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1.
Eur Radiol ; 34(1): 662-672, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37535155

RESUMO

OBJECTIVES: To construct a machine learning model for differentiating Parkinson's disease (PD) and multiple system atrophy (MSA) by using multimodal PET/MRI radiomics and clinical characteristics. METHODS: One hundred and nineteen patients (81 with PD and 38 with MSA) underwent brain PET/CT and MRI to obtain metabolic images ([18F]FDG, [11C]CFT PET) and structural MRI (T1WI, T2WI, and T2-FLAIR). Image analysis included automatic segmentation on MRI, co-registration of PET images onto the corresponding MRI. Radiomics features were then extracted from the putamina and caudate nuclei and selected to construct predictive models. Moreover, based on PET/MRI radiomics and clinical characteristics, we developed a nomogram. Receiver operating characteristic (ROC) curves were performed to evaluate the performance of the models. Decision curve analysis (DCA) was employed to access the clinical usefulness of the models. RESULTS: The combined PET/MRI radiomics model of five sequences outperformed monomodal radiomics models alone. Further, PET/MRI radiomics-clinical combined model could perfectly distinguish PD from MSA (AUC = 0.993), which outperformed the clinical model (AUC = 0.923, p = 0.028) in training set, with no significant difference in test set (AUC = 0.860 vs 0.917, p = 0.390). However, no significant difference was found between PET/MRI radiomics-clinical model and PET/MRI radiomics model in training (AUC = 0.988, p = 0.276) and test sets (AUC = 0.860 vs 0.845, p = 0.632). DCA demonstrated the highest clinical benefit of PET/MRI radiomics-clinical model. CONCLUSIONS: Our study indicates that multimodal PET/MRI radiomics could achieve promising performance to differentiate between PD and MSA in clinics. CLINICAL RELEVANCE STATEMENT: This study developed an optimal radiomics signature and construct model to distinguish PD from MSA by multimodal PET/MRI imaging methods in clinics for parkinsonian syndromes, which achieved an excellent performance. KEY POINTS: •Multimodal PET/MRI radiomics from putamina and caudate nuclei increase the diagnostic efficiency for distinguishing PD from MSA. •The radiomics-based nomogram was developed to differentiate between PD and MSA. •Combining PET/MRI radiomics-clinical model achieved promising performance to identify PD and MSA.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radiômica , Tomografia por Emissão de Pósitrons , Imageamento por Ressonância Magnética , Estudos Retrospectivos
2.
J Nanobiotechnology ; 22(1): 477, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39135044

RESUMO

The secondary injury is more serious after traumatic brain injury (TBI) compared with primary injury. Release of excessive reactive oxygen species (ROS) and Ca2+ influx at the damaged site trigger the secondary injury. Herein, a neutrophil-like cell membrane-functionalized nanoparticle was developed to prevent ROS-associated secondary injury. NCM@MP was composed of three parts: (1) Differentiated neutrophil-like cell membrane (NCM) was synthesized, with inflammation-responsive ability to achieve effective targeting and to increase the retention time of Mn3O4 and nimodipine (MP) in deep injury brain tissue via C-X-C chemokine receptor type 4, integrin beta 1 and macrophage antigen-1. (2) Nimodipine was used to inhibit Ca2+ influx, eliminating the ROS at source. (3) Mn3O4 further eradicated the existing ROS. In addition, NCM@MP also exhibited desirable properties for T1 enhanced imaging and low toxicity which may serve as promising multifunctional nanoplatforms for precise therapies. In our study, NCM@MP obviously alleviated oxidative stress response, reduced neuroinflammation, protected blood-brain barrier integrity, relieved brain edema, promoted the regeneration of neurons, and improved the cognition of TBI mice. This study provides a promising TBI management to relieve the secondary spread of damage.


Assuntos
Lesões Encefálicas Traumáticas , Cálcio , Nanopartículas , Neutrófilos , Espécies Reativas de Oxigênio , Animais , Espécies Reativas de Oxigênio/metabolismo , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Camundongos , Nanopartículas/química , Cálcio/metabolismo , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Masculino , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Camundongos Endogâmicos C57BL
3.
Appl Environ Microbiol ; 89(3): e0211222, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36880773

RESUMO

Cladophora represents a microscopic forest that provides many ecological niches and fosters a diverse microbiota. However, the microbial community on Cladophora in brackish lakes is still poorly understood. In this study, the epiphytic bacterial communities of Cladophora in Qinghai Lake were investigated at three life stages (attached, floating, and decomposing). We found that in the attached stage, Cladophora was enriched with chemoheterotrophic and aerobic microorganisms, including Yoonia-Loktanella and Granulosicoccus. The proportion of phototrophic bacteria was higher in the floating stage, especially Cyanobacteria. The decomposing stage fostered an abundance of bacteria that showed vertical heterogeneity from the surface to the bottom. The surface layer of Cladophora contained mainly stress-tolerant chemoheterotrophic and photoheterotrophic bacteria, including Porphyrobacter and Nonlabens. The microbial community in the middle layer was similar to that of floating-stage Cladophora. Purple oxidizing bacteria were enriched in the bottom layer, with Candidatus Chloroploca, Allochromatium, and Thiocapsa as the dominant genera. The Shannon and Chao1 indices of epibiotic bacterial communities increased monotonically from the attached stage to the decomposing stage. Microbial community composition and functional predictions indicate that a large number of sulfur cycle-associated bacteria play an important role in the development of Cladophora. These results suggest that the microbial assemblage on Cladophora in a brackish lake is complex and contributes to the cycling of materials. IMPORTANCE Cladophora represents a microscopic forest that provides many ecological niches fostering a diverse microbiota, with a complex and intimate relationship between Cladophora and bacteria. Many studies have focused on the microbiology of freshwater Cladophora, but the composition and succession of microorganisms in different life stages of Cladophora, especially in brackish water, have not been explored. In this study, we investigated the microbial assemblages in the life stages of Cladophora in the brackish Qinghai Lake. We show that heterotrophic and photosynthetic autotrophic bacteria are enriched in attached and floating Cladophora, respectively, whereas the epiphytic bacterial community shows vertical heterogeneity in decomposing mats.


Assuntos
Clorófitas , Cianobactérias , Microbiota , Rhodobacteraceae , Lagos/microbiologia , Proteobactérias , Clorófitas/microbiologia
4.
Int J Syst Evol Microbiol ; 72(11)2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36748686

RESUMO

A novel, Gram-stain-negative, rod-shaped, strictly anaerobic bacterium of genus Proteiniphilum of the phylum Bacteroidota, named strain JNU-WLY501T, was isolated from pit clay used to produce strong aroma-type liquor in PR China. The genomic DNA G+C content and genome size of JNU-WLY501T were 41.4 % and 3.9 Mbp, respectively. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that JNU-WLY501T was closely related to Proteiniphilum acetatigenes DSM 18083T (95.7 %) and Proteiniphilum saccharofermentans M3/6T (94.9 %). The pairwise average nucleotide identity based on blast and average amino acid identity values of JNU-WLY501T compared with Proteiniphilum saccharofermentans M3/6T were 73.6 and 77.3 %, respectively, which both were lower than the threshold values for bacterial species delineation. The strain grew at 20-40 °C, with optimum growth at 37 °C. The pH range for growth was 5.4-9.1, with optimum growth at pH 7.5. The sodium chloride range for growth was 0.0-4.0 %, with optimum growth at 0 %. The strain did not use glucose, maltose, fructose or starch. Yeast extract, tryptone and peptone supported the growth of JNU-WLY501T, and the main fermentation products were acetate and propionate. The predominant cellular fatty acids (>5 %) of JNU-WLY501T were anteiso-C15 : 0 (30.6 %), anteiso-C17 : 0 (26.1 %), C16 : 0 (7.7 %), iso-C16 : 0 (5.0 %) and iso-C17 : 0 (5.0 %). The respiratory quinone of JNU-WLY501T was MK-5. On the basis of the morphological, physiological, biochemical, chemotaxonomic, genotypic and phylogenetic results, JNU-WLY501T represents a novel species of the genus Proteiniphilum, for which the name Proteiniphilum propionicum sp. nov. is proposed. The type strain is JNU-WLY501T (=GDMCC 1.2686T=JCM 34753T).


Assuntos
Bebidas Alcoólicas , Bacteroidetes , Argila , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Argila/microbiologia , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação
5.
J Environ Manage ; 313: 114977, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35367675

RESUMO

The process of ecological restoration in eutrophic lakes, often results in the blooming of the filamentous green algae Cladophora. This consequently affects the growth of submerged plants and the restoration of vegetation. However, the blooming process of Cladophora and the environmental factors affecting their growth are poorly understood. This has become a difficult problem in the management of lakes. The study therefore focused on succession process of Cladophora blooms and their driving factors through mesocosm experiments in Caohai Lake. The results of our experiment indicated that Cladophora growth was mainly affected by water temperature, turbidity and soluble reactive phosphorus concentration of the habitat where Elodea nuttallii and Cladophora coexist. Nuisance Cladophora was mainly affected by turbidity (>19.24 NTU) when the water temperature was above 15.7 °C. With increasing Cladophora biomass and decreasing turbidity (<4.88 NTU), Cladophora biomass accumulation was mainly limited by the soluble reactive phosphorus concentration (<3.2 µg/L). Recorded turbidity range of 9.54-13.19 NTU was found to cause dramatic changes in the biomass of Cladophora. The results also showed that the outbreak of Cladophora blooms was mainly attributed to turbidity when the water temperature was appropriate in eutrophic lakes. These findings suggest that successful management efforts should strengthen the monitoring of transparency change in addition to controlling the phosphorus concentration to limit the Cladophora overgrowth on lake ecological restoration.


Assuntos
Clorófitas , Lagos , China , Eutrofização , Fósforo/análise , Água
6.
Appl Environ Microbiol ; 87(20): e0120321, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34378978

RESUMO

The transformation of diverse feedstocks into medium-chain fatty acids (MCFAs) by mixed cultures is a promising biorefinery route because of the high value of MCFAs. A particular concern is how to maintain the microbial consortia in mixed cultures to achieve stable MCFA production. The Chinese strong aroma-type liquor (Baijiu) fermentation system continually produces caproic acid for decades through a spontaneous inoculation of anaerobes from pit mud into fermented grains. Therefore, illuminating the dominant caproate-producing bacterium (CPB) in pit mud and how the CPB is sustained in the spontaneous fermentation system will help to reveal the microbiological mechanisms of stable caproate production. Here, we examined pit mud samples across four Chinese strong aroma-type Baijiu-producing areas and found that a caproate-producing Caproicibacterium sp. was widely distributed in these distilleries, with relative abundance ranging from 1.4 to 35.5% and an average abundance of 11.4%. Through controlling carbon source availability, we obtained different simplified caproate-producing consortia and found that the growth advantage of Caproicibacterium sp. was highly dependent on glucose. Then, two strains, named Caproicibacterium sp. strain LBM19010 and Caproicibacterium sp. strain JNU-WLY1368, were isolated from pit mud of two regions. The metabolic versatility of this species utilizing starch, maltose, glucose, and lactate reflected its adaptability to the fermentation environment where these carbon sources coexist. The simultaneous utilization of glucose and lactate contributed to the balance between cell growth and pH homeostasis. This study reveals that multiple adaptation strategies employed by the predominant CPB promotes its stability and dominance in a saccharide- and lactate-rich anaerobic habitat. IMPORTANCE The Chinese strong aroma-type liquor (Baijiu) fermentation environment is a typical medium-chain fatty acid-producing system with complex nutrients. Although several studies have revealed the correlation between microbial community composition and abiotic factors, the adaptation mechanisms of dominant species to abiotic environment are still unknown in this special anaerobic habitat. This study identified the predominant CPB in Chinese strong aroma-type Baijiu fermentation system. Metabolic versatility and flexibility of the dominant CPB with a small-size genome indicated that this bacterium can effectively exploit available carbon and nitrogen sources, which could be a key factor to promote its ecological success in a multispecies environment. The understanding of growth and metabolic features of the CPB responsible for its dominance in microbial community will not only contribute to the improvement of Chinese strong aroma-type Baijiu production but also expand its potential industrial applications in caproate production.


Assuntos
Bebidas Alcoólicas , Caproatos/metabolismo , Firmicutes/metabolismo , Adaptação Fisiológica , Anaerobiose , Fermentação , Glucose/metabolismo , Ácido Láctico/metabolismo , Microbiota/genética , RNA Ribossômico 16S/genética
7.
Chirality ; 33(12): 931-937, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34651347

RESUMO

An efficient preparation of (R)-2-(2,5-difluorophenyl)pyrrolidine ((R)-1) from the racemate based on a recycle process of resolution/racemization was described. In the process, the desired (R)-1 was obtained by resolution with D-malic acid in 95% EtOH. Meanwhile, the undesired (S)-1 could be racemized in the presence of potassium hydroxide in DMSO. After three times of recycle process, the desired freebase (R)-1 was obtained in a yield of 61.7% with excellent ee (98.4%).

8.
Bioorg Med Chem Lett ; 29(2): 225-229, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30522954

RESUMO

A new series of 1-substituted pyrazolopyrimidine derivatives were synthesized as potent BTK inhibitors and they were evaluated by enzyme-based assay and anti-proliferation against multiple B-cell lymphoma cell lines in vitro. Among these compounds, 9h exhibited the highest potency against BTK enzyme, with IC50 value of 4.2 nM. In particular, 8 and 9f performed better inhibition against the proliferation of B lymphoma cell lines DOHH2 and WSU-DLCL2 than the clinical drug ibrutinb. In addition, the test toward the normal PBMC cells showed that 8 possessed low cell cytotoxicity. All these explorations indicated that 8 could serve as a valuable anti-tumor agent for B-cell lymphoblastic leukemia treatment.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Antineoplásicos/farmacologia , Leucemia de Células B/tratamento farmacológico , Pirimidinas/farmacologia , Tirosina Quinase da Agamaglobulinemia/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Leucemia de Células B/metabolismo , Leucemia de Células B/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade
9.
Bioorg Med Chem ; 26(8): 2165-2172, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29567295

RESUMO

A series of 3-substituted pyrazolopyrimidine derivatives as BTK inhibitors were designed by structure-based drug design and they were synthesized, evaluated by enzyme-based assay and anti-proliferation against Ramos and Raji cells. Most of them displayed good inhibitory activities against both BTK and B-cell lymphoblastic leukemia lines in vitro. Among them, compound 8a exhibited excellent potency (IC50 = 7.95 nM against BTK enzyme, 8.91 µM against Ramos cells and 1.80 µM against Raji cells), with a better hydrophilicity (ClogP = 3.33). These explorations provided new clues to discover 3-substituted pyrazolopyrimidine derivatives as novel anti-tumor agents.


Assuntos
Desenho de Fármacos , Inibidores de Proteínas Quinases/síntese química , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/química , Pirimidinas/química , Tirosina Quinase da Agamaglobulinemia , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/metabolismo , Pirazóis/metabolismo , Pirazóis/farmacologia , Pirimidinas/metabolismo , Pirimidinas/farmacologia , Relação Estrutura-Atividade
10.
Beilstein J Org Chem ; 14: 1421-1427, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977405

RESUMO

In order to prepare asymmetrically (R)-(+)-1-(5-bromopentyl)-1-methyl-7-methoxy-2-tetralone (3a), a key intermediate of dezocine, 17 cinchona alkaloid-derived catalysts were prepared and screened for the enantioselective alkylation of 1-methyl-7-methoxy-2-tetralone with 1,5-dibromopentane, and the best catalyst (C7) was identified. In addition, optimizations of the alkylation were carried out so that the process became practical and effective.

11.
Beilstein J Org Chem ; 14: 2340-2347, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30254698

RESUMO

In order to prepare eptazocine hydrobromide effectively, a novel, mild and practical asymmetric process was developed starting from 1-methyl-7-methoxy-2-tetralone under the catalysis of N-(p-trifluoromethylbenzyl)cinchonidinium bromide. The reaction conditions were optimized to obtain the product in excellent overall yield and purity.

12.
Bioorg Med Chem Lett ; 27(8): 1854-1858, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28285910

RESUMO

The emergence and spread of multidrug-resistant strains of the human pathological bacteria are generating a threat to public health worldwide. In the current study, a series of PC190723 derivatives was synthesized and investigated for their antimicrobial activity. The compounds exhibited good activity against several Gram-positive bacteria as determined by comparison of diameters of the zone of inhibition of test compounds and standard antibiotics. Compound 9 with a fluorine substitution on the phenyl ring showed the best antibacterial activity in the series against M. smegmatis with the zone ratio of 0.62, and against S. aureus with the zone ratio of 0.44. The results from this study indicate that based on the unique 3-methoxybenzamide pharmacophore, compound 9 may represent a promising lead candidate against Gram-positive bacteria that are worthy of further investigation.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Benzamidas/química , Benzamidas/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Piridinas/química , Piridinas/farmacologia , Tiazóis/química , Tiazóis/farmacologia , Bacillus subtilis/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Mycobacterium smegmatis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
13.
Beilstein J Org Chem ; 13: 1064-1070, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28684985

RESUMO

A concise and practical stereoselective synthesis of ipragliflozin L-proline was presented starting from 2-[(5-iodo-2-fluorophenyl)methyl]-1-benzothiophene and 2,3,4,6-tetra-O-pivaloyl-α-D-glucopyranosyl bromide without catalyst via iodine-lithium-zinc exchange. The overall yield was 52% in three steps and the product purity was excellent. Two key diastereomers were prepared with efficient and direct access to the α-C-arylglucoside.

14.
Beilstein J Org Chem ; 11: 2641-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26734109

RESUMO

A novel and practical asymmetric synthesis of dapoxetine hydrochloride by using the chiral auxiliary (S)-tert-butanesulfinamide was explored. The synthesis was concise, mild, and easy to perform. The overall yield and stereoselectivity were excellent.

15.
Insights Imaging ; 15(1): 5, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185779

RESUMO

OBJECTIVES: To develop and validate a machine learning model using 18F-FDG PET/CT radiomics signature and clinical features to predict the presence of micropapillary and solid (MP/S) components in lung adenocarcinoma. METHODS: Eight hundred and forty-six patients who underwent preoperative PET/CT with pathologically confirmed adenocarcinoma were enrolled. After segmentation, 1688 radiomics features were extracted from PET/CT and selected to construct predictive models. Then, we developed a nomogram based on PET/CT radiomics integrated with clinical features. Receiver operating curves, calibration curves, and decision curve analysis (DCA) were performed for diagnostics assessment and test of the developed models for distinguishing patients with MP/S components from the patients without. RESULTS: PET/CT radiomics-clinical combined model could well distinguish patients with MP/S components from those without MP/S components (AUC = 0.87), which performed better than PET (AUC = 0.829, p < 0.05) or CT (AUC = 0.827, p < 0.05) radiomics models in the training cohort. In test cohorts, radiomics-clinical combined model outperformed the PET radiomics model in test cohort 1 (AUC = 0.859 vs 0.799, p < 0.05) and the CT radiomics model in test cohort 2 (AUC = 0.880 vs 0.829, p < 0.05). Calibration curve indicated good coherence between all model prediction and the actual observation in training and test cohorts. DCA revealed PET/CT radiomics-clinical model exerted the highest clinical benefit. CONCLUSION: 18F-FDG PET/CT radiomics signatures could achieve promising prediction efficiency to identify the presence of MP/S components in adenocarcinoma patients to help the clinician decide on personalized treatment and surveillance strategies. The PET/CT radiomics-clinical combined model performed best. CRITICAL RELEVANCE STATEMENT: 18F-FDG PET/CT radiomics signatures could achieve promising prediction efficiency to identify the presence of micropapillary and solid components in adenocarcinoma patients to help the clinician decide on personalized treatment and surveillance strategies.

16.
Chem Pharm Bull (Tokyo) ; 61(4): 477-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23358258

RESUMO

A series of xanthine derivatives in which a methylene was inserted at position 8 of xanthine scaffold was synthesized and evaluated as inhibitors of dipeptidyl peptidase 4 (DPP-4) for the treatment of type 2 diabetes. As the results of structure-activity relationship (SAR) study of the series, the compounds with 4-methyl-quinazoline-2-yl-methyl group at N-1 position and 2-aminoethylaminomethyl group gave better activities. Compounds H4 and H9 showed good DPP-4 inhibition and more than 100-fold selectivity over DPP-7 and DPP-8.


Assuntos
Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/síntese química , Xantina/química , Sítios de Ligação , Domínio Catalítico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/química , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Dipeptidil Peptidases e Tripeptidil Peptidases/antagonistas & inibidores , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Xantina/síntese química , Xantina/uso terapêutico
17.
Sci Total Environ ; 901: 165937, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37532035

RESUMO

Biological soil crusts (BSCs) are an important biological component of the soil surface, covering approximately 12 % of the Earth's land surface. Although BSCs are closely related to habitats, the microbial diversity and spatial variability of BSCs in different ecosystems are still unclear, especially on the Qinghai-Tibet Plateau (QTP), where climate is changeable and habitats are complex. Here, we investigated the diversity, assembly processes, spatial distribution pattern and driving factors of prokaryotic and eukaryotic microbial communities in BSCs in four habitats on the QTP. It was found that habitat-specific environmental factors regulated the composition, diversity and spatial variability of BSC microbial communities. Soil organic carbon and soil water content were the most important factors (R2 = 0.9024, P = 0.001; R2 = 0.8004, P = 0.001) affecting the spatial differences in prokaryotes and eukaryotes, respectively. Under the specific climate of the QTP, the spatial pattern of microbial communities in BSCs was controlled by precipitation rather than temperature. In addition, ecological processes further explained the effects of habitat specificity, and environmental filtering explained microbial community differences better than dispersal limitation. The results of the neutral community model and the normalized stochastic ratio index revealed that the assembly of prokaryotic communities was determined by deterministic processes at the regional scale, and at the local scale, the assembly process was mainly determined by habitat type, while the assembly of eukaryotic communities was determined by stochastic processes at both the regional and local scales. This study provided a scientific reference for the prediction of BSC distribution and resource conservation under future climate change scenarios.


Assuntos
Microbiota , Solo , Tibet , Carbono , Biota , Microbiologia do Solo
18.
Clin Nucl Med ; 48(9): 799-801, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37418283

RESUMO

ABSTRACT: We report cardiac 18 F-FAPI PET/CT findings in 3 cases with myocarditis of varying duration (7 hours, 1 week, and 1 month). Myocarditis with varying symptom durations showed different 18 F-FAPI uptake, suggesting that the 18 F-FAPI PET/CT may be helpful in evaluating the extent of fibrosis caused by myocarditis. This information may assist in treatment decision-making for patients with myocarditis.


Assuntos
Miocardite , Humanos , Miocardite/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Transporte Biológico , Radioisótopos de Gálio , Fluordesoxiglucose F18
19.
Water Res ; 244: 120430, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37678037

RESUMO

Anionic surfactants represented by linear alkylbenzene sulfonate (LAS) exhibit vertical heterogeneity of concentrations in aquatic environments owing to their amphiphilic structure. Field investigations showed that the concentration of anionic surfactants (mainly LAS) in the water surface microlayer (SML) of Lake Taihu reached 580 µg/L, higher than that in the lower layer. Floating Microcystis blooms overlap in space with the high concentration of anionic surfactants in SML. However, few studies have focused on the effects of anionic surfactants (e.g., LAS) on the interspecies competition between toxic and nontoxic Microcystis. In this study, coculture and monoculture experiments were conducted with both toxic and nontoxic Microcystis species to explore how the environmental concentration of LAS regulates the dominance of toxic Microcystis and toxicity from the perspective of photosynthesis, species dominance, and MC production. The results showed that LAS concentrations above 0.267 or 0.431 mg/L (depending on light conditions) selectively promoted the photosynthetic competitive advantage of toxic Microcystis, leading to its higher population proportion in the community. Additionally, LAS concentrations above 0.5 mg/L induced the synthesis and release of microcystins (MCs). The results of chlorophyll fluorescence analysis, electron microscopy and transcriptome sequencing suggested that compared with nontoxic Microcystis, toxic Microcystis can better resist LAS stress by dissipating excess light, maintaining an intact membrane structure and maintaining cellular homeostasis. Transcriptome sequencing revealed that the photosynthetic damage of nontoxic Microcystis might be attributed to the impacts of LAS on the absorption and assimilation of nitrogen, which finally resulted in the degradation of phycobilisomes. This study can provide novel insight for establishing standards and safety management of wastewater discharge.


Assuntos
Ácidos Alcanossulfônicos , Microcystis , Lagos , Fotossíntese
20.
Sci Total Environ ; 859(Pt 1): 160222, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36400299

RESUMO

Geosmin has been commonly detected both in various aquatic environments and biota, but its exact toxicological mechanisms to organisms need further experimentation. In the present study, zebrafish embryos were exposed to geosmin at nominal concentrations of 50, 500 and 5000 ng/L for 120 h post-fertilization (hpf), followed by locomotor activity and biochemical parameter examination, and multi-omics investigation of the transcriptome and metabolome. The results showed that geosmin exposure significantly reduced the mitochondrial electron transport chain (ETC) complexes I-V, ATP content and mitochondrial respiration and suppressed the locomotor behavior of zebrafish larvae. Transcriptomics analysis revealed that the transcripts of genes involved in oxidative phosphorylation, glycolysis, and lipid metabolism were significantly affected, indicating that geosmin disrupts energy metabolism. Furthermore, metabolomics results showed that 3 classes of lipids, namely glycerophospholipids (GPs), sphingolipids (SLs) and fatty acyls (FAs) were significantly decreased after geosmin exposure. This study provides novel insight into the underlying mechanisms of geosmin-induced energy metabolism and highlights the need for concern about geosmin exposure.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Estresse Oxidativo , Metabolismo Energético , Larva , Mitocôndrias/metabolismo , Embrião não Mamífero/metabolismo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
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