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1.
Ann Hematol ; 103(1): 89-96, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37962621

RESUMO

Thrombopoietin (THPO) is an essential factor for platelet production. Hereditary thrombocythemia (HT) is caused by a germline mutation of THPO, MPL, or JAK2 and is inherited in an autosomal-dominant manner. We identified a Japanese family with HT due to a point mutation of the splicing donor site of the THPO gene (THPO c.13 + 1G > A). Bone marrow biopsy showed increased megakaryocytes mimicking essential thrombocythemia. One affected family member developed chronic myeloid leukemia. We cloned the mutation and developed mutated and wild type THPO expression vectors. Molecular analysis showed that the mutation causes an exon 3 skipping transcript of THPO that abrogates a suppressive untranslated upstream open reading frame. Although the transcript levels of THPO mRNA were comparable, mutated transcripts were more efficiently translated and THPO protein expression was significantly higher than that of the wild type.


Assuntos
Trombocitose , Trombopoetina , Humanos , Japão , Mutação , Trombocitose/genética , Trombopoetina/genética
2.
Bioorg Med Chem ; 97: 117557, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086274

RESUMO

We previously reported that our sugar-conjugated platinum complex (cis-dichloro [(2-fluoro-α-d-glucopylanosidyl) propane-1,3-diamine] platinum: FGC-Pt) has low toxicity and tumor growth inhibitory effect comparable to that of cisplatin. We focused on radioactive Pt isotopes in order to analyze the kinetics of FGC-Pt using gamma-ray imaging techniques, assuming that FGC-Pt could be used for chemotherapy in the future. Therefore, in this study, we aimed to develop a non-invasive method to analyze the biodistribution of FGC-Pt using 191Pt-labeled FGC-Pt ([191Pt]FGC-Pt). 191Pt was produced via the (n,2n) reaction induced by accelerator neutrons. [191Pt]FGC-Pt was prepared using two different methods. In the first method, [191Pt]FGC-Pt (method A) was obtained through the accelerator neutron irradiation of FGC-Pt. In the second method, [191Pt]FGC-Pt (method B) was synthesized using [191Pt]K2PtCl4, which was obtained by the accelerator neutron irradiation of K2PtCl4. Highly purified [191Pt]FGC-Pt was obtained using the latter method, which suggests that the synthetic method using a 191Pt-labeled platinum reagent is suitable for the radioactivation of platinum complexes. We also aimed to investigate whether a significant correlation existed between the biodistribution of FGC-Pt and [191Pt]FGC-Pt in healthy mice 24 h after tail vein administration. FGC-Pt and [191Pt]FGC-Pt were similarly distributed in healthy mice, with a higher accumulation in the liver and kidney 24 h post injection. In addition, a significant correlation (p < 0.05, r = 0.92) between the 191Pt radioactivity concentration (%ID/g (gamma counter)) and platinum concentration (%ID/g (ICP-MS)) was observed in 13 organs. These results suggest that 191Pt-labeled compounds, synthesized using radioactive platinum reagents, can be used to confirm the biodistribution of platinum compounds. Our study on the biodistribution of [191Pt]FGC-Pt is expected to contribute to the development of novel platinum-based drugs in the future.


Assuntos
Antineoplásicos , Neoplasias , Camundongos , Animais , Distribuição Tecidual , Platina , Cisplatino/farmacologia , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Radioisótopos
3.
Biosci Biotechnol Biochem ; 88(6): 648-655, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38490741

RESUMO

Lysophosphatidylcholine (LPC) is present in various foods and contains a choline moiety such as in glycerophosphocholine (GPC). However, the potential of LPC as a choline source remains unclear. This study investigated the single-dose pharmacokinetics of 480 mg soy-derived LPC in 12 healthy men compared with that of either soy oil with the same lipid amount (placebo) or GPC with the same choline amount. Both LPC and GPC supplementation increased plasma choline, serum phospholipid, and serum triglyceride concentrations, but neither of them significantly elevated plasma trimethylamine N-oxide concentration. In addition, although the intake of LPC slightly increased plasma LPC16:0, LPC18:2, and total LPC concentrations, their concentrations remained within physiological ranges. No adverse events were attributed to the LPC supplementation. To the best of our knowledge, this study is the first to compare LPC and GPC pharmacokinetics in humans and shows that LPC can be a source of choline.


Assuntos
Colina , Glicerilfosforilcolina , Glycine max , Lisofosfatidilcolinas , Humanos , Masculino , Lisofosfatidilcolinas/sangue , Glicerilfosforilcolina/farmacocinética , Glicerilfosforilcolina/sangue , Colina/farmacocinética , Colina/sangue , Adulto , Glycine max/química , Suplementos Nutricionais , Adulto Jovem , Triglicerídeos/sangue , Metilaminas/sangue , Metilaminas/farmacocinética
4.
Artigo em Inglês | MEDLINE | ID: mdl-38647077

RESUMO

BACKGROUND: This study aimed to assess anxiety, depression and quality of life (QoL) in patients with head and neck cancer undergoing laryngectomy using comprehensive self-reported questionnaires for a period of up to 5 years. METHODS: This prospective observational study enrolled 150 consecutive patients with locally advanced head and neck cancer who underwent laryngectomy at Nagoya University Hospital between 2007 and 2020. Anxiety, depression and QoL were assessed at baseline (preoperative) and at 3, 6, 12, 24, 36, 48 and 60 months after surgery using two brief self-reported questionnaires, such as the eight-item Short Form Health Survey (SF-8) and the Hospital Anxiety and Depression Scale (HADS). RESULTS: The surgical procedures were total laryngectomy, pharyngo-laryngectomy and pharyngo-laryngo-oesophagectomy in 97 (65%), 41 (27%) and 12 (8%) patients, respectively. All eight items of the SF-8 were significantly worse than those of the normal population at baseline and at 3 months after surgery. However, general health, vitality, mental health and bodily pain improved to normal levels within 1 year after surgery and were maintained for 5 years. In this study, 35% of patients were categorised as potential cases of depression, and 35% were potential cases of anxiety. During the follow-up period, the proportion of patients with anxiety gradually decreased after surgery. Further analysis revealed that the SF-8 and HADS scores and trends in 89 patients without tumour recurrence were similar to those in the total enrolled 150 patients. CONCLUSION: Anxiety, depression and QoL in laryngectomised patients improved at 1 year after surgery and were maintained for up to 5 years. WHAT THIS PAPER ADDS: What is already known on the subject Laryngectomy is associated with prolonged functional and psychological effects and has a major impact on patient quality of life (QoL). Several prospective studies evaluating the QoL in laryngectomised patients have been reported, in which significant deterioration in social functioning was found even 1 year after surgery. What this paper adds to existing knowledge One year is not a sufficient period for laryngectomised patients to return to normal life and spend their time in a social community. A recent review showed that most studies on QoL in laryngectomised patients were conducted under 1 year after the procedure, and there were not enough studies of sufficient quality. This is the first long-term prospective observational study of Japanese patients with head and neck cancer who underwent laryngectomy up to 5 years after surgery. What are the potential or actual clinical implications of this work? Our long-term observational study showed that the scores for anxiety, depression and QoL in laryngectomised patients improved at 1 year after surgery and were maintained for up to 5 years. Clinicians should recognize the importance of psychosocial risk factors in their QoL and multidisciplinary management, including social and psychological support, is essential for long-term laryngectomised survivors.

5.
Br J Haematol ; 201(6): 1144-1152, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37067758

RESUMO

Recent advances in next-generation sequencing (NGS) have enabled the detection of subclinical minute FLT3-ITD. We selected 74 newly diagnosed, cytogenetically normal acute myeloid leukaemia (AML) samples in which FLT3-ITD was not detected by gel electrophoresis. We sequenced them using NGS and found minute FLT3-ITDs in 19 cases. We compared cases with clinically relevant FLT3-ITD (n = 37), cases with minute FLT3-ITD (n = 19) and cases without detectable FLT3-ITD (n = 55). Molecular characteristics (location and length) of minute FLT3-ITD were similar to those of clinically relevant FLT3-ITD. Survival of cases with minute FLT3-ITD was similar to that of cases without detectable FLT3-ITD, whereas the relapse rate within 1 year after onset was significantly higher in cases with minute FLT3-ITD. We followed 18 relapsed samples of cases with clinically FLT3-ITD-negative at diagnosis. Two of 3 cases with minute FLT3-ITD relapsed with progression to clinically relevant FLT3-ITD. Two of 15 cases in which FLT3-ITD was not detected by NGS relapsed with the emergence of minute FLT3-ITD, and one of them showed progression to clinically relevant FLT3-ITD at the second relapse. We revealed the clonal dynamics of subclinical minute FLT3-ITD in clinically FLT3-ITD-negative AML. Minute FLT3-ITD at the initial AML can expand to become a dominant clone at relapse.


Assuntos
Leucemia Mieloide Aguda , Recidiva Local de Neoplasia , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Tirosina Quinase 3 Semelhante a fms/genética , Mutação , Prognóstico
6.
Bioconjug Chem ; 34(11): 2055-2065, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37883660

RESUMO

Immunogenic responses by protein therapeutics often lead to reduced therapeutic effects and/or adverse effects via the generation of neutralizing antibodies and/or antidrug antibodies (ADA). Mirror-image proteins of the variable domain of the heavy chain of the heavy chain antibody (VHH) are potential novel protein therapeutics with high-affinity binding to target proteins and reduced immunogenicity because these mirror-image VHHs (d-VHHs) are less susceptible to proteolytic degradation in antigen-presenting cells (APCs). In this study, we investigated the preparation protocols of d-VHHs and their biological properties, including stereoselective target binding and immunogenicity. Initially, we established a facile synthetic process of two model VHHs [anti-GFP VHH and PMP12A2h1 (monomeric VHH of caplacizumab)] and their mirror-image proteins by three-step native chemical ligations (NCLs) from four peptide segments. The folded synthetic VHHs (l-anti-GFP VHH and l-PMP12A2h1) bound to the target proteins (EGFP and vWF-A1 domain, respectively), while their mirror-image proteins (d-anti-GFP VHH and d-PMP12A2h1) showed no binding to the native proteins. For biodistribution studies, l-VHH and d-VHH with single radioactive indium diethylenetriamine-pentaacid (111In-DTPA) labeling at the C-terminus were designed and synthesized by the established protocol. The distribution profiles were essentially similar between l-VHH and d-VHH, in which the probes accumulated in the kidney within 15 min after intravenous administration in mice, because of the small molecular size of VHHs. Comparative assessment of the immunogenicity responses revealed that d-VHH-induced levels of ADA generation were significantly lower than those of native VHH, regardless of the peptide sequences and administration routes. The resulting scaffold investigated should be applicable in the design of d-VHHs with various C-terminal CDR3 sequences, which can be identified by screening using display technologies.


Assuntos
Camelídeos Americanos , Anticorpos de Domínio Único , Camundongos , Animais , Preparações Farmacêuticas , Distribuição Tecidual , Cadeias Pesadas de Imunoglobulinas , Anticorpos Neutralizantes , Camelídeos Americanos/metabolismo
7.
Ann Hematol ; 102(11): 3103-3113, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37597110

RESUMO

IKZF1 deletion is a recurrent genomic alteration in B-cell acute lymphoblastic leukemia (B-ALL) and is divided into dominant-negative (DN) and loss of function (LOF) deletions. The prognostic impact of each deletion has not been fully elucidated. We retrospectively analyzed 117 patients with adult B-ALL including 60 patients with BCR::ABL1-positive B-ALL and 57 patients with BCR::ABL1-negative B-ALL by the fluorescence in situ hybridization (FISH) method for IKZF1 deletion and multiplex PCR for the 4 most common IKZF1 deletions (∆4-7, ∆2-7, ∆2-8, and ∆4-8). Samples, in which IKZF1 deletion was detected by FISH but a specific type of deletion was not identified by the PCR, were categorized as "other." Patients were classified into a DN group that had at least 1 allele of ∆4-7 (n = 23), LOF and other group (n = 40), and wildtype group (n = 54). DN type IKZF1 deletions were found in 33.3% of BCR::ABL1-positive cases and 5.2% of BCR::ABL1-negative cases. LOF and other type IKZF1 deletions were found in 43.4% of BCR::ABL1-positive cases and 24.6% of BCR::ABL1-negative cases. Patients with the DN group showed significantly higher overall survival (OS) than that of the LOF and other and WT groups (P = 0.011). Multivariate analysis including age, WBC counts, complex karyotype, and DN type IKZF1 deletion showed that the DN type of IKZF1 deletion (HR = 0.22, P = 0.013) had a positive impact and age ≥ 65 (HR = 1.92, P = 0.029) had a negative impact on OS. The prognostic impact of IKZF1 deletion depends on the type of deletion and DN type of IKZF1 deletion showed better prognosis in adult B-ALL patients.Clinical trial registration This study was part of a prospective observational study (Hokkaido Leukemia Net, UMIN000048611). It was conducted in compliance with ethical principles based on the Helsinki Declaration and was approved by the institutional review board of Hokkaido University Hospital (#015-0344).

8.
Eur J Haematol ; 111(4): 620-627, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37465857

RESUMO

OBJECTIVES: The cryptic fusion oncogene NUP98::NSD1 is known to be associated with FLT3-ITD mutation in acute myeloid leukemia (AML), and an independent poor prognostic factor in pediatric AML. However, there are little data regarding the clinical significance of NUP98::NSD1 in adult cohort. METHODS: We conducted a multicenter retrospective study to investigate the prevalence, clinical characteristics, and prognostic impact of NUP98::NSD1 in adult FLT3-ITD-positive AML patients. RESULTS: In a total of 97 FLT3-ITD-positive AML patients, six cases (6.2%) were found to harbor the NUP98::NSD1 fusion transcript. NUP98::NSD1 positive cases had significantly higher platelet counts and a higher frequency of FAB-M4 morphology than NUP98::NSD1 negative cases. NUP98::NSD1 was found to be mutually exclusive with NPM1 mutation, and was accompanied by the WT1 mutation in three of the six cases. The presence of NUP98::NSD1 fusion at the time of diagnosis predicted poor response to cytarabine-anthracycline-based intensive induction chemotherapy (induction failure rate: 83% vs. 36%, p = .038). Five of the six cases with NUP98::NSD1 underwent allogeneic hematopoietic stem cell transplantation (HSCT). Two of the five cases have successfully maintained remission, with one of them being rescued through a second HSCT. CONCLUSIONS: Detecting NUP98::NSD1 in adult FLT3-ITD-positive AML is crucial to recognizing chemotherapy-resistant group.


Assuntos
Leucemia Mieloide Aguda , Criança , Humanos , Adulto , Estudos Retrospectivos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Prognóstico , Mutação , Tirosina Quinase 3 Semelhante a fms/genética , Histona-Lisina N-Metiltransferase/genética
9.
BMC Gastroenterol ; 23(1): 106, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37020184

RESUMO

OBJECTIVE: Comorbid psychiatric disorders negatively affect the survival rate of patients with some physical disorders. In liver transplant recipients, various psychiatric disorders have been identified as worsening prognosis. However, little is known about how the presence of any comorbid (overall) disorders affect the survival rate of transplant recipients. In this study, we examined the effect of overall comorbid psychiatric disorders on survival rate in liver transplant recipients. METHODS: A total of 1006 recipients who underwent liver transplantation between September 1997 and July 2017 across eight transplant facilities with a psychiatric consultation-liaison team were identified consecutively. Recipients were categorized into those with comorbid psychiatric disorders and those without comorbid psychiatric disorders. In the comorbid psychiatric disorder group, psychiatric disorder diagnosis and time of diagnosis were investigated retrospectively. RESULTS: Of the 1006 recipients, 294 (29.2%) had comorbid psychiatric disorders. Comorbid psychiatric disorders in the 1006 recipients were insomnia (N = 107, 10.6%), delirium (N = 103, 10.2%), major depressive disorder (N = 41, 4.1%), adjustment disorder (N = 19, 1.9%), anxiety disorder (N = 17, 1.7%), intellectual disability (N = 11, 1.1%), autism spectrum disorder (N = 7, 0.7%), somatic symptom disorder (N = 4, 0.4%) schizophrenia (N = 4, 0.4%), substance use disorder (N = 24, 2.4%) and personality disorder (N = 2, 0.2%). The most common time of psychiatric disorder diagnosis was within the first 3 months after liver transplantation (51.6%). The final mortality in patients with comorbid psychiatric disorder diagnosis during the five periods (pretransplant, transplant to 3 months, months to 1 year, 1 to 3 years, and over 3 years posttransplant) was 16.2%, 18.8%, 39.1%, 28.6%, and 16.2% respectively, and there were no significant differences between the five periods (χ2 = 8.05, df = 4, p = 0.09). Overall comorbid psychiatric disorders were significantly associated with shorter survival time (log-rank test: p = 0.01, hazard ratio: 1.59 [95% confidence interval: 1.14-2.21], survival rate at the endpoint [%]: 62.0 vs. 83.3). However, after adjusting for confounding variables using Cox proportional hazards regression, there was no significant effect of overall comorbid psychiatric disorders on prognosis. CONCLUSION: Comorbid psychiatric disorders did not affect the survival rate of liver transplant recipients in this study.


Assuntos
Transtorno do Espectro Autista , Transtorno Depressivo Maior , Transplante de Fígado , Transtornos Mentais , Humanos , Estudos Retrospectivos , Encaminhamento e Consulta
10.
Biol Pharm Bull ; 46(2): 320-333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36724960

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by dementia. The most characteristic pathological changes in AD brain include extracellular amyloid-ß (Aß) accumulation and neuronal loss. Particularly, cholinergic neurons in the nucleus basalis of Meynert are some of the first neuronal groups to degenerate; accumulating evidence suggests that Aß oligomers are the primary form of neurotoxicity. Bacopa monniera is a traditional Indian memory enhancer whose extract has shown neuroprotective and Aß-reducing effects. In this study, we explored the low molecular weight compounds from B. monniera extracts with an affinity to Aß aggregates, including its oligomers, using Aß oligomer-conjugated beads and identified plantainoside B. Plantainoside B exhibited evident neuroprotective effects by preventing Aß attachment on the cell surface of human induced pluripotent stem cell (hiPSC)-derived cholinergic neurons. Moreover, it attenuated memory impairment in mice that received intrahippocampal Aß injections. Furthermore, radioisotope experiments revealed that plantainoside B has affinity to Aß aggregates including its oligomers and brain tissue from a mouse model of Aß pathology. In addition, plantainoside B could delay the Aß aggregation rate. Accordingly, plantainoside B may exert neuroprotective effects by binding to Aß oligomers, thus interrupting the binding of Aß oligomers to the cell surface. This suggests its potential application as a theranostics in AD, simultaneously diagnostic and therapeutic drugs.


Assuntos
Doença de Alzheimer , Bacopa , Células-Tronco Pluripotentes Induzidas , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Camundongos , Humanos , Animais , Bacopa/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Células-Tronco Pluripotentes Induzidas/metabolismo , Peptídeos beta-Amiloides/toxicidade , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/tratamento farmacológico , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico
11.
Nucleic Acids Res ; 49(19): 10807-10817, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-33997906

RESUMO

In ribosomal translation, the accommodation of aminoacyl-tRNAs into the ribosome is mediated by elongation factor thermo unstable (EF-Tu). The structures of proteinogenic aminoacyl-tRNAs (pAA-tRNAs) are fine-tuned to have uniform binding affinities to EF-Tu in order that all proteinogenic amino acids can be incorporated into the nascent peptide chain with similar efficiencies. Although genetic code reprogramming has enabled the incorporation of non-proteinogenic amino acids (npAAs) into the nascent peptide chain, the incorporation of some npAAs, such as N-methyl-amino acids (MeAAs), is less efficient, especially when MeAAs frequently and/or consecutively appear in a peptide sequence. Such poor incorporation efficiencies can be attributed to inadequate affinities of MeAA-tRNAs to EF-Tu. Taking advantage of flexizymes, here we have experimentally verified that the affinities of MeAA-tRNAs to EF-Tu are indeed weaker than those of pAA-tRNAs. Since the T-stem of tRNA plays a major role in interacting with EF-Tu, we have engineered the T-stem sequence to tune the affinity of MeAA-tRNAs to EF-Tu. The uniform affinity-tuning of the individual pairs has successfully enhanced the incorporation of MeAAs, achieving the incorporation of nine distinct MeAAs into both linear and thioether-macrocyclic peptide scaffolds.


Assuntos
Aminoácidos/genética , Escherichia coli/genética , Fator Tu de Elongação de Peptídeos/química , Biossíntese de Proteínas , Aminoacil-RNA de Transferência/química , Thermus/genética , Aminoácidos/metabolismo , Pareamento de Bases , Sequência de Bases , Sítios de Ligação , Escherichia coli/metabolismo , Engenharia Genética/métodos , Cinética , Metilação , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Oligonucleotídeos/genética , Oligonucleotídeos/metabolismo , Fator Tu de Elongação de Peptídeos/genética , Fator Tu de Elongação de Peptídeos/metabolismo , Peptidomiméticos/química , Peptidomiméticos/metabolismo , Ligação Proteica , Aminoacil-RNA de Transferência/genética , Aminoacil-RNA de Transferência/metabolismo , Termodinâmica , Thermus/metabolismo
12.
Gan To Kagaku Ryoho ; 50(6): 713-717, 2023 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-37317606

RESUMO

Bevacizumab(BV)combination chemotherapy in colorectal cancer under subcutaneously implanted central venous port (CVP)implantation may cause complications after the implantation. Measurement of D-dimer is recommended to predict thromboembolism and other complications, but its relevance to complications after CVP implantation remains unclear. In this study, we investigated the association between D-dimer and complications after CVP implantation in 93 patients with colorectal cancer who received BV combination chemotherapy. Complications after CVP implantation occurred in 26 patients (28%), and those with VTE showed higher D-dimer values at the onset of the complication. The D-dimer values of the patients with VTE displayed a sharp increase at the onset of the disease, while those with an abnormal CVP implantation site showed a more variable course. Measurement of D-dimer levels appeared useful in estimating the incidence of VTE and abnormal CVP implantation sites in post-CVP implantation complications of BV combination chemotherapy for colorectal cancer. Further, monitoring not only the quantitative values but also the fluctuations over time is also important.


Assuntos
Neoplasias Colorretais , Tromboembolia Venosa , Humanos , Bevacizumab/efeitos adversos , Quimioterapia Combinada , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia
13.
J Am Chem Soc ; 144(3): 1082-1086, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-34918921

RESUMO

In one-dimensional systems with partially filled valence bands, simultaneous changes occur in the electronic states and crystal structures. This is known as the Peierls transition. The Peierls transition (cation dimerization) in VO2, which has a quasi-one-dimensional structure, is well-known, and its mechanism has been extensively discussed. Honeycomb lattices exhibit the Peierls instability owing to their low dimensionality. However, cation dimerization is rare in the 3d1 honeycomb lattice system. Here, we perform an in-depth examination of the V-V dimerization (formation of V-V direct bond) in ilmenite-type MgVO3, which is a 3d1 honeycomb lattice system. A ladderlike pattern was observed in the V-V dimers through synchrotron X-ray experiments at temperatures below 500 K. This dimerization was accompanied by a magnetic-to-nonmagnetic transition. Moreover, a valence bond liquid phase may exist at 500-600 K. Our results reveal the behavior of the valence electrons in the 3d1 honeycomb lattice system.

14.
J Synchrotron Radiat ; 29(Pt 6): 1414-1419, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36345749

RESUMO

A picosecond pump-probe resonant soft X-ray scattering measurement system has been developed at the Photon Factory storage ring for highly efficient data collection. A high-repetition-rate high-power compact laser system has been installed to improve efficiency via flexible data acquisition to a sub-MHz frequency in time-resolved experiments. Data are acquired by gating the signal of a channel electron multiplier with a pulse-counting mode capable of discriminating single-bunch soft X-ray pulses in the dark gap of the hybrid operation mode in the storage ring. The photoinduced dynamics of magnetic order for multiferroic manganite SmMn2O5 are clearly demonstrated by the detection of transient changes in the resonant soft X-ray scattering intensity around the Mn LIII- and O K-edges.

15.
Int Immunol ; 33(4): 225-240, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33165593

RESUMO

MDA5 is a cytoplasmic sensor of viral RNA, triggering type I interferon (IFN-I) production. Constitutively active MDA5 has been linked to autoimmune diseases such as systemic lupus erythematosus, Singleton-Merten syndrome (SMS) and Aicardi-Goutières syndrome (AGS), a genetically determined inflammatory encephalopathy. However, AGS research is challenging due to the lack of animal models. We previously reported lupus-like nephritis and SMS-like bone abnormalities in adult mice with constitutively active MDA5 (Ifih1G821S/+), and herein demonstrate that these mice also exhibit high lethality and spontaneous encephalitis with high IFN-I production during the early postnatal period. Increases in the number of microglia were observed in MDA5/MAVS signaling- and IFN-I-dependent manners. Furthermore, microglia showed an activated state with an increased phagocytic capability and reduced expression of neurotrophic factors. Although multiple auto-antibodies including lupus-related ones were detected in the sera of the mice as well as AGS patients, Ifih1G821S/+Rag2-/- mice also exhibited up-regulation of IFN-I, astrogliosis and microgliosis, indicating that auto-antibodies or lymphocytes are not required for the development of the encephalitis. The IFN-I signature without lymphocytic infiltration observed in Ifih1G821S/+ mice is a typical feature of AGS. Collectively, our results suggest that the Ifih1G821S/+ mice are a model recapitulating AGS and that microglia are a potential target for AGS therapy.


Assuntos
Doenças Autoimunes do Sistema Nervoso/genética , Doenças Autoimunes do Sistema Nervoso/patologia , Encefalite/genética , Interferon Tipo I/imunologia , Helicase IFIH1 Induzida por Interferon/metabolismo , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/patologia , Animais , Autoanticorpos/sangue , Modelos Animais de Doenças , Encefalite/patologia , Helicase IFIH1 Induzida por Interferon/genética , Linfócitos/imunologia , Camundongos , Camundongos Knockout , Microglia/metabolismo
16.
Photochem Photobiol Sci ; 21(4): 437-446, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35394642

RESUMO

Phycocyanobilin, the primary pigment of both light perception and light-harvesting in cyanobacteria, is synthesized from biliverdin IXα (BV) through intermediate 181, 182-dihydrobiliverdin (181, 182-DHBV) by a phycocyanobilin:ferredoxin oxidoreductase (PcyA). In our previous study, we discovered two PcyA homologs (AmPcyAc and AmPcyAp) derived from Acaryochloris marina MBIC 11017 (A. marina) that exceptionally uses chlorophyll d as the primary photosynthetic pigment, absorbing longer wavelength far-red light than chlorophyll a, the photosynthetic pigment found in most cyanobacteria. Biochemical characterization of the two PcyA homologs identified functional diversification of these two enzymes: AmPcyAc provides 181, 182-DHBV, and PCB to the cyanobacteriochrome (CBCR) photoreceptors, whereas, AmPcyAp specifically provides PCB to the light-harvesting phycobilisome subunit. In this study, we focused on the residues necessary for 181, 182-DHBV supply to the CBCR photoreceptors by AmPcyAc. Based on the SyPcyA structure, we concentrated on the 30 residues that constitute the substrate-binding pocket. Among them, we discovered that Leu151 and Val225 in AmPcyAc were both substituted with isoleucine. During the enzymatic reaction, the SyPcyA variant molecule, possessing V225I and L151I replacements, accumulates the 181, 182-DHBV and supplies it to a CBCR molecule derived from A. marina. It is worth noting that the substitution of Val225 with isoleucine was specifically conserved among the Acaryochloris genus. Collectively, we propose that the specific evolution of PcyA among the Acaryochloris genus may correlate with the acquisition of Chl. d synthetic ability and growth in long-wavelength far-red light environments.


Assuntos
Isoleucina , Oxirredutases , Clorofila , Clorofila A , Ficobilinas/química , Ficocianina
17.
Inorg Chem ; 61(20): 7841-7846, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35532118

RESUMO

The nature of chemical bonds determines the electronic and magnetic properties of compounds. A metal-metal bonding (V-V dimer) and its effect on the magnetism of ilmenite-type CoVO3 were studied. Polycrystalline CoVO3 samples were synthesized using a high-pressure synthesis method. Crystal structure refinement revealed that V-V dimers exist at temperatures below 550 K in the vanadium layers. Co2+ in CoVO3 exhibits an S = 3/2 state, whereas a Jeff = 1/2 state was reported in ilmenite-type CoTiO3. The existence of V-V dimers reduces the structural symmetry (from R3 to P1), which can change the magnetic ground state.

18.
Bioorg Med Chem ; 69: 116915, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35802951

RESUMO

Prostate-specific membrane antigen (PSMA), expressed in prostate cancer cells, is being investigated extensively worldwide as a target for imaging and therapy of prostate cancer. Various radioiodinated PSMA imaging probes have been developed, and their structure has a peptidomimetic urea-based skeleton as a pharmacophore. For direct radioiodination of molecules containing these peptidomimetic structures, prior studies performed radioiododestannylation or electrophilic radioiodination of tyrosine residues. However, although these radiolabeling methods are frequently used, there are some issues with precursor toxicity and by-product production. Therefore, it is required to investigate a radiolabeling method that can be used for the radiosynthesis of radioiodinated PSMA imaging probes with urea-based peptidomimetic structures. We recently reported that copper-mediated radioiodination via a boronic precursor is an effective method for directly labeling a peptide. This radiohalogenation method was expected to be an effective method for radiosynthesis of PSMA imaging probes with a peptidomimetic structure. In this study, to confirm that this labeling method applies to the synthesis of the PSMA imaging probe, we synthesized PSMA imaging probes labeled with 125I and 77Br ([125I]mIB-PS and [77Br]mBrB-PS) using a copper-mediated radiohalogenation via common boronic precursors and investigated optimal boronic precursor and labeling conditions. As a result, the radiochemical yields of [125I]mIB-PS and [77Br]mBrB-PS were improved to > 93% at room temperature by optimizing the structure of the boronic precursor. We demonstrate that copper-mediated nucleophilic radiochemistry using a boronic precursor is a promising radiosynthetic method of PSMA imaging probes. Although we focused on the synthesis of PSMA imaging probes, the results in this study will also be useful for the synthesis of various radioiodine or radiobromine-labeled bioactive molecules.


Assuntos
Peptidomiméticos , Neoplasias da Próstata , Antígenos de Superfície , Boro , Linhagem Celular Tumoral , Cobre , Glutamato Carboxipeptidase II , Humanos , Radioisótopos do Iodo , Masculino , Tomografia por Emissão de Pósitrons , Próstata , Neoplasias da Próstata/diagnóstico por imagem , Compostos Radiofarmacêuticos , Ureia
19.
Digestion ; 103(5): 386-396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35863326

RESUMO

INTRODUCTION: Studies have reported the feasibility of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) in elderly people with respect to both short- and long-term outcomes. As the elderly population in society increases, the requirement for managing super-elderly patients aged ≥85 years with EGC will also increase. This study aims to identify the long-term clinical outcomes of ESD for clinical T1N0 EGC in patients aged ≥85 years. METHODS: A total of 370 consecutive patients aged ≥85 years with clinical T1N0 EGC who were managed in 11 institutions were reviewed retrospectively. On the basis of treatment strategy, we compared the overall survival (OS) and disease-specific survival (DSS) after performing propensity score-matched analysis between patients undergoing ESD (ESD group) and those not undergoing treatment (conservative treatment group). The potential prognostic factors were also investigated in the propensity score-matched patients. RESULTS: After propensity score matching, we found that the 3-year OS and DSS rates were significantly higher in the ESD group than in the conservative treatment group (OS, 82.2% vs. 50.5%; p < 0.001; DSS, 100% vs. 80.1%; p = 0.008). Furthermore, ESD was identified as a significant factor for prolonged OS, whereas Charlson comorbidity index (CCI) ≥3 and prognostic nutritional index (PNI) <36.2 were associated with reduced OS. CONCLUSION: ESD was associated with improved OS in patients with clinical T1N0 EGC aged ≥85 years compared with the absence of treatment. Furthermore, CCI and PNI were helpful for patient selection.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Idoso , Idoso de 80 Anos ou mais , Tratamento Conservador , Ressecção Endoscópica de Mucosa/métodos , Mucosa Gástrica/cirurgia , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Resultado do Tratamento
20.
Surg Endosc ; 36(4): 2279-2289, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33860352

RESUMO

BACKGROUND: Long-term outcomes of endoscopic submucosal dissection (ESD) for esophageal squamous cell carcinoma (ESCC) have not been assessed in a large, multicenter cohort. We aimed to evaluate long-term outcomes of ESD for ESCC in a real-world setting. METHODS: We retrospectively recruited 659 patients who underwent ESD for ESCC at ten institutions from January 2007 to December 2015. Of these, 566 patients were analyzed and classified into three groups according to the pathologic invasion depth after ESD: epithelium/lamina propria mucosa (EP/LPM group: 454 patients), muscularis mucosa/submucosa invasion ≤ 200 µm below the inferior margin of the muscularis mucosa (MM/SM1 group: 81 patients), and submucosa invasion > 200 µm below the MM inferior margin (SM2 group: 31 patients). RESULTS: The 5-year overall survival rates in the EP/LPM, MM/SM1, and SM2 groups were 92.6%, 80.0%, and 62.7%, respectively, while the 5-year disease-specific survival rates were 99.7%, 96.9%, and 88.3%, respectively. Multivariate analyses revealed that the invasion depth, Charlson Comorbidity Index (CCI), and prognostic nutritional index (PNI) were independent prognostic factors. Hazard ratios in the MM/SM1 and SM2 groups were 2.25 (95% confidence interval [CI] 1.04-4.83; P = 0.038) and 3.18 (95% CI 1.08-9.34; P = 0.036), respectively, compared to those in the EP/LPM group, while those for patients with a CCI ≥ 3 and PNI ≤ 47.75 were 3.25 (95% CI 1.79-5.89; P < 0.001) and 2.42 (95% CI 1.26-4.65; P = 0.008), respectively. CONCLUSIONS: This study identified that invasion depth, presence of comorbid diseases and preoperative nutritional status are independent prognostic risk factors associated with ESCC patients undergoing ESD.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Estudos de Coortes , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/cirurgia , Humanos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
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