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1.
Analyst ; 149(7): 2051-2058, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38411001

RESUMO

A biosensor that can detect biomarkers accurately, quickly, and conveniently is important for the diagnosis of various diseases. However, most of the existing detection methods require sample extraction, which makes it difficult to detect and image intracellular molecules or to detect two different types of biomarkers simultaneously. In this study, we constructed a DNA tetrahedral nanoprobe (DTP) capable of detecting both miR378 and telomerase, both of which are tumor markers. In the presence of miR378, FAM on the molecular beacon of DTP fluoresced via Förster resonance energy transfer (FRET), and the limit of detection was 476 pM with excellent specificity. When present, telomerase binds to telomerase substrate (TS) primers, extending the repeat sequence (TTAGGG)n to trigger Cy3 fluorescence. A strong linear relationship existed between the fluorescence intensity of Cy3 and the number of HeLa cells. The limit of detection was 800 HeLa cells. In addition, DTP was less cytotoxic to and biocompatible with HeLa cells and fluoresced only in cancer cells, which can help to sensitively distinguish between normal and cancer cells. In conclusion, DTP can simultaneously detect the content of miR378 and activity of telomerase and realize intracellular imaging, which has broad application prospects in early cancer diagnosis and treatment.


Assuntos
MicroRNAs , Telomerase , Humanos , Células HeLa , Telomerase/metabolismo , Corantes Fluorescentes/química , DNA/genética , DNA/química , Imagem Óptica/métodos , Biomarcadores , MicroRNAs/genética
2.
Immunotargets Ther ; 13: 45-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38317658

RESUMO

Introduction: Chemotherapy combined with immune checkpoint inhibitors (ChIM) is used to treat advanced pancreatic ductal adenocarcinoma (PDAC). However, the efficacy of ChIM is similar to that of chemotherapy alone. Methods: To assess potential factors affecting the effectiveness of ChIM, we analyzed the clinical data of 359 patients with PDAC who visited the hospital during June 2017 to December 2022. Results: Surgical resection, diabetes, and ChIM were risk factors for pancreatic exocrine insufficiency (PEI). The adjusted odds ratio of ChIM was 2.63 (95% confidence interval (CI) 1.492-4.626) (P = 0.001). The incidence of PEI in the ChIM group (76.9%) was significantly higher than that of the chemotherapy group (60.2%) (P = 0.004). Survival analysis showed that ChIM did not improve the survival rate of patients with PDAC (hazard ratio (HR) 0.92, 0.707-1.197) (P = 0.534) in comparison with that of the chemotherapy group. However, in patients without PEI, those receiving ChIM showed a higher 1-year overall survival (OS) rate of 70.8% (two-sided, P = 0.045) and a median OS of 22.0 months (95% CI 11.5-32.5). Moreover, pancreatic enzyme replacement therapy significantly improved the OS of patients with PDAC (HR = 0.73, 95% CI = 0.561-0.956) (P = 0.022). Conclusion: Immune checkpoint inhibitors (ICIs) increased the incidence of PEI in patients with PDAC. The OS was not different between patients receiving chemotherapy and ChIM due to irregular PERT treatment. The finding show that pancreatic enzyme replacement therapy may improve the response rate of patients with PDAC to ICIs.

3.
New Phytol ; 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38402560

RESUMO

Resting cells represent a survival strategy employed by diatoms to endure prolonged periods of unfavourable conditions. In the oceans, many diatoms sink at the end of their blooming season and therefore need to endure cold and dark conditions in the deeper layers of the water column. How they survive these conditions is largely unknown. We conducted an integrative analysis encompassing methods from histology, physiology, biochemistry, and genetics to reveal the biological mechanism of resting-cell formation in the model diatom Thalassiosira pseudonana. Resting-cell formation was triggered by a decrease in light and temperature with subsequent catabolism of storage compounds. Resting cells were characterised by an acidic and viscous cytoplasm and altered morphology of the chloroplast ultrastructure. The formation of resting cells in T. pseudonana is an energy demanding process required for a biophysical alteration of the cytosol and chloroplasts to endure the unfavourable conditions of the deeper ocean as photosynthetic organisms. However, most resting cells (> 90%) germinate upon return to favorable growth conditions.

4.
Ecotoxicol Environ Saf ; 272: 116083, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350220

RESUMO

Various strategies have been explored to mitigate the impact of harmful algal blooms (HABs). While chemical and physical methods have traditionally been employed to regulate microalgal growth, their prolonged adverse effects on the ecosystem are a cause for concern. Recognizing the integral role of macroalgae within the ecosystem, this study reveals the anti-algal properties of solvent-based extracts derived from the red macroalga Pyropia haitanensis as a means of preventing microalgal blooms. In our investigation, we initially assessed the growth-inhibitory effects of methanol and acetone extracts from P. haitanensis on five microalgae known to contribute to bloom-formation. Significantly reduced growth was observed in all microalgal species when inoculated with both methanol and acetone extracts. Further analysis revealed the effectiveness of the methanol extract (ME), and further fractionation with petroleum ether (PE), ethyl acetate (EA), and n-butanol (NB) for testing against Skeletonema costatum and Pseudo-nitzschia pungens. The methanol fractions exhibited strong inhibition, resulting in the complete elimination of both microalgae after 96 hours of exposure to PE, EA, and NB extracts. Gas Chromatography-Mass Spectroscopy (GC-MS) analysis of the ME and its solvent fractions identified 49 confirmed compounds. These compounds are likely potential contributors to the observed inhibition of microalgal growth. In conclusion, our findings suggest that solvent extracts from P. haitanensis possess substantial potential for the control of HABs, offering a promising avenue for further research and application in ecosystem management.


Assuntos
Microalgas , Rodófitas , Alga Marinha , Solventes , Ecossistema , Metanol , Acetona , Proliferação Nociva de Algas
5.
Anim Genet ; 55(2): 265-276, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38185881

RESUMO

In livestock, genome-wide association studies (GWAS) are usually conducted in a single population (single-GWAS) with limited sample size and detection power. To enhance the detection power of GWAS, meta-analysis of GWAS (meta-GWAS) and mega-analysis of GWAS (mega-GWAS) have been proposed to integrate data from multiple populations at the level of summary statistics or individual data, respectively. However, there is a lack of comparison for these different strategies, which makes it difficult to guide the best practice of GWAS integrating data from multiple study populations. To maximize the comparison of different association analysis strategies across multiple populations, we conducted single-GWAS, meta-GWAS, and mega-GWAS for the backfat thickness of 100 kg (BFT_100) and days to 100 kg (DAYS_100) within each of the three commercial pig breeds (Duroc, Yorkshire, and Landrace). Based on controlling the genome inflation factor to one, we calculated corrected p-values (pC ). In Yorkshire, with the largest sample size, mega-GWAS, meta-GWAS and single-GWAS detected 149, 38 and 20 significant SNPs (pC < 1E-5) associated with BFT_100, as well as 26, four, and one QTL, respectively. Among them, pC of SNPs from mega-GWAS was the lowest, followed by meta-GWAS and single-GWAS. The correlation of pC among the three GWAS strategies ranged from 0.60 to 0.75 and the correlation of SNP effect values between meta-GWAS and mega-GWAS was 0.74, all showing good agreement. Collectively, even though there are differences in the integration of individual data or summary statistics, integrating data from multiple populations is an effective means of genetic argument for complex traits, especially mega-GWAS versus single-GWAS.


Assuntos
Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Suínos , Animais , Polimorfismo de Nucleotídeo Único , Herança Multifatorial , Fenótipo
6.
Neuropsychiatr Dis Treat ; 20: 69-81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38249525

RESUMO

Purpose: The Coronavirus disease 2019 (COVID-19) remains a global public health concern. Many people have been forced to change their lifestyles, which has led to psychological and sleep problem. This study aims to investigate the psychological health problems and factors among patients in the Fangcang Shelter Hospital (FSH) during the COVID-19 pandemic. Patients and Methods: A Cross-Sectional survey was conducted to investigate the sleep, anxiety, depression and stress disorders of 2628 asymptomatic and mild patients treated in FSH of Zhengzhou, Henan Province, from 30 October to 6 December 2022, by scanning a WeChat two-dimensional code. Sociodemographic data and influencing factors in FSH were collected, Insomnia Severity Index (ISI), 9-item Patient Health Questionnaire (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Impact of Event Scale-Revised (IES-R) were administered. Descriptive statistics, t-tests or analysis of variance, Spearman or Pearson correlation analysis, and multivariate regression analysis were used to explore the relationships between different variables and their impact on psychological health indicators. Results: The proportions of patients with insomnia, depressive disorder, anxiety, and stress disorders were 33.49%, 35.80%, 31.74%, and 43.57%, respectively. Spearman correlation analysis demonstrated that factors such as gender, higher education level, positive nucleic acid test results, longer illness duration, underlying diseases, and extended electronic device use were associated with elevated psychological distress scores. Notably, within FSH, extended exposure to light, a noisy environment, and sleep schedule management significantly impacted the prevalence of insomnia, depression, anxiety, and stress disorders (p<0.01). Multivariable binary logistic regression analysis identified higher education level, light exposure, noisy environment, sleep management, and electronic device usage as the primary risk factors for psychological distress. Conclusion: Patients in FSH face psychological distress influenced by sociodemographic factors, environment, and lifestyle, highlighting the need for integrated psychological support in healthcare, particularly in temporary medical facilities during crises.

7.
Nat Genet ; 56(1): 112-123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177344

RESUMO

The Farm Animal Genotype-Tissue Expression (FarmGTEx) project has been established to develop a public resource of genetic regulatory variants in livestock, which is essential for linking genetic polymorphisms to variation in phenotypes, helping fundamental biological discovery and exploitation in animal breeding and human biomedicine. Here we show results from the pilot phase of PigGTEx by processing 5,457 RNA-sequencing and 1,602 whole-genome sequencing samples passing quality control from pigs. We build a pig genotype imputation panel and associate millions of genetic variants with five types of transcriptomic phenotypes in 34 tissues. We evaluate tissue specificity of regulatory effects and elucidate molecular mechanisms of their action using multi-omics data. Leveraging this resource, we decipher regulatory mechanisms underlying 207 pig complex phenotypes and demonstrate the similarity of pigs to humans in gene expression and the genetic regulation behind complex phenotypes, supporting the importance of pigs as a human biomedical model.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Suínos/genética , Animais , Humanos , Genótipo , Fenótipo , Análise de Sequência de RNA
8.
Nucleic Acids Res ; 52(D1): D980-D989, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37956339

RESUMO

To fully unlock the potential of pigs as both agricultural species for animal-based protein food and biomedical models for human biology and disease, a comprehensive understanding of molecular and cellular mechanisms underlying various complex phenotypes in pigs and how the findings can be translated to other species, especially humans, are urgently needed. Here, within the Farm animal Genotype-Tissue Expression (FarmGTEx) project, we build the PigBiobank (http://pigbiobank.farmgtex.org) to systematically investigate the relationships among genomic variants, regulatory elements, genes, molecular networks, tissues and complex traits in pigs. This first version of the PigBiobank curates 71 885 pigs with both genotypes and phenotypes from over 100 pig breeds worldwide, covering 264 distinct complex traits. The PigBiobank has the following functions: (i) imputed sequence-based genotype-phenotype associations via a standardized and uniform pipeline, (ii) molecular and cellular mechanisms underlying trait-associations via integrating multi-omics data, (iii) cross-species gene mapping of complex traits via transcriptome-wide association studies, and (iv) high-quality results display and visualization. The PigBiobank will be updated timely with the development of the FarmGTEx-PigGTEx project, serving as an open-access and easy-to-use resource for genetically and biologically dissecting complex traits in pigs and translating the findings to other species.


Assuntos
Bases de Dados Genéticas , Suínos , Animais , Estudo de Associação Genômica Ampla , Genótipo , Herança Multifatorial , Fenótipo , Suínos/genética , Multiômica
9.
Cell Genom ; 3(10): 100385, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37868035

RESUMO

Many quantitative trait loci (QTLs) are in non-coding regions. Therefore, QTLs are assumed to affect gene regulation. Gene expression and RNA splicing are primary steps of transcription, so DNA variants changing gene expression (eVariants) or RNA splicing (sVariants) are expected to significantly affect phenotypes. We quantify the contribution of eVariants and sVariants detected from 16 tissues (n = 4,725) to 37 traits of ∼120,000 cattle (average magnitude of genetic correlation between traits = 0.13). Analyzed in Bayesian mixture models, averaged across 37 traits, cis and trans eVariants and sVariants detected from 16 tissues jointly explain 69.2% (SE = 0.5%) of heritability, 44% more than expected from the same number of random variants. This 69.2% includes an average of 24% from trans e-/sVariants (14% more than expected). Averaged across 56 lipidomic traits, multi-tissue cis and trans e-/sVariants also explain 71.5% (SE = 0.3%) of heritability, demonstrating the essential role of proximal and distal regulatory variants in shaping mammalian phenotypes.

10.
BMC Genomics ; 24(1): 628, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37865759

RESUMO

BACKGROUND: The survival and fertility of heifers are critical factors for the success of dairy farms. The mortality of heifers poses a significant challenge to the management and profitability of the dairy industry. In dairy farming, achieving early first calving of heifers is also essential for optimal productivity and sustainability. Recently, Council on Dairy Cattle Breeding (CDCB) and USDA have developed new evaluations of heifer health and fertility traits. However, the genetic basis of these traits has yet to be thoroughly studied. RESULTS: Leveraging the extensive U.S dairy genomic database maintained at CDCB, we conducted large-scale GWAS analyses of two heifer traits, livability and early first calving. Despite the large sample size, we found no major QTL for heifer livability. However, we identified a major QTL in the bovine MHC region associated with early first calving. Our GO analysis based on nearby genes detected 91 significant GO terms with a large proportion related to the immune system. This QTL in the MHC region was also confirmed in the analysis of 27 K bull with imputed sequence variants. Since these traits have few major QTL, we evaluated the genome-wide distribution of GWAS signals across different functional genomics categories. For heifer livability, we observed significant enrichment in promotor and enhancer-related regions. For early calving, we found more associations in active TSS, active Elements, and Insulator. We also identified significant enrichment of CDS and conserved variants in the GWAS results of both traits. By linking GWAS results and transcriptome data from the CattleGTEx project via TWAS, we detected four and 23 significant gene-trait association pairs for heifer livability and early calving, respectively. Interestingly, we discovered six genes for early calving in the Bovine MHC region, including two genes in lymph node tissue and one gene each in blood, adipose, hypothalamus, and leukocyte. CONCLUSION: Our large-scale GWAS analyses of two heifer traits identified a major QTL in the bovine MHC region for early first calving. Additional functional enrichment and TWAS analyses confirmed the MHC QTL with relevant biological evidence. Our results revealed the complex genetic basis of heifer health and fertility traits and indicated a potential connection between the immune system and reproduction in cattle.


Assuntos
Estudo de Associação Genômica Ampla , Reprodução , Bovinos/genética , Animais , Feminino , Masculino , Estudo de Associação Genômica Ampla/veterinária , Fertilidade/genética , Genoma , Fenótipo
11.
J Agric Food Chem ; 71(44): 16752-16762, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37822021

RESUMO

Fumonisin B1 (FB1) is a representative form of fumonisin and is widely present in food and feed. Hydrolyzed fumonisin B1 (HFB1) emerges as a breakdown product of FB1, which is accompanied by FB1 alterations. While previous studies have primarily focused on the liver or kidney toxicity of FB1, with limited studies existing on its neurotoxicity and even fewer on the toxicity of HFB1, this study focuses on the neurotoxicity of FB1 and HFB1 exposure in mice investigated by the open field test, Morris water maze test, histopathological analysis, and nontargeted metabolomics. Further, the levels of oxidative stress-related indices, neurotransmitters, and sphingolipids in the brain were measured to analyze their correlation with behavioral outcomes. The results showed that both FB1 (5 mg/kg) and HFB1 (2.8 mg/kg) reduced autonomous exploratory behavior in mice, impaired spatial learning and memory, and caused mild abnormalities in the brain structure. Quantitative analysis further indicated that exposure to FB1 and HFB1 disrupted neurotransmitter homeostasis, exacerbated oxidative stress, and significantly increased the sphinganine/sphingosine (Sa/So) ratio. Moreover, HFB1 exhibited neurotoxic effects similar to those of FB1, emphasizing the need to pay attention to the neurotoxicity effect of HFB1. These findings underscore the importance of understanding the risks and potential neurological damage associated with FB1 and HFB1 exposure, highlighting the necessity for further research in this crucial field.


Assuntos
Fumonisinas , Camundongos , Animais , Fumonisinas/análise , Memória Espacial , Esfingolipídeos , Fígado/metabolismo
12.
Int J Mol Sci ; 24(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37761980

RESUMO

Although estuarine diatoms have a wide range of salt tolerance, they are often severely stressed by elevated salt concentrations. It remains poorly understood how estuarine diatoms maintain ionic homeostasis under high-salinity conditions. Using a scanning ion-selective electrode technique, this study determined the fluxes of H+, Na+, and K+ involved in the acclimatization of the estuarine diatom Coscinodiscus centralis Ehrenberg after an elevation in salinity from 15 psu to 35 psu. The C. centralis cells exhibited marked H+ effluxes after a transient treatment (TT, 30 min) and short-term treatment (ST, 24 h). However, a drastic shift of H+ efflux toward an influx was induced in the long-term treatment (LT, 10 days). The Na+ flux under TT, ST, and LT salinity conditions was found to accelerate the Na+ efflux. More pronounced effects were observed under the ST and LT salinity conditions compared to the TT salinity condition. The K+ influx showed a significant increase under the LT salinity condition. However, the salinity-induced Na+/H+ exchange in the estuarine diatom was inhibited by amiloride and sodium orthovanadate. These results indicate that the Na+ extrusion in salt-stressed cells is mainly the result of an active Na+/H+ antiport across the plasma membrane. The pattern of ion fluxes under the TT and ST salinity conditions were different from those under the LT salinity conditions, suggesting an incomplete regulation of the acclimation process in the estuarine diatom under short-term salinity stress.

13.
Foods ; 12(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37628077

RESUMO

Rare sugars possess potential applications as low-calorie sweeteners, especially for anti-obesity and anti-diabetes. In this study, a fermentation biosystem based on the "DHAP-dependent aldolases strategy" was established for D-allulose and D-sorbose production from glycerol in endotoxin-free ClearColi BL21 (DE3). Several engineering strategies were adopted to enhance rare sugar production. Firstly, the combination of different plasmids for aldO, rhaD, and yqaB expression was optimized. Then, the artificially constructed ribosomal binding site (RBS) libraries of aldO, rhaD, and yqaB genes were assembled individually and combinatorially. In addition, a peroxidase was overexpressed to eliminate the damage or toxicity from hydrogen peroxide generated by alditol oxidase (AldO). Finally, stepwise improvements in rare sugar synthesis were elevated to 15.01 g/L with a high yield of 0.75 g/g glycerol in a 3 L fermenter. This research enables the effective production of rare sugars from raw glycerol in high yields.

14.
Commun Biol ; 6(1): 894, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652983

RESUMO

Transposable elements (TEs) are a major source of genetic polymorphisms and play a role in chromatin architecture, gene regulatory networks, and genomic evolution. However, their functional role in pigs and contributions to complex traits are largely unknown. We created a catalog of TEs (n = 3,087,929) in pigs and found that young SINEs were predominantly silenced by histone modifications, DNA methylation, and decreased accessibility. However, some transcripts from active young SINEs showed high tissue-specificity, as confirmed by analyzing 3570 RNA-seq samples. We also detected 211,067 dimorphic SINEs in 374 individuals, including 340 population-specific ones associated with local adaptation. Mapping these dimorphic SINEs to genome-wide associations of 97 complex traits in pigs, we found 54 candidate genes (e.g., ANK2 and VRTN) that might be mediated by TEs. Our findings highlight the important roles of young SINEs and provide a supplement for genotype-to-phenotype associations and modern breeding in pigs.


Assuntos
Regulação da Expressão Gênica , Herança Multifatorial , Suínos/genética , Animais , Redes Reguladoras de Genes , Polimorfismo Genético , Elementos Nucleotídeos Curtos e Dispersos
15.
BMC Genom Data ; 24(1): 39, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550629

RESUMO

OBJECTIVES: This study was performed in the frame of a more extensive study dedicated to the integrated analysis of the single-cell transcriptome and chromatin accessibility datasets of peripheral blood mononuclear cells (PBMCs) with a large-scale GWAS of 45 complex traits in Chinese Holstein cattle. Lipopolysaccharide (LPS) is a crucial mediator of chronic inflammation to modulate immune responses. PBMCs include primary T and B cells, natural killer (NK) cells, monocytes (Mono), and dendritic cells (DC). How LPS stimulates PBMCs at the single-cell level in dairy cattle remains largely unknown. DATA DESCRIPTION: We sequenced 30,756 estimated single cells and mapped 26,141 of them (96.05%) with approximately 60,075 mapped reads per cell after quality control for four whole-blood treatments (no, 2 h, 4 h, and 8 h LPS) by single-cell RNA sequencing (scRNA-seq) and single-cell sequencing assay for transposase-accessible chromatin (scATAC-seq). Finally, 7,107 (no), 9,174 (2 h), 6,741 (4 h), and 3,119 (8 h) cells were generated with ~ 15,000 total genes in the whole population. Therefore, the single-cell transcriptome and chromatin accessibility datasets in this study enable a further understanding of the cell types and functions of PBMCs and their responses to LPS stimulation in vitro.


Assuntos
Cromatina , Transcriptoma , Bovinos , Animais , Transcriptoma/genética , Cromatina/genética , Leucócitos Mononucleares , Lipopolissacarídeos/farmacologia , Sequência de Bases
16.
Biotechnol J ; 18(11): e2300259, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37470505

RESUMO

BACKGROUND: Human lysozyme (hLYZ), an emerging antibacterial agent, has extensive application in the food and pharmaceutical industries. However, the source of hLYZ is particularly limited. RESULTS: To achieve highly efficient expression and secretion of hLYZ in Pichia pastoris, multiple strategies including G418 sulfate screening, signal sequence optimization, vacuolar sorting receptor VPS10 disruption, and chaperones/transcription factors co-expression were applied. The maximal enzyme activity of extracellular hLYZ in a shaking flask was 81,600 ± 5230 U mL-1 , which was about five times of original strain. To further reduce the cost, the optimal medium RDMY was developed and the highest hLYZ activity reached 352,000 ± 16,696.5 U mL-1 in a 5 L fermenter. CONCLUSION: This research provides a very useful and cost-effective approach for the hLYZ production in P. pastoris and can also be applied to the production of other recombinant proteins.


Assuntos
Muramidase , Saccharomycetales , Humanos , Muramidase/genética , Pichia , Proteínas Recombinantes/metabolismo , Saccharomycetales/metabolismo
17.
Environ Res ; 235: 116568, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37422114

RESUMO

The "larval starvation hypothesis" proposed that the growing frequency of Crown-of-Thorns Starfish (CoTS) outbreaks could be attributed to increased availability of phytoplankton. However, comprehensive field investigation on the living environment of CoTS larvae and the availability of phytoplankton are still lacking. A cruise was conducted in June 2022 in Xisha Islands, South China Sea, to study the interaction between environmental conditions and phytoplankton communities during CoTS outbreak period. The average concentrations of dissolved inorganic phosphorus (0.05 ± 0.01 µmol L-1), dissolved inorganic nitrogen (0.66 ± 0.8 µmol L-1) and chlorophyll a (0.05 ± 0.05 µg L-1) suggested that phytoplankton may be limited for CoTS larvae in Xisha Islands. Microscopic observation and high-throughput sequencing were used to study the composition and structure of the phytoplankton communities. Bacillariophyta predominated in phytoplankton communities with the highest abundance and species richness. 29 dominant species, including 4 species with size-range preferred by CoTS larvae, were identified in Xisha Islands. The diversity index of all stations indicated a species-rich and structure-stable phytoplankton community in Xisha Islands during the period of CoTS outbreak, which may contribute to CoTS outbreak. These findings revealed the structure of phytoplankton community and environmental factors in the study area during CoTS outbreak, providing the groundwork for future research into the causes and processes of CoTS outbreak.


Assuntos
Fitoplâncton , Estrelas-do-Mar , Animais , Clorofila A , Ilhas , Surtos de Doenças , China/epidemiologia
18.
Biotechnol Lett ; 45(10): 1355-1364, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37486554

RESUMO

PURPOSE: In our previous study, we constructed a one-pot multi-enzyme system for rare ketoses synthesis based on L-rhamnulose-1-phosphate aldolase (RhaD) from accessible glycerol in vitro. To eliminate tedious purification of enzymes, a facile Escherichia coli whole-cell cascade platform was established in this study. METHODS: To enhance the conversion rate, the reaction conditions, substrate concentrations and expressions of related enzymes were extensively optimized. RESULTS: The biosynthetic route for the cascade synthesis of rare ketoses in whole cells was successfully constructed and three rare ketoses including D-allulose, D-sorbose and L-fructose were produced using glycerol and D/L-glyceraldehyde (GA). Under optimized conditions, the conversion rates of rare ketoses were 85.0% and 93.0% using D-GA and L-GA as the receptor, respectively. Furthermore, alditol oxidase (AldO) was introduced to the whole-cell system to generate D-GA from glycerol, and the total production yield of D-sorbose and D-allulose was 8.2 g l-1 only from the sole carbon source glycerol. CONCLUSION: This study demonstrates a feasible and cost-efficient method for rare sugars synthesis and can also be applied to the green synthesis of other value-added chemicals from glycerol.


Assuntos
Cetoses , Sorbose , Sorbose/química , Glicerol/metabolismo , Gliceraldeído/química , Gliceraldeído/metabolismo
20.
Mol Neurobiol ; 60(10): 5931-5943, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37380823

RESUMO

Neuronal swelling is a pathological feature of stroke which contributes to the formation of cytotoxic edema. Under hypoxic condition, aberrant accumulation of sodium and chloride ions inside neurons increases osmotic pressure, leading to cell volume increase. Sodium entry pathway in neurons has been studied extensively. Here, we determine whether SLC26A11 is the major chloride entry pathway under hypoxia and could be the target for protection against ischemic stroke. In this study, electrophysiological properties of chloride current in primary cultured neurons were characterized using low chloride solution, 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid, and SLC26A11-specific siRNA under physiological conditions or ATP-depleted conditions. In vivo effect of SLC26A11 was evaluated on a rat stroke reperfusion model. We found that SLC26A11 mRNA in primary cultured neurons was upregulated as early as 6 h after oxygen glucose deprivation, and later, the protein level was elevated accordingly. Blockade of SLC26A11 activity could reduce chloride entry and attenuate hypoxia-induced neuronal swelling. In the animal stroke model, SLC26A11 upregulation was mainly located in surviving neurons close to the infarct core. SLC26A11 inhibition ameliorates infarct formation and improves functional recovery. These findings demonstrate that SLC26A11 is a major pathway for chloride entry in stroke, contributing to neuronal swelling. Inhibition of SLC26A11 could be a novel therapeutic strategy for stroke.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Ratos , Animais , Cloretos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Hipóxia/patologia , Edema , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Infarto , Sódio/metabolismo , Glucose , Isquemia Encefálica/patologia
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