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1.
Biochem Biophys Res Commun ; 691: 149258, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38029541

RESUMO

Mast cells (MCs) possess numerous potent inflammatory mediators and undergo differential regulation in response to antigen (Ag) stimulation. Among the regulatory systems governing secretory responses, soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) play a pivotal role in facilitating granule-plasma membrane fusion and subsequent secretion. Our previous investigation documented the involvement of vesicle-associated membrane protein 3 (VAMP3) in regulating cytokine secretions in RBL-2H3 cells, a model for MC IgE-mediated responses. In addition to VAMP3, VAMP7 is expressed in MCs, but its functional role remains elusive. The present study seeks to explore VAMP7-specific regulatory mechanisms in MCs, shedding light on one of the mechanisms governing heterogeneous secretory responses in these cells. Murine bone marrow-derived mast cells (BMMCs) were examined to analyze the subcellular distribution of inflammatory mediators, specifically TNFα, CCL2, and histamine, and VAMPs (i.e., VAMP3, VAMP7, and VAMP8). Immunocytochemistry and the transient expression of fluorescent protein-conjugated target proteins were used to discern the distribution of various inflammatory mediators and VAMP7 through confocal laser scanning microscopy. Each inflammatory mediator (TNFα, CCL2, and histamine) was found in secretory granules of different sizes within BMMCs. VAMP7 exhibited a distinct distribution compared to VAMP3 in these granules. Notably, an overlapping distribution was observed between VAMP7 and CCL2, but not between VAMP7 and TNFα or VAMP7 and histamine. This suggests that CCL2 resides within VAMP7-expressing granules and is subject to VAMP7-dependent secretory regulation. Consistently, BMMCs with VAMP7 knockdown showed markedly reduced CCL2 secretion after Ag stimulation. These observations underscore the heterogeneity of MC secretory responses and unveil a novel VAMP7-dependent CCL2 secretion mechanism within MCs. This discovery might pave the way for the development of more precise therapeutic strategies to modulate MC secretion in allergic conditions.


Assuntos
Histamina , Mastócitos , Camundongos , Animais , Proteína 3 Associada à Membrana da Vesícula/genética , Proteína 3 Associada à Membrana da Vesícula/metabolismo , Histamina/metabolismo , Mastócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Vesículas Secretórias/metabolismo , Proteínas SNARE/metabolismo
2.
Biol Pharm Bull ; 46(6): 811-816, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37258146

RESUMO

Mast cells (MCs) play an important role in allergies, leading to the development of MC-targeted therapies. Ephedra herb (Mao) has potent anti-allergic activity, but contains ephedrine alkaloids (EAs); therefore, its hazardous effects are taken into consideration during its clinical use. We previously reported that Mao attenuates robust MC degranulation by an allergen through high-affinity immunoglobulin E (IgE) receptor (FcεRI) internalization, in which an EA-independent mechanism was suggested to be at play. This study aimed to deepen our understanding of the potential of Mao against FcεRI internalization using two strains with different EA contents. Mao extracts were administered to bone marrow-derived MCs (BMMCs), and their cellular responses, including FcεRI internalization, were analyzed. In addition, physiological events were evaluated using a passive cutaneous anaphylactic (PCA) reaction mouse model. BMMCs mediate the production of diverse inflammatory mediators. Among these, the potent chemokine CCL2 is thought to be differentially regulated from other pro-inflammatory mediators. We found that Mao significantly induces CCL2 expression in BMMCs despite suppressing robust degranulation through FcεRI internalization. Importantly, this was a distinctly EAs-independent response. In the PCA reaction, local MC activation following allergen challenge was suppressed by Mao treatment, which strengthened the view that Mao sufficiently decreased the rapid activation of MCs and promoted CCL2 secretion. Collectively, these observations provide additional insights into the mechanism of Mao-induced silent FcεRI internalization in MCs and the complex and heterogeneous secretory responses operating in MCs.


Assuntos
Alcaloides , Antineoplásicos , Camundongos , Animais , Receptores de IgE/metabolismo , Efedrina/metabolismo , Degranulação Celular , Mastócitos/metabolismo , Antineoplásicos/farmacologia , Alcaloides/farmacologia , Alérgenos/metabolismo , Mediadores da Inflamação/metabolismo , Imunoglobulinas , Monoaminoxidase/metabolismo , Monoaminoxidase/farmacologia
3.
Environ Geochem Health ; 45(8): 5879-5891, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37179508

RESUMO

Fine atmospheric particles, such as PM2.5, are strongly related to the onset and exacerbation of inflammatory responses leading to the development of respiratory and cardiovascular diseases. PM2.5 is a complex mixture of tiny particles with different properties (i.e., size, morphology, and chemical components). Moreover, the mechanism by which PM2.5 induces inflammatory responses has not been fully elucidated. Therefore, it is necessary to determine the composition of PM2.5 to identify the main factors causing PM2.5-associated inflammation and diseases. In the present study, we investigated PM2.5 from two sites (Fukue, a remote monitoring site, and Kawasaki, an urban monitoring site) with greatly different environments and PM2.5 compositions. The results of ICP-MS and EDX-SEM indicated that PM2.5 from Kawasaki contained more metals and significantly induced the expression of the pro-inflammatory cytokine gene IL-8 compared to the PM2.5 from Fukue. We also verified the increased secretion of IL-8 protein from exposure to PM2.5 from Kawasaki. We further investigated their effects on inflammatory response and cytotoxicity using metal nanoparticles (Cu, Zn, and Ni) and ions and found that the Cu nanoparticles caused a dose-dependent increase in IL-8 expression together with significant cell death. We also found that Cu nanoparticles enhanced the secretion of IL-8 protein. These results suggest that Cu in PM2.5 is involved in lung inflammation.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Material Particulado/toxicidade , Material Particulado/análise , Cobre/toxicidade , Cobre/metabolismo , Citocinas/análise , Citocinas/metabolismo , Citocinas/farmacologia , Células A549 , Interleucina-8/genética , Interleucina-8/metabolismo , Poluentes Atmosféricos/análise , Regulação para Cima , Pulmão
4.
Cell Immunol ; 382: 104632, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36274438

RESUMO

Cysteinyl leukotrienes (CysLTs), released from mast cells (MCs), are important mediators in allergy. Type 1 receptors for CysLTs (CysLT1R) are involved in accelerating IgE-mediated MC activation. In this study, we aimed to elucidate the mechanisms underlying CysLT1R-mediated MC activation. The CysLT1R agonist/antagonist was applied to two types of major MC models-RBL-2H3 cells and bone marrow-derived MCs (BMMCs). The use of CysLT1R and CysLT2R inhibitors revealed that CysLT1R plays a major role in the acceleration of MC activation. The administration of the CysLT1R agonist leukotriene D4 upregulated IgE-mediated Akt and ERK phosphorylation and subsequently enhanced TNF-α expression, suggesting that CysLT1R regulates the downstream pathway of MC activation. However, these observations were not corroborated by CysLT1R knockdown using shRNA, suggesting a differential regulatory mechanism between the temporal and constitutive inhibitions of CysLT. In conclusion, CysLT1R enhances MC activation by accelerating IgE-induced signal transduction, which enables the co-regulation of rapid degranulation and delayed synthesis of inflammatory mediators in MCs.


Assuntos
Leucotrieno D4 , Mastócitos , Leucotrieno D4/metabolismo , Leucotrieno D4/farmacologia , Mastócitos/metabolismo , Receptores de Leucotrienos/genética , Leucotrienos/metabolismo , Imunoglobulina E/metabolismo
5.
Int Arch Allergy Immunol ; 183(4): 453-461, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34847557

RESUMO

BACKGROUND: Allergen-specific desensitization of mast cell (MC) IgE receptors (FcεRI) is an important mechanism of allergen-specific immunotherapy that enables tolerance induction via systemic desensitization. Experimental in vitro IgE-mediated MC desensitization is a potential tool to understand the molecular mechanisms underlying this therapy. Desensitized MCs exhibit internalized IgE and its FcεRI receptors in response to suboptimal doses of allergen without provoking activation. The ovalbumin (OVA) allergen exhibits altered allergenicity upon heat treatment. MC reactions are fundamentally regulated by allergen features (i.e., allergenicity); however, the effects of allergenicity on desensitization remain unclear. OBJECTIVES: This study aimed to examine the impact of allergenicity on the establishment of in vitro MC desensitization using naive OVA (nOVA) and heated OVA (hOVA), which could induce varying MC effector responses. METHOD: Bone marrow-derived MCs (BMMCs) were sensitized with OVA-specific IgE, desensitized with sequentially increasing doses of nOVA or hOVA at 10-min intervals, and challenged with nOVA. To evaluate desensitization, the cell surface expression level and subcellular localization of FcεRI-bound IgE were analyzed before and after the final nOVA challenge. MC activation was determined by measuring the release of ß-hexosaminidase into supernatants. RESULTS: Desensitized cells exhibited impaired activation following OVA challenge. Both nOVA and hOVA induced BMMC desensitization under different conditions. Formation of small IgE-FcεRI cluster BMMCs, which adequately represent the desensitized state, was significant. The size of the internalized IgE-FcεRI clusters might be correlated with the desensitized state of MCs. CONCLUSIONS: We demonstrate that the optimal size of IgE-FcεRI clusters for in vitro BMMC desensitization differed significantly depending on allergenicity, and the efficacy of desensitization was reflected by IgE-FcεRI cluster formation. Our study provides information on the characteristics of IgE-FcεRI internalization for successful desensitization in vitro.


Assuntos
Mastócitos , Receptores de IgE , Alérgenos/metabolismo , Dessensibilização Imunológica , Imunoglobulina E/metabolismo , Receptores de IgE/metabolismo
6.
Pharm Res ; 38(4): 569-581, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33754256

RESUMO

PURPOSE: Ephedra herb (Mao) exerts potent anti-allergic effects. This study aimed to examine the underlying mechanisms of Mao on allergic inflammation using in vitro cultured mast cells (MCs) and an in vivo model of MC-dependent anaphylaxis. METHODS: Bone marrow-derived MCs (BMMCs) were presensitized with anti-2,4-dinitrophenol (DNP) immunoglobulin E (IgE) and challenged with antigens (Ag; DNP-human serum albumin). Degranulation responses and cell surface high-affinity receptor for IgE (FcεRI) expression were assessed with/without Mao treatment. Passive systemic anaphylaxis (PSA)-treated mice were administered Mao and the pathophysiological responses were evaluated. RESULTS: Mao inhibited Ag-induced BMMC degranulation, but not polyclonal activation with phorbol 12-myristate 13-acetate (PMA) and ionomycin, indicating that Mao inhibits IgE-dependent activation of BMMCs. Mao-treated BMMCs exhibited significant reductions in expression of surface IgE and its receptor FcεRI. Analysis of subcellular localization revealed that Mao induces FcεRI internalization in BMMCs without degranulation. In the PSA mouse model, Mao administration prevented antigen-induced hypothermia. Mao administration significantly reduced cell surface expression of IgE-bound FcεRI on peritoneal MCs. CONCLUSIONS: Mao induced FcεRI internalization in MCs, thereby inhibiting Ag-induced IgE-dependent degranulation. The inhibitory effects of Mao on MC degranulation may offer a novel therapeutic approach for allergic diseases.


Assuntos
Anafilaxia/tratamento farmacológico , Antialérgicos/farmacologia , Ephedra/química , Mastócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Anafilaxia/imunologia , Animais , Antialérgicos/uso terapêutico , Degranulação Celular/efeitos dos fármacos , Degranulação Celular/imunologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina E/metabolismo , Ionomicina/imunologia , Mastócitos/imunologia , Medicina Kampo/métodos , Camundongos , Extratos Vegetais/uso terapêutico , Caules de Planta/química , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Acetato de Tetradecanoilforbol/imunologia
7.
Ophthalmic Physiol Opt ; 41(2): 424-430, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33300632

RESUMO

PURPOSE: To determine the frequency, symptoms and risk factors for adverse reactions to two-times instillation of 1% cyclopentolate in children. STUDY DESIGN: Prospective, observational study. METHODS: The subjects were 646 patients who underwent cycloplegic refraction with cyclopentolate (mean age; 7.0 ± 3.5 years, age range; 0-15 years). Five minutes after instillation of 0.4% oxybuprocaine hydrochloride, a 1% cyclopentolate eye drop was instilled twice, with an interval of 10 min. Fifty minutes later, two certified orthoptists evaluated adverse reactions using a questionnaire and interviewed the patients' guardians. The relationship between the adverse reaction rates and age, gender, additional instillation, complications of the central nervous system (CNS), time of day and season were analysed using binominal and polytomous logistic regression models. RESULTS: The overall frequency of adverse reactions was 18.3% (118/646 patients). The main symptoms included conjunctival injection (10.5%, 68/646), drowsiness (6.8%, 44/646) and facial flush (2.2%, 14/646). The odds ratio (OR) of conjunctival injection increased with patient's age (p < 0.05), in boys (p < 0.01) and in winter (p < 0.001). In contrast, the OR of drowsiness decreased with age (p < 0.001). Facial flush was observed mostly in children younger than 4 years. CNS complications were not a significant risk factor for any of the symptoms. CONCLUSIONS: Adverse reactions to 1% cyclopentolate eye drops were more frequent than previously expected, but all were mild and transient. The probability of each symptom was associated with a clear age-specific trend.


Assuntos
Túnica Conjuntiva/efeitos dos fármacos , Doenças da Túnica Conjuntiva/induzido quimicamente , Ciclopentolato/efeitos adversos , Pupila/efeitos dos fármacos , Refração Ocular/fisiologia , Adolescente , Criança , Pré-Escolar , Túnica Conjuntiva/diagnóstico por imagem , Doenças da Túnica Conjuntiva/diagnóstico , Doenças da Túnica Conjuntiva/epidemiologia , Ciclopentolato/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Japão/epidemiologia , Modelos Logísticos , Masculino , Midriáticos/administração & dosagem , Midriáticos/efeitos adversos , Soluções Oftálmicas/efeitos adversos , Prevalência , Estudos Prospectivos , Refração Ocular/efeitos dos fármacos , Fatores de Risco
8.
Biol Pharm Bull ; 43(12): 1945-1949, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33268713

RESUMO

Isoflavones have many biological activities and are major bioactive components of kakkonto, a traditional Japanese herbal medicine. We previously reported that the combined therapy of oral immune therapy (OIT) and kakkonto downregulates the mRNA expression of Cyp26b1, a major retinoic acid (RA)-degrading enzyme, in the colon of food allergy mice and thereby ameliorates allergic symptoms. In this study, we evaluated the effects of various isoflavones on Cyp26b1 expression in primary cultured lamina propria (LP) cells isolated from the mouse colon. The mRNA expression of Cyp26b1 was extremely downregulated by all isoflavones tested in the LP cells except for puerarin. In particular, genistein and genistin markedly suppressed Cyp26b1 mRNA expression without affecting RA-synthesizing enzyme expression. Moreover, to evaluate the effects of isoflavones on allergic reactions, genistein and genistin were administered to ovalbumin (OVA)-induced food allergy mice. Oral administration of genistin suppressed the development of allergic symptoms. These results raise the possibility that isoflavones elevated the level of RA in the colon by inhibiting RA degradation and then the high concentration of RA in the colon might exert immunosuppressive and antiallergic effects on food allergy mice.


Assuntos
Colo/efeitos dos fármacos , Colo/enzimologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/enzimologia , Isoflavonas/farmacologia , Ácido Retinoico 4 Hidroxilase/biossíntese , Animais , Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade Alimentar/enzimologia , Hipersensibilidade Alimentar/etiologia , Regulação Enzimológica da Expressão Gênica , Isoflavonas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Mucosa/efeitos dos fármacos , Mucosa/enzimologia , Ovalbumina/toxicidade , Ácido Retinoico 4 Hidroxilase/antagonistas & inibidores
9.
Respir Investig ; 62(2): 258-261, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38241959

RESUMO

We previously reported that laryngeal widening led to improved exercise tolerance in COPD. However, it is not clear whether laryngeal narrowing occurs as a compensatory response to tracheal movement or is affected by posture. Here, we report the case of an advanced COPD patient whose more prolonged expiration in a head-forward leaning position compared with that in a neck-extended position occurred with an excessive duration of severe laryngeal narrowing without tracheal obstruction, which led to exercise intolerance with expiratory mechanical constraints. This case provided useful insights into the regulation of the upper airway with body positioning for improving exercise tolerance.


Assuntos
Obstrução das Vias Respiratórias , Doença Pulmonar Obstrutiva Crônica , Humanos , Posicionamento do Paciente , Expiração/fisiologia , Obstrução das Vias Respiratórias/etiologia , Traqueia
10.
Open Forum Infect Dis ; 10(1): ofad019, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36726542

RESUMO

Mycobacterium arupense is a slow-growing, nontuberculous mycobacterium widely found in the environment and is known to cause tenosynovitis and osteomyelitis, mainly in the hands and wrists. We present the first case of vertebral osteomyelitis caused by M arupense in a 78-year-old man with renal cell carcinoma. The patient had a history of tuberculous pleuritis in childhood. Although the nucleic acid amplification test of the vertebral tissue for Mycobacterium tuberculosis was negative, we initiated tuberculosis treatment based on the history and pathological findings of auramine-rhodamine-positive organisms and epithelioid cell granulomas. Subsequently, the isolated mycobacterium was identified as M arupense by genome sequencing. Accordingly, the treatment regimen was changed to a combination of clarithromycin, ethambutol, and rifabutin. Owing to a subsequent adverse event, rifabutin was switched to faropenem, and the patient was treated for a total of 1 year. In previous literature, we found 15 reported cases of bone and soft tissue infections caused by M arupense, but none of them had vertebral lesions. Physicians should be aware that M arupense can cause vertebral osteomyelitis mimicking tuberculous spondylitis. In addition, molecular testing of isolated mycobacteria is essential for diagnosis, even if tuberculous spondylitis is suspected.

11.
Front Immunol ; 14: 1154857, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215119

RESUMO

Benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon in the air, triggers pulmonary inflammation. This study focused on BaP-induced inflammation in the alveolar epithelium. A549 cells were stimulated with BaP for four days. BaP treatment markedly increased NLRP1 expression but slightly decreased NLRP3. Furthermore, aryl hydrocarbon receptor (AhR) knockdown displayed no increase in BaP-induced NLRP1 expression. Similar results were also observed by blocking reactive oxygen species (ROS), which is mediated through AhR, suggesting that the AhR-ROS axis operates in BaP-induced NLRP1 expression. p53 involvement in ROS-mediated NLRP1 induction has also been implied. When we confirmed inflammasome activation in cells treated with BaP for four days, while BaP transiently activated NLRP3, it predominantly activated the NLRP1 inflammasome. These findings have led to the conclusion that BaP could be a potential ligand for the NLRP1 inflammasome persistently observed in the lung epithelium. Our study may provide additional evidence for the sustained pulmonary inflammation caused by environmental air pollution.


Assuntos
Benzo(a)pireno , Inflamassomos , Espécies Reativas de Oxigênio/metabolismo , Benzo(a)pireno/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Pulmão/metabolismo
12.
Infect Drug Resist ; 16: 6629-6634, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37840829

RESUMO

Amikacin liposome inhalation suspension (ALIS) is a key drug for the treatment of refractory Mycobacterium avium complex pulmonary disease (MAC-PD). Although cases of drug-induced interstitial lung disease (DIILD) by ALIS have been reported, its diagnosis is challenging due to overlapping existing pulmonary shadows, airway bleeding, exacerbation of underlying conditions, and the potential for various concurrent infections. A 72-year-old woman started treatment with ALIS for refractory MAC-PD. Three weeks later, she had a fever, cough, and appetite loss. She was hospitalized because multiple infiltrative opacities were observed on chest X-ray and chest computed tomography. Because the opacities worsened after empiric antibiotic therapy with broad-spectrum antibiotics, we initiated corticosteroid therapy, suspecting DIILD caused by ALIS, although drug lymphocyte stimulation tests for ALIS and amikacin were negative. Three days later, we found signs of improvement and quickly tapered the corticosteroids. After obtaining informed consent, we performed a drug provocation test of ALIS. Seven days later, she exhibited fever, an increased peripheral white blood cell count, and elevated serum C-reactive protein level, all of which returned to baseline 4 days after stopping ALIS, leading to a diagnosis of DIILD caused by ALIS in this patient. DIILD caused by ALIS is rare but should be carefully diagnosed to ensure that patients with refractory MAC-PD do not miss the opportunity to receive ALIS treatment.

13.
Cells ; 11(4)2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35203273

RESUMO

Mast cells (MCs) perform multiple functions thought to underlie different manifestations of allergies. Various aspects of antigens (Ags) and their interactions with immunoglobulin E (IgE) cause diverse responses in MCs. FcεRI, a high-affinity IgE receptor, deciphers the Ag-IgE interaction and drives allergic responses. FcεRI clustering is essential for signal transduction and, therefore, determines the quality of MC responses. Ag properties precisely regulate FcεRI dynamics, which consequently initiates differential outcomes by switching the intracellular-signaling pathway, suggesting that Ag properties can control MC responses, both qualitatively and quantitatively. Thus, the therapeutic benefits of FcεRI-targeting strategies have long been examined. Disrupting IgE-FcεRI interactions is a potential therapeutic strategy because the binding affinity between IgE and FcεRI is extremely high. Specifically, FcεRI desensitization, due to internalization, is also a potential therapeutic target that is involved in the mechanisms of allergen-specific immunotherapy. Several recent findings have suggested that silent internalization is strongly associated with FcεRI dynamics. A comprehensive understanding of the role of FcεRI may lead to the development of novel therapies for allergies. Here, we review the qualitatively diverse responses of MCs that impact the attenuation/development of allergies with a focus on the role of FcεRI toward Ag exposure.


Assuntos
Hipersensibilidade , Receptores de IgE , Dessensibilização Imunológica , Humanos , Imunoglobulina E/metabolismo , Mastócitos/metabolismo , Receptores de IgE/metabolismo
14.
Medicine (Baltimore) ; 101(33): e30070, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35984202

RESUMO

RATIONALE: Ecthyma gangrenosum (EG) is a potentially life-threatening, systemic infection generally caused by Pseudomonas aeruginosa. Data on EG caused by Staphylococcus aureus in patients with hematological malignancies are scarce. The present case report aimed to describe the clinical features of EG caused by S. aureus in patients with hematological malignancies and to provide a comprehensive review of previous studies on the topic. PATIENT CONCERNS: The first patient was a 61-year-old man with acute myeloid leukemia who presented fever and multiple lesions during chemotherapy. The second patient was a 47-year-old man with myelodysplastic syndrome who developed progressive erythematous necrotic plaques on his extremities and face. DIAGNOSIS: Both cases were diagnosed as EG caused by S. aureus. While the first patient had concurrent methicillin-resistant S. aureus (MRSA) bacteremia, the second patient had positive results only for tissue culture of the skin lesion isolated methicillin-sensitive S. aureus. INTERVENTIONS: Vancomycin was initiated with critical care to the first patient. Cefazolin was administered to the second patient for 3 weeks, followed by cephalexin for 1 week. OUTCOMES: The first patient died of a brain hemorrhage and multiple organ failure. The second patient was cured without relapse. LESSONS: Of 18 patients in the previous and current studies with EG caused by S. aureus, 6 (33%) had an underlying hematological malignancy, and 10 (56%) had EG caused by MRSA. While 28% of the patients had positive blood cultures, all tissue cultures were positive. All 3 fatalities had concurrent bacteremia (MRSA caused two). EG caused by MRSA with concurrent bacteremia can be fatal, especially in patients with hematological malignancies. Although S. aureus-associated EG in patients with hematological malignancies is relatively uncommon, tissue cultures with an initial gram stain smear are essential for selecting appropriate empirical antimicrobials, including the coverage of S. aureus.


Assuntos
Bacteriemia , Ectima , Neoplasias Hematológicas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Ectima/tratamento farmacológico , Ectima/microbiologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/patologia , Staphylococcus aureus
15.
Front Immunol ; 13: 885868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990647

RESUMO

Mast cells (MCs) are inflammatory cells involved in allergic reactions. Crosslinking of the high-affinity receptor for IgE (FcϵRI) with multivalent antigens (Ags) induces secretory responses to release various inflammatory mediators. These responses are largely mediated by soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). Vesicle-associated membrane protein 3 (VAMP3) is a vesicular-SNARE that interacts with targeted SNARE counterparts, driving the fusion of MC secretory granules with the membrane and affecting subsequent assembly of the plasma membrane. However, the role of VAMP3 in FcϵRI-mediated MC function remains unclear. In this study, we comprehensively examined the role of VAMP3 and the molecular mechanisms underlying VAMP3-mediated MC function upon FcϵRI activation. VAMP3 shRNA transduction considerably decreased VAMP3 expression compared with non-target shRNA-transduced (NT) cells. VAMP3 knockdown (KD) cells were sensitized with an anti-DNP IgE antibody and subsequently stimulated with Ag. The VAMP3 KD cells showed decreased degranulation response upon Ag stimulation. Next, we observed intracellular granule formation using CD63-GFP fluorescence. The VAMP3 KD cells were considerably impaired in their capacity to increase the size of granules when compared to NT cells, suggesting that VAMP3 mediates granule fusion and therefore promotes granule exocytosis in MCs. Analysis of FcϵRI-mediated activation of signaling events (FcϵRI, Lyn, Syk, and intracellular Ca2+ response) revealed that signaling molecule activation was enhanced in VAMP3 KD cells. We also found that FcϵRI expression on the cell surface decreased considerably in VAMP3 KD cells, although the amount of total protein did not vary. VAMP3 KD cells also showed dysregulation of plasma membrane homeostasis, such as endocytosis and lipid raft formation. The difference in the plasma membrane environment in VAMP3 KD cells might affect FcϵRI membrane dynamics and the subsequent signalosome formation. Furthermore, IgE/Ag-mediated secretion of TNF-α and IL-6 is oppositely regulated in the absence of VAMP3, which appears to be attributed to both the activation of FcϵRI and defects in VAMP3-mediated membrane fusion. Taken together, these results suggest that enhanced FcϵRI-mediated signal transduction in VAMP3 KD cells occurs due to the disruption of plasma membrane homeostasis. Hence, a multifunctional regulation of VAMP3 is involved in complex secretory responses in MCs.


Assuntos
Exocitose , Receptores de IgE , Imunoglobulina E , RNA Interferente Pequeno , Receptores de IgE/metabolismo , Proteínas SNARE , Proteína 3 Associada à Membrana da Vesícula/genética , Proteína 3 Associada à Membrana da Vesícula/metabolismo
16.
Chem Asian J ; 17(4): e202101341, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-34939334

RESUMO

During the self-assembly of π-conjugated molecules, linkers and substituents can potentially add supportive noncovalent intermolecular interactions to π-stacking interactions. Here, we report the self-assembly behavior of thienopyrrole-fused thiadiazole (TPT) fluorescent dyes that possess ester or ether linkers and dodecyloxy side chains in solution and the condensed phase. A comparison of the self-association behavior of the ester- and ether-bridged compounds in solution using detailed UV-vis, fluorescence, and NMR spectroscopic studies revealed that the subtle replacement of the ether linkers by ester linkers leads to a distinct increase in the association constant (ca. 3-4 fold) and the enthalpic contribution (ca. 3 kcal mol-1 ). Theoretical calculations suggest that the ester linkers, which are in close proximity to one another due to the π-stacking interactions, induce attractive electrostatic forces and augment self-association. The self-assembly of TPT dyes into well-defined 1D clusters with high aspect ratios was observed, and their morphologies and crystallinity were investigated using SEM and X-ray diffraction analyses. TPTs with ester linkers exhibit a columnar liquid crystalline mesophase in the condensed phase.


Assuntos
Tiadiazóis , Ésteres , Éter , Éteres , Pirróis , Eletricidade Estática
17.
J Nutr Sci Vitaminol (Tokyo) ; 66(5): 462-467, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132350

RESUMO

Aldehyde dehydrogenase 1A1 (ALDH1A1) in intestinal epithelial cells (IECs) plays a critical role in regulating immune responses through the production of retinoic acid (RA). However, little is known about its regulation by dietary components. We previously demonstrated that kakkonto, a Japanese traditional herbal medicine, and its constituent puerarin induce the expression of ALDH1A1 mRNA in colonic IECs and thereby attenuate food allergy symptoms in mice. This study aims to investigate the cellular responses of IECs to ALDH1A1 expression as a result of natural food components. The seven medicinal herbs that compose kakkonto were used to treat cultured an IEC line: Caco-2 cells. Expressions levels of ALDH1A1 were analyzed in Caco-2 cells by quantitative RT-PCR, immunocytochemistry and western blotting. Ginger increased the expression levels of ALDH1A1 mRNA and protein in Caco-2 cells. In addition, ginger significantly upregulated the gene expression of retinoic acid receptor (RAR) alpha (RARA), thereby enhancing RA signaling. Furthermore, ginger downregulated the expression of histone deacetylase (HDAC)2 (HDAC2) and HDAC3 in Caco-2 cells. The present study suggests the possibility that food ingredients such as a ginger modulate vitamin A metabolism in the gut through the regulation of RA synthesis, which may contribute to RA-mediated regulation of immune responses and the regulation of allergic inflammation.


Assuntos
Família Aldeído Desidrogenase 1 , Retinal Desidrogenase , Tretinoína , Zingiber officinale , Aldeído Desidrogenase , Família Aldeído Desidrogenase 1/metabolismo , Animais , Células CACO-2 , Células Epiteliais , Humanos , Camundongos , Retinal Desidrogenase/metabolismo
18.
Sci Adv ; 6(25): eaax7236, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32596439

RESUMO

An all-solid-state lithium battery using inorganic solid electrolytes requires safety assurance and improved energy density, both of which are issues in large-scale applications of lithium-ion batteries. Utilization of high-capacity lithium-excess electrode materials is effective for the further increase in energy density. However, they have never been applied to all-solid-state batteries. Operational difficulty of all-solid-state batteries using them generally lies in the construction of the electrode-electrolyte interface. By the amorphization of Li2RuO3 as a lithium-excess model material with Li2SO4, here, we have first demonstrated a reversible oxygen redox reaction in all-solid-state batteries. Amorphous nature of the Li2RuO3-Li2SO4 matrix enables inclusion of active material with high conductivity and ductility for achieving favorable interfaces with charge transfer capabilities, leading to the stable operation of all-solid-state batteries.

19.
Front Immunol ; 10: 1933, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507589

RESUMO

The prevalence of food allergy has been steadily rising worldwide with the highest incidence noted among younger children, and increasingly recognized as a growing public concern. The first known ingestion of foods often causes allergic reaction, suggesting that sensitization of offspring with food allergens may occur during pregnancy and/or through breastfeeding. This creates a milieu that shapes the neonatal immune responses to these allergens. However, the effects of maternal allergen exposure and maternal sensitization with allergens on development of allergies in offspring remain controversial. This review discusses recent advances from human data in our understanding of how maternal factors, namely, food allergens, allergen-specific immunoglobulins, cytokines, genetics, and environmental factors transferred during pregnancy or breastfeeding influence offspring allergies and how such effects may be applicable to food allergy. Based on information obtained from mouse models of asthma and food allergy, the review also dissects the mechanisms by which maternal factors, including the impact of immune complexes, transforming growth factor-ß, vitamin A, and regulatory T-cell responses, contribute to the induction of neonatal tolerance vs. development of allergic responses to maternally transferred allergens.


Assuntos
Hipersensibilidade Alimentar/imunologia , Alérgenos/imunologia , Animais , Aleitamento Materno/efeitos adversos , Citocinas/imunologia , Feminino , Humanos , Exposição Materna , Gravidez , Linfócitos T Reguladores/imunologia
20.
ACS Appl Mater Interfaces ; 10(23): 19605-19614, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29775274

RESUMO

All-solid-state sodium batteries using Na3Zr2Si2PO12 (NASICON) solid electrolytes are promising candidates for safe and low-cost advanced rechargeable battery systems. Although NASICON electrolytes have intrinsically high sodium-ion conductivities, their high sintering temperatures interfere with the immediate development of high-performance batteries. In this work, sintering-free NASICON-based composites with Na3PS4 (NPS) glass ceramics were prepared to combine the high grain-bulk conductivity of NASICON and the interfacial formation ability of NPS. Before the composite preparation, the NASICON/NPS interfacial resistance was investigated by modeling the interface between the NASICON sintered ceramic and the NPS glass thin film. The interfacial ion-transfer resistance was very small above room temperature; the area-specific resistances at 25 and 100 °C were 15.8 and 0.40 Ω cm2, respectively. On the basis of this smooth ion transfer, NASICON-rich (70-90 wt %) NASICON-NPS composite powders were prepared by ball-milling fine powders of each component. The composite powders were well-densified by pressing at room temperature. Scanning electron microscopy observation showed highly dispersed sub-micrometer NASICON grains in a dense NPS matrix to form closed interfaces between the oxide and sulfide solid electrolytes. The composite green (unfired) compacts with 70 and 80 wt % NASICON exhibited high total conductivities at 100 °C of 1.1 × 10-3 and 6.8 × 10-4 S cm-1, respectively. An all-solid-state Na15Sn4/TiS2 cell was constructed using the 70 wt % NASICON composite electrolyte by the uniaxial pressing of the powder materials, and its discharge properties were evaluated at 100 °C. The cell showed the reversible capacities of about 120 mAh g-1 under the current density of 640 µA cm-2. The prepared oxide-based composite electrolytes were thus successfully applied in all-solid-state sodium rechargeable batteries without sintering.

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