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1.
Beilstein J Org Chem ; 11: 1561-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26664576

RESUMEN

Chiral molecular crystals built up by chiral molecules without inversion centers have attracted much interest owing to their versatile functionalities related to optical, magnetic, and electrical properties. However, there is a difficulty in chiral crystal growth due to the lack of symmetry. Therefore, we made the molecular design to introduce intermolecular hydrogen bonds in chiral crystals. Racemic and enantiopure bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) derivatives possessing hydroxymethyl groups as the source of hydrogen bonds were designed. The novel racemic trans-vic-(hydroxymethyl)(methyl)-BEDT-TTF 1, and racemic and enantiopure trans-vic-bis(hydroxymethyl)-BEDT-TTF 2 were synthesized. Moreover, the preparations, crystal structure analyses, and electrical resistivity measurements of the novel achiral charge transfer salt θ(21)-[(S,S)-2]3[(R,R)-2]3(ClO4)2 and the chiral salt α'-[(R,R)-2]ClO4(H2O) were carried out. In the former θ(21)-[(S,S)-2]3[(R,R)-2]3(ClO4)2, there are two sets of three crystallographically independent donor molecules [(S,S)-2]2[(R,R)-2] in a unit cell, where the two sets are related by an inversion center. The latter α'-[(R,R)-2]ClO4(H2O) is the chiral salt with included solvent H2O, which is not isostructural with the reported chiral salt α'-[(S,S)-2]ClO4 without H2O, but has a similar donor arrangement. According to the molecular design by introduction of hydroxy groups and a ClO4 (-) anion, many intermediate-strength intermolecular hydrogen bonds (2.6-3.0 Å) were observed in these crystals between electron donor molecules, anions, and included H2O solvent, which improve the crystallinity and facilitate the extraction of physical properties. Both salts are semiconductors with relatively low resistivities at room temperature and activation energies of 1.2 ohm cm with E a = 86 meV for θ(21)-[(S,S)-2]3[(R,R)-2]3(ClO4)2 and 0.6 ohm cm with E a = 140 meV for α'-[(R,R)-2]2ClO4(H2O), respectively. The variety of donor arrangements, θ(21) and two kinds of α'-types, and their electrical conductivities of charge transfer complexes based upon the racemic and enantiopure (S,S)-2, and (R,R)-2 donors originates not only from the chirality, but also the introduced intermolecular hydrogen bonds involving the hydroxymethyl groups, perchlorate anion, and the included solvent H2O.

2.
Fukushima J Med Sci ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38925956

RESUMEN

5-Aminolevulinic acid (5-ALA) is orally administered 2-4 hours before surgery to identify tumor location. Hypotension is sometimes observed after 5-ALA administration. Case reoprtWe present a case of a patient with 5-ALA-induced hypotension that resulted in the development of cerebral infarction. An 83-year-old man with a bladder tumor was scheduled for photodynamic diagnosis-assisted transurethral resection of bladder tumor (PDD-TURBT) and right radical nephroureterectomy. 5-ALA was orally administered and his ordinary antihypertensive and antianginal agents were also administered an hour after 5-ALA administration. Following this, his blood pressure dropped, and he developed muscle weakness and paralysis in his left upper extremity. Magnetic resonance imaging showed evidence of cerebral infarction. ConclusionsWe cannot conclude definitively that our patient's cerebral infarction was solely caused by 5-ALA-induced hypotension because hypotension under these circumstances is not rare. We consider that additional factors, such as patient-specific doses of antihypertensive and antianginal agents may have played a role in the development of his cerebral infarction.

3.
Nanomaterials (Basel) ; 14(1)2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38202518

RESUMEN

Porous structures and micropatterning surfaces play a crucial role in the development of highly sensitive force sensors. However, achieving these two conductive architectures typically requires the synthesis of complex materials and expensive manufacturing processes. In this study, we introduce a novel conductive composite film featuring a microporous/micropyramid hybrid conductive architecture, which is achieved through a straightforward process of materials mixing and one-step screen printing. By utilizing a deep eutectic solvent in the ink component, micropores are induced in the printed composite, while the mesh of the screen mask acts as a template, resulting in a micropyramid film surface. We have successfully realized highly sensitive flexible force sensors (0.15 kPa-1) with multifunctional capabilities for perceiving normal force and shear force.

4.
Vaccine ; 40(6): 862-872, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34998604

RESUMEN

Transcutaneous immunization (TCI) is an effective vaccination method that is easier and less painful than the conventional injectable vaccination method. We previously developed self-dissolving microneedle patches (sdMN) and demonstrated that this TCI method has a high vaccination efficacy in mice and humans. To elucidate the mechanism of immune response induction, which is the basis for the efficacy and safety of TCI with sdMN, we examined the local reaction of the skin where sdMN was applied and the kinetics and differentiation status of immune cells in the draining lymph nodes (DLNs). We found that gene expression of the proinflammatory cytokine Il1b and the downstream transcription factor Irf7 was markedly upregulated in skin tissues after sdMN application. Moreover, activation of Langerhans cells and CD207- dermal dendritic cells, which are subsets of antigen-presenting cells (APCs) in the skin, and their migration to the DLNs were promoted. Furthermore, the activated APC subsets promoted CD4+ T cell and B cell differentiation and the formation of germinal centers, which are the sites of high-affinity antibody production. These phenomena associated with sdMN application may contribute to the efficient production of antigen-specific antibodies after TCI using sdMN. These findings provide essential information regarding immune response induction mechanisms for the development and improvement of TCI preparations.


Asunto(s)
Inmunización , Vacunación , Administración Cutánea , Animales , Formación de Anticuerpos , Sistemas de Liberación de Medicamentos/métodos , Ratones , Piel , Vacunación/métodos
5.
Nucleic Acids Res ; 36(5): 1464-71, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18203747

RESUMEN

Invasion of two PNA strands to double-stranded DNA is one of the most promising methods to recognize a predetermined site in double-stranded DNA (PNA = peptide nucleic acid). In order to facilitate this 'double-duplex invasion', a new type of PNA was prepared by using chiral PNA monomers in which a nucleobase was bound to the alpha-nitrogen of N-(2-aminoethyl)-d-lysine. These positively charged monomer units, introduced to defined positions in Nielsen's PNAs (poly[N-(2-aminoethyl)glycine] derivatives), promoted the invasion without impairing mismatch-recognizing activity. When pseudo-complementary nucleobases 2,6-diaminopurine and 2-thiouracil were bound to N-(2-aminoethyl)-d-lysine, the invasion successfully occurred even at highly G-C-rich regions [e.g. (G/C)7(A/T)3 and (G/C)8(A/T)2] which were otherwise hardly targeted. Thus, the scope of sequences available as the target site has been greatly expanded. In contrast with the promotion by the chiral PNA monomers derived from N-(2-aminoethyl)-d-lysine, their l-isomers hardly invaded, showing crucial importance of the d-chirality. The promotion of double-duplex invasion by the chiral (d) PNA monomer units was ascribed to both destabilization of PNA/PNA duplex and stabilization of PNA/DNA duplexes.


Asunto(s)
ADN/química , Ácidos Nucleicos de Péptidos/química , 2-Aminopurina/análogos & derivados , 2-Aminopurina/química , Secuencia Rica en At , Disparidad de Par Base , Secuencia de Bases , Secuencia Rica en GC , Electricidad Estática , Estereoisomerismo , Tiouracilo/química
6.
Planta ; 230(5): 899-915, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19669159

RESUMEN

Persimmon fruits accumulate a large amount of proanthocyanidin (PA) during development. Fruits of pollination-constant and non-astringent (PCNA) type mutants lose their ability to produce PA at an early stage of fruit development, while fruits of the normal (non-PCNA) type remain rich in PA until fully ripened. To understand the molecular mechanism for this difference, we isolated the genes involved in PA accumulation that are differentially expressed between PCNA and non-PCNA, and confirmed their correlation with PA content and composition. The expression of structural genes of the shikimate and flavonoid biosynthetic pathways and genes encoding transferases homologous to those involved in the accumulation of phenolic compounds were downregulated coincidentally only in the PCNA type. Analysis of PA composition using the phloroglucinol method suggested that the amounts of epigallocatechin and its 3-O-gallate form were remarkably low in the PCNA type. In the PCNA type, the genes encoding flavonoid 3'5' hydroxylase (F3'5'H) and anthocyanidin reductase (ANR) for epigallocatechin biosynthesis showed remarkable downregulation, despite the continuous expression level of their competitive genes, flavonoid 3' hydroxylation (F3'H) and leucoanthocyanidin reductase (LAR). We also confirmed that the relative expression levels of F3'5'H to F3'H, and ANR to LAR, were considerably higher, and the PA composition corresponded to the seasonal expression balances in both types. These results suggest that expressions of F3'5'H and ANR are important for PA accumulation in persimmon fruit. Lastly, we tested enzymatic activity of recombinant DkANR in vitro, which is thought to be an important enzyme for PA accumulation in persimmon fruits.


Asunto(s)
Diospyros/genética , Flavonoides/biosíntesis , Frutas/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proantocianidinas/metabolismo , Ácido Shikímico/metabolismo , Biopolímeros/química , Biopolímeros/metabolismo , Diospyros/enzimología , Diospyros/crecimiento & desarrollo , Frutas/enzimología , Frutas/crecimiento & desarrollo , Perfilación de la Expresión Génica , Redes y Vías Metabólicas/genética , Polinización/genética , Proantocianidinas/química , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
7.
Chem Commun (Camb) ; 53(24): 3426-3429, 2017 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-28239694

RESUMEN

A dihydroxy-substituted benzothienobenzothiophene, BTBT(OH)2, was synthesized, and its charge-transfer (CT) salt, ß-[BTBT(OH)2]2ClO4, was successfully obtained. Thanks to the introduced hydroxy groups, a hydrogen-bonded chain structure connecting the BTBT molecules and counter anions was formed in the CT salt, which effectively increases the dimensionality of the electronic structure and consequently leads to a stable metallic state.

8.
Chem Commun (Camb) ; 50(98): 15557-60, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25356679

RESUMEN

Solid-solid phase interconversion was observed in an organic conductor based on a hydrogen-bonded (H-bonded) TTF (tetrathiafulvalene) molecular unit, in which the π-stacked molecular arrangement and physical properties were dynamically changed with unexpected transformation of the H-bond unit between the planar and bent forms.

9.
Neurourol Urodyn ; 26(7): 1050-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17480029

RESUMEN

AIMS: The present study investigated the effects of ovariectomy and estrogen replacement on the release of acetylcholine (Ach) from cholinergic neurons as well as on the tetrodotoxin (TTX)-insensitive stretch-induced Ach release in isolated rat detrusor. In addition, the above effects on rat micturition characteristics were also studied. METHODS: Thirty female rats randomly received a sham operation, ovariectomy, or ovariectomy plus estrogen replacement. Using metabolic cages, micturition parameters were recorded. Then, in vitro functional experiments that included the measurements of nerve-mediated detrusor muscle contraction, Ach release from nerve fibres, and stretch-induced TTX-insensitive Ach release were performed. Ach release was measured using microdialysis and high-performance liquid chromatography. RESULTS: Ovariectomized rats showed a significant decrease in voided volume and significant increase in 24-hr frequency of voiding. Ovariectomy caused the significant increase in both TTX-insensitive basal Ach release and TTX-insensitive stretch-induced Ach release. On the other hand, ovariectomy caused a significant decrease in Ach release from nerve fibres, resulting in the decrease in the contractile responses of detrusor muscle to electrical nerve stimulation. Estrogen replacement restored these alterations induced by ovariectomy. CONCLUSIONS: Our findings showed that as a results of estrogen deficiency, Ach release from nerve fibres decreased, suggesting that this reduction of Ach released from cholinergic nerves may cause the decrease in detrusor contractility. Furthermore, this study also demonstrated that stretch-induced TTX-insensitive Ach release was increased by ovariectomy. This may be a contributing factor to the development of overactive bladder in elderly women.


Asunto(s)
Acetilcolina/metabolismo , Estradiol/farmacología , Terapia de Reemplazo de Estrógeno , Fibras Nerviosas/metabolismo , Ovariectomía , Vejiga Urinaria/metabolismo , Anestésicos/farmacología , Animales , Femenino , Microdiálisis , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/inervación , Músculo Liso/metabolismo , Fibras Nerviosas/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Tetrodotoxina/farmacología , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/inervación , Micción/efectos de los fármacos
10.
Nucleic Acids Symp Ser (Oxf) ; (50): 109-10, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17150841

RESUMEN

Chiral PNA monomers (PNA = peptide nucleic acid), in which nucleobases are attached to N-(aminoethyl)-D-lysine, were introduced to PNAs bearing pseudo-complementary nucleobases (2,6-diaminopurine and 2-thiouracil). When these highly cationic PNAs targeted double-stranded DNA, they invaded there much more efficiently than conventional pseudo-complementary PNAs composed of achiral PNA monomers. Although introduction of N-(aminoethyl)-D-lysine backbone was effective for promotion of strand invasion, L-isomer never promote it. Simple incorporation of lysine groups to the termini of PNA was also ineffective, indicating that introduction of positive charges into PNA backbone is important. Even highly G-C rich sequence, which conventional pseudo-complementary PNAs never invade, was successfully targeted based on this strategy.


Asunto(s)
ADN/química , Lisina/análogos & derivados , Ácidos Nucleicos de Péptidos/química , 2-Aminopurina/análogos & derivados , 2-Aminopurina/química , Ensayo de Cambio de Movilidad Electroforética , Secuencia Rica en GC , Isomerismo , Lisina/química , Electricidad Estática , Tiouracilo/química
11.
Nucleic Acids Symp Ser (Oxf) ; (48): 151-2, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17150523

RESUMEN

By using two oligonucleotides bearing a monophosphate group at the terminus and placing them at both edges of gap-site formed in substrate DNA, this site was preferentially and efficiently hydrolyzed by Ce(IV)/EDTA. In this study, site-selective hydrolysis of gap-site in long substrate DNA (274-mer) was investigated. When two monophosphate groups were placed to both edges of 5-base gap, predetermined site was selectively hydrolyzed by Ce(IV)/EDTA. Furthermore, desired recombinant DNA was prepared from this fragment and foreign DNA using T4 DNA ligase.


Asunto(s)
Cerio/metabolismo , ADN/metabolismo , Ácido Edético/metabolismo , Oligonucleótidos/química , Fosfatos/química , ADN Ligasas/metabolismo , Enzimas de Restricción del ADN/metabolismo , Electroforesis en Gel de Poliacrilamida , Hidrólisis
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