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1.
BMC Genomics ; 25(1): 206, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395755

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with a five-year survival rate of approximately 10%. Genetic mutations are pivotal drivers in PDAC pathogenesis, but recent investigations also revealed the involvement of non-genetic alterations in the disease development. In this study, we undertook a multi-omics approach, encompassing ATAC-seq, RNA-seq, ChIP-seq, and Hi-C methodologies, to dissect gene expression alterations arising from changes in chromosome accessibility and chromatin three-dimensional interactions in PDAC. RESULTS: Our findings indicate that chromosomal structural alterations can lead to abnormal expressions on key genes during PDAC development. Notably, overexpression of oncogenes FGFR2, FOXA2, CYP2R1, and CPOX can be attributed to the augmentation of promoter accessibility, coupled with long-range interactions with distal elements. Additionally, our findings indicate that chromosomal structural alterations caused by genomic instability can lead to abnormal expressions in PDACs. As an example, by analyzing chromosomal changes, we identified a putative oncogenic gene, LPAR1, which shows upregulated expression in both PDAC cell lines and clinical samples. The overexpression is correlated with alterations in LPAR1-associated 3D genome structure and chromatin state. We further demonstrated that high LPAR1 activity is required for enhanced PDAC cell migration in vitro. CONCLUSIONS: Collectively, our findings reveal that the chromosomal conformational alterations, in addition to the well-known genetic mutations, are critical for PDAC tumorigenesis.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinogênese/genética , Expressão Gênica , Cromatina/genética , Regulação Neoplásica da Expressão Gênica
2.
NMR Biomed ; 37(5): e5098, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38224670

RESUMO

The overlapping peaks of the target chemical exchange saturation transfer (CEST) solutes and other unknown CEST solutes affect the quantification results and accuracy of the chemical exchange parameters-the fractional concentration, f b , exchange rate, k b , and transverse relaxation rate, R 2 b -for the target solutes. However, to date, no method has been established for assessing the overlapping peaks. This study aimed to develop a method for quantifying the f b , k b , and R 2 b values of a specific CEST solute, as well as assessing the overlap between the CEST peaks of the specific solute(s) and other unknown solutes. A simplified R 1 ρ model was proposed, assuming linear approximation of the other solutes' contributions to R 1 ρ . A CEST data acquisition scheme was applied with various saturation offsets and saturation powers. In addition to fitting the f b , k b , and R 2 b values of the specific solute, the overlapping condition was evaluated based on the root mean square error (RMSE) between the trajectories of the acquired and synthesized data. Single-solute and multi-solute phantoms with various phosphocreatine (PCr) concentrations and pH values were used to calculate the f b and k b of PCr and the corresponding RMSE. The feasibility of RMSE for evaluating the overlapping condition, and the accurate fitting of f b and k b in weak overlapping conditions, were verified. Furthermore, the method was employed to quantify the nuclear Overhauser effect signal in rat brains and the PCr signal in rat skeletal muscles, providing results that were consistent with those reported in previous studies. In summary, the proposed approach can be applied to evaluate the overlapping condition of CEST peaks and quantify the f b , k b , and R 2 b values of specific solutes, if the weak overlapping condition is satisfied.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética , Ratos , Animais , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas
3.
Artigo em Inglês | MEDLINE | ID: mdl-38323900

RESUMO

Three microaerophilic bacterial strains, designated SG22T, SG63T and SG29T were isolated from paddy soils in PR China. Cells of these strains were Gram-staining-negative and long rod-shaped. SG22T, SG63T and SG29T showed the highest 16S rRNA gene sequence similarities with the members of the genus Anaeromyxobacter. The results of phylogenetic and phylogenomic analysis also indicated that these strains clustered with members of the genus Anaeromyxobacter. The main respiratory menaquinone of SG22T, SG63T and SG29T was MK-8 and the major fatty acids were iso-C15 : 0, iso-C17 : 0 and C16 : 0. SG22T, SG29T and SG63T not only possessed iron reduction ability but also harboured genes (nifHDK) encoding nitrogenase. The genomic DNA G+C contents of SG22T, SG63T and SG29T ranged from 73.3 to 73.5 %. The average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values between SG22T, SG63T and SG29T and the closely related species of the genus Anaeromyxobacter were lower than the cut-off values (dDDH 70 % and ANI 95-96 %) for prokaryotic species delineation. On the basis of these results, strains SG22T, SG63T and SG29T represent three novel species within the genus Anaeromyxobacter, for which the names Anaeromyxobacter terrae sp. nov., Anaeromyxobacter oryzisoli sp. nov. and Anaeromyxobacter soli sp. nov., are proposed. The type strains are SG22T (= GDMCC 1.3185T = JCM 35581T), SG63T (= GDMCC 1.2914T = JCM 35124T) and SG29T (= GDMCC 1.2911T = JCM 35123T).


Assuntos
Myxococcales , Bactérias Fixadoras de Nitrogênio , Compostos Férricos , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Nucleotídeos , Solo
4.
Phys Chem Chem Phys ; 26(8): 6956-6966, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38334722

RESUMO

The investigation and development of high thermoelectric value materials has become a research hotspot in recent years. In this work, based on the density functional theory on the Perdew-Burke-Ernzerhof (GGA-PBE) level, the thermoelectric properties of transition metal halides CdBr, Janus Cd2BrI, and CdI monolayers have been systematically investigated using Boltzmann transport theory. The calculation of the electronic band structure shows that these three materials have indirect band gap semiconductor properties. For carrier transport, the electron mobilities for CdBr, Janus Cd2BrI, and CdI monolayers are found to be 74, 16, 21 cm2 s-1 V-1 for p-type doping and 116, 102, 78 cm2 s-1 V-1 for n-type doping. Regarding their phonon transport, the CdBr, Cd2BrI, and CdI monolayers all have very low lattice thermal conductivity (4.78, 2.46, and 1.65 W m-1 K-1, respectively) that decreases with increasing temperature, which is favorable for obtaining large zT values. The electrical transport results show that the performance of p-type doping is better than that of n-type doping. At 300 K, the Seebeck coefficients of p-type doping for the CdBr, Cd2BrI, and CdI monolayers are 217.72, 246.43, and 226.24 µV K-1, respectively. In addition, we predict that the zT values of the CdBr, Cd2BrI, and CdI monolayers are 0.62, 1.64, and 0.87 for p-type doping at 300 K respectively. The zT values increase with the increase of temperature. In particular, the Janus Cd2BrI monolayer has a zT value of 3.03 at 600 K. These results suggest that all these materials can be good candidates for thermoelectric materials.

5.
Neurobiol Dis ; 181: 106110, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37001614

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with progressive paralysis of limbs and bulb in patients, the cause of which remains unclear. Accumulating studies suggest that motor neuron degeneration is associated with systemic metabolic impairment in ALS. However, the metabolic reprogramming and underlying mechanism in the longitudinal progression of the disease remain poorly understood. In this study, we aimed to investigate the molecular changes at both metabolic and proteomic levels during disease progression to identify the most critical metabolic pathways and underlying mechanisms involved in ALS pathophysiological changes. Utilizing liquid chromatography-mass spectrometry-based metabolomics, we analyzed the metabolites' levels of plasma, lumbar spinal cord, and motor cortex from SOD1G93A mice and wildtype (WT) littermates at different stages. To elucidate the regulatory network underlying metabolic changes, we further analyzed the proteomics profile in the spinal cords of SOD1G93A and WT mice. A group of metabolites implicated in purine metabolism, methionine cycle, and glycolysis were found differentially expressed in ALS mice, and abnormal expressions of enzymes involved in these metabolic pathways were also confirmed. Notably, we first demonstrated that dysregulation of purine metabolism might contribute to the pathogenesis and disease progression of ALS. Furthermore, we discovered that fatty acid metabolism, TCA cycle, arginine and proline metabolism, and folate-mediated one­carbon metabolism were also significantly altered in this disease. The identified differential metabolites and proteins in our study could complement existing data on metabolic reprogramming in ALS, which might provide new insight into the pathological mechanisms and novel therapeutic targets of ALS.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Animais , Camundongos , Esclerose Lateral Amiotrófica/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Metabolômica , Camundongos Transgênicos , Neurônios Motores/patologia , Doenças Neurodegenerativas/metabolismo , Proteômica , Purinas , Medula Espinal/patologia , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
6.
Phys Chem Chem Phys ; 25(45): 31312-31325, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37955953

RESUMO

Two-dimensional (2D) materials have been one of the most popular objects in the research field of thermoelectric (TE) materials and have attracted substantial attention in recent years. Inspired by the synthesized 2H-MoSSe and numerous theoretical studies, we systematically investigated the electronic, thermal, and TE properties of Janus 2H-MXTe (M = Zr and Hf; X = S and Se) monolayers by using first-principles calculations. The phonon dispersion curves and AIMD simulations confirm the thermodynamic stabilities. Moreover, Janus 2H-MXTe were evaluated as indirect band-gap semiconductors with band gaps ranging from 0.56 to 0.90 eV using the HSE06 + SOC method. To evaluate the TE performance, firstly, we calculated the temperature-dependent carrier relaxation time with acoustic phonon scattering τac, impurity scattering τimp, and polarized scattering τpol. Secondly, the calculation of lattice thermal conductivity (κl) shows that these monolayers possess relatively poor κl with values of 3.4-5.4 W mK-1 at 300 K, which is caused by the low phonon lifetime and group velocity. After computing the electronic transport properties, we found that the n-type doped Janus 2H-MXTe monolayers exhibit a high Seebeck coefficient exceeding 200 µV K-1 at 300 K, resulting in a high TE power factor. Eventually, combining the electrical and thermal conductivities, the optimal dimensionless figure of merit (zT) at 300 K (900 K) can be obtained, which is 0.94 (3.63), 0.51 (2.57), 0.64 (2.72), and 0.50 (1.98) for n-type doping of ZrSeTe, HfSeTe, ZeSTe, and HfSTe monolayers. Particularly, the ZrSeTe monolayer shows the best TE performance with the maximal zT value. These results indicate the excellent application potential of Janus 2H-MXTe (M = Zr and Hf; X = S and Se) monolayers in TE materials.

7.
Bioorg Chem ; 141: 106867, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37734195

RESUMO

Cyclometalated iridium complexes with mitochondrial targeting show great potential as substitutes for platinum-based complexes because of their strong anti-cancer properties. Three novel cyclometalated iridium(III) compounds were synthesized and evaluated in five different cell lines as part of the ongoing systematic investigations of these compounds. The complexes were prepared using 4,7-dichloro-1,10-phenanthroline ligands. The cytotoxicity of complexes Ir1-Ir3 towards HeLa cells was shown to be high, with IC50 values of 0.83±0.06, 4.73±0.11, and 4.95±0.62 µM, respectively. Complex Ir1 could be ingested by HeLa cells in 3 h and has shown high selectivity toward mitochondria. Subsequent investigations demonstrated that Ir1 triggered apoptosis in HeLa cells by augmenting the generation of reactive oxygen species (ROS), reducing the mitochondrial membrane potential, and depleting ATP levels. Furthermore, the movement of cells was significantly suppressed and the progression of the cell cycle was arrested in the G0/G1 phase following the administration of Ir1. The Western blot analysis demonstrated that the induction of apoptosis in HeLa cells by Ir1 involves the activation of the mitochondria-dependent channel and the PI3K/AKT signaling pathway. No significant cytotoxicity was observed in zebrafish embryos at concentrations less than or equal to 16 µM, e.g., survival rate and developmental abnormalities. In vivo, antitumor assay demonstrated that Ir1 suppressed tumor growth in mice. Therefore, our work shows that complex Ir1 could be a promising candidate for developing novel antitumor drugs.


Assuntos
Antineoplásicos , Complexos de Coordenação , Humanos , Camundongos , Animais , Células HeLa , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , Irídio/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Complexos de Coordenação/farmacologia , Complexos de Coordenação/metabolismo , Peixe-Zebra/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Apoptose , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proliferação de Células
8.
BMC Med Ethics ; 24(1): 57, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37533018

RESUMO

BACKGROUND: An increasing number of studies on physicians' professionalism have been done since the 2002 publication of Medical Professionalism in the New Millennium: A Physician Charter. The Charter proposed three fundamental principles and ten responsibilities. However, most studies were done in developed countries, and few have been done in China. Additionally, few studies have examined the effect of patient-centered hospital culture (PCHC) on physicians' professionalism. We aimed to investigate physicians' medical professionalism in public hospitals in China, and to assess mediating effect of professional attitudes in the relationship of PCHC with professional behaviours. METHODS: Self-administered questionnaires including professional attitudes (20 items) and behaviours (10 items) survey and PCHC scale (22 items) were given to clinical physicians in five public hospitals, China. The mediating effect of professional attitudes in the relationship of PCHC with professional behaviours was tested. RESULT: 232 valid questionnaires were collected. More than 90% (208) respondents agreed with 15 of 20 specific statements on medical professionalism. As for the responsibility of improving quality of care, 54 (23%) respondents disagreed with reporting of incompetent colleagues and as for the responsibility of maintaining professional competence, 49 (21%) disagreed with recertification. More than 185 (83%) respondents reported that they sometimes, usually, or always showed the four positive behaviours on the questionnaire, and 173 (77%) reported that they never showed the six negative behaviours. Mediating effect analysis revealed that two dimensions of PCHC (i.e. value/institution culture and behaviour/material culture) had a significant positive impact on physicians' professional behaviour, and professional attitude played a complete mediation role between them, but another dimension of PCHC (i.e. negative evaluation of hospital) directly affected professional behaviour without influencing professional attitude. CONCLUSION: Chinese physicians showed positive professional attitudes and behaviours. Different dimensions of PCHC affected physicians' attitudes and behaviours in different ways.


Assuntos
Atitude do Pessoal de Saúde , Médicos , Humanos , Estudos Transversais , Inquéritos e Questionários , Hospitais Públicos , Assistência Centrada no Paciente
9.
BMC Surg ; 23(1): 133, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198675

RESUMO

BACKGROUND: Recent studies have shown that near-infrared (NIR) fluorescence imaging using Indocyanine green (ICG) may improve the efficiency of sentinel lymph node biopsy (SLNB). This study aimed to assess the effectiveness of the combination of ICG and methylene blue (MB) in breast cancer patients undergoing SLNB. PATIENTS AND METHOD: We evaluated ICG plus MB (ICG + MB) identification effectiveness with MB alone using retrospective analysis. From 2016 to 2020, we collected data on 300 eligible breast cancer patients who got SLNB treatment in our institution by ICG + MB or MB alone. By comparing the distribution of clinicopathological characteristics, the detection rate of sentinel lymph nodes (SLNs) and metastatic SLNs, as well as the total number of SLNs in the two groups, we were able to assess the imaging efficiency. RESULTS: Fluorescence imaging allowed 131 out of 136 patients in the ICG + MB group to find SLNs. ICG + MB group and MB group had detection rates of 98.5% and 91.5% (P = 0.007, χ2 = 7.352), respectively. Besides, the ICG + MB approach was able to produce improved recognition outcomes. What's more, compared with the MB group, the ICG + MB group can identify more lymph nodes (LNs) (3.1 to 2.6, P = 0.000, t = 4.447). Additionally, in the ICG + MB group, ICG could identify more LNs than MB (3.1 vs 2.6, P = 0.004, t = 2.884). CONCLUSION: ICG has high detection effectiveness for SLNs, and when paired with MB, the detection efficiency can be increased even further. Furthermore, the ICG + MB tracing mode does not involve radioisotopes, which has a lot of promise for clinical use and can take the place of conventional standard detection methods.


Assuntos
Neoplasias da Mama , Biópsia de Linfonodo Sentinela , Humanos , Feminino , Biópsia de Linfonodo Sentinela/métodos , Verde de Indocianina , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Estudos Retrospectivos , Azul de Metileno , Corantes
10.
Alzheimers Dement ; 19(6): 2365-2375, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36469008

RESUMO

We propose the hypothesis that the cerebellar electrophysiology and sleep-wake cycles may be altered at the early stage of Alzheimer's disease (AD), proceeding the amyloid-ß neuropathological hallmarks. The electrophysiologic characteristics of cerebellum thereby might be served as a biomarker in the prepathological detection of AD. Sleep disturbances are common in preclinical AD patients, and the cerebellum has been implicated in sleep-wake regulation by several pioneer studies. Additionally, recent studies suggest that the structure and function of the cerebellum may be altered at the early stages of AD, indicating that the cerebellum may be involved in the disease's progression. We used APPswe /PS1ΔE9 mice as a model of AD, monitored and analyzed electroencephalogram data, and assessed neuropathological profiles in the cerebellum of AD mice. Our hypothesis may establish a linkage between the cerebellum and AD, thereby potentially providing new perspectives on the pathogenesis of the disease.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Cerebelo/metabolismo , Modelos Animais de Doenças , Presenilina-1/genética , Presenilina-1/metabolismo
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(2): 140-146, 2023 Feb 15.
Artigo em Zh | MEDLINE | ID: mdl-36854689

RESUMO

OBJECTIVES: To study new biomarkers for the early diagnosis of retinopathy of prematurity (ROP) by analyzing the differences in blood metabolites based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and metabolomics. METHODS: Dried blood spots were collected from 21 infants with ROP (ROP group) and 21 infants without ROP (non-ROP group) who were hospitalized in the Sixth Affiliated Hospital of Sun Yat-sen University from January 2013 to December 2016. LC-MS/MS was used to measure the metabolites, and orthogonal partial least squares-discriminant analysis was used to search for differentially expressed metabolites and biomarkers. RESULTS: There was a significant difference in blood metabolic profiles between the ROP and non-ROP groups. The pattern recognition analysis, Score-plot, and weight analysis obtained 10 amino acids with a relatively large difference. Further statistical analysis showed that the ROP group had significant increases in blood levels of glutamic acid, leucine, aspartic acid, ornithine, and glycine compared with the non-ROP group (P<0.05). The receiver operating characteristic curve analysis showed that glutamic acid and ornithine had the highest value in diagnosing ROP. CONCLUSIONS: Blood metabolites in preterm infants with ROP are different from those without ROP. Glutamic acid and ornithine are the metabolic markers for diagnosing ROP. LC-MS/MS combined with metabolomics analysis has a potential application value in the early identification and diagnosis of ROP.


Assuntos
Retinopatia da Prematuridade , Espectrometria de Massas em Tandem , Recém-Nascido , Lactente , Humanos , Recém-Nascido Prematuro , Cromatografia Líquida , Retinopatia da Prematuridade/diagnóstico , Ácido Glutâmico , Ornitina
12.
Biomacromolecules ; 23(4): 1622-1632, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35104104

RESUMO

Antimicrobial materials are an urgent need for modern wound care in the clinic. Although traditional polyurethane foams have proven to be clinically valuable for wound treatment, their petroleum-originated preparation and bioinert nature have restricted their efficacy in biomedical applications. Here, we propose a simple one-step foaming method to prepare lignin-based polyurethane foams (LPUFs) in which fully biobased polyether polyols partially replace traditional petroleum-based raw materials. The trace amount of phenolic hydroxyl groups (about 4 mmol) in liquefied lignin acts as a direct reducing agent and capping agent to silver ions (less than 0.3 mmol), in situ forming silver nanoparticles (Ag NPs) within the LPUF skeleton. This newly proposed lignin polyurethane/Ag composite foam (named as Ag NP-LPUF) shows improved mechanical, thermal, and antibacterial properties. It is worth mentioning that the Ag NP-LPUF exhibits more than 99% antibacterial rate against Escherichia coli within 1 h and Staphylococcus aureus within 4 h. Evaluations in mice indicate that the antimicrobial composite foams can effectively promote wound healing of full-thickness skin defects. As a proof of concept, this antibacterial and biodegradable foam exhibits significant potential for clinical translation in wound care dressings.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Petróleo , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Escherichia coli , Lignina/farmacologia , Camundongos , Poliuretanos/farmacologia , Prata/farmacologia , Cicatrização
13.
Phys Chem Chem Phys ; 25(1): 274-285, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36475497

RESUMO

Janus transition metal dichalcogenide monolayers (TMDs) have attracted wide attention due to their unique physical and chemical properties since the successful synthesis of the MoSSe monolayer. However, the related studies of Janus monolayers of transition metal halides (TMHs) with similar structures have rarely been reported. In this article, we systematically investigate the electronic properties, piezoelectric properties, optical properties, and carrier mobility of new Janus TiXY (X ≠ Y, X/Y = Cl, Br, I) monolayers using first principles calculations for the first time. These Janus TiXY monolayers are thermally, dynamically, and mechanically stable, and their energy bands near the Fermi level (EF) are almost entirely contributed by the central Ti atom. Besides, the Janus TiXY monolayers exhibit excellent in-plane and out-of-plane piezoelectric effects, especially with an in-plane piezoelectric coefficient of ∼4.58 pm V-1 for the TiBrI monolayer and an out-of-plane piezoelectric coefficient of ∼1.63 pm V-1 for the TiClI monolayer, suggesting their promising applications in piezoelectric sensors and energy storage applications. The absorption spectra of Janus TiXY monolayers are mainly distributed in the visible and infrared regions, implying that they are fantastic candidates for photoelectric and photovoltaic applications. The obtained carrier mobilities revealed that TiXY monolayers are hole-type semiconductors. Under uniaxial compressive strain, the hole mobilities of these monolayers are gradually improved, indicating that TiXY monolayers have potential applications in the field of flexible electronic devices.

14.
Mar Drugs ; 20(2)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35200655

RESUMO

As an important enzyme involved in the marine carbon cycle, alginate lyase has received extensive attention because of its excellent degradation ability on brown algae, which is widely utilized for alginate oligosaccharide preparation or bioethanol production. In comparison with endo-type alginate lyases (PL-5, PL-7, and PL-18 families), limited studies have focused on PL-17 family alginate lyases, especially for those with special characteristics. In this study, a novel PL-17 family alginate lyase, Aly23, was identified and cloned from the marine bacterium Pseudoalteromonas carrageenovora ASY5. Aly23 exhibited maximum activity at 35 °C and retained 48.93% of its highest activity at 4 °C, representing an excellent cold-adaptation property. Comparative molecular dynamics analysis was implemented to explore the structural basis for the cold-adaptation property of Aly23. Aly23 had a high substrate preference for poly ß-D-mannuronate and exhibited both endolytic and exolytic activities; its hydrolysis reaction mainly produced monosaccharides, disaccharides, and trisaccharides. Furthermore, the enzymatic hydrolyzed oligosaccharides displayed good antioxidant activities to reduce ferric and scavenge radicals, such as hydroxyl, ABTS+, and DPPH. Our work demonstrated that Aly23 is a promising cold-adapted biocatalyst for the preparation of natural antioxidants from brown algae.


Assuntos
Antioxidantes/farmacologia , Oligossacarídeos/farmacologia , Polissacarídeo-Liases/metabolismo , Pseudoalteromonas/metabolismo , Antioxidantes/metabolismo , Dissacarídeos/metabolismo , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Hidrólise , Simulação de Dinâmica Molecular , Monossacarídeos/metabolismo , Oligossacarídeos/metabolismo , Polissacarídeo-Liases/isolamento & purificação , Temperatura , Trissacarídeos/metabolismo
15.
Mar Drugs ; 20(12)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36547930

RESUMO

κ-carrageenases are members of the glycoside hydrolase family 16 (GH16) that hydrolyze sulfated galactans in red algae, known as κ-carrageenans. In this study, a novel κ-carrageenase gene from the marine bacterium Rhodopirellula sallentina SM41 (RsCgk) was discovered via the genome mining approach. There are currently no reports on κ-carrageenase from the Rhodopirellula genus, and RsCgk shares a low identity (less than 65%) with κ- carrageenase from other genera. The RsCgk was heterologously overexpressed in Escherichia coli BL21 and characterized for its enzymatic properties. RsCgk exhibited maximum activity at pH 7.0 and 40 °C, and 50% of its initial activity was retained after incubating at 30 °C for 2 h. More than 70% of its activity was maintained after incubation at pH 6.0-8.0 and 4 °C for 24 h. As a marine derived enzyme, RsCgk showed excellent salt tolerance, retaining full activity in 1.2 M NaCl, and the addition of NaCl greatly enhanced its thermal stability. Mass spectrometry analysis of the RsCgk hydrolysis products revealed that the enzyme had high degradation specificity and mainly produced κ-carrageenan disaccharide. Comparative molecular dynamics simulations revealed that the conformational changes of tunnel-forming loops under salt environments may cause the deactivation or stabilization of RsCgk. Our results demonstrated that RsCgk could be utilized as a potential tool enzyme for efficient production of κ-carrageenan oligosaccharides under high salt conditions.


Assuntos
Tolerância ao Sal , Cloreto de Sódio , Carragenina/química , Bactérias/metabolismo , Glicosídeo Hidrolases/metabolismo , Proteínas de Bactérias/metabolismo
16.
Gen Physiol Biophys ; 41(1): 15-30, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35253647

RESUMO

Chronic pancreatitis (CP), a fibroinflammatory disease, is a potential risk factor for pancreatic cancer. This study attempted to identify and analyze the key genes involved in CP development and their association with pancreatic cancer. The GSE41418 dataset was obtained from the Gene Expression Omnibus database. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed on common differentially expressed genes. A protein-protein interaction network was constructed by using the STRING database. The expression and prognostic value of hub genes in pancreatic cancer were analyzed by Gene Expression Profiling Interactive Analysis (GEPIA) and UALCAN databases. The results showed that the upregulated genes primarily focused on the cell cycle, DNA replication, and phagosome activity. The PPI network was composed of 184 nodes and 925 edges. The 10 hub genes were screened by CytoHubba, of which CCNB2, CDC6, CDK1 and CKS2 were observed to be differentially expressed in pancreatic cancer with CP, and all of them were detrimental to overall survival and recurrence-free survival of pancreatic cancer. In this study, we employed bioinformatic analysis to determine that CCNB2, CDC6, CDK1 and CKS2 may be key genes in the development of CP and pancreatic cancer.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Neoplasias Pancreáticas , Pancreatite Crônica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Quinases relacionadas a CDC2 e CDC28/genética , Quinases relacionadas a CDC2 e CDC28/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Biologia Computacional/métodos , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Humanos , Neoplasias Pancreáticas/genética , Pancreatite Crônica/genética
17.
J Gastroenterol Hepatol ; 36(9): 2601-2609, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33656759

RESUMO

BACKGROUND AND AIM: Programmed cell death-ligand 1 (PD-L1) immunohistochemistry score has been approved as the predictive biomarker for anti-PD1/PD-L1 therapy in several advanced malignancies. Although its predictive role remained inconclusive in hepatocellular carcinoma, ongoing study of anti-PD1/PD-L1 therapy showed promising results. However, less is known about the PD-L1 immunohistochemistry score and factors correlated with it in hepatocellular carcinoma. We investigated PD-L1 immunohistochemistry scores in a large cohort of hepatocellular carcinoma, as well as its correlation with various clinical and genomic factors. METHODS: Immunohistochemistry was performed to detect the expression of PD-L1 protein in 315 hepatocellular carcinoma tissues. All slides were independently reviewed by three senior pathologists. Next-generation YS panel (450 genes) sequencing was performed on 309 patients. RESULTS: Higher PD-L1 expression as measured by combined positive score (CPS) was associated with increased Edmondson-Steiner grade (grade III vs II, P = 0.041) and TP53 mutations (P = 0.021). PD-L1 CPS had no correlation with tumor mutational burden (Spearman's correlation coefficient 0.067). PD-L1 CPS was not significantly associated with hepatitis B virus infection. CONCLUSIONS: Our data indicated that patients with higher Edmondson-Steiner grade (grade III) had significantly higher PD-L1 CPS than patients with lower Edmondson-Steiner grade (grade II). Patients with TP53 mutations had significantly higher PD-L1 expression.


Assuntos
Antígeno B7-H1 , Carcinoma Hepatocelular , Neoplasias Hepáticas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Antígeno B7-H1/biossíntese , Antígeno B7-H1/genética , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Imunoquímica , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Adulto Jovem
18.
Support Care Cancer ; 29(9): 5009-5019, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33587173

RESUMO

PURPOSE: To explore the incidence, severity, and risk factors of multidimensional fatigue in patients with nasopharyngeal carcinoma (NPC) receiving concurrent chemoradiotherapy (CCRT). METHODS: This prospective study included 79 patients with NPC in Guangzhou (China) from June 2015 to July 2018. Data were collected before and after CCRT, including demographic and clinical characteristics, nutritional parameters, and fatigue scores, based on completion of the Multiple Dimensional Inventory-20 Questionnaire, with five subscales: General Fatigue, Mental Fatigue, Physical Fatigue, Reduced Activity, and Reduced Motivation. RESULTS: Increased general fatigue was found to be associated with lower lymphocyte count and body mass index <23 kg/m2. Increased physical fatigue was related to age > 42 years. Higher scores for reduced activity were associated with age > 42 years, female sex, and lower serum sodium. Increased mental fatigue was related with lower lymphocyte count and unemployment; and increased total fatigue was associated with lower lymphocyte count, age > 42 years, and 3-6 courses of treatment. Furthermore, 3-6 courses of treatment was an independent predictor of severe general fatigue, while age >42 years was an independent predictor of severe physical fatigue. Importantly, cancer stage IVB and 3-6 courses of treatment could predict severe total fatigue. CONCLUSIONS: Our data demonstrate that fatigue is increased in all dimensions in NPC patients following CCRT, and that the predictors differ for each fatigue dimension. These results could guide the development of targeted interventions that may reduce the impact of cancer-related fatigue in patients with NPC.


Assuntos
Neoplasias Nasofaríngeas , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Quimiorradioterapia/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/terapia , Estudos Prospectivos , Fatores de Risco
19.
Support Care Cancer ; 29(9): 5371-5381, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33686519

RESUMO

OBJECTIVES: To explore the relationship between the Comprehensive Nutritional Index (CNI) and survival in older patients with nasopharyngeal carcinoma (NPC) and to compare the prognostic performance of three nutritional indicators (CNI, Prognostic Nutritional Index (PNI), and Nutritional Risk Index (NRI)) for overall survival (OS). METHODS: This retrospective study involved 309 older NPC patients in Guangzhou (China) from November 2006 to November 2017. The CNI comprised five parameters: the body mass index (BMI), usual body weight percentage (UBW%), hemoglobin (Hb) level, albumin level, and total lymphocyte count (TLC). All single nutritional indicators were evaluated before and immediately after treatment. The principal component analysis (PCA) was used for calculation of the CNI by single nutritional indicators after treatment. The cutoff point for the CNI was evaluated and logistic regression used to explore the risk factors for the CNI. Univariable, multivariable Cox regression, and Kaplan-Meier methods were applied for OS and disease-free survival (DFS) analyses. Cox proportional hazards models were used to compare the prognostic value of the CNI, PNI, and NRI for OS. RESULTS: All single nutritional indicators decreased significantly after treatment (P < 0.05). The CNI cutoff point for mortality was 0.027, and the logistic regression indicated more complex treatments or higher cancer stage for NPC was associated with a low CNI (HR = 0.179; 95% CI: 0.037-0.856; 0.545, 0.367-0.811, respectively). In multivariable Cox regression, the CNI remained an independent prognostic factor of OS and DFS (HR = 0.468, 95% CI: 0.263-0.832; 0.527, 0.284-0.977, respectively). Kaplan-Meier curves showed that a low CNI was associated with worse OS and DFS (P = 0.001 and 0.013, respectively). The prognostic predictive performance of the CNI was superior to that of the PNI or NRI. CONCLUSIONS: The CNI can be recommended as an appropriate indicator reflecting the integrated nutritional status of older NPC patients. A low CNI predicted a poor survival outcome and the prognostic performance of CNI was superior to PNI or NRI.


Assuntos
Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Avaliação Nutricional , Idoso , Humanos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Estado Nutricional , Prognóstico , Estudos Retrospectivos
20.
Mar Drugs ; 19(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808933

RESUMO

In this work, a non-toxic chitosan-based carrier was constructed via genipin activation and applied for the immobilization of tannase. The immobilization carriers and immobilized tannase were characterized using Fourier transform infrared spectroscopy and thermogravimetric analysis. Activation conditions (genipin concentration, activation temperature, activation pH and activation time) and immobilizations conditions (enzyme amount, immobilization time, immobilization temperature, immobilization pH, and shaking speed) were optimized. The activity and activity recovery rate of the immobilized tannase prepared using optimal activation and immobilization conditions reached 29.2 U/g and 53.6%, respectively. The immobilized tannase exhibited better environmental adaptability and stability. The immobilized tannase retained 20.1% of the initial activity after 12 cycles and retained 81.12% of residual activity after 30 days storage. The catechins composition analysis of tea extract indicated that the concentration of non-ester-type catechins, EGC and EC, were increased by 1758% and 807% after enzymatic treatment. Biological activity studies of tea extract revealed that tea extract treated with the immobilized tannase possessed higher antioxidant activity, higher inhibitory effect on α-amylase, and lower inhibitory effect on α-glucosidase. Our results demonstrate that chitosan activated with genipin could be an effective non-toxic carrier for tannase immobilization and enhancing biological activities of tea extract.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis , Hidrolases de Éster Carboxílico/metabolismo , Quitosana/química , Portadores de Fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , Iridoides/química , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Camellia sinensis/metabolismo , Hidrolases de Éster Carboxílico/química , Composição de Medicamentos , Estabilidade Enzimática , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Temperatura , Fatores de Tempo , alfa-Amilases/metabolismo
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