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1.
Phys Rev Lett ; 113(10): 101801, 2014 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-25238348

RESUMEN

The trilepton nucleon decay modes p→e+νν and p→µ+νν violate |Δ(B-L)| by two units. Using data from a 273.4 kt yr exposure of Super-Kamiokande a search for these decays yields a fit consistent with no signal. Accordingly, lower limits on the partial lifetimes of τp→e+νν>1.7×10(32) years and τp→µ+νν>2.2×10(32) years at a 90% confidence level are obtained. These limits can constrain Grand Unified Theories which allow for such processes.

2.
Phys Rev Lett ; 113(12): 121802, 2014 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-25279622

RESUMEN

We present the results of searches for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ using data from a combined 172.8 kt·yr exposure of Super-Kamiokande-I,-II, and-III. We set lower limits on the partial lifetime for each of these modes: τn→ν[over ¯]π0>1.1×10(33) years and τp→ν[over ¯]π+>3.9×10(32) years at a 90% confidence level.

3.
Phys Rev Lett ; 112(9): 091805, 2014 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-24655245

RESUMEN

We report an indication that the elastic scattering rate of solar B8 neutrinos with electrons in the Super-Kamiokande detector is larger when the neutrinos pass through Earth during nighttime. We determine the day-night asymmetry, defined as the difference of the average day rate and average night rate divided by the average of those two rates, to be [-3.2 ± 1.1(stat) ± 0.5(syst)]%, which deviates from zero by 2.7 σ. Since the elastic scattering process is mostly sensitive to electron-flavored solar neutrinos, a nonzero day-night asymmetry implies that the flavor oscillations of solar neutrinos are affected by the presence of matter within the neutrinos' flight path. Super-Kamiokande's day-night asymmetry is consistent with neutrino oscillations for 4 × 10(-5) eV(2) ≤ Δm 2(21) ≤ 7 × 10(-5) eV(2) and large mixing values of θ12, at the 68% C.L.

4.
Phys Rev Lett ; 112(13): 131803, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24745406

RESUMEN

A search for the dinucleon decay pp → K+ K+ has been performed using 91.6 kton·yr data from Super-Kamiokande-I. This decay provides a sensitive probe of the R-parity-violating parameter λ112''. A boosted decision tree analysis found no signal candidates in the data. The expected background was 0.28±0.19 atmospheric neutrino induced events and the estimated signal detection efficiency was 12.6%±3.2%. A lower limit of 1.7×10(32) years has been placed on the partial lifetime of the decay O16 → C14K+ K+ at 90% C.L. A corresponding upper limit of 7.8×10(-9) has been placed on the parameter λ112''.

5.
Phys Rev Lett ; 110(18): 181802, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23683190

RESUMEN

Super-Kamiokande atmospheric neutrino data were fit with an unbinned maximum likelihood method to search for the appearance of tau leptons resulting from the interactions of oscillation-generated tau neutrinos in the detector. Relative to the expectation of unity, the tau normalization is found to be 1.42 ± 0.35(stat)(-0.12)(+0.14)(syst) excluding the no-tau-appearance hypothesis, for which the normalization would be zero, at the 3.8σ level. We estimate that 180.1 ± 44.3(stat)(-15.2)(+17.8) (syst) tau leptons were produced in the 22.5 kton fiducial volume of the detector by tau neutrinos during the 2806 day running period. In future analyses, this large sample of selected tau events will allow the study of charged current tau neutrino interaction physics with oscillation produced tau neutrinos.

6.
Rev Sci Instrum ; 94(7)2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37498166

RESUMEN

The Kamioka Gravitational wave detector (KAGRA) cryogenic gravitational-wave observatory has commenced joint observations with the worldwide gravitational wave detector network. Precise calibration of the detector response is essential for accurately estimating parameters of gravitational wave sources. A photon calibrator is a crucial calibration tool used in laser interferometer gravitational-wave observatory, Virgo, and KAGRA, and it was utilized in joint observation 3 with GEO600 in Germany in April 2020. In this paper, KAGRA implemented three key enhancements: a high-power laser, a power stabilization system, and remote beam position control. KAGRA employs a 20 W laser divided into two beams that are injected onto the mirror surface. By utilizing a high-power laser, the response of the detector at kHz frequencies can be calibrated. To independently control the power of each laser beam, an optical follower servo was installed for power stabilization. The optical path of the photon calibrator's beam positions was controlled using pico-motors, allowing for the characterization of the detector's rotation response. Additionally, a telephoto camera and quadrant photodetectors were installed to monitor beam positions, and beam position control was implemented to optimize the mirror response. In this paper, we discuss the statistical errors associated with the measurement of relative power noise. We also address systematic errors related to the power calibration model of the photon calibrator and the simulation of elastic deformation effects using finite element analysis. Ultimately, we have successfully reduced the total systematic error from the photon calibrator to 2.0%.

7.
Phys Rev Lett ; 107(24): 241801, 2011 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-22242990

RESUMEN

We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement.

9.
J Hosp Infect ; 99(2): 133-138, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29325870

RESUMEN

BACKGROUND: Antimicrobial stewardship programmes are considered essential for optimizing antimicrobial use in order to improve patient outcomes, reduce the number of adverse sequelae, prevent resistance, and ensure cost-effective therapy. AIM: To assess the efficacy and the limitations of antifungal antimicrobial stewardship programmes. METHODS: A bundle to manage infectious diseases was implemented in our hospital in October 2010. Data regarding antimicrobial use density (AUD) from April 2006 to May 2016 were collected. Trends in AUD were assessed using an interrupted time-series model for three separate periods: the pre-bundle, the bundle implementation, and the long-term follow-up periods. The primary and secondary outcomes were AUD (defined daily dose (DDD) per 1000 patient-days) of intravenous antifungals and expenditure on antifungals per fiscal year, respectively. FINDINGS: The AUD for all intravenous antifungals decreased from 26.1 in 2006 to 9.9 in 2015. Whereas the change in the trend during the pre-bundle period was not significant (slope: 0.062; 95% confidence interval (CI): -0.180 to 0.305), a significant decrease was observed in the bundle implementation period (slope: -0.535; 95% CI: -0.907 to -0.164). The trend slowed during the long-term follow-up period (slope: -0.040; 95% CI: -0.218 to 0.138). Total expenditure on antifungals decreased by 73%, from ¥52,354,411 in fiscal year 2006 to ¥14,073,099 in fiscal year 2015. CONCLUSION: The bundle significantly reduced the use of antifungals and decreased costs over time, but this effect was limited in that it had stabilized within three years.


Asunto(s)
Antifúngicos/uso terapéutico , Programas de Optimización del Uso de los Antimicrobianos/estadística & datos numéricos , Enfermedades Transmisibles/tratamiento farmacológico , Revisión de la Utilización de Medicamentos , Especialización , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Análisis de Series de Tiempo Interrumpido , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados no Aleatorios como Asunto , Paquetes de Atención al Paciente , Centros de Atención Terciaria , Tokio
10.
Bone Marrow Transplant ; 40(8): 773-8, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17700597

RESUMEN

Secondary failure of platelet recovery (SFPR), which is a delayed decline in platelet count after primary recovery following myeloablative hematopoietic SCT, is a significant problem in allogeneic SCT. However, its clinical characteristics have not been well described in autologous SCT for acute myeloid leukemia. We reviewed 11 consecutive patients who had received autologous or syngeneic SCT for acute promyelocytic leukemia. Seven of 11 patients (64%) had SFPR, which is defined as a decline in the platelet count to less than 30,000/microl for more than 7 days. The median onset of SFPR was day 36 (range, 25-51 days) and the median duration of thrombocytopenia was 13 days (range, 4-25 days). Of nine patients who received busulfan-containing preparative regimens, seven (78%) had SFPR and one had delayed primary platelet count recovery. Neither patient who received cyclophosphamide and total body irradiation as preparative regimens had SFPR. The clinical courses of SFPR were transient and self-limited. SFPR was not associated with relapse of underlying diseases, graft failure or other fatal morbidities. The unexpectedly high prevalence and the characteristics of SFPR may provide additional information on management following autologous SCT for acute myeloid leukemia.


Asunto(s)
Leucemia Promielocítica Aguda/cirugía , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Trombocitopenia/etiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Trasplante Autólogo , Trasplante Isogénico
11.
Cancer Res ; 59(18): 4542-5, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10493503

RESUMEN

The restricted expression of oncofetal fibronectin (onfFN) mRNA in thyroid papillary and anaplastic carcinomas was recently reported. In this study, we measured the copy number of onfFN mRNA in RNAs extracted from fine needle aspiration biopsies by real-time quantitative reverse transcription-PCR using thyroglobulin mRNA as an internal control. By measuring the onfFN:thyroglobulin mRNA ratio, preoperative aspirates from 31 papillary carcinomas and an anaplastic carcinoma can be distinguished from those from 5 adenomatous goiters, 5 follicular adenomas, and 4 follicular carcinomas. Thus, quantification of onfFN by real-time quantitative reverse transcription-PCR may be useful for the preoperative diagnosis of papillary and anaplastic carcinomas.


Asunto(s)
Carcinoma Papilar/patología , Carcinoma/patología , Fibronectinas/genética , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Secuencia de Bases , Biomarcadores de Tumor/genética , Biopsia con Aguja , Carcinoma/genética , Carcinoma/cirugía , Carcinoma Papilar/genética , Carcinoma Papilar/cirugía , Cartilla de ADN , Humanos , Tiroglobulina/genética , Neoplasias de la Tiroides/genética
12.
Cancer Res ; 58(21): 4913-7, 1998 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9809999

RESUMEN

Recently, the restricted expression of oncofetal fibronectin mRNA was reported in thyroid papillary and anaplastic carcinomas. In this study, by extracting RNA from the leftover cells inside the needles used for fine-needle aspiration biopsy, we establish a new method for gene diagnosis of these carcinomas without further invasiveness to the patient (aspiration biopsy-reverse transcription-PCR, ABRP). RNA was extracted from 177 fine-needle aspiration biopsies of thyroid nodules that were suspicious for malignancy, and then the gene diagnoses made by reverse transciption-PCR detection of oncofetal fibronectin mRNA were compared with cytological diagnoses. Thirty-five (94.6%) of 37 samples that were diagnosed as papillary or anaplastic carcinomas by cytological examination showed a positive result by gene diagnosis, whereas only 4 (3.7%) of 109 samples that were cytologically diagnosed negative for both carcinomas showed a positive result. Among all of the cases, 50 patients underwent surgery, and a histological diagnosis was consequently made. The sensitivity and specificity of this method were 96.9 and 100%, respectively. A combined examination using both genetic and cytological approaches may contribute to a more precise preoperative diagnosis of papillary and anaplastic carcinomas.


Asunto(s)
Antígenos de Neoplasias/genética , Carcinoma Papilar/diagnóstico , Fibronectinas/genética , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias de la Tiroides/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Femenino , Humanos , Masculino , Persona de Mediana Edad
13.
Bone Marrow Transplant ; 36(2): 115-21, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15908969

RESUMEN

To evaluate the incidence, risk factors and prognosis for solid tumors after hematopoietic stem cell transplantation (HSCT) in Japan, 809 patients who had received HSCT between 1981 and 2000 were retrospectively analyzed. In all, 19 newly diagnosed secondary cancers were observed. The risk for cancer development was 2.8 times as high as that for expected cases. The cumulative incidence ratios at 5 and 10 years were 1.9 and 4.2%, respectively. The risk was significantly elevated for buccal cavity cancer (standard incidental ratio (SIR), 44.42: 95% confidence interval (CI) 17.86-91.51), esophageal cancer (SIR, 22.36: 95% CI 6.09-57.25), and cervical cancer (SIR, 8.58: 95% CI 1.04-31.01). Of 15 patients who developed solid cancers following allografting, 12 had chronic graft-versus-host disease (GVHD), and all 10 patients with squamous cell carcinoma of the buccal cavity or esophagus had chronic GVHD. On multivariate analysis, extensive chronic GVHD and age over 45 years at the time of transplantation were associated with a higher risk for solid cancers. In all, 17 patients received therapy for secondary cancers, nine of whom are still alive and the 5-year probability of survival from the diagnosis is 42.8%. Our data suggest that early detection of secondary cancers is very important in prolonging overall survival.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Neoplasias Primarias Secundarias/epidemiología , Neoplasias/epidemiología , Adulto , Anciano , Femenino , Enfermedad Injerto contra Huésped/complicaciones , Enfermedad Injerto contra Huésped/epidemiología , Enfermedad Injerto contra Huésped/mortalidad , Humanos , Incidencia , Japón , Masculino , Persona de Mediana Edad , Neoplasias/etiología , Neoplasias/mortalidad , Neoplasias Primarias Secundarias/etiología , Neoplasias Primarias Secundarias/mortalidad , Pronóstico , Factores de Riesgo , Trasplante Homólogo
14.
Leukemia ; 14(1): 28-33, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10637473

RESUMEN

There are few molecular biologic determinants that are prognostic for patients with acute myeloid leukemia (AML). Hence, we examined whether cellular levels of the cyclin-dependent kinase inhibitor p27Kip1 in acute myeloid leukemia could be used to predict clinical outcome in AML. Using immunoblot analysis, levels of p27 were assessed in blast cells from 72 AML patients who were registered and treated by the identical chemotherapy protocol. AML cases were classified into three groups on the basis of the percentage of the expression level of p27 compared to a control cell line. AML cases exhibiting p27 expression at low, moderate, and high levels were 43, 9, and 20 cases, respectively. No significant differences in the rates of complete remission (CR) were observed among the three groups. Although the level of p27 expression was not correlated with any other possible prognostic markers, such as age, white blood cell count, chromosome abnormalities, and FAB subclasses, patients with high p27 expression had a significantly increased disease-free survival (DFS) (78% vs 19%, P = 0.004). We further examined the expression of cyclin E at the protein level in all 72 AML cases. We observed a statistically significant correlation between a high cyclin E level and a high p27 level (P < 0.005). However, we failed to find any correlation between the rates of CR or DFS and cyclin E expression. The present study reveals that levels of p27 expression can be one of the useful prognostic molecular markers for AML. Leukemia (2000) 14, 28-33.


Asunto(s)
Proteínas de Ciclo Celular , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Leucemia Mieloide/fisiopatología , Proteínas Asociadas a Microtúbulos/fisiología , Proteínas Supresoras de Tumor , Enfermedad Aguda , Adolescente , Adulto , Anciano , Biomarcadores de Tumor , Ciclina E/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patología , Proteínas Asociadas a Microtúbulos/metabolismo , Persona de Mediana Edad , Pronóstico
15.
Clin Cancer Res ; 6(10): 4091-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11051261

RESUMEN

Several genetic polymorphisms in metabolic activation or detoxification enzymes have been associated with susceptibility to therapy-related leukemia and myelodysplastic leukemia (TRLIMDS). We analyzed gene polymorphisms of NAD(P)H:quinone oxidoreductase (NQOl), glutathione S-tranferase (GST)-MI and -TI, and CYP3A4, the enzymes of which are capable of metabolizing anticancer drugs, in 58 patients with TRL/MDS and in 411 patients with de novo acute myeloid leukemia (AML). Homozygous Ser/Ser genotype of NQOl at codon 187, causing loss of function, was more frequent in the patients with TRLIMDS (14 of 58, 24.1%; OR = 2.62) than in those with de novo AML (64 of 411, 15.6%), and control (16 of 150, 10.6%; P = 0.002). Allelic frequencies of NQOJ were different between TRL/ MDS and de novo AML (P = 0.01). In GST-MJ and -Ti, the incidence of homologous deletion was similar among the three groups. The polymorphism of the 5' promoter region of CYP3A4 was not found in persons of Japanese ethnicity. These results suggest that the NQOJ polymorphism is significantly associated with the genetic risk of TRLIMDS.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Glutatión Transferasa/genética , Leucemia Mieloide Aguda/genética , Leucemia/inducido químicamente , Leucemia/genética , Oxigenasas de Función Mixta/genética , Síndromes Mielodisplásicos/inducido químicamente , Síndromes Mielodisplásicos/genética , NADH NADPH Oxidorreductasas/genética , Polimorfismo Genético , Adulto , Alelos , Codón , Citocromo P-450 CYP3A , Complejo I de Transporte de Electrón , Femenino , Eliminación de Gen , Genotipo , Humanos , Japón , Masculino , Persona de Mediana Edad , Riesgo
16.
J Med Food ; 8(3): 362-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16176148

RESUMEN

The antioxidant properties of amla extracts and their effects on the oxidative stress in streptozotocin-induced diabetes were examined in rats. Amla in the form of either the commercial enzymatic extract SunAmla (Taiyo Kagaku Co. Ltd., Yokkaichi, Japan) (20 or 40 mg/kg of body weight/day) or a polyphenol-rich fraction of ethyl acetate extract (10 or 20 mg/kg of body weight/day) was given orally for 20 days to the streptozotocin-induced diabetic rats. Amla extracts showed strong free radical scavenging activity. Amla also showed strong inhibition of the production of advanced glycosylated end products. The oral administration of amla extracts to the diabetic rats slightly improved body weight gain and also significantly alleviated various oxidative stress indices of the serum of the diabetic rats. The elevated serum levels of 5-hydroxymethylfurfural, which is a glycosylated protein that is an indicator of oxidative stress, were significantly reduced dose-dependently in the diabetic rats fed amla. Similarly, the serum level of creatinine, yet another oxidative stress parameter, was also reduced. Furthermore, thiobarbituric acid-reactive substances levels were significantly reduced with amla, indicating a reduction in lipid peroxidation. In addition, the decreased albumin levels in the diabetic rats were significantly improved with amla. Amla also significantly improved the serum adiponectin levels. These results form the scientific basis supporting the efficacy of amla for relieving the oxidative stress and improving glucose metabolism in diabetes.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Phyllanthus emblica/química , Extractos Vegetales/uso terapéutico , Adiponectina , Animales , Ácido Ascórbico/análisis , Compuestos de Bifenilo , Peso Corporal , Creatinina/sangre , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/fisiopatología , Ingestión de Líquidos , Ingestión de Alimentos , Flavonoides/análisis , Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Glicopirrolato , Péptidos y Proteínas de Señalización Intercelular/sangre , Masculino , Tamaño de los Órganos , Fenoles/análisis , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Polifenoles , Ratas , Ratas Wistar , Albúmina Sérica/análisis , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
17.
Exp Hematol ; 28(10): 1129-36, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11027831

RESUMEN

OBJECTIVE: Cytotoxic T lymphocytes (CTL) initially recognize target cells using the T-cell receptor (TCR), then strongly adhere to these cells by accessory molecules, and finally induce apoptosis by Fas ligand (FasL)/Fas or lyse by the granzyme/perforin system. We describe the development of gelatin beads carrying anti-tumor monoclonal antibody (mAb) and anti-Fas mAb mimicking the TCR and FasL, respectively. We hypothesized that these antibody-coated beads can be therapeutically utilized for the elimination of tumor cells. MATERIALS AND METHODS: We evaluated the cytotoxic activity of gelatin beads bearing CH11 (anti-Fas mAb) after incubation with several human leukemia cell lines. Cytotoxic activities were measured using colorimetric DNA fragmentation assay and lactate dehydrogenase (LDH) release assay. RESULTS: We demonstrated that the cytotoxic effects of anti-Fas mAb were markedly enhanced by fixation on gelatin beads. Microscopic examination showed that the beads attached to the target cells and induced their apoptosis. These effects were enhanced further by adding tumor-specific mAb. These in vitro properties of the beads were well reconstituted in the peritoneal cavity of mice. CONCLUSION: Although antibody-coated gelatin beads lack several important properties of natural CTL, such as differentiation, proliferation, and the functions of adhesion molecules, they mimic well the targeting and cytotoxic functions of natural CTL. Our findings suggest that antibody-carrying gelatin beads may be the first step toward the development of artificial CTL and can be applied, for example, to artificial dendritic and stroma cells for the development of novel biotherapeutic approaches.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Gelatina , Leucemia/inmunología , Microesferas , Linfocitos T Citotóxicos/inmunología , Receptor fas/inmunología , Animales , Apoptosis , Antígenos CD13/inmunología , Citotoxicidad Inmunológica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Cavidad Peritoneal , Células Tumorales Cultivadas
18.
J Clin Endocrinol Metab ; 84(3): 951-5, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10084577

RESUMEN

Fine needle aspiration Biopsy (FNAB) is commonly used to diagnose thyroid tumors. In some clinical situations, however, accurate diagnosis requires a more objective method than cytological examination alone. Medullary thyroid carcinomas (MTC) derive from C cells in the thyroid and express some specific messenger RNAs (mRNA), such as those transcribed from the RET proto-oncogene, the calcitonin gene, and the gene for carcinoembryonic antigen (CEA), which usually do not exist in normal thyroid follicular cells or thyroid tumors of follicular epithelial descent. Recently, we established a new method for the molecular diagnosis of thyroid tumors without additional invasion to the patient by extracting RNA for RT-PCR from the leftover cells inside the needles used for fine needle aspiration biopsy (Aspiration Biopsy-Reverse Transcription-Polymerase Chain Reaction, ABRP). By applying the ABRP method to the detection of RET, calcitonin, and CEA mRNAs, an accurate molecular-based diagnosis for MTC maybe established as an adjunct to cytological diagnosis. In this study, 35 aspirates were obtained at the time of surgery from thyroid tumors, including 11 MTCs. The expression of these mRNAs in the leftover cells inside the needles used for the aspiration was then examined. Transcripts from all three genes were detected in the samples from all 11 MTCs, but none of these mRNAs were detected in the other tumors or normal thyroid tissues. Furthermore, MTC was preoperatively diagnosed in three patients by ABRP detection of these mRNAs, and these diagnoses were confirmed by subsequent cytological and histopathological analyses. Thus RT-PCR detection of RET, calcitonin, and CEA mRNAs in FNABs may be an efficient molecular adjunct for diagnosing MTC.


Asunto(s)
Carcinoma Medular/diagnóstico , Proteínas de Drosophila , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias de la Tiroides/diagnóstico , Adulto , Anciano , Biopsia con Aguja , Calcitonina/genética , Antígeno Carcinoembrionario/genética , Carcinoma Medular/patología , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-ret , ARN Mensajero/genética , Proteínas Tirosina Quinasas Receptoras/genética , Neoplasias de la Tiroides/patología
19.
J Clin Endocrinol Metab ; 84(4): 1438-44, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10199792

RESUMEN

We analyzed the thyroglobulin (Tg) gene of 2 unrelated patients with congenital goiter and the Tg gene of 2 siblings with the variant type of adenomatous goiter. The clinical characteristics of the patients with congenital goiter and the variant type of adenomatous goiter were very similar, except for serum Tg levels, which were less than 15 pmol/L in the patients with congenital goiter, but 117-181 pmol/L in the patients with the variant type of adenomatous goiter (normal, 15-50 pmol/L). The tissue content of Tg in the thyroid glands of all 4 patients was reduced at 0.9-3.8% of total protein (normal, 19-40%). The missense mutation C1263R was detected in the 2 unrelated patients with congenital goiter; the pedigree study showed an autosomal recessive pattern of inheritance. In the 2 siblings with the variant type of adenomatous goiter, the missense mutation C1995S was homozygously detected. In the Tg complementary DNA of 110 normal subjects, the allelic frequencies of the C1263R and C1995S mutations were each less than 0.5%. Also in the normal subjects were detected 35 nucleotide polymorphisms, the insertion of 3 nucleotides, and 1 alternative splicing, each of which was not associated with any specific thyroid disease. From these data, the molecular mechanism of the C1263R and C1995S mutations was elucidated. We first analyzed the carbohydrate residues of C1263R Tg and C1995S Tg. Sensitivity to treatment by endoglycosidase H suggests that C1263R Tg and C1995S Tg were retained in the endoplasmic reticulum (ER). Also, the presence of endoglycosidase H-resistant Tg as well as endoglycosidase H-sensitive Tg in the patients with the variant type of adenomatous goiter suggests that a fraction of C1995S Tg was transported to the Golgi and associated with the mildly increased serum Tg levels. Native PAGE and Western blot analysis with anti-Tg antibody showed that C1263R Tg and C1995S Tg form high mol wt aggregates in the ER. Our results suggest that missense mutations that replace cysteine with either arginine or serine cause an abnormal three-dimensional structure of Tg. Such misfolded Tg polypeptides are retained in the ER as high mol wt aggregates.


Asunto(s)
Adenoma/genética , Bocio/genética , Mutación Missense , Tiroglobulina/genética , Neoplasias de la Tiroides/genética , Transporte Biológico , ADN Complementario/química , Bocio/congénito , Bocio/metabolismo , Haplotipos , Hexosaminidasas/farmacología , Humanos , Peso Molecular , Linaje , Polimorfismo Genético , Tiroglobulina/química , Tiroglobulina/metabolismo
20.
Biochem Pharmacol ; 56(2): 213-22, 1998 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9698075

RESUMEN

Fifty-one tannins and forty-one flavonoids isolated from Oriental medicinal herbs were evaluated for their antioxidant ability with a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-generating system. The results showed that tannins and certain flavonoids are potential free-radical scavengers, and that their activity against the DPPH radical is closely associated with their chemical structure. A comparison of the two classes of compounds showed that tannins have more potential than flavonoids because almost all the tannins demonstrated significant scavenging action within a low concentration range, whereas the activity of flavonoids varied distinctively among the different compounds. An increase of galloyl groups, molecular weight, and ortho-hydroxyl structure enhanced the activity of tannins, whereas the number and position of hydroxyl groups were important features for the scavenging of free radicals by flavonoids. Moreover, it appeared that when the free hydroxyl group was methoxylated or glycosylated, the inhibitory activity was obviously decreased or even abolished.


Asunto(s)
Bepridil/análogos & derivados , Flavonoides/farmacología , Picratos , Taninos/farmacología , Bepridil/antagonistas & inhibidores , Compuestos de Bifenilo , Flavonoides/química , Depuradores de Radicales Libres , Radicales Libres , Estructura Molecular , Relación Estructura-Actividad , Taninos/química
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