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1.
Clin Transplant ; 38(4): e15300, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38555576

RESUMO

Cytomegalovirus (CMV) reactivation remains one of the major and life-threatening complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Yet, there is still a lack of safe and effective ways to prevent CMV reactivation in allo-HSCT patients. Here, we retrospectively analyzed a cohort of patients who underwent HSCT at our transplant center between 2018 and 2022 to evaluate the efficacy of prophylactic CMV-specific intravenous immunoglobulin (CMV-IVIg) against CMV reactivation. After Propensity Score Matching, the CMV reactivation rate was significantly decreased in the CMV-IVIg group (HR, 2.952; 95% CI,1.492-5.841; P = .002) compared with the control group. Additionally, the time duration of CMV reactivation (P = .001) and bacterial infection rate (P = .013) were significantly lower in the CMV-IVIg group. Moreover, prophylactic CMV-IVIg was more effective in CMV seropositive patients who received ATG as part of GVHD prevention (HR, 8.225; 95% CI,1.809-37.39; P = .006). In conclusion, CMV-IVIg is considered an effective and safe way to prevent CMV reactivation in HSCT recipients, which may be related to the acceleration of immune reconstitution in the early stage after transplantation.


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Humanos , Citomegalovirus , Imunoglobulinas Intravenosas/uso terapêutico , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/tratamento farmacológico , Estudos Retrospectivos , Transplante Homólogo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Anticorpos Antivirais
2.
Analyst ; 148(16): 3708-3718, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37489761

RESUMO

Hepatitis B virus (HBV) infection is a major global health problem of widespread concern. Clinically, serological assays are the most widely used diagnostic tests for HBV infection, with the presence of HBsAg in the serum being indicative of acute and chronic hepatitis B infection. However, increased identification of HBV DNA positive but HBsAg negative cases has greatly promoted the use of molecular assays for more accurate HBV diagnosis. Over the past few decades, especially since the outbreak of COVID-19, significant advancements have been made in the techniques and devices for nucleic acid testing (NAT). Nowadays, the mainstream NAT techniques can broadly be split into two categories: PCR-based methods and non-PCR-based isothermal amplification methods. As achieving point-of-care testing (POCT) or on-site testing is an important development tendency for the next-generation NAT, non-PCR-based isothermal amplification methods like nucleic acid sequence-based amplification (NASBA), rolling circle amplification (RCA), loop-mediated isothermal amplification (LAMP), helicase-dependent amplification (HDA), and recombinase polymerase amplification (RPA) have garnered significant attention in recent years. In this review, we provide a comprehensive overview of the nucleic acid isothermal amplification technologies currently used for HBV detection. The analytical performances of different methods are compared and their integration with microfluidics, lateral flow assays, and CRISPR/Cas systems is also discussed.


Assuntos
COVID-19 , Hepatite B , Humanos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA , Hepatite B/diagnóstico , Hepatite B/epidemiologia
3.
Virus Genes ; 59(2): 290-300, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36607487

RESUMO

A lysogenic phage vB_EcoP_DE5 (hereafter designated DE5) was isolated from donkey-derived Escherichia coli. The bacteriophage was examined by transmission electron microscopy, and the result showed that DE5 belonged to the genus Kuravirus. DE5 was sensitive to changes in temperature and pH, and it could maintain its activity at pH 7 and below 60 â„ƒ. The whole genome sequencing revealed that DE5 had a double-stranded DNA genome of 77, 305 bp with 42.09% G+C content. A total of 126 open reading frames (ORFs) were identified, including functional genes related to phage integration, DNA replication and modification, transcriptional regulation, structural and packaging proteins, and host cell lysis. One phage integrase gene, one autotransporter adhesin gene, and one tRNA gene were predicted in the whole genome, and no genes associated with drug resistance were identified. The phage DE5 integrase contained 187 amino acids and belonged to the small serine recombinase family. BLASTn analysis revealed that phage DE5 had a high-sequence identity (96%) with E. coli phage SU10. Phylogenetic analysis showed that phage DE5 was a member of the genus Kuravirus. The whole genome sequencing of lysogenic phage DE5 enhanced our understanding of lysogenic phages and their therapeutic applications.


Assuntos
Bacteriófagos , Podoviridae , Bacteriófagos/genética , Escherichia coli/genética , Filogenia , Genoma Viral , Podoviridae/genética , Sequenciamento Completo do Genoma , Integrases/genética , Fases de Leitura Aberta
4.
Virus Genes ; 59(5): 752-762, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37322310

RESUMO

Bacteriophages are an important source of novel genetic diversity. Sequencing of phage genomes can reveal new proteins with potential uses in phage therapy and help unravel the diversity of biological mechanisms by which phages take over the machinery of the host during infection. To expand the available collection of phage genomes, we have isolated, sequenced, and assembled the genome sequences of three phages that infect three pathogenic Escherichia coli strains: vB_EcoM_DE15, vB_EcoM_DE16, and vB_EcoM_DE17. Morphological characterization and genomic analysis indicated that all three phages were strictly lytic and free from integrases, virulence factors, toxins, and antimicrobial resistance genes. All three phages contained tRNAs, and especially, vB_EcoM_DE17 contained 25 tRNAs. The genomic features of these phages indicate that natural phages are capable of lysing pathogenic E.coli and have great potential in the biocontrol of bacteria.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Escherichia coli/genética , Genoma Viral , Genômica , Bactérias
5.
J Environ Manage ; 334: 117476, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36773452

RESUMO

Investigation of the inherent relationship between soil physicochemical properties and pollutant's bioaccessibility (BAc) by analyzing different soil types may produce erroneous results or bias, owing to the complexity of natural soil characteristics. However, use of single factor analysis (e.g., soil pH, organic matter) facilitates evaluation of the transition. In this study, the inherent relationship between soil properties and the BAc of molybdenum (Mo) was evaluated in two typical variable-charge soils (Ferralosol and Ferrosol) and constant-charge soils (Alfisol and Inceptisol) spiked with Mo after adjusting their pH and organic carbon content. The Unified Bioaccessibility Research Group of Europe (BARGE) Method (UBM) was applied to evaluate the BAc of Mo in the gastric and intestinal phase (GP and IP, respectively). Isothermal adsorption experiment, Tessier sequential extraction, and field emission scanning electron microscope-energy dispersive spectroscopy (FESEM-EDS) analysis were conducted on these spiked soils. The results indicated that the BAc of Mo in IP (27.42-80.41%) was significantly higher than that in GP (2.52-28.53%). A significantly lower level of BAc of Mo was found in the variable-charge soils, when compared with that in the constant-charge soils. Furthermore, significant negative correlations were identified between the BAc and adsorption of Mo, which decreased with soil pH. These negative correlations can be attributed to the increase in soil negative charge density and enhancement of Mo desorption by hydroxyl, which reinforce the repulsion between Mo and soil particles with increasing soil pH; this was further confirmed by the decrease in Mo adsorption with Alfisol pH. The Mo fractions and FESEM-EDS patterns confirmed that the BAc of Mo in GP was negatively correlated with soil organic carbon (SOC) content, possibly owing to an increase in Mo retention by SOC. These findings indicated that the health risk of Mo contamination in low pH and SOC-rich variable-charge soil is relatively low, thus providing references for rationalizing risk assessment and remediating Mo-polluted soil.


Assuntos
Poluentes do Solo , Solo , Solo/química , Molibdênio/análise , Carbono/análise , Poluentes do Solo/química , Disponibilidade Biológica , Concentração de Íons de Hidrogênio
6.
Opt Express ; 30(11): 19544-19556, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221728

RESUMO

Quartz glass has a wide range of application and commercial value due to its high light transmittance and stable chemical and physical properties. However, due to the difference in the characteristics of the material itself, the adhesion between the metal micropattern and the glass material is limited. This is one of the main things that affect the application of glass surface metallization in the industry. In this paper, micropatterns on the surface of quartz glass are fabricated by a femtosecond laser-induced backside dry etching (fs-LIBDE) method to generate the layered composite structure and the simultaneous seed layer in a single-step. This is achieved by using fs-LIBDE technology with metal base materials (Stainless steel, Al, Cu, Zr-based amorphous alloys, and W) with different ablation thresholds, where atomically dispersed high threshold non-precious metals ions are gathered across the microgrooves. On account of the strong anchor effect caused by the layered composite structures and the solid catalytic effect that is down to the seed layer, copper micropatterns with high bonding strength and high quality, can be directly prepared in these areas through a chemical plating process. After 20-min of sonication in water, no peeling is observed under repeated 3M scotch tape tests and the surface was polished with sandpapers. The prepared copper micropatterns are 18 µm wide and have a resistivity of 1.96 µΩ·cm (1.67 µΩ·cm for pure copper). These copper micropatterns with low resistivity has been proven to be used for the glass heating device and the transparent atomizing device, which could be potential options for various microsystems.

7.
Bioorg Chem ; 120: 105605, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35081479

RESUMO

Although several Epidermal growth factor receptor (EGFR) inhibitors have been approved for the treatment of non-small-cell lung cancers (NSCLC), acquired drug resistance and side effects largely encumbered their application in clinic. The emerging technology Proteolysis targeting chimera (PROTAC) could be an alternative strategy to overcome these problems. Here, we reported the discovery of Dacomitinib-based EGFR degraders. Promising compound 13 can effectively induce degradation of EGFRdel19 with DC50 value of 3.57 nM in HCC-827 cells, but not to other EGFR mutant, wild-type EGFR protein and the same family receptors (HER2 and HER4). Of note, 13 is the first EGFR-PROTAC to evaluate antitumor effect in vivo, and exhibited excellent antitumor efficacy (TGI = 90%) at a dose of 30 mg/kg without causing observable toxic effects. The preliminary mechanism study demonstrated that 13 can efficiently induce EGFR protein degradation through ubiquitin proteasome pathway and inhibit phosphorylation of downstream pathways in vitro and in vivo, which indicated that 13 exerted antitumor effect by degradation of EGFR protein in tumor tissue. Overall, our study provided further evidence to validate EGFR-PROTACs as a promising strategy for lung cancer therapy.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Receptores ErbB , Humanos , Neoplasias Pulmonares/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Proteólise
8.
Microb Cell Fact ; 19(1): 32, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054531

RESUMO

BACKGROUND: Bleomycin is a broad-spectrum glycopeptide antitumor antibiotic produced by Streptomyces verticillus. Clinically, the mixture of bleomycin A2 and bleomycin B2 is widely used in combination with other drugs for the treatment of various cancers. As a secondary metabolite, the biosynthesis of bleomycin is precisely controlled by the complex extra-/intracellular regulation mechanisms, it is imperative to investigate the global metabolic and regulatory system involved in bleomycin biosynthesis for increasing bleomycin production. RESULTS: N-acetylglucosamine (GlcNAc), the vital signaling molecule controlling the onset of development and antibiotic synthesis in Streptomyces, was found to increase the yields of bleomycins significantly in chemically defined medium. To mine the gene information relevant to GlcNAc metabolism, the DNA sequences of dasR-dasA-dasBCD-nagB and nagKA in S. verticillus were determined by chromosome walking. From the results of Real time fluorescence quantitative PCR (RT-qPCR) and electrophoretic mobility shift assays (EMSAs), the repression of the expression of nagB and nagKA by the global regulator DasR was released under induction with GlcNAc. The relief of blmT expression repression by BlmR was the main reason for increased bleomycin production. DasR, however, could not directly affect the expression of the pathway-specific repressor BlmR in the bleomycins gene cluster. With at the beginning of bleomycin synthesis, the supply of the specific precursor GDP-mannose played the key role in bleomycin production. Genetic engineering of the GDP-mannose synthesis pathway indicated that phosphomannose isomerase (ManA) and phosphomannomutase (ManB) were key enzymes for bleomycins synthesis. Here, the blmT, manA and manB co-expression strain OBlmT/ManAB was constructed. Based on GlcNAc regulation and assisted metabolic profiling analysis, the yields of bleomycin A2 and B2 were ultimately increased to 61.79 and 36.9 mg/L, respectively. CONCLUSIONS: Under GlcNAc induction, the elevated production of bleomycins was mainly associated with the alleviation of the inhibition of BlmT, so blmT and specific precursor synthesis pathways were genetically engineered for bleomycins production improvement. Combination with subsequent metabolomics analysis not only effectively increased the bleomycin yield, but also extended the utilization of chitin-derived substrates in microbial-based antibiotic production.


Assuntos
Acetilglucosamina/metabolismo , Bleomicina/biossíntese , Guanosina Difosfato Manose/metabolismo , Streptomyces/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Redes e Vias Metabólicas , Metabolômica/métodos , Metabolismo Secundário
9.
Bioprocess Biosyst Eng ; 43(2): 303-313, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31605206

RESUMO

Bioremediation methods have been successfully applied to the removal of organic pollutants for decades, but the responses of the microbial community to environmental factors remain less well known. In this work, the degradation rates of petroleum hydrocarbons (PHs) reached up to 50.11% ± 2.74% after optimizing the degradation conditions. Under the influence of the optimized degradation conditions, the diversity of the bacterial community gradually increased. Meanwhile, the dominant bacterial genera, encompassing Burkholderia-Paraburkholderia, Luteibacter, and Acinetobacter, remained stable. Moreover, statistical analysis indicated that the genera Bacterium, Burkholderia-Paraburkholderia, Luteibacter, and Acinetobacter contributed the most to PHs degradation. Additionally, the functional modules of amino acid metabolism, carbohydrate metabolism, as well as global and overview maps played a vital role in the metabolization of PHs. Therefore, understanding the changes of the microbial community structure and function can provide valuable guidance to further improve the degradation rate of organic waste via bioremediation methods.


Assuntos
Bactérias , Microbiota , Poluição por Petróleo , Petróleo/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental
10.
Kidney Blood Press Res ; 44(6): 1313-1326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31639799

RESUMO

BACKGROUND: The interaction of environmental factors and genetic factors may contribute to the risk of type 2 diabetes (T2D). We aimed to investigate whether age, gender, body mass index (BMI) and lifestyle factors have an effect on the association between the CDKAL1 polymorphisms and T2D. METHODS: Eight single nucleotide polymorphisms in CDKAL1 were genotyped by Agena MassARRAY in 508 T2D patients and 503 controls. The association between the CDKAL1 polymorphisms and T2D was evaluated using logistic regression model by calculating OR and 95% CIs. RESULTS: We found a significant association between CDKAL1 polymorphisms (rs4712523, OR 1.42, p = 9.44 × 10-5; rs4712524, OR 1.38, p = 3.28 × 10-4; rs10946398, OR 1.43, p = 6.21 × 10-5; rs7754840, OR 1.43, p = 6.33 × 10-5; rs35612982, OR 1.34, p = 0.0010; and rs10440833, OR 1.32, p = 0.0018) and T2D risk among the Han population from Northwest China. We also found that genetic variants of CDKAL1 could modify the risk of T2D that might be influenced by age, BMI and the status of smoking and drinking. Besides, rs35612982-CT (p = 0.038) and rs10440833-AT (p = 0.044) genotypes were higher insulin level. CONCLUSION: CDKAL1 rs35612982 (C/T) polymorphism, as a new polymorphism, was associated with the increased risk of T2D in the Han Chinese population. Moreover, the contribution of CDKAL1 polymorphisms to T2D risk seems to be associated with age, gender, BMI, smoking and drinking.


Assuntos
Diabetes Mellitus Tipo 2/genética , Polimorfismo Genético , tRNA Metiltransferases/genética , Adulto , Fatores Etários , Índice de Massa Corporal , Estudos de Casos e Controles , China/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais
11.
Appl Microbiol Biotechnol ; 103(16): 6629-6644, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187208

RESUMO

Bleomycin, a broad-spectrum antibiotic, has been widely used for various tumor treatments. However, its poor fermentation yield is not satisfactory for industrial production. Here, the ArsR/SmtB family regulator BlmR was characterized as a repressor of bleomycin production. As an autoregulator, BlmR was found to bind to a 12-2-12 imperfect palindrome sequence in its own promoter, and deletion of blmR led to a 34% increase of bleomycin B2 production compared with the wild-type strain. Using reverse transcription and quantitative PCR (RT-qPCR), blmT, which encoded a putative transporter, was identified as the target gene regulated by BlmR. Therefore, high-production strain was constructed by blmT overexpression in a blmR deletion strain, and the bleomycin B2 titer reached to 80 mg/L, which was 1.9-fold higher than the wild-type strain. Moreover, electrophoretic mobility shift assay (EMSA) showed neither metal-binding motifs nor redox switches in BlmR. In order to elucidate the regulatory mechanism, a model of BlmR was constructed by homology modeling and protein-protein docking. The BlmR-DNA complex was generated by protein-DNA docking with the assistance of site-directed mutagenesis and molecular dynamic (MD) simulation, which directly revealed several key amino acid residues needed for the maintenance and stabilization of the interface between BlmR and target DNA. The interface information could provide the configuration reference and seek the potential effectors that could interact with BlmR, thereby extending the regulation role of ArsR/SmtB family members on the improvement of antibiotic production.


Assuntos
Antibióticos Antineoplásicos/biossíntese , Vias Biossintéticas/genética , Bleomicina/biossíntese , Regulação Bacteriana da Expressão Gênica , Proteínas Repressoras/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , DNA Bacteriano/metabolismo , Deleção de Genes , Expressão Gênica , Perfilação da Expressão Gênica , Simulação de Acoplamento Molecular , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética
13.
Int J Mol Sci ; 19(8)2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30042347

RESUMO

Continuous cropping in soybean is increasingly practiced in Heilongjiang Province, leading to substantial yield reductions and quality degradation. Arbuscular mycorrhizal fungi (AMF) are soil microorganisms that form mutualistic interactions with plant roots and can restore the plant rhizosphere microenvironment. In this study, two soybean lines (HN48 and HN66) were chosen as experimental materials, which were planted in different years of continuous cropping soybean soils and were inoculated or not with Funneliformis mosseae in potted-experiments. Ultimately, analysis of root tissue metabolome and root exudates, soil physicochemical properties, plant biomass, as well as rhizosphere soil properties in different experimental treatments, inoculated or not with F. mosseae, was performed. Experimental results showed that: (a) The disease index of soybean root rot was significantly lower in the treatment group than in the control group, and there were differences in disease index and the resistance effect of F. mosseae between the two cultivars; (b) compared with the control, the root tissue metabolome and root exudates remained unchanged, but there were changes in the relative amounts in the treatment group, and the abundant metabolites differed by soybean cultivar; (c) soybean biomass was significantly higher in the treatment group than in the control group, and the effect of F. mosseae on biomass differed with respect to the soybean cultivar; and (d) there were differences in the physiochemical indexes of soybean rhizosphere soil between the treatment and control groups, and the repairing effect of F. mosseae differed between the two cultivars. Therefore, F. mosseae can increase the biomass of continuously cropped soybean, improve the physicochemical properties of the rhizosphere soil, regulate the root metabolite profiles, and alleviate barriers to continuous cropping in potted-experiments of soybean.


Assuntos
Glomeromycota/metabolismo , Glycine max/microbiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Rizosfera , Agricultura , Fenômenos Químicos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Glomeromycota/crescimento & desenvolvimento , Metaboloma , Exsudatos de Plantas/análise , Solo/química , Microbiologia do Solo , Glycine max/crescimento & desenvolvimento
14.
Plants (Basel) ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38999590

RESUMO

Due to global warming and increased human activity, the wild population of Thuja koraiensis Nakai (T. koraiensis) has dropped, placing it in danger. An understanding of the response of T. koraiensis to climate change and the determination of priority conservation areas are tremendously critical for proper conservation. Using sixty-nine T. koraiensis distribution points and seven environmental factors, the Maxent model was used to predict potentially suitable areas and spatial variation patterns of T. koraiensis and the Marxan conservation planning model was used to evaluate conservation gap areas. Research shows that the dominant environmental factors affecting the distribution of potentially suitable areas for T. koraiensis included elevation, precipitation of the driest month, isothermality and precipitation of the wettest quarter. Under the current climatic conditions, highly suitable areas for T. koraiensis are mainly distributed in the Changbai Mountains within Samjiyon County and Baishan City, the Hamgyong Mountains within the western part of Hamgyong-Bukto Province, and the T'aeback-Sanmaek Mountains within Gangwon-do, Kumgangsan Special Administrative Region and Kangwon-do. Under future climate conditions, suitable areas for T. koraiensis show a decreasing trend, and the suitable area will be reduced to higher elevations, and the Hamgyong Mountains may become a refuge. Based on GAP analysis, 69.69% of the priority conservation areas of T. koraiensis are located outside of the nature reserve, and these conservation gap areas are primarily in the southern part of the Changbai Mountains and Kangwon-do.

15.
Foods ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611355

RESUMO

This study prepared a novel ß-carotene colorant lake using calcium carbonate (CaCO3) and investigated the lake formation process and its basic characteristics. Kinetic adsorption analysis confirmed that medium pH (9.3) and medium temperature (40 °C) were more suitable for lake preparation, while desorption occurred, possibly due to crystalline transformation of CaCO3. The isothermal analysis and model fitting results suggested that the ß-carotene and CaCO3 particles combined via a monolayer adsorption process driven by physical force. Electrostatic attraction likely participated in the process due to the net negative surface charges of ß-carotene dispersion and positively charged groups on the CaCO3 particle surfaces. Ethanol, ultrasonic treatment, and drying method significantly influenced the immobilization efficiency (IE) of ß-carotene in the lake and light stability of the lake, without affecting its crystal form. The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) curves confirmed absorption of ß-carotene onto CaCO3. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses indicated no obvious chemical bonds between ß-carotene and CaCO3. Energy-dispersive spectroscopy (EDS) confirmed the presence of ß-carotene on surfaces but not in the interior of the CaCO3 particles. The adsorption of ß-carotene by calcium carbonate was further confirmed to be a physical adsorption on surface.

16.
IEEE Trans Med Imaging ; PP2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869996

RESUMO

To obtain high-quality positron emission tomography (PET) images while minimizing radiation exposure, numerous methods have been dedicated to acquiring standard-count PET (SPET) from low-count PET (LPET). However, current methods have failed to take full advantage of the different emphasized information from multiple domains, i.e., the sinogram, image, and frequency domains, resulting in the loss of crucial details. Meanwhile, they overlook the unique inner-structure of the sinograms, thereby failing to fully capture its structural characteristics and relationships. To alleviate these problems, in this paper, we proposed a prior knowledge-guided transformer-GAN that unites triple domains of sinogram, image, and frequency to directly reconstruct SPET images from LPET sinograms, namely PK-TriDo. Our PK-TriDo consists of a Sinogram Inner-Structure-based Denoising Transformer (SISD-Former) to denoise the input LPET sinogram, a Frequency-adapted Image Reconstruction Transformer (FaIR-Former) to reconstruct high-quality SPET images from the denoised sinograms guided by the image domain prior knowledge, and an Adversarial Network (AdvNet) to further enhance the reconstruction quality via adversarial training. Specifically tailored for the PET imaging mechanism, we injected a sinogram embedding module that partitions the sinograms by rows and columns to obtain 1D sequences of angles and distances to faithfully preserve the inner-structure of the sinograms. Moreover, to mitigate high-frequency distortions and enhance reconstruction details, we integrated global-local frequency parsers (GLFPs) into FaIR-Former to calibrate the distributions and proportions of different frequency bands, thus compelling the network to preserve high-frequency details. Evaluations on three datasets with different dose levels and imaging scenarios demonstrated that our PK-TriDo outperforms the state-of-the-art methods.

17.
Stem Cell Res ; 73: 103255, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37992565

RESUMO

NSD2 is a histone methyltransferase (HMT) and is involved in the epigenetic regulation of hematopoiesis and hematological cancers. To understand and illustrate the precise roles of NSD2 in hematopoietic development, here we constructed a human embryonic stem cell (hESC) line with knockout of NSD2 using CRISPR/Cas9-mediated gene targeting. The cell line maintained typical stem cell morphology and normal karyotype. Furthermore, the pluripotency of the cell line was evidenced by high expression level of pluripotency genes and differentiation potential into three germ layers. The cell line provides a good model for studying roles of NSD2 in embryonic development, especially hematopoiesis.


Assuntos
Células-Tronco Embrionárias Humanas , Humanos , Células-Tronco Embrionárias Humanas/metabolismo , Sistemas CRISPR-Cas/genética , Epigênese Genética , Células-Tronco Embrionárias/metabolismo , Linhagem Celular
18.
Environ Pollut ; 317: 120721, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36436663

RESUMO

Studies analyzing the in vitro bioaccessibility (BAc) of heavy metals in biochar-amended soils are currently lacking. The present study aimed to assess the metal BAc in Cd- and Pb-spiked acidic Ultisol samples treated individually with 2% (w/w) maize, rice, wheat, soybean, and pea straw-derived biochar. The results indicate that the Cd-BAc simulated in gastric phase (GP) decreased from 78.4% to 66.5-72.3% and the Pb-BAC decreased from 74.3% to 67.2-69.2%; however, the Cd-BAc in the intestinal phase (IP) decreased from 35.6% to 27.9-33.5% and the Pb-BAc decreased from 34.7% to 29.7-32.9% after 120 d of incubation with biochar application compared to the un-amended Ultisol. The Cd- and Pb-BAc in both GP and IP were significantly negatively correlated with soil pH, CEC, and organic carbon (P < 0.05), which increased after biochar application. The soybean straw-derived biochar amendment has the greatest potential to decrease the BAc of Cd and Pb in the GP and IP, owing to the highest level of CEC, SOC, TC and TN among all soil samples. Moreover, the BAc was positively correlated with the exchangeable, and exchangeable + carbonate-bound Cd and Pb fractions (P < 0.05), indicating these fractions had a dominant influence on the BAc of cationic heavy metals. Therefore, crop straw-derived biochar amendment can decrease the BAc of Cd and Pb in acidic Ultisol, and thus mitigate the health risks posed by these metals from incidental ingestion.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Cádmio/análise , Chumbo , Poluentes do Solo/análise , Metais Pesados/análise , Carvão Vegetal , Solo , Ácidos
19.
Int J Neural Syst ; 33(11): 2350057, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37771298

RESUMO

Radiotherapy is one of the leading treatments for cancer. To accelerate the implementation of radiotherapy in clinic, various deep learning-based methods have been developed for automatic dose prediction. However, the effectiveness of these methods heavily relies on the availability of a substantial amount of data with labels, i.e. the dose distribution maps, which cost dosimetrists considerable time and effort to acquire. For cancers of low-incidence, such as cervical cancer, it is often a luxury to collect an adequate amount of labeled data to train a well-performing deep learning (DL) model. To mitigate this problem, in this paper, we resort to the unsupervised domain adaptation (UDA) strategy to achieve accurate dose prediction for cervical cancer (target domain) by leveraging the well-labeled high-incidence rectal cancer (source domain). Specifically, we introduce the cross-attention mechanism to learn the domain-invariant features and develop a cross-attention transformer-based encoder to align the two different cancer domains. Meanwhile, to preserve the target-specific knowledge, we employ multiple domain classifiers to enforce the network to extract more discriminative target features. In addition, we employ two independent convolutional neural network (CNN) decoders to compensate for the lack of spatial inductive bias in the pure transformer and generate accurate dose maps for both domains. Furthermore, to enhance the performance, two additional losses, i.e. a knowledge distillation loss (KDL) and a domain classification loss (DCL), are incorporated to transfer the domain-invariant features while preserving domain-specific information. Experimental results on a rectal cancer dataset and a cervical cancer dataset have demonstrated that our method achieves the best quantitative results with [Formula: see text], [Formula: see text], and HI of 1.446, 1.231, and 0.082, respectively, and outperforms other methods in terms of qualitative assessment.


Assuntos
Neoplasias Retais , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/radioterapia , Redes Neurais de Computação
20.
Front Microbiol ; 14: 1207196, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396390

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants with major risks to human health. Biological degradation is environmentally friendly and the most appealing remediation method for a wide range of persistent pollutants. Meanwhile, due to the large microbial strain collection and multiple metabolic pathways, PAH degradation via an artificial mixed microbial system (MMS) has emerged and is regarded as a promising bioremediation approach. The artificial MMS construction by simplifying the community structure, clarifying the labor division, and streamlining the metabolic flux has shown tremendous efficiency. This review describes the construction principles, influencing factors, and enhancement strategies of artificial MMS for PAH degradation. In addition, we identify the challenges and future opportunities for the development of MMS toward new or upgraded high-performance applications.

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