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1.
Nature ; 575(7784): 618-621, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31776491

RESUMO

All stellar-mass black holes have hitherto been identified by X-rays emitted from gas that is accreting onto the black hole from a companion star. These systems are all binaries with a black-hole mass that is less than 30 times that of the Sun1-4. Theory predicts, however, that X-ray-emitting systems form a minority of the total population of star-black-hole binaries5,6. When the black hole is not accreting gas, it can be found through radial-velocity measurements of the motion of the companion star. Here we report radial-velocity measurements taken over two years of the Galactic B-type star, LB-1. We find that the motion of the B star and an accompanying Hα emission line require the presence of a dark companion with a mass of [Formula: see text] solar masses, which can only be a black hole. The long orbital period of 78.9 days shows that this is a wide binary system. Gravitational-wave experiments have detected black holes of similar mass, but the formation of such massive ones in a high-metallicity environment would be extremely challenging within current stellar evolution theories.

2.
Proc Natl Acad Sci U S A ; 119(40): e2123030119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161902

RESUMO

Lorises are a group of globally threatened strepsirrhine primates that exhibit many unusual physiological and behavioral features, including a low metabolic rate, slow movement, and hibernation. Here, we assembled a chromosome-level genome sequence of the pygmy loris (Xanthonycticebus pygmaeus) and resequenced whole genomes from 50 pygmy lorises and 6 Bengal slow lorises (Nycticebus bengalensis). We found that many gene families involved in detoxification have been specifically expanded in the pygmy loris, including the GSTA gene family, with many newly derived copies functioning specifically in the liver. We detected many genes displaying evolutionary convergence between pygmy loris and koala, including PITRM1. Significant decreases in PITRM1 enzymatic activity in these two species may have contributed to their characteristic low rate of metabolism. We also detected many evolutionarily convergent genes and positively selected genes in the pygmy loris that are involved in muscle development. Functional assays demonstrated the decreased ability of one positively selected gene, MYOF, to up-regulate the fast-type muscle fiber, consistent with the lower proportion of fast-twitch muscle fibers in the pygmy loris. The protein product of another positively selected gene in the pygmy loris, PER2, exhibited weaker binding to the key circadian core protein CRY, a finding that may be related to this species' unusual circadian rhythm. Finally, population genomics analysis revealed that these two extant loris species, which coexist in the same habitat, have exhibited an inverse relationship in terms of their demography over the past 1 million years, implying strong interspecies competition after speciation.


Assuntos
Adaptação Biológica , Evolução Biológica , Lorisidae , Adaptação Biológica/genética , Animais , Demografia , Hibernação , Lorisidae/genética , Metagenômica , Metaloendopeptidases/genética
3.
J Neurochem ; 168(6): 1080-1096, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38317263

RESUMO

Sevoflurane, the predominant pediatric anesthetic, has been linked to neurotoxicity in young mice, although the underlying mechanisms remain unclear. This study focuses on investigating the impact of neonatal sevoflurane exposure on cell-type-specific alterations in the prefrontal cortex (PFC) of young mice. Neonatal mice were subjected to either control treatment (60% oxygen balanced with nitrogen) or sevoflurane anesthesia (3% sevoflurane in 60% oxygen balanced with nitrogen) for 2 hours on postnatal days (PNDs) 6, 8, and 10. Behavioral tests and single-nucleus RNA sequencing (snRNA-seq) of the PFC were conducted from PNDs 31 to 37. Mechanistic exploration included clustering analysis, identification of differentially expressed genes (DEGs), enrichment analyses, single-cell trajectory analysis, and genome-wide association studies (GWAS). Sevoflurane anesthesia resulted in sociability and cognition impairments in mice. Novel specific marker genes identified 8 distinct cell types in the PFC. Most DEGs between the control and sevoflurane groups were unique to specific cell types. Re-defining 15 glutamatergic neuron subclusters based on layer identity revealed their altered expression profiles. Notably, sevoflurane disrupted the trajectory from oligodendrocyte precursor cells (OPCs) to oligodendrocytes (OLs). Validation of disease-relevant candidate genes across the main cell types demonstrated their association with social dysfunction and working memory impairment. Behavioral results and snRNA-seq collectively elucidated the cellular atlas in the PFC of young male mice, providing a foundation for further mechanistic studies on developmental neurotoxicity induced by anesthesia.


Assuntos
Anestésicos Inalatórios , Córtex Pré-Frontal , Sevoflurano , Animais , Sevoflurano/toxicidade , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Camundongos , Anestésicos Inalatórios/toxicidade , Masculino , Animais Recém-Nascidos , Feminino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estudo de Associação Genômica Ampla
4.
Mol Biol Evol ; 40(8)2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37494289

RESUMO

Although the continual expansion of the brain during primate evolution accounts for our enhanced cognitive capabilities, the drivers of brain evolution have scarcely been explored in these ancestral nodes. Here, we performed large-scale comparative genomic, transcriptomic, and epigenomic analyses to investigate the evolutionary alterations acquired by brain genes and provide comprehensive listings of innovatory genetic elements along the evolutionary path from ancestral primates to human. The regulatory sequences associated with brain-expressed genes experienced rapid change, particularly in the ancestor of the Simiiformes. Extensive comparisons of single-cell and bulk transcriptomic data between primate and nonprimate brains revealed that these regulatory sequences may drive the high expression of certain genes in primate brains. Employing in utero electroporation into mouse embryonic cortex, we show that the primate-specific brain-biased gene BMP7 was recruited, probably in the ancestor of the Simiiformes, to regulate neuronal proliferation in the primate ventricular zone. Our study provides a comprehensive listing of genes and regulatory changes along the brain evolution lineage of ancestral primates leading to human. These data should be invaluable for future functional studies that will deepen our understanding not only of the genetic basis of human brain evolution but also of inherited disease.


Assuntos
Encéfalo , Primatas , Camundongos , Humanos , Animais , Primatas/genética , Encéfalo/metabolismo , Evolução Molecular
5.
Mol Biol Evol ; 40(5)2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37134013

RESUMO

HIV-1 is a highly host-specific retrovirus that infects humans but not most nonhuman primates. Thus, the lack of a suitable primate model that can be directly infected with HIV-1 hinders HIV-1/AIDS research. In the previous study, we have found that the northern pig-tailed macaques (NPMs) are susceptible to HIV-1 infection but show a nonpathogenic state. In this study, to understand this macaque-HIV-1 interaction, we assembled a de novo genome and longitudinal transcriptome for this species during the course of HIV-1 infection. Using comparative genomic analysis, a positively selected gene, Toll-like receptor 8, was identified with a weak ability to induce an inflammatory response in this macaque. In addition, an interferon-stimulated gene, interferon alpha inducible protein 27, was upregulated in acute HIV-1 infection and acquired an enhanced ability to inhibit HIV-1 replication compared with its human ortholog. These findings coincide with the observation of persistently downregulated immune activation and low viral replication and can partially explain the AIDS-free state in this macaque following HIV-1 infection. This study identified a number of unexplored host genes that may hamper HIV-1 replication and pathogenicity in NPMs and provided new insights into the host defense mechanisms in cross-species infection of HIV-1. This work will facilitate the adoption of NPM as a feasible animal model for HIV-1/AIDS research.


Assuntos
Infecções por HIV , HIV-1 , Vírus da Imunodeficiência Símia , Animais , Humanos , Macaca nemestrina , HIV-1/genética , Genômica , Vírus da Imunodeficiência Símia/genética
6.
Langmuir ; 40(18): 9717-9724, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712354

RESUMO

Connectivity isomerization of the same aromatic molecular core with different substitution positions profoundly affects electron transport pathways and single-molecule conductance. Herein, we designed and synthesized all connectivity isomers of a thiophene (TP) aromatic ring substituted by two dihydrobenzo[b]thiophene (BT) groups with ethynyl spacers (m,n-TP-BT, (m,n = 2,3; 2,4; 2,5; 3,4)), to systematically probe how connectivity contributes to single-molecule conductance. Single-molecule conductance measurements using a scanning tunneling microscopy break junction (STM-BJ) technique show ∼12-fold change in conductance values, which follow an order of 10-4.83 G0 (2,4-TP-BT) < 10-4.78 G0 (3,4-TP-BT) < 10-4.06 G0 (2,3-TP-BT) < 10-3.75 G0 (2,5-TP-BT). Electronic structure analysis and theoretical simulations show that the connectivity isomerization significantly changes electron delocalization and HOMO-LUMO energy gaps. Moreover, the connectivity-dependent molecular structures lead to different quantum interference (QI) effects in electron transport, e.g., a strong destructive QI near E = EF leads the smallest conductance value for 2,4-TP-BT. This work proves a clear relationship between the connectivity isomerization and single-molecule conductance of thiophene heterocyclic molecular junctions for the future design of molecular devices.

7.
BMC Cardiovasc Disord ; 24(1): 120, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383323

RESUMO

BACKGROUND: Acute aortic syndrome (AAS) is a life-threatening condition. Inflammation plays a key role in the pathogenesis, development and progression of AAS, and is associated with significant mortality and morbidity. Understanding the inflammatory responses and inflammation resolutions is essential for an appropriate management of AAS. METHOD: Thirty Chinese cardiovascular centers have collaborated to create a multicenter observational registry (named Chinese Additive Anti-inflammatory Action for Aortopathy & Arteriopathy [5A] registry), with consecutive enrollment of adult patients who underwent surgery for AAS that was started on Jan 1, 2016 and will be ended on December 31, 2040. Specially, the impact of inflammation and anti-inflammatory strategies on the early and late adverse events are investigated. Primary outcomes are severe systemic inflammatory response syndrome (SIRS), multiple organ dysfunction syndrome (MODS), Sequential Organ Failure Assessment (SOFA) scores at 7 days following this current surgery. Secondary outcomes are SISR, 30-day mortality, operative mortality, hospital mortality, new-onset stroke, acute kidney injury, surgical site infection, reoperation for bleeding, blood transfusion and length of stay in the intensive care unit. DISCUSSION: The analysis of this multicenter registry will allow our better knowledge of the prognostic importance of preoperative inflammation and different anti-inflammatory strategies in adverse events after surgery for AAS. This registry is expected to provide insights into novel different inflammatory resolutions in management of AAS beyond conventional surgical repair. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04398992 (Initial Release: 05/19/2020).


Assuntos
Unidades de Terapia Intensiva , Doenças Vasculares , Adulto , Humanos , Anti-Inflamatórios , China , Inflamação , Estudos Multicêntricos como Assunto , Sistema de Registros , Estudos Observacionais como Assunto
8.
Nucleic Acids Res ; 50(18): 10249-10263, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36130267

RESUMO

Switching of G-quadruplex (G4) structures between variant types of folding has been proved to be a versatile tool for regulation of genomic expression and development of nucleic acid-based constructs. Various specific ligands have been developed to target G4s in K+ solution with therapeutic prospects. Although G4 structures have been reported to be converted by sequence modification or a unimolecular ligand binding event in K+-deficient conditions, switching G4s towards non-G4 folding continues to be a great challenge due to the stability of G4 in physiological K+ conditions. Herein, we first observed the G4 switching towards parallel-stranded duplex (psDNA) by multimolecular ligand binding (namely ligand clustering) to overcome the switching barrier in K+. Purine-rich sequences (e.g. those from the KRAS promoter region) can be converted from G4 structures to dimeric psDNAs using molecular rotors (e.g. thioflavin T and thiazole orange) as initiators. The formed psDNAs provided multiple binding sites for molecular rotor clustering to favor subsequent structures with stability higher than the corresponding G4 folding. Our finding provides a clue to designing ligands with the competency of molecular rotor clustering to implement an efficient G4 switching.


Assuntos
Quadruplex G , Ácidos Nucleicos , Análise por Conglomerados , Ligantes , Proteínas Proto-Oncogênicas p21(ras) , Purinas
9.
Chem Biodivers ; 21(6): e202400511, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38538539

RESUMO

Two undescribed germacrane-type sesquiterpenoids, salcasins A (1) and B (2), together with three known compounds (3-5) were isolated and identified from the whole plant of Salvia cavaleriei var. simplicifolia Stib. The structures of the undescribed compounds were elucidated on the basis of spectroscopic methods, such as HR-ESI-MS, 1D and 2D NMR data. The relative configurations of 1 and 2 were established by analyzing their NOESY spectra as well as by 13C NMR calculations with DP4+ probability analyses. The absolute configurations of 1 and 2 were determined by comparing experimental and calculated ECD spectra. Furthermore, the in vivo anti-Alzheimer's disease activities of 1-5 were evaluated using Caenorhabditis elegans AD pathological model. Among all isolated compounds, salcasin A (1) significantly delayed AD-like symptoms of worm paralysis, which may be a potential anti-AD candidate agent.


Assuntos
Doença de Alzheimer , Caenorhabditis elegans , Salvia , Sesquiterpenos de Germacrano , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Salvia/química , Caenorhabditis elegans/efeitos dos fármacos , Sesquiterpenos de Germacrano/farmacologia , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/isolamento & purificação , Estrutura Molecular , Conformação Molecular , Modelos Animais de Doenças
10.
Nano Lett ; 23(14): 6567-6573, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37410961

RESUMO

Owing to their unique and sustainable surface plasmonic properties, Al nanocrystals have attracted increasing attention for plasmonic-enhanced applications, including single-particle surface-enhanced Raman scattering (SERS). However, whether Al nanocrystals can achieve single-particle SERS is still unknown, mainly due to the synthetic difficulty of Al nanocrystals with internal gaps. Herein, we report a regrowth method for the synthesis of Al nanohexapods with tunable and uniform internal gaps for single-particle SERS with an enhancement factor of up to 1.79 × 108. The uniform branches of the Al nanohexapods can be systematically tuned regarding their dimensions, terminated facets, and internal gaps. The Al nanohexapods generate hot spots concentrated in the internal gaps due to the strong plasmonic coupling between the branches. A single-particle SERS measurement of Al nanohexapods shows strong Raman signals with maximum enhancement factors comparable to that of Au counterparts. The large enhancement factor indicates that Al nanohexapods are good candidates for single-particle SERS.

11.
Mol Biol Evol ; 39(3)2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35038730

RESUMO

The spotted hyena (Crocuta crocuta) is a large and unique terrestrial carnivore. It is a particularly fascinating species due to its distinct phenotypic traits, especially its complex social structure and scavenging lifestyle, with associated high dietary exposure to microbial pathogens. However, the underlying molecular mechanisms related to these phenotypes remain elusive. Here, we sequenced and assembled a high-quality long-read genome of the spotted hyena, with a contig N50 length of ∼13.75 Mb. Based on comparative genomics, immunoglobulin family members (e.g., IGKV4-1) showed significant adaptive duplications in the spotted hyena and striped hyena. Furthermore, immune-related genes (e.g., CD8A, LAG3, and TLR3) experienced species-specific positive selection in the spotted hyena lineage. These results suggest that immune tolerance between the spotted hyena and closely related striped hyena has undergone adaptive divergence to cope with prolonged dietary exposure to microbial pathogens from scavenging. Furthermore, we provided the potential genetic insights underlying social complexity, hinting at social behavior and cognition. Specifically, the RECNE-associated genes (e.g., UGP2 and ACTR2) in the spotted hyena genome are involved in regulation of social communication. Taken together, our genomic analyses provide molecular insights into the scavenging lifestyle and societal complexity of spotted hyenas.


Assuntos
Hyaenidae , Animais , Sequência de Bases , Genoma , Hyaenidae/genética , Comportamento Social
12.
N Engl J Med ; 382(18): 1708-1720, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32109013

RESUMO

BACKGROUND: Since December 2019, when coronavirus disease 2019 (Covid-19) emerged in Wuhan city and rapidly spread throughout China, data have been needed on the clinical characteristics of the affected patients. METHODS: We extracted data regarding 1099 patients with laboratory-confirmed Covid-19 from 552 hospitals in 30 provinces, autonomous regions, and municipalities in mainland China through January 29, 2020. The primary composite end point was admission to an intensive care unit (ICU), the use of mechanical ventilation, or death. RESULTS: The median age of the patients was 47 years; 41.9% of the patients were female. The primary composite end point occurred in 67 patients (6.1%), including 5.0% who were admitted to the ICU, 2.3% who underwent invasive mechanical ventilation, and 1.4% who died. Only 1.9% of the patients had a history of direct contact with wildlife. Among nonresidents of Wuhan, 72.3% had contact with residents of Wuhan, including 31.3% who had visited the city. The most common symptoms were fever (43.8% on admission and 88.7% during hospitalization) and cough (67.8%). Diarrhea was uncommon (3.8%). The median incubation period was 4 days (interquartile range, 2 to 7). On admission, ground-glass opacity was the most common radiologic finding on chest computed tomography (CT) (56.4%). No radiographic or CT abnormality was found in 157 of 877 patients (17.9%) with nonsevere disease and in 5 of 173 patients (2.9%) with severe disease. Lymphocytopenia was present in 83.2% of the patients on admission. CONCLUSIONS: During the first 2 months of the current outbreak, Covid-19 spread rapidly throughout China and caused varying degrees of illness. Patients often presented without fever, and many did not have abnormal radiologic findings. (Funded by the National Health Commission of China and others.).


Assuntos
Betacoronavirus , Infecções por Coronavirus , Surtos de Doenças , Pandemias , Pneumonia Viral , Adolescente , Adulto , Idoso , COVID-19 , Criança , China/epidemiologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Feminino , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , SARS-CoV-2 , Adulto Jovem
13.
Anal Chem ; 95(7): 3746-3753, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36745842

RESUMO

Abnormal amplification of trinucleotide repeats (TNRs) is associated with neurodegenerative diseases by forming a particular hairpin bulge. It is well known that the polarity and parity of TNRs can regulate the formed hairpin structures. Therefore, there is a great challenge to efficiently discriminate the hairpin structures of TNRs with substantial selectivity. Herein, we developed a fluorescent ligand of pseudohypericin (Pse) with a beyond-size-matching (BSM) geometry to selectively sense hairpin structures of GTC and CTG TNRs. The GTC hairpin structures can bind with Pse dominantly at extreme T-T mismatches by the virtue of their most extrahelical conformations, while there is no binding event to occur with the polarity-inverted counterpart CTG hairpin structures because of the limited space provided by their intrahelical T-T mismatches. In addition, this all-or-none response with the polarity-dependent folding (PoDF) is independent of the length of these TNRs. Interestingly, the parity-dependent folding (PaDF) of GTC hairpin structures can also be resolved. Besides pure TNRs, the competency of this BSM ligand to sense the PoDF and PaDF effects was also generalized to DNAs with TNRs occurring at loop and stem end regions. To our knowledge, this is the first experimental observation with the state-of-the-art performance over the fluorescence measurement of PoDF and PaDF in TNRs. Our work provides an expedient way to elucidate the TNR folding by designing ligands having BSM features.


Assuntos
Doenças Neurodegenerativas , Repetições de Trinucleotídeos , DNA/química , Ligantes , Conformação de Ácido Nucleico , Expansão das Repetições de Trinucleotídeos
14.
Anal Chem ; 95(41): 15367-15374, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37784221

RESUMO

Triplex DNA structures have displayed a wide range of applications including nanosensing, molecule switching, and drug delivering. Therefore, it is of great importance to effectively recognize triplex DNA structures by a simple and highly selective manner. Herein, we found that a near-infrared fluorogenic probe of NIAD-4 with a molecular rotor (MR) merit can selectively recognize triplex DNA structures over G-quadruplex, i-motif, and duplex structures (Tri-over-QID selectivity), which is competent over the widely used MR probe of thioflavin T (ThT). Furthermore, NIAD-4 exhibits as well a high selectivity toward the 'pyrimidine-type' triplex structures (Y:R-Y type) with respect to the 'purine-type' triplex structures (R:R-Y type) (a Y-over-R selectivity). Interestingly, NIAD-4 recognizes the Y:R-Y triplex structures by a polarity-dependent manner. The 3' end triplet is the preferential binding field of NIAD-4 with respect to the 5' end one (a 3'-over-5' selectivity) as the 3' end triplet is more stable than the 5' end one in the Hoogsteen hydrogen bond. It is expected that the adaptive stacking interaction between NIAD-4 and the 3' end triplet favors the Tri-over-QID, Y-over-R, and 3'-over-5' selectivities since this MR probe has three rotating shafts matching well with the triplet in topology. Such a high selectivity of NIAD-4 opens a new route in designing sensors with DNA structures switching between triplex, i-motif, and G-quadruplex structures.


Assuntos
DNA , Purinas , Conformação de Ácido Nucleico , DNA/química , Purinas/química , Pirimidinas
15.
Hematol Oncol ; 41(2): 248-256, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34472655

RESUMO

This retrospective cohort study aimed to evaluate primary treatment and recent survival trends in patients with primary diffuse large B-cell lymphoma of central nervous system (CNS) from 1995 to 2016. Using the SEER data, patients diagnosed with non-HIV-associated primary central nervous system lymphoma (PCNSL)-diffuse large B-cell lymphoma (DLBCL) aged ⩾18 years between 1995 and 2016 were identified. The year of diagnosis was divided into the time period-1 (1995-2002), the time period-2 (2003-2012), and the time period-3 (2013-2016). Chi-square tests, the Kaplan-Meier method, log-rank test, and Cox regression model were used in the analysis. Overall, 3760 patients were included. Both the use of radiotherapy alone and the application of combined chemoradiotherapy decreased significantly, following the wider use of chemotherapy alone during 1995-2016. There was a significant improvement in PCNSL cause-specific survival (CSS) (period-1: 13 months vs. period-2: 19 months vs. period-3: 41 months, p < 0.001). Survival of patients aged above 70 years did not change from the time period-1 to the time period-2 (p = 0.101). However, there was an increase in CSS from the time period-2 to the time period-3 in the elderly patients (period-2: 5 months vs. period-3: 9 months, p < 0.001). On multivariable analyses, diagnosed in the time period-3 was significantly and independently associated with better CSS (hazard ratio 0.577, 95% confidence interval 0.506-0.659, p < 0.001). Our analysis shows the use of radiotherapy in the treatment of PCNSL has waned over the study span. There was a significant improvement in CSS during 1995-2016, which reflected developments in treatment over time. The elderly patient population also gained a significant CSS benefit in the most recent period.


Assuntos
Neoplasias do Sistema Nervoso Central , Linfoma Difuso de Grandes Células B , Linfoma não Hodgkin , Idoso , Humanos , Estudos Retrospectivos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Sistema Nervoso Central/patologia
16.
Anesthesiology ; 138(5): 477-495, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36752736

RESUMO

BACKGROUND: Multiple neonatal exposures to sevoflurane induce neurocognitive dysfunctions in rodents. The lack of cell type-specific information after sevoflurane exposure limits the mechanistic understanding of these effects. In this study, the authors tested the hypothesis that sevoflurane exposures alter the atlas of hippocampal cell clusters and have neuronal and nonneuronal cell type-specific effects in mice of both sexes. METHODS: Neonatal mice were exposed to 3% sevoflurane for 2 h at postnatal days 6, 8, and 10 and analyzed for the exposure effects at postnatal day 37. Single-nucleus RNA sequencing was performed in the hippocampus followed by in situ hybridization to validate the results of RNA sequencing. The Morris Water Maze test was performed to test neurocognitive function. RESULTS: The authors found sex-specific distribution of hippocampal cell types in control mice alongside cell type- and sex-specific effects of sevoflurane exposure on distinct hippocampal cell populations. There were important changes in male but not in female mice after sevoflurane exposure regarding the proportions of cornu ammonis 1 neurons (control vs. sevoflurane, males: 79.9% vs. 32.3%; females: 27.3% vs. 24.3%), dentate gyrus (males: 4.2% vs. 23.4%; females: 36.2% vs. 35.8%), and oligodendrocytes (males: 0.6% vs. 6.9%; females: 5.9% vs. 7.8%). In male but not in female mice, sevoflurane altered the number of significantly enriched ligand-receptor pairs in the cornu ammonis 1, cornu ammonis 3, and dente gyrus trisynaptic circuit (control vs. sevoflurane, cornu ammonis 1-cornu ammonis 3: 18 vs. 42 in males and 15 vs. 21 in females; cornu ammonis 1-dentate gyrus: 21 vs. 35 in males and 12 vs. 20 in females; cornu ammonis 3-dentate gyrus: 25 vs. 45 in males and 17 vs. 20 in females), interfered with dentate gyrus granule cell neurogenesis, hampered microglia differentiation, and decreased cornu ammonis 1 pyramidal cell diversity. Oligodendrocyte differentiation was specifically altered in females with increased expressions of Mbp and Mag. In situ hybridization validated the increased expression of common differentially expressed genes. CONCLUSIONS: This single-nucleus RNA sequencing study reveals the hippocampal atlas of mice, providing a comprehensive resource for the neuronal and nonneuronal cell type- and sex-specific effects of sevoflurane during development.


Assuntos
Giro Denteado , Hipocampo , Masculino , Feminino , Animais , Camundongos , Sevoflurano/farmacologia , Giro Denteado/metabolismo , Neurônios , Células Piramidais
17.
J Org Chem ; 88(6): 3499-3508, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36891880

RESUMO

Rh(III)-catalyzed C-H/N-H annulation and C-H allylation of phenylindazolones have been realized by employing 5-methylene-1,3-dioxan-2-one and 4-vinyl-1,3-dioxolan-2-one as scalable cross-coupling partners, delivering functionalized indazolone fused heterocycles and branched and linear allyl indazolones respectively in moderate to high yield. These divergent synthesis protocols showcase mild conditions, broad substrate scope, and high functional-group compatibility. In addition, scale-up synthesis and preliminary mechanistic exploratory were also accomplished.

18.
J Org Chem ; 88(9): 5512-5519, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37011236

RESUMO

The indole-substituted trifluoromethyl sulfonium ylide has been developed via Cp*Rh(III)-catalyzed diazo-carbenoid addition to trifluoromethylthioether and is the first example of an Rh(III)-catalyzed diazo-carbenoid addition reaction with trifluoromethylthioether. Several kinds of indole-substituted trifluoromethyl sulfonium ylide were constructed under mild reaction conditions. The reported method exhibited high functional group compatibility and broad substrate scope. In addition, the protocol was found to be complementary to the method disclosed by a Rh(II) catalyst.

19.
Cardiology ; 148(5): 448-456, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37429265

RESUMO

INTRODUCTION: Knowledge is limited regarding the significance of pulmonary arterial pressure (PAP) in predominantly congenital mitral valve regurgitation (MR)-based intracardiac abnormalities. METHODS: From a prospective cohort, we included 200 patients with congenital MR regardless of other associated intracardiac abnormalities (mean age 60.4 months, 67% female, systolic PAP (sPAP) 54.2 mm Hg) surgically repaired in 2012-2019 and followed up to 2020 (median 30.0 months). Significant pulmonary hypertension (PH) was defined as sPAP >50 mm Hg at rest or mean PAP >25 mm Hg on right heart catheterization. By perioperative sPAP changes, patients were stratified as group I (pre-normotension to post-normotension), group II (pre-hypertension to post-normotension), or group III (pre-hypertension to post-hypertension). Primary outcomes were the recurrence of MR (defined as the regurgitation grade of moderate or greater) and the progression of MR (defined as any increase in the magnitude of regurgitation grade after surgery). Cox proportional hazard and Kaplan-Meier curve were performed. RESULTS: There was no association between preoperative PH and the recurrent MR (adjusted hazard ratios [aHR]: 1.146 [95% CI: 0.453-2.899]) and progressive MR (aHR: 1.753 [95% CI: 0.807-3.804]), respectively. There were no significant differences among group I, group II, and group III in the recurrent MR but in the progressive MR. A dose dependency was identified for preoperative sPAP with recurrent MR (aHR: 1.050 [95% CI: 1.029-1.071]) and progressive MR risks (aHR: 1.037 [95% CI: 1.019-1.055]), respectively. CONCLUSIONS: Preoperative higher sPAP is associated with worse outcomes, warranting heightened attention to the identification of perioperative sPAP.


Assuntos
Hipertensão Pulmonar , Insuficiência da Valva Mitral , Pré-Hipertensão , Humanos , Feminino , Pré-Escolar , Masculino , Prognóstico , Pressão Arterial , Estudos Prospectivos , Resultado do Tratamento , Pré-Hipertensão/complicações , Valva Mitral/cirurgia , Hipertensão Pulmonar/complicações , Estudos Retrospectivos
20.
J Nat Prod ; 86(2): 357-367, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36753718

RESUMO

Bioinformatics analysis of a whole genome sequence coupled with HPLC-DAD analysis revealed that Streptomyces sp. Hu103 has the capacity to produce skyllamycin analogues. A subsequent chemical investigation of this strain yielded four new cinnamoyl-containing cyclopeptides, anulamycins A-D (1-4), two new cinnamoyl-containing linear peptides, anulamycins E and F (5 and 6), and two known cyclopeptides, skyllamycins A (7) and B (8). Their structures including absolute configurations were elucidated by detailed analysis of NMR and HRESIMS/MS spectroscopic data and the advanced Marfey's method. Compounds 1-4 exhibited antibacterial activity comparable to those of skyllamycins A and B.


Assuntos
Streptomyces , Streptomyces/química , Lagos , Peptídeos Cíclicos/química , Espectroscopia de Ressonância Magnética , Antibacterianos/química , Estrutura Molecular
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