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1.
J Environ Sci (China) ; 147: 561-570, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003071

RESUMO

In the present study, we investigated the influence of surface fluorine (F) on TiO2 for the photocatalytic oxidation (PCO) of toluene. TiO2 modified with different F content was prepared and tested. It was found that with the increasing of F content, the toluene conversion rate first increased and then decreased. However, CO2 mineralization efficiency showed the opposite trend. Based on the characterizations, we revealed that F substitutes the surface hydroxyl of TiO2 to form the structure of Ti-F. The presence of the appropriate amount of surface Ti-F on TiO2 greatly enhanced the separation of photogenerated carriers, which facilitated the generation of ·OH and promoted the activity for the PCO of toluene. It was further revealed that the increase of only ·OH promoted the conversion of toluene to ring-containing intermediates, causing the accumulation of intermediates and then conversely inhibited the ·OH generation, which led to the decrease of the CO2 mineralization efficiency. The above results could provide guidance for the rational design of photocatalysts for toluene oxidation.


Assuntos
Fluoretos , Oxirredução , Titânio , Tolueno , Tolueno/química , Titânio/química , Catálise , Fluoretos/química , Processos Fotoquímicos , Modelos Químicos
2.
Cancer Cell ; 42(7): 1268-1285.e7, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981439

RESUMO

Expanding the efficacy of immune checkpoint blockade (ICB) in colorectal cancer (CRC) presses for a comprehensive understanding of treatment responsiveness. Here, we analyze multiple sequential single-cell samples from 22 patients undergoing PD-1 blockade to map the evolution of local and systemic immunity of CRC patients. In tumors, we identify coordinated cellular programs exhibiting distinct response associations. Specifically, exhausted T (Tex) or tumor-reactive-like CD8+ T (Ttr-like) cells are closely related to treatment efficacy, and Tex cells show correlated proportion changes with multiple other tumor-enriched cell types following PD-1 blockade. In addition, we reveal the less-exhausted phenotype of blood-associated Ttr-like cells in tumors and find that their higher abundance suggests better treatment outcomes. Finally, a higher major histocompatibility complex (MHC) II-related signature in circulating CD8+ T cells at baseline is linked to superior responses. Our study provides insights into the spatiotemporal cellular dynamics following neoadjuvant PD-1 blockade in CRC.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Colorretais , Imunoterapia , Análise de Célula Única , Humanos , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/terapia , Neoplasias Colorretais/patologia , Análise de Célula Única/métodos , Linfócitos T CD8-Positivos/imunologia , Imunoterapia/métodos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos do Interstício Tumoral/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Masculino , Feminino
3.
Am J Clin Pathol ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037433

RESUMO

OBJECTIVES: Widely accepted standardized criteria for peripheral blood (PB) smear review do not exist. The aim of this study was to collect data regarding PB smear review practices across multiple institutions, with a focus on pathologist review. METHODS: A 23-question survey was developed by members of the Society for Hematopathology (SH) Education Committee and distributed to SH members. The survey included questions on practice environment and PB smear review practices, including trainee involvement. RESULTS: Of 725 members contacted, 137 (19%) completed the entire survey. Over half of practices examined 5 to 20 smears a day. All respondents reported using complete blood count/differential leukocyte count data and clinical history as part of smear review. The reported proportion of laboratory-initiated vs clinician-requested reviews varied across respondents. Clinician-requested smear reviews were more likely to be billed and issued as a separate pathology report. Glass slide review (as opposed to digital microscopy) was used by most respondents. All respondents affirmed that PB smear review is an essential component of pathology training programs. Numerous free-text comments were submitted by respondents regarding their own experiences with PB smear review and suggested improvements. CONCLUSIONS: This survey elucidated the spectrum of practice patterns for pathologist review of blood smears and identified potential areas for process improvement.

4.
Cell ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39047727

RESUMO

Characterizing the compositional and phenotypic characteristics of tumor-infiltrating B cells (TIBs) is important for advancing our understanding of their role in cancer development. Here, we establish a comprehensive resource of human B cells by integrating single-cell RNA sequencing data of B cells from 649 patients across 19 major cancer types. We demonstrate substantial heterogeneity in their total abundance and subtype composition and observe immunoglobulin G (IgG)-skewness of antibody-secreting cell isotypes. Moreover, we identify stress-response memory B cells and tumor-associated atypical B cells (TAABs), two tumor-enriched subpopulations with prognostic potential, shared in a pan-cancer manner. In particular, TAABs, characterized by a high clonal expansion level and proliferative capacity as well as by close interactions with activated CD4 T cells in tumors, are predictive of immunotherapy response. Our integrative resource depicts distinct clinically relevant TIB subsets, laying a foundation for further exploration of functional commonality and diversity of B cells in cancer.

5.
Hum Pathol ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971327

RESUMO

The PICALM::MLLT10 fusion is a rare but recurrent cytogenetic abnormality in acute leukemia, with limited clinicopathologic and outcome data available. Herein, we analyzed 156 acute leukemia patients with PICALM::MLLT10 fusion, including 12 patients from our institutions and 144 patients from the literature. The PICALM::MLLT10 fusion preferentially manifested in pediatric and young adult patients, with a median age of 24 years. T-lymphoblastic leukemia/lymphoma (T-ALL) constituted 65% of cases, acute myeloid leukemia (AML) 27%, and acute leukemia of ambiguous lineage (ALAL) 8%. About half of T-ALL were classified as an early T-precursor (ETP)-ALL. In our institutions' cohort, mediastinum was the most common extramedullary site of involvement. Eight of 12 patients were diagnosed with T-ALL exhibiting a pro-/pre-T stage phenotype (CD4/CD8-double negative, CD7-positive), and frequent CD79a expression. NGS revealed pathogenic mutations in 5 of 6 tested cases, including NOTCH1, and genes in RAS and JAK-STAT pathways and epigenetic modifiers. Of 138 cases with follow-up, pediatric patients (<18 years) had 5-year overall survival (OS) of 71%, significantly better than adults at 33%. The 5-year OS for AML patients was 25%, notably shorter than T-ALL patients at 54%; this distinction was observed in both pediatric and adult populations. Furthermore, adult but not pediatric ETP-ALL patients demonstrated inferior survival compared to non-ETP-ALL patients. Neither karyotype complexity nor transplant status had a discernible impact on OS. In conclusion, PICALM::MLLT10 fusion is most commonly seen in T-ALL patients, particularly those with an ETP phenotype. AML and adult ETP-ALL patients had adverse prognosis. PICALM::MLTT10 fusion testing should be considered in T-ALL, AML, and ALAL patients.

6.
Plant Physiol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808472

RESUMO

Non-canonical peptides (NCPs) are a class of peptides generated from regions previously thought of as non-coding, such as introns, 5' untranslated regions (UTRs), 3' UTRs, and intergenic regions. In recent years, the significance and diverse functions of NCPs have come to light, yet a systematic and comprehensive NCP database remains absent. Here, we developed NCPbook (https://ncp.wiki/ncpbook/), a database of evidence-supported NCPs, which aims to provide a resource for efficient exploration, analysis, and manipulation of NCPs. NCPbook incorporates data from diverse public databases and scientific literature. The current version of NCPbook includes 180,676 NCPs across 29 different species, evidenced by mass spectrometry (MS), ribosome profiling (Ribo-seq), or molecular experiments (ME). These NCPs are distributed across kingdoms, comprising 123,408 from 14 plant species, 56,999 from seven animal species, and 269 from eight microbial species. Furthermore, NCPbook encompasses 9,166 functionally characterized NCPs playing important roles in immunity, stress resistance, growth, and development. Equipped with a user-friendly interface, NCPbook allows users to search, browse, visualize, and retrieve data, making it an indispensable platform for researching NCPs in various plant, animal, and microbial species.

7.
Water Res ; 258: 121822, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38796915

RESUMO

This study investigated the co-transport behaviors of nano zero-valent iron (nZVI) and Cd(II) in the presence of soil nanoparticles (SNPs) under various SNPs/nZVI mass ratios. It was illustrated that the mobility of colloidal Cd(II) was highly dependent on the nZVI-SNPs heteroaggregation behavior. In the case of 40 mg/L nZVI with SNPs/nZVI mass ratios > 1, the formation of stable SNPs-nZVI heteroaggregates with hydrodynamic diameters (Dh) < 500 nm facilitated the nZVI and colloidal Cd(II) transport at their effluent mass recoveries of 34.76-37.82 % and 9.81-17.17 %, respectively. However, in the case of 100 mg/L nZVI with SNPs/nZVI mass ratios of 0.4-2, the interception of nZVI-SNPs heteroaggregates with Dh > 1500 nm by quartz sands led to almost complete retention of nZVI and colloidal Cd(II) in the columns. Combined with analytical results of zeta potentials and XRD spectrum, it was revealed that the Cd(II) ions could accelerate nZVI corrosion. The positively charged Fe3O4 and γ-FeOOH on corroded nZVI surface could facilitate the heteroaggregation of nZVI-SNPs by the patch-charge attraction, which further reduced the environmental risk of colloidal Cd(II) transport. These findings revealed the important effects of heteroaggregation between nZVI and SNPs on the transport risk of Cd(II) in groundwater.


Assuntos
Cádmio , Ferro , Cádmio/química , Ferro/química , Dióxido de Silício/química , Poluentes Químicos da Água/química , Solo/química , Nanopartículas Metálicas/química
8.
Sci China Life Sci ; 67(7): 1413-1426, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38565741

RESUMO

Endocrine therapy that blocks estrogen signaling is the most effective treatment for patients with estrogen receptor positive (ER+) breast cancer. However, the efficacy of agents such as tamoxifen (Tam) is often compromised by the development of resistance. Here we report that cytokines-activated nuclear IKKα confers Tam resistance to ER+ breast cancer by inducing the expression of FAT10, and that the expression of FAT10 and nuclear IKKα in primary ER+ human breast cancer was correlated with lymphotoxin ß (LTB) expression and significantly associated with relapse and metastasis in patients treated with adjuvant mono-Tam. IKKα activation or enforced FAT10 expression promotes Tam-resistance while loss of IKKα or FAT10 augments Tam sensitivity. The induction of FAT10 by IKKα is mediated by the transcription factor Pax5, and coordinated via an IKKα-p53-miR-23a circuit in which activation of IKKα attenuates p53-directed repression of FAT10. Thus, our findings establish IKKα-to-FAT10 pathway as a new therapeutic target for the treatment of Tam-resistant ER+ breast cancer.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Quinase I-kappa B , Transdução de Sinais , Tamoxifeno , Animais , Feminino , Humanos , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Citocinas/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinase I-kappa B/metabolismo , Células MCF-7 , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética
9.
Lab Med ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38447534

RESUMO

Hereditary factor VII (FVII) deficiency is an uncommon autosomal recessive disorder associated with mutations in the F7 gene, and laboratory investigations usually reveal isolated prolongation in prothrombin time (PT)/international normalized ratio (INR). Venom-induced consumptive coagulopathy (VICC) is distinguished by the activation of the coagulation pathway, which is triggered by procoagulant toxins in snake venom. Diagnosing snakebites in patients with hereditary FVII deficiency presents a challenge because prolonged time PT/INR is considered the most valuable diagnostic method for VICC. Therefore, it is possible that certain patients may not promptly receive an accurate diagnosis of hereditary FVII deficiency. We present a pedigree featuring hereditary FVII deficiency, which was diagnosed through Sanger sequencing, following a bamboo leaf green snake bite.

10.
J Invest Dermatol ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38462125

RESUMO

The function and survival of melanocytes is regulated by an elaborate network of paracrine factors synthesized mainly by epidermal keratinocytes (KCs). KCs and melanocytes respond to UV exposure by eliciting a tanning response. However, how KCs and melanocytes interact in the absence of UV exposure is unknown. In this study, we demonstrate that after SPRY1 knockout in epidermal KCs, melanocyte stem cells in the hair follicle exit the niche without depleting the pool of these cells. We also found that melanocyte stem cells migrate to the epidermis in a p53/stem cell factor/C-KIT-dependent manner induced by a tanning-like response resulting from SPRY1 loss in epidermal KCs. Once there, these cells differentiate into functional melanocytes. These findings provide an example in which the migration of melanocyte stem cells to the epidermis is due to loss of SPRY1 in epidermal KCs and show the potential for developing therapies for skin pigmentation disorders by manipulating melanocyte stem cells.

11.
Heliyon ; 10(6): e28283, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38524603

RESUMO

Abscisic acid (ABA) is a plant hormone with various biological activities. Aging is a natural process accompanied by cognitive and physiological decline, and aging and its associated diseases pose a serious threat to public health, but its mechanisms remain insufficient. Therefore, the purpose of this study was to investigate the ameliorative effects of ABA on d-galactose (D-Gal)-induced aging in mice and to delve into its molecular mechanisms. Aging model was es-tablished by theintraperitoneal injection of D-Gal. We evaluated the oxidative stress by measuring superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) levels in serum. Proteins content in brain were determined by Western blot. D-Gal-induced brain damage was monitored by measuring the levels of acetylcholinesterase (AChE) content and hematoxylin-eosin staining (H&E). To evaluate the effects of ABA on aging, we measured the gut microbiota. The results demonstrated that ABA increased SOD, CAT and AChE, decreased MDA level. H&E staining showed that ABA could improve D-Gal-induced damage. In addition, ABA regulated the B-cell-lymphoma-2 (BCL-2) family and Phosphatidylinositol 3-kinase/Protein kinase B (PI3K/AKT) signaling pathway, while further regulating the acetylation of p53 protein by modulating the AMPK pathway and activating SIRT1 protein, thereby inhibiting the apoptosis of brain neurons and thus regulating the aging process. Interestingly, ABA improved the ratio of intestinal bacteria involved in regulating multiple metabolic pathways in the aging process, such as Bacteroides, Firmicutes, Lactobacillus and Ak-kermansia. In conclusion, the present study suggests that ABA may be responsible for improving and delaying the aging process by enhancing antioxidant activity, anti-apoptosis and regulating intestinal flora.

12.
Mod Pathol ; 37(5): 100466, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460674

RESUMO

This manuscript represents a review of lymphoblastic leukemia/lymphoma (acute lymphoblastic leukemia/lymphoblastic lymphoma), acute leukemias of ambiguous lineage, mixed-phenotype acute leukemias, myeloid/lymphoid neoplasms with eosinophilia and defining gene rearrangements, histiocytic and dendritic neoplasms, and genetic tumor syndromes of the 5th edition of the World Health Organization Classification of Tumors of the Hematopoietic and Lymphoid Tissues. The diagnostic, clinicopathologic, cytogenetic, and molecular genetic features are discussed. The differences in comparison to the 4th revised edition of the World Health Organization classification of hematolymphoid neoplasms are highlighted.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Organização Mundial da Saúde , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/classificação , Eosinofilia/patologia , Eosinofilia/genética , Transtornos Histiocíticos Malignos/genética , Transtornos Histiocíticos Malignos/patologia , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Neoplasias Hematológicas/classificação , Fenótipo
13.
Cell Rep ; 43(2): 113723, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38300801

RESUMO

Stop codon readthrough (SCR) has important biological implications but remains largely uncharacterized. Here, we identify 1,009 SCR events in plants using a proteogenomic strategy. Plant SCR candidates tend to have shorter transcript lengths and fewer exons and splice variants than non-SCR transcripts. Mass spectrometry evidence shows that stop codons involved in SCR events can be recoded as 20 standard amino acids, some of which are also supported by suppressor tRNA analysis. We also observe multiple functional signals in 34 maize extended proteins and characterize the structural and subcellular localization changes in the extended protein of basic transcription factor 3. Furthermore, the SCR events exhibit non-conserved signature, and the extensions likely undergo protein-coding selection. Overall, our study not only characterizes that SCR events are commonly present in plants but also identifies the recoding plasticity of stop codons, which provides important insights into the flexibility of genetic decoding.


Assuntos
Biossíntese de Proteínas , Proteínas , Códon de Terminação/genética , Proteínas/genética , Aminoácidos/genética , RNA de Transferência/genética
14.
Heliyon ; 10(1): e23309, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38169889

RESUMO

Background: Adipokines and inflammatory cytokines (ADICs) play important roles in type 2 diabetes mellitus (T2DM). This study aimed to compare the changes of ADIC levels (ΔADICs) in patients with newly diagnosed T2DM treated with different antihyperglycemic agents, and further investigate the impact of these changes on metabolic indices, ß-cell function and insulin resistance (IR). Methods: Four hundred and sixteen patients with newly diagnosed T2DM from 25 centers in China randomly received 48-week intervention with exenatide, insulin or pioglitazone. Anthropometric and laboratory data, indices of ß-cell function and IR, and levels of AIDCs, including interleukin-1 beta (IL-1ß), interferon-gamma (IFN-γ), leptin, and fibroblast growth factor 21 (FGF21) were detected at baseline and the end of the study. Results: In total, 281 participants (68 % male, age: 50.3 ± 9.4 years) completed the study. After 48- week treatment, IL-1ß and IFN-γ were significantly decreased with exenatide treatment (P < 0.001 and P = 0.001, respectively), but increased with insulin (P = 0.009 and P = 0.026, respectively). However, pioglitazone treatment had no impact on ADICs. No significant change in leptin or FGF21 was detected with any of the treatments. After adjustment for baseline values and changes of body weight, waist and HbA1c, the between-group differences were found in ΔIL-1ß (exenatide vs. insulin: P = 0.048; and exenatide vs. pioglitazone: P = 0.003, respectively) and ΔIFN-γ (exenatide vs. insulin: P = 0.049; and exenatide vs. pioglitazone: P < 0.001, respectively). Multiple linear regression analysis indicated that Δweight was associated with ΔIL-1ß (ß = 0.753; 95 % CI, 0.137-1.369; P = 0.017). After adjusting for treatment effects, Δweight was also be correlated with ΔFGF21 (ß = 1.097; 95%CI, 0.250-1.944; P = 0.012); furthermore, ΔHOMA-IR was correlated with Δleptin (ß = 0.078; 95%CI, 0.008-0.147; P = 0.029) as well. However, ΔHOMA-IR was not significantly associated with ΔIL-1ß after adjusting for treatment effects (P = 0.513). Conclusion: Exenatide treatment led to significant changes of inflammatory cytokines levels (IL-1ß and IFN-γ), but not adipokines (leptin and FGF21), in newly diagnosed T2DM patients. The exenatide-mediated improvement in weight and IR may be associated with a decrease in inflammatory cytokine levels.

15.
J Invest Dermatol ; 144(4): 774-785.e10, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37827278

RESUMO

Psoriasis is characterized by excessive keratinocyte proliferation and immunocyte infiltration, but the underlying pathogenesis remains unclear. Aminoacyl-tRNA synthetases are universally expressed enzymes that catalyze the first step of protein synthesis. Glycyl-tRNA synthetase (GARS) is a member of the aminoacyl-tRNA synthetase family. In addition to its canonical function, we found that GARS was overexpressed in the serum and skin lesions of patients with psoriasis. Moreover, GARS was highly expressed in human skin keratinocytes, and GARS knockdown in keratinocytes suppressed cell proliferation and promoted apoptosis through NF-κB/MAPK signaling pathway. Moreover, intradermal injection of recombinant GARS protein caused skin thickening, angiogenesis, and IFN/TNF-driven skin inflammation. Intriguingly, the reported functional receptor for GARS, cadherin 6 (CDH6), was specifically expressed in vascular endothelial cells, and we found that keratinocyte-derived GARS promotes inflammation and angiogenesis of vascular endothelial cells through CDH6. In addition, intradermal injection of GARS aggravated the phenotype and angiogenesis in imiquimod-induced psoriasiform dermatitis models, whereas the psoriatic phenotype and angiogenesis were relieved after knockdown of GARS by adeno-associated virus. Taken together, the results of this study identify the critical role of GARS in the pathogenesis of psoriasis and suggest that blocking GARS may be a therapeutic approach for alleviating psoriasis.


Assuntos
Dermatite , Glicina-tRNA Ligase , Psoríase , Humanos , Angiogênese , Dermatite/patologia , Células Endoteliais/patologia , Glicina-tRNA Ligase/genética , Glicina-tRNA Ligase/metabolismo , Inflamação/patologia , Queratinócitos/metabolismo , Psoríase/patologia , Pele/patologia
16.
J Environ Sci (China) ; 138: 709-718, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135433

RESUMO

Formaldehyde (HCHO) is a common indoor pollutant that is detrimental to human health. Its efficient removal has become an urgent demand to reduce the public health risk. In this work, Ag-MnOx-based catalysts were prepared and activated under different atmosphere (i.e., air, hydrogen (H2) and carbon monoxide (CO)) for efficient oxidation of HCHO. The catalyst activated with CO (Ag/Mn-CO) displayed the highest activity among the tested samples with 90% conversion at 100°C under a gas space velocity of 75,000 mL/(gcat·hr). Complementary characterizations demonstrate that CO reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate HCHO and size of Ag particle to dissociate oxygen to oxidize the adsorbed HCHO. In contrast, other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size, so that the integrate activity is limited by one specific reaction step. This study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.


Assuntos
Oxigênio , Prata , Humanos , Óxidos , Oxirredução , Formaldeído , Catálise
17.
ACS Appl Mater Interfaces ; 16(1): 605-613, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38131347

RESUMO

The catalytic oxidation of carbon monoxide (CO) under ambient conditions plays a crucial role in the abatement of indoor CO, which poses risks to human health. Despite the notable activity exhibited by Pt-based catalysts in CO oxidation, their efficacy is usually diminished by the CO self-poisoning issue. In this work, three different Pt/CeO2-based catalysts, which have distinct coordinative environments of Pt but an identical Pt/CeO2 substrate structure, were synthesized by activating the catalyst with CO using different temperatures and durations. Compared with clean and graphite-covered Pt on CeO2, the one modified by epoxy carbon showed higher activity and stability. The combination of characterizations and density functional theory modeling demonstrated that the clean Pt on CeO2 rapidly deactivated due to the CO self-poisoning albeit high initial activity, and conversely, low initial activity was observed for the more stable graphite-covered catalyst due to the obstruction of the Pt site. In contrast, epoxy carbon species on Pt shifted the d-band of Pt to lower energy, weakening the Pt-CO binding strength. Such a modification mitigated the self-poisoning effect while maintaining ample active sites and enabling the complete oxidative removal of CO under ambient conditions. This work may provide a general approach to tackling the self-poisoning issue.

19.
Sci Data ; 10(1): 873, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057329

RESUMO

Lithocarpus, with >320 species, is the second largest genus of Fagaceae. However, the lack of a reference genome limits the molecular biology and functional study of Lithocarpus species. Here, we report the chromosome-scale genome assembly of sweet tea (Lithocarpus polystachyus Rehder), the first Lithocarpus species to be sequenced to date. Sweet tea has a 952-Mb genome, with a 21.4-Mb contig N50 value and 98.6% complete BUSCO score. In addition, the per-base consensus accuracy and completeness of the genome were estimated at 60.6 and 81.4, respectively. Genome annotation predicted 37,396 protein-coding genes, with repetitive sequences accounting for 64.2% of the genome. The genome did not undergo whole-genome duplication after the gamma (γ) hexaploidy event. Phylogenetic analysis showed that sweet tea diverged from the genus Quercus approximately at 59 million years ago. The high-quality genome assembly and gene annotation resources enrich the genomics of sweet tea, and will facilitate functional genomic studies in sweet tea and other Fagaceae species.


Assuntos
Genoma de Planta , Quercus , Cromossomos , Anotação de Sequência Molecular , Filogenia , Quercus/genética , Chá
20.
Front Immunol ; 14: 1273182, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38053996

RESUMO

Atopic dermatitis (AD) is one of the most common inflammatory skin diseases with complex pathogenesis involving epidermal barrier dysfunction, skin microbiome abnormalities and type-2-skewed immune dysregulation. Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that plays critical roles in various biological processes. However, the role of STAT3 in epidermal keratinocytes in AD remains unclear. In this study, we generated an epidermal keratinocyte-specific Stat3-deficient mouse strain (termed Stat3 cKO mice). After topical 2,4-dinitrochlorobenzene (DNCB) treatment, Stat3 cKO mice developed worsened AD-like skin inflammation with increased Ki67+ cells, decreased filaggrin and loricrin expression, and downregulated S100A9 and LL37. The dominant microbial population in Stat3 cKO mice changed from Ralstonia to Staphylococcus. DNCB-treated Stat3 cKO mice displayed more infiltrating type-2 inflammatory cells, including mast cells, eosinophils, and CD4+T cells, accompanied by increased skin IL-4 and serum IgE levels. Moreover, thymic stromal lymphopoietin (TSLP), mainly produced by keratinocytes, was highly expressed in the ear skin of Stat3 cKO mice and chemoattracted more TSLPR+ cells. TSLP blockade significantly alleviated DNCB-induced AD-like skin inflammation in Stat3 cKO mice. Thus, epidermal keratinocyte-specific STAT3 deficiency can aggravate AD-like skin inflammation in mice, possibly through TSLP dysregulation.


Assuntos
Dermatite Atópica , Animais , Camundongos , Citocinas/metabolismo , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/genética , Dinitroclorobenzeno , Inflamação/metabolismo , Queratinócitos , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Linfopoietina do Estroma do Timo , Regulação para Cima
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