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1.
Nat Immunol ; 17(6): 704-11, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27064374

RESUMO

The asymmetric partitioning of fate-determining proteins has been shown to contribute to the generation of CD8(+) effector and memory T cell precursors. Here we demonstrate the asymmetric partitioning of mTORC1 activity after the activation of naive CD8(+) T cells. This results in the generation of two daughter T cells, one of which shows increased mTORC1 activity, increased glycolytic activity and increased expression of effector molecules. The other daughter T cell has relatively low mTORC1 activity and increased lipid metabolism, expresses increased amounts of anti-apoptotic molecules and subsequently displays enhanced long-term survival. Mechanistically, we demonstrate a link between T cell antigen receptor (TCR)-induced asymmetric expression of amino acid transporters and RagC-mediated translocation of mTOR to the lysosomes. Overall, our data provide important insight into how mTORC1-mediated metabolic reprogramming affects the fate decisions of T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Divisão Celular/imunologia , Lisossomos/metabolismo , Complexos Multiproteicos/metabolismo , Células Precursoras de Linfócitos T/imunologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Feminino , Glicólise , Memória Imunológica , Metabolismo dos Lipídeos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transporte Proteico , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
2.
Nat Immunol ; 15(5): 457-64, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24705297

RESUMO

SGK1 is an AGC kinase that regulates the expression of membrane sodium channels in renal tubular cells in a manner dependent on the metabolic checkpoint kinase complex mTORC2. We hypothesized that SGK1 might represent an additional mTORC2-dependent regulator of the differentiation and function of T cells. Here we found that after activation by mTORC2, SGK1 promoted T helper type 2 (TH2) differentiation by negatively regulating degradation of the transcription factor JunB mediated by the E3 ligase Nedd4-2. Simultaneously, SGK1 repressed the production of interferon-γ (IFN-γ) by controlling expression of the long isoform of the transcription factor TCF-1. Consistent with those findings, mice with selective deletion of SGK1 in T cells were resistant to experimentally induced asthma, generated substantial IFN-γ in response to viral infection and more readily rejected tumors.


Assuntos
Asma/imunologia , Proteínas Imediatamente Precoces/metabolismo , Melanoma Experimental/imunologia , Complexos Multiproteicos/imunologia , Infecções por Poxviridae/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Serina-Treonina Quinases TOR/imunologia , Células Th1/imunologia , Células Th2/imunologia , Vaccinia virus/imunologia , Imunidade Adaptativa/genética , Animais , Diferenciação Celular/genética , Células Cultivadas , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Regulação da Expressão Gênica/genética , Fator 1-alfa Nuclear de Hepatócito , Proteínas Imediatamente Precoces/genética , Interferon gama/genética , Interferon gama/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ubiquitina-Proteína Ligases Nedd4 , Proteínas Serina-Treonina Quinases/genética , Fator 1 de Transcrição de Linfócitos T/genética , Fator 1 de Transcrição de Linfócitos T/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Carga Tumoral/genética , Ubiquitina-Proteína Ligases/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(1): e2211442120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574693

RESUMO

In this study, an aqueous nonlinear synaptic element showing plasticity behavior is developed, which is based on the chemical processes in an ionic diode. The device is simple, fully ionic, and easily configurable, requiring only two terminals-for input and output-similar to biological synapses. The key processes realizing the plasticity features are chemical precipitation and dissolution, which occur at forward- or reverse-biased ionic diode junctions in appropriate reservoir electrolytes. Given that the precipitate acts as a physical barrier in the circuit, the above processes change the diode conductivity, which can be interpreted as adjusting "synaptic weight" of the system. By varying the operating conditions, we first demonstrate the four types of plasticity that can be found in biological system: long-term potentiation/depression and short-term potentiation/depression. The plasticity of the proposed iontronic device has characteristics similar to those of neural synapses. To demonstrate its potential use in comparatively complex information processing, we develop a precipitation-based iontronic synapse (PIS) capable of both potentiation and depression. Finally, we show that the postsynaptic signals from the multiple excitatory or inhibitory PISs can be integrated into the total "dendritic" current, which is a function of time and input history, as in actual hippocampal neural circuits.


Assuntos
Hidrogéis , Plasticidade Neuronal , Solubilidade , Potenciação de Longa Duração , Sinapses , Íons , Precipitação Química
4.
Curr Issues Mol Biol ; 46(1): 741-752, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38248350

RESUMO

Smoking cigarettes is known to lower the risk of preeclampsia. The objective of this study is to evaluate the effect of smoking on the expression of soluble FMS-like tyrosine kinase-1 (sFlt-1), vascular endothelial growth factor (VEGF), and endoglin (sEng)-1 and the role of the aryl hydrocarbon receptor (AhR) in pregnant mice. We developed a smoking mouse model using a gas-filling system. One or two cigarettes per day were exposed to each of the five pregnant mice for five days a week throughout pregnancy. AhR agonist and antagonist were injected. Serum levels and expression in the placenta of sFlt-1, VEGF, and sEng-1 were analyzed and compared among the cigarette smoke and no-exposure groups after delivery. Compared to the no-smoke exposure group, the serum level of sFlt-1 was significantly decreased in the two-cigarette-exposed group (p < 0.001). When the AhR antagonist was added to the two-cigarette-exposed group, sFlt-1 levels were significantly increased compared to the two-cigarette group (p = 0.002). The levels of sFlt-1 in the AhR antagonist group did not change regardless of two-cigarette exposure (p = 0.064). With the AhR agonist, sFlt-1 decreased significantly compared to the control (p = 0.001) and AhR antagonist group (p = 0.002). The sFlt-1 level was significantly decreased after the injection of the AhR agonist compared to the control group (p = 0.001). Serum levels of VEGF were significantly decreased in the one-cigarette-exposed group compared to the control group; however, there was no difference between the control and the two-cigarette-exposed groups. The placental expression of sFlt-1, VEGF, and sEng were inconsistent. This study offers insights into the potential role of AhR on antiangiogenic sFlt-1 associated with preeclampsia. It may support the invention of a new treatment strategy for preeclampsia using AhR activation.

5.
Opt Express ; 32(8): 13048-13064, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859285

RESUMO

We propose and demonstrate an angularly offset multiline (AOML) dispersive silicon nitride optical phased array (OPA) that enables efficient line beam scanning with an expanded field of view (FOV) and plateau envelope. The suggested AOML OPA incorporates multiline OPA units, which were seamlessly integrated with a 45° angular offset through a thermo-optic switch based on a multimode interference coupler, resulting in a wide FOV that combines three consecutive scanning ranges. Simultaneously, a periodic diffraction envelope rendered by the multiline OPA units contributes to reduced peak intensity fluctuation of the main lobe across the large FOV. An expedient polishing enabling the angled facet was diligently accomplished through the implementation of oblique polishing techniques applied to the 90° angle of the chip. For each dispersive OPA unit, we engineered an array of delay lines with progressively adjustable delay lengths, enabling a passive wavelength-tunable beam scanning. Experimental validation of the proposed OPA revealed efficient beam scanning, achieved by wavelength tuning from 1530 to 1600 nm and seamless switching between multiline OPAs, yielding an FOV of 152° with a main lobe intensity fluctuation of 2.8 dB. The measured efficiency of dispersive scanning was estimated at 0.97°/nm, as intended.

6.
Psychol Sci ; 35(4): 345-357, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38407962

RESUMO

A major challenge in assessing psychological constructs such as impulsivity is the weak correlation between self-report and behavioral task measures that are supposed to assess the same construct. To address this issue, we developed a real-time driving task called the "highway task," in which participants often exhibit impulsive behaviors mirroring real-life impulsive traits captured by self-report questionnaires. Here, we show that a self-report measure of impulsivity is highly correlated with performance in the highway task but not with traditional behavioral task measures of impulsivity (47 adults aged 18-33 years). By integrating deep neural networks with an inverse reinforcement learning (IRL) algorithm, we inferred dynamic changes of subjective rewards during the highway task. The results indicated that impulsive participants attribute high subjective rewards to irrational or risky situations. Overall, our results suggest that using real-time tasks combined with IRL can help reconcile the discrepancy between self-report and behavioral task measures of psychological constructs.


Assuntos
Comportamento Impulsivo , Reforço Psicológico , Adulto , Humanos , Autorrelato , Inquéritos e Questionários , Aprendizagem
7.
J Immunol ; 209(12): 2287-2291, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36469844

RESUMO

The mechanistic target of rapamycin is an essential regulator of T cell metabolism and differentiation. In this study, we demonstrate that serum- and glucocorticoid-regulated kinase 1 (SGK1), a downstream node of mechanistic target of rapamycin complex 2 signaling, represses memory CD8+ T cell differentiation. During acute infections, murine SGK1-deficient CD8+ T cells adopt an early memory precursor phenotype leading to more long-lived memory T cells. Thus, SGK1-deficient CD8+ T cells demonstrate an enhanced recall capacity in response to reinfection and can readily reject tumors. Mechanistically, activation of SGK1-deficient CD8+ T cells results in decreased Foxo1 phosphorylation and increased nuclear translocation of Foxo1 to promote early memory development. Overall, SGK1 might prove to be a powerful target for enhancing the efficacy of vaccines and tumor immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Alvo Mecanístico do Complexo 2 de Rapamicina , Células T de Memória , Proteínas Serina-Treonina Quinases , Animais , Camundongos , Diferenciação Celular , Memória Imunológica/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Sirolimo , Serina-Treonina Quinases TOR/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-39032850

RESUMO

OBJECTIVE: This study aims to assess the effectiveness of 5% dextrose (D5W) in comparison to corticosteroids for treating carpal tunnel syndrome (CTS). DATA SOURCES: A comprehensive systematic search was conducted across MEDLINE (PubMed), Embase, and the Cochrane Central Register of Controlled Trials on November 13, 2023. These were supplemented by manual searches using Google Scholar. STUDY SELECTION: Two independent authors reviewed the literature, resolving any discrepancies through detailed discussions and consultation with a third author. DATA EXTRACTION: Data on primary outcomes (pain assessment) and secondary outcomes (symptom severity and functional status using the Boston Carpal Tunnel Questionnaire, electrophysiologic measures, cross-sectional area, and adverse effects) were extracted independently by the 2 authors (M.W. and H.H.). DATA SYNTHESIS: The analysis included 4 randomized controlled trials and 1 quasi-experimental study, encompassing a total of 212 patients (220 hands) with mild to moderate CTS. RESULTS: Within 3 months, the D5W injections showed a statistically significant improvement in functional status compared to the corticosteroids with a standard mean difference of -0.34 (95% CI, -0.62 to -0.05). D5W was associated with fewer adverse incidents than corticosteroids (risk ratio, 0.13; 95% CI: 0.03-0.51). No difference was observed between the 2 treatments in other areas. CONCLUSIONS: For patients with mild to moderate CTS, D5W injections were more effective than corticosteroid injections in improving functional status and demonstrated fewer adverse effects. D5W injections also paralleled corticosteroids in pain reduction, symptom severity, electrodiagnostic measures, and cross-sectional area of nerve, recommending D5W as a preferred treatment for mild to moderate CTS.

10.
J Korean Med Sci ; 39(5): e50, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317450

RESUMO

BACKGROUND: Maladaptation to vascular, metabolic, and physiological changes during pregnancy can lead to fetal growth disorders. Moreover, adverse outcomes during pregnancy can further increase the risk of cardiovascular and metabolic diseases in mothers. Delivering a large-for-gestational-age (LGA) baby may indicate a pre-existing metabolic dysfunction, whereas delivering a small-for-gestational-age (SGA) baby may indicate a pre-existing vascular dysfunction. This study aims to assess the risk of hypertension (HTN) and diabetes mellitus (DM) in women with normal body mass index (BMI) scores who did not experience gestational DM or hypertensive disorders during pregnancy based on the offspring's birthweight. METHODS: This retrospective nationwide study included women with normal BMI scores who delivered a singleton baby after 37 weeks. Women with a history of DM or HTN before pregnancy and those with gestational DM or hypertensive disorders, were excluded from the study. We compared the risk of future maternal outcomes (HTN and DM) according to the offspring's birthweight. Multivariate analyses were performed to estimate the hazard ratio (HR) for the future risk of HTN or DM. RESULTS: A total of 64,037 women were included in the analysis. Of these, women who delivered very LGA babies (birthweight > 97th percentile) were at a higher risk of developing DM than those who delivered appropriate-for-gestational-age (AGA) babies (adjusted HR = 1.358 [1.068-1.727]), and women who delivered very SGA babies (birthweight < 3rd percentile) were at a higher risk of developing HTN than those who delivered AGA babies (adjusted HR = 1.431 [1.181-1.734]), even after adjusting for age, parity, gestational age at delivery, fetal sex, maternal BMI score, and a history of smoking. CONCLUSION: These findings provide a novel support for the use of the offspring's birthweight as a predictor of future maternal diseases such as HTN and DM.


Assuntos
Diabetes Gestacional , Hipertensão Induzida pela Gravidez , Gravidez , Feminino , Humanos , Peso ao Nascer , Índice de Massa Corporal , Estudos Retrospectivos , Hipertensão Induzida pela Gravidez/epidemiologia , Diabetes Gestacional/epidemiologia
11.
J Korean Med Sci ; 39(3): e33, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38258365

RESUMO

BACKGROUND: Over the last decade, extracorporeal membrane oxygenation (ECMO) use in critically ill children has increased and is associated with favorable outcomes. Our study aims to evaluate the current status of pediatric ECMO in Korea, with a specific focus on its volume and changes in survival rates based on diagnostic indications. METHODS: This multicenter study retrospectively analyzed the indications and outcomes of pediatric ECMO over 10 years in patients at 14 hospitals in Korea from January 2012 to December 2021. Four diagnostic categories (neonatal respiratory, pediatric respiratory, post-cardiotomy, and cardiac-medical) and trends were compared between periods 1 (2012-2016) and 2 (2017-2021). RESULTS: Overall, 1065 ECMO runs were performed on 1032 patients, with the annual number of cases remaining unchanged over the 10 years. ECMO was most frequently used for post-cardiotomy (42.4%), cardiac-medical (31.8%), pediatric respiratory (17.5%), and neonatal respiratory (8.2%) cases. A 3.7% increase and 6.1% decrease in pediatric respiratory and post-cardiotomy cases, respectively, were noted between periods 1 and 2. Among the four groups, the cardiac-medical group had the highest survival rate (51.2%), followed by the pediatric respiratory (46.4%), post-cardiotomy (36.5%), and neonatal respiratory (29.4%) groups. A consistent improvement was noted in patient survival over the 10 years, with a significant increase between the two periods from 38.2% to 47.1% (P = 0.004). Improvement in survival was evident in post-cardiotomy cases (30-45%, P = 0.002). Significant associations with mortality were observed in neonates, patients requiring dialysis, and those treated with extracorporeal cardiopulmonary resuscitation (P < 0.001). In pediatric respiratory ECMO, immunocompromised patients also showed a significant correlation with mortality (P < 0.001). CONCLUSION: Pediatric ECMO demonstrated a steady increase in overall survival in Korea; however, further efforts are needed since the outcomes remain suboptimal compared with global outcomes.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Recém-Nascido , Humanos , Criança , Estudos Retrospectivos , Coração , República da Coreia/epidemiologia
12.
Int Orthop ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39183229

RESUMO

PURPOSE: This study aimed to compare the surgical outcomes between bioabsorbable and metal screw fixation for distal tibial physeal fracture in children and adolescents, radiographically and clinically. METHODS: This study included consecutive 67 children and adolescents who underwent open reduction and internal fixation using metal or bioabsorbable screws for the distal tibia physeal fracture. All patients underwent preoperative radiographs, three-dimensional computed tomography scans, and postoperative follow-up teleradiogram. Patients were divided into metal (N = 40) and bioabsorbable groups (N = 27). We compared the surgical outcomes between the two groups in terms of clinical and radiographic outcomes, length of hospital stays, and medical cost. RESULTS: Follow-up duration were significantly longer in the metal group than that in the bioabsorbable group. There was no significant difference in the incidence of growth arrest after surgery and the scores of the Oxford Ankle and Foot Questionnaire between the two groups. However, the total hospital stay was significantly longer in the metal group (5.2 ± 4.8 days) compared to the bioabsorbable group (2.6 ± 0.5 days). Medical costs were significantly higher in the bioabsorbable group than in the metal group with a difference of 397 US dollars. CONCLUSIONS: The use of bioabsorbable screws exhibited therapeutic effects equivalent to that of metal screws for pediatric distal tibia physeal fractures regarding clinical and radiological outcomes. Moreover, it had the advantage of avoiding the need for repeated general anesthesia and secondary operation for implant removal. Therefore, the use of bioabsorbable screws may be a favourable surgical option for treating pediatric fractures.

13.
Medicina (Kaunas) ; 60(3)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38541188

RESUMO

Background and objectives: Musculoskeletal (MSK) pain significantly impacts physical activity and quality of life in older adults, potentially influencing mortality. This study explored the relationship between MSK pain, physical activity, muscle mass, and mortality among older adults. Material and Methods: We studied 1000 participants in the Korean Longitudinal Study on Health and Aging (KLoSHA), a prospective, population-based cohort study of people aged 65 years or older. Survival status was tracked over a 5-year period. Correlations between low back pain (LBP), knee pain, regular exercise, appendicular skeletal muscle mass (ASM), and other variables were analyzed. Logistic regression analyses were used to identify independent risk factors for mortality. Results: Of the total participants, 829 (82.9%) survived over a 5-year period. Survivors tended to be younger, had a higher BMI, and were more active in regular exercise. In contrast, non-survivors exhibited a higher prevalence of both LBP and knee pain, along with increased instances of multiple MSK pains. Lower ASM correlated moderately with LBP and knee pain, whereas higher ASM was associated with regular exercise. There was a moderate correlation between LBP and knee pain, both of which were associated with a lack of regular exercise. Age, sex, ASM, and regular exercise were significant predictors, even though MSK pain itself did not directly predict all-cause mortality. Conclusions: This study demonstrated the independent association between ASM, regular exercise, and mortality. Although MSK pain did not directly correlate with all-cause mortality, the non-survivor group had higher levels of both single and multiple MSK pains. Recognizing the interplay of MSK pain, physical activity, and muscle mass for older adults, the research underscores the need for holistic strategies to enhance health outcomes in older individuals with MSK pain.


Assuntos
Dor Lombar , Dor Musculoesquelética , Humanos , Idoso , Estudos Longitudinais , Estudos de Coortes , Qualidade de Vida , Estudos Prospectivos , Envelhecimento/fisiologia , Exercício Físico , República da Coreia/epidemiologia , Músculos
14.
Opt Express ; 31(17): 28112-28121, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710873

RESUMO

Optical phased array (OPA) beam scanners for light detection and ranging (LiDAR) are proposed by integrating polymer waveguides with superior thermo-optic effect and silicon nitride (SiN) waveguides exhibiting strong modal confinement along with high optical power capacity. A low connection loss of only 0.15 dB between the polymer and SiN waveguides was achieved in this work, enabling a low-loss OPA device. The polymer-SiN monolithic OPA demonstrates not only high optical throughput but also efficient beamforming and stable beam scanning. This novel integrative approach highlights the potential of leveraging heterogeneous photonic materials to develop advanced photonic integrated circuits with superior performance.

15.
Opt Express ; 31(3): 4760-4769, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785435

RESUMO

Polymer waveguide phase modulators (PMs) demonstrate high thermal confinement with outstanding thermo-optic properties and can provide stable low-power phase modulation in optical phased arrays (OPA). On the other hand, silicon nitride (SiN) waveguides produce stronger optical confinement with smaller waveguide core sizes than polymer waveguides and can handle high optical power without nonlinear effects. In this work, a high-performance PM was achieved by monolithic integration of a polymer waveguide and tapered SiN input and output waveguides. The integration of heterogeneous waveguide materials on a single substrate will enable the fabrication of efficient OPAs for advanced imaging, display, sensing, and communications applications.

16.
Biotechnol Bioeng ; 120(7): 2039-2044, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37042226

RESUMO

Streptomyces are important industrial bacteria that produce pharmaceutically valuable polyketides. However, mass production on an industrial scale is limited by low productivity, which can be overcome through metabolic engineering and the synthetic biology of the host strain. Recently, the introduction of an auto-inducible expression system depending on microbial physiological state has been suggested as an important tool for the industrial-scale production of polyketides. In this study, titer improvement by enhancing the pool of CoA-derived precursors required for polyketide production was driven in a quorum sensing (QS)-dependent manner. A self-sustaining and inducer-independent regulatory system, named the QS-based metabolic engineering of precursor pool (QMP) system, was constructed, wherein the expression of genes involved in precursor biosynthesis was regulated by the QS-responsive promoter, scbAp. The QMP system was applied for neoaureothin production in a heterologous host, Streptomyces coelicolor M1152, and productivity increased by up to 4-fold. In particular, the engineered hyperproducers produced high levels of neoaureothin without adversely affecting cell growth. Overall, this study showed that self-regulated metabolic engineering mediated by QS has the potential to engineer strains for polyketide titer improvement.


Assuntos
Policetídeos , Streptomyces coelicolor , Streptomyces , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Engenharia Metabólica , Percepção de Quorum/genética , Streptomyces/genética , Policetídeos/metabolismo
17.
Microb Cell Fact ; 22(1): 212, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37838667

RESUMO

BACKGROUND: Oviedomycin is one among several polyketides known for their potential as anticancer agents. The biosynthetic gene cluster (BGC) for oviedomycin is primarily found in Streptomyces antibioticus. However, because this BGC is usually inactive under normal laboratory conditions, it is necessary to employ systematic metabolic engineering methods, such as heterologous expression, refactoring of BGCs, and optimization of precursor biosynthesis, to allow efficient production of these compounds. RESULTS: Oviedomycin BGC was captured from the genome of Streptomyces antibioticus by a newly constructed plasmid, pCBA, and conjugated into the heterologous strain, S. coelicolor M1152. To increase the production of oviedomycin, clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system was utilized in an in vitro setting to refactor the native promoters within the ovm BGC. The target promoters of refactoring were selected based on examination of factors such as transcription levels and metabolite profiling. Furthermore, genome-scale metabolic simulation was applied to find overexpression targets that could enhance the biosynthesis of precursors or cofactors related to oviedomycin production. The combined approach led to a significant increase in oviedomycin production, reaching up to 670 mg/L, which is the highest titer reported to date. This demonstrates the potential of the approach undertaken in this study. CONCLUSIONS: The metabolic engineering approach used in this study led to the successful production of a valuable polyketide, oviedomycin, via BGC cloning, promoter refactoring, and gene manipulation of host metabolism aided by genome-scale metabolic simulation. This approach can be also useful for the efficient production of other secondary molecules encoded by 'silent' BGCs.


Assuntos
Policetídeos , Streptomyces coelicolor , Streptomyces , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Engenharia Metabólica/métodos , Streptomyces/genética , Policetídeos/metabolismo , Família Multigênica
18.
BJOG ; 130(11): 1370-1378, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37077036

RESUMO

OBJECTIVE: To evaluate long-term adverse neurodevelopmental outcomes of discordant twins delivered at term. DESIGN: Retrospective cohort study. SETTING: Nationwide (Republic of Korea). POPULATION: All twin children delivered at term between 2007 and 2010. METHODS: The study population was divided into two groups according to inter-twin birthweight discordancy: the 'concordant twin group', twin pairs with inter-twin birthweight discordancy less than 20%; and the 'discordant twin group', twin pairs with inter-twin birthweight discordancy of 20% or more. The risk of long-term adverse neurodevelopmental outcomes was compared between the concordant twin group and the discordant twin group. Long-term adverse neurodevelopmental outcomes between smaller and larger twin children within twin pairs were further analysed. The composite adverse neurodevelopmental outcome was defined as the presence of at least one of the following: motor developmental delay, cognitive developmental delay, autism spectrum disorders/attention deficit hyperactivity disorders, tics/stereotypical behaviour or epileptic/febrile seizure. MAIN OUTCOME MEASURES: Long-term adverse neurodevelopmental outcome. RESULTS: Of 22 468 twin children (11 234 pairs) included, 3412 (15.19%) twin children were discordant. The risk of composite adverse neurodevelopmental outcome was higher in the discordant twin group than in the concordant twin group (adjusted hazard ratio [HR] 1.13, 95% CI 1.03-1.24). The long-term adverse neurodevelopmental outcomes were not significantly different between smaller and larger twin children in discordant twin pairs (adjusted HR 1.01, 95% CI 0.81-1.28). CONCLUSION: In twin pairs delivered at term, an inter-twin birthweight discordancy of 20% or greater was associated with long-term adverse neurodevelopmental outcomes; and long-term adverse neurodevelopmental outcomes were not significantly different in smaller or larger twin children in discordant twin pairs.


Assuntos
Doenças do Recém-Nascido , Complicações na Gravidez , Criança , Feminino , Humanos , Recém-Nascido , Peso ao Nascer , Doenças em Gêmeos , Estudos Retrospectivos , Convulsões , Gêmeos
19.
J Immunol ; 207(3): 913-922, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34290107

RESUMO

Metabolic programming is integrally linked to immune cell function. Nowhere is this clearer than in the differentiation of macrophages. Proinflammatory M1 macrophages primarily use glycolysis as a rapid energy source but also to generate antimicrobial compounds, whereas alternatively activated M2 macrophages primarily rely on oxidative phosphorylation for the longevity required for proper wound healing. mTOR signaling has been demonstrated to be a key regulator of immune cell metabolism and function. mTORC2 signaling is required for the generation of M2 macrophages, whereas the role of mTORC1 signaling, a key regulator of glycolysis, has been controversial. By using genetic deletion of mTORC1 signaling in C57BL/6 mouse macrophages, we observed enhanced M1 macrophage function in vitro and in vivo. Surprisingly, this enhancement occurred despite a significant defect in M1 macrophage glycolytic metabolism. Mechanistically, enhanced M1 function occurred because of inhibition of the class III histone deacetylases the sirtuins, resulting in enhanced histone acetylation. Our findings provide a counterpoint to the paradigm that enhanced immune cell function must occur in the presence of increased cellular metabolism and identifies a potential, pharmacologic target for the regulation of inflammatory responses.


Assuntos
Inflamação/imunologia , Macrófagos/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Acetilação , Animais , Células Cultivadas , Reprogramação Celular , Citocinas/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Sirtuínas/metabolismo , Células Th1/imunologia
20.
Nucleic Acids Res ; 49(11): 6596-6603, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110422

RESUMO

DNA origami requires long scaffold DNA to be aligned with the guidance of short staple DNA strands. Scaffold DNA is produced in Escherichia coli as a form of the M13 bacteriophage by rolling circle amplification (RCA). This study shows that RCA can be reconfigured by reducing phage protein V (pV) expression, improving the production throughput of scaffold DNA by at least 5.66-fold. The change in pV expression was executed by modifying the untranslated region sequence and monitored using a reporter green fluorescence protein fused to pV. In a separate experiment, pV expression was controlled by an inducer. In both experiments, reduced pV expression was correlated with improved M13 bacteriophage production. High-cell-density cultivation was attempted for mass scaffold DNA production, and the produced scaffold DNA was successfully folded into a barrel shape without compromising structural quality. This result suggested that scaffold DNA production throughput can be significantly improved by reprogramming the RCA in E. coli.


Assuntos
Bacteriófago M13/fisiologia , DNA de Cadeia Simples/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas Virais/genética , Regiões 5' não Traduzidas , Bacteriófago M13/genética , Bacteriófago M13/metabolismo , DNA de Cadeia Simples/ultraestrutura , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Mutação , Proteínas Virais/metabolismo , Replicação Viral
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