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1.
Ann Med ; 54(1): 3189-3200, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36369824

RESUMO

INTRODUCTION: In order to identify therapeutic targets in Coronavirus disease 2019 (COVID-19), it is important to identify molecules involved in the biological responses that are modulated in COVID-19. Lysophosphatidic acids (LPAs) are involved in the pulmonary inflammation and fibrosis are one of the candidate molecules. The aim of this study was to evaluate the association between the serum levels of autotaxin (ATX), which are enzymes involved in the synthesis of lysophosphatidic acids. MATERIAL AND METHODS: We enrolled 134 subjects with COVID-19 and 58 normal healthy subjects for the study. We measured serum ATX levels longitudinally in COVID-19 patients and investigated the time course and the association with severity and clinical parameters. RESULTS: The serum ATX levels were reduced in all patients with COVID-19, irrespective of the disease severity, and were negatively associated with the serum CRP, D-dimer, and anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody levels. DISCUSSION: Considering the biological properties of LPAs in the pulmonary inflammation and fibrosis, modulation of ATX might be compensatory biological responses to suppress immunological overreaction especially in the lung, which is an important underlying mechanism for the mortality of the disease. CONCLUSIONS: COVID-19 patients showed a decrease in the serum levels of ATX, irrespective of the disease severity. Key MessagesAutotaxin (ATX) is an enzyme involved in the synthesis of lysophosphatidic acid (LPA), which has been reported to be involved in pulmonary inflammation and fibrosis. Patients with COVID-19 show decrease in the serum levels of ATX. Modulation of ATX might be compensatory biological responses to suppress immunological overreaction.


Assuntos
COVID-19 , Diester Fosfórico Hidrolases , Humanos , COVID-19/sangue , Fibrose , Pulmão , Lisofosfolipídeos , Diester Fosfórico Hidrolases/sangue , SARS-CoV-2
2.
Front Mol Biosci ; 9: 1040237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419930

RESUMO

The type 2 Ca2+-dependent activator protein for secretion (CAPS2/CADPS2) regulates dense-core vesicle trafficking and exocytosis and is involved in the regulated release of catecholamines, peptidergic hormones, and neuromodulators. CAPS2 is expressed in the pancreatic exocrine acinar cells that produce and secrete digestive enzymes. However, the functional role of CAPS2 in vesicular trafficking and/or exocytosis of non-regulatory proteins in the exocrine pancreas remains to be determined. Here, we analyzed the morpho-pathological indicators of the pancreatic exocrine pathway in Cadps2-deficient mouse models using histochemistry, biochemistry, and electron microscopy. We used whole exosome sequencing to identify CADPS2 variants in patients with chronic pancreatitis (CP). Caps2/Cadps2-knockout (KO) mice exhibited morphophysiological abnormalities in the exocrine pancreas, including excessive accumulation of secretory granules (zymogen granules) and their amylase content in the cytoplasm, deterioration of the fine intracellular membrane structures (disorganized rough endoplasmic reticulum, dilated Golgi cisternae, and the appearance of empty vesicles and autophagic-like vacuoles), as well as exocrine pancreatic cell injury, including acinar cell atrophy, increased fibrosis, and inflammatory cell infiltration. Pancreas-specific Cadps2 conditional KO mice exhibited pathological abnormalities in the exocrine pancreas similar to the global Cadps2 KO mice, indicating that these phenotypes were caused either directly or indirectly by CAPS2 deficiency in the pancreas. Furthermore, we identified a rare variant in the exon3 coding region of CADPS2 in a non-alcoholic patient with CP and showed that Cadps2-dex3 mice lacking CAPS2 exon3 exhibited symptoms similar to those exhibited by the Cadps2 KO and cKO mice. These results suggest that CAPS2 is critical for the proper functioning of the pancreatic exocrine pathway, and its deficiency is associated with a risk of pancreatic acinar cell pathology.

3.
Biochim Biophys Acta Mol Basis Dis ; 1868(4): 166339, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35017029

RESUMO

The pancreatic islet vasculature is of fundamental importance to the ß-cell response to obesity-associated insulin resistance. To explore islet vascular alterations in the pathogenesis of type 2 diabetes, we evaluated two insulin resistance models: ob/ob mice, which sustain large ß-cell mass and hyperinsulinemia, and db/db mice, which progress to diabetes due to secondary ß-cell compensation failure for insulin secretion. Time-dependent changes in islet vasculature and blood flow were investigated using tomato lectin staining and in vivo live imaging. Marked islet capillary dilation was observed in ob/ob mice, but this adaptive change was blunted in db/db mice. Islet blood flow volume was augmented in ob/ob mice, whereas it was reduced in db/db mice. The protein concentrations of total and phosphorylated endothelial nitric oxide synthase (eNOS) at Ser1177 were increased in ob/ob islets, while they were diminished in db/db mice, indicating decreased eNOS activity. This was accompanied by an increased retention of advanced glycation end-products in db/db blood vessels. Amelioration of diabetes by Elovl6 deficiency involved a restoration of capillary dilation, blood flow, and eNOS phosphorylation in db/db islets. Our findings suggest that the disability of islet capillary dilation due to endothelial dysfunction impairs local islet blood flow, which may play a role in the loss of ß-cell function and further exacerbate type 2 diabetes.


Assuntos
Vasos Sanguíneos/metabolismo , Ilhotas Pancreáticas/fisiologia , Animais , Velocidade do Fluxo Sanguíneo , Diabetes Mellitus Tipo 2/patologia , Modelos Animais de Doenças , Elongases de Ácidos Graxos/deficiência , Elongases de Ácidos Graxos/genética , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Insulina/metabolismo , Resistência à Insulina , Ilhotas Pancreáticas/anatomia & histologia , Ilhotas Pancreáticas/irrigação sanguínea , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação
4.
Int Immunopharmacol ; 103: 108491, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34954559

RESUMO

To better understand the immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in individuals with COVID-19, it is important to investigate the kinetics of the antibody responses and their associations with the clinical course in different populations, since there seem to be considerable differences between Western and Asian populations in the clinical features and spread of COVID-19. In this study, we serially measured the serum titers of IgM, IgG and IgA antibodies generated against the nucleocapsid protein (NCP), S1 subunit of the spike protein (S1), and receptor-binding domain in the S1 subunit (RBD) of SARS-CoV-2 in Japanese individuals with COVID-19. Among the IgM, IgG, and IgA antibodies, IgA antibodies against all of the aforementioned viral proteins were the first to appear after the infection, and IgG and/or IgA seroconversion often preceded IgM seroconversion. In regard to the timeline of the antibody responses to the different viral proteins (NCP, S1 and RBD), IgA against NCP appeared than IgA against S1 or RBD, while IgM and IgG against S1 appeared earlier than IgM/IgG against NCP or RBD. The IgG responses to all three viral proteins and responses of all three antibody classes to S1 and RBD were sustained for longer durations than the IgA/IgM responses to all three viral proteins and responses of all three antibody classes to NCP, respectively. The seroconversion of IgA against NCP occurred later and less frequently in patients with mild COVID-19. These results suggest possible differences in the antibody responses to SARS-CoV-2 antigens between the Japanese and Western populations.


Assuntos
COVID-19/epidemiologia , COVID-19/imunologia , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , SARS-CoV-2 , Formação de Anticorpos , Povo Asiático , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Japão/epidemiologia , Japão/etnologia , Soroconversão , Proteínas Virais/imunologia
6.
Langmuir ; 37(31): 9451-9456, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34325512

RESUMO

Multipoint lock-and-key particle assembly, consisting of lock particles with multiple anisotropic dents and rod-shaped particles as key particles, is developed for colloidal modeling application. The lock particles were connected with each other at a key particle as their joint in the presence of depletants, forming rigid colloidal molecules imitating rigid polymers (e.g., polymers containing aromatic rings and intramolecular hydrogen bonds). A single-particle level observation was conducted to visualize the colloidal polymerization of the particle assembly. Motion trajectories of the lock particles observed by optical microscopy indicated that the particle diffusivity was dramatically lowered when the lock particle connected with another one, suggesting that particle diffusion was suppressed by particle assembly formation. Because the kinetic and regioselectivity of colloidal polymerization are assumed to be analogous to those at the atomic scale, the proposed lock-and-key assembly can be a promising colloidal model for atomic-scale polymers associated with their micro-Brownian motion.

7.
J Infect Chemother ; 27(9): 1342-1349, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34158239

RESUMO

INTRODUCTION: The worldwide pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to date. Given that some of the patients with coronavirus disease 2019 (COVID-19) are asymptomatic, antibody tests are useful to determine whether there is a previous infection with SARS-CoV-2. In this study, we measured IgM and IgG antibody titers against SARS-CoV-2 in the serum of asymptomatic healthy subjects in The University of Tokyo, Japan. METHODS: From June 2020, we recruited participants, who were students, staff, and faculty members of The University of Tokyo in the project named The University of Tokyo COVID-19 Antibody Titer Survey (UT-CATS). Following blood sample collection, participants were required to answer an online questionnaire about their social and health information. We measured IgG and IgM titers against SARS-CoV-2 using iFlash-SARS-CoV-2 IgM and IgG detection kit which applies a chemiluminescent immunoassay (CLIA) for the qualitative detection. RESULTS: There were 6609 volunteers in this study. After setting the cutoff value at 10 AU/mL, 32 (0.48%) were positive for IgG and 16 (0.24%) for IgM. Of six participants with a history of COVID-19, five were positive for IgG, whereas all were negative for IgM. The median titer of IgG was 0.40 AU/mL and 0.39 AU/mL for IgM. Both IgG and IgM titers were affected by gender, age, smoking status, and comorbidities. CONCLUSIONS: Positive rates of IgG and IgM titers were relatively low in our university. Serum levels of these antibodies were affected by several factors, which might affect the clinical course of COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Estudos Epidemiológicos , Humanos , Imunoglobulina G , Imunoglobulina M , Japão/epidemiologia
8.
Sci Rep ; 11(1): 5190, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664450

RESUMO

In Coronavirus disease 2019 (COVID-19) subjects, recent evidence suggests the presence of unique coagulation abnormalities. In this study, we performed clot waveform analyses to investigate whether specific modulations are observed in COVID-19 subjects. We analyzed the second derivative of the absorbance in routine APTT tests performed using an ACL-TOP system. We observed high frequencies of abnormal patterns in APTT second-derivative curves that could be classified into an early shoulder type, a late shoulder type, or a biphasic type, high maximum first-derivative and second-derivative peak levels, and a low minimum second-derivative peak level in COVID-19 subjects. These modulations were not observed in subjects with disseminated intravascular coagulation. These abnormal patterns are also observed in patients with lupus anticoagulant, hemophilia, or factor IX deficiency. The plasma fibrinogen levels might also be involved in the abnormal APTT waveforms, especially the high maximum first-derivative and second-derivative peak levels. The abnormal patterns in the APTT second-derivative curves appear with highest frequency at around 2 weeks after the onset of COVID-19 and were not associated with the severity of COVID-19. These results suggest the possible presence of a specific abnormal coagulopathy in COVID-19.


Assuntos
Coagulação Sanguínea , COVID-19/sangue , Idoso , Testes de Coagulação Sanguínea , Feminino , Fibrinogênio/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos , Triazóis
9.
PLoS One ; 16(3): e0247711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661990

RESUMO

PCR methods are presently the standard for the diagnosis of Coronavirus disease 2019 (COVID-19), but additional methodologies are needed to complement PCR methods, which have some limitations. Here, we validated and investigated the usefulness of measuring serum antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using the iFlash3000 CLIA analyzer. We measured IgM and IgG titers against SARS-CoV-2 in sera collected from 26 PCR-positive COVID-19 patients, 53 COVID-19-suspected but PCR-negative patients, and 20 and 100 randomly selected non-COVID-19 patients who visited our hospital in 2020 and 2017, respectively. The repeatability and within-laboratory precision were obviously good in validations, following to the CLSI document EP15-A3. Linearity was also considered good between 0.6 AU/mL and 112.7 AU/mL for SARS-CoV-2 IgM and between 3.2 AU/mL and 55.3 AU/mL for SARS-CoV-2 IgG, while the linearity curves plateaued above the upper measurement range. We also confirmed that the seroconversion and no-antibody titers were over the cutoff values in all 100 serum samples collected in 2017. These results indicate that this measurement system successfully detects SARS-CoV-2 IgM/IgG. We observed four false-positive cases in the IgM assay and no false-positive cases in the IgG assay when 111 serum samples known to contain autoantibodies were evaluated. The concordance rates of the antibody test with the PCR test were 98.1% for SARS-CoV-2 IgM and 100% for IgG among PCR-negative cases and 30.8% for SARS-CoV-2 IgM and 73.1% for SARS-CoV-2 IgG among PCR-positive cases. In conclusion, the performance of this new automated method for detecting antibody against both N and S proteins of SARS-CoV-2 is sufficient for use in laboratory testing.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Imunoglobulina G/sangue , Imunoglobulina M/sangue , SARS-CoV-2/isolamento & purificação , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/epidemiologia , COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/isolamento & purificação , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Japão/epidemiologia , Medições Luminescentes/métodos , Fosfoproteínas/imunologia , Fosfoproteínas/isolamento & purificação , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/isolamento & purificação
10.
Sci Rep ; 11(1): 2776, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531605

RESUMO

The accurate and prompt diagnosis of SARS-CoV-2 infection is required for the control and treatment of the coronavirus infection disease 2019 (COVID-19). In this study, we aimed to investigate the time courses of the anti-severe acute corona respiratory syndrome coronavirus 2 (SARS-CoV-2) IgM and IgG titers and to evaluate the sensitivity and specificity of such tests according to the specific day after the onset of COVID-19 among a patient population in Japan. We measured the titers of SARS-CoV-2 IgM and IgG in sera from 105 subjects, including 26 symptomatic COVID-19 patients, using chemiluminescent immunoassay (CLIA) methods utilizing magnetic beads coated with SARS-CoV-2 nucleocapsid protein and spike protein. The results of a ROC analysis suggested the possibility that the cutoff values in Japan might be lower than the manufacturer's reported cutoff (10 AU/mL): 1  AU/mL for IgM and 5  AU/mL for IgG. The sensitivity of the test before Day 8 after symptom onset was less than 50%; at Days 9-10, however, we obtained a much higher sensitivity of 81.8% for both IgM and IgG. At 15 days or later after symptom onset, the SARS-CoV-2 IgG test had a sensitivity of 100%. These results suggest that if the number of days since disease onset is taken into consideration, these antibody tests could be very useful for the diagnosis of COVID-19 and similar diseases.


Assuntos
Especificidade de Anticorpos , COVID-19/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , SARS-CoV-2/imunologia , COVID-19/virologia , Teste para COVID-19 , Ensaio de Imunoadsorção Enzimática , Humanos , Japão
11.
Virology ; 542: 28-33, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31957663

RESUMO

Horizontal pollen transmission by the raspberry bushy dwarf virus 1b deletion mutant (RBΔ1bstop), which is defective in virus virulence, was significantly decreased compared to wild-type raspberry bushy dwarf virus (wtRBDV). We assessed accumulation of viral genomic (g) RNAs in pollen grains from RBΔ1bstop-infected plants and found that the pollen grains had less viral gRNA than those from wtRBDV-infected plants. In addition, pollen grains from 1b-expressing transgenic plants (1b-plants) infected with RBΔ1bstop were more efficient in horizontal virus transmission to healthy plants after pollination than pollen from RBΔ1bstop-infected wild type plants. Moreover, viral gRNA accumulation in pollen grains from RBΔ1bstop-infected 1b-plants was higher than in pollen from RBΔ1bstop-infected wild type plants. We suggest that 1b increases the amount of viral gRNAs released from elongating pollen grains.


Assuntos
Genes Virais , Doenças das Plantas/virologia , Vírus de Plantas/genética , Pólen/virologia , Rubus/virologia , Transmissão de Doença Infecciosa , Hibridização In Situ , Mutação , Vírus de Plantas/patogenicidade , Plantas Geneticamente Modificadas , Polinização , Vírus de RNA/genética , Vírus de RNA/patogenicidade , RNA Viral/genética , RNA Viral/metabolismo , Rubus/fisiologia , Nicotiana/genética , Nicotiana/fisiologia , Nicotiana/virologia
12.
Hepatology ; 71(5): 1609-1625, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31529722

RESUMO

BACKGROUND AND AIMS: Dysfunctional hepatic lipid metabolism is a cause of nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disorder worldwide, and is closely associated with insulin resistance and type 2 diabetes. ELOVL fatty acid elongase 6 (Elovl6) is responsible for converting C16 saturated and monounsaturated fatty acids (FAs) into C18 species. We have previously shown that Elovl6 contributes to obesity-induced insulin resistance by modifying hepatic C16/C18-related FA composition. APPROACH AND RESULTS: To define the precise molecular mechanism by which hepatic Elovl6 affects energy homeostasis and metabolic disease, we generated liver-specific Elovl6 knockout (LKO) mice. Unexpectedly, LKO mice were not protected from high-fat diet-induced insulin resistance. Instead, LKO mice exhibited higher insulin sensitivity than controls when consuming a high-sucrose diet (HSD), which induces lipogenesis. Hepatic patatin-like phospholipase domain-containing protein 3 (Pnpla3) expression was down-regulated in LKO mice, and adenoviral Pnpla3 restoration reversed the enhancement in insulin sensitivity in HSD-fed LKO mice. Lipidomic analyses showed that the hepatic ceramide(d18:1/18:0) content was lower in LKO mice, which may explain the effect on insulin sensitivity. Ceramide(d18:1/18:0) enhances protein phosphatase 2A (PP2A) activity by interfering with the binding of PP2A to inhibitor 2 of PP2A, leading to Akt dephosphorylation. Its production involves the formation of an Elovl6-ceramide synthase 4 (CerS4) complex in the endoplasmic reticulum and a Pnpla3-CerS4 complex on lipid droplets. Consistent with this, liver-specific Elovl6 deletion in ob/ob mice reduced both hepatic ceramide(d18:1/18:0) and PP2A activity and ameliorated insulin resistance. CONCLUSIONS: Our study demonstrates the key role of hepatic Elovl6 in the regulation of the acyl-chain composition of ceramide and that C18:0-ceramide is a potent regulator of hepatic insulin signaling linked to Pnpla3-mediated NAFLD.


Assuntos
Ceramidas/metabolismo , Elongases de Ácidos Graxos/fisiologia , Resistência à Insulina/genética , Fígado/enzimologia , Animais , Ceramidas/química , Sacarose Alimentar/administração & dosagem , Regulação para Baixo , Elongases de Ácidos Graxos/genética , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fosfolipases A2 Independentes de Cálcio/metabolismo , Proteína Fosfatase 2/metabolismo , Esfingosina N-Aciltransferase/metabolismo
13.
Sci Rep ; 9(1): 5169, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30914769

RESUMO

Brown adipose tissue (BAT) is an attractive therapeutic target for treating obesity and metabolic diseases. Octacosanol is the main component of policosanol, a mixture of very long chain aliphatic alcohols obtained from plants. The current study aimed to investigate the effect of octacosanol and policosanol on high-fat diet (HFD)-induced obesity. Mice were fed on chow, or HFD, with or without octacosanol or policosanol treatment for four weeks. HFD-fed mice showed significantly higher body weight and body fat compared with chow-fed mice. However, mice fed on HFD treated with octacosanol or policosanol (HFDo/p) showed lower body weight gain, body fat gain, insulin resistance and hepatic lipid content. Lower body fat gain after octacosanol or policosanol was associated with increased BAT activity, reduced expression of genes involved in lipogenesis and cholesterol uptake in the liver, and amelioration of white adipose tissue (WAT) inflammation. Moreover, octacosanol and policosanol significantly increased the expression of Ffar4, a gene encoding polyunsaturated fatty acid receptor, which activates BAT thermogenesis. Together, these results suggest that octacosanol and policosanol ameliorate diet-induced obesity and metabolic disorders by increasing BAT activity and improving hepatic lipid metabolism. Thus, these lipids represent promising therapeutic targets for the prevention and treatment of obesity and obesity-related metabolic disorders.


Assuntos
Tecido Adiposo Marrom/metabolismo , Dieta Hiperlipídica , Álcoois Graxos/uso terapêutico , Fígado/metabolismo , Doenças Metabólicas/tratamento farmacológico , Obesidade/tratamento farmacológico , Obesidade/prevenção & controle , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Álcoois Graxos/farmacologia , Fígado Gorduroso/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/patologia , Insulina/sangue , Fígado/efeitos dos fármacos , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/genética , Camundongos Endogâmicos C57BL , Obesidade/sangue , Obesidade/genética , Regulação para Cima/efeitos dos fármacos
14.
J Colloid Interface Sci ; 534: 81-87, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30216835

RESUMO

Colloidal molecules created by clustering monodisperse particles are a significant model system of atoms and molecules in colloidal scale. To attain modelling of complex or high-molecular-weight molecules such as hyper-branched polymers and proteins, it is required to develop a new assembling system which can prepare three-dimensionally designed colloidal molecules. In this study, we proposed an approach for complex colloidal molecules created by association between golf ball-like particles and spherical particles via depletion interaction. Several golf ball-like particles joined together, which formed joined particle assemblies at the spherical particles acting as their joints in a depletant solution. The number of golf ball-like particles in a particle assembly was increased by increasing the concentration of the depletant, leading to the formation of branched colloidal chains of the golf ball-like particles. Because the golf ball-like particles in the colloidal chain flexibly rotated at their joints, the conformation of the chains varied in the depletant solution. The present results demonstrated that the golf-ball like particle that can be joined to form colloidal macromolecules with high association number and high flexibility will be a promising building block for complex colloidal model systems.

15.
Ann Clin Biochem ; 56(2): 240-246, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30514094

RESUMO

BACKGROUND: Invasion of the central nervous system by haematological malignancies is diagnosed by cytological analyses of cerebrospinal fluid or diagnostic imaging, while quantitative biomarkers for central nervous system invasion are not available and needed to be developed. METHODS: In this study, we measured the concentrations of autotaxin and soluble IL-2 receptor in cerebrospinal fluid and evaluated their usefulness as biomarkers for central nervous system invasion. RESULTS: We observed that both the autotaxin and soluble IL-2 receptor concentrations in cerebrospinal fluid were higher in subjects with central nervous system invasion than in those without, and the cerebrospinal fluid concentrations were independent from the serum concentrations of these biomarkers. ROC analyses revealed that the soluble IL-2 receptor concentration in cerebrospinal fluid was a strong discriminator of central nervous system invasion in subjects with haematological malignancies, while the autotaxin concentration in cerebrospinal fluid also had a strong ability to discriminate central nervous system invasion when the subjects were limited to those with lymphoma. The combined measurement of autotaxin and soluble IL-2 receptor in cerebrospinal fluid improved the sensitivity without notably reducing the specificity for central nervous system invasion in subjects with lymphoma when central nervous system invasion was diagnosed in cases where either value was beyond the respective cut-off value. CONCLUSION: These results suggest the possible usefulness of soluble IL-2 receptor and autotaxin concentrations in cerebrospinal fluid for the diagnosis of central nervous system invasion.


Assuntos
Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias Hematológicas/líquido cefalorraquidiano , Neoplasias Hematológicas/patologia , Diester Fosfórico Hidrolases/líquido cefalorraquidiano , Receptores de Interleucina-2/química , Receptores de Interleucina-2/metabolismo , Neoplasias do Sistema Nervoso Central/secundário , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Curva ROC , Solubilidade
16.
Endocrinology ; 159(6): 2308-2323, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29668871

RESUMO

Sterol regulatory element-binding protein (SREBP)-1a is a key transcription factor that activates the expression of genes involved in the synthesis of fatty acids, triglycerides (TGs), and cholesterol. Transgenic mice that overexpress the nuclear form of SREBP-1a under the control of the phosphoenolpyruvate carboxykinase promoter (Tg-1a) were previously shown to display a lipodystrophic phenotype characterized by enlarged and fatty livers, diminished peripheral white adipose tissue (WAT), and insulin resistance. In the current study, we crossed these Tg-1a mice with genetically obese (ob/ob) mice (Tg-1a;ob/ob) and examined change in fat distribution between liver and adipose tissues in severe obesity and mechanism underlying the lipodystrophic phenotype in mice with Tg-1a. Tg-1a;ob/ob mice developed more severe steatohepatitis but had reduced WAT mass and body weight compared with ob/ob mice. The reduction of WAT mass in Tg-1a and Tg-1a;ob/ob mice was accompanied by enhanced lipogenesis and lipid uptake in the liver, reduced plasma lipid levels, impaired adipocyte differentiation, reduced food intake, enhanced energy expenditure, and extended macrophage infiltration and fibrosis in WAT. Despite the improved glucose tolerance, Tg-1a;ob/ob mice showed severe peripheral insulin resistance. Adenoviral hepatic expression of SREBP-1a mimicked these phenotypes. The "fat steal"-like lipodystrophy phenotype of the Tg-1a;ob/ob model demonstrates that hepatic SREBP-1a activation has a strong impact on the partition of TG accumulation, resulting in adipose-tissue remodeling by inflammation and fibrosis and insulin resistance.


Assuntos
Resistência à Insulina/genética , Lipodistrofia/genética , Obesidade/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Animais , Células Cultivadas , Progressão da Doença , Feminino , Lipodistrofia/complicações , Lipodistrofia/patologia , Masculino , Síndrome Metabólica/genética , Síndrome Metabólica/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Camundongos Transgênicos , Obesidade/complicações , Obesidade/patologia
17.
Virology ; 484: 341-345, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26176979

RESUMO

We developed a fertilization method in which pollen tubes entered into embryo sacs without any need to contact surrounding female sporophytic cells by using Torenia fournieri (Torenia) plants under the condition of hindering movement of the virus from a stigma, which is the first infection site leading to systemic infection. When RBDV-infected Torenia pollen grains were used for the developed fertilization method, the virus was transmitted to the seeds by pollen tubes germinating from them. On the other hand, no seeds were infected with the virus when Torenia plants were pollinated with healthy Torenia pollen grains in combination with RBDV-infected raspberry pollen grains, which caused the virus infection in the stigma by penetration of their pollen tubes arrested in its style. Our results indicate that vertical transmission of RBDV by pollen occurs in the transport of the virus into embryo sacs by pollen tubes reaching the embryo sacs.


Assuntos
Fertilização , Magnoliopsida/fisiologia , Magnoliopsida/virologia , Doenças das Plantas/virologia , Tubo Polínico/virologia , Vírus de RNA/fisiologia , Sementes/virologia , Vírus de RNA/isolamento & purificação
18.
J Acoust Soc Am ; 133(1): EL61-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23298019

RESUMO

Very long-range underwater acoustic communication (UAC) is crucial for long cruising (>1000 km) autonomous underwater vehicles (AUVs). Very long-range UAC source for AUV must exhibit high electro-acoustic efficiency (>60%) and compactness. This paper describes the Janus-Hammer Bell (JHB) transducer that has been designed for this purpose and meets those requirements. The transducer works on the 450-550 Hz bandwidth and reaches source level above 200 dB (ref. 1 µPa at 1 m) with 1 kW excitation and full immersion capability. JHB source has been used for communication experiments by the Japanese institute for marine technology (Japan Agency for Marine-Earth Science and Technology) achieving a baud rate of 100 bits/s at 1000 km.


Assuntos
Acústica/instrumentação , Som , Telecomunicações/instrumentação , Transdutores , Água , Desenho de Equipamento , Análise de Elementos Finitos , Modelos Teóricos , Movimento (Física) , Processamento de Sinais Assistido por Computador , Espectrografia do Som , Fatores de Tempo
19.
Proc Natl Acad Sci U S A ; 109(7): 2382-7, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22308378

RESUMO

Nitric oxide (NO) is implicated in neuronal cell survival. However, excessive NO production mediates neuronal cell death, in part via mitochondrial dysfunction. Here, we report that the mitochondrial ubiquitin ligase, MITOL, protects neuronal cells from mitochondrial damage caused by accumulation of S-nitrosylated microtubule-associated protein 1B-light chain 1 (LC1). S-nitrosylation of LC1 induces a conformational change that serves both to activate LC1 and to promote its ubiquination by MITOL, indicating that microtubule stabilization by LC1 is regulated through its interaction with MITOL. Excessive NO production can inhibit MITOL, and MITOL inhibition resulted in accumulation of S-nitrosylated LC1 following stimulation of NO production by calcimycin and N-methyl-D-aspartate. LC1 accumulation under these conditions resulted in mitochondrial dysfunction and neuronal cell death. Thus, the balance between LC1 activation by S-nitrosylation and down-regulation by MITOL is critical for neuronal cell survival. Our findings may contribute significantly to an understanding of the mechanisms of neurological diseases caused by nitrosative stress-mediated mitochondrial dysfunction.


Assuntos
Morte Celular , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Neurônios/citologia , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Proteínas de Membrana , Mitocôndrias/fisiologia , Compostos Nitrosos/metabolismo , Proteólise , Ubiquitinação
20.
Chem Commun (Camb) ; (42): 6403-5, 2009 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-19841790

RESUMO

Aromatic polymers containing perfluorosulfonic acid groups show well-developed and interconnected ionic clusters, and thus high proton conductivity at wide humidity range.

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