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1.
Ann Oncol ; 29(4): 812-824, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29432557

RESUMEN

Background: Immune therapies have revolutionized cancer treatment over the last few years by allowing improvements in overall survival. However, the majority of patients is still primary or secondary resistant to such therapies, and enhancing sensitivity to immune therapies is therefore crucial to improve patient outcome. Several recent lines of evidence suggest that epigenetic modifiers have intrinsic immunomodulatory properties, which could be of therapeutic interest. Material and methods: We reviewed preclinical evidence and clinical studies which describe or exploit immunomodulatory properties of epigenetic agents. Experimental approaches, clinical applicability and corresponding ongoing clinical trials are described. Results: Several epigenetic modifiers, such as histone deacetylase inhibitors, DNA methyl transferase inhibitors, bromodomain inhibitors, lysine-specific histone demethylase 1 inhibitors and enhancer of zeste homolog 2 inhibitors, display intrinsic immunomodulatory properties. The latter can be achieved through the action of these drugs either on cancer cells (e.g. presentation and generation of neoantigens, induction of immunogenic cell death, modulation of cytokine secretion), on immune cells (e.g. linage, differentiation, activation status and antitumor capability), or on components of the microenvironment (e.g. regulatory T cells and macrophages). Several promising combinations, notably with immune checkpoint blockers or adoptive T-cell therapy, can be envisioned. Dedicated clinically relevant approaches for patient selection and trial design will be required to optimally develop such combinations. Conclusion: In an era where immune therapies are becoming a treatment backbone in many tumour types, epigenetic modifiers could play a crucial role in modulating tumours' immunogenicity and sensitivity to immune agents. Optimal trial design, including window of opportunity trials, will be key in the success of this approach, and clinical evaluation is ongoing.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Epigénesis Genética/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Adyuvantes Inmunológicos/farmacología , Muerte Celular/inmunología , Humanos , Neoplasias/inmunología , Neoplasias/patología
2.
Ann Oncol ; 28(2): 254-269, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28426098

RESUMEN

Background: Although the role of epigenetic abnormalities has been studied for several years in cancer genesis and development, epigenetic-targeting drugs have historically failed to demonstrate efficacy in solid malignancies. However, successful targeting of chromatin remodeling deficiencies, histone writers and histone reader alterations has been achieved very recently using biomarker-driven and mechanism-based approaches. Epigenetic targeting is now one of the most active areas in drug development and could represent novel therapeutic opportunity for up to 25% of all solid tumors. Material and methods: We reviewed preclinical and clinical studies that described epigenetic oncogenic addictions, synthetic lethal relationships or epigenetic antagonisms in chromatin regulators. Experimental approaches, their clinical relevance and applicability, as well as corresponding on-going studies are described. Results: The most successful approaches that have been clinically validated so far include the targeting of the BRD4-NUT fusion transcript in NUT-midline carcinoma by BET (Bromodomain Extra-Terminal) inhibitors, and the use of EZH2 (Enhancer of Zest Homolog 2) inhibitors in SMARCB1-deficient malignant rhabdoid tumors and SMARCA4-deficient ovarian small cell carcinomas. Clinical validation is still required for other synthetic lethal relationships or epigenetic antagonisms, including those described between EZH2 inhibitors and deficiencies in components of the Polycomb or SWI/SNF chromatin-remodeling complexes (including BAP1, ARID1A and PBRM1 subunits), as well as between the CREBBP and EP300 histone acetylases. Further, interplays between epigenetic modifiers and non-epigenetic cellular processes might be therapeutically exploited, and combinatorial strategies could be envisioned to overcome resistance or to sensitize cells to already approved drugs. Conclusion: Epigenetic-targeting drugs have historically failed proving efficacy in solid malignancies when used broadly, but novel mechanism-based approaches in molecularly selected patient populations have facilitated recent successes in proof-of-concept studies in solid tumors. Appropriate clinical trial design and molecular patient selection will be key for the success of epigenetic modifiers in solid tumours.


Asunto(s)
Epigénesis Genética/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Cromatina/genética , Ensamble y Desensamble de Cromatina , Regulación Neoplásica de la Expresión Génica , Humanos , Terapia Molecular Dirigida , Neoplasias/genética , Dependencia del Oncogén , Medicina de Precisión , Mutaciones Letales Sintéticas
3.
J Musculoskelet Neuronal Interact ; 16(3): 193-203, 2016 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-27609034

RESUMEN

OBJECTIVES: The aim of this study was to review the literature about the effect of whole body vibration exercise in the BMD in patients with postmenopausal osteoporosis without medications. METHODS: A systematic review was performed. RESULTS: The frequency of the mechanical vibration used in the protocols has varied from 12 to 90 Hz. The time used in the protocols varied from 2 up to 22 months. Techniques with X-rays were used in nine of the twelve publications analyzed, the Dual energy X-ray absorptiometry (DEXA) in eight studies and the High resolution peripheral quantitative computed tomography (HR-pQCT) in one publication. The concentration of some biomarkers was determined, as the sclerostin, the bone alkaline phosphatase, N-telopeptide X and 25-hydroxyvitamin D. Among the twelve articles analyzed, seven of them have shown an improvement of the BMD of some bone of postmenopausal women exposed to whole body vibration exercises not associated to medications; as well as modifications in biomarkers.


Asunto(s)
Densidad Ósea/fisiología , Terapia por Ejercicio/métodos , Osteoporosis Posmenopáusica/rehabilitación , Vibración/uso terapéutico , Anciano , Femenino , Humanos , Persona de Mediana Edad
4.
Cytopathology ; 24(1): 44-51, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22007754

RESUMEN

OBJECTIVES: Given the well-known poor reproducibility of cervical cytology diagnosis, especially for atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL), this study surveyed reproducibility in the assessment of individual cytomorphological features. METHODS: One hundred and fifty cells or groups of cells, with a variety of morphological appearances, including normal cells, high-grade squamous intraepithelial lesion (HSIL), LSIL, ASC-US and ASC cannot exclude HSIL (ASC-H), were precisely marked on 150 different liquid-based cytological preparations. They were analysed by 17 observers who assessed 17 cytological features including nuclear features (chromatin texture, nuclear outline, nuclear shape, etc.), cytoplasmic features (cell shape, cytoplasmic staining, cytoplasmic clearing, etc.) and group characteristics (nuclear polarity, cellular density, etc.). A total of 43,350 data scores were collected in a database using a web-based survey. Kendall's W and relative entropy indexes were utilized to compute concordance indexes of respectively ordinal and nominal variables. RESULTS: Nuclear features have significantly lower reproducibility (0.46) compared with other cytological features (0.59). The feature with least agreement is assessment of chromatin texture. A small but significant difference in concordance was found between two subsets of observers with different levels of experience. CONCLUSION: Most previous studies assessing reproducibility of cytological diagnoses show, at best, moderate reproducibility among observers. This study focused on agreement regarding the presence of constituent morphological features used to recognize dyskaryosis and various grades of squamous intraepithelial lesions. A map of reproducibility indexes is presented that highlights, for daily practice or teaching, the robustness of features used for cytological assessment, recognizing that diagnosis is always based on a combination of features.


Asunto(s)
Citodiagnóstico/métodos , Neoplasias de Células Escamosas/diagnóstico , Displasia del Cuello del Útero/diagnóstico , Recuento de Células , Núcleo Celular/patología , Forma del Núcleo Celular , Forma de la Célula , Cromatina/patología , Biología Computacional , Citoplasma/patología , Entropía , Femenino , Humanos , Clasificación del Tumor , Neoplasias de Células Escamosas/patología , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Coloración y Etiquetado , Displasia del Cuello del Útero/patología
5.
Am J Transplant ; 12(1): 202-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21967659

RESUMEN

Anti-cytomegalovirus (CMV) prophylaxis is recommended in D+R- kidney transplant recipients (KTR), but is associated with a theoretical increased risk of developing anti-CMV drug resistance. This hypothesis was retested in this study by comparing 32 D+R- KTR who received 3 months prophylaxis (valganciclovir) with 80 D+R- KTR who received preemptive treatment. The incidence of CMV infections was higher in the preemptive group than in the prophylactic group (60% vs. 34%, respectively; p = 0.02). Treatment failure (i.e. a positive DNAemia 8 weeks after the initiation of anti-CMV treatment) was more frequent in the preemptive group (31% vs. 3% in the prophylactic group; p = 0.001). Similarly, anti-CMV drug resistance (UL97 or UL54 mutations) was also more frequent in the preemptive group (16% vs. 3% in the prophylactic group; p = 0.05). Antiviral treatment failures were associated with anti-CMV drug resistance (p = 0.0001). Patients with a CMV load over 5.25 log(10) copies/mL displayed the highest risk of developing anti-CMV drug resistance (OR = 16.91, p = 0.0008). Finally, the 1-year estimated glomerular filtration rate was reduced in patients with anti-CMV drug resistance (p = 0.02). In summary, preemptive therapy in D+R- KTR with high CMV loads and antiviral treatment failure was associated with a high incidence of anti-CMV drug resistance.


Asunto(s)
Citomegalovirus/efectos de los fármacos , Farmacorresistencia Viral , Trasplante de Riñón , Humanos , Incidencia
6.
Hematol Oncol ; 29(1): 47-51, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20677173

RESUMEN

'Splenic red pulp lymphoma with numerous basophilic villous lymphocytes' (SRPL), recently described, is characterized by clinical, morphologic, immunologic, cytogenetic and molecular features distinct from SMZL/SLVL and HCL. In particular, the intensity of CD11c staining (expressed as fluorescence intensity -RFI-) in SRPL is significantly different from the RFI in SMZL/SLVL and HCL. Moreover the use of a scoring system based on the expression of CD11c, CD22, CD76, CD38 and CD27 appears to improve the differential diagnosis between SRPL and SMZL/SLVL and emphasizes that SRPL is an entity closed to but distinct from SMZL/SLVL.


Asunto(s)
Biomarcadores de Tumor/análisis , Antígeno CD11c/análisis , Linfoma de Células B/diagnóstico , Neoplasias del Bazo/diagnóstico , Diagnóstico Diferencial , Humanos , Linfoma de Células B/química , Linfoma de Células B/patología , Linfoma no Hodgkin/diagnóstico , Neoplasias del Bazo/química , Neoplasias del Bazo/patología
7.
Rev Med Suisse ; 7(298): 1255-6, 1258-9, 2011 Jun 08.
Artículo en Francés | MEDLINE | ID: mdl-21751722

RESUMEN

Therapeutic education was initially developed in the field of diabetology. In this chronic disease, it is the patient who is the major decision-maker. R. K. Bernstein is probably the first patient to have practised self glucose monitoring. He developed the basal-bolus technique for himself, which prompted the creation of functional insulin therapy courses by European physicians. This experiential approach has been adapted and simplified for patients in order to facilitate their management of uncertainty. The ASKAR method offers a frame of reference for the development of teaching-learning sequences. The acronym ASKAR refers to the five components of a person's experience: Action, Situation, Knowledge, Attitude and Resource. Working on these five components is a way for patients to improve their management of uncertainty.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Educación del Paciente como Asunto , Humanos
8.
Int J Prison Health ; 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34410050

RESUMEN

PURPOSE: This paper aims to describe the impact of the COVID-19 containment measures on the provision of drug treatment and harm reduction services in European prisons in15 countries during the early phase of the pandemic (March -June 2020). DESIGN/METHODOLOGY/APPROACH: The paper is based on a mixed method research approach that triangulates different data sources, including the results of an on-line survey, the outcome of a focus group and four national case studies. FINDINGS: The emergence of COVID-19 led to a disruption in prison drug markets and resulted in a number of challenges for the drug services provision inside prison. Challenges for health services included the need to maintain the provision of drug-related interventions inside prison, while introducing a range of COVID-19 containment measures. To reduce contacts between people, many countries introduced measures for early release, resulted in around a 10% reduction of the prison population in Europe. Concerns were expressed around reduction of drug-related interventions, including group activities, services by external agencies, interventions in preparation for release and continuity of care. PRACTICAL IMPLICATIONS: Innovations aimed at improving drug service provision included telemedicine, better partnership between security and health staff and an approach to drug treatment more individualised. Future developments must be closely monitored. ORIGINALITY/VALUE: The paper provides a unique and timely overview of the main issues, challenges and initial adaptations implemented for drug services in European prisons in response to the COVID-19 pandemic.

9.
Curr Med Chem ; 16(10): 1184-91, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19355878

RESUMEN

An intraperitoneal (IP) monotherapy in nu/nu mice with subcutaneous xenografts of a human prostate epithelial cancer cell line:DU145 was undertaken with an aldehyde dehydrogenase 3 inhibitor MATE, that is a potent apoptogen on (DU145) in culture but not on their human prostate epithelial normal counterparts [13] . Tumour growth was slowed down but treatment had to be done 5days/week. To try to potentiate the action of MATE in vivo, a bitherapy was undertaken based on the synergetic apoptotic effect that had been observed previously in culture on DU145 treated with a methional mimic METLICO and DIMATE, an inhibitor of ALDH1 and ALDH3 [19]. The bitherapy with METLICO/MATE administered IP was as effective as the monotherapy with MATE alone by IP, but at a 2-fold lower dose of MATE and at a dose of METLICO that had no growth-inhibitory effect as a monotherapy . Hence there was definite synergism with bitherapy. To try to increase the efficacy of bitherapy, it was administered by the intra-tumoral (IT) route using the recently developed 20-bars-pressurized microinjection system from CERMA [16, 17]. IT administration of the bitherapy was indeed more effective than that by IP as regards tumour volumes are concerned. Histopathological analysis of IT-treated tumours confirmed that there were many necrotized zones but intact cells were still present. Approaches for treating a wider zone of tumour tissue by IT-bitherapy are discussed.


Asunto(s)
Aldehído Deshidrogenasa/antagonistas & inhibidores , Aldehídos/química , Biomimética , Inhibidores Enzimáticos/uso terapéutico , Morfolinas/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Quinazolinas/uso terapéutico , Aldehídos/administración & dosificación , Aldehídos/uso terapéutico , Animales , Terapia Combinada , Sistemas de Liberación de Medicamentos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Femenino , Humanos , Inyecciones Intralesiones , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Desnudos , Estructura Molecular , Morfolinas/química , Neoplasias de la Próstata/patología , Quinazolinas/química , Carga Tumoral
10.
Respiration ; 75(1): 89-97, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17637510

RESUMEN

BACKGROUND: Decreased dipeptidylpeptidase IV (DPPIV) activity within the human nasal mucosa has previously been shown to contribute to the severity of chronic inflammatory rhinosinusitis. OBJECTIVE: To investigate and correlate the role of DPPIV activity with regard to bronchial inflammation. METHODS: DPPIV/CD26 activity/concentration was investigated in the bronchial tissue of human subjects suffering from chronic bronchial inflammation. In addition, the effect of a recombinant Aspergillus fumigatus DPPIV (fuDPPIV) was investigated on histamine-induced bronchoconstriction in anesthetized rabbits. RESULTS AND CONCLUSIONS: DPPIV/CD26 was present in submucosal seromucous glands, in leukocytes and to a very low degree in endothelial cells of human bronchi. DPPIV activity was correlated with tissue CD26 content measured by immunoassay. As previously reported for the nasal mucosa, DPPIV/CD26 activity was inversely correlated with the degree of airway inflammation. Systemic pretreatment with recombinant fuDPPIV markedly reduced the increase in histamine-induced airway resistance in rabbits. In conclusion, DPPIV activity modulates lower airway tone by degrading unknown peptidic substrates released by histamine in response to an allergen. Contrasting with our observations in the nose, this modulation is apparently not mediated via a neurokinin (NK1) receptor.


Asunto(s)
Hiperreactividad Bronquial/enzimología , Bronquitis Crónica/enzimología , Dipeptidil Peptidasa 4/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Animales , Biomarcadores/metabolismo , Hiperreactividad Bronquial/prevención & control , Bronquitis Crónica/patología , Broncoconstricción/efectos de los fármacos , Dipeptidil Peptidasa 4/farmacología , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Histamina/farmacología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mucosa Nasal/enzimología , Mucosa Nasal/fisiopatología , Probabilidad , Conejos , Valores de Referencia , Muestreo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Sustancia P/farmacología
11.
J Clin Invest ; 97(7): 1696-704, 1996 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8601635

RESUMEN

Pancreatic carboxyl ester lipase (CEL) hydrolyzes cholesteryl esters (CE), triglycerides (TG), and lysophospholipids, with CE and TG hydrolysis stimulated by cholate. Originally thought to be confined to the gastrointestinal system, CEL has been reported in the plasma of humans and other mammals, implying its potential in vivo to modify lipids associated with LDL, HDL (CE, TG), and oxidized LDL (lysophosphatidylcholine, lysoPC). We measured the concentration of CEL in human plasma as 1.2+/-0.5 ng/ml (in the range reported for lipoprotein lipase). Human LDL and HDL3 reconstituted with radiolabeled lipids were incubated with purified porcine CEL without or with cholate (10 or 100 microM, concentrations achievable in systemic or portal plasma, respectively). Using a saturating concentration of lipoprotein-associated CE (4 microM), with increasing cholate concentration there was an increase in the hydrolysis of LDL- and HDL3-CE; at 100 microM cholate, the present hydrolysis per hour was 32+/-2 and 1.6+/-0.1, respectively, indicating that CEL interaction varied with lipoprotein class. HDL3-TG hydrolysis was also observed, but was only approximately 5-10% of that for HDL3-CE at either 10 or 100 microM cholate. Oxidized LDL (OxLDL) is enriched with lysoPC, a proatherogenic compound. After a 4-h incubation with CEL, the lysoPC content of OxLDL was depleted 57%. Colocalization of CEL in the vicinity of OxLDL formation was supported by demonstrating in human aortic homogenate a cholate-stimulated cholesteryl ester hydrolytic activity inhibited by anti-human CEL IgG. We conclude that CEL has the capability to modify normal human LDL and HDL composition and structure and to reduce the atherogenicity of OxLDL by decreasing its lysoPC content.


Asunto(s)
Hidrolasas de Éster Carboxílico/metabolismo , Lipoproteínas/metabolismo , Páncreas/enzimología , Animales , Aorta Torácica/enzimología , Carboxilesterasa , Hidrolasas de Éster Carboxílico/sangre , Ésteres del Colesterol/metabolismo , Femenino , Humanos , Hidrólisis , Técnicas In Vitro , Lipoproteínas/química , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Lisofosfatidilcolinas/metabolismo , Masculino , Oxidación-Reducción , Porcinos , Triglicéridos/metabolismo
12.
Leukemia ; 20(2): 296-303, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16341050

RESUMEN

In most cases of lymphomas with blood dissemination, the careful cytological analysis of peripheral blood smears provides a rapid orientation to diagnosis, even if the final subtyping is achieved by histology and eventually other techniques. Here, we evaluated if the analysis of blood smears may suggest the blood dissemination of angioimmunoblastic T-cell lymphoma (AITL) and if CD10 expression on neoplastic T cells, as recently reported on AITL, may contribute to the diagnosis. In all, 11 lymph nodes and six peripheral blood samples from 12 patients with AITL were studied using four-colour flow cytometry associated to histological, cytological and molecular data. According to previous results, a fraction of T cells expressed CD10 in 10/11 lymph nodes. Interestingly, all blood smears showed atypical lymphoid cells and a fraction of T cells expressed CD10 with a mean percentage of 18.75% (range 5.00-47.00%), regardless of lymphocytosis level and of rate of CD10 T cells in corresponding lymph node. In contrast, in all control samples (100), none CD10-positive T cell was identified. This is to our knowledge the first description of circulating CD10 neoplastic T cells in AITL. Therefore, they ought to be explored in further studies when aggressive lymphoma, in particular with lymphopenia and circulating atypical cells, is suspected.


Asunto(s)
Linfoma de Células T/diagnóstico , Células Neoplásicas Circulantes/inmunología , Células Neoplásicas Circulantes/patología , Neprilisina/biosíntesis , Linfocitos T/inmunología , Linfocitos T/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Citometría de Flujo , Reordenamiento Génico , Genes Codificadores de la Cadena gamma de los Receptores de Linfocito T/genética , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Inmunohistoquímica , Inmunofenotipificación , Linfoma de Células T/sangre , Linfoma de Células T/patología , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
14.
Leukemia ; 19(10): 1818-23, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16094418

RESUMEN

The purpose of this study was to document the frequency and distribution of karyotypic changes present at diagnosis in 103 non-MALT marginal zone cell lymphoma (MZL) patients. This cytogenetic analysis of a large cohort extends previous observations and allows the identification of new cytogenetic features. Abnormalities identified in more than 15% of patients included +3/+3q (37%), 7q deletions (31%), +18/+18q (28%), 6q deletions (19%), +12/+12q (15%) and 8p deletions (15%). Trisomy 3/3q, 7q deletions, +18 and +12 were seen in different combinations in more than 30% of patients in comparison to 2% in lymphocytic lymphomas/chronic lymphocytic leukemias, 1% in mantle cell lymphomas and 7% in follicular lymphomas. The marked propensity of these abnormalities to be recurrently associated with the same tumoral clone of individual karyotypes allowed the delineation of a cytogenetic profile that may help to distinguish non-MALT MZL among other mature B-cell neoplasms. If +3/3q, +12/+12q, and 6q, 7q and 8p deletions were significantly associated with clinical prognostic factors previously reported to influence survival and time to progression, patients displaying these abnormalities did not experience a significantly shorter time to progression.


Asunto(s)
Linfoma de Células B de la Zona Marginal/genética , Linfoma de Células B/diagnóstico , Linfoma de Células B/genética , Adulto , Anciano , Anciano de 80 o más Años , Aberraciones Cromosómicas , Estudios de Cohortes , Análisis Citogenético , Progresión de la Enfermedad , Femenino , Humanos , Hibridación Fluorescente in Situ , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Linfoma de Células B/clasificación , Linfoma de Células B de la Zona Marginal/clasificación , Linfoma de Células B de la Zona Marginal/diagnóstico , Linfoma Folicular/diagnóstico , Linfoma Folicular/genética , Linfoma de Células del Manto/diagnóstico , Linfoma de Células del Manto/genética , Masculino , Persona de Mediana Edad , Factores de Tiempo
15.
Leukemia ; 13(3): 460-8, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10086737

RESUMEN

Unbalanced translocations involving chromosome arm 17p, where the TP53 tumor suppressor gene localizes, are rarely described in chronic lymphocytic leukemia and small lymphocytic lymphoma (CLL/SLL), but recent use of molecular cytogenetic techniques have indicated a significant incidence of TP53 deletions, suggesting the involvement of chromosome 17p in these disorders. By conventional karyotype, we have identified unbalanced translocations involving 17p in 14 out of 123 (11%) CLL/SLL patients with clonal abnormalities. Cases were characterized by resistance to chemotherapy and a poor clinical outcome. The karyotypes presented a high incidence of complex rearrangements and 17p translocations were characterized by various partners. In 10 cases a centric fusion was assessed by fluorescent in situ hybridization (FISH) experiments using specific centromeric probes. The incidence of dicentric translocations in these series is therefore significantly higher than usually described, arising in up to 71% (10 out of 14 cases). In all cases, translocations led to a monosomy 17p and to a TP53 monoallelic deletion. The adverse clinical outcome confirms that structural abnormalities involving chromosome 17p are associated with disease progression in patients with chronic lymphoproliferative disorders.


Asunto(s)
Cromosomas Humanos Par 17 , Leucemia Linfocítica Crónica de Células B/genética , Linfoma de Células B/genética , Translocación Genética , Antineoplásicos/uso terapéutico , Enfermedad Crónica , Cósmidos , Sondas de ADN , ADN Satélite/genética , Supervivencia sin Enfermedad , Genes p53 , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/patología , Resultado del Tratamiento
16.
J Leukoc Biol ; 38(2): 341-50, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3861749

RESUMEN

Free radicals are believed to be involved in leukocyte induced tissue injury. The present studies were performed to determine whether low density lipoprotein (LDL) might serve as a mediator of tissue injury after leukocyte induced free radical oxidation of LDL. Our results show that incubation of LDL with monocytes or polymorphonuclear leukocytes (PMN) leads to oxidation of the lipoprotein rendering it toxic to proliferating fibroblasts. Monocyte activation enhances these effects. Butylated hydroxytoluene (BHT), vitamin E (vit E) and glutathione (GSH) virtually prevent the oxidation of LDL and the formation of cytotoxic LDL, indicating that these alterations are mediated by leukocyte-derived free radicals. This is the first demonstration that short-lived free radicals emanating from phagocytic cells could mediate cell injury through the action of a stable cytotoxin formed by the oxidation of LDL. The fact that lipoproteins can transfer a cytotoxic effect from leukocytes to proliferating cells reveals a pathway for cell destruction which may have implications in atherosclerotic plaque progression, macrophage mediated toxicity to tumor cells and tissue injury by inflammatory processes.


Asunto(s)
Lipoproteínas LDL/toxicidad , Monocitos/fisiología , Neutrófilos/fisiología , Células Cultivadas , Fibroblastos/efectos de los fármacos , Radicales Libres , Humanos , Lipoproteínas LDL/metabolismo , Oxidación-Reducción
17.
J Leukoc Biol ; 61(5): 551-8, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9129203

RESUMEN

The microvascular endothelial cell (MVEC) is a major target of inflammatory cytokines overproduced in conditions such as sepsis and infectious diseases. We addressed the direct and indirect effects of tumor necrosis factor (TNF) on endothelial cells that can be relevant for the pathogenesis of septic shock, with particular attention to the acute respiratory distress syndrome (ARDS) and to cerebral malaria (CM). To identify functional and phenotypical changes occurring in MVEC during sepsis, we isolated these cells from the lungs of patients who died of ARDS. The constitutive expression of ICAM-1 and, to a lesser extent, VCAM-1, CD14, and TNFR2 were significantly increased on MVEC isolated from ARDS patients compared with control MVEC, whereas ELAM-1 and TNFR1 were not increased. We found that lung MVEC from ARDS patients present a procoagulant profile and a higher production capacity of interleukin-6 (IL-6) and IL-8 when compared with those from controls. As in pulmonary MVEC derived from ARDS patients, the only TNFR type found up-regulated in brain microvessels during CM was TNFR2. This increase in TNFR2 expression only occurred in CM-susceptible mice at the onset of the neurological syndrome. We therefore investigated the role of TNFR2 in the development of this brain pathology by comparing the incidence of CM in wild-type and TNF receptor knock-out mice. Unexpectedly, the genetic deficiency in TNFR2, but not in TNFR1, conferred protection against CM and its associated mortality. No ICAM-1 up-regulation was detected in the brain of Tnfr2 knockout mice, indicating a close correlation between protection against CM-associated brain damage, absence of TNFR2, and absence of ICAM-1 up-regulation in the brain. Our results in ARDS and CM indicate a specific up-regulation of TNFR2, but not of TNFR1, on lung and brain MVEC, respectively. This increased expression leads to a reduced sensitivity toward TNFR1-mediated phenomena, such as the sensitized TNF cytolytic activity on lung MVEC. In contrast, the sensitivity toward TNFR2-mediated effects, such as ICAM-1 induction by membrane-bound TNF, is increased on brain and lung MVEC expressing increased levels of TNFR2. Therefore, the ICAM-1-inducing effect, rather than the direct cytotoxicity of inflammatory cytokines, such as TNF, appears to be crucial in ARDS and CM-induced endothelial damage, and TNFR2 seems to play an important role in this activity in vivo.


Asunto(s)
Endotelio Vascular/ultraestructura , Malaria Cerebral/patología , Receptores del Factor de Necrosis Tumoral/fisiología , Síndrome de Dificultad Respiratoria del Recién Nacido/patología , Enfermedad Aguda , Animales , Endotelio Vascular/patología , Humanos , Recién Nacido , Ratones , Ratones Noqueados
18.
J Cereb Blood Flow Metab ; 3(2): 246-9, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6404914

RESUMEN

Although it is known that hypercarbia increases and benzodiazepines decrease cerebral blood flow (CBF), the effects of benzodiazepines on CBF responsiveness to CO2 are not well documented. The influence on CBF and CBF-CO2 sensitivity of placebo or midazolam, which is a new water-soluble benzodiazepine, was measured in eight healthy volunteers using the noninvasive 133Xe inhalation method for CBF determination. Under normocarbia, midazolam decreased CBF from 40.6 +/- 3.2 to 27.0 +/- 5.0 ml 100 g-1 min-1 (means +/- SD). At a later session under hypercarbia, CBF was 58.8 +/- 4.4 ml 100 g-1 min-1 after administration of placebo, and 49.1 +/- 10.2 ml 100 g-1 min-1 after midazolam. The mean of the slopes correlating PaCO2 and CBF was significantly steeper with midazolam (2.5 +/- 1.2 ml 100 g-1 min-1 mm Hg-1) than with placebo (1.5 +/- 0.4 ml 100 g-1 min-1 mm Hg-1). Our results suggest that midazolam may be a safe agent to use in patients with intracranial hypertension, since it decreases CBF and thus cerebral blood volume; however, it should be administered with caution in nonventilated patients with increased intracranial pressure, since its beneficial effects on cerebrovascular tone can be readily counteracted by the increase in arterial CO2 tension induced by this drug.


Asunto(s)
Benzodiazepinas/farmacología , Dióxido de Carbono/farmacología , Circulación Cerebrovascular/efectos de los fármacos , Sistema Vasomotor/efectos de los fármacos , Adulto , Arterias , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Midazolam , Presión Parcial
19.
Free Radic Biol Med ; 26(9-10): 1238-44, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10381195

RESUMEN

Carotenoids may protect low-density lipoprotein from oxidation, a process implicated in the development of atherosclerosis. Our previous studies showed that in vitro enrichment of low-density lipoprotein (LDL) with beta-carotene protected it from cell-mediated oxidation. However, in vitro enrichment with either lutein or lycopene actually enhanced oxidation of the LDL. In the present studies we have examined the impact of LDL carotenoid content on its oxidation by human aortic endothelial cells (EaHy-1) in culture, comparing the effects of in vivo supplementation with in vitro enrichments. The beta-carotene content in human LDL was increased three- to sixfold by daily supplementation with 15 mg beta-carotene for 4 weeks, and the lycopene content of LDL in other individuals was increased two- to threefold by ingestion of one glass (12 ounce) of tomato juice daily for 3 weeks. LDL isolated from these healthy, normolipidemic donors not taking supplemental carotenoid was incubated at 0.25 mg protein/ml with EaHy-1 cells in Ham's F-10 medium for up to 48 h. Following dietary beta-carotene supplementation, LDL oxidation (as assessed by formation of lipid hydroperoxides) was markedly inhibited, to an even greater extent than was observed for LDL enriched in vitro with beta-carotene (that resulted in an 11- to 12-fold increase in LDL beta-carotene). No effect on cell-mediated oxidation was observed, however, for LDL enriched in vivo with lycopene. Thus, beta-carotene appears to function as an antioxidant in protecting LDL from cell-mediated oxidation although lycopene does not. The fact that the three- to sixfold enrichments of LDL with beta-carotene achieved by dietary supplementation were more effective in inhibiting oxidation than the 11- to 12-fold enrichments achieved by an in vitro method suggests that dietary supplementation is a more appropriate procedure for studies involving the enrichment of lipoprotein with carotenoids.


Asunto(s)
Antioxidantes/administración & dosificación , Carotenoides/administración & dosificación , Dieta , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Lipoproteínas LDL/sangre , beta Caroteno/administración & dosificación , Adulto , Arteriosclerosis/prevención & control , Línea Celular , Radicales Libres/metabolismo , Humanos , Técnicas In Vitro , Peróxidos Lipídicos/sangre , Lipoproteínas LDL/química , Licopeno , Persona de Mediana Edad , Oxidación-Reducción
20.
Medicine (Baltimore) ; 77(6): 384-8, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9854601

RESUMEN

The combination of desmopressin (DDAVP) and behavioral therapy for treatment of nocturnal enuresis was compared with use of each of these modes alone. We randomly assigned 226 enuretic children being treated in primary care clinics of a major medical center in the largest health maintenance organization in Israel into 3 groups: Group A) DDAVP plus behavioral therapy (double-blind); Group B) behavioral therapy plus placebo (double-blind); and Group C) DDAVP alone (open group). DDAVP (20 micrograms/naris) and placebo were administered by intranasal spray. Both pharmacologic and behavioral therapy were initiated after a 2-week observation period and continued for 8 weeks. All patients were followed for 2 months after completion of treatment. A significant reduction in the number of wet nights/week was registered for all 3 groups: 49% in Group A, 45% in Group B, and 19% in Group C. After controlling for confounding factors, no significant difference in effect was noted among the 3 types of treatment during the trial period. However, on follow-up the results for the DDAVP patients were significantly less stable compared with the other 2 groups (p = 0.015). Minor side effects were registered, but none of the participants withdrew from the trial. To our knowledge, this is the largest randomized trial of nocturnal enuresis conducted to date. Our findings suggest that simply discussing the problem with the patient and family leads to improvement, and that behavioral therapy is also beneficial. DDAVP can help, but the relapse rate on discontinuation is high.


Asunto(s)
Terapia Conductista , Desamino Arginina Vasopresina/uso terapéutico , Enuresis/terapia , Fármacos Renales/uso terapéutico , Adolescente , Niño , Terapia Combinada , Método Doble Ciego , Femenino , Humanos , Masculino , Recurrencia , Resultado del Tratamiento
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