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1.
Cell ; 184(12): 3109-3124.e22, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34004145

RESUMO

Glycans modify lipids and proteins to mediate inter- and intramolecular interactions across all domains of life. RNA is not thought to be a major target of glycosylation. Here, we challenge this view with evidence that mammals use RNA as a third scaffold for glycosylation. Using a battery of chemical and biochemical approaches, we found that conserved small noncoding RNAs bear sialylated glycans. These "glycoRNAs" were present in multiple cell types and mammalian species, in cultured cells, and in vivo. GlycoRNA assembly depends on canonical N-glycan biosynthetic machinery and results in structures enriched in sialic acid and fucose. Analysis of living cells revealed that the majority of glycoRNAs were present on the cell surface and can interact with anti-dsRNA antibodies and members of the Siglec receptor family. Collectively, these findings suggest the existence of a direct interface between RNA biology and glycobiology, and an expanded role for RNA in extracellular biology.


Assuntos
Membrana Celular/metabolismo , Polissacarídeos/metabolismo , RNA/metabolismo , Animais , Anticorpos/metabolismo , Sequência de Bases , Vias Biossintéticas , Linhagem Celular , Sobrevivência Celular , Humanos , Espectrometria de Massas , Ácido N-Acetilneuramínico/metabolismo , Poliadenilação , Polissacarídeos/química , RNA/química , RNA/genética , RNA não Traduzido/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Coloração e Rotulagem
2.
Cell ; 182(2): 497-514.e22, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32579974

RESUMO

To define the cellular composition and architecture of cutaneous squamous cell carcinoma (cSCC), we combined single-cell RNA sequencing with spatial transcriptomics and multiplexed ion beam imaging from a series of human cSCCs and matched normal skin. cSCC exhibited four tumor subpopulations, three recapitulating normal epidermal states, and a tumor-specific keratinocyte (TSK) population unique to cancer, which localized to a fibrovascular niche. Integration of single-cell and spatial data mapped ligand-receptor networks to specific cell types, revealing TSK cells as a hub for intercellular communication. Multiple features of potential immunosuppression were observed, including T regulatory cell (Treg) co-localization with CD8 T cells in compartmentalized tumor stroma. Finally, single-cell characterization of human tumor xenografts and in vivo CRISPR screens identified essential roles for specific tumor subpopulation-enriched gene networks in tumorigenesis. These data define cSCC tumor and stromal cell subpopulations, the spatial niches where they interact, and the communicating gene networks that they engage in cancer.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Genômica/métodos , Neoplasias Cutâneas/metabolismo , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , RNA-Seq , Análise de Célula Única , Pele/metabolismo , Neoplasias Cutâneas/patologia , Transcriptoma , Transplante Heterólogo
3.
Cell ; 166(2): 451-467, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27419872

RESUMO

Stem-cell differentiation to desired lineages requires navigating alternating developmental paths that often lead to unwanted cell types. Hence, comprehensive developmental roadmaps are crucial to channel stem-cell differentiation toward desired fates. To this end, here, we map bifurcating lineage choices leading from pluripotency to 12 human mesodermal lineages, including bone, muscle, and heart. We defined the extrinsic signals controlling each binary lineage decision, enabling us to logically block differentiation toward unwanted fates and rapidly steer pluripotent stem cells toward 80%-99% pure human mesodermal lineages at most branchpoints. This strategy enabled the generation of human bone and heart progenitors that could engraft in respective in vivo models. Mapping stepwise chromatin and single-cell gene expression changes in mesoderm development uncovered somite segmentation, a previously unobservable human embryonic event transiently marked by HOPX expression. Collectively, this roadmap enables navigation of mesodermal development to produce transplantable human tissue progenitors and uncover developmental processes. VIDEO ABSTRACT.


Assuntos
Mesoderma/citologia , Transdução de Sinais , Proteínas Morfogenéticas Ósseas/metabolismo , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Coração/crescimento & desenvolvimento , Proteínas de Homeodomínio/metabolismo , Humanos , Mesoderma/metabolismo , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes/metabolismo , Linha Primitiva/citologia , Linha Primitiva/metabolismo , Análise de Célula Única , Somitos/metabolismo , Células-Tronco , Proteínas Supressoras de Tumor/metabolismo , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/metabolismo
4.
Nat Immunol ; 19(1): 76-84, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29180808

RESUMO

Exciting progress in the field of cancer immunotherapy has renewed the urgency of the need for basic studies of immunoregulation in both adaptive cell lineages and innate cell lineages. Here we found a central role for major histocompatibility complex (MHC) class I in controlling the phagocytic function of macrophages. Our results demonstrated that expression of the common MHC class I component ß2-microglobulin (ß2M) by cancer cells directly protected them from phagocytosis. We further showed that this protection was mediated by the inhibitory receptor LILRB1, whose expression was upregulated on the surface of macrophages, including tumor-associated macrophages. Disruption of either MHC class I or LILRB1 potentiated phagocytosis of tumor cells both in vitro and in vivo, which defines the MHC class I-LILRB1 signaling axis as an important regulator of the effector function of innate immune cells, a potential biomarker for therapeutic response to agents directed against the signal-regulatory protein CD47 and a potential target of anti-cancer immunotherapy.


Assuntos
Antígenos de Histocompatibilidade Classe I/imunologia , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/imunologia , Macrófagos/imunologia , Neoplasias/imunologia , Fagocitose/imunologia , Animais , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunoterapia/métodos , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Neoplasias/metabolismo , Neoplasias/terapia , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/terapia
6.
Nature ; 571(7764): 205-210, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31270459

RESUMO

The mammalian brain contains neurogenic niches that comprise neural stem cells and other cell types. Neurogenic niches become less functional with age, but how they change during ageing remains unclear. Here we perform single-cell RNA sequencing of young and old neurogenic niches in mice. The analysis of 14,685 single-cell transcriptomes reveals a decrease in activated neural stem cells, changes in endothelial cells and microglia, and an infiltration of T cells in old neurogenic niches. T cells in old brains are clonally expanded and are generally distinct from those in old blood, which suggests that they may experience specific antigens. T cells in old brains also express interferon-γ, and the subset of neural stem cells that has a high interferon response shows decreased proliferation in vivo. We find that T cells can inhibit the proliferation of neural stem cells in co-cultures and in vivo, in part by secreting interferon-γ. Our study reveals an interaction between T cells and neural stem cells in old brains, opening potential avenues through which to counteract age-related decline in brain function.


Assuntos
Envelhecimento/fisiologia , Encéfalo/citologia , Movimento Celular , Células-Tronco Neurais/citologia , Neurogênese , Análise de Célula Única , Nicho de Células-Tronco/fisiologia , Linfócitos T/citologia , Animais , Sangue , Proliferação de Células , Células Clonais/citologia , Técnicas de Cocultura , Células Endoteliais/citologia , Interferon gama/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Análise de Sequência de RNA , Transdução de Sinais , Linfócitos T/metabolismo , Transcriptoma/genética
7.
Inorg Chem ; 63(18): 8302-8311, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38652816

RESUMO

Diverse reactivity of the bulky tris(trimethylsilyl)silyl substituent [Si(SiMe3)3], also known as the hypersilyl group, was observed for amidinate-supported dichloro- and phenylchloroborane complexes. Treatment of the dichloroborane with potassium tris(trimethylsilyl)silyl led to the activation of the backbone ß-carbon center and formation of saturated four-membered heterocyclic chloroboranes R'{Si(SiMe3)3}C(NR)2BCl [R' = Ph, R = Cy (3); R' = Ph, R = iPr (6); R' = tBu, R = Cy (8)], whereas the four-membered amidinate hypersilyl-substituted phenyl borane 4 {PhC(NCy)2B(Ph)[Si(SiMe3)3]} was observed for the case of an amidinate-supported phenylchloroborane. The highly deshielded 11B NMR spectroscopic resonance and the distinct difference in the 29Si NMR spectrum confirmed the presence of a σ-donating hypersilyl effect on compounds 3, 6, and 8. Reaction of 3 with the Lewis acid AlCl3 led to the formation of complex 11 in which an unusual cleavage of one of the C-N bonds of the amidinate backbone is observed. Nucleophilic substitution at the boron center of saturated chloroborane 3 with phenyllithium generated the phenylborane derivative 12, whereas the secondary monomeric boron hydride 13 was observed after treatment with alane (AlH3). All compounds (2-13) have been fully characterized by NMR spectroscopy and single-crystal X-ray structure determination studies.

8.
Drug Dev Res ; 85(1): e22135, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37997034

RESUMO

The three-components one-pot Kabachnik-Fields reaction of sulfapyridine, diethyl phosphite, and aldehyde under thermal catalysis reaction condition in the presence of bismuth (III) triflate as a catalyst afford the corresponding sulfonamide-phosphonates (3a-3p) in good to excellent yields (78%-91%). The structures of the new synthesized compounds were elucidated and confirmed by variable spectroscopic studies. Single crystal X-ray studies for 3a, 3d, and 3i verified the proposed structure. The newly developed sulfonamide-phosphonates were evaluated for their inhibitory properties against four isoforms of human carbonic anhydrase (hCA I, II, IX, and XII). The results demonstrated that they exhibited greater potency in inhibiting hCA XII compared to hCA I, II, and IX, with Ki ranging from 5.1 to 51.1 nM. Compounds 3l and 3p displayed the highest potency, exhibiting selectivity ratios of I/XII >298.7 and 8.5, and II/XII ratios of 678.1 and 142.1, respectively. Molecular docking studies were conducted to explore their binding patterns within the binding pocket of CA XII. The results revealed that the sulfonamide NH group coordinated with the Zn2+ ion, and hydrogen bond interactions were observed with residue Thr200. Additionally, hydrophobic interactions were identified between the benzenesulfonamide phenyl ring and Leu198. Compounds 3p and 3l exhibited an additional hydrogen bonding interaction with other amino acid residues. These supplementary interactions may contribute to the enhanced potency and selectivity of these compounds toward the CA XII isoform.


Assuntos
Inibidores da Anidrase Carbônica , Anidrases Carbônicas , Humanos , Inibidores da Anidrase Carbônica/farmacologia , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Isoenzimas/metabolismo , Anidrases Carbônicas/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/química , Sulfanilamida , Estrutura Molecular
9.
Molecules ; 29(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474663

RESUMO

The controlled formation of mixed-metal bimetallics was realised through use of a fac-[Re(CO)3(N,N'-bpy-P)Cl] complex bearing an exogenous 2,4,6-trioxa-1,3,5,7-tetramethyl-8-phosphaadamantane donor at the 5-position of the bpy. The introduction of gold, silver, and rhodium with appropriate secondary ligands was readily achieved from established starting materials. Restricted rotation about the C(bpy)-P bond was observed in several of the bimetallic complexes and correlated with the relative steric bulk of the second metal moiety. Related chemistry with the 6-substituted derivative proved more limited in scope with only the bimetallic Re/Au complex being isolated.

10.
Cells Tissues Organs ; 212(2): 125-137, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34695818

RESUMO

The ephrin-B family of membrane-bound ligands is involved in skeletal patterning, osteogenesis, and bone homeostasis. Yet, despite the increasing collection of data affirming their importance in bone, the Eph tyrosine kinases that serve as the receptors for these ephrins in osteoblast stem cell niches remain unidentified. Here we report the expression of EphB3 at sites of bone growth in the embryo, especially at the calvaria suture fronts, periosteum, chondrocytes, and trabeculae of developing long bones. Strong EphB3 expression persisted in the adult calvarial sutures and in the proliferative chondrocytes of long bones, both of which are documented niches for osteoblastic stem cells. We observed EphB3-positive cells in the tissue filling a created calvarial injury, further implying EphB3 involvement in bone healing. Genetic knockout of EphB3 caused an increase in the bone tissue volume as a fraction of total volume in 6-week-old calvaria and in femoral trabecular density, compared to wild type controls. This difference resolved by 12 weeks of age, when we instead observed an increase in the bone volume of femoral trabeculae and in trabecular thickness. Our data identify EphB3 as a candidate regulator of osteogenesis either alone or in combination with other bone-expressed Ephs, and indicate that it appears to function as a limiter of bone growth.


Assuntos
Osteogênese , Receptores da Família Eph , Receptores da Família Eph/metabolismo , Efrinas/genética , Efrinas/metabolismo , Crânio , Osteoblastos
11.
Epidemiol Infect ; 151: e183, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37288508

RESUMO

Helminthiases cause significant health deficiencies among children. Mass administration of anthelminthic drugs has had significant results to counter these effects. We assessed the effects on and determinants of treatment coverage of community-directed treatment among children in Zambia, using cross-sectional survey data, and using chi-square test and multilevel mixed-effects model. Of 1,416 children, 51.5% were males and 48.5% were females, while 52.7%, were school-age, and 47.3% were preschool-age. Overall treatment coverage was 53.7% (95% confidence interval (CI) 51.1, 56.4). More preschool-age children were treated compared to school-age ones, 65.2% versus 43.4%, P < 0.001. Similarly, more children under community-directed intervention were treated compared to regular mass drug administration (65.2% versus 51.1 %, P < 0.001). Treatment among school-age participants was associated with being male (Adjusted Odds Ratio (AOR 1.83, 95%CI 1.23-2.72), receiving community-directed treatment (AOR 5.53; 95%CI 3.41-8.97), and shorter distance to health facility (AOR 2.20; 95%CI 1.36-3.56). Among preschool-aged participants, treatment was associated with being residents of Siavonga district (AOR 0.03; 95%CI 0.01-0.04) and shorter distance to health facility (AOR 0.35; 95%CI 0.21-0.59). Community-directed treatment can be used to increase treatment coverage, thereby contribute to 2030 vision of ending epidemics of neglected tropical diseases.


Assuntos
Helmintíase , Administração Massiva de Medicamentos , Criança , Feminino , Humanos , Masculino , Pré-Escolar , Pessoa de Meia-Idade , Estudos Transversais , Zâmbia , Helmintíase/tratamento farmacológico , Helmintíase/epidemiologia , Solo , Prevalência , Instalações de Saúde
12.
Nature ; 545(7655): 495-499, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28514441

RESUMO

Programmed cell death protein 1 (PD-1) is an immune checkpoint receptor that is upregulated on activated T cells for the induction of immune tolerance. Tumour cells frequently overexpress the ligand for PD-1, programmed cell death ligand 1 (PD-L1), facilitating their escape from the immune system. Monoclonal antibodies that block the interaction between PD-1 and PD-L1, by binding to either the ligand or receptor, have shown notable clinical efficacy in patients with a variety of cancers, including melanoma, colorectal cancer, non-small-cell lung cancer and Hodgkin's lymphoma. Although it is well established that PD-1-PD-L1 blockade activates T cells, little is known about the role that this pathway may have in tumour-associated macrophages (TAMs). Here we show that both mouse and human TAMs express PD-1. TAM PD-1 expression increases over time in mouse models of cancer and with increasing disease stage in primary human cancers. TAM PD-1 expression correlates negatively with phagocytic potency against tumour cells, and blockade of PD-1-PD-L1 in vivo increases macrophage phagocytosis, reduces tumour growth and lengthens the survival of mice in mouse models of cancer in a macrophage-dependent fashion. This suggests that PD-1-PD-L1 therapies may also function through a direct effect on macrophages, with substantial implications for the treatment of cancer with these agents.


Assuntos
Neoplasias do Colo/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Fagocitose , Receptor de Morte Celular Programada 1/metabolismo , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estadiamento de Neoplasias , Fagocitose/efeitos dos fármacos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Molecules ; 28(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37959672

RESUMO

The strategic planning of this study is based upon using the nanoformulation method to prepare nanoparticles 4-SLNs and 4-LPHNPs of the previously prepared 4,5-diphenyl-1H-pyrazolo[3,4-c]pyridazin-3-amine (4) after confirming its structure with single crystal X-ray analysis. These nanoparticles exhibited promising cytotoxic activity against HepG-2, HCT-116 and MCF-7 cancer cell lines in comparison with the reference doxorubicin and the original derivative 4. Moreover, their inhibitory assessment against EGFR and CDK-2/cyclin A2 displayed improved and more favorable impact than the parent 4 and the references. Detection of their influence upon cancer biomarkers revealed upregulation of Bax, p53 and caspase-3 levels and downregulation of Bcl-2 levels. The docking simulation demonstrated that the presence of the pyrazolo[3,4-c]pyridazin-3-amine scaffold is amenable to enclosure and binding well within EGFR and CDK-2 receptors through different hydrophilic interactions. The pharmacokinetic and physicochemical properties of target 4 were also assessed with ADME investigation, and the outcome indicated good drug-like characteristics.


Assuntos
Antineoplásicos , Nanopartículas , Piridazinas , Humanos , Relação Estrutura-Atividade , Proliferação de Células , Linhagem Celular Tumoral , Antineoplásicos/química , Receptores ErbB/metabolismo , Piridazinas/farmacologia , Aminas/farmacologia , Estrutura Molecular , Simulação de Acoplamento Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Proteínas Quinases/química
14.
Molecules ; 28(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37764378

RESUMO

The COVID-19 pandemic has posed a significant threat to society in recent times, endangering human health, life, and economic well-being. The disease quickly spreads due to the highly infectious SARS-CoV-2 virus, which has undergone numerous mutations. Despite intense research efforts by the scientific community since its emergence in 2019, no effective therapeutics have been discovered yet. While some repurposed drugs have been used to control the global outbreak and save lives, none have proven universally effective, particularly for severely infected patients. Although the spread of the disease is generally under control, anti-SARS-CoV-2 agents are still needed to combat current and future infections. This study reviews some of the most promising repurposed drugs containing indolyl heterocycle, which is an essential scaffold of many alkaloids with diverse bio-properties in various biological fields. The study also discusses natural and synthetic indole-containing compounds with anti-SARS-CoV-2 properties and computer-aided drug design (in silico studies) for optimizing anti-SARS-CoV-2 hits/leads.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Surtos de Doenças , Indóis/farmacologia , Indóis/uso terapêutico
15.
Am Heart J ; 251: 91-100, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35609671

RESUMO

BACKGROUND: Anxiety is a common comorbidity in patients with coronary heart disease (CHD) and is associated with worse prognosis. However, effective treatment for anxiety in CHD patients is uncertain. The UNWIND randomized clinical trial showed that 12-week treatment of escitalopram was better than exercise training or placebo in reducing anxiety in anxious CHD patients. The longer-term benefits of treatment for anxiety are not known. METHODS: Patients were randomized to 12 weeks of Escitalopram (up to 20 mg), Exercise (3 times/wk), or placebo pill. At the conclusion of treatment, participants were followed for 6-months to determine the persistence of benefit on the primary anxiety endpoint assessed by the Hospital Anxiety and Depression Scale-Anxiety scale (HADS-A) and to assess the effects of treatment on major adverse cardiac events over a follow-up period of up to 6 years. RESULTS: Of the 128 participants initially randomized, 120 (94%) were available for follow-up. Participants randomized to the Escitalopram condition exhibited lower HADS-A scores (3.9 [3.1, 4.7]) compared to those randomized to Exercise (5.5 [4.6, 6.3]) (P = .007) and Placebo (5.3 [4.1, 6.5]) (P = .053). Over a median follow-up of 3.2 years (IQR: 2.3, 4.5), there were 29 adverse events but no significant between-group differences. CONCLUSION: In the UNWIND trial, 12 weeks of escitalopram treatment was effective in reducing anxiety. These beneficial effects were sustained for 6 months posttreatment. Although moderate or vigorous physical activity has a number of health benefits, exercise was not an effective treatment for anxiety in patients with CHD.


Assuntos
Citalopram , Doença das Coronárias , Ansiedade/etiologia , Citalopram/uso terapêutico , Doença das Coronárias/complicações , Doença das Coronárias/tratamento farmacológico , Escitalopram , Exercício Físico , Seguimentos , Humanos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
16.
Bioorg Chem ; 119: 105557, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34952242

RESUMO

A new set of ibuprofen-quinoline conjugates comprising quinolinyl heterocycle and ibuprofen moieties linked by an alkyl chain were synthesized in good yields utilizing an optimized reaction procedure in a molecular hybridization approach to overcome the drawbacks of the current non-steroidal anti-inflammatory drugs. The synthesized conjugates were screened for their anti-inflammatory, and ulcerogenic properties. Several conjugates were found to have significant anti-inflammatory properties in the carrageenan-induced rat paw edema test without showing any ulcerogenic liability. In addition, most conjugates showed promising peripheral analgesic activity in the acetic acid-induced writhing test as well as central analgesic properties in the in vivo hot plate test. The most promising conjugates were the unsubstituted and 6-substituted fluoro- and chloro-derivatives of 2-(trifluoromethyl)quinoline linked to ibuprofen by a propyl chain. Their anti-inflammatory activity was evaluated against LPS-stimulated inflammatory reactions in RAW264.7 mouse macrophages. In this regard, it was found that most of the conjugates were able to significantly reduce the release and production of nitric oxide in the LPS-stimulated macrophages. The secretion and expression of the pro-inflammatory cytokines IL-6, TNF-α, and inducible nitric oxide synthase (iNOS) were also significantly suppressed.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Desenho de Fármacos , Ibuprofeno/farmacologia , Quinolinas/farmacologia , Ácido Acético , Analgésicos/síntese química , Analgésicos/química , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/síntese química , Inibidores de Ciclo-Oxigenase/química , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Relação Dose-Resposta a Droga , Ibuprofeno/química , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Dor/induzido quimicamente , Dor/tratamento farmacológico , Relação Quantitativa Estrutura-Atividade , Quinolinas/química , Células RAW 264.7
17.
Proc Natl Acad Sci U S A ; 116(50): 25115-25125, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31754028

RESUMO

Hematopoietic stem cells (HSCs) self-renew and generate all blood cells. Recent studies with single cell transplants and lineage tracing suggest that adult HSCs are diverse in their reconstitution and lineage potentials. However, prospective isolation of these subpopulations has remained challenging. Here, we identify Neogenin-1 (NEO1) as a unique surface marker on a fraction of mouse HSCs labeled with Hoxb5, a specific reporter of long-term HSCs (LT-HSCs). We show that NEO1+Hoxb5+ LT-HSCs expand with age and respond to myeloablative stress in young mice while NEO1-Hoxb5+ LT-HSCs exhibit no significant change in number. Furthermore, NEO1+Hoxb5+ LT-HSCs are more often in the G2/S cell cycle phase compared to NEO1-Hoxb5+ LT-HSCs in both young and old bone marrow. Upon serial transplantation, NEO1+Hoxb5+ LT-HSCs exhibit myeloid-biased differentiation and reduced reconstitution while NEO1-Hoxb5+ LT-HSCs are lineage-balanced and stably reconstitute recipients. Gene expression analysis reveals erythroid and myeloid priming in the NEO1+ fraction and association of quiescence and self-renewal-related transcription factors with NEO1- LT-HSCs. Finally, transplanted NEO1+Hoxb5+ LT-HSCs rarely generate NEO1-Hoxb5+ LT-HSCs while NEO1-Hoxb5+ LT-HSCs repopulate both LT-HSC fractions. This supports a model in which dormant, balanced NEO1-Hoxb5+ LT-HSCs can hierarchically precede active, myeloid-biased NEO1+Hoxb5+ LT-HSCs.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Proteínas de Homeodomínio/metabolismo , Proteínas de Membrana/metabolismo , Envelhecimento , Animais , Feminino , Transplante de Células-Tronco Hematopoéticas , Proteínas de Homeodomínio/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos
18.
Molecules ; 27(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408592

RESUMO

The title compound was synthesized and structurally characterized. Theoretical IR, NMR (with the GIAO technique), UV, and nonlinear optical properties (NLO) in four different solvents were calculated for the compound. The calculated HOMO-LUMO energies using time-dependent (TD) DFT revealed that charge transfer occurs within the molecule, and probable transitions in the four solvents were identified. The in silico absorption, distribution, metabolism, and excretion (ADME) analysis was performed in order to determine some physicochemical, lipophilicity, water solubility, pharmacokinetics, drug-likeness, and medicinal properties of the molecule. Finally, molecular docking calculation was performed, and the results were evaluated in detail.


Assuntos
Análise Espectral Raman , Vibração , Hidrazinas , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Teoria Quântica , Solventes/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Triazóis
19.
Molecules ; 27(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36558037

RESUMO

Reactions of 1-(5-methyl)-1H-1,2,3-triazol-4-yl)ethan-1-ones and benzaldehydes in ethanol under basic conditions gave the corresponding chalcones. Reactions of the chalcones combined with thiosemicarbazide in dry ethanol containing sodium hydroxide afforded the corresponding pyrazolin-N-thioamides. Reactions of the synthesized pyrazolin-N-thioamides and several ketones (namely, ethyl 2-chloro-3-oxobutanoate, 2-bromoacetylbenzofuran, and hydrazonoyl chloride) gave the corresponding novel 2-(1,2,3-triazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazoles in high yields (77-90%). Additionally, 2-(4,5-dihydro-1H-pyrazol-1-yl)-4-(1H-1,2,3-triazol-4-yl)thiazoles were obtained in high yields (84-87%) from reactions with N-pyrazoline-thioamides and 4-bromoacetyl-1,2,3-triazoles under basic conditions. The structures of six of the newly synthesized heterocycles were confirmed by X-ray crystallography.


Assuntos
Chalconas , Tiazóis , Tiazóis/química , Etanol
20.
Int J Environ Sci Technol (Tehran) ; 19(2): 1057-1070, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34345237

RESUMO

A study of aerosol dispersion was conducted in a university classroom using a CO2 tracer gas emitted from three source locations in a steady release, one source location per test. The tracer gas emitted from the single source location represented the potentially infectious aerosol droplets emitted from a single student and was thus a way to examine the influence of one sick student on the rest of the class. Two parameters were adjusted during the testing-the spacing of the desks, which included a spread and compressed configuration, and the inclusion of three-sided clear dividers attached to the student desk surfaces. Tracer dispersion was measured through the use of monitors in 13 locations within the classroom, with eight monitors representing seated student locations, four monitors representing a standing instructor along the classroom front, and one monitor at the return vent in the ceiling. As expected, spacing strongly influenced concentration levels at desks adjacent to the source location. The use of dividers reduced overall student and instructor location tracer concentrations when compared to desks without dividers in most cases. Finally, the influence of air change differences on the results was noted with consistent trends. The experimental construct provides a systematic means for classroom testing that may be broadly applicable to various configurations of classrooms beyond the one tested.

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