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1.
Prog Urol ; 30(6): 322-331, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32279953

RESUMEN

OBJECTIVE: Despite optimal treatment, patients affected by non-muscle invasive bladder cancer (NMIBC) suffer from high risk of recurrence and progression. Intravescical device assisted therapies such as radiofrequency induced thermochemotherapeutic effect (RITE) and electromotive drug administration (EMDA) have shown promising effect in enhancing the effect of intravescical chemotherapies. The aim of the study was to assess clinical outcomes of these two devices in non-muscle invasive bladder cancer. METHODS: A systematic literature review was performed in December 2019 using the Medline, Embase, and Web of Science databases. Only articles published in the last 10 years were considered (2009-2019). The articles were selected using the following keywords association: "bladder cancer" AND "EMDA' AND "synergo" AND "hyperchemotherapy" AND "electromotive drug administration", AND "radiofrequency induced thermochemotherapeutic" AND "RITE". RESULTS: We found 16 studies published in the last ten years regarding the efficacy of RITE (12 studies) and EMDA (4 studies) in the treatment of NMIBC. Both RITE and EMDA showed promising results in the treatment of intermediate and high risk NMIBC as well as in patients affected by recurrent BCa after BCG failure. In high-risk BCG naïve NMIBC patients treated with EMDA recurrence and progression rates were 68% and 95%, respectively. Considering RITE, recurrence and progression range rates were 43%-88% and 62%-97%, respectively. Discordance results were reported regarding its effect on patients with carcinoma in situ. However, only few studies could be compared since differences exist regarding inclusion criteria with high patients' heterogeneity. Considering recurrence after BCG, recurrence and progression range rates were 29%-29.2% and 62%-83% for RITE and 25% and 75% for EMDA, respectively. CONCLUSION: Delivery of intravescical hyperthermia seems to enhance the normal effect of intravescical chemotherapy instillation. Although prospective trials supported its effect on both BCG naïve and BCG failure patients, data are urgently required to validate these findings and to understand its effect on patients with carcinoma in situ. LEVEL OF PROOF: 3.


Asunto(s)
Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Administración Intravesical , Quimioterapia/instrumentación , Humanos , Invasividad Neoplásica , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/patología
2.
Clin Exp Immunol ; 184(2): 257-63, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26703090

RESUMEN

The systemic inflammatory response is a challenge in the management of paediatric patients undergoing cardiac surgery. Although multi-factorial, a contribution by the lectin pathway of complement activation has been postulated. We therefore investigated the changes in serum levels of mannose binding lectin (MBL) and activities of MBL-MBL-associated serine protease (MASP)-1 and MBL-MASP-2 complexes immediately before and during surgery, throughout the first postoperative day and at discharge from the hospital. These changes were analysed in relation to postoperative complications. Blood samples were obtained from 185 children with congenital heart disease undergoing surgical correction with the use of cardiopulmonary bypass: preoperatively (MBL-1), 15 min after initiation of cardiopulmonary bypass (CPB) (MBL-E), 30 min (MBL-2), 4 h (MBL-3), 12 h (MBL-4) and 24 h (MBL-5) post-CPB and at discharge from hospital (MBL-K). Alterations in serum MBL levels were calculated as a ratio of its serum level at subsequent time-points (MBL-2, -3, -4, -5) to the preoperative (MBL-1) value. Decreases in MBL and MBL-MASP complexes were observed in all samples, correlating with a decrease in C4 and increase in C4a, confirming activation of the lectin pathway. Changes in MBL levels between children with an uncomplicated postoperative course and those suffering from infection or low cardiac output syndrome did not differ significantly, but significant differences were observed between the SIRS and non-SIRS groups. Paediatric cardiac surgery with the use of cardiopulmonary bypass activates the complement system via the lectin pathway and the latter contributes to the development of the post-bypass systemic inflammatory response.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Puente Cardiopulmonar/efectos adversos , Lectina de Unión a Manosa de la Vía del Complemento/inmunología , Lectina de Unión a Manosa/sangre , Complicaciones Posoperatorias/inmunología , Síndrome de Respuesta Inflamatoria Sistémica/inmunología , Adolescente , Niño , Preescolar , Activación de Complemento/inmunología , Complemento C4a/metabolismo , Complemento C5a/metabolismo , Femenino , Humanos , Lactante , Masculino , Lectina de Unión a Manosa/metabolismo , Serina Proteasas Asociadas a la Proteína de Unión a la Manosa/metabolismo
3.
Int J Immunogenet ; 42(6): 453-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26385254

RESUMEN

Serum ficolin-2 was measured in multiple (2-27) samples from 68 paediatric sepsis patients. Fourteen individuals (21%) gave values that included a change in status from 'normal' to 'insufficient' or vice versa. Therefore, if possible, ficolin-2 concentration should be determined in samples obtained when a disease is inactive.


Asunto(s)
Lectinas/sangre , Biomarcadores , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Reproducibilidad de los Resultados , Sepsis/sangre , Sepsis/diagnóstico , Sepsis/genética , Ficolinas
4.
Eur Urol Open Sci ; 42: 1-8, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35911084

RESUMEN

Background: Standardized methods for reporting surgical quality have been described for all the major urological procedures apart from radical nephroureterectomy (RNU). Objective: To propose a tetrafecta criterion for assessing the quality of RNU based on a consensus panel within the Young Association of Urology (YAU) Urothelial Group, and to test the impact of this tetrafecta in a multicenter, large contemporary cohort of patients treated with RNU for upper tract urothelial carcinoma (UTUC). Design setting and participants: This was a retrospective analysis of 1765 patients with UTUC treated between 2000 and 2021. Outcome measurements and statistical analysis: We interviewed the YAU Urothelial Group to propose and score a list of items to be included in the "RNU-fecta." A ranking was generated for the criteria with the highest sum score. These criteria were applied to a large multicenter cohort of patients. Kaplan-Meier curves were built to evaluate differences in overall survival (OS) rates between groups, and a multivariable logistic regression model was used to find the predictors of achieving the RNU tetrafecta. Results and limitations: The criteria with the highest score included three surgical items such as negative soft tissue surgical margins, bladder cuff excision, lymph node dissection according to guideline recommendations, and one oncological item defined by the absence of any recurrence in ≤12 mo. These items formed the RNU tetrafecta. Within a median follow-up of 30 mo, 52.6% of patients achieved the RNU tetrafecta. The 5-yr OS rates were significantly higher for patients achieving tetrafecta than for their counterparts (76% vs 51%). Younger age, lower body mass index, and robotic approach were found to be independent predictors of tetrafecta achievement. Conversely, a higher Eastern Cooperative Oncology Group score, higher clinical stage, and bladder cancer history were inversely associated with tetrafecta. Conclusions: Herein, we present a "tetrafecta" composite endpoint that may serve as a potential tool to assess the overall quality of the RNU procedure. Pending external validation, this tool could allow a comparison between surgical series and may be useful for assessing the learning curve of the procedure as well as for evaluating the impact of new technologies in the field. Patient summary: In this study, a tetrafecta criterion was developed for assessing the surgical quality of radical nephroureterectomy in patients with upper tract urothelial carcinoma. Patients who achieved tetrafecta had higher 5-yr overall survival rates than those who did not.

5.
Actas Urol Esp (Engl Ed) ; 43(8): 445-451, 2019 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31155372

RESUMEN

INTRODUCTION AND OBJECTIVES: Various studies tried to validate Club Urológico Español de Tratamiento Oncológico (CUETO) tables, yet, none of this papers focused on the high and very high risk bladder cancers. The aim of the study was to externally validate the CUETO model for predicting disease recurrence and progression in group of T1G3 tumors treated with BCG immunotherapy. PATIENTS OR MATERIALS AND METHODS: Data from 414 patients with primary T1G3 bladder cancer were analysed. To evaluate the model discrimination, Cox proportional hazard regression models were created and concordance indexes were calculated. RESULTS: The median follow-up was 68 months. The recurrence was observed in 212 (51.2%) and 64 patients (15.5%) experienced the recurrence more than once during the study follow-up. Progression of the cancer was observed in 106 patients (25.6%). Radical cystectomy was performed in 115 patients (27.8%) and there were 64 (15.5%) cancer specific deaths. For recurrence and progression probability, the concordance index of the CUETO models was 0.633 and 0.697 respectively. CUETO tables underestimated significantly the risk of recurrence and marginally the risk of progression in the first year of observation. For 5 years of observation, the trend for the recurrence was much less clear. On the contrary, there was slight overestimation in the risk of progression. The study is limited by retrospective nature. CONCLUSIONS: It was shown that the CUETO risk tables exhibit a fair discrimination for both disease recurrence and progression in T1G3 patients treated with BCG. CUETO scoring model underestimates the risk of tumor recurrence, but predicts well risk of progression.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Vacuna BCG/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico , Modelos Estadísticos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Anciano , Carcinoma de Células Transicionales/epidemiología , Carcinoma de Células Transicionales/patología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/epidemiología , Neoplasias de la Vejiga Urinaria/patología
6.
Actas Urol Esp (Engl Ed) ; 43(9): 467-473, 2019 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31272800

RESUMEN

INTRODUCTION AND OBJECTIVES: The aim of this study was to analyse prognostic impact of tumour histological grade on survival differences between primary G2 and G3 WHO1973 stage T1 tumours which were graded as HG according to WHO2004 grading system. MATERIALS AND METHODS: Data from 481 patients with primary T1HG bladder cancer who were treated between 1986 and 2016 in 2university centres were retrospectively reviewed. Log-rank test and Cox regression analysis was performed to compare the groups. RESULTS: 95 (19,8%) tumours were classified as G2 and 386 (80,2%) were G3. Median follow-up was 68 months. The recurrence was observed in 228 (47,5%), and progression in 109 patients (22,7%). Radical cystectomy was performed in 114 pts (23,7%) and there were 64 (13,3%) cancer specific deaths. Recurrence-free rates at 5-years follow-up for G2, G3 and all patients were 68,7%, 51,2% and 56,3% and progression-free rates were 89,3%, 73,2% and 78,1% respectively. For total observation period patients with G3 tumours presented also worse recurrence-free, and progression-free survival levels than patients with G2 tumours. In multivariate analysis, after adjustment for clinical features, the risk of recurrence and progression for G3 tumours was 1,65 and 2,42 fold higher than for G2 tumours. CONCLUSIONS: It was shown that G3 T1 tumours are characterized by worse recurrence free and progression free survivals when compared to G2 cancers.


Asunto(s)
Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor/métodos , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Vejiga Urinaria/cirugía , Organización Mundial de la Salud
7.
Transplant Proc ; 50(6): 1597-1601, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30056867

RESUMEN

INTRODUCTION: After living kidney donation, a decrease of kidney function (described as estimated glomerular filtration rate [eGFR]) is observed in majority of donors. However, the loss is more significant in some patients without an explicable reason. The aim of this study was to identify quantitative parameters in computed tomography (CT) of the abdomen that would predict greater eGFR reduction after kidney removal. MATERIAL AND METHODS: One hundred and ten preoperative multiphase CT examinations of the abdomen of kidney donors were analyzed for the following renal parameters: cortex, parenchyma and pyramids volume, scarring thickness (low grade: <1 cm, high grade: >1 cm), cortical gaps, vascularisation, and cortex-to-aorta enhancement index (CAEI). The radiologic and biometric (eg, donor weight) parameters were correlated with eGFR (CKD-EPI formula) change between baseline and at discharge. RESULTS: Donor weight was correlated with a loss of eGFR (P < .001). Kidney volumetric parameters including renal cortex and parenchyma volume, as well as renal artery cross-section area were associated with donor weight (r = 0.50 P < .001 and r = 0.39 P < .001). CAEI was correlated with a loss of eGFR (P = .003) and was related to the donor's sex in favor of men. Forty-one (37%) donors had an additional renal artery, which did not influence kidney function. No influence of cortical gaps or scarring on eGFR was observed. CONCLUSIONS: CAEI may be a helpful tool in predicting greater short-term kidney function decrease after living kidney donation. Male sex is the strongest risk factor of greater eGFR loss after kidney donation.


Asunto(s)
Selección de Donante/métodos , Riñón/diagnóstico por imagen , Donadores Vivos , Cuidados Preoperatorios/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Tasa de Filtración Glomerular , Humanos , Riñón/fisiopatología , Trasplante de Riñón/métodos , Masculino , Persona de Mediana Edad , Nefrectomía/efectos adversos , Nefrectomía/métodos , Valor Predictivo de las Pruebas , Periodo Preoperatorio , Arteria Renal/diagnóstico por imagen , Arteria Renal/fisiopatología , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Recolección de Tejidos y Órganos/efectos adversos , Recolección de Tejidos y Órganos/métodos , Resultado del Tratamiento
8.
Mol Cell Biol ; 14(11): 7204-10, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7935435

RESUMEN

The mammalian transcriptional activator CREB binds as a dimer to a broad spectrum of inducible promoters. CREB activity is modulated by several signalling agents (protein kinase A [PKA], Ca2+, and transforming growth factor beta) and via functional interactions with cell-specific transcription factors. In addition, CREB can activate transcription constitutively and repress the activity of several other transcriptional activators. The mechanisms that allow CREB to act in such a malleable manner and the role that CREB dimerization might play in this are poorly understood. To probe the latter issue, we have created monomeric forms of CREB by fusing CREB to the DNA-binding domain of a protein (B-cell specific activator protein [BSAP]) that binds to DNA as a monomer. Remarkably, monomeric CREB acts as a potent, constitutive activator under conditions in which native CREB is inducible by PKA. Thus, CREB contains constitutive activation regions that are unable to function in native CREB. Two glutamine-rich domains that are important for native, PKA-inducible CREB activity are required for the constitutive activity of monomeric CREB. In contrast, two elements within the kinase-inducible domain of CREB are dispensable for constitutive activity. We discuss our results in relation to inducible and constitutive CREB activity and the potential modes of action of other activators that directly interact with CREB.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Factores de Transcripción , Secuencia de Bases , Sitios de Unión/genética , Línea Celular , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/química , ADN/genética , ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Genes Reporteros , Humanos , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Factor de Transcripción PAX5 , Regiones Promotoras Genéticas , Conformación Proteica , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Activación Transcripcional
9.
Br J Anaesth ; 99(6): 812-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17951609

RESUMEN

BACKGROUND: Previous studies demonstrated inactivation of vitamin B12 by nitrous oxide (N(2)O). The intraoperative exposure to N(2)O was shown to induce megaloblastic anaemia and myelopathy in subjects with subclinical vitamin B12 deficiency. In contrast, no data concerning the influence of occupational exposure to N(2)O on vitamin B12 metabolic status are available to date. In the present study, the vitamin B12 status in operating theatre personnel was assessed in relation to the extent of exposure. METHODS: Ninety-five operating theatre nurses with the history of exposure to N(2)O and 90 unexposed counterparts were examined. Vitamin B12 and folic acid were measured by immunoassay. Total homocysteine (tHcy), an indicator of impaired vitamin B12 metabolism, was determined by high performance liquid chromatography. N(2)O concentration was monitored by adsorption gas chromatography and mass spectrometry. RESULTS: No significant differences were found between both groups with respect to haematological parameters and folic acid. However, subjects exposed to N(2)O presented with lower vitamin B12 [372.8 (12.1) vs 436.8 (13.2) pmol litre(-1), P<0.001] and higher tHcy [11.2 (0.5) vs 8.9 (0.5) micromol litre(-1), P=0.006]. The changes in vitamin B12 status were aggravated in subjects exposed to N(2)O in concentrations substantially exceeding occupational exposure limit (180 mg m(-3)) [vitamin B12: 341.9 (17.7) vs 436.8 (13.2) pmol litre(-1), P=0.006; tHcy: 12.9 (0.7) vs 8.9 (0.5) micromol litre(-1), P=0.047]. CONCLUSIONS: Exposure to N(2)O in healthcare workers is associated with alterations of vitamin B12 metabolic status, the extent of which depends on the level of exposure.


Asunto(s)
Anestésicos por Inhalación/farmacología , Óxido Nitroso/farmacología , Exposición Profesional/análisis , Quirófanos , Vitamina B 12/sangre , Adulto , Anestésicos por Inhalación/análisis , Recolección de Muestras de Sangre/métodos , Relación Dosis-Respuesta a Droga , Monitoreo del Ambiente/métodos , Femenino , Ácido Fólico/sangre , Homocisteína/sangre , Humanos , Persona de Mediana Edad , Óxido Nitroso/análisis , Enfermería de Quirófano , Ventilación/métodos
10.
Exp Clin Endocrinol Diabetes ; 124(5): 263-75, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27219686

RESUMEN

Diabetes mellitus (DM), one of the most common life-threatening illnesses worldwide, is a group of metabolic diseases, characterized by sustained hyperglycemia. The global prevalence of diabetes mellitus among adults reached 387 millions in 2014 and is still rising. It is suggested there is a strong association between diabetes mellitus (especially type 2 diabetes mellitus) and carcinogenesis. The possible biological links between diabetes mellitus and cancer comprise hyperinsulinemia, hyperglycemia and fat-induced chronic inflammation. Although, the strongest association refers to pancreas and liver, there are many other organs involved in carcinogenesis in diabetic patients including breast, endometrium, bladder and kidney.Recent studies suggest that there is also association between cancer incidence and anti-diabetic medications. It was observed that some medications decrease the risk of carcinogenesis and some increase that risk. The majority of studies concern metformin, a drug of choice in type 2 diabetes mellitus, and its anti-neoplastic and tumor-suppressing activity. The positive effect of metformin was found in numerous researches investigating breast, pancreas, liver, colon, ovaries and prostate tumors.Because a variety of studies have suggested that diabetes mellitus and cancer are frequently coexisting diseases, recently published studies try to explain the influence of diabetes mellitus and anti-diabetic medications on carcinogenesis in different organs.We present the review of the latest studies investigating the association between both diabetes mellitus and anti-diabetic medications and cancer incidence and prognosis.Particularly we highlight the problem of concomitant head and neck cancers in diabetics, rarely analysed and often omitted in studies.


Asunto(s)
Comorbilidad , Diabetes Mellitus/epidemiología , Hipoglucemiantes/farmacología , Neoplasias/epidemiología , Diabetes Mellitus/tratamiento farmacológico , Humanos
11.
Mutat Res ; 581(1-2): 1-9, 2005 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-15725600

RESUMEN

It has been postulated that exposure to nitrous oxide and halogenated anaesthetics is associated with various adverse health effects such as neurological and reproductive abnormalities or impairment of hepatic functions. In spite of the quite well known genotoxic effects of exposure to nitrous oxide in vivo, the mechanisms of these effects are still not clear. The aim of this study was to assess the frequency of micronuclei and to identify the type of chromosomal damage (clastogenic or aneugenic) in peripheral blood lymphocytes of operating-room nurses exposed to nitrous oxide. The study group comprised 46 women working at departments where the concentration of nitrous oxide ranged from 14 to 2308 mg/m3. The control population was composed of 28 women employed in the same hospitals but in non-surgical departments. The clastogenic/aneugenic effect of nitrous oxide was evaluated in lymphocytes using the standard micronucleus (MN) assay in combination with the fluorescence in situ hybridization (FISH) technique with pancentromeric probes. The results show a significant increase of the MN frequency in lymphocytes of exposed nurses compared with the control group (4.36+/-2.23 versus 9.02+/-4.67). The multiple regression analysis revealed a statistically significant relationship (p=0.0009) between MN frequency and exposure status, indicating that the level of exposure was the main factor affecting chromosomal damage. As assessed by FISH analysis, the overall frequencies of centromere-positive MN in the control and exposed groups were 43 and 49%, respectively. The increase observed in the exposed group may suggest a slight, statistically insignificant pro-aneugenic effect of exposure to nitrous oxide.


Asunto(s)
Anestésicos por Inhalación/toxicidad , Cromosomas Humanos/efectos de los fármacos , Linfocitos/fisiología , Micronúcleos con Defecto Cromosómico , Óxido Nitroso/toxicidad , Enfermeras y Enfermeros , Adulto , Femenino , Humanos , Hibridación Fluorescente in Situ , Linfocitos/citología , Pruebas de Micronúcleos , Persona de Mediana Edad , Exposición Profesional , Estadística como Asunto
12.
FEBS Lett ; 361(2-3): 149-52, 1995 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-7698313

RESUMEN

In the present study chloroquine diphosphate, a DNA intercalating drug, was used to alter the internucleosomal DNA helical twist in chromatin of living mammalian cells. The intercalative binding of chloroquine effectively unwinds the DNA double helix and its binding is restricted to nucleosomal linker regions without noticeable disruption of nucleosomes. The results presented here imply that the alterations in the rotation angle between the adjacent nucleosomes in chromatin of eukaryotic cells in vivo significantly influences the way the chain of nucleosomes folds in higher-order chromatin structures, as evidenced by specific alterations in nuclease susceptibility of chromatin.


Asunto(s)
Cloroquina/análogos & derivados , Cromatina/ultraestructura , ADN de Neoplasias/química , Sustancias Intercalantes/farmacología , Conformación de Ácido Nucleico , Nucleosomas/ultraestructura , Cloroquina/farmacología , Cromatina/efectos de los fármacos , Cromatina/fisiología , ADN de Neoplasias/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Cinética , Leucemia Eritroblástica Aguda , Modelos Estructurales , Nucleosomas/fisiología , Células Tumorales Cultivadas
13.
FEBS Lett ; 358(1): 13-6, 1995 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-7821420

RESUMEN

The transcriptional control region of the Rouse sarcoma virus long terminal repeats (LTR) was shown to contain enhancer and promoter elements located within 200 base pairs upstream from the transcription initiation site [Cullen et al. (1985) Mol. Cell. Biol. 5, 438-447]. Deletion of these elements results in significant loss of LTR transcriptional activity. In the present paper it is shown that a short alternating purine-pyrimidine sequence can restore the constitutive activity of the Rouse sarcoma virus LTR in the absence of upstream elements when inserted in close proximity to the transcription initiator site. The possible molecular bases of this phenomena are discussed.


Asunto(s)
Virus del Sarcoma Aviar/genética , Regulación Viral de la Expresión Génica/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Transcripción Genética/genética , Línea Celular , Elementos de Facilitación Genéticos/genética , Células HeLa , Humanos , Modelos Genéticos , Conformación de Ácido Nucleico , Nucleosomas/metabolismo , Plásmidos/química , Plásmidos/genética , Regiones Promotoras Genéticas/genética , Proteínas Recombinantes de Fusión/biosíntesis , Eliminación de Secuencia
14.
FEBS Lett ; 452(3): 215-8, 1999 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-10386593

RESUMEN

DNA within chromatin has considerably more restricted flexibility in comparison with naked DNA. This raises the main question of how the functioning multi-enzyme complexes overcome the nucleosomal level of DNA packaging. We studied the DNA conformational flexibility of reconstituted chromatin in a cell-free system derived from Drosophila embryo extracts. Using this system, we have found evidence for a energy-independent chromatin remodelling process that efficiently destabilizes the nucleosome structure resulting in a high conformational flexibility of nucleosomal DNA. The described chromatin remodelling process may lay on the basis of defined molecular principles governing the molecular heterogeneity of chromatin structures in vivo.


Asunto(s)
Cromatina/ultraestructura , ADN/química , Embrión no Mamífero/ultraestructura , Conformación de Ácido Nucleico , Nucleosomas/ultraestructura , Animales , Sistema Libre de Células , Drosophila/embriología , Histonas/química , Nucleosomas/química
15.
Semin Arthritis Rheum ; 27(5): 293-300, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9572711

RESUMEN

OBJECTIVE: To assess the incidence of Reiter's syndrome aboard The Golden Venture, a ship carrying illegal immigrants from China to the United States. METHODS: After identification of an index case, we conducted telephone interviews with medical staff at immigrant detention centers in Pennsylvania, New York, and Virginia. When a potential case was identified at one facility, we performed a site inspection, reviewing the medical records of all detainees and performing histories and physicals on all those with joint and/or ocular complaints. RESULTS: We identified two patients, both HLA B27 positive, with Reiter's syndrome. The observed incidence (0.87%) approximated the predicted incidence but may have underestimated the actual incidence. We review the history of shipboard Reiter's syndrome, and discuss the pathogenic roles of HLA B27 and particular infectious agents. CONCLUSION: Continued transportation of illegal immigrants from China and other parts of the world is likely to result in occasional clusters of Reiter's syndrome. Physicians treating immigrant populations should remain aware of the possibility of reactive arthritis.


Asunto(s)
Artritis Reactiva/epidemiología , Brotes de Enfermedades , Emigración e Inmigración , Adulto , Artritis Reactiva/sangre , Artritis Reactiva/patología , Crimen , Antígeno HLA-B27/sangre , Humanos , Incidencia , Masculino , Navíos , Síndrome , Membrana Sinovial/patología , Estados Unidos/epidemiología
16.
J Biomol Struct Dyn ; 16(5): 1097-106, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10333179

RESUMEN

We evaluated the contribution of in vivo histone acetylation to the folding of chromatin into its higher-order structures. We have compared high-order folding patterns of hyperacetylated vs. unmodified chromatin in living green monkey kidney cells (CV1 line) using intercalator chloroquine diphospate to induce alterations in the twist of internucleosomal linker DNA. We have shown that histone hyperacetylation induced by antibiotic Trichostatin A significantly alters intercalator-mediated chromatin folding pattern.


Asunto(s)
Cromatina/química , Histonas/química , Acetilación , Animales , Células Cultivadas , Cloroquina/farmacología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Haplorrinos , Ácidos Hidroxámicos/farmacología , Sustancias Intercalantes/farmacología , Riñón/química , Modelos Biológicos , Péptido Hidrolasas/farmacología , Tripsina/farmacología
17.
J Biomol Struct Dyn ; 14(5): 641-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9130085

RESUMEN

We have used the intercalative agent ethidium bromide to examine the association between chromatin high-order folding and the twist of internucleosomal DNA regions. The analysis was carried out on intact nuclei isolated from human HeLa S3 cells. Our data shows that alterations in the nucleosomal linker twist significantly influence the way in which a chain of nucleosomes folds to form different higher-order structures. The assay used allowed us to identify the existence of two chromatin fractions differing in their extent of high-order folding. We have also found that active gene sequences are preferentially associated with the chromatin fraction corresponding to the more extended conformation. A model is proposed to account for the effect of variations in the nucleosome linker twist on the state of chromatin folding.


Asunto(s)
Núcleo Celular/ultraestructura , Cromatina/ultraestructura , ADN de Neoplasias/química , Conformación de Ácido Nucleico , Nucleosomas/ultraestructura , Núcleo Celular/efectos de los fármacos , Cromatina/efectos de los fármacos , ADN de Neoplasias/efectos de los fármacos , Etidio/farmacología , Células HeLa , Humanos , Sustancias Intercalantes/farmacología , Modelos Estructurales , Conformación de Ácido Nucleico/efectos de los fármacos , Nucleosomas/efectos de los fármacos
18.
J Biomol Struct Dyn ; 10(6): 1001-11, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8357538

RESUMEN

The conformational flexibility of DNA in transcriptionally active chromatin fractions has been estimated by circular dichroism spectroscopy analysis and was found to be restricted in the same fashion as in bulk chromatin. The observation is discussed in the context of different models of active chromatin organization.


Asunto(s)
ADN/química , ADN/metabolismo , Conformación de Ácido Nucleico , Nucleosomas/metabolismo , Animales , Fraccionamiento Celular , Núcleo Celular/metabolismo , Cromatina/metabolismo , Cromatina/ultraestructura , Dicroismo Circular , ADN/aislamiento & purificación , Electroforesis en Gel de Agar , Electroforesis en Gel de Poliacrilamida , Hígado/metabolismo , Modelos Estructurales , Nucleosomas/ultraestructura , Ratas , Termodinámica , Transcripción Genética
19.
J Biomol Struct Dyn ; 10(6): 1013-22, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8357539

RESUMEN

The "rigidity" of chromatin fiber solenoidal structure in different states of condensation was evaluated with the help of gel-electrophoresis. A new property of the unfolded nucleosomal fiber-the capacity to condense with temperature-was demonstrated. These results together with our previously obtained data (W.A. Krajewski et al., Mol. Gen. Genet. 230, pp. 442-448, 1991; W.A. Krajewski et al., Ibid. 231, pp. 17-22, 1991) testify that changes in DNA linking number of transcriptionally active minichromosomes arise in vivo from alteration of nucleosomal solenoid parameters (i.e. from supernucleosomal level of chromatin organization), rather than from core histone modifications only or from increased flexibility of DNA within nucleosomes.


Asunto(s)
Cromatina/ultraestructura , ADN/química , Conformación de Ácido Nucleico , Nucleosomas/ultraestructura , Animales , Fraccionamiento Celular , ADN/aislamiento & purificación , ADN/metabolismo , Electroforesis en Gel de Poliacrilamida , Histonas/aislamiento & purificación , Hígado/metabolismo , Modelos Estructurales , Ratas , Transcripción Genética
20.
Sci Total Environ ; 281(1-3): 37-45, 2001 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-11778958

RESUMEN

The aim of the study conducted on triticale and spring oilseed rape was to determine the role of liming, brown coal and compost medium in reducing the effect of cadmium contamination (at the rates of 0, 7.5, 15 and 22.5 mg Cd kg(-1) of soil) on yield and chemical composition of the crop. In the series of experiments without liming, a considerable decline in the yield of spring triticale grain, straw, root weight and green mass yield of rape was observed in response to the soil contamination with cadmium. Brown coal and especially compost medium added to soil neutralised the negative effect of cadmium on the grain yield and reduced a decrease in the yield of straw and roots of triticale. Soil liming proved to reduce the yield drop in oilseed rape caused by the contamination of soil with cadmium. The content of cadmium in roots and grain of spring triticale far exceeded that determined in triticale straw. The pollution of soil with cadmium caused a 26-fold increase in the content of this metal in grain, a 10-fold increase in roots of triticale and a twofold in oil-seed rape. Application of compost medium, brown coal and, to a smaller extent, liming reduced the level of cadmium in the parts of triticale brought to investigation. The soil contamination with cadmium caused certain modifications in the content of nitrogen, potassium, magnesium, calcium and sodium in spring triticale and in the content of N-total, potassium and magnesium in spring oilseed rape.


Asunto(s)
Brassica/química , Cadmio/farmacocinética , Compuestos de Calcio/química , Grano Comestible/química , Óxidos/química , Contaminantes del Suelo/farmacocinética , Cadmio/química , Compuestos de Calcio/farmacología , Carbón Mineral , Óxidos/farmacología , Distribución Tisular
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