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1.
Qual Manag Health Care ; 33(1): 12-17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37651580

RESUMO

BACKGROUND AND OBJECTIVES: Patient-safety climate is one of the most important organizational factors contributing to health care quality. We hypothesized that a patient safety climate is fostered by the willingness to collaborate and trust among members as well as by daily collaborative practices. This study aimed to clarify the effect of workplace social capital on patient safety climate. We also sought to investigate the mediating effect of interprofessional team collaboration on the relationship between workplace social capital and patient safety climate. METHODS: This cross-sectional survey was conducted from November 2021 to January 2022 using anonymous web-based questionnaires. The survey was distributed to 1495 employees working in a hospital in Tokyo, Japan. The questionnaire included the patient safety climate scale, workplace social capital scale, Japanese version of the Assessment of Interprofessional Team Collaboration Scale-II (AITCS-II-J), and demographic items. Structural equation modeling was performed to verify the associations among the 3 variables. In addition, a significance test for indirect effects was conducted using the bootstrap method to confirm the mediating effect of AITCS-II-J. RESULTS: A total of 725 employees participated in this survey, and 632 data items were analyzed. Nurses were the highest number of respondents (68.2%), followed by physicians (13.3%). Workplace social capital and patient safety were directly and significantly associated (ß = .309, P < .01). Furthermore, the partially indirect effect of the AITCS-II-J on the association between workplace social capital and patient safety climate was also significant (ß = .430, P < .01). CONCLUSIONS: Workplace social capital was significantly and directly related to patient safety climate and was also significantly related to patient safety climate partially mediated by interprofessional team collaboration. Our findings suggest the importance of workplace social capital and routine multidisciplinary collaboration for a patient safety climate to manage health care quality.


Assuntos
Capital Social , Humanos , Estudos Transversais , Segurança do Paciente , Local de Trabalho , Japão , Inquéritos e Questionários
2.
Plant Cell Physiol ; 65(2): 259-268, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37971366

RESUMO

Plants adopt optimal tolerance strategies depending on the intensity and duration of stress. Retaining water is a priority under short-term drought conditions, whereas maintaining growth and reproduction processes takes precedence over survival under conditions of prolonged drought. However, the mechanism underlying changes in the stress response depending on the degree of drought is unclear. Here, we report that SNF1-related protein kinase 2 (SnRK2) substrate 1 (SNS1) is involved in this growth regulation under conditions of drought stress. SNS1 is phosphorylated and stabilized by SnRK2 protein kinases reflecting drought conditions. It contributes to the maintenance of growth and promotion of flowering as drought escape by repressing stress-responsive genes and inducing FLOWERING LOCUS T (FT) expression, respectively. SNS1 interacts with the histone methylation reader proteins MORF-related gene 1 (MRG1) and MRG2, and the SNS1-MRG1/2 module cooperatively regulates abscisic acid response. Taken together, these observations suggest that the phosphorylation and accumulation of SNS1 in plants reflect the intensity and duration of stress and can serve as a molecular scale for maintaining growth and adopting optimal drought tolerance strategies under stress conditions.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Secas , Resistência à Seca , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Cromossômicas não Histona/metabolismo
3.
J Chromatogr A ; 1708: 464333, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37660558

RESUMO

We evaluated the suitability of supercritical fluid chromatography (SFC) for oligonucleotide analysis using 4-mer oligonucleotides with various phosphorothioate (PS) contents as model compounds. Column screening showed that the diol-modified column was able to separate sequences with different PS contents. Optimization of the column body and additives allowed us to analyze polar oligonucleotides using SFC. Various sequences were also analyzed using the optimized method. A good peak shape was obtained when the guanine plus cytosine content of the analyte was two or less in the 4-mer oligonucleotides. Furthermore, we found that the retention times of the selected sequences were positively correlated with polar surface areas, indicating that oligonucleotides interact with polar stationary phases. In contrast, more hydrophobic full PS sequences were retained more strongly in the diol column than the full phosphodiester (PO) sequences. This suggests that the diol column has unique selectivity for PO and PS linkages. These results indicate that SFC is potentially applicable to oligonucleotide analysis with a separation mechanism that is different from that of ion-pair reversed-phase liquid chromatography.


Assuntos
Cromatografia com Fluido Supercrítico , Estudo de Prova de Conceito , Cromatografia de Fase Reversa , Oligonucleotídeos
4.
Cell Rep ; 42(3): 112165, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36862552

RESUMO

Inflammatory stimuli cause a state of emergency myelopoiesis leading to neutrophil-like monocyte expansion. However, their function, the committed precursors, or growth factors remain elusive. In this study we find that Ym1+Ly6Chi monocytes, an immunoregulatory entity of neutrophil-like monocytes, arise from progenitors of neutrophil 1 (proNeu1). Granulocyte-colony stimulating factor (G-CSF) favors the production of neutrophil-like monocytes through previously unknown CD81+CX3CR1lo monocyte precursors. GFI1 promotes the differentiation of proNeu2 from proNeu1 at the cost of producing neutrophil-like monocytes. The human counterpart of neutrophil-like monocytes that also expands in response to G-CSF is found in CD14+CD16- monocyte fraction. The human neutrophil-like monocytes are discriminated from CD14+CD16- classical monocytes by CXCR1 expression and the capacity to suppress T cell proliferation. Collectively, our findings suggest that the aberrant expansion of neutrophil-like monocytes under inflammatory conditions is a process conserved between mouse and human, which may be beneficial for the resolution of inflammation.


Assuntos
Monócitos , Neutrófilos , Camundongos , Animais , Humanos , Monócitos/fisiologia , Mielopoese , Diferenciação Celular , Fator Estimulador de Colônias de Granulócitos
5.
J Reprod Dev ; 69(3): 147-153, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36935121

RESUMO

Progesterone (P) enhances spermatozoal hyperactivation, a capacitation event. Hyperactivation is associated with successful in vitro fertilization (IVF). In this study, we examined the effects of P on hyperactivation and IVF in mice. P enhanced spermatozoal hyperactivation and increased IVF success rate in a dose-dependent manner. Moreover, P affected spermatozoal hyperactivation and IVF through the membrane progesterone receptor of the spermatozoal head. These results show that P regulates spermatozoal capacitation and fertilization in mice. The concentration of P changes during the estrous cycle, indicating that spermatozoa are capacitated in response to the oviductal environment and subsequently fertilize the oocyte.


Assuntos
Progesterona , Capacitação Espermática , Masculino , Animais , Camundongos , Progesterona/farmacologia , Progesterona/fisiologia , Sêmen , Fertilização in vitro/métodos , Espermatozoides/fisiologia , Fertilização , Motilidade dos Espermatozoides
7.
J Atheroscler Thromb ; 30(1): 3-14, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35249932

RESUMO

AIMS: We established automated assay kits for quantifying small dense low-density lipoprotein (sdLDL)-cholesterol (C), LDL-triglyceride (TG), and high-density lipoprotein (HDL)3-C, and apolipoprotein (apo)E-rich HDL-C, and these have been recognized as sensitive biomarkers for predicting coronary artery disease. We investigated the circadian rhythms of these novel lipids to determine if fasting is required to determine basal levels. METHODS: Forty-eight inpatients with type 2 diabetes and 19 healthy volunteers were studied. Blood samples were collected at seven time points, which were obtained after an overnight fast, before and 2 h after each meal, and before the next breakfast. sdLDL-C, LDL-TG, remnant-like particle (RLP)-C, TG-rich lipoprotein (TRL-C), HDL3-C, and apoE-rich HDL-C were measured by the homogeneous methods. NonHDL-C, large buoyant (lb)LDL-C and HDL2-C were calculated by subtracting sdLDL-C from LDL-C or HDL3-C from HDL-C, respectively. RESULTS: Serum TG levels were significantly increased after meals in both healthy participants and patients with diabetes. RLP-C and TRL-C were also increased postprandially. LDL-TG, LDL-C, nonHDL-C, HDL2,3-C, and apoE-rich HDL-C did not exhibit significant fluctuation during the day in healthy participants and patients with diabetes. sdLDL-C was slightly increased postprandially in subjects with diabetes (1-2 mg/dl, 3%-9%), though its increase was not significant compared to the baseline (fasting) level. Significant postprandial reduction was observed with LDL-C and lbLDL-C. There was no influence of statin therapy or oral anti-diabetes drugs on the circadian rhythm of LDL-C subspecies. CONCLUSIONS: Subtle postprandial increase in sdLDL-C is considered a negligible level in general clinical practice. Fasting is not mandatory to measure basal concentrations of LDL and HDL subspecies.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , LDL-Colesterol , HDL-Colesterol , Voluntários Saudáveis , Triglicerídeos , Lipoproteínas HDL , Apolipoproteínas E , Ritmo Circadiano
8.
Genome Biol ; 23(1): 59, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35189950

RESUMO

BACKGROUND: Unraveling the relationship between genetic variation and phenotypic traits remains a fundamental challenge in biology. Mapping variants underlying complex traits while controlling for confounding environmental factors is often problematic. To address this, we establish a vertebrate genetic resource specifically to allow for robust genotype-to-phenotype investigations. The teleost medaka (Oryzias latipes) is an established genetic model system with a long history of genetic research and a high tolerance to inbreeding from the wild. RESULTS: Here we present the Medaka Inbred Kiyosu-Karlsruhe (MIKK) panel: the first near-isogenic panel of 80 inbred lines in a vertebrate model derived from a wild founder population. Inbred lines provide fixed genomes that are a prerequisite for the replication of studies, studies which vary both the genetics and environment in a controlled manner, and functional testing. The MIKK panel will therefore enable phenotype-to-genotype association studies of complex genetic traits while allowing for careful control of interacting factors, with numerous applications in genetic research, human health, drug development, and fundamental biology. CONCLUSIONS: Here we present a detailed characterization of the genetic variation across the MIKK panel, which provides a rich and unique genetic resource to the community by enabling large-scale experiments for mapping complex traits.


Assuntos
Oryzias , Animais , Genoma , Endogamia , Oryzias/genética , Fenótipo
9.
Genome Biol ; 23(1): 58, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35189951

RESUMO

BACKGROUND: The teleost medaka (Oryzias latipes) is a well-established vertebrate model system, with a long history of genetic research, and multiple high-quality reference genomes available for several inbred strains. Medaka has a high tolerance to inbreeding from the wild, thus allowing one to establish inbred lines from wild founder individuals. RESULTS: We exploit this feature to create an inbred panel resource: the Medaka Inbred Kiyosu-Karlsruhe (MIKK) panel. This panel of 80 near-isogenic inbred lines contains a large amount of genetic variation inherited from the original wild population. We use Oxford Nanopore Technologies (ONT) long read data to further investigate the genomic and epigenomic landscapes of a subset of the MIKK panel. Nanopore sequencing allows us to identify a large variety of high-quality structural variants, and we present results and methods using a pan-genome graph representation of 12 individual medaka lines. This graph-based reference MIKK panel genome reveals novel differences between the MIKK panel lines and standard linear reference genomes. We find additional MIKK panel-specific genomic content that would be missing from linear reference alignment approaches. We are also able to identify and quantify the presence of repeat elements in each of the lines. Finally, we investigate line-specific CpG methylation and performed differential DNA methylation analysis across these 12 lines. CONCLUSIONS: We present a detailed analysis of the MIKK panel genomes using long and short read sequence technologies, creating a MIKK panel-specific pan genome reference dataset allowing for investigation of novel variation types that would be elusive using standard approaches.


Assuntos
Oryzias , Animais , Epigenômica , Genoma , Genômica/métodos , Humanos , Oryzias/genética
10.
J Phys Ther Sci ; 34(1): 36-39, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35035077

RESUMO

[Purpose] Visual assessment of the quality of movement is a common and important component of physiotherapy. The purpose of this study is to quantify the level of proficiency of therapists and to obtain a new index of proficiency by measuring the coordinates of the gaze tracking trajectories of therapists with years of experience. [Participants and Methods] Eighteen voluntary physiotherapists (1st year (n=4), 7th year (n=1), 9th year (n=4), 10th year (n=3), 11th year (n=4), 13th year (n=1), and 21st year (n=1)) were recruited for this study. [Results] Discriminant analysis according to the size of the deviation between the X-axis and Y-axis of the range of gaze tracking during movement analysis measured from each therapist showed that the percentage of classification accuracy in the 10th year or less was 72.2%. Cluster analysis showed that two clusters were formed. Thirteen therapists in Cluster 2 were in their 9th year or more. Eye tracking trajectories can be classified by the 10th year of experience as a therapist. [Conclusion] It was shown that full-fledged therapists with 10 years of experience also expanded the range of eye tracking. The trajectory in the Y-axis direction tends to be extended with their 9th year or more of experience. In this point, quantitative judgments of eye-tracking results can serve as indicators of proficiency. The eye movements are important as a tool to objectively measure skills from experience.

11.
Intern Med ; 61(11): 1753-1755, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34803096

RESUMO

We herein report a 70-year-old man diagnosed with IgG4-related hypertrophic pachymeningitis with skull base involvement, who presented with isolated glossopharyngeal and vagus nerve palsy. Contrast-enhanced magnetic resonance imaging (MRI) showed enhanced dural thickening of the posterior clivus and skull base involvement. When a patient with hypertrophic pachymeningitis presents with isolated cranial neuropathy without systemic manifestations or definite MRI abnormalities, it is difficult to make a diagnosis, and the patient may be misdiagnosed. This case suggests that a detailed radiological evaluation including contrast enhancement of the skull base is very important in patients with isolated glossopharyngeal and vagus nerve palsy.


Assuntos
Imunoglobulina G , Meningite , Idoso , Humanos , Hipertrofia , Imageamento por Ressonância Magnética , Masculino , Meningite/diagnóstico , Meningite/diagnóstico por imagem , Paralisia , Base do Crânio/diagnóstico por imagem , Base do Crânio/patologia , Nervo Vago/patologia
12.
Geriatr Gerontol Int ; 22(1): 63-67, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34852400

RESUMO

AIM: Obesity is reported to be a risk factor for Clostridioides difficile infection. However, obesity rarely occurs in older Asian patients, and the effects of obesity on health and disease are different in Asian and Western countries. This study aimed to assess the association between body mass index and C. difficile infection risk among older patients with pneumonia in Japan. METHODS: This retrospective observational cohort study used data from the nationwide database of acute hospital inpatients' data in Japan between July 2014 and March 2016. All patients aged ≥65 years admitted with a primary diagnosis of pneumonia were enrolled. Risk factors for C. difficile infection were determined by logistic regression analysis, including known risks as covariates. RESULTS: Among 221 242 pneumonia patients, 611 developed C. difficile infection. Underweight patients (body mass index <18.5 kg/m2 ) showed higher odds for C. difficile infection (odds ratio 1.38, 95% confidence interval 1.17-1.62, P < 0.001) than normal weight patients (body mass index 18.5-24.9 kg/m2 ), whereas overweight patients (body mass index ≥25 kg/m2 ) showed lower odds (odds ratio 0.63, 95% confidence interval 0.45-0.89, P < 0.01). CONCLUSIONS: Body mass index was associated with C. difficile infection in older pneumonia patients in Japan. Underweight was a risk factor, whereas overweight was a protective factor for C. difficile infection. Geriatr Gerontol Int 2022; 22: 63-67.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Pneumonia , Idoso , Índice de Massa Corporal , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/epidemiologia , Humanos , Japão/epidemiologia , Pneumonia/complicações , Pneumonia/diagnóstico , Pneumonia/epidemiologia , Estudos Retrospectivos , Fatores de Risco
13.
Biosci Biotechnol Biochem ; 85(4): 824-833, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33589932

RESUMO

At the last stage of the blood coagulation cascade, thrombin plays a central role in the processing of fibrinogen for the polymerization and in the additional activation of Factor XIII for the stable cross-linking of fibrin. In addition, thrombin carries out possible multiple roles via processing or interaction with various functional proteins. Several studies conducted in order to elucidate additional physiological significance are ongoing. To clarify further significance of thrombin and to establish an associated disease model, we characterized the orthologue gene for medaka (Oryzias latipes), a research model fish. Tissue distribution of medaka prothrombin has been immunotechnically analyzed. Furthermore, thrombin-deficient medaka mutants were viably established by utilizing a genome-editing method. The established gene-deficient mutants exhibited retarded blood coagulation even in the heterozygous fish. Taking advantage of their ease of handling, this specific model is useful for further investigation in medical research areas on human coagulation diseases.


Assuntos
Transtornos da Coagulação Sanguínea/genética , Trombina/genética , Animais , Edição de Genes , Modelos Animais , Oryzias , Protrombina/metabolismo , Distribuição Tecidual
14.
Nutrients ; 12(11)2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182514

RESUMO

This study investigated the nutritional factors that are associated with anxiety and depressive symptoms in Japanese middle-aged and elderly women. We conducted a cross-sectional study with 289 study participants aged ≥40 years (mean age = 52.0 ± 6.9 years). Their dietary habits, menopausal status and symptoms, and varied background factors, such as body composition, lifestyle factors, and cardiovascular parameters, were assessed. Their anxiety and depressive symptoms were evaluated using the Hospital Anxiety and Depression Scale (HADS), where scores of 0-7 points, 8-10 points, and 11-21 points on either the anxiety or depression subscales were categorized as mild, moderate, and severe, respectively. The dietary consumption of nutrients was assessed using a brief self-administered diet history questionnaire. The relationships between the moderate-to-severe anxiety/depressive symptoms and the dietary intake of 43 major nutrients were investigated using multivariate logistic regression analyses. After adjusting for age, menopausal status, and the background factors that were significantly related to depressive symptoms, moderate and severe depression was significantly inversely associated with only vitamin B6 (adjusted odds ratio per 10 µg/MJ in vitamin B6 intake = 0.89, 95% confidence interval = 0.80-0.99). A higher intake of vitamin B6 could help relieve depressive symptoms for this population.


Assuntos
Ansiedade/epidemiologia , Depressão/epidemiologia , Suplementos Nutricionais , Vitamina B 6/administração & dosagem , Idoso , Estudos Transversais , Comportamento Alimentar , Feminino , Humanos , Japão/epidemiologia , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Estado Nutricional , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Inquéritos e Questionários
15.
Food Sci Nutr ; 8(8): 4422-4431, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32884722

RESUMO

This study investigated the relationship between subjective forgetfulness and the dietary intake of various nutrients in middle-aged and senior women. A cross-sectional study of the first-visit records of 245 Japanese women aged 40 or over was performed. The severity of subjective forgetfulness was classified according to the Menopausal Health-Related Quality of Life Questionnaire: none and mild ("unforgetful") or moderate and severe ("forgetful"). Dietary consumption of nutrients was estimated using the brief-type self-administered diet history questionnaire. The associations between the severity of subjective forgetfulness and intake of 43 major nutrients were evaluated using multivariate logistic regression analysis separately performed for two age groups: middle-aged (40-54 years, N = 166) and senior (55 years or over, N = 79). No nutrients were found to be significantly associated with subjective forgetfulness in the middle-aged group. In senior women, a significant positive relationship between the intake of copper and forgetfulness was found (adjusted odds ratio per 10 mg/kJ increase in copper intake: 1.25; 95% confidence interval: 1.08-1.50). Thus, high copper intake is positively associated with the severity of forgetfulness in Japanese senior women. Reducing copper consumption could help improve this symptom in this population.

16.
Chem Asian J ; 15(8): 1330-1338, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32083804

RESUMO

The partial fluorination of polycyclic aromatic hydrocarbons often produces a layered crystal packing, where fluorinated aromatic surfaces are stacked over nonfluorinated aromatic surfaces. Herein, we report the synthesis and crystal packing of partially fluorinated [4]helicenes with steric congestion resulting from H and F atoms in the fjord region. F6 -[4]Helicene forms head-to-tail columnar stacks consisting of an alternate arrangement of perfluorinated and nonfluorinated naphthalene moieties. With decreasing fluorine content, aromatic stacking switched from arene-fluoroarene (ArH -ArF ) hetero-stacking to ArH -ArH /ArF -ArF homo-stacking with the help of intermolecular C-H⋅⋅⋅F contacts in the fjord region. As a result, head-to-head columnar stacks appear. Therefore, the conventional ArH -ArF stacking motif is not always applicable to Fn -[4]helicenes with twisted π-surfaces.

17.
Anal Biochem ; 604: 113610, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32014415

RESUMO

By genome analysis, seven homologous genes (orthologues) of human transglutaminases (TGases) have been identified in medaka fish (Oryzias latipes), some of which clearly corresponded to Factor XIII, TG1, and TG2. The enzymatically active-recombinant proteins for these medaka TGases have been successfully produced in bacteria or baculovirus-infected insect cell systems. Specific antibodies have been prepared and used in immunohistochemical analyses to reveal tissue distribution. Furthermore, gene-deficient medaka mutants for the genes encoding Factor XIII and TG1 have been established together with analysis of their phenotypes. Retarded cross-linking of fibrin and higher sensitivity to osmolality are observed when each gene is knocked-out. In this review, we summarize these biochemical features and the phenotypes of these gene-deficient fish.


Assuntos
Proteínas de Peixes/metabolismo , Oryzias/genética , Transglutaminases/metabolismo , Animais , Proteínas de Peixes/genética , Técnicas de Inativação de Genes , Oryzias/metabolismo , Fenótipo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transglutaminases/genética
18.
J Phys Ther Sci ; 31(10): 844-849, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31645817

RESUMO

[Purpose] Integrated volitional control electrical stimulation (IVES) is a type of electrical stimulation therapy that promotes agonist muscle contraction in limbs with motion paralysis. This case study describes the improvement in the paretic hand with stroke hemiplegia, eight years after the onset, with IVES for one month in the extrinsic and intrinsic muscles, including change of mode of stimulation based on the degree of improvement. [Participant and Methods] A 76 year-old male with hemiplegia for eight years. The patient was evaluated for two weeks and performed IVES in the right flexor pollicis brevis, abductor pollicis brevis, and extensor carpi ulnaris with the change of mode of IVES. [Results] The upper limb function improved in a short period of time. The hemiplegia test showed Brunnstrom stages II-III and II-IV for the right upper limb and right hand and fingers, respectively, 28 days after IVES initiation. [Conclusion] After one month of undergoing IVES, the patient showed improvement in hand and finger motor function, which was maintained even after IVES was completed. In this case, there was improvement with a short-term intervention using appropriately combined IVES modes.

19.
FEBS Open Bio ; 9(4): 755-768, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30984549

RESUMO

Liver cirrhosis (LC) is a disease characterized by pathological accumulation and alteration of extracellular matrix (ECM) proteins; the interaction between two such proteins, collagen and vitronectin (VN), is considered to be the key to controlling ECM remodeling in liver cirrhosis. If it is possible to control the modification of oligosaccharides on VN, it may be possible to retard progression of liver cirrhosis. In this study, we examined the relationship between changes in VN glycosylation and activity related to the remodeling of hepatic tissue in human LC and a rat model of LC generated using carbon tetrachloride (CCl4). Plasma concentrations of VN in human LC declined to approximately two-thirds that in normal plasma, but the ratio of active VN, which has collagen-binding activities, increased 2.8 times in LC plasma. In contrast, purified LC-VN exhibited similar binding activities toward type I, IV, and V collagens to those of normal VN. Lectin reactivities and carbohydrate analyses of LC-VN revealed that branching, fucosylation, and sialylation of N-glycans were higher than those of normal VN. On the other hand, the plasma level of rat CCl4-VN increased and the ratio of active molecules to collagen in plasma decreased. Increased fucosylation of LC-VN was not detected in carbohydrates of CCl4-VN. The changes in rat VN due to CCl4 treatment did not correspond to the changes in plasma levels of human VN caused by LC, the ratio of active molecules, or carbohydrate composition, thereby indicating that CCl4-treated rats are not an appropriate model for studying VNs in human LC. Glycosidase treatment of VNs supported the hypothesis that the collagen-binding activity of VN is modulated by alterations of glycosylation during LC, which may contribute to (a) the matrix incorporation of VN and (b) tissue fibrosis.


Assuntos
Colágeno/metabolismo , Glicosilação , Cirrose Hepática/metabolismo , Regeneração Hepática , Vitronectina/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Humanos , Masculino , Ratos , Ratos Wistar
20.
Sci Adv ; 4(10): eaau1199, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30324136

RESUMO

Soluble immunoglobulin M (IgM) forms a pentamer containing a joining (J) chain polypeptide. While IgM pentamer has various immune functions, it also behaves as a carrier of circulating apoptosis inhibitor of macrophage (AIM; also called CD5L) protein that facilitates repair during different diseases. AIM binds to the IgM pentamer solely in the presence of the J chain. Here, using a single-particle negative-stain electron microscopy, we found that the IgM pentamer exhibits an asymmetric pentagon containing one large gap, which is markedly different from the textbook symmetric pentagon model. A single AIM molecule specifically fits into the gap, cross-bridging two IgM-Fc that form the edges of the gap through a disulfide bond at one side and a charge-based interaction at the other side. The discovery of the bona fide shape of the IgM pentamer advances our structural understanding of the pentameric IgM and its binding mode with AIM.


Assuntos
Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/metabolismo , Membrana Celular/metabolismo , Imunoglobulina M/química , Imunoglobulina M/metabolismo , Receptores Imunológicos/química , Receptores Imunológicos/metabolismo , Animais , Membrana Celular/química , Conformação Proteica , Receptores Depuradores
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