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Mitochondrial calcium uptake is crucial to the regulation of eukaryotic Ca2+ homeostasis and is mediated by the mitochondrial calcium uniporter (MCU). While MCU alone can transport Ca2+ in primitive eukaryotes, metazoans require an essential single membrane-spanning auxiliary component called EMRE to form functional channels; however, the molecular mechanism of EMRE regulation remains elusive. Here, we present the cryo-EM structure of the human MCU-EMRE complex, which defines the interactions between MCU and EMRE as well as pinpoints the juxtamembrane loop of MCU and extended linker of EMRE as the crucial elements in the EMRE-dependent gating mechanism among metazoan MCUs. The structure also features the dimerization of two MCU-EMRE complexes along an interface at the N-terminal domain (NTD) of human MCU that is a hotspot for post-translational modifications. Thus, the human MCU-EMRE complex, which constitutes the minimal channel components among metazoans, provides a framework for future mechanistic studies on MCU.
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Canais de Cálcio/metabolismo , Ativação do Canal Iônico/fisiologia , Complexos Multiproteicos/metabolismo , Multimerização Proteica/fisiologia , Canais de Cálcio/genética , Células HEK293 , Humanos , Complexos Multiproteicos/genética , Domínios Proteicos , Estrutura Secundária de ProteínaRESUMO
The epithelium is the main entry point for many viruses, but the processes that protect barrier surfaces against viral infections are incompletely understood. Here we identified interleukin 22 (IL-22) produced by innate lymphoid cell group 3 (ILC3) as an amplifier of signaling via interferon-λ (IFN-λ), a synergism needed to curtail the replication of rotavirus, the leading cause of childhood gastroenteritis. Cooperation between the receptor for IL-22 and the receptor for IFN-λ, both of which were 'preferentially' expressed by intestinal epithelial cells (IECs), was required for optimal activation of the transcription factor STAT1 and expression of interferon-stimulated genes (ISGs). These data suggested that epithelial cells are protected against viral replication by co-option of two evolutionarily related cytokine networks. These data may inform the design of novel immunotherapy for viral infections that are sensitive to interferons.
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Citocinas/imunologia , Expressão Gênica/imunologia , Interleucinas/imunologia , Infecções por Rotavirus/imunologia , Animais , Células CACO-2 , Linhagem Celular , Chlorocebus aethiops , Citocinas/genética , Citocinas/farmacologia , Cães , Sinergismo Farmacológico , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Immunoblotting , Interleucinas/genética , Interleucinas/farmacologia , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Intestinos/virologia , Células Madin Darby de Rim Canino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Receptores de Citocinas/genética , Receptores de Citocinas/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Infecções por Rotavirus/genética , Infecções por Rotavirus/virologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT1/metabolismo , Células Vero , Interleucina 22RESUMO
BACKGROUND: Use of frozen embryo transfer (FET) in in-vitro fertilisation (IVF) has increased. However, the best endometrial preparation protocol for FET cycles is unclear. We compared natural and modified natural cycle strategies with an artificial cycle strategy for endometrial preparation before FET. METHODS: In this randomised, open-label study, we recruited ovulatory women aged 18-45 years at a hospital in Ho Chi Minh City, Viet Nam, who were randomly allocated (1:1:1) to natural, modified natural, or artificial cycle endometrial preparation using a computer-generated random list and block randomisation. The trial was not masked due to the nature of the study interventions. In natural cycles, no oestrogen, progesterone, or human chorionic gonadotropin (hCG) was used. In modified natural cycles, hCG was used to trigger ovulation. In artificial cycles, oral oestradiol valerate (8 mg/day from day 2-4 of menstruation) and vaginal progesterone (800 mg/day starting when endometrial thickness was ≥7 mm) were used. Embryos were vitrified, and then one or two day-3 embryos or one day-5 embryo were warmed and transferred under ultrasound guidance. If the first FET cycle was cancelled, subsequent cycles were performed with artificial endometrial preparation. The primary endpoint was livebirth after one FET. This trial is registered at ClinicalTrials.gov, NCT04804020. FINDINGS: Between March 22, 2021, and March 14, 2023, 4779 women were screened and 1428 were randomly assigned (476 to each group). 99 first FET cycles were cancelled in each of the natural and modified cycle groups, versus none in the artificial cycle group. The livebirth rate after one FET was 174 (37%) of 476 in the natural cycle strategy group, 159 (33%) of 476 in the modified natural cycle strategy group, and 162 (34%) of 476 in the artificial cycle strategy group (relative risk 1·07 [95% CI 0·87-1·33] for natural vs artificial cycle strategy, and 0·98 [0·79-1·22] for modified natural vs artificial cycle strategy). Maternal and neonatal outcomes did not differ significantly between groups, as the power to detect small differences was low. INTERPRETATION: Although the livebirth rate was similar after natural, modified natural, and artificial cycle endometrial preparation strategies in ovulatory women undergoing FET IVF, no definitive conclusions can be made regarding the comparative safety of the three approaches. FUNDING: None.
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Criopreservação , Transferência Embrionária , Endométrio , Nascido Vivo , Progesterona , Humanos , Feminino , Adulto , Transferência Embrionária/métodos , Gravidez , Vietnã , Progesterona/administração & dosagem , Adulto Jovem , Estradiol/administração & dosagem , Ovulação/efeitos dos fármacos , Adolescente , Fertilização in vitro/métodos , Indução da Ovulação/métodos , Pessoa de Meia-Idade , Taxa de Gravidez , Gonadotropina Coriônica/administração & dosagemRESUMO
Oncogenes are commonly amplified on particles of extrachromosomal DNA (ecDNA) in cancer1,2, but our understanding of the structure of ecDNA and its effect on gene regulation is limited. Here, by integrating ultrastructural imaging, long-range optical mapping and computational analysis of whole-genome sequencing, we demonstrate the structure of circular ecDNA. Pan-cancer analyses reveal that oncogenes encoded on ecDNA are among the most highly expressed genes in the transcriptome of the tumours, linking increased copy number with high transcription levels. Quantitative assessment of the chromatin state reveals that although ecDNA is packaged into chromatin with intact domain structure, it lacks higher-order compaction that is typical of chromosomes and displays significantly enhanced chromatin accessibility. Furthermore, ecDNA is shown to have a significantly greater number of ultra-long-range interactions with active chromatin, which provides insight into how the structure of circular ecDNA affects oncogene function, and connects ecDNA biology with modern cancer genomics and epigenetics.
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Cromatina/genética , DNA Circular/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias/genética , Oncogenes/genética , Linhagem Celular Tumoral , Cromatina/química , DNA Circular/genética , Humanos , Microscopia Eletrônica de Varredura , Neoplasias/fisiopatologiaRESUMO
Electrical neuron stimulation holds promise for treating chronic neurological disorders, including spinal cord injury, epilepsy, and Parkinson's disease. The implementation of ultrathin, flexible electrodes that can offer noninvasive attachment to soft neural tissues is a breakthrough for timely, continuous, programable, and spatial stimulations. With strict flexibility requirements in neural implanted stimulations, the use of conventional thick and bulky packages is no longer applicable, posing major technical issues such as short device lifetime and long-term stability. We introduce herein a concept of long-lived flexible neural electrodes using silicon carbide (SiC) nanomembranes as a faradic interface and thermal oxide thin films as an electrical barrier layer. The SiC nanomembranes were developed using a chemical vapor deposition (CVD) process at the wafer level, and thermal oxide was grown using a high-quality wet oxidation technique. The proposed material developments are highly scalable and compatible with MEMS technologies, facilitating the mass production of long-lived implanted bioelectrodes. Our experimental results showed excellent stability of the SiC/silicon dioxide (SiO2) bioelectronic system that can potentially last for several decades with well-maintained electronic properties in biofluid environments. We demonstrated the capability of the proposed material system for peripheral nerve stimulation in an animal model, showing muscle contraction responses comparable to those of a standard non-implanted nerve stimulation device. The design concept, scalable fabrication approach, and multimodal functionalities of SiC/SiO2 flexible electronics offer an exciting possibility for fundamental neuroscience studies, as well as for neural stimulation-based therapies.
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Terapia por Estimulação Elétrica , Neuroestimuladores Implantáveis , Nanoestruturas , Semicondutores , Compostos Inorgânicos de Carbono/química , Terapia por Estimulação Elétrica/instrumentação , Membranas Artificiais , Compostos de Silício/química , Dióxido de Silício/químicaRESUMO
We conducted this systematic review and meta-analysis to clarify the trend of precocious puberty (PP) incidence after the COVID-19 outbreak and explore potential contributing factors, such as age at presentation and body mass index standard deviation score (BMI SDS). Children visiting pediatric endocrinology clinics for the first time for suspected PP were included. We searched databases until February 28, 2023 for studies reporting various indicators of PP incidence before and during the pandemic. Total numbers of events and observations were recorded. A meta-analysis was performed to compare the odds of PP, BMI SDS, and age at presentation between the two periods. The dose-response relationships between time points (by number of years away from the pandemic) and PP risk were explored. In summary, a total of 32 studies including 24,200 participants were recruited. COVID-19 pandemic was associated with the increasing odds of PP among children referred for suspicious condition (OR 1.96; 95% CI 1.56-2.47; I2 = 54%; P < 0.001). Sensitivity analysis confirmed the robustness of the findings. BMI SDS did not vary between the two periods, while age at presentation was lower following the pandemic. PP incidence increased more rapidly during the pandemic period than during the prepandemic period.
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Microfluidic particle and cell manipulation techniques possess many potentials for biomedicine and healthcare. Many techniques have been developed based on active (e.g., electrical, magnetic, acoustic, and thermal) force fields and passive hydrodynamic forces (e.g., inertial and elastic lift forces). However, techniques based on a single active or passive manipulating physics cannot always meet the demands, and combining multiple physics becomes a promising strategy to promote technique flexibility and versatility. In this work, we explored the physical coupling of magnetophoresis with the elastic and inertial (i.e., elasto-inertial) lift forces for the manipulation of microparticles. Particle lateral migration was studied in a coflowing configuration of viscoelastic ferrofluid/water (sample/sheath). The particles were suspended in the viscoelastic ferrofluid and confined near the channel sidewall by a sheath flow. The coordination of magnetophoresis and elasto-inertial lift forces promoted the cross-stream migration of particles. Besides, we investigated the effect of the flow rate ratio and total flow rate on the migration of particles. Furthermore, we also investigated the effects of fluid elasticity in sample and sheath flows on particle migration using different combinations of sample and sheath flows, including Newtonian ferrofluid/water, Newtonian ferrofluid/viscoelastic fluid, and viscoelastic ferrofluid/viscoelastic coflows. Experimental results demonstrated and ascertained the promoted particle lateral migration in the PEO-based ferrofluid/water coflow. Finally, we demonstrate the proof-of-concept application of the physical coupling strategy for cell cross-stream migration and solution exchange. We envisage that this novel multiphysical coupling scheme has great potential for the flexible and versatile manipulation of microparticles and cells.
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INTRODUCTION: Eosinophilic esophagitis (EoE) is associated with atopy; however, recent studies have identified an association with food-specific immunoglobulin G 4 (FS-IgG 4 ) rather than immunoglobulin E antibodies. This study aimed to evaluate the role of serum FS-IgG 4 in guiding an elimination diet and its outcomes. METHODS: Patients with and without EoE were enrolled in a prospective, controlled, single tertiary center trial. Serum FS-IgG 4 titers, esophageal eosinophil counts, and dysphagia symptom questionnaire scores were assessed, and participants with elevated FS-IgG 4 (ImmunoCAP, cutoff of 10 mgA/L) commenced 6-week targeted elimination diet. Repeat serum FS-IgG 4 and endoscopic and histologic examination were performed at 6-week follow-up. RESULTS: Twenty-two patients with active EoE and 13 controls were recruited. Serum FS-IgG 4 to milk, wheat, soy, eggs, and nuts was significantly higher in EoE ( P = 0.0002, P = 0.002, P = 0.003, P = 0.012, and P < 0.001, respectively). Elevated serum FS-IgG 4 to 1 or more food groups (median 2) was identified in 21/22 (95.4%) patients with EoE; 20/21 underwent 6-week dietary elimination. Median reductions in dysphagia symptom questionnaire score and EoE endoscopic reference score after elimination were 8 ( P = 0.0007) and 1 ( P = 0.002), respectively. Nine (45%) patients had histological remission (<15 eosinophils per high-power field). Fall in median esophageal eosinophil count was not statistically significant (50 vs 23; P = 0.068). Serum FS-IgG 4 did not decline by 6-week follow-up. DISCUSSION: Serum FS-IgG 4 to milk, wheat, soy, egg, and nuts was present at higher levels in EoE, with targeted elimination resulting in 45% histologic remission rate. Serum FS-IgG 4 has potential as a noninvasive biomarker in EoE. When successful, FS-IgG 4 -led elimination diet can negate need for medications and be viewed more favorably by patients because of its smaller endoscopic burden compared with empirical elimination diets.
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Esofagite Eosinofílica , Imunoglobulina G , Humanos , Esofagite Eosinofílica/dietoterapia , Esofagite Eosinofílica/imunologia , Esofagite Eosinofílica/sangue , Feminino , Masculino , Imunoglobulina G/sangue , Adulto , Estudos Prospectivos , Pessoa de Meia-Idade , Hipersensibilidade Alimentar/dietoterapia , Hipersensibilidade Alimentar/complicações , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/sangue , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/dietoterapia , Esofagoscopia , Eosinófilos/imunologia , Adulto Jovem , Dieta de EliminaçãoRESUMO
Understanding the growth of mesoporous crystalline materials, such as mesoporous metals, on different substrates can provide valuable insights into the crystal growth dynamics and the redox reactions that influence their electrochemical sensing performance. Herein, it is demonstrated how the amorphous nature of the glass substrate can suppress the typical <111> oriented growth in mesoporous Au (mAu) films. The suppressed <111> growth is manifested as an accumulation of strain, leading to the generation of abundant surface defects, which are beneficial for enhancing the electrochemical activity. The fine structuring attained enables dramatically accelerated diffusion and enhances the electrochemical sensing performance for disease-specific biomolecules. As a proof-of-concept, the as-fabricated glass-grown mAu film demonstrates high sensitivity in electrochemical detection of SARS-CoV-2-specific RNA with a limit of detection (LoD) as low as 1 attomolar (aM).
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Ouro/química , Técnicas Biossensoriais/métodos , Porosidade , Técnicas Eletroquímicas/métodos , Catálise , SARS-CoV-2/isolamento & purificação , Limite de Detecção , RNA Viral , COVID-19/virologia , COVID-19/diagnósticoRESUMO
INTRODUCTION: The current obesity crisis has resulted in many people with excess adipose tissue suffering from chronic inflammation. This inflammation is largely due to the release of cytokines and chemokines from visceral fat. The aim of this study was to identify potential anti-inflammatory agents that might alleviate obesity-induced chronic inflammation. METHODS: To identify agents that might alleviate this obesity-induced chronic inflammation we have developed a simple protocol for incubating intact pieces of human visceral adipose tissue in 35 mm tissue culture plates, in the presence of low-dose lipopolysaccharide (LPS) and co-incubating these samples with potential anti-inflammatory agents. RNA-Seq analysis was performed to identify enriched gene expression signatures among the most significantly differentially expressed genes. RESULTS: From this screen, we have identified the short-chain fatty acid (SCFA) sodium butyrate and its triacylglyceride form, tributyrin, as effective agents, significantly reducing the production of LPS-induced inflammatory cytokines and chemokines from all adipose tissue samples tested. As well, these agents appear to be non-toxic at the concentrations tested. RNA-Seq analysis has revealed that IL36γ is one of the most upregulated genes in response to LPS and one of the most downregulated when sodium butyrate is added to human fat samples stimulated with LPS. IL-36γ ELISAs confirmed this holds true at the protein level as well. CONCLUSIONS: These studies suggest that the short-chain fatty acid, sodium butyrate, and its triacylglyceride form, tributyrin, might alleviate the chronic inflammation that is associated with many individuals with obesity.
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This study investigated an association between the cytochrome P450 (CYP) 2C8*3 polymorphism with asthma symptom control in children and changes in lipid metabolism and pro-inflammatory signaling by human bronchial epithelial cells (HBECs) treated with cigarette smoke condensate (CSC). CYP genes are inherently variable in sequence, and while such variations are known to produce clinically relevant effects on drug pharmacokinetics and pharmacodynamics, the effects on endogenous substrate metabolism and associated physiologic processes are less understood. In this study, CYP2C8*3 was associated with improved asthma symptom control among children: Mean asthma control scores were 3.68 (n = 207) for patients with one or more copies of the CYP2C8*3 allele versus 4.42 (n = 965) for CYP2C8*1/*1 (P = 0.0133). In vitro, CYP2C8*3 was associated with an increase in montelukast 36-hydroxylation and a decrease in linoleic acid metabolism despite lower mRNA and protein expression. Additionally, CYP2C8*3 was associated with reduced mRNA expression of interleukin-6 (IL-6) and C-X-C motif chemokine ligand 8 (CXCL-8) by HBECs in response to CSC, which was replicated using the soluble epoxide hydrolase inhibitor, 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid. Interestingly, 9(10)- and 12(13)- dihydroxyoctadecenoic acid, the hydrolyzed metabolites of 9(10)- and 12(13)- epoxyoctadecenoic acid, increased the expression of IL-6 and CXCL-8 mRNA by HBECs. This study reveals previously undocumented effects of the CYP2C8*3 variant on the response of HBECs to exogenous stimuli. SIGNIFICANCE STATEMENT: These findings suggest a role for CYP2C8 in regulating the epoxyoctadecenoic acid:dihydroxyoctadecenoic acid ratio leading to a change in cellular inflammatory responses elicited by environmental stimuli that exacerbate asthma.
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Asma , Brônquios , Citocromo P-450 CYP2C8 , Células Epiteliais , Humanos , Asma/tratamento farmacológico , Asma/genética , Asma/metabolismo , Citocromo P-450 CYP2C8/genética , Citocromo P-450 CYP2C8/metabolismo , Criança , Masculino , Feminino , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Adolescente , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Inflamação/genética , Inflamação/metabolismo , Células Cultivadas , Quinolinas/farmacologia , Polimorfismo de Nucleotídeo Único , Acetatos , Ciclopropanos , SulfetosRESUMO
STUDY QUESTION: In non-male factor infertile couples, are there any differences in the developmental outcomes between children born through ICSI and conventional IVF (cIVF)? SUMMARY ANSWER: In this preliminary study, ICSI and cIVF seem to have a comparable effect on developmental outcomes after 12 months in children born to non-male factor infertile couples. WHAT IS KNOWN ALREADY: ICSI, an invasive technique, has raised concerns about potential developmental abnormalities in children. Limited data are available regarding the developmental outcomes of ICSI-conceived infants born to non-male factor infertile couples. STUDY DESIGN, SIZE, DURATION: This prospective cohort study involved a follow-up of all children aged 12 months or older who were born from pregnancies resulting from either ICSI or cIVF as part of a previous randomized controlled trial (RCT) (NCT03428919). PARTICIPANTS/MATERIALS, SETTING, METHODS: In the original RCT, 1064 women were randomly assigned to the ICSI or cIVF groups (532 women for each group). Follow-up was conducted with 155 couples (195 children) in the ICSI group and 141 couples (185 children) in the cIVF group. The Vietnamese version of the Ages & Stages Third Edition Questionnaires (ASQ-3) and the Development Red Flags questionnaires were completed by the participants. A total of 141 (90.1%) women (177 children) in the ICSI group and 113 (80.1%) women (145 children) in the cIVF group returned fully completed questionnaires. The primary outcomes were the developmental outcomes based on responses to the ASQ-3 and the Red Flags questionnaire. MAIN RESULTS AND THE ROLE OF CHANCE: The mean age of children at follow-up was 19.5 ± 5.0 months in the ICSI group and 19.3 ± 5.5 months in the cIVF group. The mean height and weight of children in both groups were similar. The overall proportion of children with any abnormal ASQ-3 score did not differ significantly between the ICSI and cIVF groups (16.9% vs 13.1%, P = 0.34). The proportion of children with Red Flag signs was also comparable between the two groups (6.2% vs 9.2%, P = 0.36, ICSI vs cIVF, respectively). LIMITATIONS, REASONS FOR CAUTION: Despite a reasonably high follow-up response rate, there is a potential risk of sampling bias, and overall, the number of children with developmental abnormalities was very small. The study relied solely on questionnaires as screening tools, rather than incorporating additional behavioral observations or physical developmental tests; this may have affected the statistical power and the significance of between-group comparisons. WIDER IMPLICATIONS OF THE FINDINGS: The current findings contribute to the existing evidence and support the comparative safety of ICSI and cIVF regarding early childhood development. However, more extensive and prolonged follow-up data for these children are needed to draw definitive conclusions. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this study, and no authors reported conflicting interests. TRIAL REGISTRATION NUMBER: NCT04866524 (clinicaltrials.gov).
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We report the fabrication and characterisation of magnetic liquid beads with a solid magnetic shell and liquid core using microfluidic techniques. The liquid beads consist of a fluorinated oil core and a polymer shell with magnetite particles. The beads are generated in a flow-focusing polydimethylsiloxane (PDMS) device and cured by photo polymerisation. We investigated the response of the liquid beads to an external magnetic field by characterising their motion towards a permanent magnet. Magnetic sorting of liquid beads in a channel was achieved with 90% efficiency. The results show that the liquid beads can be controlled magnetically and have potential applications in digital microfluidics including nucleic acid amplification, drug delivery, cell culture, sensing, and tissue engineering. The present paper also discusses the magnetophoretic behaviour of the liquid bead by varying its mass and magnetite concentration in the shell. We also demonstrated the two-dimensional self-assembly of magnetic liquid beads for potential use in digital polymerase chain reaction and digital loop mediated isothermal amplification.
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Dimetilpolisiloxanos , Dimetilpolisiloxanos/química , Técnicas Analíticas Microfluídicas/instrumentação , Campos Magnéticos , MicroesferasRESUMO
Telemedicine is being applied in assisted reproduction technology (ART) to provide remote consultations, monitoring and support for patients. This study aimed to evaluate the potential advantages of telemedicine in ART treatment in the form of virtual consultations. Studies in which patients were using telemedicine during ART treatment were identified from four scientific databases (PudMed, EMBASE, Scopus, Web of Science). The success of fertility treatments was compared between telemedicine and in-office care, and patient satisfaction with ART through telemedicine was assessed. Eleven studies, comprising 4697 patients, were identified. Quality assessment (Joanna Briggs Institute Critical Appraisal and revised Cochrane risk-of-bias tools) revealed an acceptable risk of bias for both randomized controlled trials and observational studies. Using a fixed-effects model, telemedicine was comparable to in-person care regarding the pregnancy rate achieved (odds ratio 1.02, 95% confidence intervals 0.83-1.26, Pâ¯=â¯0.83). A Q-test suggested that all the included studies were homogeneous. Patients who received telemedicine during fertility treatment reported a high level of satisfaction (91%, 95% confidence intervals 80-96%). Egger's test confirmed that no publication bias was found. Telemedicine could serve as a complementary tool during fertility treatment to facilitate patients' satisfaction and overcome some practical problems without compromising treatment outcomes. Future studies should continue exploring the potential applications of telemedicine in assisted reproduction.
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Satisfação do Paciente , Técnicas de Reprodução Assistida , Telemedicina , Humanos , Feminino , Gravidez , Taxa de GravidezRESUMO
Escherichia coli expresses surface appendages including fimbriae, flagella, and curli, at various levels in response to environmental conditions and external stimuli. Previous studies have revealed an interplay between expression of fimbriae and flagella in several E. coli strains, but how this regulation between fimbrial and flagellar expression affects adhesion to interfaces is incompletely understood. Here, we investigate how the concurrent expression of fimbriae and flagella by engineered strains of E. coli MG1655 affects their adhesion at liquid-solid and liquid-liquid interfaces. We tune fimbrial and flagellar expression on the cell surface through plasmid-based inducible expression of the fim operon and fliC-flhDC genes. We show that increased fimbrial expression increases interfacial adhesion as well as bacteria-driven actuation of micron-sized objects. Co-expression of flagella in fimbriated bacteria, however, does not greatly affect either of these properties. Together, these results suggest that interfacial adhesion as well as motion actuated by adherent bacteria can be altered by controlling the expression of surface appendages.
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Chemotherapy is used as neoadjuvant therapy for all subgroups of breast cancer, including ER-positive, and HER2-negative cases. However, studies have suggested that using aromatase inhibitors combined with CDK4/6-inhibitors might be an appropriate alternative in selected patients. Thus, the NEOLETRIB trial evaluates the response of ER-positive, HER2-negative luminal A/B breast cancer to the combination of letrozole and ribociclib in the neoadjuvant setting. Comprehensive molecular biology procedures, including sequential single-cell RNA-sequencing of tumor biopsies, are performed during 6 months of treatment with extensive biobanking of blood samples, tumor biopsies and gut microbiome specimens. Our findings will hopefully contribute to an improved selection of patients who may benefit from this drug combination and give new insights into the intra-tumoral changes during this treatment.Trial registration number: NCT05163106 (ClinicalTrials.gov).
[Box: see text].
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The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel localized to the inner mitochondrial membrane. Here, we describe the structure of an MCU orthologue from the fungus Neosartorya fischeri (NfMCU) determined to 3.8 Å resolution by phase-plate cryo-electron microscopy. The channel is a homotetramer with two-fold symmetry in its amino-terminal domain (NTD) that adopts a similar structure to that of human MCU. The NTD assembles as a dimer of dimers to form a tetrameric ring that connects to the transmembrane domain through an elongated coiled-coil domain. The ion-conducting pore domain maintains four-fold symmetry, with the selectivity filter positioned at the start of the pore-forming TM2 helix. The aspartate and glutamate sidechains of the conserved DIME motif are oriented towards the central axis and separated by one helical turn. The structure of NfMCU offers insights into channel assembly, selective calcium permeation, and inhibitor binding.
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Canais de Cálcio/química , Canais de Cálcio/ultraestrutura , Microscopia Crioeletrônica , Neosartorya/química , Sítios de Ligação , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Humanos , Ativação do Canal Iônico/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Modelos Moleculares , Domínios Proteicos , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Compostos de Rutênio/farmacologia , SolubilidadeRESUMO
In this Article, ref. 15 has been replaced and references 32 to 50 have been renumbered online.
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Immune checkpoint blockade therapy has been successful in treating some types of cancer but has not shown clinical benefits for treating leukaemia1. This result suggests that leukaemia uses unique mechanisms to evade this therapy. Certain immune inhibitory receptors that are expressed by normal immune cells are also present on leukaemia cells. Whether these receptors can initiate immune-related primary signalling in tumour cells remains unknown. Here we use mouse models and human cells to show that LILRB4, an immunoreceptor tyrosine-based inhibition motif-containing receptor and a marker of monocytic leukaemia, supports tumour cell infiltration into tissues and suppresses T cell activity via a signalling pathway that involves APOE, LILRB4, SHP-2, uPAR and ARG1 in acute myeloid leukaemia (AML) cells. Deletion of LILRB4 or the use of antibodies to block LILRB4 signalling impeded AML development. Thus, LILRB4 orchestrates tumour invasion pathways in monocytic leukaemia cells by creating an immunosuppressive microenvironment. LILRB4 represents a compelling target for the treatment of monocytic AML.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Evasão Tumoral/imunologia , Animais , Apolipoproteínas E/metabolismo , Arginase/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Movimento Celular , Proliferação de Células , Feminino , Humanos , Tolerância Imunológica/imunologia , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Masculino , Glicoproteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Receptores Imunológicos , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Utilization of point-of-care 3-dimensional printing (3DP) has decreased length of surgery in facial trauma. Little is known regarding 3DP's impact on length of surgery in orbital fracture. PURPOSE: The purpose of this study was to compare length of surgery between 3DP/preadapted (3DPPA) orbital plates and intraoperative adapted plates (IOAP) for orbital fracture reconstruction. STUDY DESIGN, SETTING, SAMPLE: This was a prospective, non-blinded, randomized clinical study of consecutive subjects with orbital fractures presented to Grady Memorial Hospital in Atlanta, Georgia, between January 2018 and June 2021. Subjects ≥ 18 years, unilateral fracture, no previous orbital surgery, and/or congenital craniofacial anomaly were included. We excluded subjects <18 years and bilateral fractures. PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: Primary predictor variable was the treatment approach. Randomization software was used, and subjects were randomized to 3DPPA or IOAP groups. MAIN OUTCOME VARIABLE(S): Primary outcome variable was length of surgery in minutes. Secondary outcomes were the time required for plate insertion and fixation in minutes, operating room (OR) charges, and orbital volume (OV) calculation. COVARIATES: Age, sex, race, etiology, laterality, location, dimension, indication for surgery, postoperative enophthalmos, and diplopia. ANALYSES: Univariate and bivariate analyses were calculated. Statistical significance was P < .05. RESULTS: Twenty-five subjects met the inclusion criteria. Mean ages in 3DPPA and conventional IOAP groups were 41.5 (±9) and 38.2 (±10, P = .31), respectively. The mean length of surgery was 32.6 (±13.7) in 3DPPA and 53.3 (±12.8, P < .001) in conventional IOAP. The mean time required for plate insertion and fixation was 15.8n (±14.4) in 3DPPA and 41.4 (±9.4, P < .001) in conventional IOAP. The mean OR charges were $1,072.5 (±524.6) in 3DPPA and $1,757.3 (±422.6, P ≤ 0.001) in conventional IOAP. The mean calculated OV of uninjured and reconstructed orbit for the 3DPPA was 23.5 (±3.2)cm3 and 23 (±3.5, P = .37)cm3, respectively. The mean calculated OV of uninjured and reconstructed orbit for conventional IOAP was 28.6 (±3.6)cm3 and 22.8 (±2.6, P < .001)cm3, respectively. CONCLUSION AND RELEVANCE: Using 3DP to produce a model that enables preoperative plate bending/adaptation reduces the length of surgery, decreases OR charges, and results in predictable OV.