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Iron-chalcogenide superconductors FeSe1-xSx possess unique electronic properties such as nonmagnetic nematic order and its quantum critical point. The nature of superconductivity with such nematicity is important for understanding the mechanism of unconventional superconductivity. A recent theory suggested the possible emergence of a fundamentally new class of superconductivity with the so-called Bogoliubov Fermi surfaces (BFSs) in this system. However, such an ultranodal pair state requires broken time-reversal symmetry (TRS) in the superconducting state, which has not been observed experimentally. Here, we report muon spin relaxation (µSR) measurements in FeSe1-xSx superconductors for 0 ≤ x ≤ 0.22 covering both orthorhombic (nematic) and tetragonal phases. We find that the zero-field muon relaxation rate is enhanced below the superconducting transition temperature Tc for all compositions, indicating that the superconducting state breaks TRS both in the nematic and tetragonal phases. Moreover, the transverse-field µSR measurements reveal that the superfluid density shows an unexpected and substantial reduction in the tetragonal phase (x > 0.17). This implies that a significant fraction of electrons remain unpaired in the zero-temperature limit, which cannot be explained by the known unconventional superconducting states with point or line nodes. The TRS breaking and the suppressed superfluid density in the tetragonal phase, together with the reported enhanced zero-energy excitations, are consistent with the ultranodal pair state with BFSs. The present results reveal two different superconducting states with broken TRS separated by the nematic critical point in FeSe1-xSx, which calls for the theory of microscopic origins that account for the relation between nematicity and superconductivity.
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Single-cell transcriptome has enabled the transcriptional profiling of thousands of immune cells in complex tissues and cancers. However, subtle transcriptomic differences in immune cell subpopulations and the high dimensionality of transcriptomic data make the clustering and annotation of immune cells challenging. Herein, we introduce ImmCluster (http://bio-bigdata.hrbmu.edu.cn/ImmCluster) for immunology cell type clustering and annotation. We manually curated 346 well-known marker genes from 1163 studies. ImmCluster integrates over 420 000 immune cells from nine healthy tissues and over 648 000 cells from different tumour samples of 17 cancer types to generate stable marker-gene sets and develop context-specific immunology references. In addition, ImmCluster provides cell clustering using seven reference-based and four marker gene-based computational methods, and the ensemble method was developed to provide consistent cell clustering than individual methods. Five major analytic modules were provided for interactively exploring the annotations of immune cells, including clustering and annotating immune cell clusters, gene expression of markers, functional assignment in cancer hallmarks, cell states and immune pathways, cell-cell communications and the corresponding ligand-receptor interactions, as well as online tools. ImmCluster generates diverse plots and tables, enabling users to identify significant associations in immune cell clusters simultaneously. ImmCluster is a valuable resource for analysing cellular heterogeneity in cancer microenvironments.
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Perfilação da Expressão Gênica , Sistema Imunitário , Humanos , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Neoplasias/genética , Neoplasias/imunologia , Transcriptoma , Microambiente Tumoral/genética , Sistema Imunitário/citologia , Comunicação Celular , Marcadores GenéticosRESUMO
With its estrogenic activity, (S)-equol plays an important role in maintaining host health and preventing estrogen-related diseases. Exclusive production occurs through the transformation of soy isoflavones by intestinal bacteria, but the reasons for variations in (S)-equol production among different individuals and species remain unclear. Here, fecal samples from humans, pigs, chickens, mice, and rats were used as research objects. The concentrations of (S)-equol, along with the genetic homology and evolutionary relationships of (S)-equol production-related genes [daidzein reductase (DZNR), daidzein racemase (DDRC), dihydrodaidzein reductase (DHDR), tetrahydrodaidzein reductase (THDR)], were analyzed. Additionally, in vitro functional verification of the newly identified DDRC gene was conducted. It was found that approximately 40% of human samples contained (S)-equol, whereas 100% of samples from other species contained (S)-equol. However, there were significant variations in (S)-equol content among the different species: rats > pigs > chickens > mice > humans. The distributions of the four genes displayed species-specific patterns. High detection rates across various species were exhibited by DHDR, THDR, and DDRC. In contrast, substantial variations in detection rates among different species and individuals were observed with respect to DZNR. It appears that various types of DZNR may be associated with different concentrations of (S)-equol, which potentially correspond to the regulatory role during (S)-equol synthesis. This enhances our understanding of individual variations in (S)-equol production and their connection with functional genes in vitro. Moreover, the newly identified DDRC exhibits higher potential for (S)-equol synthesis compared to the known DDRC, providing valuable resources for advancing in vitro (S)-equol production. IMPORTANCE: (S)-equol ((S)-EQ) plays a crucial role in maintaining human health, along with its known capacity to prevent and treat various diseases, including cardiovascular diseases, metabolic syndromes, osteoporosis, diabetes, brain-related diseases, high blood pressure, hyperlipidemia, obesity, and inflammation. However, factors affecting individual variations in (S)-EQ production and the underlying regulatory mechanisms remain elusive. This study examines the association between functional genes and (S)-EQ production, highlighting a potential correlation between the DZNR gene and (S)-EQ content. Various types of DZNR may be linked to the regulation of (S)-EQ synthesis. Furthermore, the identification of a new DDRC gene offers promising prospects for enhancing in vitro (S)-EQ production.
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Equol , Isoflavonas , Animais , Humanos , Camundongos , Ratos , Suínos , Equol/genética , Equol/metabolismo , Racemases e Epimerases , Galinhas/metabolismo , Isoflavonas/metabolismo , Oxirredutases/metabolismoRESUMO
Medicago sativa polysaccharides (MSPs) are beneficial compounds extracted from Medicago sativa L. that exhibit multiple medicinal activities. However, little is known about their hypoglycemic effects. In this study, MSP-II-a, a neutral polysaccharide with an Mw of 4.3 × 104 Da, was isolated and purified from M. sativa L. Monosaccharide composition analysis determined that MSP-II-a was composed of arabinose, glucose, galactose, mannose, rhamnose, and xylose in a molar ratio of 2.1:4.0:1.1:0.4:1.4:1.1. Structural characterization of MSP-II was performed using a combination of methylation analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results showed that MSP-II-a was mainly comprised of 1,4-p-Glc, 1,3,4-Rha, and 1,3-p-Gal glycosidic linkages, revealing a mesh-like texture with irregular blade shapes. In vitro assays demonstrated that MSP-II-a, at concentrations of 200 and 400 µg/mL, promoted glucose uptake in insulin-resistant 3T3-L1 adipocytes. In vivo studies have shown that MSP-II-a significantly alleviates insulin resistance by reducing fasting blood glucose levels and increasing hepatic glycogen synthesis in HFD/STZ-induced diabetic mice. These findings revealed that MSP-II-a is a promising source of bioactive polysaccharides with potential hypoglycemic activity.
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A new compound xylarkarynone A (1), a first reported natural product compound xylarkarynone B (2) and eight known compounds (3-10) were isolated from Xylaria sp. HHY-2. Their structures were elucidated by spectroscopic methods, DP4+ probability analyses and electronic circular dichroism (ECD) calculations. The bioactivities of isolated compounds were assayed. Compound 1 exhibited obvious activity against A549 cells with an IC50 value of 6.12±0.28â µM. Additionally, compound 1 showed moderate antifungal activities against Plectosphaerella cucumerina and Aspergillus niger with minimum inhibitory concentrations (MICs) of both 16â µg/mL, which was at the same grade with positive control nystatin. Most compounds exhibited varying degrees of inhibitory activity against P. cucumerina, indicating that Xylaria sp. has potential as inhibitors against P. cucumerina.
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Antifúngicos , Aspergillus niger , Testes de Sensibilidade Microbiana , Sesquiterpenos , Xylariales , Humanos , Xylariales/química , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Aspergillus niger/efeitos dos fármacos , Células A549 , Ensaios de Seleção de Medicamentos Antitumorais , Ascomicetos/química , Estrutura Molecular , Conformação Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a DrogaRESUMO
Hepatocellular carcinoma (HCC), one of the most prevalent types of cancer worldwide, has an exceedingly poor prognosis. Tandem C2 domain nuclear protein (TC2N) has been implicated in tumorigenesis and serves as an oncogene or tumor suppressor in different types of cancer. Here, we explore the possible regulatory activities and molecular mechanisms of TC2N in HCC progression. However, TC2N expression was significantly upregulated in HCC tissues and hepatoma cell lines, and this upregulation was positively correlated with tumor progression in HCC patients. The ectopic overexpression of TC2N accelerated the proliferation, migration, and invasion of HCC cells, whereas its knockdown showed the opposite effects. Bioinformatics analysis showed that TC2N participates in the regulation of the Wnt/ß-catenin signaling pathway. Mechanistically, TC2N activated the Wnt/ß-catenin signaling pathway by regulating the expression levels of ß-catenin and its downstream targets CyclinD1, MMP7, c-Myc, c-Jun, AXIN2, and glutamine synthase. Furthermore, the deletion of ß-catenin effectively neutralized the regulation of TC2N in HCC proliferation and metastasis. Overall, this study showed that TC2N promotes HCC proliferation and metastasis by activating the Wnt/ß-catenin signaling pathway, indicating that TC2N might be a potential molecular target for the treatment of HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , beta Catenina/metabolismo , Via de Sinalização Wnt/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão GênicaRESUMO
Vibrio mimicus is a zoonotic pathogen that is widely distributed in aquatic habitats/environments (marine coastal water, estuaries, etc). The development of biocontrol agents for V. mimicus is imperative for the prevention and control of aquatic animal diseases and human food-borne infections. In this study, a broad-spectrum bacteriophage Vmp-1 was isolated from dealt aquatic product in a local market by double-layer agar plate method using V. mimicus CICC21613 as the host bacteria. Results indicated that Vmp-1, which belongs to the family Podoviridae, showed good pH tolerance (pH 3.0-12.0) and thermal stability (30-50 °C). The optimal multiplicity of infection (MOI) of Vmp-1 was 0.001 for a 20-min incubation and 100-min lysis period. Vmp-1 effectively controlled V. mimicus CICC21613 in LBS model (MOI = 0.0001, 0.001, 0.01, 0.1, 1) within 8 h. The full length of the Vmp-1 genome was 43,312 bp, with average GC content of 49.5%, and a total of 44 protein-coding regions. This study provides a novel phage strain that has the highest homology with vB_VpP_HA5 (GenBank: OK585159.1, 95.96%) for the development of biocontrol agents for V. mimicus.
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Bacteriófagos , Vibrio mimicus , Vibrio , Animais , Humanos , Bacteriófagos/genética , Genômica , Vibrio/genética , Vibrio mimicus/genética , Proteínas de Membrana/metabolismoRESUMO
BACKGROUND: Insertion and deletion (InDel) polymorphisms have considerable potential in the field of forensic genetics because of their low mutation rate and small amplicons. At present, InDel polymorphisms detection based on the technique of capillary electrophoresis is the main technique used in forensic DNA laboratory. However, this method is complicated and time-consuming, and is not suitable for rapid on-site paternity and personal identification. Next-generation sequencing analysis of InDels polymorphisms requires expensive instruments, large upfront reagent and supply costs, computational requirements and complex bioinformatics, increased the time to obtain results. Thus, there is an urgent need to establish a method to provide reliable, rapid, sensitive and economical genotyping for InDels. METHOD: A rapid InDels (32 InDels) panel was established using fluorogenic probes-based multiplex real-time PCR with microfluidic test cartridge and portable real-time PCR instrument. Then, we performed several validation studies including concordance, accuracy, sensitivity, stability, species specificity. RESULTS: It showed that the complete genotypes could be obtained from ≥100 pg of input DNA and from a series of challenging samples with high accuracy and specificity within 90 min. CONCLUSION: This method provides a rapid and cost-effective solution for InDels genotyping and personal identification in portable format.
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Antropologia Forense , Polimorfismo Genético , Humanos , Genótipo , Reação em Cadeia da Polimerase em Tempo Real , DNA/análiseRESUMO
BACKGROUND: Multidrug-resistant (MDR) bacteria-induced VAP often has high lethality. We present this systematic review and meta-analysis to assess the risk factors for MDR bacterial infection in patients with VAP. METHODS: PubMed, EMBASE, Web of Science, and Cochrane Library were searched for studies regarding MDR bacterial infection in VAP patients, from Jan 1996 to Aug 2022. Study selection, data extraction, and quality assessment of included studies were conducted by two reviewers independently, and potential risk factors for MDR bacterial infection were identified. RESULTS: Meta-analysis showed that the score of the Acute Physiology and Chronic Health Evaluation II (APACHE-II) [OR = 1.009, 95% (CI 0.732, 1.287)], Simplified Acute Physiology Score II (SAPS-II) [OR = 2.805, 95%CI (0.854, 4.755)], length of hospital-stay before VAP onset (days) [OR = 2.639, 95%CI (0.387, 4.892)], in-ICU duration [OR = 3.958, 95%CI (0.894, 7.021)], Charlson index [OR = 1.000, 95%CI (0.889, 1.111)], overall hospital-stay [OR = 20.742, 95%CI (18.894, 22.591)], Medication of Quinolones [OR = 2.017, 95%CI (1.339, 3.038)], medication of carbapenems [OR = 3.527, 95%CI (2.476, 5.024)], combination of more than 2 prior antibiotics [OR = 3.181, 95%CI (2.102, 4.812)], and prior use of antibiotics [OR 2.971, 95%CI (2.001, 4.412)] were independent risk factors of MDR bacterial infection in VAP patients. Diabetes and mechanical ventilation duration before VAP onset showed no association with risk for MDR bacterial infection. CONCLUSIONS: This study has identified 10 risk factors associated with MDR bacterial infection in VAP patients. Identification of these factors would be able to facilitate the treatment and prevention of MDR bacterial infection in clinical practice.
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Infecções Bacterianas , Pneumonia Associada à Ventilação Mecânica , Humanos , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Respiração Artificial/efeitos adversos , Antibacterianos/uso terapêutico , Fatores de Risco , Unidades de Terapia Intensiva , Bactérias , Infecções Bacterianas/tratamento farmacológicoRESUMO
The regulation of protein kinase B (AKT) phosphorylation by Tripartite motif-containing protein 31 (TRIM31) is implicated as an essential mechanism in the progression of many malignant tumors. Nevertheless, the function of the TRIM31/AKT pathway in oral squamous cell carcinoma (OSCC) remains elusive. Here, immunohistochemistry analysis of human OSCC tissue microarrays indicated significantly higher levels of TRIM31 and phosphorylated AKT (p-AKT) in OSCC tumors than in adjacent tissue samples. Also, we detected a positive association between TRIM31 expression and clinical OSCC development. In in vitro studies, TRIM31 knockdown severely impaired OSCC cell growth, invasion, and migration. By contrast, TRIM31 overexpression improved these cell behaviors, while subsequent AKT inhibition abrogated the effect. In vivo tumorigenesis experiments using nude mice also validated the effects of TRIM31/AKT signaling in tumor growth. Furthermore, TRIM31 upregulation facilitated glucose uptake, as well as lactate and adenosine triphosphate production of OSCC cells, while such positive effects on glycolysis and malignant cell phenotypes were reversed by treatment with AKT or glycolysis inhibitors. In conclusion, TRIM31 may improve OSCC progression by enhancing AKT phosphorylation and subsequent glycolysis. Hence, TRIM31 has the potential as a treatment target in OSCC.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Humanos , Camundongos , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Glicólise , Camundongos Nus , Neoplasias Bucais/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genéticaRESUMO
Dye and nitro-compound pollution has become a significant issue worldwide. The adsorption and degradation of dyes and nitro-compounds have recently become important areas of study. Different methods, such as precipitation, flocculation, ultra-filtration, ion exchange, coagulation, and electro-catalytic degradation have been adopted for the adsorption and degradation of these organic pollutants. Apart from these methods, adsorption, photocatalytic degradation, and chemical degradation are considered the most economical and efficient to control water pollution from dyes and nitro-compounds. In this review, different kinds of dyes and nitro-compounds, and their adverse effects on aquatic organisms and human beings, were summarized in depth. This review article covers the comprehensive analysis of the adsorption of dyes over different materials (porous polymer, carbon-based materials, clay-based materials, layer double hydroxides, metal-organic frameworks, and biosorbents). The mechanism and kinetics of dye adsorption were the central parts of this study. The structures of all the materials mentioned above were discussed, along with their main functional groups responsible for dye adsorption. Removal and degradation methods, such as adsorption, photocatalytic degradation, and chemical degradation of dyes and nitro-compounds were also the main aim of this review article, as well as the materials used for such degradation. The mechanisms of photocatalytic and chemical degradation were also explained comprehensively. Different factors responsible for adsorption, photocatalytic degradation, and chemical degradation were also highlighted. Advantages and disadvantages, as well as economic cost, were also discussed briefly. This review will be beneficial for the reader as it covers all aspects of dye adsorption and the degradation of dyes and nitro-compounds. Future aspects and shortcomings were also part of this review article. There are several review articles on all these topics, but such a comprehensive study has not been performed so far in the literature.
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To compare the pancreatic proteomics and autophagy between Rehmanniae Radix-and Rehmanniae Radix Praeparata-treated mice with type 2 diabetes mellitus(T2DM). The T2DM mouse model was established by high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days). The mice were then randomly assigned into a control group, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) catalpol groups, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) 5-hydroxymethyl furfuraldehyde(5-HMF) groups, and a metformin(250 mg·kg~(-1)) group. In addition, a normal group was also set and each group included 8 mice. The pancreas was collected after four weeks of administration and proteomics tools were employed to study the effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on protein expression in the pancreas of T2DM mice. The expression levels of proteins involved in autophagy, inflammation, and oxidative stress response in the pancreatic tissues of T2DM mice were determined by western blotting, immunohistochemical assay, and transmission electron microscopy. The results showed that the differential proteins between the model group and Rehmanniae Radix/Rehmanniae Radix Prae-parata group were enriched in 7 KEGG pathways, such as autophagy-animal, which indicated that the 7 pathways may be associated with T2DM. Compared with the control group, drug administration significantly up-regulated the expression levels of beclin1 and phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR and down-regulated those of the inflammation indicators, Toll-like receptor-4(TLR4) and Nod-like receptor protein 3(NLRP3), in the pancreas of T2DM mice, and Rehmanniae Radix showed better performance. In addition, the expression levels of inducible nitric oxide synthase(iNOS), nuclear factor erythroid 2-related factor 2(Nrf2), and heine oxygenase-1(HO-1) in the pancreas of T2DM mice were down-regulated after drug administration, and Rehmanniae Radix Praeparata demonstrated better performance. The results indicate that both Rehmanniae Radix and Rehmanniae Radix Praeparata can alleviate the inflammatory symptoms, reduce oxidative stress response, and increase the autophagy level in the pancreas of T2DM mice, while they exert the effect on different autophagy pathways.
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Diabetes Mellitus Tipo 2 , Camundongos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Estreptozocina/farmacologia , Dieta Hiperlipídica/efeitos adversos , Proteômica , Inflamação , Serina-Treonina Quinases TOR , Autofagia , MamíferosRESUMO
Skeleton and teeth are important biological samples. Due to their special structure and strong ability to resist degradation, they are ideal biological materials to retain DNA under natural condition. In many cases, such as historical figure identification, aged skeleton and teeth are usually the only biological samples. However, their DNA is in a state of trace, damage and degradation to different degrees, which requires special experimental treatment to achieve identification. This paper reviews the sample selection, DNA extraction, DNA enrichment and analysis approaches based on relevant research reports in recent years, aiming to promote the further development and improvement of the aged skeleton and teeth identification system.
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Restos Mortais , Dente , Humanos , Idoso , DNA/genética , DNA/análise , Impressões Digitais de DNA , Análise de Sequência de DNARESUMO
Anthrones and analogues are structural cores shared by diverse pharmacologically active natural and synthetic compounds. The sp2 -rich nature imposes inherent obstruction to introduce stereogenic element onto the tricyclic aromatic backbone. In our pursuit to expand the chemical space of axial chirality, a novel type of axially chiral anthrone-derived skeleton was discovered. This work establishes oxime ether as suitable functionality to furnish axial chirality on symmetric anthrone skeletons through stereoselective condensation of the carbonyl entity with long-range chirality control. The enantioenriched anthrones could be elaborated into dibenzo-fused seven-membered N-heterocycles containing well-defined stereogenic center via Beckmann rearrangement with axial-to-point chirality conversion.
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Antracenos , Estereoisomerismo , CatáliseRESUMO
Platinum-based atomically ordered alloys (i.e., intermetallic compounds) have distinct advantages over disordered solid solution counterparts in boosting the cathodic oxygen-reduction reaction (ORR) in proton-exchange-membrane fuel cells. Nevertheless, the pivotal role of ordering degree of intermetallic catalysts in promoting ORR performance has been ignored heavily so far, probably owing to the lack of synthetic routes for controlling the ordering degree, especially for preparing highly ordered intermetallic catalysts. Herein, a family of intermetallic PtFe catalysts with similar particle size of 3-4 nm but varied ordering degree in a wide range of 10-70% are prepared. After constructing the PtFe/Pt core/shell structure with around 3 Pt-layer skin, a positive correlation between the ordering degree of the intermetallic catalysts and their ORR activity and durability is identified. Notably, the highly ordered PtFe/Pt catalyst exhibits a high mass activity of 0.92 A mgPt -1 at 0.9 ViR-corrected as cathode catalyst in H2 -O2 fuel cell, with only 24% loss after accelerated durability tests. The ordering degree-dependent performance can be ascribed to the compressive strain effect induced by the intermetallic PtFe core with smaller lattice parameters, and the more thermodynamically stable intermetallic structure compared to disordered alloys.
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As the most abundant d-amino acid (DAA) in the ocean, d-alanine (d-Ala) is a key component of peptidoglycan in the bacterial cell wall. However, the underlying mechanisms of bacterial metabolization of d-Ala through the microbial food web remain largely unknown. In this study, the metabolism of d-Ala by marine bacterium Pseudoalteromonas sp. strain CF6-2 was investigated. Based on genomic, transcriptional, and biochemical analyses combined with gene knockout, d-Ala aminotransferase was found to be indispensable for the catabolism of d-Ala in strain CF6-2. Investigation on other marine bacteria also showed that d-Ala aminotransferase gene is a reliable indicator for their ability to utilize d-Ala. Bioinformatic investigation revealed that d-Ala aminotransferase sequences are prevalent in genomes of marine bacteria and metagenomes, especially in seawater samples, and Gammaproteobacteria represents the predominant group containing d-Ala aminotransferase. Thus, Gammaproteobacteria is likely the dominant group to utilize d-Ala via d-Ala aminotransferase to drive the recycling and mineralization of d-Ala in the ocean. IMPORTANCE As the most abundant d-amino acid in the ocean, d-Ala is a component of the marine DON (dissolved organic nitrogen) pool. However, the underlying mechanism of bacterial metabolization of d-Ala to drive the recycling and mineralization of d-Ala in the ocean is still largely unknown. The results in this study showed that d-Ala aminotransferase is specific and indispensable for d-Ala catabolism in marine bacteria and that marine bacteria containing d-Ala aminotransferase genes are predominantly Gammaproteobacteria widely distributed in global oceans. This study reveals marine d-Ala-utilizing bacteria and the mechanism of their metabolization of d-Ala. The results shed light on the mechanisms of recycling and mineralization of d-Ala driven by bacteria in the ocean, which are helpful in understanding oceanic microbial-mediated nitrogen cycle.
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Pseudoalteromonas , Alanina/metabolismo , Pseudoalteromonas/genética , Pseudoalteromonas/metabolismo , Água do Mar/microbiologia , Transaminases/genéticaRESUMO
BACKGROUND: TaqMan probe-based real-time PCR (qPCR/RT-qPCR) has been widely used in various fields because of its high sensitivity and specificity. However, TaqMan probes are associated with a relatively higher background signal, and hence negatively affect the detection results. METHODS: Double-stranded probes (DSPs) were designed for the high sensitive detection of hepatitis B virus (HBV) DNA and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using qPCR/RT-qPCR. Old DSPs (ODSPs) consist of different lengths of positive and negative strands with complementary oligonucleotides. We systematically optimized ODSPs length, the free energy of hybridization (ΔG) between complementary oligonucleotides, and the length of sticky ends, and the novel DSPs performances were evaluated in comparison with other types of probes. RESULTS: By using similar length positive and negative strands, controlling ΔG between complementary oligonucleotides to approximately -30 kcal/mol, and maintaining the sticky end length at 4-6 nt, the analytical performances of DSPs were significantly improved. Compared with other types of probes, DSPs are advantageous in fluorescence signal intensity and sensitivity. CONCLUSION: DSPs can further improve the detection sensitivity and the detection rate of low-concentration samples in molecular diagnosis.
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COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Humanos , Oligonucleotídeos , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2/genética , Sensibilidade e EspecificidadeRESUMO
Using a visible-light photoredox catalysis strategy with household decorative blue LEDs and the additives Et3N and DIPEA, as well as the subsequent hydrolysis sequence, a mild one-pot process for the direct transformation of nitroalkanes to the corresponding ketones and aldehydes, constituting a Nef-like reaction, has been developed. It is worth noting that by using an appropriate photocatalyst (e.g., [Ir(dtbbpy)(ppy)2]PF6) and the extra additive Et3N with the combination of DIPEA and Mg(ClO4)2 in i-PrOH (instead of CH3CN), the transformation of nitroalkanes to the corresponding oximes, rather than nitrones, can be markedly more effective. The oximes can then be hydrolyzed to ketones by reaction with CuCl2·2H2O in a pH 7 buffer solution. This process is appealing because of the benefits of efficient conversion, mild conditions, high yields, and general applicability to compounds with a wide range of labile functional groups.
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Aldeídos , Cetonas , Aldeídos/química , Alcanos , Catálise , Hidrólise , Cetonas/química , Estrutura Molecular , Nitrocompostos/química , Oximas/químicaRESUMO
BACKGROUND: Currently, it remains unclear whether ß-blockers or nondihydropyridine calcium channel blockers are preferred for the acute management of atrial fibrillation (AF). OBJECTIVE: The objective of this study was to compare the efficacy and safety of intravenous (IV) metoprolol and diltiazem for rate control. METHODS: This was a single-center, retrospective cohort study of patients who presented to the emergency department between 2015 and 2019 with AF with rapid ventricular rate (RVR) and received IV metoprolol or diltiazem. The primary outcome was the percentage of patients who achieved rate control (defined as heart rate < 100 beats per minute). Secondary outcomes included time to rate control, percentage of patients requiring additional agents for rate control, and incidence of cardioversion, bradycardia, and hypotension. RESULTS: A total of 200 patients were included in this study. Rate control was achieved in 35% and 41% of the metoprolol and diltiazem groups, respectively (P = 0.38). Mean time to rate control was not significantly different between the metoprolol and diltiazem groups (35 vs 21 minutes, P = 0.23). One patient developed hypotension, no patient developed bradycardia, and 4 patients required electric cardioversion. No adverse events were observed in patients with ejection fraction ≤40%. CONCLUSION AND RELEVANCE: There was no difference in the achievement of rate control between IV metoprolol and diltiazem. This is the largest study to date comparing the two classes of agents for acute rate control in AF. No patient-specific factors were identified that would influence the preferential use of one medication over the other.
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Fibrilação Atrial , Hipotensão , Fibrilação Atrial/complicações , Bradicardia/induzido quimicamente , Bloqueadores dos Canais de Cálcio/efeitos adversos , Diltiazem/efeitos adversos , Frequência Cardíaca , Humanos , Hipotensão/induzido quimicamente , Hipotensão/tratamento farmacológico , Metoprolol/efeitos adversos , Estudos RetrospectivosRESUMO
The resource utilization of spent alkaline Zn-Mn batteries (S-AZMB) has always been a hot issue in the field of energy regeneration and environmental protection. The cumbersome and complicated purification process is the reason for their limited recycling. Not long ago, we proved that unpurified S-AZMB can be used directly: construct a Z-scheme photocatalytic system by combining with commercial TiO2 through high-temperature calcination. In order for this finding to be truly adopted by the application market, the high energy consumption calcination process needs to be improved urgently. In this work, we explore the temperature dependence of performance for the composite photocatalyst (TiO2@S-AZMB). A series of experimental results confirm that lowering the calcination temperature not only conducive to improving the separation efficiency of photogenerated electron-hole pairs, but also can significantly improve the environmental adaptability of the catalyst. Specifically, the catalyst synthesized by calcination temperature at 200 °C exhibits higher toluene removal efficiency than that at 500 °C under different initial concentration of pollutants, relative humidity, light intensity and oxygen content. This study not only further improves the photocatalytic performance of the composite catalyst, but also accords with the idea of energy saving and emission reduction, which provides more space for the possibility of recycling S-AZMB.