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1.
Nat Immunol ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39025963

RESUMO

Germinal centers (GCs) that form in mucosal sites are exposed to gut-derived factors that have the potential to influence homeostasis independent of antigen receptor-driven selective processes. The G-protein Gα13 confines B cells to the GC and limits the development of GC-derived lymphoma. We discovered that Gα13-deficiency fuels the GC reaction via increased mTORC1 signaling and Myc protein expression specifically in the mesenteric lymph node (mLN). The competitive advantage of Gα13-deficient GC B cells (GCBs) in mLN was not dependent on T cell help or gut microbiota. Instead, Gα13-deficient GCBs were selectively dependent on dietary nutrients likely due to greater access to gut lymphatics. Specifically, we found that diet-derived glutamine supported proliferation and Myc expression in Gα13-deficient GCBs in the mLN. Thus, GC confinement limits the effects of dietary glutamine on GC dynamics in mucosal tissues. Gα13 pathway mutations coopt these processes to promote the gut tropism of aggressive lymphoma.

2.
Cancer Cell ; 42(7): 1185-1201.e14, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38906156

RESUMO

Multiple myeloma (MM) is an incurable plasma cell malignancy that exploits transcriptional networks driven by IRF4. We employ a multi-omics approach to discover IRF4 vulnerabilities, integrating functional genomics screening, spatial proteomics, and global chromatin mapping. ARID1A, a member of the SWI/SNF chromatin remodeling complex, is required for IRF4 expression and functionally associates with IRF4 protein on chromatin. Deleting Arid1a in activated murine B cells disrupts IRF4-dependent transcriptional networks and blocks plasma cell differentiation. Targeting SWI/SNF activity leads to rapid loss of IRF4-target gene expression and quenches global amplification of oncogenic gene expression by MYC, resulting in profound toxicity to MM cells. Notably, MM patients with aggressive disease bear the signature of SWI/SNF activity, and SMARCA2/4 inhibitors remain effective in immunomodulatory drug (IMiD)-resistant MM cells. Moreover, combinations of SWI/SNF and MEK inhibitors demonstrate synergistic toxicity to MM cells, providing a promising strategy for relapsed/refractory disease.


Assuntos
Proteínas de Ligação a DNA , Fatores Reguladores de Interferon , Mieloma Múltiplo , Plasmócitos , Fatores de Transcrição , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Fatores Reguladores de Interferon/metabolismo , Fatores Reguladores de Interferon/genética , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Humanos , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Plasmócitos/efeitos dos fármacos , Plasmócitos/metabolismo , Plasmócitos/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linhagem Celular Tumoral , Diferenciação Celular/efeitos dos fármacos
3.
N Engl J Med ; 390(23): 2143-2155, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899693

RESUMO

BACKGROUND: The identification of oncogenic mutations in diffuse large B-cell lymphoma (DLBCL) has led to the development of drugs that target essential survival pathways, but whether targeting multiple survival pathways may be curative in DLBCL is unknown. METHODS: We performed a single-center, phase 1b-2 study of a regimen of venetoclax, ibrutinib, prednisone, obinutuzumab, and lenalidomide (ViPOR) in relapsed or refractory DLBCL. In phase 1b, which included patients with DLBCL and indolent lymphomas, four dose levels of venetoclax were evaluated to identify the recommended phase 2 dose, with fixed doses of the other four drugs. A phase 2 expansion in patients with germinal-center B-cell (GCB) and non-GCB DLBCL was performed. ViPOR was administered every 21 days for six cycles. RESULTS: In phase 1b of the study, involving 20 patients (10 with DLBCL), a single dose-limiting toxic effect of grade 3 intracranial hemorrhage occurred, a result that established venetoclax at a dose of 800 mg as the recommended phase 2 dose. Phase 2 included 40 patients with DLBCL. Toxic effects that were observed among all the patients included grade 3 or 4 neutropenia (in 24% of the cycles), thrombocytopenia (in 23%), anemia (in 7%), and febrile neutropenia (in 1%). Objective responses occurred in 54% of 48 evaluable patients with DLBCL, and complete responses occurred in 38%; complete responses were exclusively in patients with non-GCB DLBCL and high-grade B-cell lymphoma with rearrangements of MYC and BCL2 or BCL6 (or both). Circulating tumor DNA was undetectable in 33% of the patients at the end of ViPOR therapy. With a median follow-up of 40 months, 2-year progression-free survival and overall survival were 34% (95% confidence interval [CI], 21 to 47) and 36% (95% CI, 23 to 49), respectively. CONCLUSIONS: Treatment with ViPOR was associated with durable remissions in patients with specific molecular DLBCL subtypes and was associated with mainly reversible adverse events. (Funded by the Intramural Research Program of the National Cancer Institute and the National Center for Advancing Translational Sciences of the National Institutes of Health and others; ClinicalTrials.gov number, NCT03223610.).


Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Lenalidomida , Linfoma Difuso de Grandes Células B , Piperidinas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adenina/análogos & derivados , Adenina/efeitos adversos , Adenina/uso terapêutico , Adenina/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Lenalidomida/efeitos adversos , Lenalidomida/administração & dosagem , Lenalidomida/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Terapia de Alvo Molecular , Piperidinas/efeitos adversos , Piperidinas/uso terapêutico , Piperidinas/administração & dosagem , Prednisona/efeitos adversos , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Intervalo Livre de Progressão , Pirazóis/efeitos adversos , Pirazóis/uso terapêutico , Pirazóis/administração & dosagem , Pirimidinas/efeitos adversos , Pirimidinas/uso terapêutico , Pirimidinas/administração & dosagem , Recidiva , Sulfonamidas/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico
4.
Mucosal Immunol ; 17(4): 700-712, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38729611

RESUMO

Resident memory T cells (TRMs) help control local immune homeostasis and contribute to tissue-protective immune responses. The local cues that guide their differentiation and localization are poorly defined. We demonstrate that mucosal vascular addressin cell adhesion molecule 1, a ligand for the gut-homing receptor α4ß7 integrin, in the presence of retinoic acid and transforming growth factor-ß (TGF-ß) provides a co-stimulatory signal that induces blood cluster of differentiation (CD8+ T cells to adopt a TRM-like phenotype. These cells express CD103 (integrin αE) and CD69, the two major TRM cell-surface markers, along with CD101. They also express C-C motif chemokine receptors 5 (CCR5) , C-C motif chemokine receptors 9 (CCR9), and α4ß7, three receptors associated with gut homing. A subset also expresses E-cadherin, a ligand for αEß7. Fluorescent lifetime imaging indicated an αEß7 and E-cadherin cis interaction on the plasma membrane. This report advances our understanding of the signals that drive the differentiation of CD8+ T cells into resident memory T cells and provides a means to expand these cells in vitro, thereby affording an avenue to generate more effective tissue-specific immunotherapies.


Assuntos
Antígenos CD , Antígenos de Diferenciação de Linfócitos T , Linfócitos T CD8-Positivos , Cadeias alfa de Integrinas , Fator de Crescimento Transformador beta , Tretinoína , Tretinoína/farmacologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Camundongos , Cadeias alfa de Integrinas/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Memória Imunológica , Moléculas de Adesão Celular/metabolismo , Caderinas/metabolismo , Lectinas Tipo C/metabolismo , Diferenciação Celular , Mucoproteínas/metabolismo , Receptores CCR/metabolismo , Células T de Memória/imunologia , Células T de Memória/metabolismo , Imunoglobulinas/metabolismo , Camundongos Endogâmicos C57BL , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Integrinas/metabolismo , Fenótipo
5.
Cancer Cell ; 42(5): 833-849.e12, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38701792

RESUMO

Glucocorticoids have been used for decades to treat lymphomas without an established mechanism of action. Using functional genomic, proteomic, and chemical screens, we discover that glucocorticoids inhibit oncogenic signaling by the B cell receptor (BCR), a recurrent feature of aggressive B cell malignancies, including diffuse large B cell lymphoma and Burkitt lymphoma. Glucocorticoids induce the glucocorticoid receptor (GR) to directly transactivate genes encoding negative regulators of BCR stability (LAPTM5; KLHL14) and the PI3 kinase pathway (INPP5D; DDIT4). GR directly represses transcription of CSK, a kinase that limits the activity of BCR-proximal Src-family kinases. CSK inhibition attenuates the constitutive BCR signaling of lymphomas by hyperactivating Src-family kinases, triggering their ubiquitination and degradation. With the knowledge that glucocorticoids disable oncogenic BCR signaling, they can now be deployed rationally to treat BCR-dependent aggressive lymphomas and used to construct mechanistically sound combination regimens with inhibitors of BTK, PI3 kinase, BCL2, and CSK.


Assuntos
Glucocorticoides , Receptores de Antígenos de Linfócitos B , Humanos , Glucocorticoides/farmacologia , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Transdução de Sinais/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Camundongos , Linhagem Celular Tumoral , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/genética , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Terapia de Alvo Molecular/métodos , Fosfatidilinositol 3-Quinases/metabolismo , Quinases da Família src/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
6.
Cancer Cell ; 42(3): 444-463.e10, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38428410

RESUMO

Follicular lymphoma (FL) is a generally incurable malignancy that evolves from developmentally blocked germinal center (GC) B cells. To promote survival and immune escape, tumor B cells undergo significant genetic changes and extensively remodel the lymphoid microenvironment. Dynamic interactions between tumor B cells and the tumor microenvironment (TME) are hypothesized to contribute to the broad spectrum of clinical behaviors observed among FL patients. Despite the urgent need, existing clinical tools do not reliably predict disease behavior. Using a multi-modal strategy, we examined cell-intrinsic and -extrinsic factors governing progression and therapeutic outcomes in FL patients enrolled onto a prospective clinical trial. By leveraging the strengths of each platform, we identify several tumor-specific features and microenvironmental patterns enriched in individuals who experience early relapse, the most high-risk FL patients. These features include stromal desmoplasia and changes to the follicular growth pattern present 20 months before first progression and first relapse.


Assuntos
Linfoma Folicular , Humanos , Linfócitos B , Linfoma Folicular/genética , Multiômica , Estudos Prospectivos , Recidiva , Microambiente Tumoral , Ensaios Clínicos como Assunto
7.
Food Res Int ; 176: 113813, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163717

RESUMO

The proteins were mainly derived from Protaetia brevitarsis larval extracts obtained using two empty intestine methods (traditional static method: TSM or salt immersion stress method: SISM) and extraction solvents (water: W or 50 % water-ethanol: W:E), and the proteins were used as objects to investigate the effect of emptying intestine methods on hypolipidemic peptides. The results revealed that the F-2 fractions of protein hydrolysate had stronger in vitro hypolipidemic activity, with the peptides obtained by SISM possessing a stronger cholesterol micelle solubility inhibition rate, especially in SISM-W:E-P. Moreover, a total of 106 peptides were tentatively identified, among which SISM identified more peptides with an amino acid number < 8. Meanwhile, five novel peptides (YPPFH, YPGFGK, KYPF, SPLPGPR and VPPP) exhibited good hypolipidemic activity in vitro and in vivo, among which YPPFH, VPPP and KYPF had strong inhibitory activities on pancreatic lipase (PL) and cholesteryl esterase (CE), and KYPF, SPLPGPR and VPPP could significantly reduce the TG content in Caenorhabditis elegans. Thus, P. brevitarsis can be developed as a naturally derived hypolipidemic component for the development and application in functional foods.


Assuntos
Besouros , Hidrolisados de Proteína , Animais , Larva/química , Hidrolisados de Proteína/farmacologia , Hidrolisados de Proteína/metabolismo , Besouros/química , Peptídeos/farmacologia , Peptídeos/metabolismo , Água/metabolismo , Proteínas de Insetos/farmacologia , Proteínas de Insetos/metabolismo
8.
Cancer Cell ; 42(2): 238-252.e9, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38215749

RESUMO

Diffuse large B cell lymphoma (DLBCL) is an aggressive, profoundly heterogeneous cancer, presenting a challenge for precision medicine. Bruton's tyrosine kinase (BTK) inhibitors block B cell receptor (BCR) signaling and are particularly effective in certain molecular subtypes of DLBCL that rely on chronic active BCR signaling to promote oncogenic NF-κB. The MCD genetic subtype, which often acquires mutations in the BCR subunit, CD79B, and in the innate immune adapter, MYD88L265P, typically resists chemotherapy but responds exceptionally to BTK inhibitors. However, the underlying mechanisms of response to BTK inhibitors are poorly understood. Herein, we find a non-canonical form of chronic selective autophagy in MCD DLBCL that targets ubiquitinated MYD88L265P for degradation in a TBK1-dependent manner. MCD tumors acquire genetic and epigenetic alterations that attenuate this autophagic tumor suppressive pathway. In contrast, BTK inhibitors promote autophagic degradation of MYD88L265P, thus explaining their exceptional clinical benefit in MCD DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B , Humanos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/farmacologia , Transdução de Sinais , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Autofagia
9.
Blood ; 142(15): 1297-1311, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37339580

RESUMO

Anaplastic large cell lymphoma (ALCL), a subgroup of mature T-cell neoplasms with an aggressive clinical course, is characterized by elevated expression of CD30 and anaplastic cytology. To achieve a comprehensive understanding of the molecular characteristics of ALCL pathology and to identify therapeutic vulnerabilities, we applied genome-wide CRISPR library screenings to both anaplastic lymphoma kinase positive (ALK+) and primary cutaneous (pC) ALK- ALCLs and identified an unexpected role of the interleukin-1R (IL-1R) inflammatory pathway in supporting the viability of pC ALK- ALCL. Importantly, this pathway is activated by IL-1α in an autocrine manner, which is essential for the induction and maintenance of protumorigenic inflammatory responses in pC-ALCL cell lines and primary cases. Hyperactivation of the IL-1R pathway is promoted by the A20 loss-of-function mutation in the pC-ALCL lines we analyze and is regulated by the nonproteolytic protein ubiquitination network. Furthermore, the IL-1R pathway promotes JAK-STAT3 signaling activation in ALCLs lacking STAT3 gain-of-function mutation or ALK translocation and enhances the sensitivity of JAK inhibitors in these tumors in vitro and in vivo. Finally, the JAK2/IRAK1 dual inhibitor, pacritinib, exhibited strong activities against pC ALK- ALCL, where the IL-1R pathway is hyperactivated in the cell line and xenograft mouse model. Thus, our studies revealed critical insights into the essential roles of the IL-1R pathway in pC-ALCL and provided opportunities for developing novel therapeutic strategies.


Assuntos
Linfoma Anaplásico de Células Grandes , Linfoma Anaplásico Cutâneo Primário de Células Grandes , Neoplasias Cutâneas , Humanos , Animais , Camundongos , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/patologia , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico/genética , Interleucinas/metabolismo
10.
Cancer Discov ; 13(8): 1862-1883, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37141112

RESUMO

Diffuse large B-cell lymphoma (DLBCL) can be subdivided into the activated B-cell (ABC) and germinal center B cell-like (GCB) subtypes. Self-antigen engagement of B-cell receptors (BCR) in ABC tumors induces their clustering, thereby initiating chronic active signaling and activation of NF-κB and PI3 kinase. Constitutive BCR signaling is essential in some GCB tumors but primarily activates PI3 kinase. We devised genome-wide CRISPR-Cas9 screens to identify regulators of IRF4, a direct transcriptional target of NF-κB and an indicator of proximal BCR signaling in ABC DLBCL. Unexpectedly, inactivation of N-linked protein glycosylation by the oligosaccharyltransferase-B (OST-B) complex reduced IRF4 expression. OST-B inhibition of BCR glycosylation reduced BCR clustering and internalization while promoting its association with CD22, which attenuated PI3 kinase and NF-κB activation. By directly interfering with proximal BCR signaling, OST-B inactivation killed models of ABC and GCB DLBCL, supporting the development of selective OST-B inhibitors for the treatment of these aggressive cancers. SIGNIFICANCE: DLBCL depends on constitutive BCR activation and signaling. There are currently no therapeutics that target the BCR directly and attenuate its pathologic signaling. Here, we unraveled a therapeutically exploitable, OST-B-dependent glycosylation pathway that drives BCR organization and proximal BCR signaling. This article is highlighted in the In This Issue feature, p. 1749.


Assuntos
Linfoma Difuso de Grandes Células B , NF-kappa B , Humanos , NF-kappa B/metabolismo , Glicosilação , Transdução de Sinais , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral
11.
Zool Res ; 44(3): 467-482, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-36994537

RESUMO

Chalcidoidea is one of the most biologically diverse groups among Hymenoptera. Members are characterized by extraordinary parasitic lifestyles and extensive host ranges, among which several species attack plants or serve as pollinators. However, higher-level chalcidoid relationships remain controversial. Here, we performed mitochondrial phylogenomic analyses for major clades (18 out of 25 families) of Chalcidoidea based on 139 mitochondrial genomes. The compositional heterogeneity and conflicting backbone relationships in Chalcidoidea were assessed using various datasets and tree inferences. Our phylogenetic results supported the monophyly of 16 families and polyphyly of Aphelinidae and Pteromalidae. Our preferred topology recovered the relationship (Mymaridae+(Signiphoridae+Leucospidae)+(Chalcididae+((Perilampidae+Eucharitidae)+ remaining Chalcidoidea)))). The monophyly of Agaonidae and Sycophaginae was rejected, while the gall-associated ((Megastigmidae+Ormyridae)+(Ormocerinae+Eurytomidae)) relationship was supported in most results. A six-gene inversion may be a synapomorphy for most families, whereas other derived gene orders may introduce confusion in phylogenetic signals at deeper nodes. Dating estimates suggested that Chalcidoidea arose near the Jurassic/Cretaceous boundary and that two dynamic shifts in diversification occurred during the evolution of Chalcidoidea. We hypothesized that the potential codiversification between chalcidoids and their hosts may be crucial for accelerating the diversification of Chalcidoidea. Ancestral state reconstruction analyses supported the hypothesis that gall-inducers were mainly derived from parasitoids of gall-inducers, while other gall-inducers were derived from phytophagous groups. Taken together, these findings advance our understanding of mitochondrial genome evolution in the major interfamilial phylogeny of Chalcidoidea.


Assuntos
Genoma Mitocondrial , Vespas , Animais , Vespas/genética , Filogenia , Genoma Mitocondrial/genética
13.
Food Chem ; 405(Pt B): 134891, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36403468

RESUMO

Intestinal contents affect the characterization of edible insect bioactive compounds. Two empty intestine methods, namely, traditional static method (TSM) or salt immersion stress method (SISM), associated with extraction solvents water (W), 50 % water-ethanol (W:E) or 100 % ethanol (E), were used to obtain six Protaetia brevitarsis larval extracts. The total flavonoid content (TFC) in the W:E extracts was significantly higher than that in the W and E extracts, with TSM-W:E the highest (p < 0.05). The relative contents of 132 bioactive compounds, especially p-hydroxyphenylacetic acid, citric acid, and dehydroepiandrosterone, were different between TSM-W and SISM-W. TSM-W:E had significantly higher 2,2-diphenyl-1-picrylhydroxy· (DPPH) scavenging and pancreatic lipase (PL) inhibitory activity than SISM-W:E (p < 0.05). DPPH scavenging and PL inhibitory activities were highly correlated with TFC and carbohydrates, respectively. Thus, bioactive compounds in P. brevitarsis extracts can be obtained selectively using pretreatment methods, which might be beneficial for high-value utilization of P. brevitarsis.


Assuntos
Besouros , Insetos Comestíveis , Animais , Larva , Ácido Cítrico , Etanol , Flavonoides , Lipase
14.
J Hazard Mater ; 445: 130481, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36493653

RESUMO

Highly efficient charge transfer is a critical factor to modulate the photocatalytic activity. However, the conscious modulation of charge transfer efficiency is still a great challenge. Herein, a novel interfacial Mo-N bond and appropriate oxygen vacancies (OVs) modulated S-scheme MoO3-x/S-CN heterojunction was rationally fabricated for efficient photocatalytic disinfection. The results of characterizations and density functional theory (DFT) calculations suggested that the enhanced charge transfer dynamics is ascribed to the optimizing oxygen vacancies density and forming interfacial Mo-N bond. It can improve charge transfer efficiency from 36.4% (MoO3-x) to 52.5% (MoO3-x/S-CN) and produce more reactive oxygen species (ROS), achieving entirely inactivate of 7.60-log E. coli and S. aureus within 50 min and 75 min. Besides, MoO3-x/S-CN can well resist the disturbance from the coexisting substances, and can be applied in a wide pH range, and even authentic water bodies. Monitoring of bacterial antioxidant systems and membrane integrity revealed that bacterial inactivation begins with the oxidation of cell membrane and dies from leakage of intracellular substances and destruction of cell structure. This work provides an inspiration on consciously modulating S-scheme charge transfer efficiency by optimizing oxygen vacancies density and atomic-level interface control for promoting the photocatalytic antibacterial activity.


Assuntos
Desinfecção , Oxigênio , Escherichia coli , Staphylococcus aureus , Espécies Reativas de Oxigênio
16.
Open Biol ; 12(9): 220108, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36167086

RESUMO

In animals, starvation can increase the level of reactive oxygen species (ROS) in some tissues. Mitochondrial DNA (mtDNA) is more vulnerable to being attacked by ROS due to the lack of histone protection, leading to oxidative damage. However, whether starvation is associated with the genetic diversity of mtDNA remains unclear. Here, by using adult individuals of Drosophila melanogaster under three different feeding treatments (starvation, with the provision of only water, and normal feeding), based on the high-throughput sequencing results of the PCR amplicons of the partial sequences of the mitochondrial gene cytochrome c oxidase subunit I (mt-cox1), no significant difference in the mean number of mitochondrial haplotypes and the mean genetic distance of haplotypes within individuals were identified between the three treatment groups. Coupled with the low proportion of heterogeneous mt-cox1 sequences within each individual, it suggested that starvation had a limited impact on mitotype genetic diversity and mitochondrial function. Nevertheless, starvation could significantly increase the sequence number of haplotypes containing specific mutations, and for males with higher levels of mitochondrial heteroplasmy than females in the normal feeding group, starvation could further increase their mitochondrial heteroplasmy.


Assuntos
Drosophila melanogaster , Complexo IV da Cadeia de Transporte de Elétrons , Animais , DNA Mitocondrial/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Histonas , Masculino , Espécies Reativas de Oxigênio/metabolismo , Água
17.
Nat Commun ; 13(1): 5469, 2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115844

RESUMO

Oncogenic RAS mutations are common in multiple myeloma (MM), an incurable malignancy of plasma cells. However, the mechanisms of pathogenic RAS signaling in this disease remain enigmatic and difficult to inhibit therapeutically. We employ an unbiased proteogenomic approach to dissect RAS signaling in MM. We discover that mutant isoforms of RAS organize a signaling complex with the amino acid transporter, SLC3A2, and MTOR on endolysosomes, which directly activates mTORC1 by co-opting amino acid sensing pathways. MM tumors with high expression of mTORC1-dependent genes are more aggressive and enriched in RAS mutations, and we detect interactions between RAS and MTOR in MM patient tumors harboring mutant RAS isoforms. Inhibition of RAS-dependent mTORC1 activity synergizes with MEK and ERK inhibitors to quench pathogenic RAS signaling in MM cells. This study redefines the RAS pathway in MM and provides a mechanistic and rational basis to target this mode of RAS signaling.


Assuntos
Genes ras , Mieloma Múltiplo , Fatores de Transcrição , Aminoácidos/metabolismo , Genes ras/genética , Genes ras/fisiologia , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mutação , Isoformas de Proteínas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Nanoscale Res Lett ; 17(1): 79, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36001189

RESUMO

Copper nanowires (CuNWs)-based thin film is one of the potential alternatives to tin-doped indium oxide (ITO) in terms of transparent conductive films (TCFs). However, the severe problem of atmospheric oxidation restricts their practical applications. In this work, we develop a simple approach to fabricate highly stable TCFs through the dip-coating method using reduced graphene oxide (rGO) and CuNWs as the primary materials. Compared with previous works using toxic reduction agents, herein, the CuNWs are synthesized via a green aqueous process using glucose and lactic acid as the reductants, and rGO is prepared through the modified Hummers' method followed by a hydrogen-annealing process to form hydrogen-annealing-reduced graphene oxide (h-rGO). In the rGO/CuNWs films, the dip-coated graphene oxide layer can increase the adhesion of the CuNWs on the substrate, and the fabricated h-rGO/CuNWs can exhibit high atmospheric oxidation resistance and excellent flexibility. The sheet resistance of the h-rGO/CuNWs film only increased from 25.1 to 42.2 Ω/sq after exposure to ambient atmosphere for 30 days and remained almost unchanged after the dynamic bending test for 2500 cycles at a constant radius of 5.3 mm. The h-rGO/CuNWs TCF can be not only fabricated via a route with a superior inexpensive and safe method but also possessed competitive optoelectronic properties with high electrical stability and flexibility, demonstrating great opportunities for future optoelectronic applications.

19.
J Hazard Mater ; 438: 129483, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35820331

RESUMO

Developing photocatalysts with superior performance to generate hydrogen peroxide (H2O2) and degrade oxytetracycline (OTC) is an effective strategy for the treatment of energy crisis and water purification. Herein, BN nanosheets were anchored onto the Zn3In2S6 microspheres for the research. Experimental and density functional theory (DFT) results demonstrate that due to different work functions and unique 2D/2D contact, the electron is spatially separated in BN/Zn3In2S6 nanocomposite, which increases the electron transfer efficiency from 43.7% (Zn3In2S6) to 55.6% (BN/ZIS-4). As a result, BN/ZIS-4 with optimal ratio of BN and Zn3In2S6 exhibits the highest OTC degradation efficiency (84.5%) and H2O2 generation rate (115.5 µmol L-1) under visible light illumination, which is 2.2 and 2.9 times than that of pristine Zn3In2S6. H2O2 generation is dominated by two pathways: two-step single-electron process (O2 → ∙O2- → H2O2) and another way (O2 → ∙O2- → 1O2 → H2O2). In the process of degrading OTC, ∙O2-, 1O2 and ∙OH are regarded as the main active species. This work offers a new insight for designing efficient, stable and reusable photocatalysts to solve current environmental conundrums.

20.
Mol Ecol Resour ; 22(8): 2967-2980, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35757869

RESUMO

DNA barcoding and metabarcoding have been increasingly used in species delimitation and species diversity assessment, respectively, and the molecular markers used in animals are mainly derived from mitochondrial DNA. It is well known that the phenomenon of multiple mitochondrial haplotypes within the same specimen (hereafter referred to as "mitotype diversity") may have a negative impact on the proper assessment of biodiversity by metabarcoding. However, few studies have focused on the incidence of this phenomenon and its effects on metabarcoding results using different sample preparation strategies, such as mock community construction using pooled high-throughput sequencing (HTS) data, DNA-pooling and Tissue-pooling. In this study, we investigated mitotype diversity and its influence on metabarcoding based on 398 specimens from 66 species of Insecta and 82 specimens from 16 species of Arachnida by HTS of the mitochondrial cox1 gene fragment. The results revealed that mitotype diversity was common in the studied taxa and significantly increased the number of operational taxonomic units (OTUs) using the three sample preparation strategies. The results also showed that the bioinformatics pipeline based on authentic amplicon sequence variants was more reliable than the pipeline based on OTUs. Regarding the sample preparation strategies of DNA-pooling and Tissue-pooling commonly used in metabarcoding, our results revealed that their results of metabarcoding were quite similar, and the Tissue-pooling strategy was therefore preferred because of its simplicity. Our study calls for additional attention to the interference of mitotype diversity on the results of DNA metabarcoding in biodiversity assessment.


Assuntos
Aracnídeos , Código de Barras de DNA Taxonômico , Animais , Biodiversidade , Código de Barras de DNA Taxonômico/métodos , DNA Mitocondrial/genética , Insetos/genética
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