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1.
Nature ; 629(8013): 901-909, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38658756

RESUMEN

The liver is the main gateway from the gut, and the unidirectional sinusoidal flow from portal to central veins constitutes heterogenous zones, including the periportal vein (PV) and the pericentral vein zones1-5. However, functional differences in the immune system in each zone remain poorly understood. Here intravital imaging revealed that inflammatory responses are suppressed in PV zones. Zone-specific single-cell transcriptomics detected a subset of immunosuppressive macrophages enriched in PV zones that express high levels of interleukin-10 and Marco, a scavenger receptor that sequesters pro-inflammatory pathogen-associated molecular patterns and damage-associated molecular patterns, and consequently suppress immune responses. Induction of Marco+ immunosuppressive macrophages depended on gut microbiota. In particular, a specific bacterial family, Odoribacteraceae, was identified to induce this macrophage subset through its postbiotic isoallolithocholic acid. Intestinal barrier leakage resulted in inflammation in PV zones, which was markedly augmented in Marco-deficient conditions. Chronic liver inflammatory diseases such as primary sclerosing cholangitis (PSC) and non-alcoholic steatohepatitis (NASH) showed decreased numbers of Marco+ macrophages. Functional ablation of Marco+ macrophages led to PSC-like inflammatory phenotypes related to colitis and exacerbated steatosis in NASH in animal experimental models. Collectively, commensal bacteria induce Marco+ immunosuppressive macrophages, which consequently limit excessive inflammation at the gateway of the liver. Failure of this self-limiting system promotes hepatic inflammatory disorders such as PSC and NASH.


Asunto(s)
Colangitis Esclerosante , Microbioma Gastrointestinal , Inflamación , Hígado , Macrófagos , Enfermedad del Hígado Graso no Alcohólico , Simbiosis , Animales , Femenino , Humanos , Masculino , Ratones , Bacteroidetes/metabolismo , Colangitis Esclerosante/inmunología , Colangitis Esclerosante/microbiología , Colangitis Esclerosante/patología , Microbioma Gastrointestinal/inmunología , Microbioma Gastrointestinal/fisiología , Perfilación de la Expresión Génica , Inflamación/inmunología , Inflamación/microbiología , Inflamación/patología , Interleucina-10/inmunología , Interleucina-10/metabolismo , Hígado/inmunología , Hígado/patología , Hígado/microbiología , Macrófagos/citología , Macrófagos/inmunología , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/inmunología , Enfermedad del Hígado Graso no Alcohólico/microbiología , Enfermedad del Hígado Graso no Alcohólico/patología , Vena Porta , Receptores Inmunológicos/deficiencia , Receptores Inmunológicos/metabolismo , Análisis de la Célula Individual , Simbiosis/inmunología
2.
Nat Commun ; 14(1): 5684, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37735445

RESUMEN

Imagine being in a crowded room with a cacophony of speakers and having the ability to focus on or remove speech from a specific 2D region. This would require understanding and manipulating an acoustic scene, isolating each speaker, and associating a 2D spatial context with each constituent speech. However, separating speech from a large number of concurrent speakers in a room into individual streams and identifying their precise 2D locations is challenging, even for the human brain. Here, we present the first acoustic swarm that demonstrates cooperative navigation with centimeter-resolution using sound, eliminating the need for cameras or external infrastructure. Our acoustic swarm forms a self-distributing wireless microphone array, which, along with our attention-based neural network framework, lets us separate and localize concurrent human speakers in the 2D space, enabling speech zones. Our evaluations showed that the acoustic swarm could localize and separate 3-5 concurrent speech sources in real-world unseen reverberant environments with median and 90-percentile 2D errors of 15 cm and 50 cm, respectively. Our system enables applications like mute zones (parts of the room where sounds are muted), active zones (regions where sounds are captured), multi-conversation separation and location-aware interaction.


Asunto(s)
Acústica , Habla , Humanos , Sonido , Comunicación , Concienciación
3.
Hinyokika Kiyo ; 68(5): 155-159, 2022 05.
Artículo en Japonés | MEDLINE | ID: mdl-35748234

RESUMEN

We describe two cases of locally advanced rectal cancer (LARC) treated with robot-assisted total pelvic exenteration (Ra-TPE) and intracorporeal ileal conduit (ICIC). The first case was in a 71-year-old man with LARC (RbP, T4bN2bM0, cStage IIIc). He was started on bevacizumab+S-1/oxaliplatin therapy in July 2019. In April 2020, he developed Fournier's gangrene due to subcutaneous penetration of rectal cancer. Emergency drainage and colostomy were performed simultaneously, and a percutaneous vesical fistula was created. In May 2020, Ra-TPE and ICIC were performed. Histopathological analysis revealed moderately differentiated tubular adenocarcinoma (ypT3N0, RM0). At postoperative 9 months, thoracoscopic right upper lobectomy was performed for a right metastatic lung tumor. At present, ie, at postoperative 12 months, the patient has been free of recurrence and metastasis, with a carcinoembryonic antigen (CEA) level of 1.4 ng/ml and carcinoma antigen (CA) 19-9 level of 11 U/ml. The second case was in a 61-year-old man with fistula-associated anal cancer (PRb, T4N3M1b, cStage IVb). In April 2019, he was started on FOLFOXIRI+cetuximab therapy. In August 2020, Ra-TPE, ICIC, and transperineal total mesenteric excision were performed. Histopathological analysis revealed adenocarcinoma (ypT4N0, RM0). At postoperative 11 months, thoracoscopic left lower lobectomy was performed for a left metastatic lung tumor. At present, ie, at postoperative 12 months, the patient remains free of recurrence and metastasis, with a CEA level of 7.3 ng/ml and CA19-9 level of 12 U/ml. Ra-TPE, which allows transperineal removal of a specimen, can be performed as a minimally invasive surgery in combination with ICIC.


Asunto(s)
Adenocarcinoma , Neoplasias Pulmonares , Exenteración Pélvica , Neoplasias del Recto , Robótica , Derivación Urinaria , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/cirugía , Anciano , Antígeno Carcinoembrionario , Humanos , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/cirugía
4.
Harmful Algae ; 115: 102230, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35623687

RESUMEN

The genus Gambierdiscus is a marine benthic/epiphytic dinoflagellate that has been investigated worldwide as the causative agent of ciguatera poisoning (CP). In Japan, CP occurs mainly in the subtropical region and sporadically in the temperate region. To understand the mechanism of CP outbreaks in the coastal regions, identifying the species of Gambierdiscus occurring in the regions and determining their toxicity and growth characteristics, such as growth responses to temperature, salinity, and light intensity, are important. Recently, the occurrence of G. silvae in the Japanese temperate and subtropical regions has been revealed through metabarcoding. However, the toxicity and growth characteristics of G. silvae have not yet been investigated. In this study, three strains of Gambierdiscus were isolated from a depth of 30 m in subtropical waters in Japan and were identified as Gambierdiscus silvae based on morphological characteristics and phylogenetic positions. A dichloromethane soluble fraction (DSF) and aqueous methanol soluble fraction (MSF) of the three strains showed high mouse toxicity by intraperitoneal injection, but only the DSF of the three strains showed toxicity by gavage. All strains grew in the range of 17.5-30 °C and salinity range of 25-40, and grew well at 25 °C and salinity 30. The optimal light intensity for growth of the strains was 42.0-83.0 µmol photons/m2/s. These results suggest that G. silvae has the potential to be widely distributed from temperate to subtropical/ regions and in shallow to deep coastal waters of Japan. Understanding the growth characteristics of this species would be useful in predicting the occurrence of this species in Japanese coastal waters. Finally, the results obtained in this study suggest that G. silvae showing high toxicity is one of the causative agents of CP in Japan, and knowledge of this species would be useful in understanding the mechanism of CP outbreaks in Japan.


Asunto(s)
Intoxicación por Ciguatera , Dinoflagelados , Animales , Dinoflagelados/fisiología , Japón , Ratones , Filogenia
5.
J Med Invest ; 69(1.2): 148-151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35466138

RESUMEN

INTRODUCTION: Early prophylactic administration of anticoagulants is recommended in patients with coronavirus disease 2019 (COVID-19). A case of retroperitoneal hemorrhage during inpatient treatment for COVID-19 is reported. CASE PRESENTATION: A 69-year-old man was diagnosed with COVID-19 6 days after symptom onset. After admission for difficulty of breathing, he was treated with steroid pulse therapy, remdesivir, and heparin sodium. On day 16 after admission, his hemoglobin and blood pressure dropped. Computed tomography showed a left retroperitoneal hematoma and multiple areas of extravasation in bilateral iliopsoas muscles. Anticoagulation therapy was stopped, and blood transfusion therapy was chosen by considering poor general condition caused by severe pneumonia. On day 19, the hemoglobin and blood pressure improved, and blood transfusion was stopped. However, he died on day 25 due to pneumonia. CONCLUSION: When retroperitoneal hemorrhage occurs as a complication of COVID-19, appropriate treatment decision, transcatheter arterial embolization or conservative treatment, should be chosen based on patient's condition. J. Med. Invest. 69 : 148-151, February, 2022.


Asunto(s)
COVID-19 , Anciano , Anticoagulantes/uso terapéutico , COVID-19/complicaciones , Hemoglobinas , Hemorragia/etiología , Hemorragia/terapia , Heparina , Humanos , Masculino
6.
Sci Technol Adv Mater ; 22(1): 748-757, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34512178

RESUMEN

It has been empirically known that the coercivity of rare-earth permanent magnets depends on the size and shape of fine particles of the main phase in the system. Also, recent experimental observations have suggested that the atomic-scale structures around the grain-boundaries of the fine particles play a crucial role to determine their switching fields. In this article, we review a theoretical attempt to describe the finite temperature magnetic properties and to evaluate the reduction of the switching fields of fine particles of several rare-earth permanent magnetic materials based on an atomistic spin model that is constructed using first-principles calculations. It is shown that, over a wide temperature range, the spin model gives a good description of the magnetization curves of rare-earth intermetallic compounds such as R 2Fe14B (R= Dy, Ho, Pr, Nd, Sm) and SmFe12. The atomistic spin model approach is also used to describe the local magnetic anisotropy around the surfaces of the fine particles, and predicts that the rare-earth ions may exhibit planar magnetic anisotropy when they are on the crystalline-structure surfaces of the particles. The dynamical simulation of the atomistic spin model and the corresponding micromagnetic simulation show that the planar surface magnetic anisotropy causes a reduction in the switching field of fine particles by approximately 20-30%, which may be relevant to the atomic-scale surface effects found in the experimental studies.

7.
Artículo en Japonés | MEDLINE | ID: mdl-33612693

RESUMEN

PURPOSE: Because of the promotion of cancer screening, the number of patients with lung cancer detected at the early stage has increased. However, it was reported that 30-40% of the lung cancer patients at stage I relapsed. If the recurrence risk can be accurately predicted, it is possible to give medical care for improving the prognosis of lung cancer patients. The purpose of this study was to develop a method for the prediction of recurrence risk of patients with lung cancer by using survival analysis of radiomics approach. METHOD: A public database was used in this study. Fifty patients (25 recurrences and 25 censored cases) classified as stage I or II were selected and their pretreatment computed tomography (CT) images were obtained. First, we selected one slice containing the largest tumor area and manually segmented the tumor regions. We subsequently calculated 367 radiomic features such as tumor size, shape, CT values, and texture. Radiomic features were selected by using least absolute shrinkage and selection (Lasso). Cox regression model and random survival forest (RSF) with the selected radiomic features were used for estimating the recurrence functions of fifty patients. RESULT: The experimental result showed that average area under the curve (AUC) values of Cox regression model and RSF for the prediction accuracy were 0.81 and 0.93, respectively. CONCLUSION: Since our scheme can predict recurrence risk of patients with lung cancer by using non-invasive image examinations, it would be useful for the selection of treatment and the follow-up after the treatment.


Asunto(s)
Neoplasias Pulmonares , Recurrencia Local de Neoplasia , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Pronóstico , Análisis de Supervivencia , Tomografía Computarizada por Rayos X
8.
J Antibiot (Tokyo) ; 74(5): 359-362, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33469193

RESUMEN

In our screening program for new biologically active compounds, a new polyene macrolide, lavencidin (1), along with known compound RKGS-A2215A (2), was isolated from the fermentation broth of Streptomyces lavendulae FRI-5 by changing the composition of liquid medium normally used for the strain. Their structures were elucidated by spectral methods (high-resolution fast-atom bombardment mass spectrometry (HRFABMS) and nuclear magnetic resonance (NMR)). Compound 1 includes a conjugated pentaene moiety together with six hydroxy groups and a carboxylic acid as a side chain. Lavencidin (1) showed moderate growth-inhibitory activity against yeast and was cytotoxic against human cancer cell lines with low-micromolar IC50 values.


Asunto(s)
Antifúngicos/farmacología , Macrólidos/química , Macrólidos/farmacología , Streptomyces/metabolismo , Levaduras/efectos de los fármacos , Antifúngicos/química , Línea Celular Tumoral , Humanos , Macrólidos/metabolismo , Espectroscopía de Resonancia Magnética
10.
Chem Commun (Camb) ; 54(63): 8761-8764, 2018 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-30033470

RESUMEN

A trifluoromethyl analogue of diethylaminosulfur trifluoride (CF3-DAST)-induced deacylative trifluoromethylthiolation of cyclic 1,3-diketones, lactams, and lactones that provides cyclic α-trifluoromethylthioketones, lactams, and lactones is reported. To the best of our knowledge, this method represents the first example of the trifluoromethylthiolation of lactams. A corresponding deacylative pentafluorophenylthiolation using a pentafluorophenyl analogue of diethylaminosulfur trifluoride (C6F5-DAST) was also attempted.

11.
Chem Commun (Camb) ; 54(49): 6272-6275, 2018 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-29850758

RESUMEN

Herein we report that a preferable inhibition of the nucleation phase of Aß42, related to the formation of toxic oligomers, by triterpenoids from medicinal herbs originates from a salt bridge of their carboxy groups with Lys16 and 28 in Aß42. Such a direct interaction targeting the monomer, dimer, and trimer suppressed further oligomerization. In contrast, the corresponding congeners without carboxy groups failed to do so.


Asunto(s)
Péptidos beta-Amiloides/química , Ácidos Carboxílicos/farmacología , Fármacos Neuroprotectores/farmacología , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacología , Fragmentos de Péptidos/química , Antraquinonas/química , Antraquinonas/farmacología , Ácidos Carboxílicos/química , Línea Celular Tumoral , Humanos , Lisina/química , Fármacos Neuroprotectores/química , Ácido Oleanólico/química , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacología , Multimerización de Proteína , Triterpenos/química , Triterpenos/farmacología
12.
Org Lett ; 18(24): 6404-6407, 2016 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-27978672

RESUMEN

Trifluoromethyl diethylaminosulfur difluoride (CF3-DAST) was found to be an efficient reagent for the trifluoromethylthiolation of α-methylene-ß-keto esters providing α-trifluoromethylthio-ß-keto esters in good to high yields. α-Methylene-ß-keto sulfones were also accepted as substrates by CF3-DAST to furnish the corresponding α-trifluoromethylthio compounds. This strategy can be extended to perfluoroalkylthiolation reactions using perfluoroethyl-DAST (C2F5-DAST) and perfluoropropyl-DAST (C3F7-DAST).

13.
J Nat Prod ; 79(10): 2521-2529, 2016 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-27700077

RESUMEN

Oligomers of the 42-mer amyloid-ß protein (Aß42), rather than fibrils, cause synaptic dysfunction in the pathology of Alzheimer's disease (AD). The nucleation phase in a nucleation-dependent aggregation model of Aß42 is related to the formation of oligomers. Uncaria rhynchophylla is one component of "Yokukansan", a Kampo medicine, which is widely used for treating AD symptoms. Previously, an extract of U. rhynchophylla was found to reduce the aggregation of Aß42, but its active principles have yet to be identified. In the present work, uncarinic acid C (3) was identified as an inhibitor of Aß42 aggregation that is present in U. rhynchophylla. Moreover, compound 3 acted as a specific inhibitor of the nucleation phase of Aß42 aggregation. Compound 3 was synthesized from saponin A (10), an abundant byproduct of rutin purified from Uncaria elliptica. Comprehensive structure-activity studies on 3 suggest that both a C-27 ferulate and a C-28 carboxylic acid group are required for its inhibitory activity. These findings may aid the development of oligomer-specific inhibitors for AD therapy.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Triterpenos/síntesis química , Triterpenos/farmacología , Uncaria/química , Supervivencia Celular , Medicamentos Herbarios Chinos , Humanos , Japón , Estructura Molecular , Neuronas/metabolismo , Fragmentos de Péptidos , Rifamicinas , Relación Estructura-Actividad , Triterpenos/química
14.
Clin Exp Rheumatol ; 32(4 Suppl 84): S9-19, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24237878

RESUMEN

OBJECTIVES: To investigate the pathophysiology of Behçet's disease (BD) and find biomarkers for the disease, we analysed protein profiles of peripheral blood mononuclear cells (PBMCs). METHODS: Proteins, extracted from PBMCs, were comprehensively analysed in 16 patients with BD, 16 patients with rheumatoid arthritis (RA), 12 patients with Crohn's disease (CD), and 16 healthy control subjects (HC) by 2-dimensional differential gel electrophoResis (2D-DIGE). Differently expressed proteins were identified by mass spectrometry. RESULTS: 563 protein spots were detected. We completely discriminated between the BD and HC groups, between the BD and RA groups, and between the BD and CD groups by multivariate analysis of intensity of 23, 35, and 1 spots, respectively. The spots contributing to the differences included proteins related to cytoskeleton, transcription/translation, T cell activation, bone turnover, regulating apoptosis, and microbial infection. Intensity of 3 spots (tyrosine-protein phosphatase non-receptor type 4, threonine synthase-like 2, and ß-actin) provided area under the receiver operating characteristic curves (AUROC) of 0.889 for discrimination between the BD group and the non-BD groups. Informatively, intensity of the above 1 spot completely discriminated the CD group from the other groups (AUROC 1.000). This spot, identified as ß-actin, had different pI from the above ß-actin-spot probably due to different post-translational modification. CONCLUSIONS: PBMC protein profiles, especially the profile of the 3 spots, would be candidate biomarkers for BD. The latter ß-actin subtype would be useful for discriminating inflammatory bowel diseases from BD and other diseases. The identified proteins may play important roles in the pathophysiology of BD.


Asunto(s)
Síndrome de Behçet/diagnóstico , Síndrome de Behçet/metabolismo , Leucocitos Mononucleares/metabolismo , Proteómica/métodos , Electroforesis Bidimensional Diferencial en Gel/métodos , Adolescente , Adulto , Anciano , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/inmunología , Artritis Reumatoide/metabolismo , Síndrome de Behçet/inmunología , Biomarcadores/metabolismo , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/metabolismo , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad
15.
Int J Rheum Dis ; 15(2): 169-78, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22462420

RESUMEN

AIM: To elucidate the pathophysiology of rheumatoid arthritis (RA) as well as osteoarthritis (OA), we analyzed protein profiles of bone marrow-derived adherent cells (BMACs) from patients with these diseases. METHODS: Proteins, extracted from BMACs from three RA and three OA patients, were comprehensively analyzed by 2-dimensional differential image gel electrophoresis (2D-DIGE). Then a part of the detected proteins, differently expressed between the two diseases, were identified by mass spectrometric analysis. RESULTS: 2D-DIGE analysis detected more than 1600 protein spots in both RA and OA BMACs. Out of these, expression of 340 spots was significantly altered between the diseases (more than 1.5-fold: RA > OA, 26 spots; OA > RA, 314 spots; P < 0.05). Eleven protein spots the intensity of which were significantly altered by more than 2.0-fold were identified, which included vimentin and annexin A5 as increased proteins in RA rather than in OA. As increased proteins in OA compared to RA, alpha chain of collagen VI, a membrane anchor for acetylcholine esterase, heat shock protein 27, caldesmon and cytoskeletal proteins, such as beta actin and alpha tubulin, were identified. CONCLUSIONS: We here report different protein profiles of BMACs between RA and OA for the first time. BMACs possessing differently expressed proteins may be involved in the pathophysiology of the two diseases.


Asunto(s)
Artritis Reumatoide/metabolismo , Células de la Médula Ósea/metabolismo , Médula Ósea/metabolismo , Osteoartritis de la Cadera/metabolismo , Proteínas/metabolismo , Proteómica , Anciano , Artritis Reumatoide/patología , Artritis Reumatoide/fisiopatología , Médula Ósea/patología , Células de la Médula Ósea/patología , Adhesión Celular , Electroforesis en Gel Bidimensional , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/patología , Osteoartritis de la Cadera/fisiopatología , Mapeo Peptídico , Proteínas/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
16.
Phys Rev Lett ; 107(25): 256403, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22243096

RESUMEN

We investigate the correlation effect in the quasi-one-dimensional electron-hole (e-h) system under thermal equilibrium. A self-consistent screened T-matrix approximation developed here enables the description of an e-h pair under any ionization ratio, the portion of quasielectrons or quasiholes moving almost freely. Our phase diagram on the ionization ratio provides a unified description of exciton Mott physics from the low-density exciton gas towards the high-density electron-hole plasma, and predicts a first order transition at low temperature. The interband optical absorption-gain spectra are also evaluated, which succeeded in explaining semiquantitatively all aspects of the recent experimental observations in the strongly photoexcited quantum wires.

17.
Phys Rev Lett ; 103(3): 036401, 2009 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-19659299

RESUMEN

We investigate the quantum phase transitions in the half-filled Hubbard model on the triangular lattice by means of the path-integral renormalization group method with a new iteration and truncation scheme proposed recently. It is found for a cluster of 36 sites that as the Hubbard interaction U increases, the paramagnetic metallic state undergoes a first-order phase transition to a nonmagnetic insulating (NMI) state at Uc1 approximately 7.4t, which is followed by another first-order transition to a 120 degrees Néel ordered state at Uc2 approximately 9.2t, where t is the transfer integral. The size dependence of the results is also addressed. Our results suggest the existence of the intermediate NMI phase and resolve some controversial arguments on the nature of the previously proposed quantum phase transitions.

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