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1.
BMC Geriatr ; 24(1): 426, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741042

RESUMO

OBJECTIVE: To examine the bi-directorial association between diversified leisure activity participation and cognitive function over a 7-year period. METHODS: Data analyzed was from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a large-scale longitudinal national study. The baseline survey was conducted in 2011 with follow-up every three years. We traced a total of 2718 participants over a period of 7 years. We used adjusted random intercept cross-lagged panel models (RI-CLPMs) to examine the bi-directorial associations between diversified leisure activity participation and cognitive function. RESULTS: We observed bi-directorial associations between diversity of leisure activity and cognitive function across waves at the between-person and within-person levels. The adjusted random intercept cross-lagged panel models fitted the data appropriately, and the 3-year cross-lagged effects of prior diversified leisure activity participation on cognitive function (ß = 0.058, p < 0.01) and cognitive function on subsequent diversified leisure activity participation (ß = 0.047, p < 0.05) were significant. The results remained after adjusting the model for baseline sex, age, educational level, marital status and current residence, the number of chronic diseases, ADL, depressive symptoms, sleep quality, smoking, and drinking. CONCLUSION: This study suggests that a reciprocal causality relationship between diversified leisure activity participation and cognitive function, indicating a "positive circle" that further promotes cognition over time.


Assuntos
Cognição , Atividades de Lazer , Humanos , Atividades de Lazer/psicologia , Masculino , Feminino , China/epidemiologia , Idoso , Cognição/fisiologia , Estudos Longitudinais , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade
2.
Mol Biol Rep ; 51(1): 650, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734811

RESUMO

BACKGROUND: Vitiligo is a common autoimmune skin disease. Capsaicin has been found to exert a positive effect on vitiligo treatment, and mesenchymal stem cells (MSCs) are also confirmed to be an ideal cell type. This study aimed to explore the influence of capsaicin combined with stem cells on the treatment of vitiligo and to confirm the molecular mechanism of capsaicin combined with stem cells in treating vitiligo. METHODS AND RESULTS: PIG3V cell proliferation and apoptosis were detected using CCK-8 and TUNEL assays, MitoSOX Red fluorescence staining was used to measure the mitochondrial ROS level, and JC-1 staining was used to detect the mitochondrial membrane potential. The expression of related genes and proteins was detected using RT‒qPCR and Western blotting. Coimmunoprecipitation was used to analyze the protein interactions between HSP70 and TLR4 or between TLR4 and mTOR. The results showed higher expression of HSP70 in PIG3V cells than in PIG1 cells. The overexpression of HSP70 reduced the proliferation of PIG3V cells, promoted apoptosis, and aggravated mitochondrial dysfunction and autophagy abnormalities. The expression of HSP70 could be inhibited by capsaicin combined with MSCs, which increased the levels of Tyr, Tyrp1 and DCT, promoted the proliferation of PIG3V cells, inhibited apoptosis, activated autophagy, and improved mitochondrial dysfunction. In addition, capsaicin combined with MSCs regulated the expression of TLR4 through HSP70 and subsequently affected the mTOR/FAK signaling pathway CONCLUSIONS: Capsaicin combined with MSCs inhibits TLR4 through HSP70, and the mTOR/FAK signaling pathway is inhibited to alleviate mitochondrial dysfunction and autophagy abnormalities in PIG3V cells.


Assuntos
Apoptose , Capsaicina , Proliferação de Células , Proteínas de Choque Térmico HSP70 , Melanócitos , Mitocôndrias , Transdução de Sinais , Serina-Treonina Quinases TOR , Receptor 4 Toll-Like , Vitiligo , Receptor 4 Toll-Like/metabolismo , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP70/genética , Serina-Treonina Quinases TOR/metabolismo , Vitiligo/metabolismo , Vitiligo/tratamento farmacológico , Capsaicina/farmacologia , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/efeitos dos fármacos , Linhagem Celular , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Autofagia/efeitos dos fármacos
3.
Heliyon ; 10(4): e25568, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420407

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a highly heterogeneous cancer. This heterogeneity has an impact on the efficacy of immunotherapy. Long noncoding RNAs (lncRNAs) have been found to play regulatory functions in cancer immunity. However, the global landscape of immune-derived lncRNA signatures has not yet been explored in colorectal cancer. METHODS: In this study, we applied DESeq2 to identify differentially expressed lncRNAs in colon cancer. Next, we performed an integrative analysis to globally identify immune-driven lncRNA markers in CRC, including immune-associated pathways, tumor immunogenomic features, tumor-infiltrating immune cells, immune checkpoints, microsatellite instability (MSI) and tumor mutation burden (TMB). RESULTS: We also identified dysregulated lncRNAs, such as LINC01354 and LINC02257, and their clinical relevance in CRC. Our findings revealed that the differentially expressed lncRNAs were closely associated with immune pathways. In addition, we found that RP11-354P11.3 and RP11-545G3.1 had the highest association with the immunogenomic signature. As a result, these signatures could serve as markers to assess immunogenomic activity in CRC. Among the immune cells, resting mast cells and M0 macrophages had the highest association with lncRNAs in CRC. The AC006129.2 gene was significantly associated with several immune checkpoints, for example, programmed cell death protein 1 (PD-1) and B and T lymphocyte attenuator (BTLA). Therefore, the AC006129.2 gene could be targeted to regulate the condition of immune cells or immune checkpoints to enhance the efficacy of immunotherapy in CRC patients. Finally, we identified 15 immune-related lncRNA-generated open reading frames (ORFs) corresponding to 15 cancer immune epitopes. CONCLUSION: In conclusion, we provided a genome-wide immune-driven lncRNA signature for CRC that might provide new insights into clinical applications and immunotherapy.

4.
Environ Sci Process Impacts ; 25(12): 1937-1944, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37786335

RESUMO

The formation and sedimentation of oil-mineral aggregates (OMAs) is the major method to transport spilled oil to the seafloor. In this study, the formation and sedimentation experiments of OMA using montmorillonite and four crude oils were performed in a wave tank in the presence of chemical dispersant. Most of the formed OMAs were droplet OMAs, and single droplet OMA would aggregate into multiple ones under the action of the dispersant. The size of the oil droplets trapped in the OMA increased with time and was larger for the oil with higher viscosity. The sinking velocities of OMAs formed in this study were between 100-1200 µm s-1 and they were positively correlated with their diameter. The density of OMA was of the same order as that of the crude oil that formed them. An increase in the dispersant dosage could promote the formation of OMAs. The oil content in OMAs was higher for the denser oil in the presence of a dispersant. The maximum oil trapping efficiency of OMAs was 48.05%. This study provides fundamental data on the formation kinetics of OMAs.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Óleo Mineral , Sedimentos Geológicos/química , Poluição por Petróleo/análise , Bentonita/química
5.
Orthop Surg ; 15(11): 2794-2804, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37667965

RESUMO

OBJECTIVE: To design appropriate orthosis for hallux valgus, a difficult foot condition that affects a quarter of the body's bones, we need to clarify the numerical biomechanical features, which have not been established in previous biomechanical studies. Therefore, we constructed a finite element model of the bunion foot to investigate the orthopaedic force compensation mechanism. METHODS: A patient with moderate hallux valgus was recruited. CT imaging data in DICOM format were extracted for three-dimensional foot model reconstruction. In conjunction with the need for rapid design of bunion orthosis, a metatarsal force application sizing method based on an orthogonal test design was investigated. The orthogonal test design was used to obtain the hallux valgus angle (HVA) and the inter metatarsal angle (IMA) data for different force combinations. Based on the extreme difference analysis and analysis of variance of the test results, the influence of different force combinations on the bunion angle was quickly determined. RESULTS: The results showed that the stress concentration occurred mainly in the first metatarsal bone. The distribution trend was in the medial and lateral middle of the bone and gradually decreased to the dorsal base of the bone body. The greatest stress occurs in the cartilage between the phalanges and metatarsals. In 25 groups of simulation experiments, HVA was reduced from 27.7° to 13°, and IMA was reduced from 12.5° to 7.3°. CONCLUSION: Applying detailed orthopaedic force collocation to the first metatarsal column can effectively restore the mechanics and kinematics of hallux valgus, and provide a reference for the treatment of bunion valgus and the design of orthopaedic devices.


Assuntos
Joanete , Hallux Valgus , Humanos , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/cirurgia , Análise de Elementos Finitos , Osteotomia/métodos , Aparelhos Ortopédicos , Resultado do Tratamento
6.
Br J Cancer ; 129(5): 884-894, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37474721

RESUMO

BACKGROUND: It is imperative to develop novel therapeutics to overcome chemoresistance, a significant obstacle in the clinical management of prostate cancer (PCa) and other cancers. METHODS: A phenotypic screen was performed to identify novel inhibitors of chemoresistant PCa cells. The mechanism of action of potential candidate(s) was investigated using in silico docking, and molecular and cellular assays in chemoresistant PCa cells. The in vivo efficacy was evaluated in mouse xenograft models of chemoresistant PCa. RESULTS: Nicardipine exhibited high selectivity and potency against chemoresistant PCa cells via inducing apoptosis and cell cycle arrest. Computational, molecular, and cellular studies identified nicardipine as a putative inhibitor of embryonic ectoderm development (EED) protein, and the results are consistent with a proposed mechanism of action that nicardipine destabilised enhancer of zeste homologue 2 (EZH2) and inhibited key components of noncanonical EZH2 signalling, including transducer and activator of transcription 3, S-phase kinase-associated protein 2, ATP binding cassette B1, and survivin. As a monotherapy, nicardipine effectively inhibited the skeletal growth of chemoresistant C4-2B-TaxR tumours. As a combination regimen, nicardipine synergistically enhanced the in vivo efficacy of docetaxel against C4-2 xenografts. CONCLUSION: Our findings provided the first preclinical evidence supporting nicardipine as a novel EED inhibitor that has the potential to be promptly tested in PCa patients to overcome chemoresistance and improve clinical outcomes.


Assuntos
Nicardipino , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Apoptose , Linhagem Celular Tumoral , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Nicardipino/farmacologia , Nicardipino/uso terapêutico , Complexo Repressor Polycomb 2 , Neoplasias da Próstata/tratamento farmacológico
7.
Cancer Med ; 12(15): 16076-16086, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37341068

RESUMO

BACKGROUND: Systemic chemotherapy or chemoradiation therapy has proven to be effective in treating advanced biliary tract carcinoma (BTC). However, its efficacy in the adjuvant setting remains controversial. Therefore, this study aimed to determine the prognostic significance of genomic biomarkers in resected BTC and their potential role in stratifying patients for adjuvant treatment. METHODS: We retrospectively reviewed 113 BTC patients who underwent curative-intent surgery and had available tumor sequencing data. Disease-free survival (DFS) was the primary outcome examined and univariate analysis was used to identify gene mutations with prognostic value. Favorable and unfavoratble gene subsets were distinguished from the selected genes through grouping, respectively. Multivariate Cox regression was used to identify independent prognostic factors of DFS. RESULTS: Our results indicated that mutations in ACVR1B, AR, CTNNB1, ERBB3, and LRP2 were favorable mutations, while mutations in ARID1A, CDKN2A, FGFR2, NF1, NF2, PBRM1, PIK3CA, and TGFBR1 were unfavorable mutations. In addition to age, sex, and node positive, favorable genes (HR = 0.15, 95% CI = 0.04-0.48, p = 0.001) and unfavorable genes (HR = 2.86, 95% CI = 1.51-5.29, p = 0.001) were identified as independent prognostic factors for DFS. Out of the 113 patients, only 35 received adjuvant treatment whereas the majority (78) did not. For patients with both favorable and unfavorable mutations undetected, adjuvant treatment showed negative effect on DFS (median DFS: S441 vs. 956 days, p = 0.010), but there was no significant difference in DFS among those in other mutational subgroups. CONCLUSIONS: Genomic testing might be useful in guiding the decisions regarding adjuvant treatment in BTC.


Assuntos
Neoplasias dos Ductos Biliares , Sistema Biliar , Carcinoma , Humanos , Estudos Retrospectivos , Prognóstico , Neoplasias dos Ductos Biliares/patologia , Mutação , Quimioterapia Adjuvante , Adjuvantes Imunológicos , Sistema Biliar/patologia
8.
Br J Pharmacol ; 180(13): 1730-1747, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36702458

RESUMO

BACKGROUND AND PURPOSE: Chemotherapy-induced neuropathic pain (CINP) currently has limited effective treatment. Although the roles of oxytocin (OXT) and the oxytocin receptor (OXTR) in central analgesia have been well documented, the expression and function of OXTR in the peripheral nervous system remain unclear. Here, we evaluated the peripheral antinociceptive profiles of OXTR in CINP. EXPERIMENTAL APPROACH: Paclitaxel (PTX) was used to establish CINP. Quantitative real-time polymerase chain reaction (qRT-PCR), in situ hybridization, and immunohistochemistry were used to observe OXTR expression in dorsal root ganglia (DRG). The antinociceptive effects of OXT were assessed by hot-plate and von Frey tests. Whole-cell patch clamp was performed to record sodium currents, excitability of DRG neurons, and excitatory synapse transmission. KEY RESULTS: Expression of OXTR in DRG neurons was enhanced significantly after PTX treatment. Activation of OXTR exhibited antinociceptive effects, by decreasing the hyperexcitability of DRG neurons in PTX-treated mice. Additionally, OXTR activation up-regulated the phosphorylation of protein kinase C (pPKC) and, in turn, impaired voltage-gated sodium currents, particularly the voltage-gated sodium channel 1.7 (NaV 1.7) current, that plays an indispensable role in PTX-induced neuropathic pain. OXT suppressed excitatory transmission in the spinal dorsal horn as well as excitatory inputs from primary afferents in PTX-treated mice. CONCLUSION AND IMPLICATIONS: The OXTR in small-sized DRG neurons is up-regulated in CINP and its activation relieved CINP by inhibiting the neural excitability by impairment of NaV 1.7 currents via pPKC. Our results suggest that OXTR on peripheral sensory neurons is a potential therapeutic target to relieve CINP.


Assuntos
Analgesia , Antineoplásicos , Neuralgia , Ratos , Camundongos , Animais , Receptores de Ocitocina/metabolismo , Regulação para Cima , Ratos Sprague-Dawley , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Células Receptoras Sensoriais/metabolismo , Gânglios Espinais/metabolismo , Ocitocina/farmacologia , Paclitaxel/farmacologia , Sódio/metabolismo , Antineoplásicos/farmacologia , Analgésicos/farmacologia , Analgésicos/metabolismo
9.
Environ Microbiol ; 24(11): 5139-5150, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35880613

RESUMO

Methylarsenite [MAs(III)] is a highly toxic arsenical produced by some microbes as an antibiotic. In this study, we demonstrate that a PadR family transcriptional regulator, PadRars , from Azospirillum halopraeferens strain Au 4 directly binds to the promoter region of the arsenic resistance (ars) operon (consisting of padRars , arsV, and arsW) and represses transcription of arsV and arsW genes involved in MAs(III) resistance. Quantitative reverse transcriptase PCR and transcriptional reporter assays showed that transcription of the ars operon is induced strongly by MAs(III) and less strongly by arsenite and antimonite. Electrophoretic mobility shift assays with recombinant PadRars showed that it represses transcription of the ars operon by binding to two inverted-repeat sequences within the ars promoter. PadRars has two conserved cysteine pairs, Cys56/57 and Cys133/134; mutation of the first pair to serine abolished the transcriptional response of the ars operon to trivalent metalloids, suggesting that Cys56/57 form a binding site for trivalent metalloids. Either C133S or C134S derivative responses to MAs(III) but not As(III) or Sb(III), suggesting that it is a third ligand to trivalent metalloids. PadRars represents a new type of repressor proteins regulating transcription of an ars operon involved in the resistance to trivalent metalloids, especially MAs(III).


Assuntos
Arsênio , Metaloides , Regulação Bacteriana da Expressão Gênica , Metaloides/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Óperon , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arsênio/metabolismo
10.
Environ Microbiol ; 24(2): 772-783, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35049138

RESUMO

Microbial arsenic methylation by arsenite (As(III)) S-adenosylmethionine methyltransferases (ArsMs) can produce the intermediate methylarsenite (MAs(III)), which is highly toxic and is used by some microbes as an antibiotic. Other microbes have evolved mechanisms to detoxify MAs(III). In this study, an arsRM operon was identified in the genome of an MAs(III)-methylation strain Noviherbaspirillum denitrificans HC18. The arsM gene (NdarsM) is located downstream of an open reading frame encoding an MAs(III)-responsive transcriptional regulator (NdArsR). The N. denitrificans arsRM genes are co-transcribed whose expression is significantly induced by MAs(III), likely by alleviating the repressive effect of ArsR on arsRM transcription. Both in vivo and in vitro assays showed that NdArsM methylates MAs(III) to dimethyl- and trimethyl-arsenicals but does not methylate As(III). Heterologous expression of NdarsM in arsenic-sensitive Escherichia coli AW3110 conferred resistance to MAs(III) but not As(III). NdArsM has the four conserved cysteine residues present in most ArsMs, but only two of them are essential for MAs(III) methylation. The ability to methylate MAs(III) by enzymes such as NdArsM may be an evolutionary step originated from enzymes capable of methylating As(III). This finding reveals a mechanism employed by microbes such as N. denitrificans HC18 to detoxify MAs(III) by further methylation.


Assuntos
Arsênio , Arsenicais , Oxalobacteraceae , Arsênio/metabolismo , Arsenicais/metabolismo , Metiltransferases/metabolismo , Óperon , Oxalobacteraceae/genética
11.
Molecules ; 26(24)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34946521

RESUMO

An increasing number of studies have demonstrated the antiviral nature of polyphenols, and many polyphenols have been proposed to inhibit SARS-CoV or SARS-CoV-2. Our previous study revealed the inhibitory mechanisms of polyphenols against DNA polymerase α and HIV reverse transcriptase to show that polyphenols can block DNA elongation by competing with the incoming NTPs. Here we applied computational approaches to examine if some polyphenols can also inhibit RNA polymerase (RdRp) in SARS-CoV-2, and we identified some better candidates than remdesivir, the FDA-approved drug against RdRp, in terms of estimated binding affinities. The proposed compounds will be further examined to develop new treatments for COVID-19.


Assuntos
Antivirais/farmacologia , Polifenóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Antocianinas/química , Antocianinas/farmacologia , Antivirais/isolamento & purificação , Simulação de Dinâmica Molecular , Estrutura Molecular , Polifenóis/química , RNA Polimerase Dependente de RNA , SARS-CoV-2/enzimologia , Tratamento Farmacológico da COVID-19
12.
Epileptic Disord ; 23(6): 823-832, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34609285

RESUMO

Temporal lobe epilepsy (TLE) in children is one of the most common refractory epilepsies. MicroRNAs (miRNAs) show abnormal expression in neurological disorders. The objective of this study was to determine changes in expression and the role of miR-29a in children with TLE. Sixty-five TLE patients and 70 normal controls were recruited. The levels of miR-29a were quantified using qRT-PCR. An in vitro TLE cell model was established using primary hippocampal cells cultured in magnesium-free medium. Cell viability, cell apoptosis and inflammatory cytokine concentrations were evaluated. The luciferase reporter assay was applied to confirm the target gene, HMGB1. A low level of MiR-29a expression was observed in the serum of children with TLE, which demonstrated a negative association with the concentration of serum TNF-α, IL-6, and IFN-γ. The level of MiR-29a demonstrated high specificity and sensitivity in children with TLE. A low level of expression of miR-29a was also detected in the TLE cell model. MiR-29a over-expression reversed the decreased cell viability induced by TLE, and alleviated cell apoptosis. Release of TNF-α, IL-6, and IFN-γ induced by TLE was also inhibited by miR-29a over-expression. HMGB1, which was downregulated in the serum of TLE patients, was shown to be a target gene of miR-29a, and negatively correlated with miR-29a level. The downregulation of serum miR-29a may serve as a non-invasive diagnostic biomarker for children with TLE. MiR-29a may be involved in the pathogenesis of TLE through regulation of neuronal apoptosis and neuroinflammation via targeting HMGB1.


Assuntos
Epilepsia do Lobo Temporal , Biomarcadores , Morte Celular , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/genética , Proteína HMGB1/genética , Hipocampo , Humanos , Interleucina-6 , MicroRNAs/genética , Doenças Neuroinflamatórias , Neurônios , Convulsões , Fator de Necrose Tumoral alfa
13.
Comput Struct Biotechnol J ; 19: 5371-5380, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567475

RESUMO

Although scientists around the world have put lots of effort into the development of new treatments for COVID-19 since the outbreak, no drugs except Veklury (remdesivir) have been approved by FDA. There is an urgent need to discover some alternative antiviral treatment for COVID-19. Because polyphenols have been shown to possess antiviral activities, here we conducted a large-scale virtual screening for more than 400 polyphenols. Several lead compounds such as Petunidin 3-O-(6″-p-coumaroyl-glucoside) were identified to have promising binding affinities and convincing binding mechanisms. Analyzing the docking results and ADME properties sheds light on the potential efficacy of the top-ranked drug candidates and pinpoints the key residues on the target proteins for the future of drug development.

14.
J Food Biochem ; : e13841, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34189729

RESUMO

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to analyze the polymerization distribution of xylo-oligosaccharides from birchwood and beechwood xylans following hydrolysis by the xylanase (XynA) from Bacillus subtilis, which was obtained by recombinant expression and purified by Ni2+ affinity column chromatography. The hydrolysis products of birchwood and beechwood xylans were analyzed by thin layer chromatography (TLC) and MALDI-TOF-MS. In the birchwood hydrolysate, the main neutral xylo-oligosaccharides were xylobiose (X2 ) and xylotriose (X3 ), and the acidic xylo-oligosaccharides (polymerization degree 4-12) were attached via a single methyl-glucuronic acid sidechain (MeG). Both X2 and X3 were identified in the beechwood xylan hydrolysate and acidic xylo-oligosaccharides (polymerization degree 4-16), which were structurally similar to those in the birchwood xylan hydrolysate. Therefore, the recombinant xylanase, XynA, has the potential to produce xylobiose (X2 ) and xylotriose (X3 ) as well as acidic xylo-oligosaccharides (MeGXn ) that would be applied in food industry. PRACTICAL APPLICATIONS: Xylo-oligosaccharides are a novel functional food additive, which has great potential in improving the quality of food. Xylo-oligosaccharides with methyl-glucuronic acid sidechains (MeG) are acidic xylo-oligosaccharides (MeGXn), which can be applied in the preparation of drugs for the treatment of cystitis and mucopolysaccharidosis. In this study, xylanase XynA was first obtained by gene cloning and expression and then used to hydrolyze the birchwood and beechwood xylans. The polymerization distribution of xylo-oligosaccharides generated during the enzymatic digestion was then determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Through enzyme hydrolysis, we are able to produce xylobiose and xylotriose for food additives.

15.
J Colloid Interface Sci ; 583: 234-242, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002695

RESUMO

Heating treatment is widely used in the preparation of metallic materials with controlled phase behavior and mechanical properties. However, for the soft materials assembled by short peptides, especially simple dipeptides, the detailed influences of heating treatment on the structures and functions of the materials remain largely unexplored. Here we showed that by thermal annealing or quenching of aromatic peptide solutions under kinetic control, we are able to control the self-assembly of peptide into materials with distinct phase behavior and macroscopic properties. The thermal annealing of the heated peptide solutions will lead to the formation of large nanobelts or bundles in solution, and no gels will be formed. However, by quenching the heated peptide solution, a self-supporting hydrogel will be formed quickly. Structure analysis revealed that the peptides preferred to self-assembled into much thinner and flexible nanohelices during quenching treatment. Moreover, the stability of the gels further increased with the repeated heating and quenching cycling of the peptide solutions. The results demonstrated that the heat treatment can be used to control the structure and function of self-assembled materials in a way similar to that of the conventional metallic or alloy materials.


Assuntos
Calefação , Hidrogéis , Dipeptídeos , Peptídeos
16.
J Colloid Interface Sci ; 578: 218-228, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531552

RESUMO

In this work, we report a strategy to self-assemble multifunctional hydrogels composed of highly ordered polyoxometalates (POMs) helical arrays using a liquid crystalline tripeptide as the template. The cationic peptide can self-assemble into long-range ordered nanofilaments with a diameter of ~4.1 nm in aqueous media. Through the incorporation of various multivalent polyoxometalates (POMs), the POMs clusters can spontaneously organize into periodic nanowire arrays by the colloidal co-assembly with the as-prepared nematic peptide nanofilaments. This leads to the formation of hybrid gels with tunable mechanical strength by simply changing the charge number of the POMs. The H3PW12O40 (noted as PW) clusters@peptide hybrid hydrogels show excellent adsorption performance of dyes. Moreover, the long-range aligned PW clusters within the co-assembled fiber bundles exhibit great improvement in the efficiency of photodegradation of dyes, which shows 8.7 times higher than that of the pristine PW clusters in the homogeneous phase. The synergistic effect between the adsorption and catalytic process within the hybrid gels is considered to be responsible for its highly catalytic activity. This work highlights a general pathway upon the well-defined organization of the various components into hybrid materials with superior properties using simple peptide liquid crystals as templates.


Assuntos
Cristais Líquidos , Compostos de Tungstênio , Hidrogéis , Peptídeos
17.
Pathol Res Pract ; 216(3): 152829, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32008865

RESUMO

Human leukocyte antigens (HLA) are heterodimeric cell surface molecules that bind short peptides derived from non-self and self proteins. Accumulative evidence showed that specific alleles of HLA class II were associated with the susceptibility to malignant tumors including acute leukemia. In this study, we investigated the association between four single nucleotide polymorphisms (SNPs) at HLA-DP/DQ and acute myeloid leukemia (AML) risk. We genotyped four SNPs in HLA-DP (rs3077 G > A and rs9277535 G > A) and HLA-DQ (rs2856718 A > G and rs7453920 G > A) in a case-control study of 545 AML cases and 1034 cancer-free controls using Taqman allelic discrimination assay. The associations between these SNPs and AML risk were estimated by computing the odds ratios (ORs) and their 95% confidence intervals (CIs) from multivariate logistic regression analysis. We found significant associations of the variant alleles in HLA-DP (rs3077 and rs9277535) and HLA-DQ rs7453920 with increased AML risk (adjusted OR = 1.29, 95%CI = 1.10-1.51for rs3077 in additive model; adjusted OR = 1.29, 95%CI = 1.11-1.51 for rs9277535 in additive model; adjusted OR = 3.18, 95%CI = 1.86-5.46 for rs7453920 in recessive model). When combining the effects of rs3077, rs9277535 and rs7453920, we found that AML risk was significantly increased with the increasing number of variant alleles of the three SNPs in a dose-dependent manner (P for trend < 0.001). Besides, we found multiplicative interaction between rs3077 and age (≤45 years old and > 45 years old; P = 0.046). In conclusion, HLA-DP and HLA-DQ loci are candidate susceptibility regions for AML in Han Chinese.


Assuntos
Predisposição Genética para Doença/genética , Antígenos HLA-DP/genética , Antígenos HLA-DQ/genética , Leucemia Mieloide Aguda/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
18.
Aging (Albany NY) ; 12(3): 2992-3009, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040445

RESUMO

Human placental mesenchymal stem cells (hPMSCs) have the ability to release cytokines and to differentiate into the three germ layers. To date, the relevance of hPMSCs for the treatment of premature ovarian insufficiency (POI) disease through the regulation of oxidative stress is still unclear. Therefore, to evaluate the therapeutic efficiency and investigate the mechanism of hPMSCs, we generated a mouse model of POI and collected human ovarian granule cells (hGCs) from patients with POI. hPMSCs displayed therapeutic effects on POI ovarian function, including recovered follicular numbers and increased expression of oocyte markers. Furthermore, secretion of the cytokine EGF (epidermal growth factor) was higher from hPMSCs than it was from other cells. FACS and Western blot analyses showed that EGF elevated the proliferation and reduced the apoptosis in hGCs. hPMSCs and EGF inhibited oxidative stress levels. Protein assays demonstrated that EGF suppressed oxidative stress by dose-dependently upregulating the expression of the NRF2/HO-1 pathway, and it inhibited the apoptosis by regulating the PTEN/PI3K/AKT pathway. These findings provide an experimental foundation for hPMSCs in improving ovarian function through the secretion of EGF. The mechanism of action of EGF is related to protection from oxidative stress by activation of the NRF2/HO-1.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Heme Oxigenase-1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Placenta/citologia , Insuficiência Ovariana Primária/metabolismo , Animais , Biomarcadores , Fator de Crescimento Epidérmico/genética , Feminino , Células da Granulosa/fisiologia , Heme Oxigenase-1/genética , Humanos , Transplante de Células-Tronco Mesenquimais , Camundongos , Fator 2 Relacionado a NF-E2/genética , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Gravidez , Insuficiência Ovariana Primária/genética , Espécies Reativas de Oxigênio , Regulação para Cima
19.
Cancer Med ; 8(14): 6476-6484, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31489978

RESUMO

PURPOSE: The overexpression and knockdown of PLK4 were both reported to generate aneuploidy. Thus, we aimed to investigate whether genetic variants in PLK4 contribute to the development of hepatocellular carcinoma (HCC). METHODS: We evaluated associations of common variants in PLK4 and its promoter for the risk of HCC in our association study (1300 cases and 1344 controls). The genotype-tissue expression (GTEx) and The cancer genome atlas (TCGA) databases were used to quantify the expression of PLK4. Cell proliferation and migration affected by PLK4 in HCC were assessed in vitro. Drug susceptibility testing (DST) model was used to assess the sensibility of PLK4-activated HCC to CFI-400945, a small molecule inhibitor of PLK4. RESULTS: Herein, we found a significant association between rs3811741, located in the PLK4 intron, and liver cancer risk (OR = 1.26, P = 9.81 × 10-5 ). Although PLK4 expressed at lower levels in somatic tissues compared to the testis, the risk allele A of rs3811741 was associated with increased PLK4 expression in liver cancer tissues. Additionally, PLK4 high expression was remarkably associated with shortened survival of HCC (HR = 1.97, P = .001). Furthermore, overexpression of PLK4 promoted, while knockdown of PLK4 suppressed cancer cell proliferation, migration, and invasion. DST model demonstrated that CFI-400945 can effectively suppress rampant proliferation of HCC with highly expressed PLK4. CONCLUSION: Taken together, our study demonstrated that PLK4 is a susceptibility gene and plays an oncogenic role in HCC. Furthermore, we identified that PLK4 sensitives HCC to CFI-400945, which may be an ideal therapy target for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Transformação Celular Neoplásica/genética , Predisposição Genética para Doença , Variação Genética , Neoplasias Hepáticas/genética , Proteínas Serina-Treonina Quinases/genética , Locos de Características Quantitativas , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Estudos de Associação Genética , Humanos , Íntrons , Neoplasias Hepáticas/patologia , Polimorfismo de Nucleotídeo Único
20.
Mol Genet Genomic Med ; 7(5): e633, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884202

RESUMO

BACKGROUND: Gastric cancer (GC), the second leading cause of cancer mortality behind lung cancer worldwide, is caused by both genetic and environmental factors. In this study, we evaluated the association between the genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR), methionine synthesis reductase (MTR), and methyltransferase reductase (MTRR) genes and ischemic stroke risk in Chinese population. METHODS: A case-control study was conducted including 681 patients with GC and 756 healthy controls. Chi-squared test/Fisher's exact test and genetic model were used to evaluate associations. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using unconditional logistic regression. RESULTS: In the allele model, using the chi-square test, we found that the rs1532268 in MTRR with a minor allele T was significantly associated with increased risk of GC (OR = 1.24, 95% CI, 1.00-1.53; p = 0.048). In the genetic model analysis, we identified that the single-nucleotide polymorphism of the rs1801133 in MTHFR could increase the GC risk in the recessive model (OR = 1.31, 95% CI, 1.01-1.70; p = 0.042) and log-additive model (OR = 1.19, 95% CI, 1.02-1.38; p = 0.025). In MTHFR, a strong linkage of rs2274976 and rs1801133 was detected. The haplotype "GC" in the MTHFR gene was found to prominently increase the risk of GC (OR = 1.26, 95% CI: 1.07-1.47; p = 0.005). Other haplotypes did not display the correlativity. CONCLUSION: This study suggested that MTR and MTHFR polymorphisms may contribute to increase the risk of GC.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Ferredoxina-NADP Redutase/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/genética , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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