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1.
Angew Chem Int Ed Engl ; 62(35): e202307532, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37401836

RESUMEN

A gold-catalyzed cascade cyclization of naphthalene-tethered allenynes gave strained fused phenanthrene derivatives. The reaction proceeds through the nucleophilic reaction of an alkyne with the activated allene to generate a vinyl cation intermediate, followed by arylation with a tethered naphthalene ring to form the 4H-cyclopenta[def]phenanthrene (CPP) scaffold. When using aryl-substituted substrates on the alkyne terminus, the gold-catalyzed reaction produced dibenzofluorene derivatives along with the CPP derivatives. Selective formation of CPP and dibenzofluorene derivatives depending on the reaction conditions is also presented.

2.
J Neural Transm (Vienna) ; 130(4): 513-520, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871130

RESUMEN

Both cerebrospinal fluid (CSF) homovanillic acid (HVA) and striatal dopamine transporter (DAT) binding on single-photon emission computed tomography (SPECT) reflect nigrostriatal dopaminergic function, but studies on the relationship between the two have been limited. It is also unknown whether the reported variance in striatal DAT binding among diseases reflects the pathophysiology or characteristics of the subjects. We included 70 patients with Parkinson's disease (PD), 12 with progressive supranuclear palsy (PSP), 12 with multiple system atrophy, six with corticobasal syndrome, and nine with Alzheimer's disease as disease control, who underwent both CSF analysis and 123I-N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl)nortropane (123I-ioflupane) SPECT. We evaluated the correlation between CSF HVA concentration and the specific binding ratio (SBR) of striatal DAT binding. We also compared the SBR for each diagnosis, controlling for CSF HVA concentration. The correlations between the two were significant in patients with PD (r = 0.34, p = 0.004) and PSP (r = 0.77, p = 0.004). The mean SBR value was the lowest in patients with PSP and was significantly lower in patients with PSP than in those with PD (p = 0.037) after adjusting for CSF HVA concentration. Our study demonstrates that striatal DAT binding correlates with CSF HVA concentration in both PD and PSP, and striatal DAT reduction would be more advanced in PSP than in PD at an equivalent dopamine level. Striatal DAT binding may correlate with dopamine levels in the brain. The pathophysiology of each diagnosis may explain this difference.


Asunto(s)
Enfermedad de Parkinson , Trastornos Parkinsonianos , Humanos , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Ácido Homovanílico , Dopamina/metabolismo , Trastornos Parkinsonianos/diagnóstico por imagen , Trastornos Parkinsonianos/metabolismo , Tomografía Computarizada de Emisión de Fotón Único/métodos
3.
Neurology ; 100(10): e1009-e1019, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36517236

RESUMEN

BACKGROUND AND OBJECTIVES: CSF tau phosphorylated at threonine 181 (p-tau181) is a widely used biomarker for Alzheimer disease (AD) and has recently been regarded to reflect ß-amyloid and/or p-tau deposition in the AD brain. Neuronal intranuclear inclusion disease (NIID) is a neurodegenerative disease characterized by intranuclear inclusions in neurons, glial cells, and other somatic cells. Symptoms include dementia, neuropathy, and others. CSF biomarkers were not reported. The objective of this study was to investigate whether CSF biomarkers including p-tau181 are altered in patients with NIID. METHODS: This was a retrospective observational study. CSF concentrations of p-tau181, total tau, amyloid-beta 1-42 (Aß42), monoamine metabolites homovanillic acid (HVA), and 5-hydroxyindole acetic acid (5-HIAA) were compared between 12 patients with NIID, 120 patients with Alzheimer clinical syndrome biologically confirmed based on CSF biomarker profiles, and patients clinically diagnosed with other neurocognitive disorders (dementia with Lewy bodies [DLB], 24; frontotemporal dementia [FTD], 13; progressive supranuclear palsy [PSP], 21; and corticobasal syndrome [CBS], 13). Amyloid PET using Pittsburgh compound B (PiB) was performed in 6 patients with NIID. RESULTS: The mean age of patients with NIID, AD, DLB, FTD, PSP, and CBS was 71.3, 74.6, 76.8, 70.2, 75.5, and 71.9 years, respectively. CSF p-tau181 was significantly higher in NIID (72.7 ± 24.8 pg/mL) compared with DLB, PSP, and CBS and was comparable between NIID and AD. CSF p-tau181 was above the cutoff value (50.0 pg/mL) in 11 of 12 patients with NIID (91.7%). Within these patients, only 2 patients showed decreased CSF Aß42, and these patients showed negative or mild local accumulation in PiB PET, respectively. PiB PET scans were negative in the remaining 4 patients tested. The proportion of patients with increased CSF p-tau181 and normal Aß42 (A-T+) was significantly higher in NIID (75%) compared with DLB, PSP, and CBS (4.2%, 4.8%, and 7.7%, respectively). CSF HVA and 5-HIAA concentrations were significantly higher in patients with NIID compared with disease controls. DISCUSSION: CSF p-tau181 was increased in patients with NIID without amyloid accumulation. Although the deposition of p-tau has not been reported in NIID brains, the molecular mechanism of tau phosphorylation or secretion of p-tau may be altered in NIID.


Asunto(s)
Enfermedad de Alzheimer , Demencia Frontotemporal , Enfermedades Neurodegenerativas , Enfermedad de Pick , Humanos , Enfermedades Neurodegenerativas/diagnóstico por imagen , Cuerpos de Inclusión Intranucleares , Proteínas tau , Demencia Frontotemporal/diagnóstico , Ácido Hidroxiindolacético , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides , Biomarcadores , Fragmentos de Péptidos
4.
Hortic Res ; 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35043178

RESUMEN

Target activation-induced cytidine deaminase (Target-AID), a novel CRISPR/Cas9-based genome-editing tool, confers the base-editing capability on the Cas9 genome-editing system. It involves the fusion of cytidine deaminase (CDA), which catalyzes cytidine (C) to uridine (U) substitutions, to the mutated nickase-type nCas9 or deactivated-type dCas9. To confirm and extend the applicability of the Target-AID genome-editing system in tomatoes (Solanum lycopersicum L.), we transformed the model tomato cultivar "Micro-Tom" and commercial tomato cultivars using this system by targeting SlDELLA, which encodes a negative regulator of the plant phytohormone gibberellic acid (GA) signaling pathway. We confirmed that the nucleotide substitutions were induced by the Target-AID system, and we isolated mutants showing high GA sensitivity in both "Micro-Tom" and the commercial cultivars. Moreover, by successfully applying this system to ETHYLENE RECEPTOR 1 (SlETR1) with single sgRNA targeting, double sgRNA targeting, as well as dual-targeting of both SlETR1 and SlETR2 with a single sgRNA, we demonstrated that the Target-AID genome-editing system is a promising tool for molecular breeding in tomato crops. This study highlights an important aspect of the scientific and agricultural potential of the combinatorial use of the Target-AID and other base-editing systems.

5.
Angew Chem Int Ed Engl ; 60(52): 27019-27025, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34590766

RESUMEN

A novel approach to the direct construction of tricyclic nitrogen heterocycles based on gold-catalyzed cascade cyclization of aminoallenynes is described. The expected biscyclization reaction of hydroxyisobutyryl-protected aminoallenynes was efficiently promoted by a catalytic amount of BrettPhosAuNTf2 in the presence of iPrOH to produce 1,2-dihydrobenzo[cd]indole derivatives in good yields. When the reaction was combined with Friedel-Crafts acylation or palladium-catalyzed N-arylation, the resulting tricyclic products were efficiently converted into nitrogen-containing polycyclic aromatic compounds (N-PACs) with highly conjugated π-electron systems. A newly obtained hexacyclic indolium salt showed characteristic concentration-dependent absorption and emission properties.

6.
Plant Biotechnol (Tokyo) ; 37(2): 213-221, 2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32821229

RESUMEN

The CRISPR/Cas9 system is widely used for targeted mutagenesis in many organisms including plants. For application of this system, tissue culture methods need to be established. In this study, detailed methods for introduction of mutations in tomato and Nicotiana benthamiana plants using the CRISPR/Cas9 system are described. The methods include tissue culture protocols for tomato and N. benthamiana. We also demonstrate the methodology to generate Cas9-free genome edited tomato plants and use of one single guide RNA (sgRNA) to edit two orthologs in N. benthamiana. The examples of editing the PHYTOENE DESATURASE (PDS) genes in these plants are also provided. The Cas9-free tomato line was obtained when tomato plants were cultured on a non-selective medium after transformation with the CRISPR/Cas9 system. Two orthologs of PDS in N. benthamiana were mutated using a sgRNA, because these orthologs contain the same nucleotide sequences with PAM motif. These mutations were inherited to the next generation. The mutations in the PDS genes resulted in an albino phenotype in tomato and N. benthamiana plants. These results demonstrate that the non-selective method is one of the ways to obtain Cas9-free genome editing in tomato plants and that the two orthologs can be edited by one sgRNA in N. benthamiana.

7.
Nat Biotechnol ; 35(5): 441-443, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28346401

RESUMEN

We applied a fusion of CRISPR-Cas9 and activation-induced cytidine deaminase (Target-AID) for point mutagenesis at genomic regions specified by single guide RNAs (sgRNAs) in two crop plants. In rice, we induced multiple herbicide-resistance point mutations by multiplexed editing using herbicide selection, while in tomato we generated marker-free plants with homozygous heritable DNA substitutions, demonstrating the feasibility of base editing for crop improvement.


Asunto(s)
Proteínas Asociadas a CRISPR/genética , ADN de Plantas/genética , Edición Génica/métodos , Mutagénesis Sitio-Dirigida/métodos , Oryza/genética , Solanum lycopersicum/genética , Emparejamiento Base/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Citidina Desaminasa/genética , Genes de Plantas/genética , Plantas Modificadas Genéticamente/genética , Mutación Puntual/genética , Proteínas Recombinantes de Fusión/genética
8.
Int Heart J ; 47(4): 511-9, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16960406

RESUMEN

Although an association between Chlamydia pneumoniae (Cpn) or Cytomegalovirus (CMV) infection and coronary atherosclerosis has been reported, such an association is less clear for acute coronary syndromes (ACS). The purpose of this study was to investigate the pathogenic roles of Cpn and CMV infection of coronary plaques in ACS. We divided 38 coronary plaque specimens obtained from 38 patients who underwent directional coronary atherectomy or thrombectomy into an ACS group (n = 21) and a non-ACS group (n = 17). Cpn and CMV in specimens were stained using immunohistochemical techniques and analyzed quantitatively. The detection rate for either Cpn- or CMV-positive cells in ACS patients was slightly higher compared with non-ACS patients. Detection rates for both Cpn- and CMV-positive cells were significantly higher in ACS patients than in non-ACS patients (P = 0.010). Furthermore, the density of Cpn- and CMV-positive cells in plaques was significantly higher in ACS patients than in non-ACS patients (P < 0.003). The results indicate that the presence and severity of Cpn and CMV infection in coronary plaques are greater in patients with ACS compared with non-ACS patients. We conclude that infection with Cpn and CMV in coronary plaques may be involved in the pathogenesis of ACS.


Asunto(s)
Infecciones por Chlamydophila/complicaciones , Chlamydophila pneumoniae/inmunología , Enfermedad de la Arteria Coronaria/complicaciones , Trombosis Coronaria/etiología , Infecciones por Citomegalovirus/complicaciones , Citomegalovirus/inmunología , Anciano , Anticuerpos Antibacterianos/análisis , Anticuerpos Antivirales/análisis , Aterectomía Coronaria/métodos , Infecciones por Chlamydophila/diagnóstico , Infecciones por Chlamydophila/microbiología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/microbiología , Enfermedad de la Arteria Coronaria/cirugía , Enfermedad de la Arteria Coronaria/virología , Trombosis Coronaria/diagnóstico , Trombosis Coronaria/cirugía , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/virología , Electrocardiografía , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Rotura Espontánea , Síndrome , Trombectomía/métodos
9.
Am Heart J ; 150(4): 681-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16209964

RESUMEN

BACKGROUND: An association between Chlamydia pneumoniae (Cpn) infection and coronary artery disease has been reported and examined by different techniques. However, its immunoreactivity in coronary artery plaques of patients with acute coronary syndrome (ACS) and its relation with serology are less well defined. METHODS: We divided 40 coronary plaque specimens from 40 patients who underwent thrombectomy or directional coronary atherectomy into an ACS group (n = 22) and a non-ACS group (n = 18). Cpn in specimens was detected immunohistochemically and compared quantitatively. Serum immunoglobulin (Ig)A and IgG antibodies to Cpn and high-sensitivity C-reactive protein (hs-CRP) were measured. The relation between serology and immunohistochemical analysis was also investigated. RESULTS: Cpn immunopositive cells per square millimeter (Cpn+ cells/mm2) in the ACS group were significantly more numerous than in the non-ACS group (median 7.44 vs 1.50, P = .0018). Cpn IgA seropositivity rates and titers in the ACS group were significantly higher than those in the non-ACS group (86.3% vs 22.2%, P = .0002; median titer 1.403 vs 0.545, P = .003). There were no differences in IgG antibodies between the 2 groups. The hs-CRP values (in milligrams per liter) in ACS group were significantly higher than in non-ACS group (median 2.8 vs 1.2, P = .0019). Serum IgA titers in patients with at least 5 Cpn+ cells/mm2 in the specimens were significantly higher than in patients with fewer Cpn+ cells (median 1.52 vs 0.86, P = .026). There was no difference in serum hs-CRP values in patients with more Cpn+ cells but a trend to an increase. CONCLUSION: Immunohistology frequently detected Cpn in coronary plaques; Cpn+ cells were more prevalent in plaques associated with ACS, and Cpn IgA but not IgG titers were increased with ACS and with high densities of Cpn+ cells within plaque.


Asunto(s)
Angina Inestable/inmunología , Infecciones por Chlamydophila/inmunología , Chlamydophila pneumoniae/inmunología , Enfermedad de la Arteria Coronaria/inmunología , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Infarto del Miocardio/inmunología , Enfermedad Aguda , Anciano , Angina Inestable/sangre , Infecciones por Chlamydophila/sangre , Enfermedad de la Arteria Coronaria/sangre , Femenino , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Pruebas Serológicas , Síndrome
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