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1.
Phys Rev Lett ; 132(14): 143602, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640396

RESUMEN

We propose and experimentally demonstrate the generation of enhanced optical springs using the optical Kerr effect. A nonlinear optical crystal is inserted into a Fabry-Perot cavity with a movable mirror, and a chain of second-order nonlinear optical effects in the phase-mismatched condition induces the Kerr effect. The optical spring constant is enhanced by a factor of 1.6±0.1 over linear theory. To our knowledge, this is the first realization of optomechanical coupling enhancement using a nonlinear optical effect, which has been theoretically investigated to overcome the performance limitations of linear optomechanical systems. The tunable nonlinearity of demonstrated system has a wide range of potential applications, from observing gravitational waves emitted by binary neutron star postmerger remnants to cooling macroscopic oscillators to their quantum ground state.

2.
Hepatol Res ; 54(6): 503-512, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38642343

RESUMEN

AIM: The diagnosis of drug-induced liver injury (DILI) is challenging. We modified the revised electronic version of the Roussel Uclaf Causality Assessment Method (RUCAM) for the diagnosis of DILI (RECAM), the scoring system developed in US and Spanish cohorts in 2022, and developed RECAM-J 2023 to align with the clinical practice in Japan. In the current study, we introduce RECAM-J 2023 and verify its performance in the context of Japanese patients with DILI. METHODS: After translation of RECAM into Japanese, modifications were made to develop RECAM-J 2023 without any alteration to the scores. To examine the validity and performance of RECAM-J 2023, clinical information on DILI and non-DILI cases in Japan were retrospectively collected. The diagnosis of DILI was made by expert's decision. Then we scored each case using RECAM-J 2023, and calculated area under curve (AUC) values for identification for DILI. RESULTS: We collected data from 538 DILI and 128 non-DILI cases. The sum of highly probable (HP) and probable (PR) cases categorized by RECAM-J 2023 were only 206 (38%) in DILI cases. As the primary cause of low scores was the deduction with missing hepatitis virus markers, which is unlikely to be an issue in prospective applications, we rescored without these deductions. At this time, the sum of HP and PR was raised to 421 (78%). The AUCs of RECAM-J 2023 without deductions were 0.70 and 0.88 for identifying at least HP, and at least PR, respectively. CONCLUSION: RECAM-J 2023, when prospectively used without any missing hepatitis virus markers, provides acceptable performance for identifying at least PR DILI cases in Japanese daily clinical practice.

3.
Mass Spectrom (Tokyo) ; 13(1): A0144, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435076

RESUMEN

The collision-induced dissociation (CID) behaviors of protonated molecules of anabaenopeptins, a group of cyanobacterial cyclic peptides, were investigated in detail using liquid chromatography-tandem mass spectrometry. Although anabaenopeptin A and B share a macrocyclic peptide structure, they give strikingly different fragmentation patterns; the former gives a variety of product ions including cleavages in the cyclic peptide structure, which is useful for structural analysis; whereas the latter gives far fewer product ions and no fragmentation in the cyclic moiety. Energy-resolved CID experiments clarified the mechanism behind the striking difference attributable to the difference in exocyclic amino acid residues, Tyr or Arg. The guanidino group in Arg-containing analogue, anabaenopeptin B, should be by far the most preferred protonation site; the proton would be sequestered at the guanidino group in the protonated molecule, with the lack of proton mobility prohibiting opening of the charge-directed fragmentation channels in the cyclic moiety. Enzymatic hydrolysis of the guanidino group to give citrullinated-anabaenopeptin B restored proton mobility. The fragmentation pattern of the citrullinated peptide became almost identical to that of anabaenopeptin A. The observed fragmentation behaviors of these cyclic peptides were consistent with those of linear peptides, which have been well understood based on the mobile proton model.

4.
Can Urol Assoc J ; 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38319607

RESUMEN

INTRODUCTION: We aimed to clarify the therapeutic outcome of combination therapy using immune-checkpoint inhibitors (ICIs) and/or tyrosine kinase inhibitors (TKIs) for metastatic non-clear-cell renal cell carcinoma (nccRCC). METHODS: We have been retrospectively investigating the therapeutic efficacy and prognosis in 36 patients with metastatic nccRCC undergoing combination therapy using two ICIs, ipilimumab plus nivolumab (ICI-ICI), and ICI plus TKI (ICI-TKI), at Kobe University and affiliated institutions since 2018. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and adverse event (AE) were compared. RESULTS: The first-line regimens was ICI-ICI regimens in 26 cases and ICI-TKI regimens in 10 cases. The ORRs in the ICI-ICI and ICI-TKI groups were 34.6 and 30.0%, respectively (p=0.9433). The 50% PFS for the ICI-TKI group was 9.7 months, significantly longer than that for the ICI-ICI group (4.6 months, p=0.0499), and there was no significant difference in OS between them (p=0.3984). There was no significant difference in the occurrence rate of AE for below grade 2 (p=0.8535) nor above grade 3 (p=0.3786) between the ICI-ICI and ICITKI groups. CONCLUSIONS: From our analysis of real-world data, a better outcome of PFS was expected in the ICI-TKI group compared with that in the ICI-ICI group, while there was no significant difference in OS or ORR.

5.
J Am Heart Assoc ; 12(24): e030356, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38063185

RESUMEN

BACKGROUND: Arterial/aortic tertiary lymphoid organs (ATLOs), characterized by germinal centers, control local arterial immune responses. T follicular helper cells (Tfh), resident in germinal centers, regulate immunoglobulin production and germinal center development. They consist of Tfh1, Tfh2, and Tfh17 subsets. T follicular regulatory (Tfr) cells possess suppressive functions as regulatory T cells and migrate into germinal centers. Immunoglobulin G4 (IgG4)-related diseases manifest in vascular lesions as frequently formed inflammatory aneurysms (IgG4-related abdominal aortic aneurysm [IgG4-AAAs]). IgG4-AAAs contain several ATLOs. METHODS AND RESULTS: We performed whole-slide immunohistochemical image analysis in surgical specimens of IgG4-AAAs (n=21), non-IgG4-related inflammatory AAAs (n=17), atherosclerotic AAAs (n=10), and Takayasu arteritis (n=5). IgG4-AAA was characterized by numerous, large, irregular-shaped ATLOs, and higher numbers of Tfr and Tfh2 cells than Tfh1 cells were present compared with others. The morphologic abnormalities (in number, area, and form) of ATLOs in IgG4-AAAs and the increased number of Tfr cells are closely related to the activity of IgG4-related diseases. All T-cell subsets were more enriched within ATLOs than outside ATLOs. In particular, an increase in Tfr cells in IgG4-AAAs was associated with ATLO formation. Increased Tfh17 cells were found in Takayasu arteritis, and atherosclerotic AAA and non-IgG4-related inflammatory AAAs were characterized by increased Tfh1 cells. CONCLUSIONS: In the classification of vascular lesions, considering the imbalance in T-cell subsets, IgG4-AAA should be positioned as adventitial vasculitis with predominant Tfr and Tfh2 cells, accompanied by the abnormal appearance of ATLOs.


Asunto(s)
Aterosclerosis , Enfermedad Relacionada con Inmunoglobulina G4 , Arteritis de Takayasu , Humanos , Enfermedad Relacionada con Inmunoglobulina G4/patología , Arteritis de Takayasu/patología , Subgrupos de Linfocitos T , Aorta/patología , Inmunoglobulina G , Aterosclerosis/patología , Linfocitos T Colaboradores-Inductores
6.
Oncol Lett ; 26(5): 470, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37809051

RESUMEN

The present study aimed to clarify the relationship between the therapeutic outcome of combination regimens, including immune checkpoint inhibitors (ICIs) and/or tyrosine kinase inhibitors (TKIs), and cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma (mRCC). The present study retrospectively assessed the association between treatment efficacy and prognosis with or without CN, and the timing of CN in 151 patients treated with combination regimens for mRCC who were categorized as intermediate/poor risk. The first-line regimens included the ICI-ICI and ICI-TKI regimens in 98 and 53 cases, respectively. In patients with recurrence after radical surgery (n=66), the 50% PFS times of the ICI-ICI and the ICI-TKI groups were 33.6 months and not reached (NR) (P=0.4032), respectively, and the 50% OS times were 53.7 months and NR (P=0.6886), respectively. Among the 38 patients with metastasis from the initial diagnosis who underwent upfront CN, the 50% PFS times of the ICI-ICI and the ICI-TKI groups were 10.5 and 8.2 months (P=0.5806), respectively, and the 50% OS times were NR and 15.8 months (P=0.0587), respectively. Among the 51 patients who did not receive upfront CN, the 50% PFS time of the ICI-TKI group was significantly higher than that in the ICI-ICI group (4.1 months and NR, respectively; P=0.0210), and the 50% OS times were 29.8 months and NR (P=0.7343), respectively. In conclusion, according to the analysis of real-world data, good therapeutic efficacy can be achieved with any regimen in patients with recurrence after radical surgery. In addition, improved results could be achieved through treatment with ICI-TKI in patients without upfront CN.

7.
Int J Urol ; 30(9): 772-777, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37345413

RESUMEN

OBJECTIVES: The objective of this study was to assess the clinical outcomes following combined treatment with pembrolizumab and axitinib as first-line therapy for patients with advanced RCC. METHODS: This study retrospectively included 47 consecutive Japanese patients who were diagnosed with advanced RCC and subsequently received pembrolizumab and axitinib between February 2020 and January 2022. Efficacy and safety of this combined therapy in these patients were comprehensively investigated. RESULTS: The 47 included patients were classified into the following 3 groups by the IMDC system: favorable, 7 (14.9%); intermediate, 24 (51.1%) and poor, 16 (34.0%). Responses to this combined therapy in the 47 patients were as follows: CR, 8 (17.0%); PR, 20 (42.6%); SD, 16 (34.0%) and PD, 3 (6.4%); thus, the ORR was 59.6%. During the observation period, disease progression and death occurred in 19 (40.4%) and 9 (19.1%) patients, respectively, and the median PFS and OS were 18 months and not reached, respectively. Univariate analyses identified the following significant predictors for poor prognostic outcomes: lack of nephrectomy, liver metastasis, bone metastasis, elevated CRP and IMDC poor risk for PFS; and lack of nephrectomy, non-CCC and elevated CRP for OS. AEs and those corresponding to grade ≥ 3 occurred in all (100%) and 30 (63.8%) patients, respectively. CONCLUSIONS: To our knowledge, this is the first study focusing on real-world outcomes following pembrolizumab and axitinib for treatment-naïve advanced Japanese RCC patients, which showed the efficacy and safety of this combined therapy being similar or even superior to those in clinical trial.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/patología , Axitinib/efectos adversos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Japón , Estudios Retrospectivos
8.
Microorganisms ; 11(3)2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36985150

RESUMEN

Contamination of water by microcystins is a global problem. These potent hepatotoxins demand constant monitoring and control methods in potable water. Promising approaches to reduce contamination risks have focused on natural microcystin biodegradation led by enzymes encoded by the mlrABCD genes. The first enzyme of this system (mlrA) linearizes microcystin structure, reducing toxicity and stability. Heterologous expression of mlrA in different microorganisms may enhance its production and activity, promote additional knowledge on the enzyme, and support feasible applications. In this context, we intended to express the mlrA gene from Sphingosinicella microcystinivorans B9 in an industrial Saccharomyces cerevisiae strain as an innovative biological alternative to degrade microcystins. The mlrA gene was codon-optimized for expression in yeast, and either expressed from a plasmid or through chromosomal integration at the URA3 locus. Recombinant and wild yeasts were cultivated in medium contaminated with microcystins, and the toxin content was analyzed during growth. Whereas no difference in microcystins content was observed in cultivation with the chromosomally integrated strain, the yeast strain hosting the mlrA expression plasmid reduced 83% of toxins within 120 h of cultivation. Our results show microcystinase A expressed by industrial yeast strains as a viable option for practical applications in water treatment.

10.
Int J Urol ; 30(9): 738-745, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36693764

RESUMEN

OBJECTIVES: We clarified the effect of concomitant proton pump inhibitor use on oncological outcomes in patients with advanced urothelial carcinoma treated either with chemotherapy or immune checkpoint inhibitor. METHODS: We retrospectively reviewed patients with advanced urothelial carcinoma who received paclitaxel-gemcitabine therapy or pembrolizumab after platinum-based chemotherapy. The patients were divided into four groups based on the treatment regimen and the concomitant use of proton pump inhibitor. We compared survival outcomes between the groups and determined which factors predicted overall survival. RESULTS: Among the 60 and 75 patients treated with paclitaxel-gemcitabine and pembrolizumab, 15 and 29 used a concomitant proton pump inhibitor. Progression-free and overall survival was significantly shorter in patients who were administered pembrolizumab with concomitant proton pump inhibitor compared to those without. The use of a concomitant proton pump inhibitor had no effect on survival outcomes in patients who received paclitaxel-gemcitabine therapy. Furthermore, progression-free and overall survival were significantly shorter in patients treated with paclitaxel-gemcitabine therapy compared to those treated with pembrolizumab among patients without concomitant proton pump inhibitor. In contrast, there was no difference in survival outcomes between the two regimens among patients with concomitant proton pump inhibitor. Concomitant proton pump inhibitor use was associated with poor overall survival only in patients treated with pembrolizumab. CONCLUSION: The use of a concomitant proton pump inhibitor use had no impact on oncological outcomes in patients with advanced urothelial carcinoma treated with paclitaxel-gemcitabine therapy, different from those treated with pembrolizumab.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Carcinoma de Células Transicionales/patología , Neoplasias de la Vejiga Urinaria/patología , Inhibidores de la Bomba de Protones/uso terapéutico , Paclitaxel/efectos adversos , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
11.
Anticancer Res ; 43(1): 269-274, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36585166

RESUMEN

BACKGROUND/AIM: We aimed to clarify the association between body mass index (BMI) and clinical outcomes of pembrolizumab treatment for advanced urothelial cancer (UC). PATIENTS AND METHODS: We retrospectively reviewed the records of patients with advanced UC who received pembrolizumab after chemotherapy between March 2018 and December 2021. Patients were divided according to BMI into the non-overweight group (BMI <25 kg/m2) and the overweight group (BMI ≥25 kg/m2). We compared the two groups' tumour response, survival rates, and incidence of immune-related adverse events (irAEs) and investigated the factors predicting survival. RESULTS: Of 84 eligible patients, 63 (75%) and 21 (25%) were in the non-overweight and overweight groups, respectively. Although the objective response rate was higher in the overweight group (55%) than that in the non-overweight group (29%), the difference was not significant. Progression-free survival (PFS) was significantly longer in the overweight group (median 15.2 months) than that in the non-overweight group (median 4.8 months; p=0.01). Overall survival was also longer in the overweight group (median 36.1 months) compared to that in the non-overweight group (13.4 months), but the difference was not significant (p=0.11). Multivariable analysis showed that overweight was significantly associated with favourable PFS. Any and severe (grade 3) irAEs were observed in 15 (24%) and 5 (7.9%) patients in the non-overweight group, respectively, and in 8 (38%) and 2 (9.5%) patients in the overweight group, respectively, but the differences were not significant. CONCLUSION: BMI was associated with oncological outcomes in patients with advanced UC who received pembrolizumab but not with the development of irAEs.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/patología , Carcinoma de Células Transicionales/tratamiento farmacológico , Índice de Masa Corporal , Estudios Retrospectivos
12.
Int J Urol ; 30(9): 730-736, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36575640

RESUMEN

OBJECTIVES: The present study comprehensively investigated the significance of several factors reflecting the therapeutic effects of anticancer treatment on overall survival (OS) in advanced urothelial cancer (UC) patients receiving sequential systemic therapy. METHODS: This study included 101 consecutive advanced UC patients who received first-line platinum-based combination chemotherapy followed by second-line pembrolizumab. The impacts of the following factors on OS in these patients were analyzed: responses to chemotherapy, responses to pembrolizumab, progression-free survival (PFS) with chemotherapy, PFS with pembrolizumab, and second PFS (PFS2). RESULTS: The median age of patients was 71 years, and 35 and 66 had UC in the upper urinary tract and bladder, respectively. objective response rate to first-line chemotherapy and second-line pembrolizumab were 37.6% and 19.8%, respectively. Median PFS with chemotherapy, pembrolizumab, and PFS2 were 5, 4, and 9 months, respectively. Uni- and multivariate analyses of the five factors examined identified PFS with pembrolizumab and PFS2 as independent surrogates for OS, with PFS2 (hazard ratio [HR] = 0.23) being more closely associated with OS than PFS with pembrolizumab (HR = 0.31). Furthermore, uni- and multivariate analyses of various prognostic parameters showed the independent impacts of baseline performance status (PS) and neutrophil-to-lymphocyte ratio (NLR) on PFS2. CONCLUSIONS: The present results suggest the potential of PFS2 as an optimal surrogate for OS in advanced UC patients receiving standard sequential systemic therapy and indicate that intensive treatment needs to be considered for those with poor PS and/or high NLR prior to the introduction of first-line chemotherapy.


Asunto(s)
Carcinoma de Células Transicionales , Platino (Metal) , Humanos , Anciano , Supervivencia sin Progresión , Platino (Metal)/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico
13.
Opt Express ; 30(23): 42579-42593, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36366709

RESUMEN

Intracavity squeezing is a promising technique that may improve the sensitivity of gravitational wave detectors and cool optomechanical oscillators to the ground state. However, the photothermal effect may modify the occurrence of optomechanical coupling due to the presence of a nonlinear optical crystal in an optical cavity. We propose a novel method to predict the influence of the photothermal effect by measuring the susceptibility of the optomechanical oscillator and identifying the net optical spring constant and photothermal absorption rate. Using this method, we succeeded in precisely estimating parameters related to even minor photothermal effects, which could not be measured using a previously developed method.

14.
Plant J ; 112(6): 1337-1349, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36288411

RESUMEN

Structure-based high-throughput screening of chemical compounds that target protein-protein interactions (PPIs) is a promising technology for gaining insight into how plant development is regulated, leading to many potential agricultural applications. At present, there are no examples of using high-throughput screening to identify chemicals that target plant transcriptional complexes, some of which are responsible for regulating multiple physiological functions. Florigen, a protein encoded by FLOWERING LOCUS T (FT), was initially identified as a molecule that promotes flowering and has since been shown to regulate flowering and other developmental phenomena such as tuber formation in potato (Solanum tuberosum). FT functions as a component of the florigen activation complex (FAC) with a 14-3-3 scaffold protein and FD, a bZIP transcription factor that activates downstream gene expression. Although 14-3-3 is an important component of FAC, little is known about the function of the 14-3-3 protein itself. Here, we report the results of a high-throughput in vitro fluorescence resonance energy transfer (FRET) screening of chemical libraries that enabled us to identify small molecules capable of inhibiting FAC formation. These molecules abrogate the in vitro interaction between the 14-3-3 protein and the OsFD1 peptide, a rice (Oryza sativa) FD, by directly binding to the 14-3-3 protein. Treatment with S4, a specific hit molecule, strongly inhibited FAC activity and flowering in duckweed, tuber formation in potato, and branching in rice in a dose-dependent manner. Our results demonstrate that the high-throughput screening approach based on the three-dimensional structure of PPIs is suitable in plants. In this study, we have proposed good candidate compounds for future modification to obtain inhibitors of florigen-dependent processes through inhibition of FAC formation.


Asunto(s)
Florigena , Oryza , Florigena/metabolismo , Proteínas de Plantas/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Ensayos Analíticos de Alto Rendimiento , Oryza/metabolismo , Regulación de la Expresión Génica de las Plantas , Flores/genética
15.
Sci Rep ; 12(1): 11596, 2022 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-35804047

RESUMEN

In potato (Solanum tuberosum L.), 14-3-3 protein forms a protein complex with the FLOWERING LOCUS T (FT)-like protein StSP6A and the FD-like protein StFDL1 to activate potato tuber formation. Eleven 14-3-3 isoforms were reported in potato, designated as St14a-k. In this study, the crystal structure of the free form of St14f was determined at 2.5 Å resolution. Three chains were included in the asymmetric unit of the St14f free form crystal, and the structural deviation among the three chain structures was found on the C-terminal helix H and I. The St14f free form structure in solution was also investigated by nuclear magnetic resonance (NMR) residual dipolar coupling analysis, and the chain B in the crystal structure was consistent with NMR data. Compared to other crystal structures, St14f helix I exhibited a different conformation with larger B-factor values. Larger B-factor values on helix I were also found in the 14-3-3 free form structure with higher solvent contents. The mutation in St14f Helix I stabilized the complex with StFDL1. These data clearly showed that the flexibility of helix I of 14-3-3 protein plays an important role in the recognition of target protein.


Asunto(s)
Solanum tuberosum , Proteínas 14-3-3/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tubérculos de la Planta/metabolismo , Solanum tuberosum/genética
16.
Int J Urol ; 29(8): 816-822, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35636920

RESUMEN

Over the last decade, there have been substantial progress in the field of systemic therapy for advanced renal cell carcinoma. Through the transition from treatment with cytokines to molecular-targeted agents, and currently to immuno-oncology drugs, the prognostic outcomes of patients with advanced renal cell carcinoma have been markedly improved. In particular, based on the promising outcomes of recently conducted pivotal randomized clinical trials, immuno-oncology drug-based combination therapy by either dual immune checkpoint inhibition or combined inhibition of an immune checkpoint and tyrosine kinase, is currently regarded as a standard of care for treatment-naïve advanced renal cell carcinoma patients. However, insufficient data are available with respect to the selection of optimal systemic therapies for advanced renal cell carcinoma in the first-line setting due to the lack of a head-to-head comparison between approved immuno-oncology drug-based combination therapies. In this review, therefore, we summarize interesting findings associated with first-line combination therapies for advanced renal cell carcinoma obtained from both randomized clinical trials and real-world clinical practices, in order to present useful guidance to help make treatment decisions for patients with treatment-naïve advanced renal cell carcinoma.


Asunto(s)
Antineoplásicos , Carcinoma de Células Renales , Neoplasias Renales , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/patología , Humanos , Inmunoterapia , Neoplasias Renales/patología , Pronóstico
17.
Yakugaku Zasshi ; 142(1): 39-64, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-34980750

RESUMEN

Lakes Sagami and Tsukui are reservoirs constructed by connecting to the Sagami River. Because of eutrophication of the lakes, cyanobacteria have appeared every year. This review deals with phenomena related to occurrence of cyanobacteria that have been observed for 40 years since 1974 at the lakes. These 40 years of observations raised three interesting issues including the retention of cyanobacteria on their surfaces. These phenomena have been attributed to the usual factors, such as illuminance, nutrition and water temperature, but our research results suggested that they cannot be resolved without the introduction of another factor. We have attempted to elucidate various phenomena involving cyanobacteria in lake ecosystems by chemical ecological methods using volatile organic compounds (VOCs) produced by the cyanobacteria as indicators. One of the VOCs, ß-cyclocitral, was significantly involved in the above phenomena, which was considered to be produced by the carotenoid cleavage dioxygenase (CCD) of the cyanobacteria. ß-Cyclocitral was not produced in the two known CCDs, but two additional CCDs to Microcystis aeruginosa participated to produce the ß-cyclocitral. These CCDs did not directly produce ß-cyclocitral, but it was accumulated in cells as their precursors. The released ß-cyclocitral underwent a Baeyer-Villiger-like oxidation. It was speculated that Microcystis activated the CCD genes through density stress and produced ß-cyclocitral, which acted as an allelopathic substance. As a result, the number of cells of cyanobacteria decreased, and the resulting nitrogen and phosphorus were fed to the living cyanobacteria. It is postulated that this "quorum sensing" was functioning in the above-mentioned issues.


Asunto(s)
Cianobacterias/fisiología , Ecosistema , Agua Dulce/microbiología , Hidrobiología/métodos , Percepción de Quorum , Aldehídos/metabolismo , Cianobacterias/enzimología , Cianobacterias/metabolismo , Dioxigenasas/metabolismo , Diterpenos/metabolismo , Microcystis/metabolismo , Nitrógeno/metabolismo , Oxidación-Reducción , Fósforo/metabolismo , Compuestos Orgánicos Volátiles/metabolismo
18.
Virchows Arch ; 479(6): 1221-1232, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34415430

RESUMEN

Although many germinal centers (GCs) have been reported in immunoglobulin (Ig) G4-related disease, the significance of GCs in IgG4-related disease has not received attention. Both T follicular regulatory cells (Tfr), which are regulatory T cells (Treg) in GCs, and T follicular helper cells (Tfh) produce the cytokine interleukin (IL)-10 and regulate GC development. In whole-slide image analysis in surgical specimens using immunohistochemistry, IgG4-related sclerosing sialadenitis (IgG4-SS, n = 17) was characterized by markedly numerous, large, and irregular-shaped GCs with increased IL-10 + cells and Tfr and Tfh in the total area of the salivary gland compared with controls, including patients with chronic sialadenitis (n = 17) and Sjögren syndrome (n = 15). In particular, the central area of GC in IgG4-SS showed a higher Tfr number and Tfr/Tfh ratio than controls. The number of Tfr in the central area was significantly correlated with the number of IgG4 + plasmacytes and the number, size, and irregularity of GCs. In the mantle area, which surrounds GCs, IgG4-SS showed a higher Treg number and Treg/T helper cells (Th) ratio than controls. In IgG4-SS, the Treg/Th ratio was highest in the mantle area outside GCs and the Tfr/Tfh ratio was highest in the central area inside GCs. However, in controls, the Treg/Th ratio gradually decreased from outside to inside GCs. Our findings reveal that the morphological abnormality of GCs and the characteristic localization and altered balance of Treg and Th in the different compartments of inside and outside GCs would be the novel hallmarks of IgG4-SS.


Asunto(s)
Centro Germinal/inmunología , Enfermedad Relacionada con Inmunoglobulina G4/inmunología , Glándulas Salivales/inmunología , Sialadenitis/inmunología , Células T Auxiliares Foliculares/inmunología , Linfocitos T Reguladores/inmunología , Estructuras Linfoides Terciarias/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Biopsia , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Femenino , Centro Germinal/patología , Humanos , Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico , Inmunohistoquímica , Interleucina-10/análisis , Masculino , Persona de Mediana Edad , Fenotipo , Glándulas Salivales/patología , Sialadenitis/diagnóstico , Células T Auxiliares Foliculares/patología , Linfocitos T Reguladores/patología , Estructuras Linfoides Terciarias/patología
19.
Chemosphere ; 284: 131378, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34217930

RESUMEN

Cyanobacteria produce numerous volatile organic compounds (VOCs) that show a lytic activity against other cyanobacteria. We found the lytic phenomenon under natural conditions and during densification experiments, and also observed the species change of the cyanobacteria during the lysis processes, in which Microcystis finally became dominant. The species change of the cyanobacteria was strongly suggested to depend on the susceptibility of the cyanobacteria toward the VOCs. To verify this suggestion, the susceptibility of the species was evaluated by the minimal inhibitory concentration (MIC) using axenic cyanobacterial strains against ß-cyclocitral, its oxidation products and ß-ionone with the aid of log D. It was found that the difference depended on the susceptibility of the cyanobacteria toward the VOCs, in which ß-cyclocitral played a crucial role and Microcystis had a significantly protective ability compared to the other cyanobacteria. In addition, the species change of cyanobacteria was consistent with the cyanobacterial seasonal succession in Lakes Sagami and Tsukui, based on data that had been accumulated for 10 years. Conventionally, although this phenomenon could be explained by nutrient availability or the physical structure of the environment, the results of this study revealed that it was controlled by the VOCs, particularly ß-cyclocitral produced by the cyanobacteria.


Asunto(s)
Cianobacterias , Microcystis , Compuestos Orgánicos Volátiles , Lagos , Estaciones del Año
20.
Mol Metab ; 49: 101202, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33676029

RESUMEN

OBJECTIVE: Impaired circadian clocks can cause obesity, but their pathophysiological role in brown adipose tissue (BAT), a major tissue regulating energy metabolism, remains unclear. To address this issue, we investigated the effects of complete disruption of the BAT clock on thermogenesis and energy expenditure. METHODS: Mice with brown adipocyte-specific knockout of the core clock gene Bmal1 (BA-Bmal1 KO) were generated and analyzed. RESULTS: The BA-Bmal1 KO mice maintained normal core body temperatures by increasing shivering and locomotor activity despite the elevated expression of thermogenic uncoupling protein 1 in BAT. BA-Bmal1 KO disrupted 24 h rhythmicity of fatty acid utilization in BAT and mildly reduced both BAT thermogenesis and whole-body energy expenditure. The impact of BA-Bmal1 KO on the development of obesity became obvious when the mice were fed a high-fat diet. CONCLUSIONS: These results reveal the importance of the BAT clock for maintaining energy homeostasis and preventing obesity.


Asunto(s)
Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Adipocitos Marrones/metabolismo , Termogénesis/genética , Termogénesis/fisiología , Tejido Adiposo Pardo/metabolismo , Animales , Peso Corporal , Ritmo Circadiano , Frío , Dieta Alta en Grasa , Metabolismo Energético , Ácidos Grasos , Homeostasis , Masculino , Metaboloma , Ratones , Ratones Noqueados , Obesidad/metabolismo , Proteína Desacopladora 1/metabolismo
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