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1.
Nutr Cancer ; : 1-14, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33754895

RESUMO

Limited information is available regarding the impact of body weight loss (BWL) in patients with advanced gastric cancer (AGC) who receive second-line chemotherapy. We retrospectively reviewed data for consecutive AGC patients who received second-line treatment with taxane-based chemotherapy at our institution between January 2014 and September 2018. We calculated variables, including percent BWL per month during chemotherapy (%BWL/m), and analyzed the correlations between BWL and other clinicopathological parameters with survival. Forty-four AGC patients were registered (median age, 67.5 years; females, n = 16 [36.3%]; severe ascites, n = 12 [27.3%]). The median overall survival was significantly shorter among patients with a %BWL/m of 1% or more, compared with patients with less weight loss (6.3 mo, vs. 12.3 mo, P = 0.038). The %BWL/m (≥1% vs. <1%) was significantly correlated with survival in a univariate analysis (HR = 2.11, P = 0.04), and the survival period was shorter for patients with severe ascites (HR = 1.92; 95% CI, 0.90-3.90) and if their %BWL/m was 1% or more (HR = 2.01; 95% CI, 0.98-4.10) in a multivariate analysis. In conclusion, BWL during second-line chemotherapy was associated with a poor prognosis among patients with AGC.

2.
EMBO J ; 40(4): e105375, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33470442

RESUMO

Thalidomide causes teratogenic effects by inducing protein degradation via cereblon (CRBN)-containing ubiquitin ligase and modification of its substrate specificity. Human P450 cytochromes convert thalidomide into two monohydroxylated metabolites that are considered to contribute to thalidomide effects, through mechanisms that remain unclear. Here, we report that promyelocytic leukaemia zinc finger (PLZF)/ZBTB16 is a CRBN target protein whose degradation is involved in thalidomide- and 5-hydroxythalidomide-induced teratogenicity. Using a human transcription factor protein array produced in a wheat cell-free protein synthesis system, PLZF was identified as a thalidomide-dependent CRBN substrate. PLZF is degraded by the ubiquitin ligase CRL4CRBN in complex with thalidomide, its derivatives or 5-hydroxythalidomide in a manner dependent on the conserved first and third zinc finger domains of PLZF. Surprisingly, thalidomide and 5-hydroxythalidomide confer distinctly different substrate specificities to mouse and chicken CRBN, and both compounds cause teratogenic phenotypes in chicken embryos. Consistently, knockdown of Plzf induces short bone formation in chicken limbs. Most importantly, degradation of PLZF protein, but not of the known thalidomide-dependent CRBN substrate SALL4, was induced by thalidomide or 5-hydroxythalidomide treatment in chicken embryos. Furthermore, PLZF overexpression partially rescued the thalidomide-induced phenotypes. Our findings implicate PLZF as an important thalidomide-induced CRBN neosubstrate involved in thalidomide teratogenicity.

3.
World J Gastrointest Oncol ; 12(11): 1364-1371, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-33250967

RESUMO

BACKGROUND: Fistula formation is a severe adverse event related to antiangiogenetic agents such as bevacizumab and inferior mesenteric arteriovenous fistula (IMAVF) is a result of acquired factor, especially colon surgery. However, IMAVF occurs very rarely and there are few reports in patients during chemotherapy. We report a case of a patient who developed IMAVF during treatment with bevacizumab in metastatic colorectal cancer (mCRC) after colon surgery. CASE SUMMARY: An 81-year-old man was diagnosed with descending colon cancer and underwent left hemicolectomy without any complications. He was definitely diagnosed with high-risk stage 2 and received tegafur-uracil plus leucovorin as adjuvant chemotherapy. Three years and 6 mo after the operation, the cancer relapsed with peritoneal dissemination. The patient underwent CyberKnife radiosurgery targeting the recurrent tumor and received chemotherapy with S-1 plus bevacizumab. At 1 year after chemotherapy, he complained of severe diarrhea, which is suspected drug-induced colitis. As diarrhea worsened despite the termination of treatment, he underwent colonoscopy and computed tomography (CT) scans that revealed edematous change from sigmoid to rectosigmoid colon. CT scans also revealed an aneurysm adjacent to the inferior mesenteric vein and multidetector CT angiography showed the IMAVF. Elective angiography confirmed the diagnosis of an IMAVF and it was successfully treated by arterial embolization. The patient resumed chemotherapy with only S-1 6 mo after embolization. CONCLUSION: Clinicians should keep in mind the probability of severe diarrhea arose from IMAVF in mCRC patients treated with bevacizumab.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33200538

RESUMO

BACKGROUND: Hepatectomy is standard treatment for colorectal liver metastases; however, it is unclear whether liver metastases from other primary cancers should be resected or not. The Japanese Society of Hepato-Biliary-Pancreatic Surgery therefore created clinical practice guidelines for the management of metastatic liver tumors. METHODS: Eight primary diseases were selected based on the number of hepatectomies performed for each malignancy per year. Clinical questions were structured in the population, intervention, comparison, and outcomes (PICO) format. Systematic reviews were performed, and the strength of recommendations and the level of quality of evidence for each clinical question were discussed and determined. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations. RESULTS: The eight primary sites were grouped into 5 categories based on suggested indications for hepatectomy and consensus of the guidelines committee. Fourteen clinical questions were devised, covering 5 topics: (1) diagnosis, (2) operative treatment, (3) ablation therapy, (4) the eight primary diseases, and (5) systemic therapies. The grade of recommendation was strong for 1 clinical question and weak for the other 13 clinical questions. The quality of the evidence was moderate for 2 questions, low for 10, and very low for 2. A flowchart was made to summarize the outcomes of the guidelines for the indications of hepatectomy and systemic therapy. CONCLUSIONS: These guidelines were developed to provide useful information based on evidence in the published literature for the clinical management of liver metastases, and they could be helpful for conducting future clinical trials to provide higher-quality evidence.

5.
Nat Commun ; 11(1): 5972, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33235224

RESUMO

Genome-wide DNA demethylation is a unique feature of mammalian development and naïve pluripotent stem cells. Here, we describe a recently evolved pathway in which global hypomethylation is achieved by the coupling of active and passive demethylation. TET activity is required, albeit indirectly, for global demethylation, which mostly occurs at sites devoid of TET binding. Instead, TET-mediated active demethylation is locus-specific and necessary for activating a subset of genes, including the naïve pluripotency and germline marker Dppa3 (Stella, Pgc7). DPPA3 in turn drives large-scale passive demethylation by directly binding and displacing UHRF1 from chromatin, thereby inhibiting maintenance DNA methylation. Although unique to mammals, we show that DPPA3 alone is capable of inducing global DNA demethylation in non-mammalian species (Xenopus and medaka) despite their evolutionary divergence from mammals more than 300 million years ago. Our findings suggest that the evolution of Dppa3 facilitated the emergence of global DNA demethylation in mammals.

6.
J Vis Exp ; (163)2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-33044457

RESUMO

Membrane proteins play essential roles in a variety of cellular processes and perform vital functions. Membrane proteins are medically important in drug discovery because they are the targets of more than half of all drugs. An obstacle to conducting biochemical, biophysical, and structural studies of membrane proteins as well as antibody development has been the difficulty in producing large amounts of high-quality membrane protein with correct conformation and activity. Here we describe a "bilayer-dialysis method" using a wheat germ cell-free system, liposomes, and dialysis cups to efficiently synthesize membrane proteins and prepare purified proteoliposomes in a short time with a high success rate. Membrane proteins can be produced as much as in several milligrams, such as GPCRs, ion channels, transporters, and tetraspanins. This cell-free method contributes to reducing the time, cost and effort for preparing high-quality proteoliposomes, and provides suitable means for functional analysis of membrane proteins, drug targets screening, and antibody development.

7.
Sci Rep ; 10(1): 13562, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782316

RESUMO

NLRP3, an intracellular pattern recognition receptor, recognizes numerous pathogens and/or its own damage-associated molecules, and forms complexes with the adaptor protein ASC. These complexes constitute the NLRP3 inflammasome, a platform for processing interleukin (IL)-1ß and/or IL-18. Several NLRP3 mutations result in constitutive activation of the NLRP3 inflammasome, causing cryopyrin-associated periodic syndrome (CAPS). To the best of our knowledge, small compounds that specifically inhibit inflammasome activation through the pyrin domain (PYD) have not yet been developed. This study describes an attempt to develop small compounds targeting the NLRP3 inflammasome. A core chemical library of 9,600 chemicals was screened against reconstituted NLRP3 inflammasome in a cell-free system with an amplified luminescence proximity homogeneous assay and a cell-based assay by human peripheral blood mononuclear cells (PBMCs). Inflammasome activation was evaluated by ASC-speck formation in human PBMCs, accompanied by IL-1ß secretion and processing, and by using IL-1ß-based dual operating luciferase (IDOL) mice. The activity of these compounds was evaluated clinically using PBMCs from a patient with Muckle-Wells syndrome (MWS), a type of CAPS, with an R260W mutation in NLRP3. Screening identified KN3014, a piperidine-containing compound targeting the interaction between NLRP3 and ASC through the PYD. KN3014 reduced ASC-speck formation in human PBMCs, luminescence from IDOL mice, and auto-secretion of IL-1ß by PBMCs from the patient with MWS. These findings suggest that KN3014 may be an attractive candidate for treatment of MWS, as well as other NLRP3 inflammasomopathies.

8.
PLoS One ; 15(4): e0229196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294099

RESUMO

Citrus mosaic virus (CiMV) is one of the causal viruses of citrus mosaic disease in satsuma mandarins (Citrus unshiu). Prompt detection of trees infected with citrus mosaic disease is important for preventing the spread of this disease. Although rabbit monoclonal antibodies (mAbs) exhibit high specificity and affinity, their applicability is limited by technical difficulties associated with the hybridoma-based technology used for raising these mAbs. Here, we demonstrate a feasible CiMV detection system using a specific rabbit mAb against CiMV coat protein. A conserved peptide fragment of the small subunit of CiMV coat protein was designed and used to immunize rabbits. Antigen-specific antibody-producing cells were identified by the immunospot array assay on a chip method. After cloning of variable regions in heavy or light chain by RT-PCR from these cells, a gene set of 33 mAbs was constructed and these mAbs were produced using Expi293F cells. Screening with the AlphaScreen system revealed eight mAbs exhibiting strong interaction with the antigen peptide. From subsequent sequence analysis, they were grouped into three mAbs denoted as No. 4, 9, and 20. Surface plasmon resonance analysis demonstrated that the affinity of these mAbs for the antigen peptide ranged from 8.7 × 10-10 to 5.5 × 10-11 M. In addition to CiMV, mAb No. 9 and 20 could detect CiMV-related viruses in leaf extracts by ELISA. Further, mAb No. 20 showed a high sensitivity to CiMV and CiMV-related viruses, simply by dot blot analysis. The anti-CiMV rabbit mAbs obtained in this study are envisioned to be extremely useful for practical applications of CiMV detection, such as in a virus detection kit.


Assuntos
Anticorpos Monoclonais/biossíntese , Citrus/virologia , Vírus do Mosaico/isolamento & purificação , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Especificidade de Anticorpos/imunologia , Proteínas do Capsídeo/imunologia , Cinética , Folhas de Planta/virologia , Coelhos
9.
Mol Genet Genomic Med ; 8(3): e1107, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31883238

RESUMO

BACKGROUND: Variants in the LZTR1 (leucine-zipper-like transcription regulator 1) gene (OMIM #600574) have been reported in recessive Noonan syndrome patients. In vivo evidence from animal models to support its causative role is lacking. METHODS: By CRISPR-Cas9 genome editing, we generated lztr1-mutated zebrafish (Danio rerio). Analyses of histopathology and downstream signaling were performed to investigate the pathogenesis of cardiac and extracardiac abnormalities in Noonan syndrome. RESULTS: A frameshift deletion allele was created in the zebrafish lztr1. Crosses of heterozygotes obtained homozygous lztr1 null mutants that modeled LZTR1 loss-of-function. Histological analyses of the model revealed ventricular hypertrophy, the deleterious signature of Noonan syndrome-associated cardiomyopathy. Further, assessment for extracardiac abnormalities documented multiple vascular malformations, resembling human vascular pathology caused by RAS/MAPK activation. Due to spatiotemporal regulation of LZTR1, its downstream function was not fully elucidated from western blots of adult tissue. CONCLUSION: Our novel zebrafish model phenocopied human recessive Noonan syndrome and supported the loss-of-function mechanism of disease-causing LZTR1 variants. The discovery of vascular malformations in mutants calls for the clinical follow-up of patients to monitor for its emergence. The model will serve as a novel platform for investigating the pathophysiology linking RAS/MAPK signaling to cardiac and vascular pathology.

10.
Zoological Lett ; 5: 33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807314

RESUMO

The relationship between development and evolution has been a central theme in evolutionary developmental biology. Across the vertebrates, the most highly conserved gene expression profiles are found at mid-embryonic, organogenesis stages, whereas those at earlier and later stages are more diverged. This hourglass-like pattern of divergence does not necessarily rule out the possibility that gene expression profiles that are more evolutionarily derived appear at later stages of development; however, no molecular-level evidence of such a phenomenon has been reported. To address this issue, we compared putative gene regulatory elements among different species within a phylum. We made a genome-wide assessment of accessible chromatin regions throughout embryogenesis in three vertebrate species (mouse, chicken, and medaka) and estimated the evolutionary ages of these regions to define their evolutionary origins on the phylogenetic tree. In all the three species, we found that genomic regions tend to become accessible in an order that parallels their phylogenetic history, with evolutionarily newer gene regulations activated at later developmental stages. This tendency was restricted only after the mid-embryonic, phylotypic periods. Our results imply a phylogenetic hierarchy of putative regulatory regions, in which their activation parallels the phylogenetic order of their appearance. One evolutionary mechanism that may explain this phenomenon is that newly introduced regulatory elements are more likely to survive if activated at later stages of embryogenesis. Possible relationships between this phenomenon and the so-called recapitulation are discussed.

11.
Genome Biol Evol ; 11(11): 3144-3157, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31621849

RESUMO

Since its initial publication in 2002, the genome of Ciona intestinalis type A (Ciona robusta), the first genome sequence of an invertebrate chordate, has provided a valuable resource for a wide range of biological studies, including developmental biology, evolutionary biology, and neuroscience. The genome assembly was updated in 2008, and it included 68% of the sequence information in 14 pairs of chromosomes. However, a more contiguous genome is required for analyses of higher order genomic structure and of chromosomal evolution. Here, we provide a new genome assembly for an inbred line of this animal, constructed with short and long sequencing reads and Hi-C data. In this latest assembly, over 95% of the 123 Mb of sequence data was included in the chromosomes. Short sequencing reads predicted a genome size of 114-120 Mb; therefore, it is likely that the current assembly contains almost the entire genome, although this estimate of genome size was smaller than previous estimates. Remapping of the Hi-C data onto the new assembly revealed a large inversion in the genome of the inbred line. Moreover, a comparison of this genome assembly with that of Ciona savignyi, a different species in the same genus, revealed many chromosomal inversions between these two Ciona species, suggesting that such inversions have occurred frequently and have contributed to chromosomal evolution of Ciona species. Thus, the present assembly greatly improves an essential resource for genome-wide studies of ascidians.


Assuntos
Inversão Cromossômica , Ciona intestinalis/genética , Evolução Molecular , Animais , Cordados não Vertebrados , Genoma , Filogenia
12.
Case Rep Oncol ; 12(2): 666-670, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572156

RESUMO

Dural metastases are uncommon in cancer patients, but can have as much of an effect on the lives of patients as brain metastases. Dural metastases are most commonly associated with primary cancers of the breast, prostate, and lung, and it is rare that the primary site of the tumor is unknown. In this study, we encountered a 51-year-old woman who had developed multiple bone tumors, with no known primary cancer lesion. A tumor biopsy of the sacral bone revealed non-keratinizing squamous cell carcinoma; the patient was therefore diagnosed as having multiple bone metastases of an unknown primary cancer. Magnetic resonance imaging revealed cranial metastases and partial thickening of the dura with suspected dura metastases. Platinum-based chemotherapy reduced the bone metastases and the thickened dura. However, as resistance to chemotherapy developed, invasions progressed rapidly and diffusely throughout the dura. This was accompanied by the development of dysarthria, visual impairments, and delirium. The patient died 10 months after being diagnosed with dural metastases. This report provides information on the clinical course and prognosis of patients with dural metastases of unknown primary cancer. Furthermore, it may help to construct a treatment strategy for dural metastases.

13.
Biochem Biophys Res Commun ; 518(1): 183-189, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31421830

RESUMO

Brefeldin A-inhibited guanine nucleotide-exchange protein 3 (BIG3) interacts with and inhibits the tumor suppressor function of prohibitin-2 (PHB2), and recent in vivo studies have demonstrated that the BIG3-PHB2 interaction is a promising target for breast cancer therapy. However, little biophysical characterization on BIG3 and its interaction with PHB2 has been reported. Here we compared the calculated 8-class secondary structure of the N-terminal domains of BIG family proteins and identified a loop region unique to BIG3. Our biophysical characterization demonstrated that this loop region significantly affects the colloidal and thermodynamic stability of BIG3 and the thermodynamic and kinetic profile of its interaction with PHB2. These results establish a model for the BIG3-PHB2 interaction and an entry for drug discovery for breast cancer.


Assuntos
Fenômenos Biofísicos , Neoplasias da Mama/metabolismo , Sequência Conservada , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Coloides/química , Feminino , Humanos , Cinética , Modelos Biológicos , Ligação Proteica , Domínios Proteicos , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Temperatura
14.
Front Chem ; 7: 418, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31245355

RESUMO

The visible-light responsive Cu(I)-complex photosensitizers were developed by introducing various aromatic substituents at the 4,7-positions of a 2,9-dimethyl-1,10-phenanthroline (dmp) ligand in a heteroleptic CuI(dmp)(DPEphos)+-type complexes (DPEphos = [2-(diphenylphosphino)phenyl]ether) for photocatalytic CO2 reduction. Introducing biphenyl groups (Bp-) on the dmp ligand enhanced the molar extinction coefficient (ε) of the metal-to-ligand charge transfer (MLCT) band in the visible region (ε = 7,500 M-1cm-1) compared to that of the phenyl (Ph-)-containing analog (ε = 5,700 M-1cm-1 at λmax = 388 nm). However, introducing 4-R-Ph- groups (R = the electron-withdrawing groups NC-, or NO2-) led to a red shift in the band to λmax = 390, 400, and 401 nm, respectively. Single-crystal X-ray analysis showed the Ph- groups were twisted because of the steric repulsion between the 2,6-protons of the Ph- groups and 5,6-protons of the dmp ligand. The result strongly indicated that the π-conjugation effect of the 4-R-Ph- groups is so weak that the lowering of the energy of the dmp π* orbitals is small. However, when 4-R-ph- was substituted by a 5-membered heterorings, there was a larger red shift, leading to an increase in the ε value of the MLCT absorption band. Thus, the substitution to 2-benzofuranyl- groups resulted in visible-light absorption up to 500 nm and a shoulder peak at around 420 nm (ε = 12,300 M-1cm-1) due to the expansion of π-conjugation over the substituted dmp ligand. The photocatalytic reaction for CO2 reduction was tested using the obtained CuI complexes as photosensitizers in the presence of a Fe(dmp)2(NCS)2 catalyst and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole as a sacrificial reductant, which showed improved CO generation.

15.
Cell Rep ; 27(3): 928-939.e4, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30995487

RESUMO

Establishment of robust gene expression boundary is crucial for creating elaborate morphology during development. However, mechanisms underlying boundary formation have been extensively studied only in a few model systems. We examined the establishment of zic1/zic4-expression boundary demarcating dorsoventral boundary of the entire trunk of medaka fish (Oryzias latipes) and identified a subgroup of dermomyotomal cells called horizontal boundary cells (HBCs) as crucial players for the boundary formation. Embryological and genetic analyses demonstrated that HBCs play crucial roles in the two major events of the process, i.e., refinement and maintenance. In the refinement, HBCs could serve as a chemical barrier against Wnts from the neural tube by expressing Hhip. At later stages, HBCs participate in the maintenance of the boundary by differentiating into the horizontal myoseptum physically inhibiting cell mixing across the boundary. These findings reveal the mechanisms underlying the dorsoventral boundary in the teleost trunk by specialized boundary cells.


Assuntos
Proteínas de Peixes/metabolismo , Somitos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Padronização Corporal/genética , Diferenciação Celular , Cromossomos Artificiais Bacterianos/genética , Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Oryzias/metabolismo , Somitos/citologia , Fatores de Transcrição/genética , Peixe-Zebra/metabolismo
16.
Epigenetics Chromatin ; 12(1): 17, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871638

RESUMO

BACKGROUND: Epigenetic modifications have a central role in transcriptional regulation. While several studies using next-generation sequencing have revealed genome-wide associations between epigenetic modifications and transcriptional states, a direct causal relationship at specific genomic loci has not been fully demonstrated, due to a lack of technology for targeted manipulation of epigenetic modifications. Recently, epigenome editing techniques based on the CRISPR-Cas9 system have been reported to directly manipulate specific modifications at precise genomic regions. However, the number of editable modifications as well as studies applying these techniques in vivo is still limited. RESULTS: Here, we report direct modification of the epigenome in medaka (Japanese killifish, Oryzias latipes) embryos. Specifically, we developed a method to ectopically induce the repressive histone modification, H3K27me3 in a locus-specific manner, using a fusion construct of Oryzias latipes H3K27 methyltransferase Ezh2 (olEzh2) and dCas9 (dCas9-olEzh2). Co-injection of dCas9-olEzh2 mRNA with single guide RNAs (sgRNAs) into one-cell-stage embryos induced specific H3K27me3 accumulation at the targeted loci and induced downregulation of gene expression. CONCLUSION: In this study, we established the in vivo epigenome editing of H3K27me3 using medaka embryos. The locus-specific manipulation of the epigenome in living organisms will lead to a previously inaccessible understanding of the role of epigenetic modifications in development and disease.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Edição de Genes/métodos , Histonas/metabolismo , Oryzias/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Embrião não Mamífero , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Metilação , Oryzias/genética , RNA Guia
17.
J Am Chem Soc ; 140(49): 17241-17254, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30481014

RESUMO

The development of highly efficient, selective, and durable photocatalytic CO2 reduction systems that only use earth-abundant elements is key for both solving global warming and tackling the shortage of energy and carbon resources. Here, we successfully developed CO2 reduction photocatalysts using [Cu2(P2bph)2]2+ (CuPS) (P2bph = 4,7-diphenyl-2,9-di(diphenylphosphinotetramethylene)-1,10-phenanthroline) as a redox photosensitizer and fac-Mn(X2bpy)(CO)3Br (Mn(4X)) (X2bpy = 4,4'-X2-2,2'-bipyridine (X = -H and -OMe) or Mn(6mes) (6mes = 6,6'-(mesityl)2-2,2'-bipyridne)) as the catalyst. The most efficient photocatalysis was achieved by Mn(4OMe): The total quantum yield of CO2 reduction products was 57%, the turnover number based on the Mn catalyst was over 1300, and the selectivity of CO2 reduction was 95%. Electronic and steric effects of the substituents (X) in the Mn complexes largely affected both the photocatalytic efficiency and the product selectivity. For example, the highest selectivity of CO formation was achieved by using Mn(6mes) (selectivity SCO = 96.6%), whereas the photocatalytic system using Mn(4H) yielded HCOOH as the main product ( SHCOOH = 74.6%) with CO and H2 as minor products ( SCO = 23.7%, SH2 = 1.7%). In these photocatalytic reactions, CuPS played its role as an efficient and very durable redox photosensitizer, while remaining stable in the reaction solution even after a turnover number of 200 had been reached (the catalyst used had a turnover number of over 1000).

18.
Inflamm Regen ; 38: 27, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30459926

RESUMO

Background: Alzheimer's disease is a neurodegenerative disease characterized by the interstitial deposition of amyloid ß (Aß) plaque, which is thought to be related to chronic neuroinflammation. Aß is known to make fibrils via oligomers from monomers. Aß has been reported to activate the NLRP3 inflammasome in infiltrated macrophages. NLRP3, an intracellular pattern recognition receptor, has been reported to recognize numerous pathogens and/or metabolites and form complexes with adopter protein ASC to make the inflammasome, an interleukin (IL)-1ß-processing platform. Although reactive oxygen species from mitochondria have been reported to be involved in the activation of the NLRP3 inflammasome in microglial cells upon the deposition of Aß, whether Aß directly or indirectly activates the NLRP3 inflammasome remains unclear. Methods: We prepared monomers, oligomers, and fibrils of Aß, which promoted the interaction between NLRP3 and each form of Aß and analyzed the interaction between NLRP3 and ASC induced by each form of Aß in a cell-free system with the amplified luminescent proximity homogeneous assay. We also confirmed the physiological relevance in a cell-based assay using human embryonic kidney 293T cells and human peripheral mononuclear cells. Results: Monomers, oligomers, and fibrils of Aß were successfully prepared. Aß oligomers and fibrils interacted with NLRP3. Aß oligomers and fibrils induced the interaction between NLRP3 and ASC. However, Aß monomers did not interact with NLRP3 or induce interaction between NLRP3 and ASC in the cell-free system, and IL-1ß was not secreted according to the cell-based assay. Conclusion: Oligomerized Aß originating from non-toxic Aß monomers directly interacted with NLRP3, leading to the activation of the NLRP3 inflammasome. This may be an attractive target for the treatment of Alzheimer's disease.

19.
Methods Mol Biol ; 1868: 49-67, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30244454

RESUMO

Antibodies specifically recognizing integral membrane protein are essential tool for functional analysis, diagnosis, and therapeutics targeting membrane proteins. However, development of antibodies against membrane protein remains a big challenge, because mass production of membrane protein is difficult. Recently, we developed a highly efficient cell-free production method of proteoliposome antigen using cell-free protein synthesis method with liposome and dialysis cup. Here we introduce practical and efficient integrated procedures to produce large amount of proteoliposome antigen for anti-membrane protein antibody development.


Assuntos
Antígenos/metabolismo , Imunização , Biologia Molecular/métodos , Biossíntese de Proteínas , Proteolipídeos/metabolismo , Adjuvantes Imunológicos/farmacologia , Sistema Livre de Células , Bicamadas Lipídicas/metabolismo , Proteínas de Membrana/metabolismo , Plasmídeos/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo
20.
Methods Mol Biol ; 1868: 93-112, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30244457

RESUMO

Autoantibodies that recognize self-antigens are believed to have close relationship diseases such as autoimmune diseases, cancer, and lifestyle diseases. Analysis of autoantibodies is essential for investigating pathology mechanisms, diagnosis, and therapeutics of these diseases. We developed autoantibody profiling assay using cell-free synthesized protein array and high-throughput screening technology. Our assay system can sensitively detect interaction between recombinant antigen protein and autoantibody and efficiently analyze autoantibody profiling in patients' sera.


Assuntos
Autoanticorpos/metabolismo , Autoantígenos/metabolismo , Análise Serial de Proteínas/métodos , Sequência de Bases , Neoplasias da Mama/sangue , Feminino , Humanos , Biossíntese de Proteínas , Transcrição Genética
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