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1.
Nat Immunol ; 25(5): 790-801, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38664585

RESUMO

Innate immune cells generate a multifaceted antitumor immune response, including the conservation of essential nutrients such as iron. These cells can be modulated by commensal bacteria; however, identifying and understanding how this occurs is a challenge. Here we show that the food commensal Lactiplantibacillus plantarum IMB19 augments antitumor immunity in syngeneic and xenograft mouse tumor models. Its capsular heteropolysaccharide is the major effector molecule, functioning as a ligand for TLR2. In a two-pronged manner, it skews tumor-associated macrophages to a classically active phenotype, leading to generation of a sustained CD8+ T cell response, and triggers macrophage 'nutritional immunity' to deploy the high-affinity iron transporter lipocalin-2 for capturing and sequestering iron in the tumor microenvironment. This process induces a cycle of tumor cell death, epitope expansion and subsequent tumor clearance. Together these data indicate that food commensals might be identified and developed into 'oncobiotics' for a multi-layered approach to cancer therapy.


Assuntos
Ferro , Microambiente Tumoral , Animais , Ferro/metabolismo , Camundongos , Microambiente Tumoral/imunologia , Humanos , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/imunologia , Camundongos Endogâmicos C57BL , Lipocalina-2/metabolismo , Lipocalina-2/imunologia , Feminino , Simbiose/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Ativação de Macrófagos/imunologia , Camundongos Knockout
2.
J Org Chem ; 89(12): 8985-9000, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38861548

RESUMO

Ketyl radicals are synthetically versatile reactive species, but their applications have been hampered by harsh generation conditions employing highly reducing metals. Recently, the pyridine-boryl radical received wide attention as a promising organic reductant because of its mildness as well as convenience in handling. While probing the utility of the pyridine-boryl radical, our group observed facile pinacol coupling reactivity that had not been known at that time. This serendipitous finding was successfully rendered into a practical synthesis of tetraaryl-1,2-diols in up to 99% yield within 1 h. Subsequently, upon examinations of various reaction manifolds, a diastereoselective ketyl-olefin cyclization was accomplished to produce cycloalkanols such as trans-2-alkyl-1-indanols. Compared to the previous methods, the stereocontrolling ability was considerably enhanced by taking advantage of the structurally modifiable boryl group that would be present near the bond-forming site. In this full account, our synthetic efforts with the O-boryl ketyl radicals are disclosed in detail, covering the discovery, optimization, scope expansion, and mechanistic analysis, including density functional theory (DFT) calculations.

3.
Cancer Immunol Immunother ; 72(8): 2757-2768, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37165046

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) remains a devastating cancer due to its poor survival rate, early detection, and resectability. This study aimed to determine the peripheral blood mononuclear cell (PBMC) immune biomarkers in patients with PDAC and investigate the PDAC-specific peripheral blood biomarker panel and validate its clinical performance. METHODS: In this prospective, blinded, case-control study, a biomarker panel formula was generated using a development cohort-including healthy controls, patients at high risk of PDAC, and patients with benign pancreatic disease, PDAC, or other gastrointestinal malignancies-and its diagnostic performance was verified using a validation cohort, including patients with ≥ 1 lesion suspected as PDAC on computed tomography (CT). RESULTS: RNA-sequencing of PBMCs from patients with PDAC identified three novel immune cell markers, IL-7R, PLD4, and ID3, as specific markers for PDAC. Regarding the diagnostic performance of the regression formula for the three biomarker panels, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 84.0%, 78.8%, 47.2%, 95.6%, and 79.8%, respectively. Based on the formula scores for the biomarker panel, the false-negative rate (FNR) of the biomarkers was 8% (95% confidence interval [CI] 3.0-13.0), which was significantly lower than that based on CT in the validation cohort (29.2%, 95% CI 20.8-37.6). CONCLUSIONS: The regression formula constructed using three PBMC biomarkers is an inexpensive, rapid, and convenient method that shows clinically useful performance for the diagnosis of PDAC. It aids diagnoses and differential diagnoses of PDAC from pancreatic disease by lowering the FNR compared to CT. Clinical trial registration Clinical Research Information Service, KCT0004614 (08 January 2020).


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Leucócitos Mononucleares , Estudos de Casos e Controles , Estudos Prospectivos , Biomarcadores Tumorais/genética , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , RNA Mensageiro , RNA , Neoplasias Pancreáticas
4.
Sensors (Basel) ; 23(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850862

RESUMO

Hysteresis in organic field-effect transistors is attributed to the well-known bias stress effects. This is a phenomenon in which the measured drain-source current varies when sweeping the gate voltage from on to off or from off to on. Hysteresis is caused by various factors, and one of the most common is charge trapping. A charge trap is a defect that occurs in an interface state or part of a semiconductor, and it refers to an electronic state that appears distributed in the semiconductor's energy band gap. Extensive research has been conducted recently on obtaining a better understanding of charge traps for hysteresis. However, it is still difficult to accurately measure or characterize them, and their effects on the hysteresis of organic transistors remain largely unknown. In this study, we conduct a literature survey on the hysteresis caused by charge traps from various perspectives. We first analyze the driving principle of organic transistors and introduce various types of hysteresis. Subsequently, we analyze charge traps and determine their influence on hysteresis. In particular, we analyze various estimation models for the traps and the dynamics of the hysteresis generated through these traps. Lastly, we conclude this study by explaining the causal inference approach, which is a machine learning technique typically used for current data analysis, and its implementation for the quantitative analysis of the causal relationship between the hysteresis and the traps.

5.
BMC Oral Health ; 22(1): 164, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524204

RESUMO

BACKGROUND: This study aimed to develop and validate five machine learning models designed to predict actinomycotic osteomyelitis of the jaw. Furthermore, this study determined the relative importance of the predictive variables for actinomycotic osteomyelitis of the jaw, which are crucial for clinical decision-making. METHODS: A total of 222 patients with osteomyelitis of the jaw were analyzed, and Actinomyces were identified in 70 cases (31.5%). Logistic regression, random forest, support vector machine, artificial neural network, and extreme gradient boosting machine learning methods were used to train the models. The models were subsequently validated using testing datasets. These models were compared with each other and also with single predictors, such as age, using area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: The AUC of the machine learning models ranged from 0.81 to 0.88. The performance of the machine learning models, such as random forest, support vector machine and extreme gradient boosting was significantly superior to that of single predictors. Presumed causes, antiresorptive agents, age, malignancy, hypertension, and rheumatoid arthritis were the six features that were identified as relevant predictors. CONCLUSIONS: This prediction model would improve the overall patient care by enhancing prognosis counseling and informing treatment decisions for high-risk groups of actinomycotic osteomyelitis of the jaw.


Assuntos
Aprendizado de Máquina , Osteomielite , Diagnóstico Precoce , Humanos , Modelos Logísticos , Osteomielite/diagnóstico , Curva ROC
6.
Nat Chem Biol ; 15(9): 907-916, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427815

RESUMO

Toll-like receptor (TLR)/myeloid differentiation primary response protein (MYD88) signaling aggravates sepsis by impairing neutrophil migration to infection sites. However, the role of intracellular fatty acids in TLR/MYD88 signaling is unclear. Here, inhibition of fatty acid synthase by C75 improved neutrophil chemotaxis and increased the survival of mice with sepsis in cecal ligation puncture and lipopolysaccharide-induced septic shock models. C75 specifically blocked TLR/MYD88 signaling in neutrophils. Treatment with GSK2194069 that targets a different domain of fatty acid synthase, did not block TLR signaling or MYD88 palmitoylation. De novo fatty acid synthesis and CD36-mediated exogenous fatty acid incorporation contributed to MYD88 palmitoylation. The binding of IRAK4 to the MYD88 intermediate domain and downstream signal activation required MYD88 palmitoylation at cysteine 113. MYD88 was palmitoylated by ZDHHC6, and ZDHHC6 knockdown decreased MYD88 palmitoylation and TLR/MYD88 activation upon lipopolysaccharide stimulus. Thus, intracellular saturated fatty acid-dependent palmitoylation of MYD88 by ZDHHC6 is a therapeutic target of sepsis.


Assuntos
Receptores Toll-Like/metabolismo , Animais , Linhagem Celular , Ácido Graxo Sintase Tipo I , Humanos , Inflamação , Lipoilação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
7.
Hippocampus ; 30(11): 1158-1166, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32644222

RESUMO

Neur1 and Neur2, mouse homologs of the Drosophila neur gene, consist of two neuralized homology repeat domains and a RING domain. Both Neur1 and Neur2 are expressed in the whole adult brain and encode E3 ubiquitin ligases, which play a crucial role in the Notch signaling pathways. A previous study reported that overexpression of Neur1 enhances hippocampus-dependent memory, whereas the role of Neur2 remains largely unknown. Here, we aimed to elucidate the respective roles of Neur1 and Neur2 in hippocampus-dependent memory using three lines of genetically modified mice: Neur1 knock-out, Neur2 knock-out, and Neur1 and Neur2 double knock-out (D-KO). Our results showed that spatial memory was impaired when both Neur1 and Neur2 were deleted, but not in the individual knock-out of either Neur1 or Neur2. In addition, basal synaptic properties estimated by input-output relationships and paired-pulse facilitation did not change, but a form of long-term potentiation that requires protein synthesis was specifically impaired in the D-KO mice. These results collectively suggest that Neur1 and Neur2 are crucially involved in hippocampus-dependent spatial memory and synaptic plasticity.


Assuntos
Hipocampo/metabolismo , Proteínas do Tecido Nervoso/deficiência , Plasticidade Neuronal/fisiologia , Proteínas Repressoras/deficiência , Memória Espacial/fisiologia , Complexos Ubiquitina-Proteína Ligase/deficiência , Animais , Feminino , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas Repressoras/genética , Complexos Ubiquitina-Proteína Ligase/genética
8.
Neurobiol Learn Mem ; 169: 107171, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31978552

RESUMO

Memory is stored in our brains over a temporally graded transition. With time, recently formed memories are transformed into remote memories for permanent storage; multiple brain regions, such as the hippocampus and neocortex, participate in this process. In this study, we aimed to understand the molecular mechanism of systems consolidation of memory and to investigate the brain regions that contribute to this regulation. We first carried out a contextual fear memory test using a transgenic mouse line, which expressed exogenously-derived Aplysia octopamine receptors in the forebrain region, such that, in response to octopamine treatment, cyclic adenosine monophosphate (cAMP) levels could be transiently elevated. From this experiment, we revealed that transient elevation of cAMP levels in the forebrain during systems consolidation led to an enhancement in remote fear memory and increased miniature excitatory synaptic currents in layer II/III of the anterior cingulate cortex (ACC). Furthermore, using an adeno-associated-virus-driven DREADD system, we investigated the specific regions in the forebrain that contribute to the regulation of memory transfer into long-term associations. Our results implied that transient elevation of cAMP levels was induced chemogenetically in the ACC, but not in the hippocampus, and showed a significant enhancement of remote memory. This finding suggests that neuronal activation during systems consolidation through the elevation of cAMP levels in the ACC contributes to remote memory enhancement.


Assuntos
AMP Cíclico/fisiologia , Medo/fisiologia , Giro do Cíngulo/fisiologia , Hipocampo/fisiologia , Consolidação da Memória/fisiologia , Memória de Longo Prazo/fisiologia , Neurônios/fisiologia , Animais , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
9.
J Neurosci ; 38(22): 5042-5052, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29712785

RESUMO

The molecular mechanism of long-term memory has been extensively studied in the context of the hippocampus-dependent recent memory examined within several days. However, months-old remote memory maintained in the cortex for long-term has not been investigated much at the molecular level yet. Various epigenetic mechanisms are known to be important for long-term memory, but how the 3D chromatin architecture and its regulator molecules contribute to neuronal plasticity and systems consolidation is still largely unknown. CCCTC-binding factor (CTCF) is an 11-zinc finger protein well known for its role as a genome architecture molecule. Male conditional knock-out mice in which CTCF is lost in excitatory neurons during adulthood showed normal recent memory in the contextual fear conditioning and spatial water maze tasks. However, they showed remarkable impairments in remote memory in both tasks. Underlying the remote memory-specific phenotypes, we observed that female CTCF conditional knock-out mice exhibit disrupted cortical LTP, but not hippocampal LTP. Similarly, we observed that CTCF deletion in inhibitory neurons caused partial impairment of remote memory. Through RNA sequencing, we observed that CTCF knockdown in cortical neuron culture caused altered expression of genes that are highly involved in cell adhesion, synaptic plasticity, and memory. These results suggest that remote memory storage in the cortex requires CTCF-mediated gene regulation in neurons, whereas recent memory formation in the hippocampus does not.SIGNIFICANCE STATEMENT CCCTC-binding factor (CTCF) is a well-known 3D genome architectural protein that regulates gene expression. Here, we use two different CTCF conditional knock-out mouse lines and reveal, for the first time, that CTCF is critically involved in the regulation of remote memory. We also show that CTCF is necessary for appropriate expression of genes, many of which we found to be involved in the learning- and memory-related processes. Our study provides behavioral and physiological evidence for the involvement of CTCF-mediated gene regulation in the remote long-term memory and elucidates our understanding of systems consolidation mechanisms.


Assuntos
Fator de Ligação a CCCTC/fisiologia , Córtex Cerebral/fisiologia , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Adesão Celular/fisiologia , Condicionamento Clássico , Potenciais Pós-Sinápticos Excitadores/genética , Potenciais Pós-Sinápticos Excitadores/fisiologia , Medo , Regulação da Expressão Gênica , Potenciação de Longa Duração/fisiologia , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Knockout , Percepção Espacial/fisiologia
10.
Neurochem Res ; 44(3): 676-682, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29076061

RESUMO

The sirtuin family of proteins consists of nicotinamide adenine dinucleotide-dependent deacetylases that are involved in the response to calorie restriction and various physiological phenomena, such as aging and cognition. One of these proteins, sirtuin 3 (SIRT3), is localized in the mitochondria and protects the cell against oxidative or metabolic stress. Sirtuin protein deficiencies have been shown to accelerate neurodegeneration in neurotoxic conditions. The mechanisms underlying the involvement of SIRT3 in cognition remain unclear. Interestingly, SIRT1, another member of the sirtuin family, has been reported to modulate synaptic plasticity and memory formation. To learn more about these proteins, we examined the behavior and cognitive functions of Sirt3-knockout mice. The mice exhibited poor remote memory. Consistent with this, long-term potentiation was impaired in the Sirt3-knockout mice, and they exhibited decreased neuronal number in the anterior cingulate cortex, which seemed to contribute to their memory deficiencies.


Assuntos
Potenciação de Longa Duração/fisiologia , Memória de Longo Prazo/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Sirtuína 3/deficiência , Animais , Potenciação de Longa Duração/genética , Memória/fisiologia , Camundongos Knockout , Mitocôndrias/metabolismo , Plasticidade Neuronal/genética , Sirtuína 1/genética
11.
J Oral Maxillofac Surg ; 77(2): 280-288, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30315791

RESUMO

PURPOSE: Disorders of the temporomandibular joint (TMJ) occur frequently, with a prevalence of 15 to 18%. Total joint replacement (TJR) surgery is indicated for severe joint damage associated with impaired function, pain, or occlusal change for which other treatments have been unsuccessful. The aim of this study was to assess changes in pain and range of motion (ROM), as well as postoperative complications and comorbidities, in patients receiving TJR surgery at Massachusetts General Hospital (MGH). PATIENTS AND METHODS: This study is a retrospective review that describes the clinical variables in patients after alloplastic TMJ reconstruction performed at MGH from 2000 to 2015. Clinical variables included primary diagnosis; number of previous surgical procedures; comorbidities; preoperative and postoperative pain; preoperative, intraoperative, and postoperative ROM; and complications. RESULTS: Data were obtained from 95 patients undergoing a total of 108 surgical procedures, with an average follow-up period of 4.48 ± 3.38 years. The most common primary indications for TJR were ankylosis (44%) and inflammatory disease (23%). The maximum interincisal opening improved by a mean of 7.7 ± 10.27 mm, and pain decreased by a mean of 1.5 ± 3.29 points on a visual analog scale. Transient facial nerve palsy (25%) was the most common postoperative complication; however, long-term complications were rare. The most frequent comorbidities were psychiatric disorders (56%) and gastrointestinal disease (46%). Psychiatric patients had similar preoperative pain scores (6.0 ± 2.90) but significantly higher postoperative pain scores (4.7 ± 2.58) compared with nonpsychiatric patients. Twenty-eight percent of patients had prior failed TMJ implant materials, specifically Proplast-Teflon (Vitek, Houston, TX). These patients were significantly older (50.4 ± 8.26 years) and had smaller preoperative ROM (21.7 ± 8.85 mm) and smaller postoperative ROM (28.3 ± 9.59 mm). CONCLUSIONS: Patients showed a statistically significant (P < .01) increase in ROM and reduction in pain. TJR is an effective treatment option in patients with limited mouth opening or severe pain.


Assuntos
Artroplastia de Substituição , Prótese Articular , Transtornos da Articulação Temporomandibular , Anquilose Dental , Hospitais Gerais , Humanos , Massachusetts , Amplitude de Movimento Articular , Estudos Retrospectivos , Articulação Temporomandibular , Transtornos da Articulação Temporomandibular/cirurgia , Resultado do Tratamento
12.
FASEB J ; 31(4): 1461-1481, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28073834

RESUMO

Membrane proteins sense extracellular cues and transduce intracellular signaling to coordinate directionality and speed during cellular migration. They are often localized to specific regions, as with lipid rafts or tetraspanin-enriched microdomains; however, the dynamic interactions of tetraspanins with diverse receptors within tetraspanin-enriched microdomains on cellular surfaces remain largely unexplored. Here, we investigated effects of tetraspan(in) TM4SF5 (transmembrane 4 L6 family member 5)-enriched microdomains (T5ERMs) on the directionality of cell migration. Physical association of TM4SF5 with epidermal growth factor receptor (EGFR) and integrin α5 was visualized by live fluorescence cross-correlation spectroscopy and higher-resolution microscopy at the leading edge of migratory cells, presumably forming TM4SF5-enriched microdomains. Whereas TM4SF5 and EGFR colocalized at the migrating leading region more than at the rear, TM4SF5 and integrin α5 colocalized evenly throughout cells. Cholesterol depletion and disruption in TM4SF5 post-translational modifications, including N-glycosylation and palmitoylation, altered TM4SF5 interactions and cellular localization, which led to less cellular migration speed and directionality in 2- or 3-dimensional conditions. TM4SF5 controlled directional cell migration and invasion, and importantly, these TM4SF5 functions were dependent on cholesterol, TM4SF5 post-translational modifications, and EGFR and integrin α5 activity. Altogether, we showed that TM4SF5 dynamically interacted with EGFR and integrin α5 in migratory cells to control directionality and invasion.-Kim, H.-J., Kwon, S., Nam, S. H., Jung, J. W., Kang, M., Ryu, J., Kim, J. E., Cheong, J.-G., Cho, C. Y., Kim, S., Song, D.-G., Kim, Y.-N., Kim, T. Y., Jung, M.-K., Lee, K.-M., Pack, C.-G., Lee, J. W. Dynamic and coordinated single-molecular interactions at TM4SF5-enriched microdomains guide invasive behaviors in 2- and 3-dimensional environments.


Assuntos
Microdomínios da Membrana/metabolismo , Proteínas de Membrana/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Colesterol/metabolismo , Receptores ErbB/metabolismo , Glicosilação , Células HEK293 , Hepatócitos/metabolismo , Hepatócitos/fisiologia , Hepatócitos/ultraestrutura , Humanos , Integrina alfa5/metabolismo , Lipoilação , Microdomínios da Membrana/ultraestrutura , Ligação Proteica , Processamento de Proteína Pós-Traducional
13.
J Oral Maxillofac Surg ; 76(10): 2169-2176, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29654777

RESUMO

PURPOSE: There is no universally accepted method for determining the ideal sagittal position of the maxilla in orthognathic surgery. In "Element II" of "The Six Elements of Orofacial Harmony," Andrews used the forehead to define the goal maxillary position. The purpose of this study was to compare how well this analysis correlated with postoperative findings in patients who underwent bimaxillary orthognathic surgery planned using other guidelines. The authors hypothesized that the Andrews analysis would more consistently reflect clinical outcomes than standard angular and linear measurements. MATERIALS AND METHODS: This is a retrospective cohort study of patients who had bimaxillary orthognathic surgery and achieved an acceptable esthetic outcome. Patients with no maxillary sagittal movement, obstructive sleep apnea, cleft or craniofacial diagnoses, or who were non-Caucasian were excluded. Treatment plans were developed using photographs, radiographs, and standard cephalometric measurements. The Andrews analysis, measuring the distance from the maxillary incisor to the goal anterior limit line, and standard measurements were applied to end-treatment records. The Andrews analysis was statistically compared with standard methods. RESULTS: There were 493 patients who had orthognathic surgery from 2007 through 2014, and 60 (62% women; mean age, 22.1 ± 6.8 yr) met the criteria for inclusion in this study. The mean Andrews distances were -4.8 ± 2.9 mm for women and -8.6 ± 4.6 mm for men preoperatively and -0.6 ± 2.1 mm for women and -1.9 ± 3.4 mm for men postoperatively. For women, the Andrews analysis was closer to the goal value (0 mm) postoperatively than any standard measurement (P < .001). For men, the linear distance from the A point to a vertical line tangent to the nasion from the McNamara analysis performed best (P < .001), followed by the Andrews analysis. CONCLUSION: The Andrews analysis correlated well with the final esthetic sagittal maxillary position in the present sample, particularly for women, and could be a useful tool for orthognathic surgical planning.


Assuntos
Cefalometria/métodos , Maxila/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Adolescente , Adulto , Pontos de Referência Anatômicos , Estética Dentária , Feminino , Humanos , Masculino , Maxila/diagnóstico por imagem , Estudos Retrospectivos
14.
J Biol Chem ; 291(28): 14620-7, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27226621

RESUMO

Although it has been established that diabetes increases susceptibility to infections, the role of insulin (INS) in the immune response is unknown. Here, we investigated the immunological function of INS. Proinsulin dimer (pINSd) was a potent immune stimulus that induced inflammatory cytokines, but mature INS was unable to induce an immune response. An affinity-purified rabbit polyclonal antibody raised against mature IL-1α recognized IL-1α and pINS but failed to detect mature INS and IL-1ß. Analysis of the pINS sequence revealed the existence of an INS/IL-1α motif in the C-peptide of pINS. Surprisingly, the INS/IL-1α motif was recognized by monoclonal antibody raised against IL-1α. Deleting the INS/IL-1α motif in pINSd and IL-1α changed their activities. To investigate the pINSd receptor, the reconstitution of IL-1 receptor 1 (IL-1R1) in Wish cells restored pINSd activity that was reversed by an IL-1R antagonist. These data suggested that pINSd needs IL-1R1 for inflammatory cytokine induction. Mouse embryo fibroblast cells of IL-1R1-deficient mice further confirmed that pINSd promotes immune responses through IL-1R1.


Assuntos
Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , Interleucina-1alfa/metabolismo , Proinsulina/metabolismo , Receptores de Interleucina-1/metabolismo , Animais , Células Cultivadas , Interleucina-1alfa/química , Camundongos , Proinsulina/química
15.
Clin Endocrinol (Oxf) ; 87(5): 523-531, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28581026

RESUMO

OBJECTIVES: This study evaluated an association between testosterone, sex hormone-binding globulin (SHBG) and metabolic syndrome (MetS).We also evaluated the genetic and environmental influences on the association. DESIGN: Cross-sectional. SETTING: Community-based study. PARTICIPANTS: A total of 1098 Korean adult men including 139 monozygotic twin pairs. MAIN OUTCOME MEASURE: MetS was defined using the National Cholesterol Education Program-Third Adult Treatment Panel (NCEP ATP III) and International Diabetes Federation (IDF) criteria. The associations between MetS and sex hormones were evaluated using linear mixed model and generalized estimating equation model. RESULTS: After considering covariates such as smoking, alcohol consumption and physical exercises as well as SHBG or testosterone, the risk of MetS defined by NCEP ATP III criteria decreased by 31%, 29%, and 48%, respectively, with 1-standard deviation increase in total testosterone (TT), free testosterone (cFT) and SHBG. Similar findings were revealed with IDF criteria. Metabolic component specific analysis showed that sex hormones were inversely associated with several components of MetS: TT with abdominal obesity, low high-density lipoprotein cholesterol (HDL-C) and high blood pressure; cFT with abdominal obesity and high blood pressure; SHBG with all components except high blood pressure. Cotwin control analysis found an inverse correlation between within-pair differences in testosterone and SHBG levels and within-pair differences in waist circumference only. CONCLUSION: Both testosterone and SHBG were inversely associated with MetS although the inverse associations with the sex hormones were not consistently found across individual metabolic components. Findings from cotwin analysis suggest a significant contribution of unshared unique environmental effect to the association between testosterone and SHBG and abdominal obesity.


Assuntos
Síndrome Metabólica/sangue , Obesidade Abdominal/sangue , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Adulto , Estudos Transversais , Meio Ambiente , Hormônios Gonadais/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Gêmeos Monozigóticos , Circunferência da Cintura
16.
Mol Pharm ; 14(9): 3059-3068, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28704054

RESUMO

Angiogenesis mainly mediated by upregulation of vascular endothelial growth factor (VEGF) provides a hallmark of rapidly proliferating tumor cells and an essential component of the tumor growth and microenvironment, making it a targetable process for antitumor therapy. RNA interference (RNAi) provides a very effective tool for developing antitumor therapies; however, its application to date has been hampered due to the lack of efficient small interfering RNA (siRNA) delivery systems in vivo. Here, we report a polymeric gene carrier system based on PEGylation of a cationic cysteine-ended 9-mer arginine oligopeptide (CR9C), which provides effective siRNA systemic delivery and specifically suppresses VEGF (siVEGF). The PEG500-CR9C/siVEGF oligopeptoplex provided improved blood circulation, enhanced protection from serum proteases, reduced uptake in the liver and kidneys, enhanced tumor targeting, and down-regulated intratumoral VEGF level, which comprehensively resulted in improved antitumor efficacy without significant toxicity in vivo. PEG500-CR9C has a great potential for safe and efficient siRNA delivery with diverse applications.


Assuntos
Arginina/química , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Linhagem Celular Tumoral , Terapia Genética , Humanos , Masculino , Camundongos , Camundongos Nus , Microscopia Confocal , Nanopartículas/química , Polietilenoglicóis/química , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Proc Natl Acad Sci U S A ; 111(49): 17672-7, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25422419

RESUMO

Many plants measure changes in day length to synchronize their flowering time with appropriate seasons for maximum reproductive success. In Arabidopsis, the day-length-dependent regulation of Constans (CO) protein stability is crucial to induce flowering locus T (FT) expression for flowering in long days. The flavin-binding, KELCH repeat, F-box1 (FKF1) protein binds to CO protein specifically in the long-day afternoon and stabilizes it, although the mechanism remains unknown. Here we demonstrated that the FKF1-interacting proteins Gigantea (GI) and Zeitlupe (ZTL) are involved in CO stability regulation. First, our immunoprecipitation-mass spectrometry analysis of FKF1 revealed that FKF1 forms an S-phase kinase-associated protein 1 (Skp1)/Cullin(CUL)/F-box complex through interactions with Arabidopsis Skp1-like 1 (ASK1), ASK2, and CUL1 proteins and mainly interacts with GI protein in vivo. GI interacts with CO directly and indirectly through FKF1. Unexpectedly, the gi mutation increases the CO protein levels in the morning in long days. This gi-dependent destabilization of CO protein was cancelled by the fkf1 mutation. These results suggest that there are other factors likely influenced by both gi and fkf1 mutations that also control CO stability. We found that ZTL, which interacts with GI and FKF1, may be one such factor. ZTL also interacts with CO in vivo. The CO protein profile in the ztl mutant resembles that in the gi mutant, indicating that ZTL activity also may be changed in the gi mutant. Our findings suggest the presence of balanced regulation among FKF1, GI, and ZTL on CO stability regulation for the precise control of flowering time.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/genética , Proteínas de Ligação a DNA/fisiologia , Flores/fisiologia , Fotoperíodo , Fatores de Transcrição/fisiologia , Arabidopsis/fisiologia , Núcleo Celular/metabolismo , Flores/genética , Regulação da Expressão Gênica de Plantas , Luz , Mutação , Regiões Promotoras Genéticas , Estações do Ano , Transdução de Sinais , Ubiquitina-Proteína Ligases/fisiologia
18.
Korean J Physiol Pharmacol ; 19(6): 515-22, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26557018

RESUMO

Notch signaling is a key regulator of neuronal fate during embryonic development, but its function in the adult brain is still largely unknown. Mind bomb-2 (Mib2) is an essential positive regulator of the Notch pathway, which acts in the Notch signal-sending cells. Therefore, genetic deletion of Mib2 in the mouse brain might help understand Notch signaling-mediated cell-cell interactions between neurons and their physiological function. Here we show that deletion of Mib2 in the mouse brain results in impaired hippocampal spatial memory and contextual fear memory. Accordingly, we found impaired hippocampal synaptic plasticity in Mib2 knock-out (KO) mice; however, basal synaptic transmission did not change at the Schaffer collateral-CA1 synapses. Using western blot analysis, we found that the level of cleaved Notch1 was lower in Mib2 KO mice than in wild type (WT) littermates after mild foot shock. Taken together, these data suggest that Mib2 plays a critical role in synaptic plasticity and spatial memory through the Notch signaling pathway.

19.
Small Methods ; 8(2): e2300391, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37231569

RESUMO

Instead of the current method of transmitting voltage or current signals in electronic circuit operation, light offers an alternative to conventional logic, allowing for the implementation of new logic concepts through interaction with light. This manuscript examines the use of light in implementing new logic concepts as an alternative to traditional logic circuits and as a future technology. This article provides an overview of how to implement logic operations using light rather than voltage or current signals using optoelectronic materials such as 2D materials, metal-oxides, carbon structures, polymers, small molecules, and perovskites. This review covers the various technologies and applications of using light to dope devices, implement logic gates, control logic circuits, and generate light as an output signal. Recent research on logic and the use of light to implement new functions is summarized. This review also highlights the potential of optoelectronic logic for future technological advancements.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38593271

RESUMO

Conventional transistors have long emphasized signal modulation and amplification, often sidelining polarity considerations. However, the recent emergence of negative differential transconductance, characterized by a drain current decline during gate voltage sweeping, has illuminated an unconventional path in transistor technology. This phenomenon promises to simplify the implementation of ternary logic circuits and enhance energy efficiency, especially in multivalued logic applications. Our research has culminated in the development of a sophisticated mixed transconductance transistor (M-T device) founded on a precise Te and IGZO heterojunction. The M-T device exhibits a sequence of intriguing phenomena, zero differential transconductance (ZDT), positive differential transconductance (PDT), and negative differential transconductance (NDT) contingent on applied gate voltage. We clarify its operation using a three-segment equivalent circuit model and validate its viability with IGZO TFT, Te TFT, and Te/IGZO TFT components. In a concluding demonstration, the M-T device interconnected with Te TFT achieves a ternary inverter with an intermediate logic state. Remarkably, this configuration seamlessly transitions into a binary inverter when it is exposed to light.

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