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1.
Small ; 20(4): e2305879, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37715100

RESUMO

Central metal exchange can innovatively open the cavity of metal-organic frameworks (MOFs) by alternating the framework topology. Here, the single-crystal-to-single-crystal (SC-SC) transformation is reported from a Co-based MOF {[Co1.25 (HL)0.5 (Pz-NH2 )0.25 (µ3 -O)0.25 (µ2 -OH)0.25 (H2 O)]·0.125 Co·0.125 L·10.25H2 O}n (Co-MOF, L = 5,5'-(1H-2,3,5-triazole-1,4-diyl)diisophthalic acid) into two novel MOF materials, {[Cu1.75 L0.75 (Pz-NH2 )0.125 (µ3 -O)0.125 (µ2 -OH)0.25 (H2 O)0.375 ]•3CH3 CN}n (Cu-MOF) and {[Zn1.75 L0.625 (Pz-NH2 )0.25 (µ3 -O)0.25 (µ2 -O)0.25 (H2 O)1.25 ]•4CH3 CN}n (Zn-MOF), through exchanging the Co2+ in the MOF into Cu2+ or Zn2+ , respectively. The free Co2+ and L4- in the Co-MOF channels fuse with the skeleton during the Co→Cu and Co→Zn exchange processes, leading to the expansion of the channel space and the transformation of the secondary building units (SBUs) to form an adjustable skeleton. The nonlinear optical response results show that the MOFs generated by the exchange of the central metal exhibit different saturable absorption and the self-focusing effect. In addition, loading polypyrrole (PPy) into the MOFs can not only improve the stability of the MOFs but also further optimize the nonlinear optical behavior. This work suggests that SC-SC central metal exchange and the introduction of polymer molecules can tune the nonlinear optical response, which provides a new perspective for the future study of nonlinear optical materials.

2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(1): 47-51, 2022 Jan 30.
Artigo em Zh | MEDLINE | ID: mdl-35150107

RESUMO

In order to effectively prevent the damage to the human body caused by abnormal oxygen concentration in the medical hyperbaric oxygen chamber, a ZigBee-based medical hyperbaric oxygen chamber oxygen concentration automatic control system is designed. The data acquisition module uses the microprocessor STM32F103C8T6 to receive the oxygen concentration data of each acquisition point, and the ZigBee of the data processing module transmits the processing results to the MSP430G2553 single-chip microcomputer at the receiving end of the slave. The MSP430G2553 single-chip microcomputer uses a self-organizing TS fuzzy neural network (SOTSFNN) and adds activation. The intensity concept realizes automatic control of the oxygen concentration in the hyperbaric oxygen chamber, and controls the buzzer to give an alarm when the oxygen concentration is lower than 19 mg/L and higher than 23 mg/L, and displays the current real-time oxygen concentration through LCD12864. The experimental results show that as the communication distance increases, the packet loss rate of the system is always lower than 5%, and the signal strength under the same communication distance is better; the system can effectively control the oxygen concentration value within the set range, and the oxygen concentration. The control accuracy is high and the stability is good.


Assuntos
Oxigenoterapia Hiperbárica , Humanos , Microcomputadores , Oxigênio
3.
Chemistry ; 27(15): 5011-5018, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33438786

RESUMO

A 3D Co-based metal-organic framework (Co-MOF) with two kinds of large pores filled by free Co2+ ions and ligands was synthesized and characterized. To expand the MOF structure and conductivity, the free Co2+ ions and ligands were exchanged by conductive ionic liquid EtpyBr and photosensitive AgNO3 through single crystal-to-single crystal transformation, which produced structure-changed 3D MOFs Co-MOF-Br and Co-Ag-MOF, which were characterized by single-crystal X-ray diffraction. Incorporating small quantities of doped polyaniline (PANI) with redox activity into the pores could further tune the stability and conductivity of the three MOFs. The PANI/MOFs all show outstanding electrical conductivity (≈10-2  S cm-1 ), and PANI/Co-MOF-Br has the largest p-type Seebeck coefficient of 66.6 µV K-1 . PANI/Co-MOF-Br and PANI/Co-Ag-MOF have 4 and 15 times higher photocurrent density compared with PANI/Co-MOF, respectively. This work sheds light on the design of advanced electrically conductive 3D MOFs.

4.
Inorg Chem ; 60(24): 18593-18597, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34822244

RESUMO

The relationship between the aggregation states of pyrene-based linkers and the photoluminescence/photoelectric performance was well studied by the formation of an anionic metal-organic framework, [BMI]2[Mg3(TBAPy)2(H2O)4]·2dioxane, which shows highly enhanced light-harvesting and photoelectric conversion efficiency by the encapsulation of D-π-A cation dyes.

5.
Chemistry ; 22(18): 6389-96, 2016 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-26997347

RESUMO

Different morphologies and particle sizes of two crystalline zinc-based coordination polymers (CPs), [Zn(pytz)H2 O]n (1; H2 pytz=2,6-bis(tetrazole)pyridine) and [Zn2 (pytz)2 4 H2 O] (2), from the bulk scale to the nanoscale, could be obtained under solvothermal conditions with different surfactants (polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG) 2000) as templates. PVP and PEG 2000 could act as capping and structure-directing agents, respectively, to influence the growth of crystalline particles and control their sizes. CP 1 exhibits a two-dimensional framework with window-like units and 2 shows a bimetallic structure. Nanocrystalline 1 and 2 were used as heterogeneous catalysts to study how adjacent catalytic active sites synergistically effected their catalytic reactivities in the direct catalytic conversion of aromatic dinitriles into oxazolines. The results showed that 1 produced bis-oxazolines as the sole products, whereas 2 gave the mono-oxazolines as the major products under the same reaction conditions.

6.
Sci Adv ; 10(33): eadn3316, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39141729

RESUMO

Genetic variations are instrumental for unraveling phage evolution and deciphering their functional implications. Here, we explore the underlying fine-scale genetic variations in the gut phageome, especially structural variations (SVs). By using virome-enriched long-read metagenomic sequencing across 91 individuals, we identified a total of 14,438 nonredundant phage SVs and revealed their prevalence within the human gut phageome. These SVs are mainly enriched in genes involved in recombination, DNA methylation, and antibiotic resistance. Notably, a substantial fraction of phage SV sequences share close homology with bacterial fragments, with most SVs enriched for horizontal gene transfer (HGT) mechanism. Further investigations showed that these SV sequences were genetic exchanged between specific phage-bacteria pairs, particularly between phages and their respective bacterial hosts. Temperate phages exhibit a higher frequency of genetic exchange with bacterial chromosomes and then virulent phages. Collectively, our findings provide insights into the genetic landscape of the human gut phageome.


Assuntos
Bactérias , Bacteriófagos , Microbioma Gastrointestinal , Transferência Genética Horizontal , Bacteriófagos/genética , Humanos , Microbioma Gastrointestinal/genética , Bactérias/virologia , Bactérias/genética , Metagenômica/métodos , Variação Genética , Viroma/genética , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala
7.
Adv Sci (Weinh) ; 11(13): e2305818, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38240578

RESUMO

Current metagenome assembled human gut phage catalogs contained mostly fragmented genomes. Here, comprehensive gut virome detection procedure is developed involving virus-like particle (VLP) enrichment from ≈500 g feces and combined sequencing of short- and long-read. Applied to 135 samples, a Chinese Gut Virome Catalog (CHGV) is assembled consisting of 21,499 non-redundant viral operational taxonomic units (vOTUs) that are significantly longer than those obtained by short-read sequencing and contained ≈35% (7675) complete genomes, which is ≈nine times more than those in the Gut Virome Database (GVD, ≈4%, 1,443). Interestingly, the majority (≈60%, 13,356) of the CHGV vOTUs are obtained by either long-read or hybrid assemblies, with little overlap with those assembled from only the short-read data. With this dataset, vast diversity of the gut virome is elucidated, including the identification of 32% (6,962) novel vOTUs compare to public gut virome databases, dozens of phages that are more prevalent than the crAssphages and/or Gubaphages, and several viral clades that are more diverse than the two. Finally, the functional capacities are also characterized of the CHGV encoded proteins and constructed a viral-host interaction network to facilitate future research and applications.


Assuntos
Bacteriófagos , Humanos , Bacteriófagos/genética , Análise de Sequência , Genoma Viral/genética , Metagenoma/genética , Fezes
8.
Gut Microbes ; 15(1): 2205386, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37140125

RESUMO

Cross-cohort validation is essential for gut-microbiome-based disease stratification but was only performed for limited diseases. Here, we systematically evaluated the cross-cohort performance of gut microbiome-based machine-learning classifiers for 20 diseases. Using single-cohort classifiers, we obtained high predictive accuracies in intra-cohort validation (~0.77 AUC), but low accuracies in cross-cohort validation, except the intestinal diseases (~0.73 AUC). We then built combined-cohort classifiers trained on samples combined from multiple cohorts to improve the validation of non-intestinal diseases, and estimated the required sample size to achieve validation accuracies of >0.7. In addition, we observed higher validation performance for classifiers using metagenomic data than 16S amplicon data in intestinal diseases. We further quantified the cross-cohort marker consistency using a Marker Similarity Index and observed similar trends. Together, our results supported the gut microbiome as an independent diagnostic tool for intestinal diseases and revealed strategies to improve cross-cohort performance based on identified determinants of consistent cross-cohort gut microbiome alterations.


Assuntos
Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Aprendizado de Máquina , Projetos de Pesquisa , Metagenoma , Metagenômica/métodos
9.
Cell Cycle ; 22(21-22): 2467-2484, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38179789

RESUMO

Pathological cardiac hypertrophy (referred to as cardiac hypertrophy) is a maladaptive response of the heart to a variety of pathological stimuli, and cardiac hypertrophy is an independent risk factor for heart failure and sudden death. Currently, the treatments for cardiac hypertrophy are limited to improving symptoms and have little effect. Elucidation of the developmental process of cardiac hypertrophy at the molecular level and the identification of new targets for the treatment of cardiac hypertrophy are crucial. In this review, we summarize the research on multiple active substances related to the pathogenesis of cardiac hypertrophy and the signaling pathways involved and focus on the role of transforming growth factor-ß (TGF-ß) and bone morphogenetic protein (BMP) signaling in the development of cardiac hypertrophy and the identification of potential targets for molecular intervention. We aim to identify important signaling molecules with clinical value and hope to help promote the precise treatment of cardiac hypertrophy and thus improve patient outcomes.


Assuntos
Transdução de Sinais , Fator de Crescimento Transformador beta , Humanos , Fator de Crescimento Transformador beta/metabolismo , Cardiomegalia , Proteínas Morfogenéticas Ósseas/metabolismo , Fatores de Crescimento Transformadores , Proteína Morfogenética Óssea 2
10.
Front Cardiovasc Med ; 9: 1066065, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36440039

RESUMO

A young man repeatedly found a right atrial mass with severe wheezing and extreme dyspnea. His condition was critical and complicated. The process of correct diagnosis was full of twists and turns. Finally, he got better and was discharged from the hospital after anticoagulation therapy, which suggested that correct clinical thinking and decision are particularly important in the process of diagnosis and treatment.

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