higher internal pressure, the molar ratio of CH4, C2H6, C3H8 and H2S could be determined by the aforementioned F and G factors. This method was applied to the calcite-hosted single-phase gas inclusions in the Upper Permian Changxing Formation carbonate reservoir from the eastern Sichuan Basin (South China). Our results indicated that the trapping pressure would be obviously overestimated if the presence of heavy hydrocarbons was not taken into account.

9.
BMJ Open ; 14(2): e077078, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341212

RESUMO

OBJECTIVES: To investigate the prevalence of depression and anxiety symptoms among older adults in an urban district in China, as well as their associated factors. DESIGN: Cross-sectional study. SETTING: General communities in Shenzhen, Guangdong, China. PARTICIPANTS: A total of 5372 community-dwelling older adults aged 65 years or older were initially recruited. Ultimately, 5331 participants met the inclusion criteria and were included in this study. METHODS: Participants completed a sociodemographic questionnaire, along with assessments including the Patient Health Questionnaire-9, Generalised Anxiety Scale-7, UCLA Loneliness Simplification Scale, Insomnia Severity Index Scale (ISI), Community Dementia Brief Screening Scale and the 8-item Dementia Screening Questionnaire. Statistical analyses included the Shapiro-Wilk test, independent t-test, Wilcoxon rank test, χ2 test and univariate and multivariate linear regression analysis. RESULTS: The prevalence of depression and anxiety symptoms among older adults in Shenzhen communities was 10.4% and 11.3%, respectively. In multivariate analysis, age (B=-0.01, p<0.05), relatively poor health status in the past year (B=1.00, p<0.01), poor health status in the past year (B=2.40, p<0.01), ISI score (B=0.21, p<0.01), -item Ascertain Dementia Questionnaire (AD8) score (B=0.22, p<0.01), UCLA Loneliness Scale (ULS) score (B=0.24, p<0.01) were significantly associated with the severity of depression symptom, Compared with their respective reference categories, relatively poor health status in the past year (B=0.50, p<0.01), poor health status in the past year (B=1.32, p<0.01), ISI score (B=0.23, p<0.01), sleep duration (B=0.05, p<0.01), AD8 score (B=0.21, p<0.01), Community Screening Instrument for Dementia score (B=0.13, p<0.01), ULS score (B=0.22, p<0.01) were significantly associated with the severity of anxiety symptom. CONCLUSIONS: We observed a high prevalence of depression and anxiety symptoms among older adults in this study. The existing welfare system and infrastructure should remain and targeted mental health programmes addressing the identified risk factors should be proposed.


Assuntos
Demência , Depressão , Humanos , Idoso , Estudos Transversais , Prevalência , Depressão/psicologia , Ansiedade/psicologia , China/epidemiologia , Demência/epidemiologia
10.
Carbohydr Polym ; 342: 122419, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39048244

RESUMO

To investigate the differences of nanocelluloses with various morphologies, ammonium persulphate (APS) oxidation, H3PO4 dissolution and regeneration, and ball milling combined with 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) as a medium were applied to isolate cellulose nanocrystals (MCNCs), cellulose nanospheres (MCNSs) and cellulose fibrils (MCNFs) from millet bran. The structure, properties, and formation mechanism of three nanocelluloses were comparatively investigated by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, atomic force microscope, scanning electronic microscope, and emulsifying ability evaluation. MCNCs had needle-like structures due to the removal of amorphous regions, MCNFs appeared fibrous structures due to swelling and mechanical force, and MCNSs displayed spherical structures through self-assembly. MCNCs and MCNFs were confirmed to exhibit cellulose I structures with crystallinities of 61.24 % and 50.09 %, respectively. MCNSs showed the highest crystallinity of 68.41 % with a cellulose II structure. MCNFs and MCNSs exhibited higher initial decomposition temperatures, while MCNCs showed the highest residual mass. MCNFs suspension showed the highest apparent viscosity, while MCNSs suspension demonstrated superior dispersion. MCNSs-emulsion displayed the smallest droplet size, and MCNFs-emulsion exhibited the highest viscosity. This study reveals the formation mechanisms and relationship between morphologies and properties of three millet bran nanocelluloses, providing a theoretical basis for their application.

11.
Int J Biol Macromol ; 267(Pt 1): 131217, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552683

RESUMO

Ultrasonic assisted acetic acid hydrolysis was applied to prepare starch nanocrystals (SNCs) from native starches with different crystalline structures (A, B, and C types). The structure properties, morphology, Pickering emulsion stability and curcumin deliver capacity of both SNCs and native starches were investigated and compared. Compared with native starches, SNCs showed smaller size and higher crystallinity. The size of SNCs varied with different crystalline types, with C-type starch exhibiting the smallest SNCs (107.4 nm), followed by A-type (113.8 nm), and B-type displaying the largest particle size (149.0 nm). SNCs-Pickering emulsion showed enhanced stability with smaller emulsion droplets, higher static stability, and denser oil/water interface. SNCs-Pickering emulsions displayed higher curcumin loading efficiency (53.53 %-61.41 %) compared with native starch-Pickering emulsions (13.93 %-19.73 %). During in vitro digestion, SNCs-Pickering emulsions proved to be more proficient in protecting and prolonging the biological activity of curcumin due to their smaller size and better interfacial properties. These findings demonstrated the potential of SNCs for application in Pickering emulsion and delivery of bioactive components.


Assuntos
Ácido Acético , Curcumina , Emulsões , Nanopartículas , Amido , Curcumina/química , Amido/química , Emulsões/química , Nanopartículas/química , Ácido Acético/química , Tamanho da Partícula , Estabilidade de Medicamentos , Hidrólise , Cristalização , Ondas Ultrassônicas , Portadores de Fármacos/química
12.
Food Res Int ; 191: 114706, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059959

RESUMO

Selenium (Se) biofortification during the growth process of mung bean is an effective method to improve the Se content and quality. However, the effect of Se biofortification on the physicochemical properties of mung bean protein is unclear. The objective of this study was to clarify the changes in the composition, Se forms, particle structure, functional properties, thermal stability, and gel properties of mung bean protein at four Se application levels. The results showed that the Se content of mung bean protein increased in a dose-dependent manner, with 7.96-fold (P1) and 8.52-fold (P2) enhancement at the highest concentration. Exogenous Se application promotes the conversion of inorganic Se to organic Se. Among them, selenomethionine (SeMet) and methyl selenocysteine (MeSeCys) replaced Met and Cys through the S metabolic pathway and became the dominant organic Se forms in Se-enriched mung bean protein, accounting for more than 80 % of the total Se content. Exogenous Se at 30 g/hm2 significantly up-regulated protein content and promoted the synthesis of sulfur-containing protein components and hydrophobic amino acids in the presence of increased levels of SeMet and MeSeCys. Meanwhile, Cys and Met substitution altered the sulfhydryl groups (SH), ß-sheets, and ß-turns of protein. The particle size and microstructural characteristics depend on the protein itself and were not affected by exogenous Se. The Se-induced increase in the content of hydrophobic amino acids and ß-sheets synergistically increases the thermal stability of the protein. Moderate Se application altered the functional properties of mung bean protein, which was mainly reflected in the significant increase in oil holding capacity (OHC) and foaming capacity (FC). In addition, the increase in SH and ß-sheets induced by exogenous Se could alter the protein intermolecular network, contributing to the increase in storage modulus (G') and loss modulus (G″), which resulted in the formation of more highly elastic gels. This study further promotes the application of mung bean protein in the field of food processing and provides a theoretical basis for the extensive development of Se-enriched mung bean protein.


Assuntos
Proteínas de Plantas , Reologia , Selênio , Selenometionina , Vigna , Vigna/química , Vigna/crescimento & desenvolvimento , Selênio/química , Selenometionina/química , Proteínas de Plantas/química , Géis/química , Selenocisteína/química , Selenocisteína/análogos & derivados , Biofortificação , Interações Hidrofóbicas e Hidrofílicas , Temperatura Alta , Alimentos Fortificados/análise
13.
J Cardiothorac Surg ; 19(1): 371, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918857

RESUMO

BACKGROUND: Pleural solitary fibrous tumors (pSFTs) are rare mesenchymal pleural tumors with rich vascularity. Surgical resection is the cornerstone of pSFTs treatment, requiring careful preoperative imaging to delineate lesion extent and vascular supply including contrast-enhanced computed tomography and other examinations depending on its size and characteristics. CASE PRESENTATION: The patient was a 34-year-old female with a mass measuring approximately 67 × 42 × 65 mm in the left posterior mediastinum. Intraoperatively, the mass demonstrated rich vascularity. Two veins originating from the abdominal cavity entered the lower pole, one converged from the superior pole, draining into the brachiocephalic vein. Additionally, two arteries arose directly from the descending aorta, while several veins drained into the intercostal veins. In response to unexpected intraoperative vascular findings, vascular clips and silk threads were used to ligate them. Subsequently, the tumor was successfully dissected, with approximately 600 ml of blood loss recorded during the 4-hour surgery. The patient exhibited a satisfactory postoperative recovery, and follow-up spanning over six months revealed no indications of recurrence or metastasis. CONCLUSIONS: We firstly present a case of successful resection of a pSFT in a 34-year-old woman with a distinct feeding vessel arising from the descending aorta and describe the related surgical procedures. This case highlights preoperative evaluation of mass vascularity based on contrast-enhanced computed tomography. When blood supply is challenging to clarify, angiography can offer additional details, especially for giant pSFTs. Despite this, thorough intraoperative exploration remains essential to detect unexpected vessels. Appropriate interventions should be customized based on the vascular origins and the surrounding anatomical structures.


Assuntos
Aorta Torácica , Humanos , Feminino , Adulto , Aorta Torácica/cirurgia , Aorta Torácica/diagnóstico por imagem , Tumor Fibroso Solitário Pleural/cirurgia , Tumor Fibroso Solitário Pleural/diagnóstico por imagem , Tomografia Computadorizada por Raios X
14.
Food Chem ; 439: 138134, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064837

RESUMO

Ethanol-acid penetration and drying-heating treatment was developed to shorten the preparation time and improve the quality of starch nanocrystals (SNCs). After treatment by optimized parameters, including 40 % ethanol solution, 10.6 mM chloric acid, and heating time of 1.5 h or 2.0 h, the starches exhibited weakened internal structure and relatively complete crystalline structure. Compared with the regular preparation of only acid hydrolysis, the regular final yield (8.5 % after 5 days) was reached in 48 h and 12 h of the starch heated at 1.5 h and 2.0 h, respectively. The micromorphology, molecular weight, and crystalline structure evaluation demonstrated that the collected nanoparticles were indeed SNCs with smaller size and higher relative crystallinity than regular SNCs. Further analysis found that the SNCs had better crystalline lamellae, higher thermal stability, and lower proportion of phosphorus and sulfur atoms than regular SNCs. This provided a potential method for the high-efficiency preparation of SNCs.


Assuntos
Nanopartículas , Amido , Amido/química , Etanol , Calefação , Tamanho da Partícula , Ácidos , Nanopartículas/química
15.
J Affect Disord ; 351: 661-670, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309483

RESUMO

BACKGROUND: Observational studies cannot accurately infer the causal associations between oral health status and psychiatric disorders. METHODS: We conducted univariate and multivariate Mendelian randomization (MR) analyses using single nucleotide polymorphisms (SNPs) associated with eight oral health statuses (periodontitis, DMFS, Nteeth, toothache, loose teeth, painful gums, bleeding gums, and mouth ulcers) and four psychiatric disorders (Schizophrenia, Major Depressive Disorder (MDD), anxiety and stress-related disorder (ASRD), and Bipolar Disorder (BIP)) as instrumental variables. Genetic data were sourced from the Gene-lifestyle interactions in dental endpoints (GLIDE), UK Biobank, Psychiatric Genomics Consortium (PGC), and Lundbeck Foundation Initiative for Integrative Psychiatric Research (iPSYCH). The inverse variance-weighted (IVW) approach, supported by a comprehensive sensitivity analysis, was employed. RESULTS: Genetically predicted mouth ulcers were significantly linked to higher MDD (OR = 2.17, 95 % CI: 1.33--3.54, P< 0.01) and BIP risks (OR = 2.25, 95 % CI: 1.22-4.15, P = 0.01). BIP heightened bleeding gums risk (OR = 1.01, 95 % CI: 1.00-1.01, P < 0.01). These associations were adjusted for smoking status and alcohol consumption. Painful gums were significantly associated with MDD risk (OR = 96.48, 95 % CI: 2.66-3495.28, P = 0.01), while MDD raised periodontitis risk (OR = 2.15, 95 % CI: 1.24-3.75, P = 0.01), both confounded by smoking and alcohol. Relatively small effects between several variables, while others could not withstand correction for multiple tests. LIMITATIONS: The sample size and limitation to European populations limits the study generalizability. CONCLUSIONS: This study provide evidence of possible causal relationships between several oral health conditions and mental illness. Focusing on oral health and valuing mental health are important for each other and overall health.


Assuntos
Transtorno Depressivo Maior , Transtornos Mentais , Úlceras Orais , Periodontite , Humanos , Saúde Bucal , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Análise da Randomização Mendeliana , Transtornos Mentais/epidemiologia , Transtornos Mentais/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
16.
Sci Rep ; 13(1): 21348, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049524

RESUMO

Rich in renewable resources, extensive acreage, and bioenergy expertise, Brazil, however, has no established strategies for sustainable aviation fuels, particularly e-kerosene. We extend the lens from the often-studied economic feasibility of individual e-kerosene supply chains to a system-wide perspective. Employing energy system analyses, we examine the integration of e-kerosene production into Brazil's national energy supplies. We introduce PyPSA-Brazil, an open-source energy system optimisation model grounded in public data. This model integrates e-kerosene production and offers granular spatial resolution, enabling federal-level informed decisions on infrastructure locations and enhancing transparency in Brazilian energy supply scenarios. Our findings indicate that incorporating e-kerosene production can bolster system efficiency as Brazil targets a carbon-neutral electricity supply by 2050. The share of e-kerosene in meeting kerosene demand fluctuates between 2.7 and 51.1%, with production costs varying from 113.3 to 227.3 €/MWh. These costs are influenced by factors such as biokerosene costs, carbon pricing, and export aspirations. Our findings are relevant for Brazilian policymakers championing aviation sustainability and offer a framework for other countries envisioning carbon-neutral e-kerosene production and export.

17.
Food Chem ; 412: 135536, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36708668

RESUMO

Starch nanocrystals (SNCs) were prepared from waxy rice starch via sulfuric acid hydrolysis. The objective focused on the following: i) the hydrolysis kinetics and structural properties of SNCs; ii) the effects of differential centrifugation on the yield and size distribution of SNCs. The hydrolysis was divided into a rapid hydrolysis stage in the initial two days and a slow hydrolysis stage after two days. During the two-day hydrolysis, the average diameter of SNCs reached 244 nm. After two days of hydrolysis, the degree of crystallinity, crystallite size, and melting temperature and enthalpy increased. The proportion of A-branched chains decreased, whereas the proportion of B1-branched chains and molecular weight did not change considerably. Thus, the reaction in the slow hydrolysis stage could be considered as the surface modification and gradual release of SNCs. Furthermore, SNCs with a small size and high charge density could be used for differential centrifugation.


Assuntos
Nanopartículas , Oryza , Amido/química , Tamanho da Partícula , Amilopectina , Hidrólise , Nanopartículas/química , Centrifugação
18.
Int J Biol Macromol ; 235: 123735, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36806775

RESUMO

Starch nanoparticles (SNPs) were produced by nanoprecipitation combined with ultrasonication with the use of different starches (corn, potato and sago starch) and used to stabilize Pickering emulsions. The orthogonal experiment was used to optimize preparation conditions of gelatinization pretreatment duration of 30 min, ultrasonic power of 600 W, and ultrasonic time of 40 min. Compared with native starch, the SNPs were spherical in shape and displayed a V-type crystalline structure with low relative crystallinity and higher degree of double-helix. Compared with native starch-Pickering emulsion, the SNP-Pickering emulsion had a smaller droplet size, more uniform distribution, clearer oil/water interface, and higher static stability of droplets. The sago SNP-Pickering emulsion had the great gelatinous structure and emulsion stability. In addition, the SNP-Pickering emulsion had the better loading efficiency and controlled release performance of curcumin. Meanwhile, the bioavailability of curcumin in sago SNP-Pickering emulsion was highest.


Assuntos
Curcumina , Nanopartículas , Emulsões/química , Amido/química , Nanopartículas/química , Grão Comestível , Tamanho da Partícula
19.
ACS Appl Mater Interfaces ; 15(26): 31502-31513, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37345282

RESUMO

The photoexcited charge separation efficiency of photocatalysts is generally considered as the key factor for enhancement of their photocatalytic activity, and sometimes, their photoabsorption capability and interfacial reaction kinetics play a key part, but the role of interfacial affinity of photocatalysts with substrates was rarely researched systematically. Herein, nitrogen vacancy-modified polymeric carbon nitride porous nanotubes (PCNpts) were simply synthesized, using tartaric acid as a crosslinking and corrosion agent, and exhibit a remarkable increment in surface area, wettability, photoabsorption and charge separation capability, and photocatalytic activity in water splitting to produce H2, but, interestingly, exhibit substrate-dependent variation of photoactivity in contaminant degradation, compared with bulk PCN. More interestingly, the interfacial affinity of PCNpts and PCN with contaminants and H2O, rather than photoabsorption and charge separation capability, is confirmed to dominate their photoactivity.

20.
Int J Biol Macromol ; 253(Pt 1): 126604, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652338

RESUMO

To prevent starch nanocrystals (SNCs) that are generated at an early stage from being hydrolyzed excessively, this study proposed a new separation method, named "neutral dispersion and acidic precipitation." SNCs were prepared from waxy potato starch by sulfuric acid hydrolysis. Based on the results of kinetics and molecular weight, the hydrolysis was divided into three stages, e.g., rapid (initial 1 day), medium (subsequent 1 day) and slow stage (2-5 days). The rapid and medium stages were related to the degradation of amorphous region in starch, and the slow stage mainly referred to SNC release. Therefore, the method was developed to separate SNCs at the slow stage. After centrifugation at 6000 rpm, large particles were removed from the SNC suspension under pH 7. The SNCs with small average size and crystallite size, high relative crystallinity (RC), and high dispersion stability in the supernatant were retained and were then precipitated entirely under pH 5, because pH 5 led to the reduction of dispersion stability of SNCs. Meanwhile, the hydrothermal and dry-thermal stability of separated SNCs were significantly promoted. The separation method has the potential in SNC preparation for increasing the yield and collecting products with small size and high RC.


Assuntos
Nanopartículas , Amido , Amido/química , Hidrólise , Tamanho da Partícula , Ácidos , Nanopartículas/química , Amilopectina
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