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1.
Genes Cells ; 27(5): 345-355, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35194900

RESUMO

GPR85 is a member of the G protein-coupled receptor and is a super-conserved receptor expressed in the brain sub-family (Super Conserved Receptor Expressed in Brain; SREB) with GPR27 and GPR173. These three receptors are "orphan receptors"; however, their endogenous ligands have not been identified. SREB has garnered the interest of many scientists because it is expressed in the central nervous system and is evolutionarily conserved. In particular, brain mass is reported to be increased and learning and memory are improved in GPR85 knockout mice (Matsumoto et al. 2008). In this study, we characterized newly synthesized compounds using a GPR85-Gsα fusion protein and the [35 S]GTPγS binding assay and identified novel GPR85 inverse-agonists with IC50 values of approximately 1 µM. To analyze the neurochemical character of the compounds and investigate the physiological significance of GPR85, we used cerebellar Purkinje cells expressing GPR85 and an electrophysiological technique. Based on the results, the inverse-agonist compound for GPR85 modulated potassium channel opening. Together with the results of previous gene analysis of GPR85, we expect that the development of the GPR85 ligand will provide new insights into a few types of neurological disorders.


Assuntos
Encéfalo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Encéfalo/metabolismo , Sistema Nervoso Central , Aprendizagem , Ligantes , Camundongos , Receptores Acoplados a Proteínas G/genética
2.
Sensors (Basel) ; 23(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36991988

RESUMO

This paper presents a feasibility study on monitoring earthquake-caused furniture vibrations using radiofrequency identification (RFID) sensor tags. Finding unstable objects by exploiting the vibrations caused by weaker earthquakes is effective as one of the potential countermeasures for large-scale earthquakes in earthquake-prone areas. For this purpose, a previously proposed ultrahigh-frequency (UHF)-band RFID-based batteryless vibration/physical shock sensing system enabled long-term monitoring. This RFID sensor system introduced standby and active modes for long-term monitoring. This system enabled lower-cost wireless vibration measurements without affecting the vibration of furniture because the RFID-based sensor tags provide lightweight, low-cost, and battery-free operations. This RFID sensor system observed earthquake-cased furniture vibrations in a room on the fourth floor of a building eight stories high at Ibaraki University, Hitachi, Ibaraki, Japan. The observation results revealed that the RFID sensor tags identified the vibrations of furniture caused by earthquakes. The RFID sensor system also observed the vibration duration times of the objects in a room and specified the most unstable reference object. Hence, the proposed vibration sensing system helped achieve safe living in indoor environments.

3.
Cancer Immunol Immunother ; 71(4): 851-863, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34463793

RESUMO

Cancer immunotherapy using immune checkpoint inhibitors (ICIs) has been recognized as a novel therapeutic option for head and neck squamous cell carcinoma (HNSCC). However, only approximately 20-30% of patients with recurrent/metastatic (R/M) HNSCC benefit. Moreover, the mechanisms underlying the response to ICIs remain unclear. We investigated the proportion, activation status, and expression level of immune checkpoint molecules in circulating T cell subsets in R/M HNSCC patients treated with nivolumab using flow cytometry and mass cytometry, and then determined whether treatment response was associated with these values. We also assessed the changes in the frequency of tumor-associated antigens, MAGE-A4 and p53, -specific T cells prior to and after nivolumab treatment using the IFN-γ ELISPOT assay. The proportion of activated CD4+ and CD8+ TEMRA cells significantly increased in the disease-controlled patients but not in disease-progressed patients. As expected, the expression of PD-1 in T cells markedly decreased regardless of the therapeutic response. Meanwhile, T cell immunoglobulin mucin-3 expression on CD8+ T cells was significantly higher in patients with disease progression than in disease-controlled patients after treatment. The frequency of the tumor-associated antigens, MAGE-A4- and p53-specific T cells, was not correlated with clinical responses; however, in the disease-controlled patients, the frequency of MAGE-A4-specific T cells was significantly augmented. We concluded that in R/M HNSCC patients treated with nivolumab, circulating T cells show dynamic alterations depending on treatment efficacy. An analysis of the immunokinetics of circulating T cells could thus provide new insights into rational therapeutic strategies in cancer immunotherapy for HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Nivolumabe , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Nivolumabe/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Subpopulações de Linfócitos T
4.
Curr Microbiol ; 78(4): 1267-1276, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33638001

RESUMO

The bacterium Staphylococcus aureus, which colonizes healthy human skin, may cause diseases, such as atopic dermatitis (AD). Treatment for such AD cases involves antibiotic use; however, alternate treatments are preferred owing to the development of antimicrobial resistance. This study aimed to characterize the novel bacteriophage SaGU1 as a potential agent for phage therapy to treat S. aureus infections. SaGU1 that infects S. aureus strains previously isolated from the skin of patients with AD was screened from sewage samples in Gifu, Japan. Its genome was sequenced and analyzed using bioinformatics tools, and the morphology, lytic activity, stability, and host range of the phage were determined. The SaGU1 genome was 140,909 bp with an average GC content of 30.2%. The viral chromosome contained 225 putative protein-coding genes and four tRNA genes, carrying neither toxic nor antibiotic resistance genes. Electron microscopy analysis revealed that SaGU1 belongs to the Myoviridae family. Stability tests showed that SaGU1 was heat-stable under physiological and acidic conditions. Host range testing revealed that SaGU1 can infect a broad range of S. aureus clinical isolates present on the skin of AD patients, whereas it did not kill strains of Staphylococcus epidermidis, which are symbiotic resident bacteria on human skin. Hence, our data suggest that SaGU1 is a potential candidate for developing a phage therapy to treat AD caused by pathogenic S. aureus.


Assuntos
Dermatite Atópica , Staphylococcus aureus , Genoma Viral , Humanos , Japão , Fagos de Staphylococcus/genética , Staphylococcus aureus/genética
5.
J Mater Sci Mater Med ; 32(6): 58, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33999320

RESUMO

The evaluation of antitumor immune responses is essential for immune monitoring to predict clinical outcomes as well as treatment efficacies in cancer patients. In this study, we produced two tumor antigen (TA) proteins, melanoma antigen family A4 and wild type p53, using TG silkworm systems and evaluated anti-TA-specific immune responses by enzyme-linked immunosorbent spot assays in patients with head and neck cancer. Eleven (61.1%) of 18 patients showed significant IFN-γ production in response to at least one TA; however, the presence of TA-specific immune responses did not significantly contribute to better prognosis (overall survival, p = 0.1768; progression-free survival, p = 0.4507). Further studies will need to be performed on a larger scale to better assess the clinical significance of these systems. The production of multiple TA proteins may provide new avenues for the development of immunotherapeutic strategies to stimulate a potent and specific immune response against tumor cells as well as precise assessment of antitumor immune responses in cancer patients.


Assuntos
Antígenos de Neoplasias/química , Neoplasias de Cabeça e Pescoço/imunologia , Sistema Imunitário , Imunoterapia/métodos , Adulto , Idoso , Animais , Animais Geneticamente Modificados , Antígenos de Neoplasias/biossíntese , Bombyx , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Imunidade , Imuno-Histoquímica , Técnicas In Vitro , Estimativa de Kaplan-Meier , Leucócitos Mononucleares/citologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Intervalo Livre de Progressão , Proteína Supressora de Tumor p53/biossíntese
6.
Protein Expr Purif ; 176: 105723, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32768455

RESUMO

Silkworms are economically important insects that have the ability to produce large amounts of silk. They have mass breeding methods and silk glands, which are specialized tissues that secrete silk fibroin and sericin. Thus, the production of recombinant proteins in a transgenic silkworm system is a promising approach. We developed a silkworm, Bombyx mori, as a host expression insect for recombinant proteins and successfully produced different proteins including antibodies, glycoproteins, and membrane receptors. The thyroid hormone receptor (TR) is a regulatory factor for many physiological phenomena. It is a lipophilic protein that has DNA-binding and ligand-binding domains. Based on our previous experiences, it was inferred that the recombinant TR easily formed aggregates and precipitates which is potentially due to an unstructured hinge domain. We applied the silkworm expression system to produce mice TRß1 that was fused with glutathione S-transferase. Using 160 larvae, the yield of the recombinant GST-TRß was approximately 4 mg, and the purified GST-TRß completely retained its physiological activity. Our results indicated that the recombinant TRß was secreted extracellularly using the silk fibroin signal peptide sequence. Moreover, we found that the expression system of silkworms was applicable to nuclear proteins.


Assuntos
Animais Geneticamente Modificados , Bombyx , Receptores beta dos Hormônios Tireóideos , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Bombyx/genética , Bombyx/metabolismo , DNA/química , DNA/metabolismo , Camundongos , Ligação Proteica , Receptores beta dos Hormônios Tireóideos/biossíntese , Receptores beta dos Hormônios Tireóideos/química , Receptores beta dos Hormônios Tireóideos/genética , Receptores beta dos Hormônios Tireóideos/isolamento & purificação
7.
Biosci Biotechnol Biochem ; 84(12): 2484-2490, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32867616

RESUMO

Discovery of small-molecule inducers of unique phenotypic changes combined with subsequent target identification often provides new insights into cellular functions. Here, we applied integrated profiling based on cellular morphological and proteomic changes to compound screening. We identified an indane derivative, NPD9055, which is mechanistically distinct from reference compounds with known modes of action. Employing a chemical proteomics approach, we then showed that NPD9055 binds subunits of heterotrimeric G-protein Gi. An in vitro [35S]GTPγS-binding assay revealed that NPD9055 inhibited GDP/GTP exchange on a Gαi subunit induced by a G-protein-coupled receptor agonist, but not on another G-protein from the Gαs family. In intact HeLa cells, NPD9055 induced an increase in intracellular Ca2+ levels and ERK/MAPK phosphorylation, both of which are regulated by Gßγ, following its dissociation from Gαi. Our observations suggest that NPD9055 targets Gαi and thus regulates Gßγ-dependent cellular processes, most likely by causing the dissociation of Gßγ from Gαi.


Assuntos
Descoberta de Drogas , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Fenótipo , Proteômica , Bibliotecas de Moléculas Pequenas/farmacologia , Linhagem Celular Tumoral , Humanos
8.
Neuropathology ; 40(5): 501-506, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32677221

RESUMO

We report a 50-year-old man who developed fatal brainstem infarction five days after traumatic cervical vertebral artery dissection (CVAD). Autopsy revealed multiple fresh infarcts in the territory of the vertebrobasilar system. No thrombus was found in the infarct lesions. The cervical vertebral artery (CVA) showed severe atherosclerotic stenosis extending to the proximal half of the left side, similar stenosis at the origin on the right side, fresh thrombotic occlusion extending to the proximal half of the right side, and multiple dissections in the distal foraminal segments on both sides. In the distal half of the basilar artery (BA) and the origin of the right posterior cerebral artery (PCA), the lumen was extensively filled with fresh thrombus. Although an intricate mixture of white and red thrombi filled the lumen at the origin of the right PCA, the white thrombus gradually appeared at the periphery whereas the red thrombus occupied the central and more proximal part of the BA. We confirm that cerebral infarction associated with CVAD is due not only to emboli originating from the dislodged thrombus at sites of arterial dissection, as reported previously, but also to newly formed thrombus in the cerebral arteries caused by impaired blood flow, as was seen in the present case.


Assuntos
Infarto Cerebral/patologia , Trombose Intracraniana/patologia , Procedimentos Neurocirúrgicos/efeitos adversos , Dissecação da Artéria Vertebral/patologia , Infarto Cerebral/etiologia , Vértebras Cervicais/patologia , Humanos , Trombose Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Dissecação da Artéria Vertebral/etiologia
9.
Genes Cells ; 23(7): 528-536, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29767456

RESUMO

Tailed bacteriophages (Caudovirales) are divided into three families: Myoviridae with long contractile tails, Siphoviridae with long noncontractile tails and Podoviridae with short noncontractile tails. All have an icosahedral head with a portal vertex connected to a neck structure followed by a tail. Bacteriophage Mu belongs to the Myoviridae family. Herein, the gp29 portal subunit and neck subunits gp35, gp36 and gp37 of the Mu phage were purified to elucidate their arrangement in the neck. Both gp29 and gp36 were monomeric in solution, like the corresponding subunits of Podoviridae P22 and Siphoviridae SPP1. X-ray crystal structure of gp36 showed structural similarity to neck subunits of Siphoviridae and Podoviridae. The gp36 structure has a characteristic aromatic hydrophobic core, and the structure of the ring form of the Mu phage connector deduced from the Siphoviridae and Podoviridae connector showed that this feature builds the contact surface between gp36 subunits. Structural comparison with the neck of Siphoviridae and Podoviridae also implies direct interaction between gp36 and gp29. Because gp35 and gp36 form a stable complex, we predict that the head-portal ring (gp29), the connector complex (gp36 and gp35), the tail terminator (gp37) and the tube (gp40) are arranged in the Mu phage neck in this order.


Assuntos
Myoviridae/ultraestrutura , Podoviridae/ultraestrutura , Siphoviridae/ultraestrutura , Bacteriófagos/fisiologia , Caudovirales/fisiologia , Caudovirales/ultraestrutura , Cristalografia por Raios X/métodos , DNA Viral , Genoma Viral , Myoviridae/fisiologia , Podoviridae/fisiologia , Conformação Proteica , Siphoviridae/fisiologia
10.
Neuropathology ; 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29876971

RESUMO

Neuropathological examinations of the brain in cases of brain death are usually insufficient because of autolysis. We examined a case of sporadic-type cerebral amyloid angiopathy-related hemorrhage (sCAA-H) in a 74-year-old Japanese woman who had been clinically established as brain dead 7 days before cardiac arrest. The brain was macerated, and a huge hematoma was evident in the right parieto-occipital region. Ordinary neuropathological examination was unable to clarify where the hematoma was located in the brain parenchyma or the subarachnoid space (SAS). Immunohistochemistry for amyloid-ß (Aß) and synaptophysin revealed that: (i) the hematoma affected the cerebral sulcus, cerebral cortex (CC) and subcortical white matter; (ii) the CC was destroyed at the depth of the cerebral sulcus; (iii) in three 6-µm-thick sections, ruptured Aß-positive vessels were seen only in the intrasulcal hematoma and not in the CC or intracerebral hematoma; and (iv) in the CC adjacent to the intrasulcal hematoma, a few macrophages were observed, indicating a fresh infarct of the CC. These findings indicate that sCAA-H occurred first in the cerebral sulcus due to rupture of multiple meningeal vessels, as had been documented in our previous reports. The present study shows that even in an autolytic dead brain, immunohistochemistry is more useful than ordinary staining methods. Other than double-barreled vessels, several vascular changes such as fibrinoid degeneration, segmental dilatation (so-called micro-aneurysmal dilatation), and hyalinous onion-like change of the intima were seen in the intrasulcal hematoma, SAS and CC. Interestingly these vascular changes were not observed in the ruptured Aß-positive vessels. More detailed studies will be needed to examine the correlation between these vascular changes and vessel rupture.

11.
Genes Cells ; 21(7): 717-27, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27184081

RESUMO

The identification of novel synthetic ligands for G protein-coupled receptors (GPCRs) is important not only for understanding human physiology, but also for the development of novel drugs, especially for orphan GPCRs for which endogenous ligands are unknown. One of the orphan GPCR subfamilies, Super conserved Receptor Expressed in Brain (SREB), consists of GPR27, GPR85 and GPR173 and is expressed in the central nervous system. We report herein the identification of inverse agonists for the SREB family without their agonists. We carried out an in vitro screening of 5472 chemical compounds from the RIKEN NPDepo chemical library. The binding of [(35) S]GTPγS to the GPR173-Gsα fusion protein expressed in Sf9 cells was measured and resulted in the identification of 8 novel GPR173 inverse agonists. The most potent compound showed an IC50 of approximately 8 µm. The identified compounds were also antagonists for other SREB members, GPR27 and GPR85. These results indicated that the SREB family could couple Gs-type G proteins, and SREB-Gsα fusion proteins showed significant constitutive activities. Moreover, a molecular model of GPR173 was constructed using the screening results. The combination of computational and biological methods will provide a unique approach to ligand identification for orphan GPCRs and brain research.


Assuntos
Simulação de Acoplamento Molecular/métodos , Proteínas do Tecido Nervoso/química , Receptores Acoplados a Proteínas G/química , Bibliotecas de Moléculas Pequenas/química , Encéfalo/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Expressão Gênica , Humanos , Ligantes , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/genética , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/genética , Interface Usuário-Computador
12.
Neuropathology ; 37(6): 502-508, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28836300

RESUMO

To clarify the frequency of CAA in the brain parenchyma and subarachnoid space (SAS), we counted sections of blood vessels showing positive staining for Aß in the SAS, cerebral cortex (CC) and cerebral white matter (WM) using paraffin-embedded sections of the frontal, temporal and occipital lobes. The specimens had been taken for routine neuropathological examination from the brains of 105 Japanese patients (aged 40-95 years) selected from among 200 consecutive patients autopsied between 1989 and 2015 at our hospital. We examined the anatomical ratios of blood-vessel sections in the SAS relative to the CC in three selected CAA cases, and those of Aß-positive blood-vessel sections in CAA cases. CAA was found in 53 of the 105 cases (50.5%), and the youngest patient affected was a 51-year-old man. The incidence of CAA increased with age. The anatomical ratio of blood vessel sections in the SAS relative to the CC was 1/3.70-1/4.37 (mean: 1/3.94). The ordinary CAA group, in which CAA was seen in both the SAS and CC, included 41 cases (77.4%). In 37 of these cases, the SAS/CC ratio of Aß-positive blood vessels was 1/0.05-1/0.66 (mean: 1/0.26), and in the other four cases the ratio was 1/1-1/1.5. In the ordinary CAA group, the SAS/CC ratio of Aß-positive blood vessels was smaller than the anatomical ratio. The meningeal CAA group, in which CAA was found only in the SAS, included 12 cases (22.6%). These patients ranged in age from their fifties to their nineties. There was no case in which CAA was limited only to the CC. We concluded that CAA initially develops in the meningeal blood vessels, and not in the cortical blood vessels. CAA in the WM was seen in 10 cases, not only in nine cases that were severe, but also in a mild case.


Assuntos
Vasos Sanguíneos/patologia , Encéfalo/patologia , Angiopatia Amiloide Cerebral/patologia , Meninges/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espaço Subaracnóideo/patologia
13.
Brain ; 137(Pt 2): 520-36, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24271323

RESUMO

The aim of this study was to elucidate the characteristics, pathogenesis and treatment strategy of hypertrophic pachymeningitis that is associated with myeloperoxidase anti-neutrophil cytoplasmic antibody (ANCA). We retrospectively investigated clinical, radiological, immunological and pathological profiles of 36 patients with immune-mediated or idiopathic hypertrophic pachymeningitis, including 17 patients with myeloperoxidase-ANCA, four patients with proteinase 3-ANCA, six patients with other immune-mediated disorders, and nine patients with 'idiopathic' variety. Myeloperoxidase-ANCA-positive hypertrophic pachymeningitis was characterized by: (i) an elderly female predominance; (ii) 82% of patients diagnosed with granulomatosis with polyangiitis (previously known as Wegener's granulomatosis) according to Watts' algorithm; (iii) a high frequency of patients with lesions limited to the dura mater and upper airways, developing headaches, chronic sinusitis, otitis media or mastoiditis; (iv) a low frequency of patients with the 'classical or generalized form' of granulomatosis with polyangiitis involving the entire upper and lower airways and kidney, or progressing to generalized disease, in contrast to proteinase 3-ANCA-positive hypertrophic pachymeningitis; (v) less severe neurological damage according to the modified Rankin Scale and low disease activity according to the Birmingham Vasculitis Activity Score compared with proteinase 3-ANCA-positive hypertrophic pachymeningitis; (vi) increased levels of CXCL10, CXCL8 and interleukin 6 in cerebrospinal fluids, and increased numbers of T cells, neutrophils, eosinophils, plasma cells and monocytes/macrophages in autopsied or biopsied dura mater with pachymeningitis, suggesting TH1-predominant granulomatous lesions in hypertrophic pachymeningitis, as previously reported in pulmonary or renal lesions of granulomatosis with polyangiitis; and (vii) greater efficacy of combination therapy with prednisolone and cyclophosphamide compared with monotherapy with prednisolone. Proteinase 3-ANCA may be considered a marker for more severe neurological damage, higher disease activity and a higher frequency of the generalized form compared with myeloperoxidase-ANCA-positive hypertrophic pachymeningitis. However, categorization into 'granulomatosis with polyangiitis' according to Watts' algorithm and immunological or pathological features were common in both proteinase 3- and myeloperoxidase-ANCA-positive hypertrophic pachymeningitis. These data indicate that most patients with myeloperoxidase-ANCA-positive hypertrophic pachymeningitis should be categorized as having the central nervous system-limited form of ANCA-associated vasculitis, consistent with the concept of ophthalmic-, pulmonary- or renal-limited vasculitis.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Anticorpos Anticitoplasma de Neutrófilos/líquido cefalorraquidiano , Hipertrofia/sangue , Hipertrofia/líquido cefalorraquidiano , Meningite/sangue , Meningite/líquido cefalorraquidiano , Peroxidase/sangue , Peroxidase/líquido cefalorraquidiano , Vasculite/enzimologia , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Feminino , Humanos , Hipertrofia/enzimologia , Masculino , Meningite/enzimologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Vasculite/sangue , Vasculite/líquido cefalorraquidiano
14.
Biochim Biophys Acta ; 1834(1): 284-91, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22922659

RESUMO

Bacteriophage Mu, which has a contractile tail, is one of the most famous genus of Myoviridae. It has a wide host range and is thought to contribute to horizontal gene transfer. The Myoviridae infection process is initiated by adhesion to the host surface. The phage then penetrates the host cell membrane using its tail to inject its genetic material into the host. In this penetration process, Myoviridae phages are proposed to puncture the membrane of the host cell using a central spike located beneath its baseplate. The central spike of the Mu phage is thought to be composed of gene 45 product (gp45), which has a significant sequence homology with the central spike of P2 phage (gpV). We determined the crystal structure of shortened Mu gp45Δ1-91 (Arg92-Gln197) at 1.5Å resolution and showed that Mu gp45 is a needlelike structure that punctures the membrane. The apex of Mu gp45 and that of P2 gpV contained iron, chloride, and calcium ions. Although the C-terminal domain of Mu gp45 was sufficient for binding to the E. coli membrane, a mutant D188A, in which the Asp amino acid residue that coordinates the calcium ion was replaced by Ala, did not exhibit a propensity to bind to the membrane. Therefore, we concluded that calcium ion played an important role in interaction with the host cell membrane.


Assuntos
Bacteriófago mu/química , Proteínas do Envelope Viral/química , Bacteriófago mu/metabolismo , Cálcio/química , Cálcio/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Membrana Celular/virologia , Cristalografia por Raios X , Escherichia coli/química , Escherichia coli/metabolismo , Escherichia coli/virologia , Estrutura Terciária de Proteína , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus
15.
Neuropathol Appl Neurobiol ; 40(5): 551-63, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23659519

RESUMO

AIMS: Mutations in the SCARB2 gene cause a rare autosomal recessive disease, progressive myoclonus epilepsy (PME) with or without renal failure, the former also being designated action myoclonus-renal failure syndrome. Although reported cases have been accumulating, only a few have described its neuropathology. We studied two Japanese patients with PME without renal failure, in whom the ages at onset and disease durations were 45 and 20 years, and 14 and 8.5 years respectively. METHODS: Sequencing and restriction analysis of the SCARB2 gene and neuropathological examination with immunohistochemistry were performed. RESULTS: Gene analyses revealed novel homozygous frameshift and nonsense mutations in the SCARB2 gene. Both cases exhibited deposition of brown pigment in the brain, especially the cerebellar and cerebral cortices. Ultrastructurally, the pigment granules were localized in astrocytes. Neuronal loss and gliosis were also evident in the brain, including the pallidoluysian and cerebello-olivary systems. The spinal cord was also affected. Such changes were less severe in one patient with late-onset disease than in the other patient with early-onset disease. In brain and kidney sections, immunostaining with an antibody against the C-terminus of human SCARB2 revealed decreased levels and no expression of the protein respectively. CONCLUSIONS: The frameshift mutation detected in the patient with late-onset disease is a hitherto undescribed, unique type of SCARB2 gene mutation. The present two patients are the first reported to have clearly demonstrated both extraneuronal brown pigment deposition and system neurodegeneration as neuropathological features of PME with SCARB2 mutations.


Assuntos
Astrócitos/ultraestrutura , Encéfalo/ultraestrutura , Proteínas de Membrana Lisossomal/genética , Mutação , Epilepsias Mioclônicas Progressivas/genética , Epilepsias Mioclônicas Progressivas/patologia , Células de Purkinje/ultraestrutura , Receptores Depuradores/genética , Adulto , Povo Asiático , Códon sem Sentido , Feminino , Mutação da Fase de Leitura , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Linhagem , Adulto Jovem
16.
Virology ; 593: 110017, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38382161

RESUMO

Bacteriophage Mu is a temperate phage known to infect various species of Enterobacteria, playing a role in bacterial mutation induction and horizontal gene transfer. The phage possesses two types of tail fibers important for host recognition, which enable it to expand its range of hosts. The alternate tail fibers are formed through the action of genes 49-50 or 52-51, allowing the Mu phage to recognize different surfaces of host cells. In a previous study, we presented the X-ray crystal structure of the C-terminal lipopolysaccharide (LPS)-binding domain of gene product (gp) 49, one of the subunits comprising the Mu tail fiber. In this study, we have determined the structure of the alternative tail fiber subunit, gp52, and compared it with other tail fibers. The results revealed that Mu phage employs different structural motifs for two individual tail fibers for recognizing different hosts.


Assuntos
Bacteriófago mu , Bacteriófagos , Bacteriófago mu/química , Bacteriófago mu/genética , Bacteriófagos/genética , Proteínas da Cauda Viral/genética
17.
Anticancer Res ; 44(7): 2921-2931, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38925841

RESUMO

BACKGROUND/AIM: Human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) is clinically and immunologically distinct from HPV-negative HNSCC. Herein, we investigated the presence of tumor antigens HPV E6/E7 and wild-type p53-specific T-cell responses, and the impact of immune checkpoint blockade in patients with HPV-positive HNSCC. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMCs) from patients with HPV-positive HNSCC were stimulated with HPV E6/E7 or wild-type p53-derived peptide mixture and evaluated using the interferon-γ enzyme-linked immunosorbent spot assay. Flow cytometry was performed to analyze the proportion of T-cell subsets and T cells expressing immune checkpoint molecules. RESULTS: HPV E6/E7-specific T cells were detected in 22 (95.7%) of 23 patients, whereas wild-type p53-specific T cells were detected in 3 (15.0%) of 20 patients. Seven (43.8%) of 16 patients exhibited wild-type p53-specific T-cell responses, as determined using whole proteins instead of peptides. Immune checkpoint blockade enhanced wild-type p53-specific T-cell responses in 9 (45.0%) of 20 patients. Flow cytometric analysis of PBMCs revealed that responders exhibiting enhanced wild-type p53-specific T-cell responses following immune checkpoint blockade had a significantly higher proportion of Ki-67+CD4+ T cells, Ki-67+CD8+ T cells, regulatory T cells, PD-1+CD4+ T cells, and TIM-3+CD4+ T cells than non-responders. CONCLUSION: Our findings indicate that tumor antigen-specific T cells are present in the peripheral blood of patients with HPV-positive HNSCC. Blockade of checkpoint pathways can enhance T-cell responses in certain patients, probably via activated T cells, Tregs, and/or exhausted CD4+ T cells.


Assuntos
Neoplasias de Cabeça e Pescoço , Inibidores de Checkpoint Imunológico , Infecções por Papillomavirus , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/virologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Antígenos de Neoplasias/imunologia , Proteínas Oncogênicas Virais/imunologia , Proteína Supressora de Tumor p53/imunologia , Adulto , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Papillomaviridae/imunologia , Linfócitos T/imunologia , Papillomavirus Humano
18.
Genes (Basel) ; 14(2)2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36833347

RESUMO

Natural antioxidants derived from plants exert various physiological effects, including antitumor effects. However, the molecular mechanisms of each natural antioxidant have not yet been fully elucidated. Identifying the targets of natural antioxidants with antitumor properties in vitro is costly and time-consuming, and the results thus obtained may not reliably reflect in vivo conditions. Therefore, to enhance understanding regarding the antitumor effects of natural antioxidants, we focused on DNA, one of the targets of anticancer drugs, and evaluated whether antioxidants, e.g., sulforaphane, resveratrol, quercetin, kaempferol, and genistein, which exert antitumor effects, induce DNA damage using gene-knockout cell lines derived from human Nalm-6 and HeLa cells pretreated with the DNA-dependent protein kinase inhibitor NU7026. Our results suggested that sulforaphane induces single-strand breaks or DNA strand crosslinks and that quercetin induces double-strand breaks. In contrast, resveratrol showed the ability to exert cytotoxic effects other than DNA damage. Our results also suggested that kaempferol and genistein induce DNA damage via unknown mechanisms. Taken together, the use of this evaluation system facilitates the analysis of the cytotoxic mechanisms of natural antioxidants.


Assuntos
Antioxidantes , Quebras de DNA de Cadeia Dupla , Humanos , Antioxidantes/farmacologia , Quempferóis , Resveratrol , Quercetina , Células HeLa , Genisteína , DNA
19.
Sci Rep ; 13(1): 3233, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829054

RESUMO

Frequency-modulated continuous wave radar techniques typically have inadequate angular resolutions due to the limited aperture sizes of antenna arrays in spite of employing multiple-input multiple-output (MIMO) techniques. Therefore, despite the existence of multiple objects, angularly close objects with similar distances and relative velocities are recognized as one single object. Autonomous driving requires the accurate recognition of road conditions. This requirement is one of the critical issues to be solved to distinguish significantly close objects. This paper proposes a technique referred to as an antenna element space pseudo-peak suppressing (APPS) method to resolve angularly close targets. The proposed APPS method aims to identify closely spaced objects on roads. These angularly close targets cause a single peak in a spatial spectrum obtained by a beamformer-based angle estimation. The APPS considers this single peak as pseudo. The APPS radar cancels this pseudo peak from the spatial spectrum. Then, the obtained residual received signal is analyzed. With these procedures, the APPS identifies the number of targets. The APPS also estimates the target angles. The proposed APPS is experimentally validated using a typical single-chip MIMO-based radar evaluation board with three transmit (TX) and four receive (RX) antennas. The experimental results confirm that the proposed APPS successfully resolves angularly close pseudo targets with an angle difference of approximately [Formula: see text].

20.
Oral Oncol ; 136: 106270, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36462328

RESUMO

OBJECTIVES: Exosome-mediated reciprocal crosstalk between tumor and stromal cells plays a crucial role in tumor development and progression. This study investigated whether exosomes released from head and neck squamous cell carcinoma (HNSCC) tumor cells can convert normal fibroblasts into cancer-associated fibroblasts (CAF)-like cells and further analyzed the functional characterization of fibroblasts educated by tumor-derived exosomes. MATERIALS AND METHODS: Exosomes secreted from HNSCC cell lines were isolated and normal fibroblasts were established from normal oropharyngeal mucosa. The effects of the exosomes on fibroblasts were examined by proliferation and migration assays, and exosome-educated fibroblasts were analyzed for the expression of eight genes (IL1B, IL6, CXCL8, TGFB1, ACTA2, FAP, CD274, and PDCD1LG2) by RT-qPCR. Moreover, T cells or CD14-positive cells were co-cultured with culture supernatants from exosome-educated fibroblasts. T-cell proliferation and macrophage polarization were examined using flow cytometry. Then, RNA sequencing (RNA-seq) of exosome-educated fibroblasts and the corresponding control fibroblasts was performed. RESULTS: Tumor-derived exosomes enhanced fibroblast proliferation and migration. Moreover, gene expression analysis revealed upregulation of the gene expression of proinflammatory cytokines and immunoregulatory genes, and activated fibroblast marker genes. The culture supernatants of tumor-derived exosome-educated fibroblasts suppressed T cell proliferation and the induction of protumoral macrophages compared with those of control fibroblasts. Next, comprehensive RNA-seq analysis data revealed the activation of 11 signaling pathways, including IL-6- and IL-17-related signaling. CONCLUSION: These results indicate that HNSCC tumor cells induce and/or differentiate into CAFs through exosome-based cell-to-cell communication to create an inflammatory tumor microenvironment.


Assuntos
Fibroblastos Associados a Câncer , Exossomos , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fibroblastos Associados a Câncer/metabolismo , Exossomos/metabolismo , Microambiente Tumoral , Fibroblastos/metabolismo , Proliferação de Células , Neoplasias de Cabeça e Pescoço/patologia , Linhagem Celular Tumoral
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