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1.
Genetica ; 150(5): 235-246, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35543891

RESUMEN

Known as "electric-light bugs", belostomatids potentially act as agents of biological control. The Belostoma genus has holokinetic chromosomes, interspecific variation in diploid number, sex chromosome system and DNA content. Thus, the chromosomal complement, the accumulation of constitutive heterochromatin and the distribution of rDNA clusters by fluorescence in situ hybridization (FISH) in Belostoma angustum (BAN), Belostoma sanctulum (BSA), and Belostoma nessimiani (BNE) were evaluated. In addition, a comparative analysis of the DNA content of these species and B. estevezae (BES) was performed. BES has the highest Belostoma DNA content, while BSA has the lowest. BAN showed 2n = 29 + X1X2Y, while BSA and BNE had 2n = 14 + XY. BSA showed 18S rDNA markings on sex chromosomes, while BNE and BAN did on autosomes. The difference between BSA and BNE occurs because of the possible movement of the rDNA cluster in BNE. We suggest the occurrence of fusion in the autosomes of BSA and BNE, and fragmentation in the sex chromosomes in BAN. Also, the genome size of 1-2 pg represents a haploid DNA content of a common ancestor, from which the genomes of BES and BAN had evolved by gene duplication and heterochromatinization events.


Asunto(s)
Heterópteros , Ácidos Alcanesulfónicos , Animales , ADN Ribosómico/genética , Tamaño del Genoma , Heterocromatina/genética , Heterópteros/genética , Hibridación Fluorescente in Situ , Cromosomas Sexuales
2.
Pestic Biochem Physiol ; 146: 63-70, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29626993

RESUMEN

BACKGROUND: Plants have developed a vast range of mechanisms to compete with phytophagous insects, including entomotoxic proteins such as ureases. The legume Canavalia ensiformis produces several urease isoforms, of which the more abundant is called Jack Bean Urease (JBU). Previews work has demonstrated the potential insecticidal effects of JBU, by mechanisms so far not entirely elucidated. In this work, we investigated the mechanisms involved in the JBU-induced activity upon neurotransmitter release on insect neuromuscular junctions. METHODS: Electrophysiological recordings of nerve and muscle action potentials, and calcium imaging bioassays were employed. RESULTS AND CONCLUSION: JBU (0.28 mg/animal/day) in Locusta migratoria 2nd instar through feeding and injection did not induce lethality, although it did result in a reduction of 20% in the weight gain at the end of 168 h (n = 9, p ≤ 0.05). JBU (0.014 and 0.14 mg) injected direct into the locust hind leg induced a dose and time-dependent decrease in the amplitude of muscle action potentials, with a maximum decrease of 70% in the amplitude at the highest dose (n = 5, p ≤ 0.05). At the same doses JBU did not alter the amplitude of action potentials evoked from motor neurons. Using Drosophila 3rd instar larvae neuromuscular preparations, JBU (10-7 M) increased the occurrence of miniature Excitatory Junctional Potentials (mEJPs) in the presence of 1 mM CaCl2 (n = 5, p ≤ 0.05). In low calcium (0.4 mM) assays, JBU (10-7 M) was not able to modulate the occurrence of the events. In Ca2+-free conditions, with EGTA or CoCl2, JBU induced a significant decrease in the occurrence of mEPJs (n = 5, p ≤ 0.05). Injected into the 3rd abdominal ganglion of Nauphoeta cinerea cockroaches, JBU (1 µM) induced a significant increase in Ca2+ influx (n = 7, p ≤ 0.01), similar to that seen for high KCl (35 mM) condition. Taken together the results confirm a direct action of JBU upon insect neuromuscular junctions and possibly central synapses, probably by disrupting the calcium machinery in the pre-synaptic region of the neurons.


Asunto(s)
Acetilcolinesterasa/genética , Lepidópteros/genética , Mutación , Animales , España
3.
J Transl Med ; 14(1): 288, 2016 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-27729044

RESUMEN

Gene therapy protocols require robust and long-term gene expression. For two decades, retrovirus family vectors have offered several attractive properties as stable gene-delivery vehicles. These vectors represent a technology with widespread use in basic biology and translational studies that require persistent gene expression for treatment of several monogenic diseases. Immunogenicity and insertional mutagenesis represent the main obstacles to a wider clinical use of these vectors. Efficient and safe non-viral vectors are emerging as a promising alternative and facilitate clinical gene therapy studies. Here, we present an updated review for beginners and expert readers on retro and lentiviruses and the latest generation of transposon vectors (sleeping beauty and piggyBac) used in stable gene transfer and gene therapy clinical trials. We discuss the potential advantages and disadvantages of these systems such as cellular responses (immunogenicity or genome modification of the target cell) following exogenous DNA integration. Additionally, we discuss potential implications of these genome modification tools in gene therapy and other basic and applied science contexts.


Asunto(s)
Elementos Transponibles de ADN/genética , Terapia Genética/métodos , Vectores Genéticos/metabolismo , Retroviridae/genética , Animales , Ensayos Clínicos como Asunto , Humanos , Transposasas/metabolismo
4.
Sci Rep ; 14(1): 10079, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698037

RESUMEN

Over the last quarter century, increasing honey bee colony losses motivated standardized large-scale surveys of managed honey bees (Apis mellifera), particularly in Europe and the United States. Here we present the first large-scale standardized survey of colony losses of managed honey bees and stingless bees across Latin America. Overall, 1736 beekeepers and 165 meliponiculturists participated in the 2-year survey (2016-2017 and 2017-2018). On average, 30.4% of honey bee colonies and 39.6% of stingless bee colonies were lost per year across the region. Summer losses were higher than winter losses in stingless bees (30.9% and 22.2%, respectively) but not in honey bees (18.8% and 20.6%, respectively). Colony loss increased with operation size during the summer in both honey bees and stingless bees and decreased with operation size during the winter in stingless bees. Furthermore, losses differed significantly between countries and across years for both beekeepers and meliponiculturists. Overall, winter losses of honey bee colonies in Latin America (20.6%) position this region between Europe (12.5%) and the United States (40.4%). These results highlight the magnitude of bee colony losses occurring in the region and suggest difficulties in maintaining overall colony health and economic survival for beekeepers and meliponiculturists.


Asunto(s)
Apicultura , Estaciones del Año , Animales , Abejas/fisiología , América Latina
5.
Plasmid ; 68(3): 179-85, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22728068

RESUMEN

Gene transfer based on lentiviral vectors allow the integration of exogenous genes into the genome of a target cell, turning these vectors into one of the most used methods for stable transgene expression in mammalian cells, in vitro and in vivo. Currently, there are no lentivectors that allow the cloning of different genes to be regulated by different promoters. Also, there are none that permit the analysis of the expression through an IRES (internal ribosome entry site)-- reporter gene system. In this work, we have generated a series of lentivectors containing: (1) a malleable structure to allow the cloning of different target genes in a multicloning site (mcs); (2) unique site to exchange promoters, and (3) IRES followed by one of two reporter genes: eGFP or DsRed. The series of the produced vectors were named pLR (for lentivirus and RSV promoter) and were fairly efficient with a strong fluorescence of the reporter genes in direct transfection and viral transduction experiments. This being said, the pLR series have been found to be powerful biotechnological tools for stable gene transfer and expression.


Asunto(s)
Vectores Genéticos , Lentivirus/genética , Transducción Genética , Transgenes , Proteínas Fluorescentes Verdes/genética , Células HEK293 , Humanos , Regiones Promotoras Genéticas
6.
Invest New Drugs ; 27(6): 517-25, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19050827

RESUMEN

Malignant gliomas are the most common and devastating primary tumors of the central nervous system. Currently no efficient treatment is available. This study evaluated the effect and underlying mechanisms of boldine, an aporphine alkaloid of Peumus boldus, on glioma proliferation and cell death. Boldine decreased the cell number of U138-MG, U87-MG and C6 glioma lines at concentrations of 80, 250 and 500 muM. We observed that cell death caused by boldine was cell-type specific and dose-dependent. Exposure to boldine for 24 h did not activate key mediators of apoptosis. However, it induced alterations in the cell cycle suggesting a G(2)/M arrest in U138-MG cells. Boldine had no toxic effect on non-tumor cells when used at the same concentrations as those used on tumor cells. Based on these results, we speculate that boldine may be a promising compound for evaluation as an anti-cancer agent.


Asunto(s)
Antineoplásicos/uso terapéutico , Aporfinas/farmacología , Aporfinas/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Glioma/tratamiento farmacológico , Glioma/patología , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Aporfinas/química , Encéfalo/efectos de los fármacos , Encéfalo/patología , Neoplasias Encefálicas/enzimología , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Daño del ADN , Ensayos de Selección de Medicamentos Antitumorales , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Glioma/enzimología , Humanos , Técnicas In Vitro , Masculino , Mitosis/efectos de los fármacos , Ratas , Ratas Wistar
8.
Mol Cell Biochem ; 319(1-2): 61-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18636315

RESUMEN

Malignant gliomas are the most common and devastating primary tumors in the brain and, despite treatment, patients with these tumors have a poor prognosis. The participation of ecto-5'-NT/CD73 per se as a proliferative factor, being involved in the control of cell growth, differentiation, invasion, migration and metastasis processes has been previously proposed. In the present study, we evaluated the activity and functions of ecto-5'-NT/CD73 during the proliferation process of rat C6 and human U138MG glioma cell lines. Increasing confluences and culture times led to an increase in ecto-5'-NT/CD73 activity in both C6 and U138MG glioma cells. RT-PCR analysis and flow cytometry analysis showed a significant increase in ecto-5'-NT/CD73 mRNA and protein levels, respectively, comparing confluent with sub-confluent cultures in human U138MG glioma cells. Ecto-5'-nucleotidase/CD73 may regulate the extracellular adenosine 5'-monophosphate (AMP) and adenosine levels. Treatment with 1 microM APCP, a competitive ecto-5'-NT/CD73 inhibitor, caused a significant reduction of 30% in glioma cell proliferation. In addition, 100 microM adenosine increases cell proliferation by 36%, and the treatment with adenosine plus NBTI and dipyridamole, produced an additional and significant increase of on cell proliferation. The inhibitory effect on cell proliferation caused by APCP was reverted by co-treatment with NBTI and dipyridamole. AMP (1 mM and 3 mM) decreased U138MG glioma cell proliferation by 29% and 42%, respectively. Taken together, these results suggest the participation of ecto-5'-NT/CD73 in cell proliferation and that this process is dependent upon the enzyme's production of adenosine, a proliferative factor, and removal of AMP, a toxic molecule for gliomas.


Asunto(s)
5'-Nucleotidasa/biosíntesis , Neoplasias Encefálicas/enzimología , Proliferación Celular , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioma/enzimología , 5'-Nucleotidasa/antagonistas & inhibidores , Adenosina/metabolismo , Adenosina/farmacología , Adenosina Monofosfato/metabolismo , Marcadores de Afinidad/farmacología , Animales , Neoplasias Encefálicas/patología , Diferenciación Celular , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Glioma/patología , Humanos , Invasividad Neoplásica , Metástasis de la Neoplasia , Ratas , Tioinosina/análogos & derivados , Tioinosina/farmacología
9.
Toxicol In Vitro ; 22(5): 1205-12, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18474417

RESUMEN

Even though RA is involved in differentiation and apoptosis of normal and cancer cells, being sometimes used as adjuvant in chemotherapy, its mechanisms of action involve multiple overlapping pathways that still remain unclear. Recent studies point out that RA exerts rapid and non-genomic effects, which are independent of RAR/RXR-mediated gene transcription. In this work, we reported that RA treatment for 24 h decreases cell viability, induces apoptosis dependent on caspase-3 activation, and activates the transcription factor AP-1 in cultured Sertoli cells. Moreover, RA induced a rapid and non-classical stimulation of ERK1/2. ERK1/2 activation was mediated by MEK1/2, and the protein synthesis inhibitor cycloheximide did not alter the pattern of RA-induced ERK1/2 phosphorylation. Pharmacological inhibition of MEK1/2-ERK1/2 pathway with UO126 blocked caspase-3 activation, decreased AP-1 binding to DNA and inhibited apoptosis. Overall, our data suggest that a rapid and non-genomic effect of RA upon MEK1/2-ERK1/2 pathway leads to caspase-3 activation and caspase-3-dependent apoptosis in cultured Sertoli cells. The non-canonical RA signaling presented in this work evokes new perspectives of RA action, which may play an important role in mediating early biological effects of RA modulating cell death in normal and tumor cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Células de Sertoli/efectos de los fármacos , Tretinoina/toxicidad , Vitaminas/toxicidad , Animales , Butadienos/farmacología , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cicloheximida/farmacología , ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática , MAP Quinasa Quinasa 1/metabolismo , Masculino , Nitrilos/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Ratas , Células de Sertoli/enzimología , Células de Sertoli/patología , Factor de Transcripción AP-1/biosíntesis , Factor de Transcripción AP-1/fisiología , Transcripción Genética/efectos de los fármacos
10.
Sao Paulo Med J ; 126(2): 75-81, 2008 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-18553028

RESUMEN

CONTEXT AND OBJECTIVES: There are few studies concerning bone marrow mononuclear cell (BMMC) transplantation in cases of nonischemic dilated cardiomyopathy. This study describes a novel technique of BMMC transplantation and the results up to one year after the procedure. DESIGN AND SETTING: This was a case series to evaluate the safety and viability of the procedure, at Instituto de Cardiologia do Rio Grande do Sul. METHODS: Nine patients with symptomatic dilated cardiomyopathy, functional class III/IV and left ventricular ejection fraction (LVEF) < 35% received BMMC (9.6 +/- 2.6 x 107 cells) at 20 sites in the ventricular wall, by means of thoracotomy of length 5 cm in the fifth left intercostal space. Echocardiograms and nuclear magnetic resonance (NMR) were performed. RESULTS: There were no major complications. The functional class results for the first six patients (preoperatively and at two, four, eight and twelve-month follow-ups, respectively) were: [IV-2, III-4] to [I-5, II-1] to [I-3, II-3] to [I-2, II-3] and [I-2, II-3]. Echocardiograms showed LVEF: 25.9 +/- 8.2; 32.9 +/- 10.4; 29.4 +/- 7.2; 25.1 +/- 7.9; 25.4 +/- 6.8% (p = 0.023); and % left ventricular (LV) fiber shortening: 12.6 +/- 4.4; 16.4 +/- 5.4; 14.3 +/- 3.7; 12.1 +/- 4.0; 12.2 +/- 3.4% (p = 0.021). LV performance variation seen on NMR was non-significant. CONCLUSION: Intramyocardial transplantation of BMMC in dilated cardiomyopathy cases is feasible and safe. There were early improvements in symptoms and LV performance. Medium-term evaluation revealed regression of LV function, although maintaining improved functional class.


Asunto(s)
Trasplante de Médula Ósea/métodos , Cardiomiopatía Dilatada/cirugía , Trasplante de Células Madre/métodos , Toracotomía/métodos , Estudios de Factibilidad , Femenino , Humanos , Inmunofenotipificación , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Volumen Sistólico/fisiología , Factores de Tiempo , Trasplante Autólogo , Resultado del Tratamiento , Función Ventricular Izquierda/fisiología
11.
Eur J Pharmacol ; 569(1-2): 8-15, 2007 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-17568578

RESUMEN

Gliomas are the most common and devastating primary tumors of the central nervous system. Ecto-NTPDases and ecto-5'-nucleotidase/CD73 can control extracellular ATP/adenosine levels, which have been described as proliferation factors. Here, we investigate the influence of indomethacin on the enzyme cascade that catalyses the interconversion of purine nucleotides in U138-MG and C6 glioma cell lines. Exposure of glioma cells to 100 microM indomethacin for 48 h caused increases of 52% (P < 0.05) and 62% (P < 0.05) in the AMP hydrolysis rate in C6 and U138-MG cell lines, respectively. Indomethacin treatments also increased ATP hydrolysis. Significant increase in ecto-5'-nucleotidase/CD73 mRNA and protein levels were observed after treatment with indomethacin. Pretreatment of glioma cells with a specific antagonist of the adenosine A(3) receptor, MRS1220 (1 microM; 9-Chloro-2-(2-furanyl)-5-((phenylacetyl)amino)-[1,2,4]triazolo[1,5-c]quinazoline), significantly reduced the inhibition of cell proliferation induced by indomethacin. In addition, a significant increase in mRNA levels of the adenosine A(3) receptor was observed after treatment with indomethacin. In conclusion, our data indicate that adenosine A(3) receptors and the enzyme, ecto-5'-nucleotidase/CD73, are involved in the anti-proliferative effect of indomethacin in glioma cells.


Asunto(s)
5'-Nucleotidasa/genética , Indometacina/farmacología , 5'-Nucleotidasa/metabolismo , Actinas/metabolismo , Adenosina Difosfato/análogos & derivados , Adenosina Difosfato/metabolismo , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Antiinflamatorios no Esteroideos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glioma/enzimología , Glioma/genética , Glioma/patología , Humanos , Agonistas del Receptor Purinérgico P1 , Antagonistas de Receptores Purinérgicos P1 , Quinazolinas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Teofilina/análogos & derivados , Teofilina/farmacología , Factores de Tiempo , Triazoles/farmacología , Xantinas/farmacología
12.
Cancer Biol Ther ; 18(8): 560-570, 2017 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-28692326

RESUMEN

BACKGROUND: Eukaryote initiation factor 2 subunit ß (eIF2ß) plays a crucial role in regulation protein synthesis, which mediates the interaction of eIF2 with mRNA. eIF2ß contains evolutionarily conserved polylysine stretches in amino-terminal region and a zinc finger motif in the carboxy-terminus. METHODS: The gene eIF2ß was cloned under tetracycline transcription control and the polylysine stretches were deleted by site-directed mutagenesis (eIF2ßΔ3K). The plasmid was transfected into HEK 293 TetR cells. These cells were analyzed for their proliferative and translation capacities as well as cell death rate. Experiments were performed using gene reporter assays, western blotting, flow cytometry, cell sorting, cell proliferation assays and confocal immunofluorescence. RESULTS: eIF2ßΔ3K affected negatively the protein synthesis, cell proliferation and cell survival causing G2 cell cycle arrest and increased cell death, acting in a negative dominant manner against the native protein. Polylysine stretches are also essential for eIF2ß translocated from the cytoplasm to the nucleus, accumulating in the nucleolus and eIF2ßΔ3K did not make this translocation. DISCUSSION: eIF2ß is involved in the protein synthesis process and should act in nuclear processes as well. eIF2ßΔ3K reduces cell proliferation and causes cell death. Since translation control is essential for normal cell function and survival, the development of drugs or molecules that inhibit translation has become of great interest in the scenario of proliferative disorders. In conclusion, our results suggest the dominant negative eIF2ßΔ3K as a therapeutic strategy for the treatment of proliferative disorders and that eIF2ß polylysine stretch domains are promising targets for this.


Asunto(s)
Proliferación Celular/genética , Factor 2B Eucariótico de Iniciación/genética , Puntos de Control de la Fase G2 del Ciclo Celular/genética , Polilisina/genética , Biosíntesis de Proteínas/genética , Eliminación de Secuencia/genética , Apoptosis/genética , Sitios de Unión , Núcleo Celular/metabolismo , Supervivencia Celular/genética , Citoplasma/metabolismo , Factor 2B Eucariótico de Iniciación/metabolismo , Células HEK293 , Humanos , Terapia Molecular Dirigida/métodos , Mutagénesis Sitio-Dirigida , Neoplasias/terapia , Unión Proteica , Transporte de Proteínas , ARN Mensajero/metabolismo
13.
Eur J Pharmacol ; 532(3): 214-22, 2006 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-16487511

RESUMEN

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used drugs for the treatment of inflammatory disease and have a chemopreventive effect in a variety of tumors. Several studies have demonstrated unequivocally that certain NSAIDs cause antiproliferative effects independent of cyclooxygenase (COX) activity. In this study, we investigated the effect of chemically unrelated NSAIDs in the proliferation of glioma cell lines and the possible mechanisms involved in indomethacin-mediated inhibition of proliferation in glioma cells lines. The glioma cell lines were treated with NSAIDs and proliferation was measured by cell counting. Indomethacin, acetaminophen, sulindac sulfide and NS-398 (N-[2-cyclohexyloxy)-4-nitrophenyl]methane-sulfonamide) induced a time- and concentration-dependent inhibition of C6 rat glioma cell proliferation. The inhibition of COX by chemically unrelated NSAIDs leads to inhibition of rat and human glioma cell proliferation. The tetrazolium reduction assay (MTT) indicated a reduction in cell viability induced by indomethacin. None of the NSAIDs tested induced caspase-3/7 activation, assayed with a fluorigenic substrate. The indomethacin-induced inhibition of C6 cells proliferation was abrogated by the use of the c-Src inhibitor, PP2 and the MEK inhibitor, PD 098059, suggesting COX-independent mechanisms. Indomethacin decreased the percentage of cells in the S phase, with relative increases in the G0/G1 and/or the G2/M phase. NSAIDs may be clinically important for pharmacological intervention in gliomas.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Proliferación Celular/efectos de los fármacos , Inhibidores de la Ciclooxigenasa/farmacología , Indometacina/farmacología , Nitrobencenos/farmacología , Sulfonamidas/farmacología , Acetaminofén/farmacología , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Flavonoides/farmacología , Glioma , Humanos , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Ratas , Factores de Tiempo , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/metabolismo
14.
Cancer Lett ; 288(2): 192-203, 2010 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-19646807

RESUMEN

A growing body of evidence suggests the inhibition of NFkappaB as a strategy to induce cell death in tumor cells. In this work, we evaluated the effects of the pharmacological NFkappaB inhibitors BAY117082 and MG132 on leukemia cells apoptosis. BAY117082 and MG132 presented potent apoptotic effects compared to inhibitors of MAPKs, EGFR, PI3K/Akt, PKC and PKA signaling pathways. Non-tumor peripheral blood cells were insensitive to BAY117082 and MG132 apoptotic effects. BAY117082 and MG132-induced apoptosis was dependent on their ability to increase ROS as a prelude to mitochondria membrane potential (MMP) depolarization, permeability transition pore opening and cytochrome c release. Antioxidants blocked MG132 and BAY117082 effects on ROS, MMP and cell death. Although apoptotic markers as phosphatidylserine externalization, chromatin condensation and sub-G1 were detected in BAY117082-treated cells, caspases activation did not occur and apoptosis was insensitive to caspase inhibitors, suggesting a caspase-independent mechanism. In contrast, MG132 induced classical apoptosis through ROS-mitochondria and subsequent caspase-9/caspase-3 activation. At sub-apoptotic concentrations, BAY117082 and MG132 arrested cells in G2/M phase of the cell cycle and blocked doxorubicin-induced NFkappaB, which sensitized doxorubicin-resistant cells. Data suggest that the NFkappaB inhibitors MG132 and BAY117082 are potential anti-leukemia agents.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Leucemia/patología , Leupeptinas/farmacología , Mitocondrias/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Nitrilos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Sulfonas/farmacología , Antibióticos Antineoplásicos/farmacología , Caspasas/metabolismo , Citocromos c/metabolismo , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Activación Enzimática , Humanos , Células Jurkat , Células K562 , Leucemia/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Proteínas de Transporte de Membrana Mitocondrial/efectos de los fármacos , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Poro de Transición de la Permeabilidad Mitocondrial , FN-kappa B/metabolismo , Factores de Tiempo , Células U937
15.
Tissue Antigens ; 71(5): 440-6, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18331529

RESUMEN

We tested the possible association of the 14-bp polymorphism of the HLA-G gene in the course of two inflammatory diseases, rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA). Patients and controls were genotyped for the 14-bp polymorphism by polymerase chain reaction with specific primers for the exon 8 of the human leukocyte antigen (HLA)-G gene and the amplified fragment was visualized in a 6% polyacrylamide gel. A total of 106 JIA patients, 265 RA patients, 356 healthy adults and 85 healthy children were genotyped for the 14-bp polymorphism. Female JIA patients presented a higher frequency of the -14 bp allele when compared with female healthy children (0.743 and 0.500, corrected P=0.003), which reflected in the JIA group as a whole. This increased frequency of the -14-bp allele was observed in all JIA subtypes. In RA patients, no differences in allelic and genotypic frequencies were observed between patients and controls. No correlations were observed among genotype and disease severity or clinical manifestations. Our data suggest that the HLA-G -14 bp allele is probably a risk factor for JIA, mainly in females. Considering the differences observed in relation to gender, we suggest that hormonal differences can interfere with the development of JIA. Considering the RA patients, our data agree with results from the literature and highlight the differences in the etiology of RA and JIA.


Asunto(s)
Artritis Juvenil/genética , Artritis Reumatoide/genética , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase I/genética , Mutagénesis Insercional , Eliminación de Secuencia , Adolescente , Anciano , Alelos , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Antígenos HLA-G , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético
16.
Cytotechnology ; 51(3): 141-8, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19002884

RESUMEN

The improvement of gene therapy protocols is intimately related to the establishment of efficient gene transfer methods. Electroporation has been increasingly employed in in vitro and in vivo protocols, and much attention has been given to increasing its transfection potential. The method is based on the application of an electric field of short duration and high voltage to the cells, forming reversible pores through which molecules can enter the cell. In this work, we describe the optimization of a protocol for the electroporation of K562 cells involving the combination of electric field, resistance and capacitance values. Using RPMI 1640 as pulsing buffer and 30 mug of pEGFP-N1 plasmid, 875 V cm(-1), 500 muF and infinite resistance, we achieved transfection rates of 82.41 +/- 3.03%, with 62.89 +/- 2.93% cell viability, values higher than those reported in the literature. Analyzing cell cycle after electroporation, with three different electric field conditions, we observed that in a heterogeneous population of cells, viability of G(1) cells is less affected by electroporation than that of cells in late S and G(2)/M phases. We also observed that efficiency of electroporation can be improved using the DNAse inhibitor Zn, immediately after the pulse. These results can represent a significant improvement of current methods of electroporation of animal and plant cells.

17.
São Paulo med. j ; 126(2): 75-81, Mar. 2008. ilus, tab
Artículo en Inglés | LILACS | ID: lil-484513

RESUMEN

CONTEXT AND OBJECTIVES: There are few studies concerning bone marrow mononuclear cell (BMMC) transplantation in cases of nonischemic dilated cardiomyopathy. This study describes a novel technique of BMMC transplantation and the results up to one year after the procedure. DESIGN AND SETTING: This was a case series to evaluate the safety and viability of the procedure, at Instituto de Cardiologia do Rio Grande do Sul. METHODS: Nine patients with symptomatic dilated cardiomyopathy, functional class III/IV and left ventricular ejection fraction (LVEF) < 35 percent received BMMC (9.6 ± 2.6 x 107 cells) at 20 sites in the ventricular wall, by means of thoracotomy of length 5 cm in the fifth left intercostal space. Echocardiograms and nuclear magnetic resonance (NMR) were performed. RESULTS: There were no major complications. The functional class results for the first six patients (preoperatively and at two, four, eight and twelve-month follow-ups, respectively) were: [IV-2, III-4] to [I-5, II-1] to [I-3, II-3] to [I-2, II-3] and [I-2, II-3]. Echocardiograms showed LVEF: 25.9 ± 8.2; 32.9 ± 10.4; 29.4 ± 7.2; 25.1 ± 7.9; 25.4 ± 6.8 percent (p = 0.023); and percent left ventricular (LV) fiber shortening: 12.6 ± 4.4; 16.4 ± 5.4; 14.3 ± 3.7; 12.1 ± 4.0; 12.2 ± 3.4 percent (p = 0.021). LV performance variation seen on NMR was non-significant. CONCLUSION: Intramyocardial transplantation of BMMC in dilated cardiomyopathy cases is feasible and safe. There were early improvements in symptoms and LV performance. Medium-term evaluation revealed regression of LV function, although maintaining improved functional class.


CONTEXTO E OBJETIVO: Há pouco estudos avaliando o transplante de células mononucleares da medula óssea (CMMO) na miocardiopatia dilatada não-isquêmica. O presente estudo descreve uma técnica de implante intramiocárdico de CMMO por mini-toracomia e resultados com até um ano de acompanhamento. TIPO DE ESTUDO E LOCAL: Série casos para avaliar segurança e viabilidade do procedimento, no Instituto de Cardiologia do Rio Grande do Sul. MÉTODOS: Nove pacientes com miocardiopatia dilatada, em classe funcional III/IV e fração de ejeção do ventrículo esquerdo (FEVE) < 35 por cento receberam CMMO (média 9,6 ± 2,6 x 107 células) em 20 pontos da parede livre do ventrículo esquerdo, através de toracotomia de 5 cm no quinto espaço intercostal esquerdo. Foram realizados ecocardiograma e ressonância nuclear magnética (RNM). RESULTADOS: Não ocorreram complicações maiores. Os resultados pré-operatórios aos 2, 4, 8 e 12 meses de acompanhamento dos seis primeiros pacientes são: classe funcional: IV-2, III-4 para I-5, II-1 para I-3, II-3 para I-2, II-3 e I-2, II-3. Ecocardiograma: FEVE = 25.9 ± 8.2, 32.9 ± 10.4, 29.4 ± 7.2, 25.1 ± 7.9, 25.4 ± 6.8 por cento (p = 0.023); Fração de encurtamento do ventrículo esquerdo (VE) = 12.6 ± 4.4, 16.4 ± 5.4, 14.3 ± 3.7, 12.1 ± 4.0, 12.2 ± 3.4 por cento (p = 0.021). RNM demonstrou diferenças discretas, não significativas. CONCLUSÕES: O implante intramiocárdico de células-tronco na miocardiopatia dilatada é viável e seguro. Houve melhora precoce nos sintomas e na performance de VE. Avaliação a médio prazo demonstrou regressão da função VE, mantendo, contudo, a melhora na qualidade de vida e na classe funcional.


Asunto(s)
Femenino , Humanos , Masculino , Persona de Mediana Edad , Trasplante de Médula Ósea/métodos , Cardiomiopatía Dilatada/cirugía , Trasplante de Células Madre/métodos , Toracotomía/métodos , Estudios de Factibilidad , Inmunofenotipificación , Espectroscopía de Resonancia Magnética , Volumen Sistólico/fisiología , Factores de Tiempo , Trasplante Autólogo , Resultado del Tratamiento , Función Ventricular Izquierda/fisiología
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