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1.
Phys Rev Lett ; 130(5): 051801, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36800472

RESUMEN

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νßß) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>2.3×10^{26} yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

2.
Clin Radiol ; 77(11): 855-863, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36055826

RESUMEN

AIM: To evaluate the usefulness of synthetic magnetic resonance imaging (MRI) performed before the initiation of neoadjuvant chemotherapy (NAC) in predicting whether breast cancers can achieve a pathological complete response (pCR) after the completion of NAC. MATERIALS AND METHODS: This retrospective study investigated 37 consecutive patients with 39 breast cancers (pCR: 14, and non-pCR: 25) who underwent dynamic contrast-enhanced (DCE)-MRI and synthetic MRI before the initiation of NAC. Using synthetic MRI images, quantitative values (T1 and T2 relaxation times, proton density [PD] and their standard deviations [SD]) were obtained in breast lesions, before (Pre-T1, Pre-T2, Pre-PD, SD of Pre-T1, SD of Pre-T2, SD of Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD, SD of Gd-T1, SD of Gd-T2, SD of Gd-PD) contrast agent injection. The aforementioned quantitative values and several morphological features that were identified on DCE-MRI were compared between pCR and non-pCR. RESULTS: Multivariate analyses revealed that the SD of Pre-T2 (p=0.038) was significant and was an independent predictor of pCR, with an area under the receiver operating characteristics curve of 0.829. The sensitivity, specificity, and accuracy of the SD of Pre-T2 with an optimal cut-off value of 11.5 were 71.4%, 80%, and 76.3%, respectively. CONCLUSIONS: The SD of Pre-T2 obtained from synthetic MRI was used successfully to predict those breast cancers that would achieve a pCR after the completion of NAC; however, these results are preliminary and need to be verified by further studies.


Asunto(s)
Neoplasias de la Mama , Terapia Neoadyuvante , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Medios de Contraste/uso terapéutico , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Terapia Neoadyuvante/métodos , Protones , Estudios Retrospectivos , Resultado del Tratamiento
3.
Int J Oral Maxillofac Surg ; 50(3): 316-322, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32826125

RESUMEN

In the head and neck region, preoperative evaluation of the free flap volume is challenging. The current study validated preoperative three-dimensional (3D) virtual surgical simulation for soft tissue reconstruction by assessing flap volume and evaluated fat and muscle volume changes at follow-up in 13 head and neck cancer patients undergoing anterolateral craniofacial resection. Patients received 3D virtual surgical simulation, and the volume of the planned defects was estimated by surgical simulation. Following en bloc resection of the tumor, the defect in the skull base was covered using a rectus abdominis myocutaneous flap. Following surgery, computed tomography scans were acquired at day 1 and at 6 and 12 months. Virtual planned defect was on average 227 ml (range, 154-315) and was 10% smaller than the actual flap volume in patients without skin involvement of the tumor. Between day 1 and 12 months post-surgery, the volume of fat and muscle tissue in the free flap dropped by 9% and 58%, respectively. Our results indicate that 3D virtual surgical simulation provides essential information in determining the accurate volume of the required free flap for surgical defect repair and may thus help improve surgical planning and functional and esthetic outcome.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Colgajo Miocutáneo , Procedimientos de Cirugía Plástica , Estética Dental , Estudios de Factibilidad , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/cirugía , Humanos
4.
Clin Radiol ; 75(5): 398.e1-398.e8, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32019671

RESUMEN

AIM: To evaluate the utility of synthetic magnetic resonance imaging (MRI) of the breast in predicting the Ki-67 status in patients with oestrogen receptor (ER)-positive breast cancer. MATERIALS AND METHODS: Forty-nine patients with 50 histopathologically proven breast cancers who underwent additional synthetic MRI were enrolled in the present study. Using synthetic MRI images, T1 and T2 relaxation times and their standard deviations (SD) in the breast lesions before (T1-Pre, T2-Pre, PD-Pre, SD of T1-Pre, SD of T2-Pre, SD of PD-Pre) and after (T1-Gd, T2-Gd, PD-Gd, SD of T1-Gd, SD of T2-Gd, SD of PD-Gd) contrast agent injection were obtained. These quantitative values were compared between the low Ki-67 expression (<14%) lesions (low-proliferation group: n=23) and high Ki-67 expression (≥14%) lesions (high-proliferation group: n=27). RESULTS: The univariate analysis showed that the SD of T1-Gd (p<0.001) and T2-Gd (p=0.042) were significantly higher in the high-proliferation group than in the low-proliferation group. Multivariate analysis further showed that the SD of T1-Gd was a significant and independent predictor of Ki-67 expression, with an area under the receiver operating characteristic (AUROC) curve of 0.885. The sensitivity, specificity, and accuracy of the SD of T1-Gd with an optimal cut-off value of 98.5 were 77.8%, 87%, and 82%, respectively. CONCLUSION: The SD of T1-Gd obtained from synthetic MRI was useful to predict Ki-67 status.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/metabolismo , Antígeno Ki-67/metabolismo , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Medios de Contraste , Estudios de Factibilidad , Femenino , Humanos , Aumento de la Imagen/métodos , Biopsia Guiada por Imagen , Persona de Mediana Edad , Receptores de Estrógenos/metabolismo , Estudios Retrospectivos , Sensibilidad y Especificidad
5.
Phys Rev Lett ; 122(19): 192501, 2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31144924

RESUMEN

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

6.
Transl Psychiatry ; 7(4): e1106, 2017 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-28440811

RESUMEN

We evaluated the circadian phenotypes of patients with delayed sleep-wake phase disorder (DSWPD) and non-24-hour sleep-wake rhythm disorder (N24SWD), two different circadian rhythm sleep disorders (CRSDs) by measuring clock gene expression rhythms in fibroblast cells derived from individual patients. Bmal1-luciferase (Bmal1-luc) expression rhythms were measured in the primary fibroblast cells derived from skin biopsy samples of patients with DSWPD and N24SWD, as well as control subjects. The period length of the Bmal1-luc rhythm (in vitro period) was distributed normally and was 22.80±0.47 (mean±s.d.) h in control-derived fibroblasts. The in vitro periods in DSWPD-derived fibroblasts and N24SWD-derived fibroblasts were 22.67±0.67 h and 23.18±0.70 h, respectively. The N24SWD group showed a significantly longer in vitro period than did the control or DSWPD group. Furthermore, in vitro period was associated with response to chronotherapy in the N24SWD group. Longer in vitro periods were observed in the non-responders (mean±s.d.: 23.59±0.89 h) compared with the responders (mean±s.d.: 22.97±0.47 h) in the N24SWD group. Our results indicate that prolonged circadian periods contribute to the onset and poor treatment outcome of N24SWD. In vitro rhythm assays could be useful for predicting circadian phenotypes and clinical prognosis in patients with CRSDs.


Asunto(s)
Ritmo Circadiano/genética , Fibroblastos/metabolismo , Trastornos del Sueño del Ritmo Circadiano/genética , Trastornos del Sueño-Vigilia/metabolismo , Factores de Transcripción ARNTL/metabolismo , Adulto , Cronoterapia/métodos , Ritmo Circadiano/fisiología , Femenino , Humanos , Japón/epidemiología , Luciferasas/metabolismo , Masculino , Persona de Mediana Edad , Fenotipo , Trastornos del Sueño del Ritmo Circadiano/fisiopatología , Trastornos del Sueño del Ritmo Circadiano/terapia , Trastornos del Sueño-Vigilia/terapia , Resultado del Tratamiento
7.
J Laryngol Otol ; 130(10): 914-922, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27604559

RESUMEN

OBJECTIVES: To verify the effectiveness and safety of the addition of adipose-derived regenerative cells to autologous fat injection therapy. METHODS: Unilateral vocal fold paralysis models were made by cutting the right recurrent laryngeal nerve in two pigs. At day 30, 0.5 ml adipose-derived regenerative cells mixed with 1 ml autologous fat was injected into the right vocal fold of one pig, with the other receiving 0.5 ml Ringer's solution mixed with 1 ml autologous fat. At day 120, fibrescopy, laser Doppler flowmeter, computed tomography, vocal function evaluation and histological assessment were conducted. RESULTS: Although histological assessment revealed atrophy of the thyroarytenoid muscle fibre in both pigs, there was remarkable hypertrophy of the thyroarytenoid muscle fibre in the area surrounding the adipose-derived regenerative cells injection site. CONCLUSION: The addition of a high concentration of adipose-derived regenerative cells to autologous fat injection therapy has the potential to improve the treatment outcome for unilateral vocal fold paralysis.


Asunto(s)
Adipocitos/trasplante , Tejido Adiposo/trasplante , Trasplante de Células Madre/métodos , Parálisis de los Pliegues Vocales/terapia , Adipocitos/citología , Tejido Adiposo/citología , Animales , Modelos Animales de Enfermedad , Hipertrofia/etiología , Músculos Laríngeos/patología , Laringe/patología , Atrofia Muscular/etiología , Proyectos Piloto , Porcinos , Trasplante Autólogo , Resultado del Tratamiento , Pliegues Vocales/patología
8.
Orthop Traumatol Surg Res ; 99(2): 247-51, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23477792

RESUMEN

Local tumor compression is the main mechanical cause of posterior interosseous nerve (PIN) palsy. The reported cases of these tumors do not include that of pigmented villonodular synovitis (PVNS). Here, we report a case of a 53-year-old male with a 9-year history of painless swelling in his left elbow and a few months of progressive weakness in his left hand. Imaging identified the mass, and histological examination of the biopsy specimens revealed PVNS. The mass was compressing the nerve at the arcade of Frohse, and we performed a complete resection of the mass. Following removal of the mass, the patient regained complete function in his left upper extremity, and no local recurrence has been detected after 2 postoperative years. The possibility of PVNS should be considered in the differential diagnosis of PIN palsy.


Asunto(s)
Mononeuropatías/etiología , Sinovitis Pigmentada Vellonodular/complicaciones , Articulación del Codo/diagnóstico por imagen , Antebrazo/inervación , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Nervio Radial/anatomía & histología , Radiografía , Recuperación de la Función , Neoplasias de los Tejidos Blandos/complicaciones , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/cirugía , Sinovitis Pigmentada Vellonodular/diagnóstico
9.
Cell Death Dis ; 3: e395, 2012 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-23034330

RESUMEN

In this study, the roles of p53 in impaired spermatogenic male germ cells of p53-deficient medaka were investigated by analyzing histological changes, and gene expressions of 42Sp50, Oct 4 and vitellogenin (VTG2) by RT-PCR or in situ hybridization in the testes. We found that a small number of oocyte-like cells (testis-ova) differentiated spontaneously in the cysts of type A and early type B spermatogonia in the p53-deficient testes, in contrast to the wild-type (wt) testes in which testis-ova were never found. Furthermore, ionizing radiation (IR) irradiation increased the number of testis-ova in p53-deficient testes, increased testis-ova size and proceeded up to the zygotene or pachytene stages of premature meiosis within 14 days after irradiation. However, 28 days after irradiation, almost all the testis-ova were eliminated presumably by p53-independent apoptosis, and spermatogenesis was restored completely. In the wt testis, IR never induced testis-ova differentiation. This is the first study to demonstrate the pivotal role of the p53 gene in the elimination of spontaneous testis-ova in testes, and that p53 is not indispensable for the restoration of spermatogenesis in the impaired testes in which cell cycle regulation is disturbed by IR irradiation.


Asunto(s)
Rayos gamma , Meiosis/efectos de la radiación , Espermatogonias/citología , Proteína p53 Supresora de Tumor/metabolismo , Animales , Diferenciación Celular/efectos de la radiación , Masculino , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Oryzias/crecimiento & desarrollo , Factores de Elongación de Péptidos/metabolismo , Espermatogénesis/efectos de la radiación , Espermatogonias/metabolismo , Espermatogonias/efectos de la radiación , Testículo/citología , Testículo/metabolismo , Testículo/patología , Proteína p53 Supresora de Tumor/deficiencia , Proteína p53 Supresora de Tumor/genética , Vitelogeninas/metabolismo , Proteínas de Xenopus/metabolismo
10.
Med J Malaysia ; 63 Suppl A: 41, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19024974

RESUMEN

Two types of cell therapy for facial anti-aging in my clinical experience are introduced in this presentation. One therapy is cultured gingival fibroblasts injection. This procedure lasts for at least one year, making it a good option for patients. The other is platelet rich plasma injection. The results of the preliminary data are promising, but not yet well understood. More clinical data and long-term follow-up is needed.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Fibroblastos , Encía/trasplante , Mucosa Bucal/trasplante , Envejecimiento de la Piel/fisiología , Fenómenos Fisiológicos de la Piel , Piel/patología , Adulto , Anciano , Plaquetas , Células Cultivadas , Técnicas Cosméticas , Femenino , Encía/fisiología , Humanos , Persona de Mediana Edad , Mucosa Bucal/fisiología , Plasma Rico en Plaquetas , Envejecimiento de la Piel/patología
11.
Arch Virol ; 152(5): 861-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17277903

RESUMEN

We screened in vitro antiviral activity against a salmonid pathogenic virus, infectious hematopoietic necrosis virus (IHNV), from the extracts of a total of 342 species of marine algae collected from the Japanese coastline. The anti-IHNV activity was found primarily in MeOH extracts, and the extract from one marine brown alga in particular, Eisenia bicyclis, showed high anti-IHNV activity. The anti-IHNV compound was isolated and purified as MC15 from the E. bicyclis extract, and the chemical structure was determined by several spectrometric analyses. The antiviral compound was proved to be a chlorophyll c2 derivative lacking the metal ion Mg(2+). MC15 showed similar antiviral activity against other salmonid enveloped viruses such as Paralichthys olivaceus virus and Oncorhynchus masou virus, and stability against any pH and temperatures up to 100 degrees C. No cytotoxicity was observed at up to 5 microg/ml. The antiviral mechanism of MC15 appears to be direct inactivation of the viral particles. A time course study showed that the inactivation of IHNV was completed within 40 min when 200 PFU of IHNV was reacted with MC15 at 800 ng/ml.


Asunto(s)
Clorofila/farmacología , Virus de la Necrosis Hematopoyética Infecciosa/efectos de los fármacos , Phaeophyceae/química , Inactivación de Virus , Animales , Línea Celular , Clorofila/química , Clorofila/aislamiento & purificación , Calor , Concentración de Iones de Hidrógeno , Virus de la Necrosis Hematopoyética Infecciosa/crecimiento & desarrollo , Japón , Biología Marina , Océanos y Mares , Salmonidae/virología , Factores de Tiempo , Ensayo de Placa Viral
12.
Genome Dyn ; 2: 165-182, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-18753778

RESUMEN

Medaka (Oryzias latipes) is widely used in research in the fields of biology, medicine, environmental science and fisheries. Zebrafish and medaka are well established as genetic model systems in which large-scale mutagenesis has been successfully performed, and for which EST data, BAC libraries, and fine linkage maps have been accumulated. Among rayfinned fish, there is a large evolutionary distance between medaka and zebrafish. In contrast, the evolutionary distance between medaka and two species of pufferfish, fugu (Takifugu rubripes), and tetraodon (Tetraodon nigroviridis), is almost comparable to that between humans and rodents, and the current genome project is showing that their genome organization is well conserved. Comparison of genome structure among teleosts and mammals helps our understanding of the orthologous gene structure and the evolution of gene families in vertebrates. In addition, gene functions have to be analyzed by both forward and reverse genetics. The Targeting Induced Local Lesions IN Genome (TILLING) system, which includes random mutagenesis, followed by screening for induced mutations in the target genes, is a powerful tool for studying the functional genomics of both medaka and zebrafish.


Asunto(s)
Genómica/métodos , Oryzias/genética , Animales , Secuencia de Bases , Biología Computacional , Evolución Molecular , Genoma , Humanos , Cariotipificación , Datos de Secuencia Molecular , Filogenia , Polimorfismo Genético , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
13.
J Endocrinol ; 185(1): 187-95, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15817839

RESUMEN

Several steroidogenic cell lines of granulosa cells (GC) have been used to elucidate differentiation mechanisms of GC during folliculogenesis. These cell lines, however, are of limited usefulness since they have lost some of their differentiation potential. The transcription factor adrenal-4 binding protein (Ad4BP), also known as steroidogenic factor-1 or NR5A1, is essential for the expression of all P-450 steroidogenic enzymes. By transfection with the Ad4BP gene together with SV40 DNA, we have generated several steroidogenic cell lines. One selective clone, named 4B2, retained its steroidogenic potential and was therefore analyzed in depth. This cell line responded to 8-Br-cAMP by displaying differentiation characteristics similar to those occurring in the differentiation process of primary cultured GC, including enhanced progesterone secretion, a cell shape change from a fibroblastic to epithelioid conformation, elongated mitochondria, increased gap junction formation and inhibition of cell proliferation. Prostaglandin E2 (PGE2), an intraovarian regulator of GC, stimulated cAMP production, and this eicosanoid, like 8-Br-cAMP, induced differentiation properties with the exception of cell conformation in 4B2 cells. These results suggest that expression of Ad4BP may provide the basis for a repertoire of cAMP-sensitive differentiation properties, including morphological alterations and growth inhibition. Thus, the 4B2 cell line may serve as a tool for elucidation of differentiation mechanisms that are under the control of Ad4BP.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Proteínas de Unión al ADN/genética , Células de la Granulosa/metabolismo , Esteroides/biosíntesis , Factores de Transcripción/genética , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Animales , Antígenos Transformadores de Poliomavirus/análisis , Antígenos Transformadores de Poliomavirus/metabolismo , Diferenciación Celular , Línea Celular , AMP Cíclico/metabolismo , Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/metabolismo , Dinoprostona/farmacología , Femenino , Uniones Comunicantes/ultraestructura , Células de la Granulosa/citología , Células de la Granulosa/ultraestructura , Proteínas de Homeodominio , Inmunohistoquímica/métodos , Ratones , Mitocondrias/ultraestructura , Progesterona/análisis , Radioinmunoensayo/métodos , Receptores Citoplasmáticos y Nucleares , Factor Esteroidogénico 1 , Factores de Transcripción/análisis , Factores de Transcripción/metabolismo , Transfección/métodos
14.
Neuroscience ; 132(3): 633-43, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15837125

RESUMEN

We previously found that the methanol extract of a marine brown alga, Sargassum macrocarpum showed marked nerve growth factor (NGF)-dependent neurite outgrowth promoting activity to PC12D cells. The active substance purified was elucidated to be sargachromenol. The median effective dose (ED50) was 9 microM against PC12D cells in the presence of 10 ng/ml NGF, although it showed no neurotrophic effect on its own. Pretreatment of cells with protein kinase A (PKA) inhibitor or U0126 substantially suppressed the sargachromenol-enhanced neurite outgrowth from PC12D cells, suggesting that the activation of cyclic AMP-mediated protein kinase and mitogen-activated protein (MAP) kinase 1/2 was apparently required for the action of sargachromenol. On the other hand, sargachromenol significantly promoted the survival of neuronal PC12D cells at 0-50 ng/ml NGF in serum-free medium. Neither PKA inhibitor nor U0126 could inhibit the survival supporting effect of sargachromenol, whereas wortmannin significantly blocked the sargachromenol-induced survival supporting effect on neuronal PC12D cells, suggesting that sargachromenol rescued neuronal PC12D cells by activating phosphatidylinositol-3 kinase. These results demonstrate that sargachromenol promotes neuronal differentiation of PC12D cells and supports the survival of neuronal PC12D cells via two distinct signaling pathways.


Asunto(s)
Benzopiranos/farmacología , Factor de Crecimiento Nervioso/farmacología , Neuritas/efectos de los fármacos , Sargassum/química , Transducción de Señal/efectos de los fármacos , Animales , Benzopiranos/aislamiento & purificación , Western Blotting , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Corteza Cerebral/citología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Embrión de Mamíferos , Inhibidores Enzimáticos/farmacología , Ratones , Ratones Endogámicos ICR , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Nardostachys/fisiología , Factor de Crecimiento Nervioso/análogos & derivados , Factor de Crecimiento Nervioso/química , Factor de Crecimiento Nervioso/aislamiento & purificación , Neuritas/fisiología , Neuronas/citología , Neuronas/efectos de los fármacos , Células PC12 , Ratas
15.
Appl Microbiol Biotechnol ; 62(4): 407-13, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12764553

RESUMEN

Previously we reported an antifungal protein specific to Pythium porphyrae, a causative agent of red rot disease afflicting seaweed Porphyra spp. This study was carried out to identify the antifungal mechanism of the antifungal protein to P. porphyrae. When we first examined the effect of an anti- Pythium protein (SAP) on the P. porphyrae cell walls, SAP did not decompose the six structural polysaccharides in Pythium cell walls. However, hyphal growth was significantly inhibited in Pythium cells treated with 50 microg/ml of SAP by MTT assay. Protoplasmic leakage was observed in P. porphyrae hyphae treated with SAP for 1 h, followed by hyphal swelling and disintegration, using SYTOX Green, and SAP permeabilized the membrane of P. porphyrae in a dose-dependent manner. Treating P. porphyrae cells with SAP in the presence of carbonyl cyanide m-chlorophenylhydrazone (CCCP), a membrane-depolarizing agent, significantly reduced the membrane permeability to SYTOX Green. Moreover, a similar effect was observed when the P. porphyrae cells were treated with SAP in the presence of MgCl2. In contrast, identical treatment in the presence of KCl significantly increased the membrane permeability to SYTOX Green. These results suggested that anti- Pythium mechanism of SAP was related to alteration of the membrane permeability in P. porphyrae.


Asunto(s)
Antifúngicos/farmacología , Proteínas Bacterianas/farmacología , Porphyra/microbiología , Pythium/efectos de los fármacos , Agua de Mar/microbiología , Streptomyces/metabolismo , Antifúngicos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Pared Celular/metabolismo , Colorantes Fluorescentes/metabolismo , Microscopía Fluorescente , Compuestos Orgánicos , Enfermedades de las Plantas/microbiología
16.
Appl Microbiol Biotechnol ; 61(2): 140-9, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12655456

RESUMEN

The pchA gene encoding chitinase A (PchA) from a Pythium porphyrae cell-wall-degrading marine bacterium, Pseudomonas sp. PE2, was cloned and characterized. The deduced PchA was a modular enzyme composed of an N-terminal signal peptide, a glycoside hydrolase family 18 catalytic domain that was responsible for the chitinase activity, the chitin-binding domains (ChBDs), and the carbohydrate-binding modules (CBM). The amino acid sequence of ChBD(PchA) was highly conserved in the CBM family 12 that also accommodates ChBDs without an AKWWTQG motif, a domain commonly found in bacterial chitinase and Streptomyces griseus protease C. Interestingly, CBM(PchA) showed significant sequence homology to the C-terminal region of endoglucanase B from Cellvibrio mixtus, which is a member of CBM family 6. This is the first report of a chitinase possessing a domain with high similarity to CBM family 6. Deletion analysis indicated clearly that ChBD(PchA) might play an important role in the binding of native chitin and chitosan, but not processed chitin. CBM(PchA) also appeared to play such a role in the binding of xylan and Avicel. These results suggest that the C-terminal region of PchA might be a key component in the binding of chitin in the cell walls of P. porphyrae or other structural components of marine organisms.


Asunto(s)
Quitinasas , Clonación Molecular , Pseudomonas/enzimología , Agua de Mar/microbiología , Secuencia de Aminoácidos , Secuencia de Bases , Dominio Catalítico , Quitina/metabolismo , Quitinasas/química , Quitinasas/genética , Quitinasas/metabolismo , Datos de Secuencia Molecular , Filogenia , Pseudomonas/genética , Pseudomonas/crecimiento & desarrollo , Análisis de Secuencia de ADN , Especificidad por Sustrato
17.
Cell Death Differ ; 8(10): 977-84, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11598795

RESUMEN

Neuronal cell death, abnormal protein aggregates, and cytoplasmic vacuolization are major pathologies observed in many neurodegenerative disorders such as the polyglutamine (polyQ) diseases, prion disease, Alzheimer disease, and the Lewy body diseases, suggesting common mechanisms underlying neurodegeneration. Here, we have identified VCP/p97, a member of the AAA+ family of ATPase proteins, as a polyQ-interacting protein in vitro and in vivo, and report on its characterization. Endogenous VCP co-localized with expanded polyQ (ex-polyQ) aggregates in cultured cells expressing ex-polyQ, with nuclear inclusions in Huntington disease patient brains, and with Lewy bodies in patient samples. Moreover, the expression of VCP mutants with mutations in the 2nd ATP binding domain created cytoplasmic vacuoles, followed by cell death. Very similar vacuoles were also induced by ex-polyQ expression or proteasome inhibitor treatment. These results suggest that VCP functions not only as a recognition factor for abnormally folded proteins but also as a pathological effector for several neurodegenerative phenotypes. VCP may thus be an ideal molecular target for the treatment of neurodegenerative disorders.


Asunto(s)
Proteínas de Ciclo Celular/fisiología , Muerte Celular , Enfermedades Neurodegenerativas/etiología , Enfermedades Neurodegenerativas/patología , Neuronas/citología , Vacuolas/ultraestructura , Adenosina Trifosfatasas , Animales , Proteínas de Ciclo Celular/genética , Enfermedad de Huntington/etiología , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/patología , Cuerpos de Inclusión/metabolismo , Mutación , Enfermedades Neurodegenerativas/metabolismo , Neuronas/metabolismo , Neuronas/ultraestructura , Células PC12 , Péptidos/metabolismo , Fenotipo , Ratas , Proteína que Contiene Valosina
18.
Ann Plast Surg ; 47(4): 450-2, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11601585

RESUMEN

The authors report a case of a free fibular graft that was successful as a result of venous return delivered through the bone marrow. A 26-year-old man underwent reconstruction of the left tibia and a soft-tissue defect of the lower leg. A free vascularized fibular bone and skin flap was elevated. The fibular vessels were anastomosed to the dorsalis pedis vessels. The elevated fibular bone was fixed to the tibia. The next day, reanastomosis was necessary because of venous thrombosis. However, the fibular vein rethrombosed, but blood flow was ascertained by Doppler flowmetry, with darker blood flow being recognized from the edge of the flap. Four days after surgery, the skin color gradually improved, and the flap had almost completely taken. On retrospective evaluation, the authors concluded that this flap succeeded because venous return was routed through the bone marrow in the free fibular graft.


Asunto(s)
Anastomosis Quirúrgica , Médula Ósea/irrigación sanguínea , Peroné/irrigación sanguínea , Peroné/trasplante , Trasplante de Piel , Colgajos Quirúrgicos/irrigación sanguínea , Tibia/irrigación sanguínea , Tibia/cirugía , Adulto , Drenaje , Humanos , Flujometría por Láser-Doppler , Masculino , Complicaciones Posoperatorias , Procedimientos de Cirugía Plástica/métodos , Venas , Trombosis de la Vena/etiología
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