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1.
CEN Case Rep ; 12(3): 297-303, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36574196

RESUMEN

A 36-year-old female was pointed out to have liver enzyme elevation by routine health checkup. Subsequent contrast-enhanced CT scan identified gigantic uterine fibroids and retroperitoneal tumor. She was referred to the gynecologist at JA Toride Medical Center and planned to undergo a uterus enucleation and biopsy of the retroperitoneal tumor. The surgery was conducted without any troubles. After the surgery, the patient presented polyuria with urine volume 10-20 L a day and developed hypovolemic shock. Laboratory test revealed hypotonic urine and hypernatremia. Arginine vasopressin (AVP) loading test suggested shortage of endogenous vasopressin. Since the subcutaneous administration of AVP was not sufficient to control the urine volume, continuous intravenous infusion of AVP was initiated. After achieving hemodynamic stability, the treatment was switched to oral desmopressin. MRI finding indicated attenuation of high signal in posterior pituitary in T1 weighted image while neither enlargement of pituitary nor thickening of pituitary stalk was indicated by enhanced MRI. Hypertonic salt solution test indicated no responsive elevation of AVP, confirming the diagnosis of central diabetes insipidus (CDI). Her anterior pituitary function was preserved. Only anti-rabphilin-3A antibody was found positive in the serum of the patient, while other secondary causes for CDI were denied serologically and radiologically. Hence, lymphocytic infundibuloneurohypophysitis (LINH) was suspected as the final diagnosis. Hormonal replacement therapy by nasal desmopressin was continued and the patient managed to control her urine volume. In cases of CDI considered idiopathic with conventional examinations, anti-rabphilin-3A antibody may be a clue for determining the cause as LINH.


Asunto(s)
Diabetes Insípida Neurogénica , Diabetes Mellitus , Neoplasias Retroperitoneales , Femenino , Humanos , Adulto , Diabetes Insípida Neurogénica/diagnóstico , Diabetes Insípida Neurogénica/tratamiento farmacológico , Diabetes Insípida Neurogénica/etiología , Desamino Arginina Vasopresina/uso terapéutico , Neoplasias Retroperitoneales/complicaciones
2.
J Craniomaxillofac Surg ; 50(3): 225-229, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34930666

RESUMEN

The aim of this study was to investigate the clinical course of masticatory function recovery following arthrocentesis. Patients with a unilateral condylar head fracture who underwent arthrocentesis for therapeutic reasons were evaluated and compared with patients with a unilateral condylar head fracture who did not undergo arthrocentesis. At 3 months after treatment, the occlusal contact area and maximum bite force in patients with a fracture treated with arthrocentesis were greater than in those who did not receive arthrocentesis at the same time points, although the differences were not significant. Moreover, at 1 and 3 months following arthrocentesis, mean (±SD) occlusal contact area (1 month: 1.99 ± 0.55 mm2, p = 0.01; 3 months: 2.90 ± 1.36 mm2, p = 0.03) and maximum bite force (1 month: 82.45 ± 15.04 N, p = 0.01; 3 months: 101.11 ± 14.53 N, p = 0.01) on the fractured side in patients who underwent that treatment were significantly reduced when compared with those on the non-fractured side. The authors conclude that if the priority is to avoid open reduction and internal fixation, then the arthrocentesis approach might be a less invasive alternative, albeit with the price of a prolonged healing interval.


Asunto(s)
Cóndilo Mandibular , Fracturas Mandibulares , Artrocentesis , Fijación Interna de Fracturas , Humanos , Cóndilo Mandibular/cirugía , Fracturas Mandibulares/cirugía , Recuperación de la Función
3.
J Phys Chem B ; 125(29): 7997-8009, 2021 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-34259526

RESUMEN

Fluorescent proteins (FPs) have been widely used to visualize biological processes in living cells. It is essential to understand the underlying fluorescence mechanism to develop novel FPs and to interpret imaging data appropriately. Enhanced yellow fluorescent protein (eYFP) is one of the most typical FPs; however, several reports to date have been limited to individual discussion, which is insufficient to understand the full picture of the dynamics involved. In this study, we focused on the fluorescence resonance energy transfer (FRET) and dimerization behavior and performed picosecond time-resolved fluorescence measurements of eYFP and its A206K mutant, which does not form a dimer. The combination of the dissociation constant and the acid dissociation constant rationally explains the mechanism of ultrafast homo-FRET and ultrafast hetero-FRET. It is also shown that structural relaxation occurs in the dimer after excited-state proton transfer. The formation efficiencies and quaternary structures of dimers consisting of different protonation states are shown to be different. Furthermore, under high-concentration conditions, "slow" homo-FRET with tens of nanoseconds timescale occurs between monomers and dimers. The findings from this study will be applied to other fluorescent proteins such as Aequorea victoria green FP and its mutants and various red FPs with longer conjugation lengths.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Dimerización , Polarización de Fluorescencia , Proteínas Fluorescentes Verdes/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo
4.
Sci Rep ; 9(1): 11597, 2019 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-31406182

RESUMEN

Lignin is a phenylpropanoid polymer produced in the secondary cell walls of vascular plants. Although most eudicot and gymnosperm species generate lignins solely via polymerization of p-hydroxycinnamyl alcohols (monolignols), grasses additionally use a flavone, tricin, as a natural lignin monomer to generate tricin-incorporated lignin polymers in cell walls. We previously found that disruption of a rice 5-HYDROXYCONIFERALDEHYDE O-METHYLTRANSFERASE (OsCAldOMT1) reduced extractable tricin-type metabolites in rice vegetative tissues. This same enzyme has also been implicated in the biosynthesis of sinapyl alcohol, a monolignol that constitutes syringyl lignin polymer units. Here, we further demonstrate through in-depth cell wall structural analyses that OsCAldOMT1-deficient rice plants produce altered lignins largely depleted in both syringyl and tricin units. We also show that recombinant OsCAldOMT1 displayed comparable substrate specificities towards both 5-hydroxyconiferaldehyde and selgin intermediates in the monolignol and tricin biosynthetic pathways, respectively. These data establish OsCAldOMT1 as a bifunctional O-methyltransferase predominantly involved in the two parallel metabolic pathways both dedicated to the biosynthesis of tricin-lignins in rice cell walls. Given that cell wall digestibility was greatly enhanced in the OsCAldOMT1-deficient rice plants, genetic manipulation of CAldOMTs conserved in grasses may serve as a potent strategy to improve biorefinery applications of grass biomass.


Asunto(s)
Pared Celular/metabolismo , Flavonoides/biosíntesis , Lignina/biosíntesis , Metiltransferasas/metabolismo , Oryza/metabolismo , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
New Phytol ; 223(1): 204-219, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30883799

RESUMEN

In rice (Oryza sativa), OsF2H and OsFNSII direct flavanones to independent pathways that form soluble flavone C-glycosides and tricin-type metabolites (both soluble and lignin-bound), respectively. Production of soluble tricin metabolites requires CYP75B4 as a chrysoeriol 5'-hydroxylase. Meanwhile, the close homologue CYP75B3 is a canonical flavonoid 3'-hydroxylase (F3'H). However, their precise roles in the biosynthesis of soluble flavone C-glycosides and tricin-lignins in cell walls remain unknown. We examined CYP75B3 and CYP75B4 expression in vegetative tissues, analyzed extractable flavonoid profiles, cell wall structure and digestibility of their mutants, and investigated catalytic activities of CYP75B4 orthologues in grasses. CYP75B3 and CYP75B4 showed co-expression patterns with OsF2H and OsFNSII, respectively. CYP75B3 is the sole F3'H in flavone C-glycosides biosynthesis, whereas CYP75B4 alone provides sufficient 3',5'-hydroxylation for tricin-lignin deposition. CYP75B4 mutation results in production of apigenin-incorporated lignin and enhancement of cell wall digestibility. Moreover, tricin pathway-specific 3',5'-hydroxylation activities are conserved in sorghum CYP75B97 and switchgrass CYP75B11. CYP75B3 and CYP75B4 represent two different pathway-specific enzymes recruited together with OsF2H and OsFNSII, respectively. Interestingly, the OsF2H-CYP75B3 and OsFNSII-CYP75B4 pairs appear to be conserved in grasses. Finally, manipulation of tricin biosynthesis through CYP75B4 orthologues can be a promising strategy to improve digestibility of grass biomass for biofuel and biomaterial production.


Asunto(s)
Vías Biosintéticas , Flavonas/metabolismo , Flavonoides/metabolismo , Metaboloma , Oxigenasas de Función Mixta/metabolismo , Poaceae/metabolismo , Metabolismo de los Hidratos de Carbono , Pared Celular/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Flavonas/química , Flavonoides/química , Regulación de la Expresión Génica de las Plantas , Glicósidos/metabolismo , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Mutación/genética , Oryza/metabolismo , Panicum/metabolismo , Solubilidad , Sorghum/metabolismo
6.
Plant J ; 98(6): 975-987, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30773774

RESUMEN

Breeding approaches to enrich lignins in biomass could be beneficial to improving the biorefinery process because lignins increase biomass heating value and represent a potent source of valuable aromatic chemicals. However, despite the fact that grasses are promising lignocellulose feedstocks, limited information is yet available for molecular-breeding approaches to upregulate lignin biosynthesis in grass species. In this study, we generated lignin-enriched transgenic rice (Oryza sativa), a model grass species, via targeted mutagenesis of the transcriptional repressor OsMYB108 using CRISPR/Cas9-mediated genome editing. The OsMYB108-knockout rice mutants displayed increased expressions of lignin biosynthetic genes and enhanced lignin deposition in culm cell walls. Chemical and two-dimensional nuclear magnetic resonance (NMR) analyses revealed that the mutant cell walls were preferentially enriched in γ-p-coumaroylated and tricin lignin units, both of which are typical and unique components in grass lignins. NMR analysis also showed that the relative abundances of major lignin linkage types were altered in the OsMYB108 mutants.


Asunto(s)
Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Lignina/metabolismo , Oryza/genética , Propionatos/metabolismo , Factores de Transcripción/metabolismo , Biomasa , Sistemas CRISPR-Cas , Pared Celular/química , Pared Celular/metabolismo , Ácidos Cumáricos , Edición Génica , Redes Reguladoras de Genes , Lignina/química , Mutación con Pérdida de Función , Oryza/química , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Factores de Transcripción/genética , Regulación hacia Arriba
7.
Plant Physiol ; 179(4): 1796-1809, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30670602

RESUMEN

Striga species are parasitic weeds that seriously constrain the productivity of food staples, including cereals and legumes, in Sub-Saharan Africa and Asia. In eastern and central Africa, Striga spp. infest as much as 40 million hectares of smallholder farmland causing total crop failure during severe infestation. As the molecular mechanisms underlying resistance are yet to be elucidated, we undertook a comparative metabolome study using the Striga-resistant rice (Oryza sativa) cultivar 'Nipponbare' and the susceptible cultivar 'Koshihikari'. We found that a number of metabolites accumulated preferentially in the Striga-resistant cultivar upon Striga hermonthica infection. Most apparent was increased deposition of lignin, a phenylpropanoid polymer mainly composed of p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) aromatic units, around the site of interaction in Nipponbare. The increased deposition of lignin was accompanied by induction of the expression of corresponding enzyme-encoding genes in the phenylpropanoid pathway. In addition, perturbing normal lignin composition by knocking down or overexpressing the genes that regulate lignin composition, i.e. p-COUMARATE 3-HYDROXYLASE or FERULATE 5-HYDROXYLASE, enhanced susceptibility of Nipponbare to S hermonthica infection. These results demonstrate that enhanced lignin deposition and maintenance of the structural integrity of lignin polymers deposited at the infection site are crucial for postattachment resistance against S hermonthica.


Asunto(s)
Interacciones Huésped-Parásitos/genética , Lignina/química , Oryza/genética , Striga/fisiología , Lignina/genética , Oryza/parasitología , Enfermedades de las Plantas/genética , Raíces de Plantas/genética , Raíces de Plantas/parasitología
8.
Plant J ; 97(3): 543-554, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30375064

RESUMEN

The aromatic composition of lignin is an important trait that greatly affects the usability of lignocellulosic biomass. We previously identified a rice (Oryza sativa) gene encoding coniferaldehyde 5-hydroxylase (OsCAld5H1), which was effective in modulating syringyl (S)/guaiacyl (G) lignin composition ratio in rice, a model grass species. Previously characterized OsCAld5H1-knockdown rice lines, which were produced via an RNA-interference approach, showed augmented G lignin units yet contained considerable amounts of residual S lignin units. In this study, to further investigate the effect of suppression of OsCAld5H1 on rice lignin structure, we generated loss-of-function mutants of OsCAld5H1 using the CRISPR/Cas9-mediated genome editing system. Homozygous OsCAld5H1-knockout lines harboring anticipated frame-shift mutations in OsCAld5H1 were successfully obtained. A series of wet-chemical and two-dimensional NMR analyses on cell walls demonstrated that although lignins in the mutant were predictably enriched in G units all the tested mutant lines produced considerable numbers of S units. Intriguingly, lignin γ-p-coumaroylation analysis by the derivatization followed by reductive cleavage method revealed that enrichment of G units in lignins of the mutants was limited to the non-γ-p-coumaroylated units, whereas grass-specific γ-p-coumaroylated lignin units were almost unaffected. Gene expression analysis indicated that no homologous genes of OsCAld5H1 were overexpressed in the mutants. These data suggested that CAld5H is mainly involved in the production of non-γ-p-coumaroylated S lignin units, common in both eudicots and grasses, but not in the production of grass-specific γ-p-coumaroylated S units in rice.


Asunto(s)
Acroleína/análogos & derivados , Lignina/metabolismo , Oxigenasas de Función Mixta/metabolismo , Oryza/genética , Acroleína/metabolismo , Biomasa , Sistemas CRISPR-Cas , Pared Celular/metabolismo , Ácidos Cumáricos , Mutación con Pérdida de Función , Oxigenasas de Función Mixta/genética , Oryza/enzimología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Propionatos/metabolismo
9.
Plant J ; 2018 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-29890017

RESUMEN

p-Coumaroyl ester 3-hydroxylase (C3'H) is a key enzyme involved in the biosynthesis of lignin, a phenylpropanoid polymer that is the major constituent of secondary cell walls in vascular plants. Although the crucial role of C3'H in lignification and its manipulation to upgrade lignocellulose have been investigated in eudicots, limited information is available in monocotyledonous grass species, despite their potential as biomass feedstocks. Here we address the pronounced impacts of C3'H deficiency on the structure and properties of grass cell walls. C3'H-knockdown lines generated via RNA interference (RNAi)-mediated gene silencing, with about 0.5% of the residual expression levels, reached maturity and set seeds. In contrast, C3'H-knockout rice mutants generated via CRISPR/Cas9-mediated mutagenesis were severely dwarfed and sterile. Cell wall analysis of the mature C3'H-knockdown RNAi lines revealed that their lignins were largely enriched in p-hydroxyphenyl (H) units while being substantially reduced in the normally dominant guaiacyl (G) and syringyl (S) units. Interestingly, however, the enrichment of H units was limited to within the non-acylated lignin units, with grass-specific γ-p-coumaroylated lignin units remaining apparently unchanged. Suppression of C3'H also resulted in relative augmentation in tricin residues in lignin as well as a substantial reduction in wall cross-linking ferulates. Collectively, our data demonstrate that C3'H expression is an important determinant not only of lignin content and composition but also of the degree of cell wall cross-linking. We also demonstrated that C3'H-suppressed rice displays enhanced biomass saccharification.

10.
New Phytol ; 218(2): 710-723, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29498051

RESUMEN

Parasitic plants in the family Orobanchaceae are destructive weeds of agriculture worldwide. The haustorium, an essential parasitic organ used by these plants to penetrate host tissues, is induced by host-derived phenolic compounds called haustorium-inducing factors (HIFs). The origin of HIFs remains unknown, although the structures of lignin monomers resemble that of HIFs. Lignin is a natural phenylpropanoid polymer, commonly found in secondary cell walls of vascular plants. We therefore investigated the possibility that HIFs are derived from host lignin. Various lignin-related phenolics, quinones and lignin polymers, together with nonhost and host plants that have different lignin compositions, were tested for their haustorium-inducing activity in two Orobanchaceae species, a facultative parasite, Phtheirospermum japonicum, and an obligate parasite, Striga hermonthica. Lignin-related compounds induced haustoria in P. japonicum and S. hermonthica with different specificities. High concentrations of lignin polymers induced haustorium formation. Treatment with laccase, a lignin degradation enzyme, promoted haustorium formation at low concentrations. The distinct lignin compositions of the host and nonhost plants affected haustorium induction, correlating with the response of the different parasitic plants to specific types of lignin-related compounds. Our study provides valuable insights into the important roles of lignin biosynthesis and degradation in the production of HIFs.


Asunto(s)
Interacciones Huésped-Parásitos , Lignina/metabolismo , Orobanchaceae/anatomía & histología , Striga/anatomía & histología , Antocianinas/metabolismo , Arabidopsis/parasitología , Vías Biosintéticas , Oryza/parasitología , Plantas Modificadas Genéticamente , Quinonas/metabolismo
11.
J Craniomaxillofac Surg ; 45(9): 1458-1463, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28689686

RESUMEN

The CryoSeal® FS System has been recently introduced as an automated device for the production of complete fibrin glue from autologous plasma, rather than from pool allogenic or cattle blood, to prevent viral infection and allergic reaction. We evaluated the effectiveness of complete autologous fibrin glue and polyglycolic acid (PGA) sheet wound coverings in mucosa defect oral surgery. Postoperative pain, scar contracture, ingestion, tongue dyskinesia, and postoperative bleeding were evaluated in 12 patients who underwent oral (including the tongue) mucosa excision, and received a PGA sheet and an autologous fibrin glue covering. They were compared with 12 patients who received a PGA sheet and commercial allogenic fibrin glue. All cases in the complete autologous fibrin glue group demonstrated good wound healing without complications such as local infection or incomplete cure. All evaluated clinical measures in this group were similar or superior to the commercial allogenic fibrin glue group. Coagulation and adhesion quality achieved with this method was comparable to that with a PGA sheet and commercial fibrin glue. Covering oral surgery wounds with complete autologous fibrin glue produced by an automated device was convenient, safe, and reduced the risk of viral infection and allergic reaction associated with conventional techniques.


Asunto(s)
Vendajes , Adhesivo de Tejido de Fibrina , Enfermedades de la Boca/cirugía , Boca/cirugía , Ácido Poliglicólico , Adhesivos Tisulares , Cicatrización de Heridas , Autoinjertos , Apósitos Biológicos , Humanos , Mucosa Bucal/cirugía , Neoplasias de la Boca/cirugía , Procedimientos Quirúrgicos Orales , Lesiones Precancerosas/cirugía , Infección de la Herida Quirúrgica/prevención & control , Lengua/cirugía
12.
Int J Mol Sci ; 18(6)2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28561797

RESUMEN

While metallic biomaterials have led to an improvement in the quality of life, metal allergies, especially to palladium (Pd), has caused a recent increase in allergic patients. Metal allergy is known to be a T cell-mediated delayed-type hypersensitivity (DTH); however, the pathogenic T cell subsets and the specific T cell receptor (TCR) have not been identified. Therefore, we attempted to identify the pathogenic T cells responsible for Pd allergy. We found that activating CD8⁺ T cells significantly increased and that the TRAV (TCRα variable) 7-2*02 chain skewed in Pd allergic mice. Furthermore, adoptive transfer experiments revealed that in vitro-cultured Pd-stimulated antigen presenting cells (APCs) function as memory APCs with recipient mice developing Pd allergy and that the frequency of TRAV7-2*02 increases the same as conventional Pd allergic mice. In contrast, neither proliferation of CD8⁺ T cells nor increasing of TRAV7-2*02 was observed in major histocompatibility complex I (MHC I)-deficient Pd-APCs transferred to mice. Taken together, we revealed that TRAV7-2*02-expressing CD8⁺ T cells are the pathogenic T cells for the development of Pd allergy. We also identified the CDR3 consensus motif of pathogenic TCRs as CAAXSGSWQLIF in TRAV7-2*02/TRAJ (TCRα junction)22*01 positive cells. These results suggest that the specific TCRs represent novel targets for the development of diagnostics and treatments for metal allergy.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Hipersensibilidad/inmunología , Paladio/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Traslado Adoptivo , Animales , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/trasplante , Linfocitos T CD8-positivos/metabolismo , Células Cultivadas , Hipersensibilidad/genética , Hipersensibilidad/metabolismo , Interferón gamma/inmunología , Interferón gamma/metabolismo , Activación de Linfocitos/inmunología , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo
13.
Planta ; 246(2): 337-349, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28421330

RESUMEN

MAIN CONCLUSION: Regulation of a gene encoding coniferaldehyde 5-hydroxylase leads to substantial alterations in lignin structure in rice cell walls, identifying a promising genetic engineering target for improving grass biomass utilization. The aromatic composition of lignin greatly affects utilization characteristics of lignocellulosic biomass and, therefore, has been one of the primary targets of cell wall engineering studies. Limited information is, however, available regarding lignin modifications in monocotyledonous grasses, despite the fact that grass lignocelluloses have a great potential for feedstocks of biofuel production and various biorefinery applications. Here, we report that manipulation of a gene encoding coniferaldehyde 5-hydroxylase (CAld5H, or ferulate 5-hydroxylase, F5H) leads to substantial alterations in syringyl (S)/guaiacyl (G) lignin aromatic composition in rice (Oryza sativa), a major model grass and commercially important crop. Among three CAld5H genes identified in rice, OsCAld5H1 (CYP84A5) appeared to be predominantly expressed in lignin-producing rice vegetative tissues. Down-regulation of OsCAld5H1 produced altered lignins largely enriched in G units, whereas up-regulation of OsCAld5H1 resulted in lignins enriched in S units, as revealed by a series of wet-chemical and NMR structural analyses. Our data collectively demonstrate that OsCAld5H1 expression is a major factor controlling S/G lignin composition in rice cell walls. Given that S/G lignin composition affects various biomass properties, we contemplate that manipulation of CAld5H gene expression represents a promising strategy to upgrade grass biomass for biorefinery applications.


Asunto(s)
Carboxiliasas/metabolismo , Lignina/metabolismo , Oryza/enzimología , Acroleína/análogos & derivados , Acroleína/química , Acroleína/metabolismo , Biocombustibles , Biomasa , Vías Biosintéticas , Carboxiliasas/genética , Pared Celular/metabolismo , Regulación hacia Abajo , Ingeniería Genética , Lignina/química , Oryza/citología , Oryza/genética , Oryza/crecimiento & desarrollo , Filogenia , Hojas de la Planta/anatomía & histología , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regulación hacia Arriba
14.
Plant Physiol ; 174(2): 972-985, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28385728

RESUMEN

Lignin, a ubiquitous phenylpropanoid polymer in vascular plant cell walls, is derived primarily from oxidative couplings of monolignols (p-hydroxycinnamyl alcohols). It was discovered recently that a wide range of grasses, including cereals, utilize a member of the flavonoids, tricin (3',5'-dimethoxyflavone), as a natural comonomer with monolignols for cell wall lignification. Previously, we established that cytochrome P450 93G1 is a flavone synthase II (OsFNSII) indispensable for the biosynthesis of soluble tricin-derived metabolites in rice (Oryza sativa). Here, our tricin-deficient fnsII mutant was analyzed further with an emphasis on its cell wall structure and properties. The mutant is similar in growth to wild-type control plants with normal vascular morphology. Chemical and nuclear magnetic resonance structural analyses demonstrated that the mutant lignin is completely devoid of tricin, indicating that FNSII activity is essential for the deposition of tricin-bound lignin in rice cell walls. The mutant also showed substantially reduced lignin content with decreased syringyl/guaiacyl lignin unit composition. Interestingly, the loss of tricin in the mutant lignin appears to be partially compensated by incorporating naringenin, which is a preferred substrate of OsFNSII. The fnsII mutant was further revealed to have enhanced enzymatic saccharification efficiency, suggesting that the cell wall recalcitrance of grass biomass may be reduced through the manipulation of the flavonoid monomer supply for lignification.


Asunto(s)
Biomasa , Lignina/metabolismo , Oxigenasas de Función Mixta/metabolismo , Oryza/enzimología , Vías Biosintéticas/genética , Pared Celular/metabolismo , Fertilidad/genética , Regulación de la Expresión Génica de las Plantas , Técnicas de Inactivación de Genes , Genes de Plantas , Espectroscopía de Resonancia Magnética , Mutación/genética , Oryza/genética , Fenotipo
15.
Int Immunopharmacol ; 35: 70-76, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27035718

RESUMEN

Because of its corrosion resistance palladium (Pd) has been widely used in many consumer products ranging from fashion accessories to dental materials. Recently, however, an increase in Pd allergy cases has been reported. Metal allergy is categorized as a Type IV allergy, which is characterized as a delayed-type hypersensitivity reaction in which T cells are known to play an important role; however, the precise mechanism of their action remains unclear. Here we defined the relationship between histamine and the Pd allergic reaction specifically with respect to T cell responses. To verify the effects of histamine on T cells, we examined whether there is a change in IFN-γ production following stimulation of histamine or the antihistamine, olopatadine hydrochloride (OLP), in vitro. In addition, we assessed whether OLP administration affected the degree of footpad swelling or IFN-γ production during the Pd allergy response in mice. We found that histamine stimulation increased IFN-γ production in T cells, specifically enhancing IFN-γ production in CD8(+) T cells compared with CD4(+) T cells. Interestingly, OLP suppressed the production of IFN-γ in CD8(+) T cells, and this compound inhibited footpad swelling and IFN-γ production in mice with Pd allergy. These results suggest that histamine promotes the Type IV allergic reaction and thus, the histamine 1 receptor (H1R) might be useful therapeutic target for treatment of metal allergy.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Hipersensibilidad Tardía/tratamiento farmacológico , Clorhidrato de Olopatadina/uso terapéutico , Alérgenos/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Células Cultivadas , Histamina/inmunología , Humanos , Hipersensibilidad Tardía/inmunología , Interferón gamma/metabolismo , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Paladio/inmunología , Receptores Histamínicos H1/metabolismo
16.
Liver Int ; 35(3): 925-35, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25627311

RESUMEN

BACKGROUND & AIMS: Fetuin-A (α2HS-glycoprotein), a liver secretory glycoprotein, is known as a transforming growth factor (TGF)-ß1 signalling inhibitor. Serum fetuin-A concentration is associated with nonalcoholic fatty liver disease (NAFLD) and cardiovascular disease. However, the usefulness of serum fetuin-A as a predictive fibrosis biomarker in NAFLD patients remains unclear. In this study, we investigated the relationship between circulating fetuin-A levels and fibrosis-related markers [platelet count, NAFLD fibrosis score and carotid intima media thickness (IMT)] in subjects with NAFLD. METHODS: A total of 295 subjects (male, 164; female, 131) who received medical health check-ups were enrolled in this study. NAFLD was diagnosed using abdominal ultrasonography. Serum fetuin-A was measured by ELISA. IMT was assessed using a high-resolution ultrasound scanner. Using recombinant human fetuin-A, we investigated the effects of fetuin-A on hepatic stellate cells, which play a pivotal role in the process of hepatic fibrosis. RESULTS: Serum fetuin-A concentration was significantly correlated with platelet count (R = 0.19, P < 0.01), NAFLD fibrosis score (R = -0.25, P < 0.01) and mean IMT (R = -0.22, P < 0.01). Multivariate analyses revealed that the fetuin-A concentration is a significant and independent determinant of platelet count, NAFLD fibrosis score and mean IMT. Recombinant fetuin-A suppressed TGF-ß1 signalling and fibrosis-related gene expression and increased the expression of TGF-ß1 pseudoreceptor bone morphogenic protein and activin membrane-bound inhibitor (BAMBI). CONCLUSIONS: Serum fetuin-A level is associated with liver/vessel fibrosis-related markers in NAFLD patients. Circulating fetuin-A could be a useful serum biomarker for predicting liver and vascular fibrosis progression in NAFLD patients.


Asunto(s)
Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/sangre , alfa-2-Glicoproteína-HS/metabolismo , Anciano , Biomarcadores/sangre , Grosor Intima-Media Carotídeo , Línea Celular , Femenino , Fibrosis , Células Estrelladas Hepáticas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/patología , Recuento de Plaquetas , Factor de Crecimiento Transformador beta1
17.
Clin Chem Lab Med ; 53(1): 95-102, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25060348

RESUMEN

BACKGROUND: Fucosylation is one of the most important glycosylation events involved in cancer and inflammation. We previously developed a lectin antibody ELISA kit to measure fucosylated haptoglobin (Fuc-Hpt), which we identified as a novel cancer biomarker. In this study, we investigated Fuc-Hpt as a biomarker in chronic liver diseases, especially in hepatocellular carcinoma (HCC). METHODS: We measured serum Fuc-Hpt levels using our ELISA kit in 318 patients with chronic liver diseases, including 145 chronic hepatitis (CH) patients, 81 liver cirrhosis (LC) patients, and 92 HCC patients. During a long-term follow-up period of 7 years (1996-2003), Fuc-Hpt levels were measured at three different time points in 19 HCC patients. Serum Fuc-Hpt levels were also examined with a short-term follow-up period of 3 years (2009-2012) in 13 HCC patients. RESULTS: Fuc-Hpt levels increased with liver disease progression. Patients with LC and HCC showed significantly increased Fuc-Hpt levels in comparison to CH patients or healthy volunteers. Fuc-Hpt levels tended to be higher in HCC patients than in LC patients. Fuc-Hpt was better than α-fetoprotein (AFP) and AFP-L3 for predicting HCC [diagnosed by computed tomography (CT) or ultrasound] in LC patients with long-term follow-up. More than 80% of LC patients with long-term follow-up showed increased Fuc-Hpt during hepatocarcinogenesis, and 38% of early-stage HCC patients with short-term follow-up showed a gradual increase in Fuc-Hpt before imaging diagnosis. CONCLUSIONS: These results suggest that Fuc-Hpt is a novel and potentially useful biomarker for predicting liver disease progression and HCC development.


Asunto(s)
Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/sangre , Fucosa/metabolismo , Haptoglobinas/metabolismo , Neoplasias Hepáticas/sangre , Progresión de la Enfermedad , Detección Precoz del Cáncer , Humanos , Neoplasias Hepáticas/diagnóstico
18.
PLoS One ; 9(2): e86810, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24533050

RESUMEN

Nickel, cobalt, and chromium are well known to be causal agents of allergic contact dermatitis. Palladium (Pd) can also cause allergic disease and exposure results from wide use of this metal in dental restorations and jewelry. Metal allergy is categorized as a delayed-type hypersensitivity, and metal-responsive T cell clones have been isolated from allergic patients. However, compared to nickel, little is known about the pathology of allergic disease mediated by Pd, and pathogenic T cells are poorly understood. To identify the pathogenic T cells that are responsible for onset of Pd allergy, we enriched metal-responsive lymphocytes by sequential adoptive transfer of involved lymph node cells. Here we show that sequential adoptive transfer gradually increased the incidence and the intensity of Pd allergy, and CD8⁺ T cells are responsible for the disease as CD8⁺ T cell-depleted mice and ß2-microglobulin-deficient mice did not develop Pd allergy. In addition, we found that draining lymph node cells skewed toward CD8⁺ T cells in response to Pd challenge in 8th adoptive transferred recipient mice. The CD8⁺ T cells expressed NKG2D, a costimulatory molecule involved in the production of IFN-γ. NKG2D ligand was also induced in Pd-injected tissues. Furthermore, both NKG2D ligand-transgenic mice, where NKG2D is downmodulated, and IFN-γ-deficient mice showed impaired Pd allergy. Taken together, these results indicate that IFN-γ-producing NKG2D⁺ CD8⁺ T cells are responsible for Pd allergy and suggest that NKG2D is a potential therapeutic target for treatment of metal allergy.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Dermatitis por Contacto/inmunología , Interferón gamma/metabolismo , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Paladio/inmunología , Traslado Adoptivo , Animales , Ligandos , Metales/inmunología , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Desnudos , Ratones Transgénicos , Microglobulina beta-2/metabolismo
19.
PLoS One ; 8(6): e66328, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23805214

RESUMEN

UNLABELLED: Nonalcoholic fatty liver disease (NAFLD) is a growing medical problem around the world. NAFLD patients with nonalcoholic steatohepatitis (NASH) can develop cirrhosis and hepatocellular carcinoma. The ability to distinguish NASH from simple steatosis would be of great clinical significance. Ballooning hepatocytes are characteristic of typical pathological NASH; here, the polarized secretion of proteins is disrupted due to destruction of the cytoskeleton. We previously reported that fucosylated glycoproteins are secreted into bile, but not into sera in normal liver. Therefore, we hypothesized that the fucosylation-based sorting machinery would be disrupted in ballooning hepatocytes, and serum fucosylated glycoproteins would increase in NASH patients. To confirm our hypothesis, we evaluated serum fucosylated haptoglobin (Fuc-Hpt) levels in biopsy-proven NAFLD patients (n = 126) using a lectin-antibody ELISA kit. Fuc-Hpt levels were significantly increased in NASH patients compared with non-NASH (NAFLD patients without NASH) patients. Interestingly, Fuc-Hpt levels showed a significant stepwise increase with increasing hepatocyte ballooning scores. Multiple logistic regression analysis showed that Fuc-Hpt levels were independent and significant determinants of the presence of ballooning hepatocytes. Moreover, Fuc-Hpt levels were useful in monitoring liver fibrosis staging. Next, to investigate the significance of serum Fuc-Hpt in a larger population, we measured Fuc-Hpt levels in ultrasound-diagnosed NAFLD subjects (n = 870) who received a medical health checkup. To evaluate NAFLD disease severity, we used the FIB-4 index (based on age, serum AST and ALT levels, and platelet counts). Fuc-Hpt levels increased stepwise with increasing FIB-4 index. CONCLUSION: Measurement of serum Fuc-Hpt levels can distinguish NASH from non-NASH patients, and predict the presence of ballooning hepatocytes in NAFLD patients with sufficient accuracy. These results support the potential usefulness of measuring Fuc-Hpt levels in clinical practice.


Asunto(s)
Haptoglobinas/metabolismo , Hepatocitos/metabolismo , Enfermedad del Hígado Graso no Alcohólico , Adulto , Factores de Edad , Anciano , Biomarcadores/sangre , Femenino , Hepatocitos/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/patología
20.
Biopharm Drug Dispos ; 33(4): 195-206, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22447511

RESUMEN

The in vitro and in vivo inhibition of cytochrome P450 (CYP) 3A with mechanism-based inhibition (MBI) by macrolides was investigated using dexamethasone-treated female rats (DEX-female rats). In the in vitro CYP inhibition studies using erythromycin (ERM) and clarithromycin (CAM), similar inhibition responses were observed between human and DEX-female rat liver microsomes, however, there were fewer effects in intact male rats. The ex vivo study showed that midazolam (MDZ) metabolism in liver microsomes of DEX-female rats was reduced by ERM administration and the inhibitory effect was increased with increasing ERM doses, indicating that metabolite intermediate complex formation caused irreversible inhibition of CYP3A activity in DEX-female rats as well as in humans. In the in vivo studies, ERM and CAM significantly increased the area under the plasma concentration-time curve of MDZ and decreased the total clearance in DEX-female rats. It was concluded that the DDIs via MBI of CYP3A following macrolide administration in humans could be reproduced in female rats, suggesting that DEX-female rats can serve as an in vivo model for assessing this DDI in humans.


Asunto(s)
Claritromicina/farmacología , Inhibidores del Citocromo P-450 CYP3A , Eritromicina/farmacología , Midazolam/metabolismo , Animales , Área Bajo la Curva , Citocromo P-450 CYP3A/metabolismo , Dexametasona/administración & dosificación , Dexametasona/farmacología , Interacciones Farmacológicas , Femenino , Humanos , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Modelos Biológicos , Ratas , Factores Sexuales , Especificidad de la Especie
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