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1.
Nature ; 599(7885): 458-464, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34325466

RESUMO

Centenarians have a decreased susceptibility to ageing-associated illnesses, chronic inflammation and infectious diseases1-3. Here we show that centenarians have a distinct gut microbiome that is enriched in microorganisms that are capable of generating unique secondary bile acids, including various isoforms of lithocholic acid (LCA): iso-, 3-oxo-, allo-, 3-oxoallo- and isoallolithocholic acid. Among these bile acids, the biosynthetic pathway for isoalloLCA had not been described previously. By screening 68 bacterial isolates from the faecal microbiota of a centenarian, we identified Odoribacteraceae strains as effective producers of isoalloLCA both in vitro and in vivo. Furthermore, we found that the enzymes 5α-reductase (5AR) and 3ß-hydroxysteroid dehydrogenase (3ß-HSDH) were responsible for the production of isoalloLCA. IsoalloLCA exerted potent antimicrobial effects against Gram-positive (but not Gram-negative) multidrug-resistant pathogens, including Clostridioides difficile and Enterococcus faecium. These findings suggest that the metabolism of specific bile acids may be involved in reducing the risk of infection with pathobionts, thereby potentially contributing to the maintenance of intestinal homeostasis.


Assuntos
Bactérias/metabolismo , Vias Biossintéticas , Centenários , Microbioma Gastrointestinal , Ácido Litocólico/análogos & derivados , Ácido Litocólico/biossíntese , 3-Hidroxiesteroide Desidrogenases/metabolismo , Idoso de 80 Anos ou mais , Animais , Antibacterianos/biossíntese , Antibacterianos/metabolismo , Bactérias/classificação , Bactérias/enzimologia , Bactérias/isolamento & purificação , Colestenona 5 alfa-Redutase/metabolismo , Fezes/química , Fezes/microbiologia , Feminino , Bactérias Gram-Positivas/metabolismo , Humanos , Ácido Litocólico/metabolismo , Masculino , Camundongos , Simbiose
2.
Nature ; 565(7741): 600-605, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30675064

RESUMO

There is a growing appreciation for the importance of the gut microbiota as a therapeutic target in various diseases. However, there are only a handful of known commensal strains that can potentially be used to manipulate host physiological functions. Here we isolate a consortium of 11 bacterial strains from healthy human donor faeces that is capable of robustly inducing interferon-γ-producing CD8 T cells in the intestine. These 11 strains act together to mediate the induction without causing inflammation in a manner that is dependent on CD103+ dendritic cells and major histocompatibility (MHC) class Ia molecules. Colonization of mice with the 11-strain mixture enhances both host resistance against Listeria monocytogenes infection and the therapeutic efficacy of immune checkpoint inhibitors in syngeneic tumour models. The 11 strains primarily represent rare, low-abundance components of the human microbiome, and thus have great potential as broadly effective biotherapeutics.


Assuntos
Adenocarcinoma/imunologia , Adenocarcinoma/terapia , Bactérias/classificação , Linfócitos T CD8-Positivos/imunologia , Microbioma Gastrointestinal/imunologia , Listeriose/prevenção & controle , Simbiose/imunologia , Adenocarcinoma/patologia , Animais , Antígenos CD/metabolismo , Bactérias/imunologia , Bactérias/isolamento & purificação , Linfócitos T CD8-Positivos/citologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Fezes/microbiologia , Feminino , Voluntários Saudáveis , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Cadeias alfa de Integrinas/metabolismo , Interferon gama/biossíntese , Interferon gama/imunologia , Listeria monocytogenes/imunologia , Listeriose/imunologia , Listeriose/microbiologia , Masculino , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Opt Express ; 32(6): 10265-10273, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571242

RESUMO

Measurement applications in optical fields require arbitrary spectro-temporal pulse shaping. However, conventional pulse-shaping algorithms are limited to controlling only the shape of the temporal intensity waveform. To overcome this limitation, we introduce the concept of short-time Fourier transformation into the conventional iterative Fourier transform algorithm, enabling it to introduce spectro-temporal constraints using a spectrogram image as a target. We numerically demonstrate that the proposed algorithm can find an appropriate spectral phase modulation pattern to realize arbitrarily controlled spectro-temporal pulse waveforms by testing the algorithm with different spectro-temporal multi-pulse waveforms. The algorithm benefits from reducing computational costs for generating spectro-temporal waveforms.

4.
Bioorg Med Chem ; 100: 117602, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38324946

RESUMO

Moyamoya disease (MMD) is a cerebrovascular disease which is characterized by the chronic progression of steno-occlusive changes at the terminal portion of internal carotid arteries and the development of "moyamoya vessels." Dysregulation of the extracellular matrix is regarded as a key pathophysiology underlying unique vascular remodeling. Here, we measured the concentration of elastin crosslinkers desmosine and isodesmosine in the plasma of MMD patients. We aimed to reveal its diagnostic values of desmosines in the progression of steno-occlusive lesions. The concentrations of plasma desmosines were determined by liquid chromatography-tandem mass spectrometry. The temporal profiles of steno-occlusive lesions on magnetic resonance angiography were retrospectively evaluated, and the correlation between the progression of steno-occlusive changes in intracranial arteries and plasma desmosines concentrations was further analyzed. Plasma desmosines were significantly higher in MMD patients with disease progression compared to MMD patients without disease progression. Also, the incidence of disease progression was higher in MMD patients with plasma desmosines levels over limit of quantitation (LOQ) than those with plasma desmosines levels below LOQ. In conclusion, plasma desmosines could be potential biomarkers to predict the progression of steno-occlusive changes in MMD patients.


Assuntos
Doença de Moyamoya , Humanos , Prognóstico , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/patologia , Desmosina/análise , Estudos Retrospectivos , Tecido Elástico/química , Tecido Elástico/patologia , Progressão da Doença
5.
Dig Dis Sci ; 69(3): 851-869, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244124

RESUMO

AIM: We investigated the von Willebrand factor to ADAMTS13 ratio (von Willebrand factor [VWF]:Ag/ADAMTS13:AC) as a potential biomarker for the outcomes of acute kidney injury (AKI) in liver cirrhosis (LC). METHODS: This retrospective cross-sectional study included patients with LC who developed AKI (AKI group: n = 91) and patients with LC who did not develop AKI [non-AKI (NAKI) group, n = 91] as a control group. Plasma levels of the von Willebrand factor antigen (Ag) and ADAMTS13 activity (AC) were measured in patients with AKI or NAKI. Moreover, risk factors for onset of AKI, AKI-associated 90-day mortality, and poor AKI treatment response were identified. RESULTS: The AKI group had a significantly higher VWF:Ag/ADAMTS13:AC than the NAKI group. Values of VWF:Ag/ADAMTS13:AC ≥ 5.7 were identified as risk factors for AKI onset in patients with LC (odds ratio [OR] 2.56; 95% CI 1.26-4.99; p < 0.001). Among patients with AKI, values of VWF:Ag/ADAMTS13:AC ≥ 9.0 were identified as risk factors for 90-day mortality (OR 6.83; 95% CI 2.32-20.10; p < 0.001). Cumulative survival was significantly lower in those with high (≥ 9.0) than in those with low (< 9.0) VWF:Ag/ADAMTS13:AC. Furthermore, values of VWF:Ag/ADAMTS13:AC ≥ 7.4 were identified as risk factors for poor treatment response (OR 4.2; 95% CI 1.39-12.70; p < 0.001). The treatment response rates were significantly higher in those with low (< 7.4) VWF:Ag/ADAMTS13:AC than in those with high (≥ 7.4) VWF:Ag/ADAMTS13:AC. CONCLUSION: VWF:Ag/ADAMTS13:AC potentially predicts the onset, prognosis, and treatment response of AKI in patients with LC.


Assuntos
Injúria Renal Aguda , Fator de von Willebrand , Humanos , Estudos Retrospectivos , Estudos Transversais , Cirrose Hepática/diagnóstico , Biomarcadores , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Proteína ADAMTS13
6.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473925

RESUMO

Portal vein thrombosis (PVT), one of the most prevalent hepatic vascular conditions in patients with liver cirrhosis (LC), is associated with high mortality rates. An imbalance between a disintegrin-like metalloproteinase with thrombospondin type-1 motifs 13 (ADAMTS-13) enzyme and von Willebrand factor (VWF) is responsible for hypercoagulability, including spontaneous thrombus formation in blood vessels. Herein, we aimed to identify potential prognostic and diagnostic biomarkers in Japanese patients with LC and PVT. In total, 345 patients were divided into two groups: 40 patients who developed PVT (PVT group) and 305 who did not develop PVT (NPVT group). Among the 345 patients with LC, 81% (279/345) were deemed ineligible due to the presence of preventive comorbidities, active or recent malignancies, and organ dysfunction. The remaining 66 patients were divided into two groups: the PVT group (n = 33) and the NPVT group (n = 33). Plasma ADAMTS-13 activity (ADAMTS-13:AC) and the vWF antigen (VWF:Ag) were measured using enzyme-linked immunosorbent assays. Contrast-enhanced, three-dimensional helical computed tomography (CT) was used to detect and characterize PVT. ADAMTS-13:AC was significantly lower in the PVT group than in the NPVT group. No significant differences in plasma vWF:Ag or liver stiffness were observed between the two groups. ADAMTS-13:AC of <18.8 was an independent risk factor for PVT on multivariate analyses (odds ratio: 1.67, 95% confidence interval: 1.21-3.00, p < 0.002). The receiver operating characteristic analysis of ADAMTS-13:AC revealed an area under the curve of 0.913 in PVT detection. Patients with PVT having ADAMTS-13:AC ≥18.8 (n = 17) had higher albumin levels and better prognoses than those with ADAMTS-13:AC <18.8 (n = 16). No significant correlations of ADAMTS-13:AC levels with either fibrin degradation product or D-dimer levels were observed. ADAMTS-13:AC levels could be potential diagnostic and prognostic biomarkers for PVT in Japanese patients with LC.


Assuntos
Trombose Venosa , Fator de von Willebrand , Humanos , Fator de von Willebrand/metabolismo , Veia Porta/metabolismo , Proteína ADAMTS13 , Prognóstico , Japão , Cirrose Hepática/patologia , Trombose Venosa/complicações , Biomarcadores
7.
J Vasc Surg ; 77(1): 114-121.e2, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35985566

RESUMO

OBJECTIVE: The objective of this study was to investigate the mid-term outcomes of embolization procedures for type II endoleak after endovascular abdominal aortic repair, and clarify the risk factors for aneurysm enlargement after embolization procedures. METHODS: This was a retrospective multicenter registry study enrolling patients who underwent embolization procedures for type II endoleaks after EVAR from January 2012 to December 2018 at 19 Japanese centers. The primary end point was the rate of freedom from aneurysm enlargement, more than 5 mm in the aortic maximum diameter, after an embolization procedure. Demographic, procedural, follow-up, and laboratory data were collected. Continuous variables were summarized descriptively, and Kaplan-Meier analyses and a Cox regression model were used for statistical analyses. RESULTS: A total of 315 patients (248 men and 67 women) were enrolled. The average duration from the initial embolization procedure to the last follow-up was 31.6 ± 24.6 months. The rates of freedom from aneurysm enlargement at 3 and 5 years were 55.4 ± 3.8% and 37.0 ± 5.2%, respectively. A multivariate analysis revealed that a larger aortic diameter at the initial embolization procedure and the presence of a Moyamoya endoleak, defined as heterogeneous contrast opacity with an indistinct faint border, were associated with aneurysm enlargement after embolization management. CONCLUSIONS: The embolization procedures were generally ineffective in preventing further expansion of abdominal aortic aneurysms in patients with type II endoleaks after EVAR, especially in patients with a large abdominal aortic aneurysm and/or a presence of a Moyamoya endoleak.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Embolização Terapêutica , Procedimentos Endovasculares , Masculino , Humanos , Feminino , Endoleak/diagnóstico por imagem , Endoleak/etiologia , Endoleak/terapia , Resultado do Tratamento , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Fatores de Tempo , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/complicações , Fatores de Risco , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Estudos Retrospectivos
8.
Respir Res ; 24(1): 283, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964338

RESUMO

BACKGROUND: Multiple prolonged symptoms are observed in patients who recover from acute coronavirus disease 2019 (COVID-19), defined as long COVID. Cough and sputum are presented by patients with long COVID during the acute and post-acute phases. This study aimed to identify specific risk factors for cough and sputum in patients with long COVID. METHODS: Hospitalized patients with COVID-19 aged 18 years were enrolled in a multicenter cohort study at 26 medical institutions. Clinical data during hospitalization and patient-reported outcomes after discharge were collected from medical records, paper-based questionnaires, and smartphone apps. RESULTS: At the 3-, 6-, and 12-month follow-ups, there were no differences in the incidence rates of wet and dry coughs. In contrast, the proportion of patients presenting sputum without coughing increased over time compared to those with sputum and coughing. Univariate analyses of cough and sputum at all follow-up visits identified intermittent mandatory ventilation (IMV), smoking, and older age as risk factors for prolonged symptoms. At the 12-month follow-up, persistent cough and sputum were associated with the characteristics of severe COVID-19 based on imaging findings, renal and liver dysfunction, pulmonary thromboembolism, and higher serum levels of LDH, KL-6, and HbA1C. The Kaplan-Meier curves showed that the severity of acute COVID-19 infection was correlated with prolonged cough and sputum production. Multivariable logistic regression analysis showed that IMV ventilator management were independent risk factors for prolonged cough and sputum at 12 months. CONCLUSIONS: In a Japanese population with long COVID, prolonged cough and sputum production were closely associated with severe COVID-19. These findings emphasize that a preventive approach including appropriate vaccination and contact precaution and further development of therapeutic drugs for COVID-19 are highly recommended for patients with risk factors for severe infection to avoid persistent respiratory symptoms.


Assuntos
COVID-19 , Humanos , Síndrome de COVID-19 Pós-Aguda , Escarro , SARS-CoV-2 , Estudos de Coortes , Japão/epidemiologia , Tosse/diagnóstico , Tosse/epidemiologia
9.
J Immunol ; 207(9): 2223-2234, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34588217

RESUMO

The pathogenesis of allergic contact dermatitis (ACD) requires the activation of Ag-specific T cells, including effector and regulatory T cells. The differentiation and function of these T cells is epigenetically regulated through DNA methylation and histone modifications. However, the roles of altered histone H3K27 methylation in T cells in the development of ACD remain unknown. Two types of histone H3K27 demethylases, Utx and Jmjd3, have been reported in mammals. To determine the role of the histone H3K27 demethylase expression of T cells in the development of ACD, we generated T cell-specific, Utx-deficient (Utx KO) mice or Jmjd3-deficient (Jmjd3 KO) mice. Unlike control mice, Utx KO mice had severer symptoms of ACD, whereas Jmjd3 KO mice showed symptoms identical to those in control mice. In Utx KO mice with ACD, the massive infiltration of myeloid cells, including neutrophils and dendritic cells, has been observed. In addition, the expression of proinflammatory cytokines in CD4+ T cells of the draining lymph nodes (LNs) and in CD8+ T cells of the skin was increased in Utx KO mice, whereas the ratio of Foxp3+ regulatory CD4+ T cells to Foxp3- conventional CD4+ T cells was decreased in both the draining LNs and the skin of Utx KO mice with ACD. Furthermore, Foxp3+ regulatory CD4+ T cells of Utx KO mice with ACD expressed a decreased level of CCR4 (a skin-tropic chemokine receptor) in comparison with control. Thus, in CD4+ T cells, Utx could potentially be involved in the regulation of the pathogenesis of ACD.


Assuntos
Dermatite de Contato/imunologia , Histona Desmetilases/metabolismo , Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Pele/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Histona Desmetilases/genética , Histonas/genética , Humanos , Mediadores da Inflamação/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Camundongos , Camundongos Knockout , Receptores CCR4/metabolismo
10.
Hepatol Res ; 53(8): 713-722, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37050844

RESUMO

AIM: This study aimed to elucidate a surrogate marker of sarcopenia in patients with liver cirrhosis (LC). METHODS: A total of 424 patients were assessed for handgrip strength (HGS) and skeletal muscle index (SMI). They were divided into two groups: sarcopenia (Group S; n = 80) and nonsarcopenia (Group NS; n = 344). RESULTS: Group S showed significantly lower HGS, SMI, and hemoglobin (Hb) levels in males and female patients, and lower serum levels of albumin, cholinesterase, and zinc (all p < 0.001), along with significantly higher serum levels of procollagen type III-N-peptide and type IV collagen 7S-domain (p < 0.001 and p < 0.0017) than Group NS. The risk factors for sarcopenia were age 65 years or older, female gender, Child-Pugh class C, and Hb levels <10.9 g/dL in women and <12.4 g/dL in men (p = 0.012, p < 0.001, p = 0.031, and p < 0.001, respectively). Significant positive correlations were found between the Hb level and the SMI and HGS (r = 0.4, p < 0.001 and r = 0.4, p < 0.001, respectively). Sarcopenia, low HGS, and low SMI were significantly associated with overall survival in patients with LC (all p < 0.001). The predictive accuracy of Hb levels for predicting sarcopenia was significantly higher than for predicting SMI and tended to be higher than for predicting HGS (p = 0.014 and p = 0.059, respectively). CONCLUSION: Hemoglobin levels are predictive of sarcopenia in patients with LC and warrants further investigation as a biomarker for sarcopenia in LC.

11.
J Chem Ecol ; 49(7-8): 397-407, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378686

RESUMO

An electroantennogram (EAG) technique compared the antennal olfactory responses by both sexes of eight Japanese Papilio species with known host plants in laboratory experiments. Papilio species were collected from Honshû and Kyûshû (Japanese islands). The behavioral responses to volatile leaf substances from Citrus deliciosa, Zanthoxylum ailanthoides, Phellodendron amurense, Orixa japonica, and Foeniculum vulgare were examined in laboratory experiments. Individual EAG reactions were recorded. The results were very similar to the empirical field observations. The electrophysiological results of both sexes showed that the volatile substances released from non-preferred plants mainly elicited more significant EAG responses than the volatile substances from preferred host plants. Moreover, we performed behavioral experiments using eight female butterflies and their responses to five host plant species. An association between host plant selection behavior and taxonomical classification exists within the Papilio genus. The EAG responses were small when exposed to the plants with high scores in the behavioral experiments. Host plant preference patterns seem to be related to the volatile substances within the host plants. The butterflies responded to Linalool in both the behavioral and electrophysiological experiments.


Assuntos
Borboletas , Animais , Feminino , Masculino , Monoterpenos Acíclicos , Borboletas/fisiologia , Plantas , Olfato/fisiologia
12.
Pediatr Int ; 65(1): e15599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37551656

RESUMO

BACKGROUND: Very-low-birthweight (VLBW) infants can experience severe intraventricular hemorrhage (IVH) that can lead to life-long disability by impairing neurodevelopment. The aim of this study was to identify the risk and protective factors for severe IVH in VLBW infants. METHODS: A retrospective, cross-sectional review of VLBW infants born at 22-28 weeks' gestation between January 2003 and December 2012 and listed in the Database of Neonatal Research Network in Japan was performed using a statistical model incorporating an odds ratio (OR) and medical center variation as a center variance ratio (CVR). A two-dimensional analysis using a combination of OR and the CVR described evolving measures of a clinical trial (for OR > 1) and standardization (for CVR > 1) concerning a factor of interest. RESULTS: The noteworthy significant protective factors were antenatal steroids (ANS) with and without premature rupture of membrane (OR: 0.43, CVR: 1.08, and OR: 0.68, CVR: 1.14, respectively) and the number of neonatal beds (OR: 0.94, CVR: 0.99) and staff nurses per neonatal bed (OR: 0.89, CVR: 0.99). CONCLUSIONS: Active promotion of ANS administration and consolidation of perinatal medical centers can mitigate the development of severe IVH in VLBW infants.


Assuntos
Doenças do Prematuro , Recém-Nascido Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/etiologia , Estudos Transversais , Idade Gestacional , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/etiologia , Recém-Nascido de muito Baixo Peso , Estudos Retrospectivos
13.
Kyobu Geka ; 76(7): 518-522, 2023 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-37475094

RESUMO

The subxiphoid approach in thymectomy provides better visibility around the left brachiocephalic vein than the lateral thoracic approach. Robot-assisted thoracoscopic surgery is easier to parform than video- assisted thoracoscopic surgery for surgery of the upper mediastinum, because the forceps can be moved with many joints. Robot-assisted thymectomy using the subxiphoid approach may be less traumatic and less invasive than median sternotomy. We must continue to devise surgical procedures to make oncologically curative surgery more minimally invasive.


Assuntos
Neoplasias do Mediastino , Robótica , Humanos , Neoplasias do Mediastino/cirurgia , Cirurgia Torácica Vídeoassistida , Mediastino , Procedimentos Cirúrgicos Minimamente Invasivos , Timectomia/métodos
14.
Kyobu Geka ; 76(10): 834-839, 2023 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-38056846

RESUMO

This article describes the perioperative complications, perioperative risk assessment, and perioperative management of patients with chronic obstructive pulmonary disease (COPD) and interstitial lung disease, especially idiopathic pulmonary fibrosis( IPF), which are the leading diseases in respiratory dysfunction. In COPD, testing for forced expiratory volume during the first second and pulmonary diffusing capacity is important and an algorithm for testing has been presented by the Japanese Association for Chest Surgery. Acute exacerbation of IPF is the leading cause of postoperative mortality in Japan, and risk factors are being analyzed. To reduce the occurrence of postoperative complications, it is important to carry out a risk assessment, select appropriate surgical strategy, and implement a well-planned perioperative management.


Assuntos
Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Doença Pulmonar Obstrutiva Crônica , Humanos , Fibrose Pulmonar Idiopática/complicações , Fibrose Pulmonar Idiopática/epidemiologia , Doenças Pulmonares Intersticiais/epidemiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Fatores de Risco , Medição de Risco , Estudos Retrospectivos
15.
Opt Express ; 30(9): 14851-14872, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473220

RESUMO

We propose a learning-based digital back propagation (LDBP) technique that addresses self-phase modulation (SPM) and cross-phase modulation (XPM) of a wavelength-division multiplexed (WDM) optical signal. The LDBP has a structure defined for each of the individual channels of a WDM signal, and connections between the channels address the XPM to effectively compensate for nonlinear waveform distortion of the signal in long-distance optical transmission systems. We attempt to optimize the limited number of parameters used in the structure such as the dispersion, nonlinear coefficient, and walkoff parameter to compensate for the nonlinear phase shift induced by the XPM. We derive equations to update the parameters through an iterative process based on the stochastic gradient descent algorithm. We verify the effectiveness of the proposed LDBP technique through a transmission experiment that uses an 11-channel WDM, 32-Gbaud, dual-polarization 16 quadrature amplitude modulation (QAM), and probabilistically shaped (PS) 64QAM signals. With the focus on the LDBP with a 1-step/span configuration, we operate the learning process using the received 16QAM signal in the experiment. We confirmed the successful convergence of particular parameters of the model of the transmission line after the developed learning procedure. We apply the LDBP with fixed optimized parameters to the received waveforms of the PS-64QAM signals and compare the performance with some DBPs. We observed that the proposed LDBP technique that considers XPM with 1-step/span configuration exhibits the best performance in compensating for nonlinear waveform distortion. Additionally, the learning process is effective for the case considering both SPM and XPM compared with the case of SPM only. Finally, we investigate the computational complexity of the LDBP and reveal that the total calculation cost is of the same order as that of a conventional DBP considering only SPM with a 2-step/span configuration.

16.
Opt Lett ; 47(15): 3680-3683, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913288

RESUMO

A wavelength-routing optical switch uses a wavelength-tunable laser at each input port, and this transmitter implements output port selection by tuning the wavelength that is associated with each output port. With coherent transmission, loopback modulation of a local oscillator (LO) carrier generated at the output port can eliminate the need for a wavelength-tunable laser. However, loopback modulation can be unstable since the power fluctuates because fiber traversal by the light creates polarization rotation. Here, we propose a simple polarization-alignment circuit and verify its effectiveness in creating a high-port-count optical switch system. The proposed circuit consists of passive components and aligns the polarization state of the supplied LO carrier to be linearly polarized along the x-direction of a TE-input dual-polarization (DP) IQ modulator. The circuit is shown to yield stable modulation with Q-variation of less than 0.8 dB, regardless of any birefringence along the transmission path. The proposal's effectiveness is verified in optical switch system experiments with DP-QPSK signals; 1,856 × 1,856 switch scale is achieved with loopback modulation.

17.
Cancer Control ; 29: 10732748221140694, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36748438

RESUMO

BACKGROUND: The clinical efficacy of immune checkpoint inhibitors (CPIs) has been proven; however, it is also known that their efficacy as monotherapy is limited, with a response rate of 20% or less in solid tumors. The combination of CPIs and anticancer agents has been actively attempted in solid tumors area. In this systematic review and meta-analysis, we aimed to find favorable combination therapies of programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) inhibitors in terms of anti-tumor efficacy in clinical settings. METHODS: An electronic database search was performed using ClinicalTrials.gov, PubMed, and ASCO/ESMO annual meeting libraries. We included randomized or non-randomized trials designed to evaluate the efficacy and safety of combination therapies of PD-1/PD-L1 inhibitors and other anticancer drug-containing therapies. All clinical studies selected were solid tumors with objective response rate (ORR) data. The quality of the evidence was assessed with the Cochrane risk of bias tool or the Newcastle-Ottawa Scale. Meta-analysis used random effects models to pool results. RESULTS: Sixteen studies involving 3793 patients were included in the primary analysis. These studies have a monotherapy group with PD-1/PD-L1 inhibitors as the control group or the in-study arm/cohort (1863 patients in the combination group with PD-1/PD-L1 inhibitors and 1930 patients in PD-1/PD-L1 inhibitor monotherapy). The pooled results showed that the combination of PD-1/PD-L1 inhibitors and other anticancer drugs significantly improved the ORR (relative risk [RR] = 1.79, 95% confidence interval [CI] 1.46, 2.20). In the subgroup analysis, PD-1/PD-L1 inhibitor plus DNA-synthesis or microtubule inhibitor led to a statistically significant improvement in the ORR compared to PD-1/PD-L1 inhibitor alone. CONCLUSIONS: It was suggested that combinations of PD-1/PD-L1 inhibitors and potential immunogenic cell death (ICD) inducers improve the clinical anti-tumor efficacy, although updated meta-analyses based on the results of ongoing clinical trials are further needed.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Antígeno B7-H1 , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
18.
Circ J ; 87(1): 50-62, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35989303

RESUMO

BACKGROUND: Optimal periprocedural oral anticoagulant (OAC) therapy before catheter ablation (CA) for atrial fibrillation (AF) and the safety profile of OAC discontinuation during the remote period (from 31 days and up to 1 year after CA) have not been well defined.Methods and Results: The RYOUMA registry is a prospective multicenter observational study of Japanese patients who underwent CA for AF in 2017-2018. Of the 3,072 patients, 82.3% received minimally interrupted direct-acting OACs (DOACs) and 10.2% received uninterrupted DOACs. Both uninterrupted and minimally interrupted DOACs were associated with an extremely low thromboembolic event rate. Female, long-standing persistent AF, low creatinine clearance, hepatic disorder, and high intraprocedural heparin dose were independent factors associated with periprocedural major bleeding. At 1 year after CA, DOAC was continued in 55.9% of patients and warfarin in 56.4%. The incidence of thromboembolic and major bleeding events for 1 year was 0.3% and 1.2%, respectively. Age ≥73 years, dementia, and AF recurrence were independently associated with major bleeding events. Univariate analyses revealed that warfarin continuation and off-label overdose of DOACs were risk factors for major bleeding after CA. CONCLUSIONS: High intraprocedural dose of heparin was associated with periprocedural major bleeding events. At 1 year after CA, over half of the patients had continued OAC therapy. Thromboembolic events were extremely low; however, major bleeding occurred in 1.2%. Age ≥73 years, dementia, and AF recurrence were independently associated with major bleeding after CA.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Demência , Tromboembolia , Humanos , Feminino , Idoso , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Varfarina/uso terapêutico , Japão/epidemiologia , Estudos Prospectivos , Resultado do Tratamento , Anticoagulantes/uso terapêutico , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Tromboembolia/epidemiologia , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Heparina/efeitos adversos , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Demência/cirurgia , Administração Oral
19.
Int J Colorectal Dis ; 37(1): 161-170, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34599685

RESUMO

PURPOSE: Colorectal endoscopic submucosal dissection (ESD) produces exfoliated tumor cells that occasionally cause local recurrence. However, the biological characteristics of these tumor cells have not been clarified. The aim of this study was to clarify the genetic background and viability of exfoliated tumor cells in colorectal ESDs, as well as possible method for their elimination. METHODS: Post-ESD intraluminal lavage samples from 19 patients who underwent colorectal ESDs were collected. In four patients with adenocarcinoma, gene mutations in the primary tumors and exfoliated cells in lavage samples were analyzed using a next-generation sequencer (NGS). In 15 patients with adenoma or adenocarcinoma, the viability of exfoliated cells and the cell-killing effect of povidone-iodine on exfoliated cells were evaluated. RESULTS: The analysis using a NGS demonstrated that tumors targeted for ESD had already acquired mutations in many genes involved in cell proliferation, angiogenesis, and invasions. Furthermore, gene mutations between the exfoliated tumor cells and tumors resected by ESDs showed a 92 to 100% concordance. The median viable cell counts and the median viability of exfoliated cells in intraluminal lavage samples after ESDs were 4.9 × 105 cells/mL and 24%, respectively. The viability of the exfoliated cells did not decrease even 12 h after ESD. However, contact with 2.0% povidone-iodine solution reduced both viable cell counts and viability, significantly. CONCLUSION: A large number of tumor cells exfoliated during colorectal ESDs had acquired survival-favorable gene mutations and could survive for some time. Therefore, a lavage using a solution of 2.0% povidone-iodine may be effective against such cells. TRIAL REGISTRATION: The prospective study registered 1317, and the retrospective study registered 2729. The prospective study approved on June 20, 2016, and the retrospective study approved on October 6, 2020.


Assuntos
Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Contagem de Células , Colonoscopia , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Irrigação Terapêutica , Resultado do Tratamento
20.
Hepatol Res ; 52(4): 390-400, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34964539

RESUMO

AIM: Acute-on-chronic liver failure (ACLF) is associated with a high risk of short-term mortality after progression to multiple organ failure. A disintegrin-like and metalloproteinase with thrombospondin type-1 motifs 13 (ADAMTS13) is a metalloproteinase that specifically cleaves multimeric von Willebrand factor (VWF). An imbalance between ADAMTS13 enzyme and VWF substrate is associated with liver cirrhosis progression that induces ACLF. This study examined the relationship between ADAMTS13 and VWF and ACLF development to determine whether ADAMTS13 and VWF are useful predictive biomarkers for ACLF development and prognosis of patients with liver cirrhosis. METHODS: The study enrolled 67 patients with Child-Pugh class A and B liver cirrhosis. ADAMTS13 activity (ADAMTS13:AC) and VWF antigen (VWF:Ag) were measured using enzyme-linked immunosorbent assays. The ratio of VWF:Ag to ADAMTS13:AC (VWF:Ag/ADAMTS13:AC) was used to divide patients into two groups according to the classification and regression tree based on Gray model survival analysis. RESULTS: Compared with patients with Child-Pugh class A liver cirrhosis, class B patients had a higher VWF:Ag/ADAMTS13:AC and a higher risk of ACLF development. Cumulative incidence of ACLF was significantly higher in patients with high (>7.9) versus low (≤7.9) VWF:Ag/ADAMTS13:AC (hazard ratio [HR], 6.50; 95% CI, 2.31-18.29; p < 0.001). Cumulative survival was significantly lower in cirrhotic patients with high versus low VWF:Ag/ADAMTS13:AC (HR 5.11; 95% CI, 1.85-14.14; p = 0.002). CONCLUSIONS: For patients with liver cirrhosis, VWF:Ag/ADAMTS13:AC is associated with functional liver reserve and predicts the development of ACLF and the prognosis.

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