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1.
Plant Biol (Stuttg) ; 23 Suppl 1: 210-220, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32492761

RESUMEN

The tomato accession LA1996, which carries a dominant allele of anthocyanin fruit (Aft) locus, accumulates anthocyanins in the epidermis of fruits when exposed to sunlight. The involvement of blue, UV-A, UV-B and a combination of these wavelengths on anthocyanin accumulation and the molecular mechanism of their regulation was investigated in LA1996. The most effective treatment for inducing anthocyanin biosynthesis in Aft fruits was co-irradiation with blue and UV-B (blue + UV-B) light. Finding the correlated genes is an important approach towards understanding their molecular mechanisms. In the present study, the nitrate reductase (NR) gene SlNIA was isolated using RNA-seq profiling of Aft fruits given different light treatments. The functions of NR-mediated anthocyanin induction by blue + UV-B were confirmed using a series of chemical treatments, followed by assessment of NR activity and nitric oxide (NO) detection. The expression of NR was highly induced by blue + UV-B, and this specificity was also confirmed with the enzyme activity of NR and the NO concentration. The NR inhibitors, which reduce NO generation, the expression levels of anthocyanin related genes and decreased anthocyanin accumulation in LA1996. Our results suggest that NR plays a key role in blue + UV-B-mediated anthocyanin accumulation in LA1996 fruits.


Asunto(s)
Antocianinas , Nitrato-Reductasa/metabolismo , Solanum lycopersicum , Frutas/enzimología , Frutas/genética , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/efectos de la radiación , Nitrato-Reductasa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rayos Ultravioleta
2.
Transplant Proc ; 50(4): 1129-1131, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29731079

RESUMEN

INTRODUCTION: Donor safety is one of the most important factors in living-donor liver transplantation. Duodenal ulcer (DU) is a common postoperative complication. Here we aimed to reveal the risk factors associated with postoperative DU in the donors. METHODS: Between April 2007 and March 2017, 318 cases underwent donor hepatectomy for liver transplantation at Kumamoto University Hospital. We classified the donors into two groups: a DU group and a non-DU group. DU was defined as mucosal break with unequivocal depth requiring an endoscopic procedure. The characteristics and clinical factors of the donors were retrospectively analyzed. RESULTS: Postoperative DU occurred in 17 donors during the study period. The mean interval after donor hepatectomy to occurrence of DU was 124.8 ± 185.4 days. The two groups were comparable in terms of age at time of the donor hepatectomy (P = .45). The male-to-female ratio (P = .03) was significantly different between the two groups and left-side hepatectomy was performed more often in the DU group (P = .003). Multivariable logistic regression revealed that left-side hepatectomy was independently associated with postoperative DU in the donors. CONCLUSIONS: These findings indicated that left-side hepatectomy is a risk factor for postoperative DU in the donors.


Asunto(s)
Úlcera Duodenal/etiología , Hepatectomía/métodos , Trasplante de Hígado/efectos adversos , Donadores Vivos , Complicaciones Posoperatorias/etiología , Adulto , Femenino , Hepatectomía/efectos adversos , Humanos , Hígado/cirugía , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Recolección de Tejidos y Órganos/efectos adversos , Recolección de Tejidos y Órganos/métodos
3.
World J Surg Oncol ; 15(1): 179, 2017 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-28962578

RESUMEN

BACKGROUND: Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA) is a promising real-time navigation method in the surgical resection of malignant gliomas. In order to determine whether this method is applicable to metastatic brain tumors, we evaluated the usefulness of intraoperative fluorescence patterns and histopathological features in patients with metastatic brain tumors. METHODS: We retrospectively reviewed the cases of 16 patients with metastatic brain tumors who underwent intraoperative 5-ALA fluorescence-guided resection. Patients were given 20 mg/kg of 5-ALA orally 2 h prior to the surgery. High-powered excitation illumination and a low-pass filter (420, 450, or 500 nm) were used to visualize the fluorescence of protoporphyrin IX (PpIX), the 5-ALA metabolite. We evaluated the relationships between the fluorescence and histopathological findings in both tumoral and peritumoral brain tissue. RESULTS: Tumoral PpIX fluorescence was seen in only 5 patients (31%); in the remaining 11 patients (69%), there was no fluorescence in the tumor bulk itself. In 14 patients (86%), vague fluorescence was seen in peritumoral brain tissue, at a thickness of 2-6 mm. The histopathological examination found cancer cell invasion of adjacent brain tissue in 75% of patients (12/16), at a mean ± SD depth of 1.4 ± 1.0 mm (range 0.2-3.4 mm) from the microscopic border of the tumor. There was a moderate correlation between vague fluorescence in adjacent brain tissue and the depth of cancer cell invasion (P = 0.004). CONCLUSION: Peritumoral fluorescence may be a good intraoperative indicator of tumor extent, preceding more complete microscopic gross total resection. TRIAL REGISTRATION: Institutional Review Board of Osaka Medical College No. 42, registered February 17, 1998, and No. 300, registered April 1, 2008. They were retrospectively registered.


Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Neoplasias Encefálicas/cirugía , Procedimientos Neuroquirúrgicos/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Protoporfirinas/química , Cirugía Asistida por Computador/métodos , Adulto , Anciano , Ácido Aminolevulínico/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/cirugía , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Femenino , Fluorescencia , Humanos , Cuidados Intraoperatorios/métodos , Imagen por Resonancia Magnética , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Procedimientos Neuroquirúrgicos/instrumentación , Estudios Retrospectivos , Cirugía Asistida por Computador/instrumentación
4.
Rev Sci Instrum ; 88(5): 056101, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28571445

RESUMEN

The real-time detection of epithermal neutrons forms an important aspect of boron neutron capture therapy. In this context, we developed an epithermal neutron detector based on the combination of a small Eu:LiCaAlF6 scintillator and a quartz fiber in order to fulfill the irradiation-field requirements for boron neutron capture therapy. The irradiation test is performed with the use of a reactor-based neutron source. The thermal and epithermal neutron sensitivities of our epithermal neutron detector are estimated to be 9.52 × 10-8 ± 1.59 × 10-8 cm2 and 1.20 × 10-6 cm2 ± 8.96 × 10-9 cm2, respectively. We also subject the developed epithermal neutron detector to actual irradiation fields, and we confirm that the epithermal neutron flux can be measured in realtime.

5.
Nano Lett ; 17(5): 2865-2870, 2017 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-28350468

RESUMEN

Constructing quantum devices comprises various challenging tasks, especially when concerning their nanoscale geometry. For quantum color centers, the traditional approach is to fabricate the device structure after the nondeterministic placement of the centers. Reversing this approach, we present the controlled generation of quantum centers in silicon carbide (SiC) by focused proton beam in a noncomplex manner without need for pre- or postirradiation treatment. The generation depth and resolution can be predicted by matching the proton energy to the material's stopping power, and the amount of quantum centers at one specific sample volume is tunable from ensembles of millions to discernible single photon emitters. We identify the generated centers as silicon vacancies through their characteristic magnetic resonance signatures and demonstrate that they possess a long spin-echo coherence time of 42 ± 20 µs at room temperature. Our approach hence enables the fabrication of quantum hybrid nanodevices based on SiC platform, where spin centers are integrated into p-i-n diodes, photonic cavities, and mechanical resonators.

6.
Int J Oral Maxillofac Surg ; 46(2): 267-273, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27856151

RESUMEN

The purpose of this study was to retrospectively investigate the outcomes of Brånemark System Mk III TiUnite/Groovy implants placed in patients at Kobe University Hospital. Various risk factors for implant failure, including mechanical coupling, were investigated by univariate and multivariate analysis. The predictive variables investigated included age, sex, smoking habit, general health, history of radiation therapy, application of a dentomaxillary prosthesis, type of prosthesis, use of alveolar bone augmentation, site of implant insertion, mechanical coupling between implants, and the length and diameter of the implants. Of the 907 implants investigated, only 23 were unsuccessful; the overall survival rate was 96.7%. Increased age, radiation therapy, application of a removable prosthesis or dentomaxillary prosthesis, lack of mechanical coupling between implants, and shorter implants (≤8.5mm) were significant risk factors for implant failure according to univariate analysis (P<0.05). Multivariate analysis identified a significant association (P<0.05) between dental implant failure and a lack of mechanical coupling between implants (odds ratio 6.88) and shorter implants (≤8.5mm) (odds ratio 3.43). The findings of this study demonstrated multivariate relationships between various risk factors and dental implant failure.


Asunto(s)
Implantación Dental Endoósea/efectos adversos , Implantes Dentales/efectos adversos , Fracaso de la Restauración Dental , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales
7.
Analyst ; 140(21): 7202-8, 2015 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-26365298

RESUMEN

A novel screening system, using affinity imaging mass spectrometry (AIMS), has been developed to identify protein aggregates or organ structures in unfixed human tissue. Frozen tissue sections are positioned on small (millimetre-scale) stainless steel chips and incubated with an extensive library of small molecules. Candidate molecules showing specific affinity for the tissue section are identified by imaging mass spectrometry (IMS). As an example application, we screened over a thousand compounds against Alzheimer's disease (AD) brain tissue and identified several compounds with high affinity for AD brain sections containing tau deposits compared to age-matched controls. It should also be possible to use AIMS to isolate chemical compounds with affinity for tissue structures or components that have been extensively modified by events such as oxidation, phosphorylation, acetylation, aggregation, racemization or truncation, for example, due to aging. It may also be applicable to biomarker screening programs.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Encéfalo/metabolismo , Espectrometría de Masas/métodos , Tecnología Farmacéutica/métodos , Péptidos beta-Amiloides/química , Anticuerpos/química , Biomarcadores/química , Encéfalo/efectos de los fármacos , Criopreservación , Diseño de Equipo , Lóbulo Frontal/metabolismo , Humanos , Iones , Oxígeno/química , Fosforilación , Robótica , Estereoisomerismo , Proteínas tau/química
8.
Cell Death Dis ; 3: e353, 2012 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-22825471

RESUMEN

Exploiting protein homeostasis is a new therapeutic approach in cancer. Nelfinavir (NFV) is an HIV protease inhibitor that induces endoplasmic reticulum (ER) stress in cancer cells. Under conditions of ER stress, misfolded proteins are transported from the ER back to the cytosol for subsequent degradation by the ubiquitin-proteasome system. Bortezomib (BZ) is a proteasome inhibitor and interferes with degradation of misfolded proteins. Here, we show that NFV and BZ enhance proteotoxicity in non-small cell lung cancer (NSCLC) and multiple myeloma (MM) cells. The combination synergistically inhibited cell proliferation and induced cell death. Activating transcription factor (ATF)3 and CCAAT-enhancer binding protein homologous protein (CHOP), markers of ER stress, were rapidly increased, and their siRNA-mediated knockdown inhibited cell death. Knockdown of double-stranded RNA activated protein kinase-like ER kinase, a signal transducer in ER stress, significantly decreased apoptosis. Pretreatment with the protein synthesis inhibitor, cycloheximide, decreased levels of ubiquitinated proteins, ATF3, CHOP, and the overall total cell death, suggesting that inhibition of protein synthesis increases cell survival by relieving proteotoxic stress. The NFV/BZ combination inhibited the growth of NSCLC xenografts, which correlated with the induction of markers of ER stress and apoptosis. Collectively, these data show that NFV and BZ enhance proteotoxicity in NSCLC and MM cells, and suggest that this combination could tip the precarious balance of protein homeostasis in cancer cells for therapeutic gain.


Asunto(s)
Ácidos Borónicos/toxicidad , Nelfinavir/toxicidad , Inhibidores de Proteasas/toxicidad , Pirazinas/toxicidad , Factor de Transcripción Activador 3/antagonistas & inhibidores , Factor de Transcripción Activador 3/genética , Factor de Transcripción Activador 3/metabolismo , Animales , Apoptosis/efectos de los fármacos , Ácidos Borónicos/uso terapéutico , Bortezomib , Proteínas Potenciadoras de Unión a CCAAT/antagonistas & inhibidores , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Caspasas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sinergismo Farmacológico , Estrés del Retículo Endoplásmico/efectos de los fármacos , Humanos , Ratones , Ratones Desnudos , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Nelfinavir/uso terapéutico , Inhibidores de Proteasas/uso terapéutico , Pirazinas/uso terapéutico , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Trasplante Heterólogo
9.
Mol Oral Microbiol ; 27(4): 308-23, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22759315

RESUMEN

Streptococcus mutans, a major pathogen of dental caries, is occasionally isolated from the blood of patients with infective endocarditis. Bacterial attachment of exposed collagen tissue in the impaired endothelium is an important step in the onset of infective endocarditis. In our previous studies, some S. mutans strains were shown to possess collagen-binding activities and most of them had an approximately 120-kDa cell-surface collagen-binding protein called Cnm. However, several strains without Cnm proteins show collagen-binding properties. In the present study, another collagen-binding protein, Cbm, was characterized and its coding gene cbm was sequenced in these strains. The amino acid alignment in the putative collagen-binding domain of Cbm was shown to have approximately 80% identity and 90% similarity to the comparable region of Cnm. Cbm-deficient isogenic mutant strains constructed by insertional inactivation of the cbm gene, lacked collagen-binding properties, which were recovered in the complemented mutant. Analyses of a large number of clinical isolates from Japan, Thailand and Finland revealed that cbm-positive strains were present in all of these countries and that cnm-positive and cbm-positive strains were detected in the oral cavity of approximately 10 and 2% of systemically healthy subjects, respectively. In addition, cnm-positive strains were predominantly identified in the serotype f group, whereas cbm-positive strains were frequently detected in serotype k. These results suggest that Cbm as well as Cnm are major cell surface proteins of S. mutans associated with binding to type I collagen and predominantly identified in serotype k strains.


Asunto(s)
Adhesinas Bacterianas/química , Colágeno Tipo I/metabolismo , Endocarditis Bacteriana/microbiología , Unión Proteica , Streptococcus mutans/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Niño , Preescolar , Femenino , Finlandia , Técnicas de Inactivación de Genes , Genes Bacterianos , Humanos , Japón , Masculino , Persona de Mediana Edad , Saliva/microbiología , Serotipificación , Streptococcus mutans/clasificación , Tailandia , Transformación Bacteriana , Virulencia/genética , Adulto Joven
10.
Appl Radiat Isot ; 69(12): 1721-4, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21367607

RESUMEN

Clear cell sarcoma (CCS) is a rare melanocytic malignant tumor with a poor prognosis. Our previous study demonstrated that in vitro cultured CCS cells have the ability to highly uptake l-BPA and thus boron neutron capture therapy could be a new option for CCS treatment. This paper proved that a remarkably high accumulation of (10)B (45-74 ppm) in tumor was obtained even in a CCS-bearing animal with a well-controlled biodistribution followed by intravenous administration of L-BPA-fructose complex (500 mg BPA/kg).


Asunto(s)
Compuestos de Boro/farmacocinética , Terapia por Captura de Neutrón de Boro , Fenilalanina/análogos & derivados , Sarcoma de Células Claras/radioterapia , Adolescente , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fenilalanina/farmacocinética , Sarcoma de Células Claras/metabolismo , Distribución Tisular
11.
Caries Res ; 45(1): 56-63, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21311187

RESUMEN

BACKGROUND: Oenothera biennis (evening primrose) seed extract (OBSE) is known to contain polyphenols, which may possess antioxidant activities. Polyphenols extracted from several plants are reported to exhibit cariostatic activities by inhibiting mutans streptococcus growth and glucosyltransferase activities. The purpose of the present study was to examine the inhibitory effects of OBSE on the development of dental caries, both in vitro and in vivo. METHODS: OBSE was investigated for its inhibitory effects on cellular aggregation, hydrophobicity, sucrose-dependent adherence and insoluble glucan synthesis. Furthermore, biofilm formation was examined in the presence of OBSE, using confocal microscopic imaging. An animal experiment was also performed to examine the in vivo effects. RESULTS: OBSE induced a strong aggregation of Streptococcus mutans MT8148 cells, while cell surface hydrophobicity was decreased by approximately 90% at a concentration of 0.25 mg/ml. The sucrose-dependent adherence of the MT8148 cells was also reduced by addition of OBSE, with a reduction rate of 73% seen at a concentration of 1.00 mg/ml. Additionally, confocal microscopic observations revealed the biofilm development phase to be remarkably changed in the presence of OBSE. Furthermore, insoluble glucan synthesis was significantly reduced when OBSE was present at concentrations greater than 0.03 mg/ml. In an animal experiment, the caries scores in rats given OBSE (0.05 mg/ml in drinking water) were significantly lower than those in rats given water without OBSE. CONCLUSION: Our results indicate that OBSE has inhibitory activity on dental caries.


Asunto(s)
Cariostáticos/uso terapéutico , Caries Dental/tratamiento farmacológico , Oenothera biennis , Fitoterapia , Extractos Vegetales/uso terapéutico , Streptococcus mutans/efectos de los fármacos , Animales , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Cariostáticos/farmacología , Caries Dental/microbiología , Glucanos/metabolismo , Glucosiltransferasas/antagonistas & inhibidores , Interacciones Hidrofóbicas e Hidrofílicas/efectos de los fármacos , Masculino , Extractos Vegetales/farmacología , Ratas , Ratas Sprague-Dawley , Semillas
12.
Oral Microbiol Immunol ; 24(3): 211-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19416450

RESUMEN

INTRODUCTION: Surface protein antigen (PAc) and glucosyltransferases (GTF) are major adhesive molecules of Streptococcus mutans, though the mechanism of their regulation has not been fully elucidated. METHODS: To investigate the regulation mechanism, we determined a nucleotide sequence in the upstream region of the pac locus in S. mutans and identified two open reading frames (ORF), designated as orf1 and orf2. Each ORF was inactivated and functional analyses were performed. RESULTS: Western blot analyses revealed that the expression level of PAc was unaffected, while that of cell-associated GTF was diminished in both mutant strains. Furthermore, they showed higher hydrophobicity levels and an impaired sucrose-dependent adherence to smooth surfaces. RNA dot blot analysis demonstrated that transcriptions of the gtfB and the gtfC genes, which encode GTF-I and GTF-SI, respectively, were downregulated, while that of pac was comparable to the wild-type strain. In addition, the GTF activities of the mutant strains were significantly lower than those of the wild-type, though a greater amount of total glucan produced by the mutants was noted in culture supernatants. CONCLUSION: These findings suggest that orf1 and orf2 are associated with positive regulation of the gtfB and gtfC genes.


Asunto(s)
Proteínas Bacterianas/genética , Regulación Enzimológica de la Expresión Génica/genética , Glucosiltransferasas/genética , Streptococcus mutans/genética , Antígenos Bacterianos/genética , Adhesión Bacteriana/genética , Western Blotting , Regulación hacia Abajo/genética , Electroforesis en Gel de Poliacrilamida , Glucanos/genética , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Immunoblotting , Proteínas de la Membrana/genética , Biología Molecular , Mutación/genética , Sistemas de Lectura Abierta/genética , Polisacáridos Bacterianos/genética , Sacarosa
13.
Appl Radiat Isot ; 67(7-8 Suppl): S109-10, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19395268
14.
Appl Radiat Isot ; 67(7-8 Suppl): S47-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19395269

RESUMEN

We treated 6 patients with recurrent oral cancer and metastasis to the cervical lymph nodes after conventional treatments in 5 and non-conventional in 1 using BNCT, and herein report our results. The clinical response in our patients ranged from CR to PD. In 5 cases, spontaneous pain decreased immediately after BNCT. Three of the 6 are alive at the time of writing and we found that BNCT contributed to QOL improvement in all.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Metástasis Linfática/radioterapia , Neoplasias de la Boca/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Compuestos de Boro/uso terapéutico , Femenino , Radioisótopos de Flúor , Humanos , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/diagnóstico por imagen , Neoplasias de la Boca/fisiopatología , Cuello , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/fisiopatología , Dolor/fisiopatología , Fenilalanina/análogos & derivados , Fenilalanina/uso terapéutico , Tomografía de Emisión de Positrones , Calidad de Vida , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Radiofármacos , Tomografía Computarizada por Rayos X
15.
Int J Oral Maxillofac Surg ; 38(3): 293-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19179044

RESUMEN

Boron neutron capture therapy (BNCT) is a tumor-selective radiation therapy using alpha and (7)Li particles, which are produced by the reaction of neutron with boron ((10)B), and taken up by the tumor. The authors report their first experience of BNCT on a patient with no history of surgery, chemotherapy or conventional radiotherapy for papillary cystadenocarcinoma in the upper lip.


Asunto(s)
Terapia por Captura de Neutrón de Boro/métodos , Cistadenocarcinoma Papilar/radioterapia , Neoplasias de los Labios/radioterapia , Anciano , Cistadenocarcinoma Papilar/patología , Femenino , Humanos , Neoplasias de los Labios/patología , Imagen por Resonancia Magnética , Dosis de Radiación , Resultado del Tratamiento
16.
J Dent Res ; 86(3): 242-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17314256

RESUMEN

Water-insoluble alpha-glucans are synthesized from sucrose by glucosyltransferase-I of mutans streptococci and play an important role in the development of dental plaque. Several types of beta-glucans in fungal cell wall components and water-soluble alpha-glucans from Streptococcus mutans are known to modulate innate immunity. In the present study, we investigated whether water-insoluble alpha-glucans also induced inflammatory innate immune responses. Our results showed that water-insoluble alpha-glucans synthesized by Streptococcus sobrinus activated mouse peritoneal exudate macrophages to produce pro-inflammatory cytokines. The immunological responses were not due to contamination by sucrose, water-soluble alpha-glucan, lipopolysaccharide, or peptidoglycan. Furthermore, human monocytes stimulated by water-insoluble alpha-glucans produced TNF-alpha and IL-8, while human polymorphonuclear cells were activated by water-insoluble alpha-glucans, resulting in chemotaxis and hydrogen peroxide production. The results demonstrated that water-soluble alpha-glucans modulate macrophage- and granulocyte-induced inflammatory immune responses, and suggest that inflammation induced by those alpha-glucans is associated with the development of periodontal diseases.


Asunto(s)
Citocinas/biosíntesis , Glucanos/farmacología , Mediadores de Inflamación/metabolismo , Macrófagos Peritoneales/efectos de los fármacos , Monocitos/efectos de los fármacos , Animales , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/farmacología , Línea Celular , Quimiotaxis de Leucocito , Femenino , Glucanos/inmunología , Humanos , Ratones , Ratones Endogámicos BALB C , Activación Neutrófila , Solubilidad , Estreptococos Viridans/fisiología
17.
Phys Rev Lett ; 95(10): 107005, 2005 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-16196956

RESUMEN

While Josephson-junction-like structures intrinsic to the layered cuprate high temperature superconductors offer an attractive stage for exploiting possible applications to new quantum technologies, the low energy quasiparticle excitations characteristically present in these d-wave superconductors may easily destroy the coherence required. Here we demonstrate for the first time the feasibility of macroscopic quantum tunneling in the intrinsic Josephson junctions of a high temperature superconductor Bi(2)Sr(2)CaCu(2)O(8 + delta), and find it to be characterized by a high classic-to-quantum crossover temperature and a relatively weak quasiparticle dissipation.

18.
J Dent Res ; 83(11): 874-9, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15505239

RESUMEN

Glucosyltransferases (GTF)-I and GTF-SI of Streptococcus mutans synthesize water-insoluble and both water-soluble and -insoluble glucans, respectively, and play essential roles in the sucrose-dependent adhesion of the organism to tooth surfaces. To examine the interactions of different GTFs on artificial biofilm formed by S. mutans and other oral streptococci, we generated GTF-I- and GTF-SI-hyperproducing isogenic mutant strains. Transformant B42-21, which hyperexpressed GTF-SI, exhibited firm adhesion in the presence of sucrose, whereas transformant B42-10, which hyperexpressed GTF-I, failed to exhibit firm adhesion. Furthermore, co-culture of transformant B42-21 with water-soluble glucan-synthesizing Streptococcus sanguinis yielded firm adhesion, while the addition of dextran T10 to B42-21 growing culture had no effect on adhesion. These findings suggest that GTF-SI has a strong effect on sucrose-dependent adhesion and is essential for biofilm formation on smooth surfaces, in cooperation with water-soluble glucans synthesized de novo by oral streptococci that inherently lack cell adhesion ability.


Asunto(s)
Adhesión Bacteriana/fisiología , Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Glucosiltransferasas/metabolismo , Streptococcus/enzimología , Análisis de Varianza , Western Blotting , Técnicas de Cocultivo , Ecosistema , Electroforesis en Gel de Poliacrilamida , Vectores Genéticos , Glucanos/biosíntesis , Solubilidad , Especificidad de la Especie , Streptococcus/genética , Streptococcus/fisiología , Streptococcus mutans/enzimología , Streptococcus mutans/genética , Streptococcus mutans/fisiología , Transformación Bacteriana
19.
Cell Mol Life Sci ; 61(11): 1257-65, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15170505

RESUMEN

Mammalian blood coagulation is based on the proteolytically induced polymerization of fibrinogens. Initially, fibrin monomers noncovalently interact with each other. The resulting homopolymers are further stabilized when the plasma transglutaminase (TGase) intermolecularly cross-links epsilon-(gamma-glutamyl)lysine bonds. In crustaceans, hemolymph coagulation depends on the TGase-mediated cross-linking of specific plasma-clotting proteins, but without the proteolytic cascade. In horseshoe crabs, the proteolytic coagulation cascade triggered by lipopolysaccharides and beta-1,3-glucans leads to the conversion of coagulogen into coagulin, resulting in noncovalent coagulin homopolymers through head-to-tail interaction. Horseshoe crab TGase, however, does not cross-link coagulins intermolecularly. Recently, we found that coagulins are cross-linked on hemocyte cell surface proteins called proxins. This indicates that a cross-linking reaction at the final stage of hemolymph coagulation is an important innate immune system of horseshoe crabs.


Asunto(s)
Proteínas Sanguíneas/química , Proteínas Sanguíneas/fisiología , Cangrejos Herradura/química , Animales , Coagulación Sanguínea , Dimerización , Hemocitos/química , Hemocitos/fisiología
20.
J Periodontal Res ; 37(6): 425-32, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12472836

RESUMEN

Porphyromonas gingivalis fimbriae are critical for the promotion of bacterial infection. The fimA gene encoding fimbrillin, a subunit of fimbriae, has been classified into five genotypes (types I to V) based on their nucleotide sequences. Using a fimA type-specific PCR assay, our previous study demonstrated a close relationship between P. gingivalis possessing type II and type IV fimA genes and adult periodontitis. In that study, some clinical specimens were found to be positive for both types I- and II- fimA specific primers, likely due to the coexistence of two clonal types or a single clone of an unknown genotype in the samples. In the present study, we cloned a new variant of the fimA gene, designated as type Ib fimA, from P. gingivalis HG1691. The nucleotide sequence of the cloned fimA gene showed a 97.1% homology with that of type I fimA, indicating it as a clonal variant of type I fimA. Organisms with type Ib fimA were detected in 13.5% of periodontitis patients and in 2.9% of periodontal healthy adults. Statistical analysis revealed a strong relationship between periodontitis and specific fimA types such as type Ib [odds ratio (OR) 6.51], type II (OR 77.8), and type IV (OR 7.54). Moreover, type Ib fimA-organisms were also found to be related to periodontitis in Down's syndrome (OR 1.91) and mentally disabled populations (OR 4.00). These findings suggest that P. gingivalis with type Ib fimA is closely associated with the progression of periodontitis, similar to organisms with type II and IV fimA.


Asunto(s)
Proteínas Fimbrias/genética , Periodontitis/microbiología , Personas con Discapacidades Mentales , Pili Sexual/genética , Porphyromonas gingivalis/genética , Adulto , Anciano , Secuencia de Bases , Estudios de Casos y Controles , Células Clonales , Intervalos de Confianza , Placa Dental/microbiología , Síndrome de Down/microbiología , Femenino , Proteínas Fimbrias/clasificación , Genotipo , Humanos , Discapacidad Intelectual/microbiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Pili Sexual/clasificación , Porphyromonas gingivalis/clasificación , Homología de Secuencia de Ácido Nucleico
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