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1.
Epidemiol Infect ; 145(14): 2896-2911, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28826420

RESUMEN

The purpose of this study was to clarify the association between hand, foot, and mouth disease (HFMD) epidemics and meteorological conditions. We used HFMD surveillance data of all 47 prefectures in Japan from January 2000 to December 2015. Spectral analysis was performed using the maximum entropy method (MEM) for temperature-, relative humidity-, and total rainfall-dependent incidence data. Using MEM-estimated periods, long-term oscillatory trends were calculated using the least squares fitting (LSF) method. The temperature and relative humidity thresholds of HFMD data were estimated from the LSF curves. The average temperature data indicated a lower threshold at 12 °C and a higher threshold at 30 °C for risk of HFMD infection. Maximum and minimum temperature data indicated a lower threshold at 6 °C and a higher threshold at 35 °C, suggesting a need for HFMD control measures at temperatures between 6 and 35 °C. Based on our findings, we recommend the use of maximum and minimum temperatures rather than the average temperature, to estimate the temperature threshold of HFMD infections. The results obtained might aid in the prediction of epidemics and preparation for the effect of climatic changes on HFMD epidemiology.


Asunto(s)
Epidemias , Enfermedad de Boca, Mano y Pie/epidemiología , Humedad , Lluvia , Temperatura , Niño , Preescolar , Enfermedad de Boca, Mano y Pie/virología , Humanos , Incidencia , Lactante , Recién Nacido , Japón/epidemiología , Análisis de los Mínimos Cuadrados , Estaciones del Año
2.
Osteoporos Int ; 27(4): 1441-1450, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26525045

RESUMEN

UNLABELLED: Once-weekly 56.5-µg teriparatide treatment was significantly associated with the increase in lumbar spine bone mineral density at 48 weeks among hemodialysis patients with hypoparathyroidism and low bone mass; however, discontinuation of treatment because of adverse events was frequently observed. Careful monitoring for adverse events should be required. INTRODUCTION: Once-weekly 56.5-µg teriparatide is reportedly effective for treating osteoporotic patients without renal insufficiency. However, little is known about the efficacy and safety of once-weekly teriparatide in hemodialysis patients. METHODS: We conducted a 48-week prospective, observational cohort study including 22 hemodialysis patients aged 20 years or older with hypoparathyroidism and low bone mass who received once-weekly teriparatide at 56.5 µg at a tertiary care hospital between January 2013 and January 2015. Primary outcomes were within-subject percent changes of bone mineral density (BMD) at the lumbar spine, femoral neck, and distal one-third radius at 24 and 48 weeks. Secondary outcomes included percent changes of serum bone turnover markers (osteocalcin, bone-specific alkaline phosphatase (BAP), N-terminal propeptide of procollagen type 1 (P1NP), and tartrate-resistant acid phosphatase 5b (TRAP-5b)). Adverse events were evaluated. RESULTS: The BMD increased at the lumbar spine by 3.3 ± 1.9 % (mean ± SEM) and 3.0 ± 1.8 % at 24 and 48 weeks but not in the femoral neck and distal one-third radius. Serum osteocalcin, BAP, and P1NP increased significantly at 4 weeks, maintaining higher concentrations up to 48 weeks, although TRAP-5b decreased gradually during treatment. The baseline BAP was significantly associated with the 48-week percent change in lumbar spine BMD. Transient hypotension was the most common adverse event. Ten patients discontinued treatment because of adverse events. CONCLUSIONS: Once-weekly teriparatide was associated with increased lumbar spine BMD in hemodialysis patients with hypoparathyroidism and low bone mass. Careful monitoring should be required for treatment of such patients.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Hipoparatiroidismo/complicaciones , Fallo Renal Crónico/complicaciones , Osteoporosis/tratamiento farmacológico , Diálisis Renal , Teriparatido/administración & dosificación , Anciano , Anciano de 80 o más Años , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/efectos adversos , Conservadores de la Densidad Ósea/uso terapéutico , Esquema de Medicación , Femenino , Cuello Femoral/fisiopatología , Humanos , Hipoparatiroidismo/fisiopatología , Fallo Renal Crónico/fisiopatología , Fallo Renal Crónico/terapia , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Osteoporosis/fisiopatología , Estudios Prospectivos , Radio (Anatomía)/fisiopatología , Teriparatido/efectos adversos , Teriparatido/uso terapéutico
3.
Diabet Med ; 32(4): 546-55, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25400024

RESUMEN

AIMS: To investigate the relationship between the progression of anaemia and renal pathological findings in patients with diabetic nephropathy. METHODS: A total of 223 patients with diabetes underwent renal biopsy from 1985 to 2010 and were confirmed to have pure diabetic nephropathy according to the recent classification, of whom 113 (baseline haemoglobin ≥ 11 g/dl) were enrolled in the study. Linear regression analysis was used to estimate the changes in haemoglobin levels during the follow-up period. RESULTS: In a multivariate model adjusted for clinical and histopathological variables, higher interstitial fibrosis and tubular atrophy scores were more strongly associated with a decrease in haemoglobin levels than were lower scores. Compared with an interstitial fibrosis and tubular atrophy score of 0, the standardized coefficients for interstitial fibrosis and tubular atrophy scores of 1, 2 and 3 were 0.20 (95% CI -0.31 to 0.93), 0.34 (95% CI -0.22 to 1.34) and 0.47 (95% CI 0.07 to 1.96), respectively, whereas a higher glomerular class, a higher vascular lesion score and the presence of exudative lesions were not strongly correlated with the decrease in haemoglobin. CONCLUSIONS: Tubulointerstitial lesions that are more advanced are significantly associated with the progression of anaemia in patients with diabetic nephropathy after adjustment for numerous covariates. This finding suggests that tubulointerstitial lesions may be a useful prognostic indicator for anaemia in patients with diabetic nephropathy, and that decreased erythropoietin production attributable to the progression of tubulointerstitial lesions is a major cause of anaemia in these patients.


Asunto(s)
Anemia/patología , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 2/patología , Nefropatías Diabéticas/patología , Riñón/patología , Atrofia/patología , Biopsia , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Nefropatías Diabéticas/fisiopatología , Progresión de la Enfermedad , Femenino , Fibrosis , Tasa de Filtración Glomerular/fisiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Eur J Clin Microbiol Infect Dis ; 34(7): 1369-79, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25851811

RESUMEN

Cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD). Lipid-soluble antibiotics like fluoroquinolones show good penetration into cysts and are recommended for cyst infection, but causative microorganisms are often resistant to these agents. This study investigated the profile of the microorganisms causing cyst infection in ADPKD, their susceptibility to lipid-soluble antibiotics, and clinical outcomes. This retrospective study reviewed all ADPKD patients admitted to Toranomon Hospital with a diagnosis of cyst infection from January 2004 to March 2014. All patients who underwent cyst drainage and had positive cyst fluid cultures were enrolled. Patients with positive blood cultures who satisfied our criteria for cyst infection or probable infection were also enrolled. There were 99 episodes with positive cyst fluid cultures and 93 episodes with positive blood cultures. The majority of patients were on dialysis. The death rate was high when infection was caused by multiple microorganisms or when there were multiple infected cysts. Gram-negative bacteria accounted for 74-79 % of the isolates in all groups, except for patients with positive hepatic cyst fluid cultures. The susceptibility of Escherichia coli to fluoroquinolones was very low in patients with hepatic cyst infection, especially those with frequent episodes and those with hepatomegaly. Fungi were detected in two episodes. Fluoroquinolone-resistant microorganisms showed a high prevalence in cyst infection. It is important to identify causative microorganisms to avoid the overuse of fluoroquinolones and to improve the outcome of cyst infection in ADPKD.


Asunto(s)
Infecciones/etiología , Riñón Poliquístico Autosómico Dominante/complicaciones , Anciano , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Microbiana , Femenino , Bacterias Gramnegativas/aislamiento & purificación , Humanos , Infecciones/diagnóstico , Infecciones/tratamiento farmacológico , Infecciones/microbiología , Infecciones/cirugía , Pruebas de Función Renal , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Riñón Poliquístico Autosómico Dominante/fisiopatología , Riñón Poliquístico Autosómico Dominante/terapia
5.
Epidemiol Infect ; 143(12): 2666-78, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25586860

RESUMEN

Annual periodicities of reported chickenpox cases have been observed in several countries. Of these, Japan has reported a two-peaked, bimodal annual cycle of reported chickenpox cases. This study investigated the possible underlying association of the bimodal cycle observed in the surveillance data of reported chickenpox cases with the meteorological factors of temperature, relative humidity and rainfall. A time-series analysis consisting of the maximum entropy method spectral analysis and the least squares method was applied to the chickenpox data and meteorological data of 47 prefectures in Japan. In all of the power spectral densities for the 47 prefectures, the spectral lines were observed at the frequency positions corresponding to the 1-year and 6-month cycles. The optimum least squares fitting (LSF) curves calculated with the 1-year and 6-month cycles explained the underlying variation of the chickenpox data. The LSF curves reproduced the bimodal and unimodal cycles that were clearly observed in northern and southern Japan, respectively. The data suggest that the second peaks in the bimodal cycles in the reported chickenpox cases in Japan occurred at a temperature of approximately 8·5 °C.


Asunto(s)
Varicela/epidemiología , Temperatura , Distribución por Edad , Niño , Preescolar , Humanos , Humedad , Incidencia , Lactante , Recién Nacido , Japón/epidemiología , Análisis de los Mínimos Cuadrados , Lluvia , Estaciones del Año , Factores de Tiempo
6.
Epidemiol Infect ; 142(10): 2036-48, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24331081

RESUMEN

We investigated the seasonality of tuberculosis (TB) in Wuhan, China, to evaluate the increased risk of disease transmission during each season and to develop an effective TB control strategy. We applied spectral analysis to the weekly prevalence data of sputum smear positive (SSP) and sputum smear negative (SSN) pulmonary TB reported from 2006 to 2010. Cases of both SSP and SSN feature 1·0- and 0·5-year periodic modes. The least squares method was used to fit curves to the two periodic modes for SSP and SSN data. The curves demonstrated dominant peaks in spring similar to cases reported previously for other locations. Notably for SSP, dominant peaks were also observed in summer. The spring peaks of SSP and SSN were explained in terms of poorly ventilated and humid rooms and vitamin D deficiency. For the summer peaks of SSP, summer influenza epidemics in Wuhan may contribute to the increase in TB prevalence.


Asunto(s)
Gripe Humana/epidemiología , Estaciones del Año , Tuberculosis Pulmonar/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , China/epidemiología , Coinfección/epidemiología , Femenino , Humanos , Humedad , Lactante , Masculino , Persona de Mediana Edad , Distribución por Sexo , Análisis Espacio-Temporal , Esputo/microbiología , Tuberculosis Pulmonar/transmisión , Ventilación , Deficiencia de Vitamina D/epidemiología , Adulto Joven
7.
Epidemiol Infect ; 139(2): 257-64, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20478086

RESUMEN

Measles is regarded as a disease that can be eliminated by vaccination; however, disease epidemics still occur in Wuhan, China. This study explored the effect of measles control programmes on the periodic structure of disease epidemics in Wuhan. The monthly reported measles incidence from 1953 to 2008 was divided into pre-vaccine range (1953-1965) and post-vaccine range (1966-2008). For the incidence in each range, spectral analysis was conducted and power spectral density (PSD) was obtained. In PSD for the pre-vaccine range, the most dominant spectral line was observed at a 2·0-year period, as in the case of Japan. It was confirmed that spectral lines of periodic modes longer than a 1-year cycle of the incidence rates behave in response to the introduction of measles control programmes. The investigation of periodic structures of measles epidemics will contribute to effective measles control programmes in Wuhan.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Epidemias/prevención & control , Sarampión/epidemiología , Sarampión/prevención & control , China/epidemiología , Humanos , Incidencia , Factores de Tiempo
8.
Public Health ; 125(10): 734-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21906764

RESUMEN

OBJECTIVE: Tuberculosis and sarcoidosis are chronic granulomatous diseases. Clinical, pathologic and immunologic aspects are similar although different. The authors were interested to highlight possible epidemiological similarities of these two granulomatous diseases. The objective of this study was to evaluate incidence rate as well as age, sex and geographic distribution of sarcoidosis in South Croatia and to compare it with these epidemiological characteristics of tuberculosis. STUDY DESIGN: Retrospective. METHODS: The study was including ten years follow up period (1997-2006), and was performed in Split-Dalmatia County, Croatia. All data were collected retrospectively and analyzed using Statistica 7 programme. RESULTS: The mean annual incidence of sarcoidosis was 3.3/100,000 inhabitants with a mean of 15,6 cases per year. Woman accounted for 61% of all sarcoidosis cases. The mean sarcoidosis patient age was 44.94 ± 11.85 years. The peak age group was 40-49 years (31%). Significant difference according to incidence rate on the islands comparing to the rates on the coast and the mainland was observed (P = 0.003). The mean sarcoidosis mortality rate was 1.2/100,000. Statistically significant differences between sarcoidosis and tuberculosis were observed according the higher number of tuberculosis patients (P < 0.000), among males (P < 0.000), and females, too (P < 0.000) as well as in mortality rates (P = 0.401). Significantly more patients had tuberculosis on the mainland (P < 0.000) and on the coast (P < 0.000), but not in the islands (P = 0.260). CONCLUSIONS: The results from this study showed dissimilarities in classic epidemiological patterns between sarcoidosis and tuberculosis, incidence rates, as well as sex and geographic distribution. Our findings resulted from this study might be starting point for the future epidemiological, genetic, and immunological studies.


Asunto(s)
Sarcoidosis/epidemiología , Tuberculosis/epidemiología , Adulto , Factores de Edad , Croacia/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores Sexuales
9.
Nucleic Acids Res ; 28(24): E107, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11121494

RESUMEN

A set of fluorescently-labeled DNA probes that hybridize with the target RNA and produce fluorescence resonance energy transfer (FRET) signals can be utilized for the detection of specific RNA. We have developed probe sets to detect and discriminate single-strand RNA molecules of plant viral genome, and sought a method to improve the FRET signals to handle in vivo applications. Consequently, we found that a double-labeled donor probe labeled with Bodipy dye yielded a remarkable increase in fluorescence intensity compared to a single-labeled donor probe used in an ordinary FRET. This double-labeled donor system can be easily applied to improve various FRET probes since the dependence upon sequence and label position in enhancement is not as strict. Furthermore this method could be applied to other nucleic acid substances, such as oligo RNA and phosphorothioate oligonucleotides (S-oligos) to enhance FRET signal. Although the double-labeled donor probes labeled with a variety of fluorophores had unexpected properties (strange UV-visible absorption spectra, decrease of intensity and decay of donor fluorescence) compared with single-labeled ones, they had no relation to FRET enhancement. This signal amplification mechanism cannot be explained simply based on our current results and knowledge of FRET. Yet it is possible to utilize this double-labeled donor system in various applications of FRET as a simple signal-enhancement method.


Asunto(s)
Sondas de ADN/metabolismo , Colorantes Fluorescentes/metabolismo , Hibridación de Ácido Nucleico , ARN Viral/metabolismo , Tobamovirus/genética , Sondas de ADN/genética , Oligodesoxirribonucleótidos/genética , Oligodesoxirribonucleótidos/metabolismo , ARN Viral/genética , Sensibilidad y Especificidad , Soluciones , Espectrometría de Fluorescencia
10.
Cancer Res ; 50(19): 6199-202, 1990 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-2400985

RESUMEN

We examined the effects of heat treatment on tumor cells and antitumor effector cells in order to investigate the combined effects of hyperthermia and immunotherapy including adoptive immunotherapy. Plasmacytoma MOPC104E syngeneic to BALB/c mice was used as the tumor cell line, while fresh spleen cells immunized to MOPC104E (IM-FSC) and interleukin-2-cultured lymphocytes induced in vitro from IM-FSC (CL) were used as the effector cells. Tumor cells or effector cells were heat-treated in a water bath at 42 degrees C for 30 or 60 min. Tumor cells heat-treated at 42 degrees C for 30 min grew temporarily and then regressed in the tumor transfer test, whereas untreated tumor cells showed no regression under any conditions. Furthermore, fresh spleen cells of mice inoculated with heat-treated tumor cells from regressed tumors showed marked tumor-neutralizing activity. The antitumor effects of CL were markedly inhibited by heat treatment according to the results of the tumor-neutralizing test and the 51Cr release assay, whereas heat treatment had little influence on the antitumor activity of IM-FSC. However, the neutralizing activity of effectors and the killing activity of CL against heat-treated tumor cells were both markedly augmented, since the susceptibility of the tumor cells to the antitumor effector cells was augmented by heat treatment. These results suggest that heat treatment of tumor cells augments the antitumor effects of IM-FSC and CL, hence we speculate that hyperthermia augments the effects of immunotherapy including adoptive immunotherapy.


Asunto(s)
Calor/uso terapéutico , Inmunoterapia/métodos , Linfocitos/inmunología , Plasmacitoma/terapia , Animales , Terapia Combinada , Masculino , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Plasmacitoma/patología , Bazo/citología , Bazo/inmunología , Temperatura , Factores de Tiempo , Células Tumorales Cultivadas
11.
Trends Microbiol ; 2(1): 29-31, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8162434

RESUMEN

Molecular genetic studies of RNA virus host range suggest that successful systemic infection requires many or all viral genes to have some degree of specific adaptation to the host. In some cases, accommodation to the host appears to be required for viral gene products to fulfil their primary functions in viral multiplication, while in other cases, adaptation seems to be required to avoid eliciting host defenses.


Asunto(s)
Virus de Plantas/fisiología , Virus ARN/fisiología , Adaptación Fisiológica , Genes Virales , Virus de Plantas/genética , Plantas/microbiología , Virus ARN/genética
12.
Clin Cancer Res ; 4(6): 1475-82, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9626465

RESUMEN

It is difficult to determine the prognosis of patients with hepatocellular carcinoma (HCC). Assessment of the clinicopathological and biological malignancy of HCC may help in determining treatment strategies and predicting outcome. The tumor DNA content, p53 protein expression, proliferating cell nuclear antigen labeling index, and argyrophilic proteins of nuclear organizer regions were used as markers of biological malignancy. A correlation between these biological parameters and clinicopathological factors was sought. DNA aneuploidy was observed in 31 of 80 tumors (38.8%). Aneuploidy increased as differentiation decreased. The overall survival rate of patients with aneuploid tumors was significantly poorer than that of patients with diploid tumors. p53 overexpression was observed in 18 of 80 tumors (22.5%). The incidence of p53 positivity increased significantly with increasing tumor size and poorer differentiation. The overall survival rate of p53-positive patients was significantly worse than that of p53-negative patients. The proliferating cell nuclear antigen labeling index and the mean number of argyrophilic proteins of nuclear organizer regions were higher in more poorly differentiated lesions. We conclude that DNA ploidy and p53 expression are useful prognostic indicators in HCC. Cell proliferation increases as HCC progresses. With progression, tumors tend to become more poorly differentiated.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , ADN de Neoplasias/análisis , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Adulto , Factores de Edad , Anciano , Aneuploidia , Biopsia , Carcinoma Hepatocelular/mortalidad , Diferenciación Celular , Diploidia , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Índice Mitótico , Análisis Multivariante , Región Organizadora del Nucléolo/patología , Valor Predictivo de las Pruebas , Pronóstico , Antígeno Nuclear de Célula en Proliferación/análisis , Análisis de Regresión , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Proteína p53 Supresora de Tumor/análisis
13.
Mol Plant Microbe Interact ; 13(4): 374-83, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10755300

RESUMEN

The infection process of Colletotrichum lagenarium, the causal agent of cucumber anthracnose disease, involves several key steps: germination; formation of melanized appressoria; appressorial penetration; and subsequent invasive growth in host plants. Here we report that the C. lagenarium CMK1 gene encoding a mitogen-activated protein (MAP) kinase plays a central role in these infection steps. CMK1 can complement appressorium formation of the Pmk1 MAP kinase mutant of Magnaporthe grisea. Deletion of CMK1 causes reduction of conidiation and complete lack of pathogenicity to the host plant. Surprisingly, in contrast to M. grisea pmk1 mutants, conidia of cmk1 mutants fail to germinate on both host plant and glass surfaces, demonstrating that the CMK1 MAP kinase regulates conidial germination. However, addition of yeast extract rescues germination, indicating the presence of a CMK1-independent pathway for regulation of conidial germination. Germinating conidia of cmk1 mutants fail to form appressoria and the mutants are unable to grow invasively in the host plant. This strongly suggests that MAP kinase signaling pathways have general significance for infection structure formation and pathogenic growth in phytopathogenic fungi. Furthermore, three melanin genes show no or slight expression in the cmk1 mutant when conidia fail to germinate, suggesting that CMK1 plays a role in gene expression required for appressorial melanization.


Asunto(s)
Colletotrichum/genética , Proteínas Fúngicas , Proteínas Quinasas Activadas por Mitógenos/genética , Enfermedades de las Plantas/microbiología , Plantas/microbiología , Secuencia de Aminoácidos , Colletotrichum/crecimiento & desarrollo , Colletotrichum/patogenicidad , Prueba de Complementación Genética , Proteínas Quinasas Activadas por Mitógenos/aislamiento & purificación , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Esporas Fúngicas/citología , Esporas Fúngicas/crecimiento & desarrollo
14.
Mol Plant Microbe Interact ; 13(11): 1195-203, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11059486

RESUMEN

Previously, we reported that CCMV(B3a), a hybrid of bromovirus Cowpea chlorotic mottle virus (CCMV) with the 3a cell-to-cell movement protein (MP) gene replaced by that of cowpea-nonadapted bromovirus Brome mosaic virus (BMV), can form small infection foci in inoculated cowpea leaves, but that expansion of the foci stops between 1 and 2 days postinoculation. To determine whether the lack of systemic movement of CCMV(B3a) is due to restriction of local spread at specific leaf tissue interfaces, we conducted more detailed analyses of infection in inoculated leaves. Tissue-printing and leaf press-blotting analyses revealed that CCMV(B3a) was confined to the inoculated cowpea leaves and exhibited constrained movement into leaf veins. Immunocytochemical analyses to examine the infected cell types in inoculated leaves indicated that CCMV(B3a) was able to reach the bundle sheath cells through the mesophyll cells and successfully infected the phloem cells of 50% of the examined veins. Thus, these data demonstrate that the lack of long-distance movement of CCMV(B3a) is not due to an inability to reach the vasculature, but results from failure of the virus to move through the vascular system of cowpea plants. Further, a previously identified 3a coding change (A776C), which is required for CCMV(B3a) systemic infection of cowpea plants, suppressed formation of reddish spots, mediated faster spread of infection, and enabled the virus to move into the veins of inoculated cowpea leaves. From these data, and the fact that CCMV(B3a) directs systemic infection in Nicotiana benthamiana, a permissive systemic host for both BMV and CCMV, we conclude that the bromovirus 3a MP engages in multiple activities that contribute substantially to host-specific long-distance movement through the phloem.


Asunto(s)
Bromovirus/metabolismo , Fabaceae/virología , Hojas de la Planta/virología , Plantas Medicinales , Proteínas Virales/metabolismo , Transporte Biológico , Proteínas de Movimiento Viral en Plantas , Especificidad de la Especie
15.
Gene ; 36(3): 363-7, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3000888

RESUMEN

A new restriction endonuclease, EcoO109, has been isolated from Escherichia coli H709c by polyethyleneimine (PEI) precipitation, DEAE-cellulose chromatography and heparin agarose chromatography. The yield was high, more than 3000 units/g of wet cells. The EcoO109 endonuclease recognizes and cleaves a nucleotide sequence of (formula: see text), in the presence of 10 mM Mg2+. The enzyme will be useful for structural analysis and molecular cloning of DNA because of the stability, high yield and easy handling of the producer strain.


Asunto(s)
Enzimas de Restricción del ADN/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II , Escherichia coli/enzimología , Secuencia de Bases , Enzimas de Restricción del ADN/aislamiento & purificación , Plásmidos , Especificidad por Sustrato
16.
Gene ; 33(3): 357-61, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2989097

RESUMEN

A new restriction endonuclease, StyI, free of contaminating nuclease activities, has been isolated from Escherichia coli carrying the hsd+ miniplasmid of Salmonella typhi origin. In the presence of 10 mM Mg2+, it recognizes and cleaves a hexanucleotide sequence of 5'-C decreases C(AT)(AT)GG. The advantages of the StyI endonuclease include its stability, high yield (more than 2 X 10(3) units/g of wet cells), easy handling of producer cells, and the ability to recognize new sequences, CCAAGG and CCTTGG.


Asunto(s)
Enzimas de Restricción del ADN/aislamiento & purificación , Desoxirribonucleasas de Localización Especificada Tipo II , Escherichia coli/genética , Plásmidos , Salmonella typhi/genética , Bacteriófago lambda/genética , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , ADN Viral/genética , Escherichia coli/enzimología , Salmonella typhi/enzimología , Virus 40 de los Simios/genética
17.
Gene ; 30(1-3): 79-85, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6096226

RESUMEN

A restriction endonuclease designated EcoVIII, an isoschizomer of HindIII, was isolated from Escherichia coli E1585-68 and purified by dextran-polyethylene glycol (DPG) phase partition, ammonium sulfate precipitation, phospho- and DEAE-cellulose chromatography, and hydroxylapatite chromatography. The purified EcoVIII was stable during the purification procedure and its high specific activity required 10 mM Mg2+. Unlike HindIII, EcoVIII exhibited a high specific activity even at low pH (pH 6.3) and showed the highest activity at 48 degrees C. Transformation of purified plasmid DNA from E. coli E1585-68 into K-12 indicated that the EcoVIII gene was carried on a multicopy 4.4-kb miniplasmid. EcoVIII seems to be preferable to HindIII for its production and use because of easier handling of producer cells and a wider range of activity.


Asunto(s)
Enzimas de Restricción del ADN/aislamiento & purificación , Escherichia coli/enzimología , Secuencia de Bases , Desoxirribonucleasa HindIII , Escherichia coli/genética , Plásmidos , Especificidad por Sustrato
18.
Gene ; 129(1): 83-6, 1993 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-8335263

RESUMEN

A restriction endonuclease, designated StyD4I, a neoschizomer of ScrFI, has been isolated from Escherichia coli K-12 carrying a small multicopy host specificity for DNA (Hsd) plasmid of Salmonella typhi D4 origin. In the presence of 10 mM Mg2+, StyD4I cleaves the sequence 5'-/CCNGG-3' and generates a 5-nucleotide cohesive end. StyD4I should be useful for recombinant DNA technology, because of the stability and ease in handling the producer cells.


Asunto(s)
Desoxirribonucleasas de Localización Especificada Tipo II/aislamiento & purificación , Salmonella typhi/enzimología , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Escherichia coli , Plásmidos , Especificidad por Sustrato
19.
Gene ; 87(1): 119-22, 1990 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2139620

RESUMEN

A new restriction endonuclease (ENase), PshAI, has been isolated from Plesiomonas shigelloides 319-73, an organism that causes food poisoning in humans. The enzyme was stable and produced a yield of 410 units/g of cells. In the presence of 10 mM MgCl2, PshAI recognizes and cleaves the nucleotide sequence 5'-GACNN/NNGTC, producing blunt ends. PshAI will be useful for structural analysis and molecular cloning of DNA, because no ENases recognizing sequence GACNNNNGTC have been previously described.


Asunto(s)
Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Bacterias Gramnegativas/enzimología , Bacteriófago lambda/genética , Secuencia de Bases , ADN Viral/genética , Desoxirribonucleasas de Localización Especificada Tipo II/aislamiento & purificación , Escherichia coli/genética , Bacterias Gramnegativas/genética , Datos de Secuencia Molecular , Plásmidos , Especificidad de la Especie , Especificidad por Sustrato
20.
Gene ; 117(1): 103-6, 1992 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-1644299

RESUMEN

Six restriction endonucleases (ENases), classified into four different specificities, were found in a screen among 68 reference strains of Vibrio parahaemolyticus of human origin. Five of these ENases are isoschizomers of well-known ENases, while the remaining one, designated VpaK32I, is a novel and highly efficient class-IIS ENase with the hepatanucleotide recognition site, 5'-GCTCTTC(1/4)-3'.


Asunto(s)
Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Vibrio parahaemolyticus/enzimología , Secuencia de Bases , ADN Bacteriano/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Especificidad por Sustrato , Vibriosis/microbiología , Vibrio parahaemolyticus/aislamiento & purificación
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