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1.
Nat Chem Biol ; 18(11): 1214-1223, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35982226

RESUMO

The E3 ligase TRIM7 has emerged as a critical player in viral infection and pathogenesis. However, the mechanism governing the TRIM7-substrate association remains to be defined. Here we report the crystal structures of TRIM7 in complex with 2C peptides of human enterovirus. Structure-guided studies reveal the C-terminal glutamine residue of 2C as the primary determinant for TRIM7 binding. Leveraged by this finding, we identify norovirus and SARS-CoV-2 proteins, and physiological proteins, as new TRIM7 substrates. Crystal structures of TRIM7 in complex with multiple peptides derived from SARS-CoV-2 proteins display the same glutamine-end recognition mode. Furthermore, TRIM7 could trigger the ubiquitination and degradation of these substrates, possibly representing a new Gln/C-degron pathway. Together, these findings unveil a common recognition mode by TRIM7, providing the foundation for further mechanistic characterization of antiviral and cellular functions of TRIM7.


Assuntos
COVID-19 , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Glutamina/metabolismo , SARS-CoV-2 , Ubiquitinação , Antivirais , Proteínas com Motivo Tripartido/metabolismo
2.
Nucleic Acids Res ; 50(22): 12913-12923, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36484100

RESUMO

The type III-E CRISPR-Cas systems are newly identified adaptive immune systems in prokaryotes that use a single Cas7-11 protein to specifically cleave target RNA. Cas7-11 could associate with Csx29, a putative caspase-like protein encoded by the gene frequently found in the type III-E loci, suggesting a functional linkage between the RNase and protease activities in type III-E systems. Here, we demonstrated that target RNA recognition would stimulate the proteolytic activity of Csx29, and protein Csx30 is the endogenous substrate. More interestingly, while the cognate target RNA recognition would activate Csx29, non-cognate target RNA with the complementary 3' anti-tag sequence inhibits the enzymatic activity. Csx30 could bind to the sigma factor RpoE, which may initiate the stress response after proteolytic cleavage. Combined with biochemical and structural studies, we have elucidated the mechanisms underlying the target RNA-guided proteolytic activity of Csx29. Our work will guide further developments leveraging this simple RNA targeting system for RNA and protein-related applications.


Assuntos
Proteínas Associadas a CRISPR , RNA , RNA/genética , Sistemas CRISPR-Cas , Endorribonucleases/metabolismo , Ribonucleases/metabolismo , Peptídeo Hidrolases/genética , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo
3.
Genet Mol Biol ; 45(2): e20210237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275159

RESUMO

Transfection efficiency was estimated to optimize the conditions for RNA interference (RNAi), including transfection time, validity, and nucleic acid concentration and type, using the EZ Trans Cell Reagent, a cationic polymer. An shRNA against GFP was designed and transfected into cells using the EZ transfection reagent. The shRNA significantly decreased the expression of GFP. In addition, pre-diluted transfection reagent at room temperature and small nucleic acids increased the transfection efficiency, which peaked at 24 h. Compared with circular nucleic acids, linear nucleic acids showed higher transfection efficiency and a higher genome integration rate. We optimized cationic polymer-mediated RNAi conditions, and our data will be useful for future RNAi studies.

4.
Anal Biochem ; 582: 113355, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276651

RESUMO

Quantitative analysis of glycosphingolipids (GSLs) has been hindered by the lack of chromogenic groups for spectral detection or active functional groups for specific derivatization. In this study, a highly sensitive method based on ozonolysis-induced release and isotopic Girard's reagent P labeling of GSL glycans coupled with mass spectrometric detection for the quantification of animal tissue GSLs is developed. First, different approaches for the release of glycans from GSLs were compared with each other and the ozonolysis-based method was found to have the highest glycan yield under relative mild reaction conditions. Then a relative quantification method of ozonolysis-released GSL glycans based on stable isotope labeling using nondeuterated (d0-) and 2,3,4,5,6-pentadeuterated (d5-) Girard's reagent P (GP) was established, and its good linearity, accuracy and reproducibility were statistically verified. Finally, the new method was successfully applied to revealing the difference between porcine brain and liver as well as between the brain of normal and aging rats in GSL glycome by online hydrophilic interaction liquid chromatography coupling with ultraviolet detection and tandem mass spectrometry (HILIC-UV-MS/MS). This novel method is versatile and sensitive, enabling accurate quantitative analysis of tissue GSLs and showing great significance for glycomic studies.


Assuntos
Betaína/análogos & derivados , Química Encefálica , Glicoesfingolipídeos/análise , Fígado/química , Polissacarídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Betaína/química , Encéfalo/metabolismo , Marcação por Isótopo/métodos , Fígado/metabolismo , Ratos , Ratos Sprague-Dawley , Suínos
5.
BMC Genomics ; 19(1): 68, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29357812

RESUMO

BACKGROUND: Sweetpotato whitefly, Bemisia tabaci MED/Q and MEAM1/B, are two economically important invasive species that cause considerable damages to agriculture crops through direct feeding and indirect vectoring of plant pathogens. Recently, a draft genome of B. tabaci MED/Q has been assembled. In this study, we focus on the genomic comparison between MED/Q and MEAM1/B, with a special interest in MED/Q's genomic signatures that may contribute to the highly invasive nature of this emerging insect pest. RESULTS: The genomes of both species share similarity in syntenic blocks, but have significant divergence in the gene coding sequence. Expansion of cytochrome P450 monooxygenases and UDP glycosyltransferases in MED/Q and MEAM1/B genome is functionally validated for mediating insecticide resistance in MED/Q using in vivo RNAi. The amino acid biosynthesis pathways in MED/Q genome are partitioned among the host and endosymbiont genomes in a manner distinct from other hemipterans. Evidence of horizontal gene transfer to the host genome may explain their obligate relationship. Putative loss-of-function in the immune deficiency-signaling pathway due to the gene loss is a shared ancestral trait among hemipteran insects. CONCLUSIONS: The expansion of detoxification genes families, such as P450s, may contribute to the development of insecticide resistance traits and a broad host range in MED/Q and MEAM1/B, and facilitate species' invasions into intensively managed cropping systems. Numerical and compositional changes in multiple gene families (gene loss and gene gain) in the MED/Q genome sets a foundation for future hypothesis testing that will advance our understanding of adaptation, viral transmission, symbiosis, and plant-insect-pathogen tritrophic interactions.


Assuntos
Genoma de Inseto , Hemípteros/classificação , Hemípteros/genética , Proteínas de Insetos/genética , Resistência a Inseticidas , Animais , Produtos Agrícolas/parasitologia , Sistema Enzimático do Citocromo P-450/genética , Glucuronosiltransferase/genética , Especificidade de Hospedeiro , Família Multigênica , Filogenia , Simbiose , Transcriptoma
6.
Anal Biochem ; 549: 1-11, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29524379

RESUMO

Sensitive analysis of glycans by liquid chromatography/mass spectrometry is significantly hampered by the lack of chromogenic or fluorescent groups on the glycan structures, as well as, their poor ionization properties. In the present, a heterobifunctional chromogenic reagent 3-amino-1-phenyl-2-pyrazoline-5-ketone (PAP) bearing amino and active methylene groups, which readily reacts with reducing glycans, was used for detection of the pre-column-labeled glycans via high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS). The PAP derivatives with active methylene and amino groups were obtained via reductive amination in acidic medium and condensation of an active PAP methylene group with the reducing end of glycans in alkaline medium, respectively, and the PAP derivatives could be further functionalized, e.g., via glycan microarray preparation. The conditions for the two reaction modes were optimized, the HPLC separation method of PAP derivatives was investigated, and the PAP derivatives of some glycans derived from biological samples were obtained and analyzed by ESI-MS and LC-MS. Using this new reagent, reducing glycans can be selectively derivatized by different reaction mechanisms, having great importance for functional glycomics studies.


Assuntos
Polissacarídeos/análise , Pirazolonas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida/métodos , Humanos
7.
Pestic Biochem Physiol ; 134: 73-78, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27914542

RESUMO

The whitefly, Bemisia tabaci, has developed a high level of resistance to thiamethoxam, a second generation neonicotinoid insecticide that has been widely used to control this pest. In this study, we assessed the level of cross-resistance, the activities of detoxifying enzymes, and the expression profiles of 23 glutathione S-transferase (GST) genes in a thiamethoxam-resistant ant and -susceptible strain of Bemisia tabaci Q. The thiamethoxam-resistant strain showed a moderate level of cross-resistance to another nicotinoid insecticide imidacloprid, a low level of cross-resistance to acetamiprid and nitenpyram, and no significant cross-resistance to abamectin and bifenthrin. Among detoxifying enzymes, only GSTs had significantly higher activity in the resistant strain than in the susceptible strain. Seven of 23 GST genes were over-expressed in the resistant strain relative to the susceptible strain. Using the technology of RNA interference to knockdown a GST gene (GST14), the results showed that silencing GST14 increased the mortality of whiteflies to thiamethoxam in Bemisia tabaci.


Assuntos
Glutationa Transferase/genética , Hemípteros , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Oxazinas/toxicidade , Tiazóis/toxicidade , Animais , Carboxilesterase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Expressão Gênica , Glutationa Transferase/metabolismo , Hemípteros/efeitos dos fármacos , Hemípteros/enzimologia , Hemípteros/genética , Proteínas de Insetos/metabolismo , Masculino , Neonicotinoides , Interferência de RNA , Tiametoxam
8.
Artigo em Zh | MEDLINE | ID: mdl-26887262

RESUMO

OBJECTIVE: To analyze the opioid binding protein/cell adhesion molecule-like (OPCML) methylation status at different stages of malignant transformation of human bronchial epithelial (16HBE) cells induced by Glycidyl Methacrylate (GMA) and to explore the effect of OPCML methylation in the process of malignant transformation. METHODS: Cells were harvested at different stages (the 10th generation, the 20th generation and the 30th generation). To verify the Methylation chip result of OPCML methylation status in the process of malignant transformation, we detected it by methylation-specific-PCR (MSP); Real-time fluorescence Quantitative PCR (qPCR) were applied to measure the gene expression levels of OPCML at different transformed stage, and compared with the control groups (treated with DMSO). RESULTS: Based on the result of methylation chip, the gene of OPCML methylation occurred in all stages, which was consistent to the result of MSP; qPCR showed that the levels of gene expression decreased in the 20th generation and 30th generation. CONCLUSION: Methylation status of OPCML gene promoter could be considered as a stable and specific biomarker in the transformation process.


Assuntos
Moléculas de Adesão Celular/metabolismo , Transformação Celular Neoplásica/induzido quimicamente , Células Epiteliais/citologia , Compostos de Epóxi/efeitos adversos , Genes Supressores de Tumor , Metacrilatos/efeitos adversos , Células Cultivadas , Metilação de DNA , Células Epiteliais/efeitos dos fármacos , Proteínas Ligadas por GPI/metabolismo , Humanos , Regiões Promotoras Genéticas
9.
Artigo em Zh | MEDLINE | ID: mdl-25169236

RESUMO

OBJECTIVE: To develop a method for determination of 2, 4-dichlorophenoxyacetic acid (2, 4-D) in the air of workplace by high-performance liquid chromatography. METHODS: 2, 4-D was collected by ultrafine glass filters, desorbed by methanol, separated by a C18 column, and detected by a UV detector. Identification and quantification of 2, 4-D were performed by retention time and peak areas, respectively. RESULTS: The linear range of the test was 2∼200 µg/ml; the elution efficiency was 94.6%- 95.9%; the limit of detection (S/N = 3) was 0.034 µg/ml (injection volume of 20 µl eluant); the lower limit of quantification (S/N = 10) was 0.11 µg/ml; the minimum detectable concentration was 0.011 mg/m(3); the minimum quantifiable concentration was 0.037 mg/m(3) (with sampled air volume of 45 L). CONCLUSION: This method is convenient and simple in sample collection and preparation, and satisfies all methodological requirements. Therefore, this method is useful for the determination of 2, 4-D in the air of workplace.


Assuntos
Ácido 2,4-Diclorofenoxiacético/análise , Poluentes Ocupacionais do Ar/análise , Ar/análise , Cromatografia Líquida de Alta Pressão/métodos , Local de Trabalho
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 355-364, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38660836

RESUMO

OBJECTIVE: To investigate the relationship between IGF2BP3 gene expression and prognosis in patients with acute myeloid leukemia (AML). METHODS: High throughput transcriptome sequencing was performed on bone marrow primary leukemia cells from 27 patients with AML in our center, the relationship between IGF2BP3 expression levels and clinical characteristics were analyzed and verify the samples from patients with newly treated AML and refractory AML. The expression level of IGF2BP3 gene were analyzed in 20 healthy subjects and 26 patients with AML. The expression of IGF2BP3 in two anthracycline-resistant cell lines (HL60/ADR, K562/ADR) was detected by RT-qPCR and Western blot, and the expression difference of IGF2BP3 was compared with that in sensitive cells (HL60, K562). The relationship between the expression level of IGF2BP3 in patients with AML and prognostic were analyzed through data analysis of 746 patients with AML, and the prognostic value of IGF2BP3 in AML was analyzed by multivariate Cox regression analysis. RESULTS: In the bone marrow primary leukemia cells of 27 AML patients in our center, the expression level of IGF2BP3 in patients with refractory AML was significantly higher than that in chemotherapy sensitive patients (P =0.0343). The expression of IGF2BP3 in leukemia patients with extramedullary infiltration (EMI) was significantly higher than that in AML patients without extramedullary infiltration (P =0.0049). Compared with healthy subjects (n=20), IGF2BP3 expression in AML patients (n=26) was higher (P =0.0009). The expression of IGF2BP3 mRNA in the anthracycline resistant cell lines (HL60/ADR, K562/ADR) was significantly higher than that in the sensitive cell lines (K562/ADR vs K562,P =0.0430; HL60/ADR vs HL60, P =0.7369). Western blot results showed that the expression of IGF2BP3 protein in mycin resistant cells was significantly higher than that in sensitive cells (P < 0.001). qPCR results showed that the expression level of IGF2BP3 mRNA in refractory AML patients was significantly higher than that in patients with chemotherapy sensitive (P =0.002). High expression of IGF2BP3 was associated with poor prognosis in AML (P < 0.05) in 3 large sample cohorts of AML patients. Univariate and multivariate prognostic analyses demonstrated that high expression of IGF2BP3 was significantly associated with shorter event-free survival (EFS, HR=1.887, P =0.024) and overall survival (OS, HR=1.619, P =0.016). CONCLUSION: The high expression of IGF2BP3 gene may be an important factor in the poor prognosis of AML, suggesting that IGF2BP3 gene may be a new molecular marker for the clinical prognosis evaluation and treatment strategy of AML.


Assuntos
Leucemia Mieloide Aguda , Proteínas de Ligação a RNA , Humanos , Leucemia Mieloide Aguda/genética , Prognóstico , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Expressão Gênica , Células HL-60 , Células K562 , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(1): 90-95, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38387905

RESUMO

OBJECTIVE: To investigate the efficacy and safety of Venetoclax combined with CACAG regimen in treatment of patients with refractory/relapse acute myeloid leukemia(R/R AML). METHODS: The study was a singlecenter prospective clinical trial. The enrolled patients met the criteria for R/R AML. Treatment included Azacidine(75 mg/m2,d 1-7), Ara-C (75-100 mg/m2, q12h, d 1-5), Aclacinomycin(20 mg d1,d3,d5), Chidamide(30 mg d1,d4), Venetoclax(100 mg d1, 200 mg d2, 400 mg d3-d14, in combination with Triazole Drug, reduced to 100 mg/d), and granulocyte colony-stimulating factor (300 µg /d until neutrophil recovery). The primary endpoint of observation was overall response rate after 1 course of treatment. RESULTS: A total of 19 patients were enrolled from January 2022 to April 2023. After 1 course of treatmen, the overall response rate was 81.3%(13/16), the CR rate was 68.8%(11/16), and the PR was 12.5%(2/16). Among the 11 patients who got CR/CRi, 8 cases achieved CRm (minimal residual disease negative CR) and 3 cases did not. As of March 27, 2023, the median follow-up time was 111(19-406) days. The six-month overall survival and progression-free survival rates were both 55.7%, the 1-year overall survival and progression-free survival rates were 46.4% and 47.7%, respectively. In addition, compared with the non-CRm group, CRm patients had a better PFS (377 days vs 111 days, P =0.046). Treatment-related adverse events were mainly 3-4 degrees of bone marrow suppression, complicated by various degrees of infection(n=12), hypokalemia(n=12) and hypocalcemia (n=10) and elevated liver enzymes (n=8), of which 3/4 degrees accounted for 47.4%(9/19). CONCLUSION: The Venetoclax combined with CACAG regimen is an effective salvage therapy for patients with R/R AML, with high remission rate and safety profile.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Leucemia Mieloide Aguda , Sulfonamidas , Humanos , Estudos Prospectivos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/etiologia , Citarabina , Recidiva , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
12.
Artigo em Inglês | MEDLINE | ID: mdl-36767800

RESUMO

It is important to explore characteristics of dissolved organic matter (DOM) in the riverine system due to its critical role in the carbon cycle. This study investigated the distribution characteristics and sources of DOM based on excitation emission matrix three-dimensional fluorescence technology and parallel factor (EEM-PARAFAC) analysis at two rivers in northern China strongly impacted by human activities. The results show that the fluorescence intensity of terrestrial humic-like substances increased during summer in Haihe River. The intensity was significantly higher than in spring due to terrestrial detritus from runoff conveyance. The fluorescence intensity of protein-like substances in spring was the highest and decreased in summer. This feature of DOM in the Duliujian River was related to the increase in precipitation and surface runoff in the wet season and the rapid degradation of mixed DOM in the dry season. An analysis of HIX, BIX and FI showed a low degree of DOM humification and more endogenous contributions from microbial and phytoplankton degradation. Seasonal variations of dissolved organic carbon (DOC) and chromophoric DOM (CDOM, a335, thereinto C1) suggest that chromophores, particularly terrestrial substances, regulate the temporal patterns of DOM in the two rivers. Combined with the analysis of the proportion of land use types in riparian buffers, tillage had a great impact on DOM content and hydrophobicity in Haihe River watershed. Domestic wastewater and industrial sewage discharge contribute more DOM to Duliujian River watershed, which was indicated by more abundant protein-like components (212.17 ± 94.63 QSU in Duliujian River;186.59 ± 238.72 QSU in Haihe River). This study highlights that different land use types resulted in distinctive sources and seasonal dynamics of DOM in rivers. Meanwhile, it should be considered that the estimation of carbon cycling should involve monitoring and evaluating anthropogenic inputs into rivers.


Assuntos
Matéria Orgânica Dissolvida , Rios , Humanos , Águas Residuárias , Esgotos , China , Substâncias Húmicas/análise , Espectrometria de Fluorescência
13.
Front Oncol ; 13: 1144403, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064135

RESUMO

Background: Acute myeloid leukemia (AML) is a heterogeneous hematopoietic malignancy. Patient prognosis cannot be accurately assessed in National Comprehensive Cancer Network (NCCN) risk stratification subgroups based on the current criteria. This study aimed to develop a novel prognostic score model for the quantitative prediction of prognosis in AML. Results: We developed a prognostic risk scoring model of AML using differentially expressed genes to predict prognosis in patients with AML. Furthermore, we evaluated the effectiveness and clinical significance of this prognostic model in 4 AML cohorts and 905 patients with AML. A prognostic risk scoring model of AML containing eight prognosis-related genes was constructed using a multivariate Cox regression model. The model had a higher predictive value for the prognosis of AML in the training and validation sets. In addition, patients with lower scores had significantly better overall survival (OS) and even-free survival (EFS) than those with higher scores among patients with intermediate-risk AML according to the NCCN guidelines, indicating that the model could be used to further predict the prognosis of the intermediate-risk AML populations. Similarly, patients with high scores had remarkably poor OS and EFS in the normal-karyotype populations, indicating that the scoring model had an excellent predictive performance for patients with AML having normal karyotype. Conclusions: Our study provided an individualized prognostic risk score model that could predict the prognosis of patients with AML.

14.
Cell Res ; 33(9): 699-711, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37311833

RESUMO

Nicotinamide adenine dinucleotide (NAD+) is a central metabolite in cellular processes. Depletion of NAD+ has been demonstrated to be a prevalent theme in both prokaryotic and eukaryotic immune responses. Short prokaryotic Argonaute proteins (Agos) are associated with NADase domain-containing proteins (TIR-APAZ or SIR2-APAZ) encoded in the same operon. They confer immunity against mobile genetic elements, such as bacteriophages and plasmids, by inducing NAD+ depletion upon recognition of target nucleic acids. However, the molecular mechanisms underlying the activation of such prokaryotic NADase/Ago immune systems remain unknown. Here, we report multiple cryo-EM structures of NADase/Ago complexes from two distinct systems (TIR-APAZ/Ago and SIR2-APAZ/Ago). Target DNA binding triggers tetramerization of the TIR-APAZ/Ago complex by a cooperative self-assembly mechanism, while the heterodimeric SIR2-APAZ/Ago complex does not assemble into higher-order oligomers upon target DNA binding. However, the NADase activities of these two systems are unleashed via a similar closed-to-open transition of the catalytic pocket, albeit by different mechanisms. Furthermore, a functionally conserved sensor loop is employed to inspect the guide RNA-target DNA base pairing and facilitate the conformational rearrangement of Ago proteins required for the activation of these two systems. Overall, our study reveals the mechanistic diversity and similarity of Ago protein-associated NADase systems in prokaryotic immune response.


Assuntos
Proteínas Argonautas , NAD+ Nucleosidase , Proteínas Argonautas/metabolismo , NAD+ Nucleosidase/metabolismo , NAD/metabolismo , Bactérias/genética , DNA
15.
Front Psychol ; 13: 822609, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465578

RESUMO

In recent years, there are many reasons for the frequent safety accidents in the construction field. The most controversial and typical one that firmly correlated with China's national condition is the low-price bid winning and the general subcontracting management, which probably have a great impact on the unsafe behavior intention of workers on the construction site. In order to figure out their internal relation, a quantitative statistical analysis of the unsafe behavior intentions of construction workers in the Beijing area was conducted through the on-site questionnaire considering three main variables, namely, general subcontract management, reasonable low-cost bid winning, and construction experiences. Meanwhile, the correlation, regression, and mediating effects of different influencing factors were analyzed through a regressive model to quantify the impact of each variable on the unsafe behavior intention of construction workers. The results showed that the influence of low-price bid winning on the unsafe behavior intention of on-site workers is faint. This is mainly because, in the case of labor buyer's market, the actual salary of workers is not relevant to whether the project is awarded at a low price. However, the general subcontracting management has a great impact on the unsafe behavior intention of on-site workers. At the same time, low-price bid winning also indirectly affects the strength of general subcontracting safety management, which has an indirect impact on the unsafe behavior intention of on-site workers. Generally, it is of greater significance to enhance the strength of the general subcontracting management and to formulate relevant regulations to guarantee the safety of construction workers.

16.
Sci Data ; 9(1): 176, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440581

RESUMO

Human Footprint, the pressure imposed on the eco-environment by changing ecological processes and natural landscapes, is raising worldwide concerns on biodiversity and ecological conservation. Due to the lack of spatiotemporally consistent datasets of Human Footprint over a long temporal span, many relevant studies on this topic have been limited. Here, we mapped the annual dynamics of the global Human Footprint from 2000 to 2018 using eight variables that reflect different aspects of human pressures. The accuracy assessment revealed a good agreement between our mapped results and the previously developed datasets in different years. We found more than two million km2 of wilderness (i.e., regions with Human Footprint values below one) were lost over the past two decades. The biome dominated by mangroves experienced the most significant loss (i.e., above 5%) of wilderness, likely attributed to intensified human activities in coastal areas. The derived annual and spatiotemporally consistent global Human Footprint can be a fundamental dataset for many relevant studies about human activities and natural resources.

17.
Front Genet ; 13: 833694, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571033

RESUMO

Acute myeloid leukemia (AML) is one of the most aggressive hematopoietic malignancies. Patients still suffer from refractory/relapsed disease after anthracycline-based therapy, which leads to a poor prognosis. N6-Methyladenosine (m6A) is the most abundant post-transcriptional modification in eukaryotes, the imbalance of which is reported to be associated with various pathological processes, including drug resistance. However, the relationship between m6A modification and drug resistance has not been well defined in AML. In this study, we analyzed the sequencing data of HL60 and its Adriamycin-resistant cell line HL60/ADR. We found a total of 40,550 m6A-methylated peaks, representing 15,640 genes in HL60, and 38,834 m6A-methylated peaks, representing 15,285 genes in HL60/ADR. KEGG pathway analysis showed that pathways were enriched in the FoxO signaling pathway, p53 signaling pathway, and Notch signaling pathway. MeRIP-seq results showed that the fold enrichment of the global m6A level in HL60/ADR was higher than that in HL60, and dot blot assay results indicated that the global m6A level was elevated in HL60/ADR cells compared with that in HL60 cells. Further analysis revealed that the expression level of METTL3 was elevated in HL60/ADR cells compared with that in HL60 cells. After a combined treatment of STM2457 (an inhibitor of METTL3) and Adriamycin, the proliferation of HL60/ADR was inhibited. Thus, we hypothesized that the abnormality of m6A modification played an important role in Adriamycin-resistant AML.

18.
Nat Microbiol ; 7(12): 2078-2088, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36302881

RESUMO

The type III-E CRISPR-Cas system uses a single multidomain effector called Cas7-11 (also named gRAMP) to cleave RNA and associate with a caspase-like protease Csx29, showing promising potential for RNA-targeting applications. The structural and molecular mechanisms of the type III-E CRISPR-Cas system remain poorly understood. Here we report four cryo-electron microscopy structures of Cas7-11 at different functional states. Cas7-11 has four Cas7-like domains, which assemble into a helical filament to accommodate CRISPR RNA (crRNA), and a Cas11-like domain facilitating crRNA-target RNA duplex formation. The Cas7.1 domain is critical for crRNA maturation, whereas Cas7.2 and Cas7.3 are responsible for target RNA cleavage. Target RNA binding induces the structural arrangements of Csx29, potentially exposing the catalytic site of Csx29. These results delineate the molecular mechanisms underlying pre-crRNA processing, target RNA recognition and cleavage for Cas7-11, and provide a structural framework to understand the role of Csx29 in type III-E CRISPR system.


Assuntos
Sistemas CRISPR-Cas , Processamento Pós-Transcricional do RNA , Microscopia Crioeletrônica , Domínio Catalítico , RNA
19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(1): 276-285, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35123640

RESUMO

OBJECTIVE: To analyze the kinetic characteristics of lymphocyte subsets and myeloid-derived suppressor cell (MDSC) in patients who newly diagnosed intermediate- to high-risk aGVHD and treated with steroids-ruxolitinib as the first line therapy from a single-arm, open clinical trial (NCT04061876). METHODS: We prospectively observed the efficacy of 23 patients having intermediate- to high-risk aGVHD and treated with steroids-ruxolitinib as the first line therapy. The kinetic characteristics of lymphocyte subsets and MDSC were monitored, and then we compared them in steroids-ruxolitinib group (n=23), free-aGVHD group (n=20) and steroids group (n=23). RESULTS: Of the 23 patients, the CR rate was 78.26% (18/23) on day 28 after first-line treatment with steroids-ruxolitinib. On day 28 after treatment, patients had lower level of CD4+CD29+ T cells (P=0.08) than that of pre-treatment, whereas levels of other lymphocyte subsets in this study were higher than that of pre-treatment; CD4+CD29+ T cells in CR patients decreased, compared with refractory aGVHD patients. On day 28 of treatment, CD8+CD28- T cells (P=0.03) significantly increased in patients with aGVHD than that in patients without aGVHD, so did CD8+CD28- T / CD8+CD28+ T cell ratio (P=0.03). Compared with patients without aGVHD, patients with aGVHD had lower level of G-MDSC, especially on day 14 after allo-HSCT (P=0.04). Compared with pre-treatment, M-MDSC was higher in CR patients on day 3 and 7 post-treatment (P3=0.01, P7=0.03), e-MDSC was higher on day 28 post-treatment (P=0.01). Moreover, compared with CR patients, M-MDSC was lower in refractory aGVHD patients on day 3 post-treatment (P=0.01) and e-MDSC was lower on day 28 post-treatment (P=0.01). Compared with steroids group, MDSC in steroids-ruxolitinib group was higher, with the most significant difference in M-MDSC (P3=0.0351; P7=0.0142; P14=0.0369). CONCLUSION: We found that patients newly diagnosed intermediate- to high-risk aGVHD receiving first-line therapy with steroids-ruxolitinib achieved high response rate. Moreover, the novel first-line therapy has a small impact on the immune reconstitution of patients after allo-HSCT. Elevated MDSC might predict a better response in aGVHD patients receiving this novel first-line therapy. M-MDSC responded earlier to steroids-ruxolitinib than e-MDSC, G-MDSC.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Células Supressoras Mieloides , Humanos , Cinética , Nitrilas , Pirazóis , Pirimidinas , Estudos Retrospectivos , Esteroides
20.
Ann Transplant ; 27: e937356, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36217289

RESUMO

BACKGROUND With the addition of anti-thymocyte globulin (ATG) to GVHD prophylaxis in patients undergoing transplantation of peripheral blood stem cells (PBSCT), the incidence of cGVHD decreases. However, the optimal dose and timing of ATG remain undetermined. MATERIAL AND METHODS In this historical controlled trial, data from 85 patients who had hematological malignancies and underwent matched sibling donor (MSD)-PBSCT were used to analyze the effectiveness of rabbit ATG (rATG) for prophylaxis of GVHD. Forty patients received 5 mg/kg rATG used for days -5 to -2, and 45 patients did not receive ATG. RESULTS All patients had successful engraftment except for 2 in the non-ATG group, who had platelet engraftment failure. The 2-year cumulative incidence of chronic GVHD (cGVHD) in the ATG group versus non-ATG group was 19.3% (95% CI, 8.4-33.6%) versus 61.4% (95% CI, 45.4-73.9%) (P<0.001), and in those with moderate to severe cGVHD it was 11.0% (95% CI, 3.4-23.6%) versus 31.8% (95% CI, 18.8-45.6%) (P=0.029), respectively. The 2-year cumulative incidence of non-relapse mortality and relapse (CIR) were 0% versus 15.5% (95% CI, 6.8-27.5%) (P=0.018), and 53.3% (95% CI, 35.6-68.1%) versus 26.7% (95% CI, 14.9-40.0%) (P=0.019), respectively. No differences were found in other survival outcomes. In the multivariate analysis, ATG was an independent protective factor for moderate to severe cGVHD (HR=0.314, 95% CI, 0.103-0.958, P=0.042), and was an independent poor risk factor for CIR (HR=2.337, 95% CI, 1.133-4.822, P=0.022). CONCLUSIONS ATG in our strategy was effective for prophylaxis of cGVHD, whereas the relapse rate was increased in patients with rATG.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Soro Antilinfocitário/uso terapêutico , Doença Enxerto-Hospedeiro/etiologia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Recidiva Local de Neoplasia , Estudos Retrospectivos , Irmãos , Condicionamento Pré-Transplante/métodos
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