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1.
Proc Natl Acad Sci U S A ; 121(13): e2315531121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38498704

RESUMO

Mating type (sex) plays a crucial role in regulating sexual reproduction in most extant eukaryotes. One of the functions of mating types is ensuring self-incompatibility to some extent, thereby promoting genetic diversity. However, heterothallic mating is not always the best mating strategy. For example, in low-density populations or specific environments, such as parasitic ones, species may need to increase the ratio of potential mating partners. Consequently, many species allow homothallic selfing (i.e., self-fertility or intraclonal mating). Throughout the extensive evolutionary history of species, changes in environmental conditions have influenced mating strategies back and forth. However, the mechanisms through which mating-type recognition regulates sexual reproduction and the dynamics of mating strategy throughout evolution remain poorly understood. In this study, we show that the Cip1 protein is responsible for coupling sexual reproduction initiation to mating-type recognition in the protozoal eukaryote Tetrahymena thermophila. Deletion of the Cip1 protein leads to the loss of the selfing-avoidance function of mating-type recognition, resulting in selfing without mating-type recognition. Further experiments revealed that Cip1 is a regulatory subunit of the Cdk19-Cyc9 complex, which controls the initiation of sexual reproduction. These results reveal a mechanism that regulates the choice between mating and selfing. This mechanism also contributes to the debate about the ancestral state of sexual reproduction.


Assuntos
Fertilidade , Reprodução , Reprodução/genética , Eucariotos/genética , Genes Fúngicos Tipo Acasalamento
2.
Genes Dev ; 33(5-6): 348-364, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30808657

RESUMO

RNAi and Polycomb repression play evolutionarily conserved and often coordinated roles in transcriptional silencing. Here, we show that, in the protozoan Tetrahymena thermophila, germline-specific internally eliminated sequences (IESs)-many related to transposable elements (TEs)-become transcriptionally activated in mutants deficient in the RNAi-dependent Polycomb repression pathway. Germline TE mobilization also dramatically increases in these mutants. The transition from noncoding RNA (ncRNA) to mRNA production accompanies transcriptional activation of TE-related sequences and vice versa for transcriptional silencing. The balance between ncRNA and mRNA production is potentially affected by cotranscriptional processing as well as RNAi and Polycomb repression. We posit that interplay between RNAi and Polycomb repression is a widely conserved phenomenon, whose ancestral role is epigenetic silencing of TEs.


Assuntos
Elementos de DNA Transponíveis/genética , Proteínas do Grupo Polycomb/genética , Proteínas de Protozoários/genética , Interferência de RNA , Tetrahymena thermophila/genética , Ativação Transcricional/genética , Epigênese Genética , Inativação Gênica , Mutação , RNA Mensageiro/genética , RNA não Traduzido/genética
3.
Nucleic Acids Res ; 52(D1): D747-D755, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37930867

RESUMO

Protists, a highly diverse group of microscopic eukaryotic organisms distinct from fungi, animals and plants, exert crucial roles within the earth's biosphere. However, the genomes of only a small fraction of known protist species have been published and made publicly accessible. To address this constraint, the Protist 10 000 Genomes Project (P10K) was initiated, implementing a specialized pipeline for single-cell genome/transcriptome assembly, decontamination and annotation of protists. The resultant P10K database (https://ngdc.cncb.ac.cn/p10k/) serves as a comprehensive platform, collating and disseminating genome sequences and annotations from diverse protist groups. Currently, the P10K database has incorporated 2959 genomes and transcriptomes, including 1101 newly sequenced datasets by P10K and 1858 publicly available datasets. Notably, it covers 45% of the protist orders, with a significant representation (53% coverage) of ciliates, featuring nearly a thousand genomes/transcriptomes. Intriguingly, analysis of the unique codon table usage among ciliates has revealed differences compared to the NCBI taxonomy system, suggesting a need to revise the codon tables used for these species. Collectively, the P10K database serves as a valuable repository of genetic resources for protist research and aims to expand its collection by incorporating more sequenced data and advanced analysis tools to benefit protist studies worldwide.


Assuntos
Bases de Dados Genéticas , Eucariotos , Fungos , Genoma , Animais , Códon , Eucariotos/genética , Fungos/genética , Plantas/genética
4.
J Proteome Res ; 23(5): 1689-1701, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565891

RESUMO

Cyanobacteria are the oldest prokaryotic photoautotrophic microorganisms and have evolved complicated post-translational modification (PTM) machinery to respond to environmental stress. Lysine 2-hydroxyisobutyrylation (Khib) is a newly identified PTM that is reported to play important roles in diverse biological processes, however, its distribution and function in cyanobacteria have not been reported. Here, we performed the first systematic studies of Khib in a model cyanobacterium Synechococcus sp. strain PCC 7002 (Syn7002) using peptide prefractionation, pan-Khib antibody enrichment, and high-accuracy mass spectrometry (MS) analysis. A total of 1875 high-confidence Khib sites on 618 proteins were identified, and a large proportion of Khib sites are present on proteins in the cellular metabolism, protein synthesis, and photosynthesis pathways. Using site-directed mutagenesis and functional studies, we showed that Khib of glutaredoxin (Grx) affects the efficiency of the PS II reaction center and H2O2 resistance in Syn7002. Together, this study provides novel insights into the functions of Khib in cyanobacteria and suggests that reversible Khib may influence the stress response and photosynthesis in both cyanobacteria and plants.


Assuntos
Lisina , Processamento de Proteína Pós-Traducional , Synechococcus , Lisina/metabolismo , Synechococcus/metabolismo , Synechococcus/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Peróxido de Hidrogênio/metabolismo , Glutarredoxinas/metabolismo , Glutarredoxinas/genética , Complexo de Proteína do Fotossistema II/metabolismo , Complexo de Proteína do Fotossistema II/genética , Mutagênese Sítio-Dirigida , Fotossíntese , Cianobactérias/metabolismo , Cianobactérias/genética , Espectrometria de Massas
5.
Lancet ; 401(10380): 928-938, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36871573

RESUMO

BACKGROUND: Effectiveness of a non-physician community health-care provider-led intensive blood pressure intervention on cardiovascular disease has not been established. We aimed to test the effectiveness of such an intervention compared with usual care on risk of cardiovascular disease and all-cause death among individuals with hypertension. METHODS: In this open-label, blinded-endpoint, cluster-randomised trial, we recruited individuals aged at least 40 years with an untreated systolic blood pressure of at least 140 mm Hg or a diastolic blood pressure of at least 90 mm Hg (≥130 mm Hg and ≥80 mm Hg for those at high risk for cardiovascular disease or if currently taking antihypertensive medication). We randomly assigned (1:1) 326 villages to a non-physician community health-care provider-led intervention or usual care, stratified by provinces, counties, and townships. In the intervention group, trained non-physician community health-care providers initiated and titrated antihypertensive medications according to a simple stepped-care protocol to achieve a systolic blood pressure goal of less than 130 mm Hg and diastolic blood pressure goal of less than 80 mm Hg with supervision from primary care physicians. They also delivered discounted or free antihypertensive medications and health coaching for patients. The primary effectiveness outcome was a composite outcome of myocardial infarction, stroke, heart failure requiring hospitalisation, and cardiovascular disease death during the 36-month follow-up in the study participants. Safety was assessed every 6 months. This trial is registered with ClinicalTrials.gov, NCT03527719. FINDINGS: Between May 8 and Nov 28, 2018, we enrolled 163 villages per group with 33 995 participants. Over 36 months, the net group difference in systolic blood pressure reduction was -23·1 mm Hg (95% CI -24·4 to -21·9; p<0·0001) and in diastolic blood pressure reduction, it was -9·9 mm Hg (-10·6 to -9·3; p<0·0001). Fewer patients in the intervention group than the usual care group had a primary outcome (1·62% vs 2·40% per year; hazard ratio [HR] 0·67, 95% CI 0·61-0·73; p<0·0001). Secondary outcomes were also reduced in the intervention group: myocardial infarction (HR 0·77, 95% CI 0·60-0·98; p=0·037), stroke (0·66, 0·60-0·73; p<0·0001), heart failure (0·58, 0·42-0·81; p=0·0016), cardiovascular disease death (0·70, 0·58-0·83; p<0·0001), and all-cause death (0·85, 0·76-0·95; p=0·0037). The risk reduction of the primary outcome was consistent across subgroups of age, sex, education, antihypertensive medication use, and baseline cardiovascular disease risk. Hypotension was higher in the intervention than in the usual care group (1·75% vs 0·89%; p<0·0001). INTERPRETATION: The non-physician community health-care provider-led intensive blood pressure intervention is effective in reducing cardiovascular disease and death. FUNDING: The Ministry of Science and Technology of China and the Science and Technology Program of Liaoning Province, China.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Hipertensão , Hipotensão , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Doenças Cardiovasculares/complicações , Pressão Sanguínea , Anti-Hipertensivos/uso terapêutico , Saúde Pública , Hipertensão/tratamento farmacológico , Hipertensão/complicações , Hipotensão/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico
6.
BMC Med ; 22(1): 258, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902731

RESUMO

BACKGROUND: The 2018/2023 ESC/ESH Guidelines underlined a gap how baseline cardiovascular disease (CVD) risk predicted blood pressure (BP) lowering benefits. Further, 2017 ACC/AHA Guideline and 2021 WHO Guideline recommended implementation studies about intensive BP control. Now, to bridge these guideline gaps, we conducted a post hoc analysis to validate whether the baseline CVD risk influences the effectiveness of the intensive BP control strategy, which was designed by China Rural Hypertension Control Project (CRHCP). METHODS: This is a post hoc analysis of CRHCP, among which participants were enrolled except those having CVD history, over 80 years old, or missing data. Subjects were stratified into quartiles by baseline estimated CVD risk and then grouped into intervention and usual care group according to original assignment in CRHCP. Participants in the intervention group received an integrated, multi-faceted treatment strategy, executed by trained non-physician community health-care providers, aiming to achieve a BP target of < 130/80 mmHg. Cox proportional-hazards models were used to estimate the hazard ratios of outcomes for intervention in each quartile, while interaction effect between intervention and estimated CVD risk quartiles was additionally assessed. The primary outcome comprised myocardial infarction, stroke, hospitalization for heart failure, or CVD deaths. RESULTS: Significant lower rates of primary outcomes for intervention group compared with usual care for each estimated CVD risk quartile were reported. The hazard ratios (95% confidence interval) in the four quartiles (from Q1 to Q4) were 0.59 (0.40, 0.87), 0.54 (0.40, 0.72), 0.72 (0.57, 0.91) and 0.65 (0.53, 0.80), respectively (all Ps < 0.01). There's no significant difference of hazard ratios by intervention across risk quartiles (P for interaction = 0.370). Only the relative risk of hypotension, not symptomatic hypotension, was elevated in the intervention group among upper three quartiles. CONCLUSIONS: Intensive BP lowering strategy designed by CRHCP group was effective and safe in preventing cardiovascular events independent of baseline CVD risk. TRIAL REGISTRATION: The trial is registered with ClinicalTrials.gov, NCT03527719.


Assuntos
Doenças Cardiovasculares , Hipertensão , Humanos , Masculino , Feminino , China/epidemiologia , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Pessoa de Meia-Idade , Idoso , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/epidemiologia , Pressão Sanguínea/fisiologia , População Rural , Anti-Hipertensivos/uso terapêutico , Resultado do Tratamento , Fatores de Risco de Doenças Cardíacas
7.
Mol Phylogenet Evol ; 197: 108110, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38768875

RESUMO

Ciliophora, an exceptionally diverse lineage of unicellular eukaryotes, exhibits a remarkable range of species richness across classes in the ciliate Tree of Life. In this study, we have acquired transcriptome and genome data from 40 representative species in seven ciliate classes. Utilizing 247 genes and 105 taxa, we devised a comprehensive phylogenomic tree for Ciliophora, encompassing over 60 % of orders and constituting the most extensive dataset of ciliate species to date. We established a robust phylogenetic framework that encompasses ambiguous taxa and the major classes within the phylum. Our findings support the monophyly of each of two subphyla (Postciliodesmatophora and Intramacronucleata), along with three subclades (Protocruzia, CONTHREEP, and SAPML) nested within Intramacronucleata, and elucidate evolutionary positions among the major classes within the phylum. Drawing on the robust ciliate Tree of Life and three constraints, we estimated the radiation of Ciliophora around 1175 Ma during the middle of the Proterozoic Eon, and most of the ciliate classes diverged from their sister lineage during the latter half of this period. Additionally, based on the time-calibrated tree and species richness pattern, we investigated net diversification rates of Ciliophora and its classes. The global net diversification rate for Ciliophora was estimated at 0.004979 species/Ma. Heterogeneity in net diversification rates was evident at the class level, with faster rates observed in Oligohymenophorea and Spirotrichea than other classes within the subclades CONTHREEP and SAPML, respectively. Notably, our analysis suggests that variations in net diversification rates, rather than clade ages, appear to contribute to the differences in species richness in Ciliophora at the class level.


Assuntos
Cilióforos , Filogenia , Cilióforos/genética , Cilióforos/classificação , Transcriptoma , Evolução Molecular , Especiação Genética
8.
Mol Pharm ; 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39432317

RESUMO

Despite the potent immunoadjuvant properties of mevalonate pathway inhibitors, their application is constrained by poor solubility and instability. In this study, we developed a cationic nanoparticle-stabilized Pickering emulsion loaded with lovastatin (Lov-PPE), using polyethylenimine (PEI)-modified PLGA nanoparticles and squalene as carriers. The system was prepared and tested by evaluating the physicochemical properties and adjuvant efficacy of the Lov-PPE. Lov-PPE/O demonstrated good particle size distribution and zeta potential, with an adsorption efficiency of up to 73.07%. The immunization results showed that Lov-PPE/O significantly promoted the production of OVA-specific IgG antibodies, activated CD4+ and CD8+ T cells, and induced a strong mixed Th1/2 immune response. Additionally, safety assessments indicated that Lov-PPE/O has good in vivo safety. This study demonstrates that the PEI-modified lovastatin PLGA nanoparticle Pickering emulsion (Lov-PPE) is an effective vaccine adjuvant capable of significantly enhancing humoral and cellular immune responses while possessing good safety, offering a new strategy for vaccine formulation development.

9.
Diabetes Obes Metab ; 26(1): 373-384, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37920887

RESUMO

AIM: To investigate the sex-specific causality of body compositions in type 2 diabetes and related glycaemic traits using Mendelian randomization (MR). MATERIALS AND METHODS: We leveraged sex-specific summary-level statistics from genome-wide association studies for three adipose deposits adjusted for body mass index and height, including abdominal subcutaneous adipose tissue, visceral adipose tissue (VATadj) and gluteofemoral adipose tissue (GFATadj), measured by MRI (20 038 women; 19 038 men), and fat mass-adjusted appendicular lean mass (ALMadj) (244 730 women; 205 513 men) in the UK Biobank. Sex-specific statistics of type 2 diabetes were from the Diabetes Genetics Replication and Meta-analysis Consortium and those for fasting glucose and insulin were from the Meta-analyses of Glucose and Insulin-related Traits Consortium. Univariable and multivariable MR (MVMR) were performed. We also performed MR analyses of anthropometric traits and genetic association analyses using individual-level data of body composition as validation. RESULTS: Univariable MR analysis showed that, in women, higher GFATadj and ALMadj exerted a causally protective effect on type 2 diabetes (GFATadj: odds ratio [OR] 0.59, 95% confidence interval [CI; 0.50, 0.69]; ALMadj: OR 0.84, 95% CI [0.77, 0.91]) and VATadj to be riskier in glycaemic traits. MVMR showed that GFATadj retained a robust effect on type 2 diabetes (OR 0.57, 95% CI [0.42, 0.77]; P = 2.6 × 10-4 ) in women, while it was nominally significant in men (OR 0.58, 95% CI [0.35, 0.96]; P = 3.3 × 10-2 ), after adjustment for ASATadj and VATadj. MR analyses of anthropometric measures and genetic association analyses of glycaemic traits confirmed the results. CONCLUSIONS: Body composition has a sex-specific effect on type 2 diabetes, and higher GFATadj has an independent protective effect on type 2 diabetes in both sexes.


Assuntos
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Feminino , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Índice de Massa Corporal , Adiposidade/genética , Insulina/genética , Imageamento por Ressonância Magnética , Glucose , Polimorfismo de Nucleotídeo Único , Estudos Observacionais como Assunto
10.
Ecotoxicol Environ Saf ; 275: 116258, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38547732

RESUMO

Biomethylation is an effective means of arsenic detoxification by organisms living in aquatic environments. Ciliated protozoa (including Tetrahymena species) play an important role in the biochemical cycles of aquatic ecosystems and have a potential application in arsenic biotransformation. This study compared arsenic tolerance, accumulation, methylation, and efflux in 11 Tetrahymena species. Nineteen arsenite (As(III)) S-adenosylmethionine (SAM) methyltransferase (arsM) genes, of which 12 are new discoveries, were identified, and protein sequences were studied. We then constructed recombinant cell lines based on the Tetrahymena thermophila (T. thermophila) wild-type SB210 strain and expressed each of the 19 arsM genes under the control of the metal-responsive the MTT1 promoter. In the presence of Cd2+ and As(V), expression of the arsM genes in the recombinant cell lines was much higher than in the donor species. Evaluation of the recombinant cell line identified one with ultra-high arsenic methylation enzyme activity, significantly higher arsenic methylation capacity and much faster methylation rate than other reported arsenic methylated organisms, which methylated 89% of arsenic within 6.5 h. It also had an excellent capacity for the arsenic detoxification of lake water containing As(V), 56% of arsenic was methylated at 250 µg/L As(V) in 48 h. This study has made a significant contribution to our knowledge on arsenic metabolism in protozoa and demonstrates the great potential to use Tetrahymena species in the arsenic biotransformation of aquatic environments.


Assuntos
Arsênio , Tetrahymena thermophila , Arsênio/metabolismo , Ecossistema , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Biotransformação , Tetrahymena thermophila/genética , Tetrahymena thermophila/metabolismo
11.
World J Microbiol Biotechnol ; 40(4): 132, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470533

RESUMO

Lactococcus garvieae (L. garvieae) is a pathogenic bacterium that is Gram-positive and catalase-negative (GPCN), and it is capable of growing in a wide range of environmental conditions. This bacterium is associated with significant mortality and losses in fisheries, and there are concerns regarding its potential as a zoonotic pathogen, given its presence in cattle and dairy products. While we have identified and characterized virulent strains of L. garvieae through phenotyping and molecular typing studies, their impact on mammary tissue remains unknown. This study aims to investigate the pathogenicity of strong and weak virulent strains of L. garvieae using in vivo mouse models. We aim to establish MAC-T cell model to examine potential injury caused by the strong virulent strain LG41 through the TLR2/NLRP3/NF-kB pathway. Furthermore, we assess the involvement of NLRP3 inflammasome-mediated pyroptosis in dairy mastitis by silencing NLRP3. The outcomes of this study will yield crucial theoretical insights into the potential mechanisms involved in mastitis in cows caused by the L. garvieae-induced inflammatory response in MAC-T cells.


Assuntos
Inflamassomos , Mastite , Humanos , Feminino , Animais , Bovinos , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Linfócitos T/metabolismo , Lactococcus/metabolismo , Mastite/microbiologia , Mastite/veterinária , Inflamação
12.
Chemistry ; 29(35): e202300449, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37070968

RESUMO

Aromatic ring fusion on BODIPY core can effectively tune its electronic property, and red-shift its absorption and emission wavelength. In this work, we report that a one-pot Pd(II) catalyzed multiple C-H activation to access acenaphtho[b]-fused BODIPYs though the reaction of α,ß-unsubstituted-BODIPYs and 1,8-dibromonaphthalenes. These newly synthesized acenaphtho[b]-fused BODIPYs revealed intensified deep red absorptions (639-669 nm) and emissions (643-683 nm), with high fluorescence quantum yields (0.53-0.84) in dichloromethane. Notably, these acenaphtho[b]-fused BODIPYs exhibited well-defined self-aggregation behavior in water/THF mixture, and for instance, the absorption of 3 a was red-shifted by 53 nm to 693 nm after forming aggregates.


Assuntos
Corantes Fluorescentes , Paládio , Paládio/química , Corantes Fluorescentes/química , Compostos de Boro/química , Catálise
13.
Chemistry ; 29(14): e202203832, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36650103

RESUMO

Near-infrared (NIR) fluorophores with characteristics such as deep tissue penetration, minimal damage to the biological samples, and low background interference, are highly sought-after materials for in vivo and deep-tissue fluorescence imaging. Herein, series of 3-pyrrolylBODIPY derivatives and 3,5-dipyrrolylBODIPY derivatives have been prepared by a facile regioselective nucleophilic aromatic substitution reaction (SN Ar) on 3,5-halogenated BODIPY derivatives (3,5-dibromo or 2,3,5,6-tetrachloroBODIPYs) with pyrroles. The installation of a pyrrolic unit onto the 3-position of the BODIPY chromophore leads to a dramatic red shift of both the absorption (up to 160 nm) and the emission (up to 260 nm) in these resultant 3-pyrrolylBODIPYs with respect to that of the BODIPY chromophore. Their further 5-positional functionalization provides a facile way to fine tune their photophysical properties, and these resulting dipyrrolylBODIPYs and functionalized pyrrolylBODIPYs show strong absorption in the deep red-to-NIR regions (595-684 nm) and intense NIR fluorescence emission (650-715 nm) in dichloromethane. To demonstrate the applicability of these functionalized pyrrolylBODIPYs as NIR fluorescent probes for cell imaging, pyrrolylBODIPY 6 a containing mitochondrion-targeting butyltriphenylphosphonium cationic species was also prepared. It selectively localized in mitochondria of HeLa cells, with low cytotoxicity and intense deep red fluorescence emission.


Assuntos
Compostos de Boro , Corantes Fluorescentes , Humanos , Células HeLa , Fluorescência
14.
J Eukaryot Microbiol ; 70(2): e12950, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36177660

RESUMO

The Peritrichia is a speciose and morphologically distinctive assemblage of ciliated protists that was first observed by Antonie van Leeuwenhoek over 340 years ago. In the last two decades, the phylogenetic relationships of this group have been increasingly debated as morphological and molecular analyses have generated contrasting conclusions, mainly owing to limited sampling. In the present study, we performed expanded phylogenetic analyses of 152 sessilid peritrichs collected from 14 different provinces of China and 141 SSU rDNA peritrich sequences from GenBank. The results of the analyses revealed new divergent relationships between and within major clades that challenge the morphological classification of this group including, (1) the recovery of four major phylogenetically divergent clades in the monophyletic order Sessilida, (2) aboral structures such as the stalk and spasmoneme were evolutionary labile, (3) the stalk or/and spasmoneme was lost in each divergent clade indicating that parallel evolution occurred in sessilid peritrichs and (4) the life cycle and habit drive the diversity of aboral structures as well as diversification and evolution in peritrichs.


Assuntos
Cilióforos , Oligoimenóforos , Filogenia , DNA de Protozoário/genética , DNA Ribossômico/genética
15.
Phys Chem Chem Phys ; 25(37): 25177-25190, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37712428

RESUMO

With the explosion of data-centric applications, new in-memory computing technologies, based on nonvolatile memory devices, have become competitive due to their merged logic-memory functionalities. Herein, employing first-principles quantum transport simulation, we theoretically investigate for the first time the electronic and contact properties of two types of monolayer (ML)-MoS2 ferroelectric field-effect transistors (FeFETs) integrated with ferroelectric BiAlO3(0001) (BAO(0001)) polar surfaces. Our study finds that the interfacial properties of the investigated partial FeFET devices are highly tunable by switching the electric polarization of the ferroelectric BAO(0001) dielectric. Specifically, the transition from quasi-Ohmic to the Schottky contact, as well as opposite contact polarity of respective n-type and p-type Schottky contact under two polarization states can be obtained, suggesting their superior performance metrics in terms of nonvolatile information storage. In addition, due to the feature of (quasi-)Ohmic contact in some polarization states, the explored FeFET devices, even when operating in the regular field-effect transistor (FET) mode, can be extremely significant in realizing a desirable low threshold voltage and interfacial contact resistance. In conjunction with the formed van der Waals (vdW) interfaces in ML-MoS2/ferroelectric systems with an interlayer, the proposed FeFETs are expected to provide excellent device performance with regard to cycling endurance and memory density.

16.
Phys Chem Chem Phys ; 25(48): 33130-33140, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38047441

RESUMO

In recent years, α-In2Se3 has attracted great attention in miniaturizing nonvolatile random memory devices because of its room temperature ferroelectricity and atomic thickness. In this work, we construct two-dimensional (2D) van der Waals (vdW) heterostructures α-In2Se3/MoS2 with different ferroelectric polarization and design a 2D graphene (Gr)/In2Se3/MoS2/Gr ferroelectric tunnel junction (FTJ) with the symmetric electrodes. Our calculations show that the band alignment of the heterostructures can be changed from type-I to type-II accompanied by the reversal of the ferroelectric polarization of In2Se3. Furthermore, the ferroelectricity persists in Gr/In2Se3/MoS2/Gr vdW FTJs, and the presence of dielectric layer MoS2 in the FTJs enables the effective modulation of the tunneling barrier by altering the ferroelectric polarization of α-In2Se3, which results in two distinct conducting states denoted as "ON" and "OFF" with a large tunneling electroresistance (TER) ratio exceeding 105%. These findings suggest the importance of ferroelectric vdW heterostructures in the design of FTJs and propose a promising route for applying the 2D ferroelectric/semiconductor heterostructures with out-of-plane polarization in high-density ferroelectric memory devices.

17.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835283

RESUMO

G protein-coupled receptors (GPCRs) are the largest family of transmembrane receptors and play important roles in many physiological processes. As a representative group of protozoa, ciliates represent the highest stage of eukaryotic cell differentiation and evolution in terms of their reproductive mode, two-state karyotype, and extremely diverse cytogenesis patterns. GPCRs have been poorly reported in ciliates. In this study, we identified 492 GPCRs in 24 ciliates. Using the existing classification system for animals, GPCRs in ciliates can be assigned to four families, including families A, B, E, and F. Most (377 members) belong to family A. The number of GPCRs is extremely different in different ciliates; the Heterotrichea ciliates usually have more GPCRs than other ciliates. Parasitic or symbiotic ciliates usually have only a few GPCRs. Gene/genome duplication events seem to play important roles in the expansion of the GPCR superfamily in ciliates. GPCRs in ciliates displayed seven typical domain organizations. GPCRs in an ortholog group are common and conserved in all ciliates. The gene expression analysis of the members in this conserved ortholog group in the model ciliate, Tetrahymena thermophila, suggested that these GPCRs play important roles in the life cycle of ciliates. In summary, this study provides the first comprehensive genome-wide identification of GPCRs in ciliates, improving our understanding of the evolution and function of GPCR in ciliates.


Assuntos
Cilióforos , Evolução Molecular , Animais , Filogenia , Receptores Acoplados a Proteínas G/genética , Genoma , Cilióforos/genética
18.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445967

RESUMO

Balantioides coli plays an important role in the diarrhea of weaned piglets, but its pathogenic potential and interaction with gut microbes remain unclear. To investigate the impact of B. coli colonization on the gut bacterial structure and function of weaned piglets, a metagenomic analysis based on shotgun sequencing was performed on fresh fecal samples collected from ten B. coli-colonized piglets and eight B. coli-free ones in this study. The results showed that decreasing diversity and shifted composition and function of the bacterial community were detected in the weaned piglets infected by B. coli. In contrast to the B. coli-negative group, the relative abundances of some members of the Firmicutes phylum including Clostridium, Ruminococcus species, and Intestinimonas butyriciproducens, which produce short-chain fatty acids, were significantly reduced in the B. coli-positive group. Notably, some species of the Prevotella genus (such as Prevotella sp. CAG:604 and Prevotella stercorea) were significantly increased in abundance in the B. coli-positive piglets. A functional analysis of the gut microbiota demonstrated that the differential gene sets for the metabolism of carbohydrates and amino acids were abundant in both groups, and the more enriched pathways in B. coli-infected piglets were associated with the sugar-specific phosphotransferase system (PTS) and the two-component regulatory system, as well as lipopolysaccharide (LPS) biosynthesis. Furthermore, several species of Prevotella were significantly positively correlated to the synthesis of lipid A, leading to the exporting of endotoxins and, thereby, inducing inflammation in the intestines of weaned piglets. Taken together, these findings revealed that colonization by B. coli was distinctly associated with the dysbiosis of gut bacterial structure and function in weaned piglets. Lower relative abundances of Clostridiaceae and Ruminococcaceae and higher abundances of Prevotella species were biomarkers of B. coli infection in weaned piglets.


Assuntos
Balantidíase , Microbioma Gastrointestinal , Suínos , Animais , Microbioma Gastrointestinal/genética , Metagenoma , Virulência , Diarreia/microbiologia
19.
Int Braz J Urol ; 49(6): 716-731, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37624658

RESUMO

OBJECTIVES: Accurate preoperative prediction of adverse pathology is crucial for treatment planning of renal cell carcinoma (RCC). Previous studies have emphasized the potential of prostate-specific membrane antigen positron emission tomography / computed tomography (PSMA PET/CT) in differentiating between benign and malignant localized renal tumors. However, there is a scarcity of case reports elucidating the identification of aggressive pathological features using PET/CT. Our study was designed to prospectively compare the diagnostic value of enhanced CT, 68Ga-PSMA-11 and 18F-fluorodeoxyglucose (18F-FDG) PET/CT in clear-cell renal cell carcinoma (ccRCC) with necrosis or sarcomatoid or rhabdoid differentiation. MATERIALS AND METHODS: A prospective case series of patients with a newly diagnosed renal mass who underwent enhanced CT, 68Ga-PSMA-11 and 18F-FDG PET/CT within 30 days prior to nephrectomy was included. Complete preoperative and postoperative clinicopathological data were recorded. Patients who received neoadjuvant targeted therapy, declined enhanced CT or PET/CT scanning, refused surgical treatment or had non-ccRCC pathological indications were excluded. Radiological parameters were compared within subgroups of pathological characteristics. Bonferroni corrections were used to adjust for multiple testing and statistical significance was set at a p-value less than 0.017. RESULTS: Seventy-two patients were available for the final analysis. Enhanced CT demonstrated poor performance in identifying necrosis, sarcomatoid or rhabdoid differentiation and adverse pathology (all P > 0.05). The maximum standardized uptake value (SUVmax) of 68Ga-PSMA-11 PET/CT was more effective than 18F-FDG PET/CT in identifying tumor necrosis and adverse pathology, with an area under the curve (AUC) of 0.85 (cutoff value=25.26, p<0.001; Delong test z=2.709, p=0.007) for tumor necrosis and AUC of 0.90 (cutoff value=25.26, p<0.001; Delong test z=3.433, p<0.001) for adverse pathology. However, no significant statistical difference was found between 68Ga-PSMA-11 and 18F-FDG PET/CT in predicting sarcomatoid or rhabdoid feature (AUC of 0.91 vs.0.75, Delong test z=1.998, p=0.046). Subgroup analyses based on age, sex, tumor location, maximal diameter, stage and WHO/ISUP grade demonstrated that 68Ga-PSMA-11 PET/CT SUVmax had a significant predictive value for adverse pathology. Enhanced CT value and SUVmax demonstrated strong reliability [intraclass correlation coefficient (ICC) > 0.80], indicating a robust correlation. CONCLUSIONS: 68Ga-PSMA-11 PET/CT demonstrates distinct advantages in identifying aggressive pathological features of primary ccRCC when compared to enhanced CT and 18F-FDG PET/CT. Further research and assessment are warranted to fully establish the clinical utility of 68Ga-PSMA-11 PET/CT in ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Tomografia Computadorizada por Raios X , Necrose
20.
World J Microbiol Biotechnol ; 39(12): 325, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37776350

RESUMO

Lactococcus lactis (L. lactis) is the primary organism for lactic acid bacteria (LAB) and is a globally recognized safe microorganism for the regulation of the intestinal micro-ecological balance of animals and improving the immune performance of the host. L. lactis is known to play a commercially important role in feed fortification, milk fermentation, and vaccine production, but pathogenic L. lactis has been isolated from many clinical cases in recent years, such as the brain of silver carp with Lactococcosis, the liver and spleen of diseased waterfowl, milk samples and padding materials with cow mastitis, and blood and urine from human patients with endocarditis. In dairy farming, where L. lactis has been used as a probiotic in the past, however, some studies have found that L. lactis can cause mastitis in cows, but the lack of understanding of the pathogenesis of mastitis in cows caused by L. lactis has become a new problem. The main objective of this review is to analyze the increasingly serious clinical mastitis caused by L. lactis and combined with the wide application of L. lactis as probiotics, to comprehensively discuss the characteristics and diversity of L. lactis.


Assuntos
Lactococcus lactis , Mastite , Probióticos , Feminino , Humanos , Bovinos , Animais , Virulência , Leite/microbiologia
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