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1.
Cell ; 185(7): 1172-1188.e28, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35303419

RESUMO

Intestinal mucus forms the first line of defense against bacterial invasion while providing nutrition to support microbial symbiosis. How the host controls mucus barrier integrity and commensalism is unclear. We show that terminal sialylation of glycans on intestinal mucus by ST6GALNAC1 (ST6), the dominant sialyltransferase specifically expressed in goblet cells and induced by microbial pathogen-associated molecular patterns, is essential for mucus integrity and protecting against excessive bacterial proteolytic degradation. Glycoproteomic profiling and biochemical analysis of ST6 mutations identified in patients show that decreased sialylation causes defective mucus proteins and congenital inflammatory bowel disease (IBD). Mice harboring a patient ST6 mutation have compromised mucus barriers, dysbiosis, and susceptibility to intestinal inflammation. Based on our understanding of the ST6 regulatory network, we show that treatment with sialylated mucin or a Foxo3 inhibitor can ameliorate IBD.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Sialiltransferases/genética , Animais , Homeostase , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Camundongos , Muco/metabolismo , Sialiltransferases/metabolismo , Simbiose
2.
Cell ; 179(2): 543-560.e26, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31585087

RESUMO

Tyrosine phosphorylation regulates multi-layered signaling networks with broad implications in (patho)physiology, but high-throughput methods for functional annotation of phosphotyrosine sites are lacking. To decipher phosphotyrosine signaling directly in tissue samples, we developed a mass-spectrometry-based interaction proteomics approach. We measured the in vivo EGF-dependent signaling network in lung tissue quantifying >1,000 phosphotyrosine sites. To assign function to all EGF-regulated sites, we determined their recruited protein signaling complexes in lung tissue by interaction proteomics. We demonstrated how mutations near tyrosine residues introduce molecular switches that rewire cancer signaling networks, and we revealed oncogenic properties of such a lung cancer EGFR mutant. To demonstrate the scalability of the approach, we performed >1,000 phosphopeptide pulldowns and analyzed them by rapid mass spectrometric analysis, revealing tissue-specific differences in interactors. Our approach is a general strategy for functional annotation of phosphorylation sites in tissues, enabling in-depth mechanistic insights into oncogenic rewiring of signaling networks.


Assuntos
Carcinogênese/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fosfotirosina/metabolismo , Células A549 , Animais , Humanos , Espectrometria de Massas/métodos , Mutação , Fosfoproteínas/metabolismo , Fosforilação , Proteômica , Ratos , Ratos Sprague-Dawley , Peixe-Zebra
3.
Nature ; 620(7976): 977-981, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37648759

RESUMO

Atomic defects in the solid state are a key component of quantum repeater networks for long-distance quantum communication1. Recently, there has been significant interest in rare earth ions2-4, in particular Er3+ for its telecom band optical transition5-7 that allows long-distance transmission in optical fibres. However, the development of repeater nodes based on rare earth ions has been hampered by optical spectral diffusion, precluding indistinguishable single-photon generation. Here, we implant Er3+ into CaWO4, a material that combines a non-polar site symmetry, low decoherence from nuclear spins8 and is free of background rare earth ions, to realize significantly reduced optical spectral diffusion. For shallow implanted ions coupled to nanophotonic cavities with large Purcell factor, we observe single-scan optical linewidths of 150 kHz and long-term spectral diffusion of 63 kHz, both close to the Purcell-enhanced radiative linewidth of 21 kHz. This enables the observation of Hong-Ou-Mandel interference9 between successively emitted photons with a visibility of V = 80(4)%, measured after a 36 km delay line. We also observe spin relaxation times T1,s = 3.7 s and T2,s > 200 µs, with the latter limited by paramagnetic impurities in the crystal instead of nuclear spins. This represents a notable step towards the construction of telecom band quantum repeater networks with single Er3+ ions.

4.
Nature ; 614(7946): 153-159, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36697829

RESUMO

Mitochondria have crucial roles in cellular energetics, metabolism, signalling and quality control1-4. They contain around 1,000 different proteins that often assemble into complexes and supercomplexes such as respiratory complexes and preprotein translocases1,3-7. The composition of the mitochondrial proteome has been characterized1,3,5,6; however, the organization of mitochondrial proteins into stable and dynamic assemblies is poorly understood for major parts of the proteome1,4,7. Here we report quantitative mapping of mitochondrial protein assemblies using high-resolution complexome profiling of more than 90% of the yeast mitochondrial proteome, termed MitCOM. An analysis of the MitCOM dataset resolves >5,200 protein peaks with an average of six peaks per protein and demonstrates a notable complexity of mitochondrial protein assemblies with distinct appearance for respiration, metabolism, biogenesis, dynamics, regulation and redox processes. We detect interactors of the mitochondrial receptor for cytosolic ribosomes, of prohibitin scaffolds and of respiratory complexes. The identification of quality-control factors operating at the mitochondrial protein entry gate reveals pathways for preprotein ubiquitylation, deubiquitylation and degradation. Interactions between the peptidyl-tRNA hydrolase Pth2 and the entry gate led to the elucidation of a constitutive pathway for the removal of preproteins. The MitCOM dataset-which is accessible through an interactive profile viewer-is a comprehensive resource for the identification, organization and interaction of mitochondrial machineries and pathways.


Assuntos
Proteínas Fúngicas , Mitocôndrias , Proteínas Mitocondriais , Transporte Proteico , Proteoma , Saccharomyces cerevisiae , Proteínas de Transporte/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteoma/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Fúngicas/metabolismo , Respiração Celular , Ribossomos , Conjuntos de Dados como Assunto
5.
Immunity ; 50(3): 567-575.e5, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30850342

RESUMO

Long-term delivery of anti-HIV monoclonal antibodies (mAbs) using adeno-associated virus (AAV) vectors holds promise for the prevention and treatment of HIV infection. We describe a therapy trial in which four rhesus monkeys were infected with SHIV-AD8 for 86 weeks before receiving the AAV-encoded mAbs 3BNC117, 10-1074, and 10E8. Although anti-drug antibody (ADA) responses restricted mAb delivery, one monkey successfully maintained 50-150 µg/mL of 3BNC117 and 10-1074 for over 2 years. Delivery of these two mAbs to this monkey resulted in an abrupt decline in plasma viremia, which remained undetectable for 38 successive measurements over 3 years. We generated two more examples of virologic suppression using AAV delivery of a cocktail of four mAbs in a 12-monkey study. Our results provide proof of concept for AAV-delivered mAbs to produce a "functional cure." However, they also serve as a warning that ADAs may be a problem for practical application of this approach in humans.


Assuntos
Anticorpos Monoclonais/imunologia , Dependovirus/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Animais , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes/imunologia , Anticorpos Amplamente Neutralizantes , Linhagem Celular , Células HEK293 , Anticorpos Anti-HIV/imunologia , Humanos , Macaca mulatta , Viremia/imunologia
6.
Cell ; 149(2): 371-82, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22500803

RESUMO

Growing microtubule ends serve as transient binding platforms for essential proteins that regulate microtubule dynamics and their interactions with cellular substructures. End-binding proteins (EBs) autonomously recognize an extended region at growing microtubule ends with unknown structural characteristics and then recruit other factors to the dynamic end structure. Using cryo-electron microscopy, subnanometer single-particle reconstruction, and fluorescence imaging, we present a pseudoatomic model of how the calponin homology (CH) domain of the fission yeast EB Mal3 binds to the end regions of growing microtubules. The Mal3 CH domain bridges protofilaments except at the microtubule seam. By binding close to the exchangeable GTP-binding site, the CH domain is ideally positioned to sense the microtubule's nucleotide state. The same microtubule-end region is also a stabilizing structural cap protecting the microtubule from depolymerization. This insight supports a common structural link between two important biological phenomena, microtubule dynamic instability and end tracking.


Assuntos
Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Sequência de Aminoácidos , Microscopia Crioeletrônica , Proteínas Associadas aos Microtúbulos/química , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Schizosaccharomyces/química , Proteínas de Schizosaccharomyces pombe/química , Alinhamento de Sequência , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
7.
Nature ; 590(7844): 163-169, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33408415

RESUMO

The mitochondrial outer membrane contains so-called ß-barrel proteins, which allow communication between the cytosol and the mitochondrial interior1-3. Insertion of ß-barrel proteins into the outer membrane is mediated by the multisubunit mitochondrial sorting and assembly machinery (SAM, also known as TOB)4-6. Here we use cryo-electron microscopy to determine the structures of two different forms of the yeast SAM complex at a resolution of 2.8-3.2 Å. The dimeric complex contains two copies of the ß-barrel channel protein Sam50-Sam50a and Sam50b-with partially open lateral gates. The peripheral membrane proteins Sam35 and Sam37 cap the Sam50 channels from the cytosolic side, and are crucial for the structural and functional integrity of the dimeric complex. In the second complex, Sam50b is replaced by the ß-barrel protein Mdm10. In cooperation with Sam50a, Sam37 recruits and traps Mdm10 by penetrating the interior of its laterally closed ß-barrel from the cytosolic side. The substrate-loaded SAM complex contains one each of Sam50, Sam35 and Sam37, but neither Mdm10 nor a second Sam50, suggesting that Mdm10 and Sam50b function as placeholders for a ß-barrel substrate released from Sam50a. Our proposed mechanism for dynamic switching of ß-barrel subunits and substrate explains how entire precursor proteins can fold in association with the mitochondrial machinery for ß-barrel assembly.


Assuntos
Microscopia Crioeletrônica , Mitocôndrias/química , Mitocôndrias/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Proteínas de Membrana/ultraestrutura , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/ultraestrutura , Modelos Moleculares , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Multimerização Proteica , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/ultraestrutura
8.
Proc Natl Acad Sci U S A ; 119(50): e2211536119, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36469763

RESUMO

Understanding where in the cytoplasm mRNAs are translated is increasingly recognized as being as important as knowing the timing and level of protein expression. mRNAs are localized via active motor-driven transport along microtubules (MTs) but the underlying essential factors and dynamic interactions are largely unknown. Using biochemical in vitro reconstitutions with purified mammalian proteins, multicolor TIRF-microscopy, and interaction kinetics measurements, we show that adenomatous polyposis coli (APC) enables kinesin-1- and kinesin-2-based mRNA transport, and that APC is an ideal adaptor for long-range mRNA transport as it forms highly stable complexes with 3'UTR fragments of several neuronal mRNAs (APC-RNPs). The kinesin-1 KIF5A binds and transports several neuronal mRNP components such as FMRP, PURα and mRNA fragments weakly, whereas the transport frequency of the mRNA fragments is significantly increased by APC. APC-RNP-motor complexes can assemble on MTs, generating highly processive mRNA transport events. We further find that end-binding protein 1 (EB1) recruits APC-RNPs to dynamically growing MT ends and APC-RNPs track shrinking MTs, producing MT minus-end-directed RNA motility due to the high dwell times of APC on MTs. Our findings establish APC as a versatile mRNA-kinesin adaptor and a key factor for the assembly and bidirectional movement of neuronal transport mRNPs.


Assuntos
Polipose Adenomatosa do Colo , Cinesinas , Animais , Cinesinas/genética , Proteínas Associadas aos Microtúbulos/metabolismo , RNA Mensageiro/metabolismo , Microtúbulos/metabolismo , Mamíferos/genética
9.
Pediatr Transplant ; 28(4): e14780, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38766999

RESUMO

BACKGROUND: The aims of this study are to report our experience with treosulfan-based conditioning regimens for patients with non-malignant hematologic conditions, correlating clinical outcomes at different time points post-transplant with treosulfan exposure (AUC). METHODS: This study was a single-center observational study investigating overall survival (OS), disease-free survival (DFS), and event-free survival (EFS) end-points post-transplant. The consequences of treosulfan AUC with respect to toxicity, correction of underlying disease, and long-term chimerism were also explored using pharmacokinetic analysis. RESULTS: Forty-six patients received 49 transplants with treosulfan and fludarabine-based conditioning between 2005 and 2023. Twenty-four patients also received thiotepa. Donor chimerism was assessed on either whole blood or sorted cell lines at different time points post-transplant. Thirty-nine patients received treosulfan pharmacokinetic assessment to evaluate cumulative AUC, with five infants receiving real-time assessment to facilitate daily dose adjustment. OS, DFS, and EFS were 87%, 81%, and 69%, respectively. Median follow-up was 32.1 months (range 0.82-160 months) following transplant. Lower EFS was associated with patient age (<1 year; p = .057) and lower cumulative treosulfan dose (<42 g/m2; p = .003). Stable donor chimerism in B-cell, NK-cell, and granulocyte lineages at 1-year post-transplant were more prevalent in patients receiving thiotepa conditioning. Two infants required daily dose adjustment to treosulfan to avoid high AUC. CONCLUSIONS: Excellent clinical outcomes and stable chimerism were observed in this patient series. The addition of thiotepa conferred no significant toxicity and trended toward sustained ongoing donor engraftment. Correlating treosulfan AUC with long-term patient outcomes is required.


Assuntos
Bussulfano , Transplante de Células-Tronco Hematopoéticas , Condicionamento Pré-Transplante , Humanos , Bussulfano/análogos & derivados , Bussulfano/uso terapêutico , Bussulfano/farmacocinética , Bussulfano/administração & dosagem , Condicionamento Pré-Transplante/métodos , Masculino , Transplante de Células-Tronco Hematopoéticas/métodos , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Resultado do Tratamento , Estudos Retrospectivos , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico , Vidarabina/administração & dosagem , Tiotepa/uso terapêutico , Tiotepa/administração & dosagem , Tiotepa/farmacocinética , Intervalo Livre de Doença , Seguimentos , Doenças Hematológicas/terapia , Antineoplásicos Alquilantes/uso terapêutico , Antineoplásicos Alquilantes/farmacocinética , Antineoplásicos Alquilantes/administração & dosagem
10.
Artigo em Inglês | MEDLINE | ID: mdl-38709319

RESUMO

PURPOSE: After the lifting of nonpharmaceutical interventions (NPIs) during the COVID-19 pandemic, clinical observation showed an increase in complications of acute otitis, followed by a rise in the number of mastoidectomies performed. The aim of this study was to record the number of mastoidectomies performed before, during and after the COVID-19 pandemic as an indicator for complications of acute otitis media. METHODS: Data were collected from a tertiary hospital in a university setting, as well as from four major public health insurance companies in Germany. The data of 24,824,763 German citizens during a period from 2014 until 2023 were analyzed. RESULTS: According to the data, during the COVID-19 pandemic, the number of mastoidectomies performed dropped by 54% for children aged 0-6 and by 62% for children aged 7-18. For adults, there were 30% fewer mastoidectomies performed between 2020 and 2022. After the lifting of most NPI's in the season from July 2022 to June 2023, there was a sharp increase in the number of mastoidectomies performed on patients of all ages. CONCLUSIONS: During the COVID-19 pandemic, a decrease in the number of mastoidectomies performed was seen, suggesting a lower incidence of complicated acute otitis, most likely linked to the general decrease of upper airway infections due to NPI's. In contrast, a sharp increase in the incidence of complicated otitis occurred after the hygiene measures were lifted. The current development causes a more frequent performance of mastoidectomies, thus entailing a change in the challenges for everyday clinical practice.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38361075

RESUMO

This study investigated how youth attachment anxiety and avoidance are associated with informant discrepancies of intrafamilial aggression within families where youth have clinically significant mental health challenges (N = 510 youth-parent dyads). Using polynomial regressions, we tested whether youth attachment avoidance and anxiety moderated the absolute magnitude of the association between youth- and parent-reports of aggression toward each other. Furthermore, difference scores were computed to test whether youth attachment was associated with the direction of youths' reports of the frequency of aggression relative to parents (i.e., did youth under- or over-report). Dyads' reports of youth-to-parent aggression were more strongly related at high than low levels of attachment anxiety. Results also revealed that youth attachment anxiety was associated with youth over-reporting of youth-to-parent and parent-to-youth aggression (relative to parents), whereas attachment avoidance was associated with youth over-reporting parent-to-youth aggression (relative to parents). These findings highlight the importance of understanding the source of informant discrepancies in social-emotional development and family functioning.

12.
HNO ; 72(5): 341-349, 2024 May.
Artigo em Alemão | MEDLINE | ID: mdl-38393668

RESUMO

BACKGROUND: In the context of contact restrictions, conventional teaching is currently in need of optimization and expansion. The range of digital teaching formats in student training is very heterogeneous and their effectiveness uncertain. This study aims to investigate the extent to which an electronic ward round can be used as an alternative to the conventional ENT attendance practical course, and whether the use of electronic teaching formats has an influence on the quality of teaching. MATERIALS AND METHODS: Instead of regular attendance practicals, bedside teaching took place once a week in real time as a video stream via tablet. A total of 43 students in the seventh semester (winter semester 2020/2021) were included in the prospective study. Evaluation forms were used to examine the subjective didactic value of different visualization formats for the students. Examination results from previous years were used for comparison. RESULTS: The majority of students reported knowledge gain from the electronic rounds (93.02%) and that they were a good alternative to the traditional attendance clerkship (69.77%). The quality of the video and audio transmission as well as the comprehensibility of the case studies presented were consistently rated as good to very good. The students' examination results tended to be slightly worse in the test group compared to the control students of previous years. CONCLUSION: Integration of innovative interactive visualization options into teaching shows promising prospects as a supplement to conventional face-to-face teaching. The results of this study can contribute to the further expansion of digital teaching. Scaling up this model could be considered especially in countries with limited availability of face-to-face teaching.


Assuntos
Instrução por Computador , Estudantes de Medicina , Alemanha , Humanos , Instrução por Computador/métodos , Feminino , Masculino , Otolaringologia/educação , Interface Usuário-Computador , Currículo , Adulto , Adulto Jovem , Gravação em Vídeo , Ensino , Avaliação Educacional
13.
HNO ; 72(5): 357-366, 2024 May.
Artigo em Alemão | MEDLINE | ID: mdl-38324064

RESUMO

BACKGROUND: Technological change in healthcare and the digital transformation of teaching require innovations in student teaching in medicine. New technologies are needed to enable the delivery and use of diverse teaching and learning formats by educational institutions independent of time and place. The aim of this study is to analyze the effectiveness of different multidimensional formats in student teaching in surgical ENT medical anatomy. MATERIALS AND METHODS: During the summer semester 2022 and winter semester 2022/2023, the digital teaching and learning program was expanded by testing different visualization formats (3D glasses, cardboards, or VR glasses) with students in the context of a highly standardized surgical procedure, namely cochlear implantation. A pre- and post-intervention knowledge assessment was carried out in all groups, followed by an evaluation. RESULTS: Of 183 students, 91 students fully participated in the study. The post-intervention knowledge assessment showed a significant increase in correct answers regardless of visualization format. In a direct comparison, the operating room (OR) group answered correctly significantly more often than the cardboard group (p = 0.0424). The majority of students would like to see 3D teaching as an integral part of the teaching program (87.9%) and more streaming of live surgeries (93.4%). They see the use of the various technologies as a very good addition to conventional surgical teaching (72.5%), as good visualization (89%) increases retention (74.7%) and motivation (81.3%). CONCLUSION: Application and use of new visualization technologies in everyday clinical practice is a promising approach to expanding student training. Mobile, interactive, and personalized technical formats can be adapted to the learning behavior of students. Last but not least, the use of new media influences learning motivation. An expansion of digital teaching and learning formats can be expressly recommended on the basis of this study.


Assuntos
Instrução por Computador , Currículo , Otolaringologia , Otolaringologia/educação , Alemanha , Instrução por Computador/métodos , Humanos , Masculino , Feminino , Estudantes de Medicina , Avaliação Educacional , Anatomia/educação , Adulto Jovem , Ensino , Adulto
14.
Neuroimage ; 271: 119990, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36878456

RESUMO

The processing of reinforcers and punishers is crucial to adapt to an ever changing environment and its dysregulation is prevalent in mental health and substance use disorders. While many human brain measures related to reward have been based on activity in individual brain regions, recent studies indicate that many affective and motivational processes are encoded in distributed systems that span multiple regions. Consequently, decoding these processes using individual regions yields small effect sizes and limited reliability, whereas predictive models based on distributed patterns yield larger effect sizes and excellent reliability. To create such a predictive model for the processes of rewards and losses, termed the Brain Reward Signature (BRS), we trained a model to predict the signed magnitude of monetary rewards on the Monetary Incentive Delay task (MID; N = 39) and achieved a highly significant decoding performance (92% for decoding rewards versus losses). We subsequently demonstrate the generalizability of our signature on another version of the MID in a different sample (92% decoding accuracy; N = 12) and on a gambling task from a large sample (73% decoding accuracy, N = 1084). We further provided preliminary data to characterize the specificity of the signature by illustrating that the signature map generates estimates that significantly differ between rewarding and negative feedback (92% decoding accuracy) but do not differ for conditions that differ in disgust rather than reward in a novel Disgust-Delay Task (N = 39). Finally, we show that passively viewing positive and negatively valenced facial expressions loads positively on our signature, in line with previous studies on morbid curiosity. We thus created a BRS that can accurately predict brain responses to rewards and losses in active decision making tasks, and that possibly relates to information seeking in passive observational tasks.


Assuntos
Encéfalo , Jogo de Azar , Humanos , Reprodutibilidade dos Testes , Encéfalo/fisiologia , Recompensa , Motivação , Jogo de Azar/psicologia , Imageamento por Ressonância Magnética , Mapeamento Encefálico
15.
Int J Cancer ; 153(12): 2068-2081, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37602921

RESUMO

Tumor progression and response to treatment are highly affected by interactions between cancer cells and the tumor microenvironment (TME). Many of the soluble factors and signaling receptors involved in this crosstalk are shed by a disintegrin and metalloproteinases (ADAMs). Upregulation of ADAM15 has been linked to worse survival in cancer patients and a tumor-promoting function both in vitro and in murine cancer models. Although ADAM15 has been involved in cell-cell and cell-extracellular matrix interactions, its role in the crosstalk between cancer cells and the TME in vivo remains unexplored. Therefore, we aimed to understand how ADAM15 regulates the cell composition of the TME and how it affects tumor progression. Here, we showed an upregulation of ADAM15 in tumor tissues from rectal cancer patients. Subcutaneous injection of wildtype and ADAM15-knockout CT26 colon cancer cells in syngeneic mice confirmed the protumorigenic role of ADAM15. Profiling of tumors revealed higher immune cell infiltration and cancer cell apoptosis in the ADAM15-deficient tumors. Specifically, loss of ADAM15 led to a reduced number of granulocytes and higher infiltration of antigen-presenting cells, including dendritic cells and macrophages, as well as more T cells. Using in vitro assays, we confirmed the regulatory effect of ADAM15 on macrophage migration and identified ADAM15-derived CYR61 as a potential molecular mediator of this effect. Based on these findings, we speculate that targeting ADAM15 could increase the infiltration of immune cells in colorectal tumors, which is a prerequisite for effective immunotherapy.


Assuntos
Neoplasias Colorretais , Microambiente Tumoral , Humanos , Camundongos , Animais , Transdução de Sinais , Movimento Celular , Neoplasias Colorretais/genética , Proteínas de Membrana , Proteínas ADAM/genética
16.
Plant Physiol ; 190(1): 211-225, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-35670742

RESUMO

Seeds are highly resilient to the external environment, which allows plants to persist in unpredictable and unfavorable conditions. Some plant species have adopted a bet-hedging strategy to germinate a variable fraction of seeds in any given condition, and this could be explained by population-based threshold models. Here, in the model plant Arabidopsis (Arabidopsis thaliana), we induced secondary dormancy (SD) to address the transcriptional heterogeneity among seeds that leads to binary germination/nongermination outcomes. We developed a single-seed RNA-seq strategy that allowed us to observe a reduction in seed transcriptional heterogeneity as seeds enter stress conditions, followed by an increase during recovery. We identified groups of genes whose expression showed a specific pattern through a time course and used these groups to position the individual seeds along the transcriptional gradient of germination competence. In agreement, transcriptomes of dormancy-deficient seeds (mutant of DELAY OF GERMINATION 1) showed a shift toward higher values of the germination competence index. Interestingly, a significant fraction of genes with variable expression encoded translation-related factors. In summary, interrogating hundreds of single-seed transcriptomes during SD-inducing treatment revealed variability among the transcriptomes that could result from the distribution of population-based sensitivity thresholds. Our results also showed that single-seed RNA-seq is the method of choice for analyzing seed bet-hedging-related phenomena.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Germinação/genética , Dormência de Plantas/genética , Sementes/genética , Sementes/metabolismo , Transcriptoma/genética
17.
J Exp Bot ; 74(6): 2016-2028, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36575905

RESUMO

Beneficial interactions between plant roots and Trichoderma species lead to both local and systemic enhancements of the plant immune system through a mechanism known as priming of defenses. Previously, we have reported a number of genes and proteins that are differentially regulated in distant tissues of maize plants following inoculation with Trichoderma atroviride. To further investigate the mechanisms involved in the systemic activation of plant responses, here we have further evaluated the regulatory aspects of a selected group of genes when priming is triggered in maize plants. Time-course experiments from the beginning of the interaction between T. atroviride and maize roots followed by leaf infection with Colletotrichum graminicola allowed us to identify a gene set regulated by priming in the leaf tissue. In the same experiment, phytohormone measurements revealed a decrease in jasmonic acid concentration while salicylic acid increased at 2 d and 6 d post-inoculation. In addition, chromatin structure and modification assays showed that chromatin was more open in the primed state compared with unprimed control conditions, and this allowed for quicker gene activation in response to pathogen attack. Overall, the results allowed us to gain insights on the interplay between the phytohormones and epigenetic regulatory events in the systemic and long-lasting regulation of maize plant defenses following Trichoderma inoculation.


Assuntos
Trichoderma , Zea mays , Zea mays/genética , Zea mays/metabolismo , Trichoderma/genética , Trichoderma/metabolismo , Ácido Salicílico/metabolismo , Folhas de Planta/metabolismo , Doenças das Plantas/genética , Raízes de Plantas/metabolismo
18.
Mol Psychiatry ; 27(12): 4905-4917, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36127430

RESUMO

Freezing is a conserved defensive behaviour that constitutes a major stress-coping mechanism. Decades of research have demonstrated a role of the amygdala, periaqueductal grey and hypothalamus as core actuators of the control of fear responses, including freezing. However, the role that other modulatory sites provide to this hardwired scaffold is not known. Here, we show that freezing elicited by exposure to electrical foot shocks activates laterodorsal tegmentum (LDTg) GABAergic neurons projecting to the VTA, without altering the excitability of cholinergic and glutamatergic LDTg neurons. Selective chemogenetic silencing of this inhibitory projection, but not other LDTg neuronal subtypes, dampens freezing responses but does not prevent the formation of conditioned fear memories. Conversely, optogenetic-activation of LDTg GABA terminals within the VTA drives freezing responses and elicits bradycardia, a common hallmark of freezing. Notably, this aversive information is subsequently conveyed from the VTA to the amygdala via a discrete GABAergic pathway. Hence, we unveiled a circuit mechanism linking LDTg-VTA-amygdala regions, which holds potential translational relevance for pathological freezing states such as post-traumatic stress disorders, panic attacks and social phobias.


Assuntos
Tonsila do Cerebelo , Substância Cinzenta Periaquedutal , Congelamento , Substância Cinzenta Periaquedutal/metabolismo , Tonsila do Cerebelo/fisiologia , Neurônios GABAérgicos
19.
Br J Clin Pharmacol ; 89(4): 1413-1424, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36369677

RESUMO

AIM: To investigate the pharmacokinetics (PK) of intravenous treosulfan in paediatric patients undergoing haematopoietic stem cell transplantation (HSCT) for a broad range of diseases and to explore the impact of different dosing regimens on treosulfan exposure (area under the concentration-time curve, AUC0→∞ ) through dosing simulations. METHODS: A prospective multicentre PK study was conducted using treosulfan concentration data (n = 423) collected from 53 children (median age 3.5, range 0.2-17.0 years) receiving three daily age-guided doses (10-14 g/m2 ). Population PK modelling was performed using NONMEM software, utilising a stepwise forward selection backward elimination method and likelihood-ratio test for screening covariates to describe PK variability. Monte Carlo simulation was used to generate patient PK data for 10 000 virtual paediatric patients and cumulative AUC0→∞ values were evaluated using age, body surface area (BSA) and model-based dosing regimens, targeting 4800 mg*h/L. RESULTS: Treosulfan concentration data were described using a one-compartment PK model with first-order elimination. Population mean (95% CI) estimates for clearance (CL) and volume of distribution (V) were 16.3 (14.9-18.1) L/h and 41.9 (38.8-45.1) L, respectively. Allometrically scaled body weight was the best covariate descriptor for CL and V, and maturational age further explained variability in CL. Dosing simulations indicated that in young patient groups (<2 years), a model-based dosing regimen more accurately achieved the target AUC0→∞ (58.3%) over the age (42.6%) and BSA-based (51.3%) regimens. CONCLUSION: Treosulfan disposition was described through allometric body weight and maturational age descriptors. Model-informed dosing is recommended for patients under 2 years. Treosulfan PK parameters and AUC0→∞ were not influenced by patient disease.


Assuntos
Bussulfano , Transplante de Células-Tronco Hematopoéticas , Criança , Humanos , Lactente , Pré-Escolar , Adolescente , Estudos Prospectivos , Bussulfano/farmacocinética , Peso Corporal , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
20.
Phys Chem Chem Phys ; 25(44): 30193-30197, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37905423

RESUMO

In this Communication, we study the effect of spurious oscillations in the profiles of energy derivatives with respect to nuclear coordinates calculated with density functional approximations (DFAs) for formaldehyde, pyridine, and furan in their ground and electronic excited states. These spurious oscillations, which can only be removed using extensive integration grids that increase enormously the CPU cost of DFA calculations, are significant in the case of third- and fourth-order energy derivatives of the ground and excited states computed by M06-2X and ωB97X functionals. The errors in question propagate to anharmonic vibronic spectra computed under the Franck-Condon approximation, i.e., positions and intensities of vibronic transitions are affected to a large extent (shifts as significant as hundreds of cm-1 were observed). On the other hand, the LC-BLYP and CAM-B3LYP functionals show a much less pronounced effect due to spurious oscillations. Based on the results presented herein, we recommend either LC-BLYP or CAM-B3LYP with integration grids (250, 974) (or larger) for numerically stable simulations of vibronic spectra including anharmonic effects.

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