310 research outputs found
The Role of Natriuretic peptides in Renovascular Hypertension and its correlation with the Evolution of Myocardial Hypertrophy
The interactions between pressure and volume overload that occur in hypertension lead to different patterns of cardiac hypertrophy and to increase in natriuretic peptides (NPs). The profiles of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) synthesis and secretion have been investigated in models of hypertension. However, the different evolution of these profiles during the acute and chronic periods of pressure overload-induced cardiac hypertrophy is still unknown. For this reason, we studied one-kidney, one clip model using Sprague-Dawley rats at weeks 2, 4, 6 and 12 and correlated the evolution of these profiles with cardiac hypertrophy and hypertension. We observed a positive correlation between blood pressure elevation and the degree of cardiac hypertrophy, with a time-dependent increase in both parameters from week 2. Levels of BNP expression showed an early increase after 2 weeks of treatment while ANP increased significantly after 6 weeks. Yet, the increase in ANP expression was gradual, allowing its correlation with hypertrophy and hypertension. The NP expression has a differential response in the early stages of the development of hypertrophy induced by the renovascular model, with an early increase in BNP expression. Once hypertrophy develops, BNP expression is no longer specific and the increase of both NPs depends on and correlates with the degree of cardiac hypertrophy.Fil: Cerrudo, Carolina Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Cavallero, Carmen Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Rodríguez Fermepin, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Hertig, Cecilia Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Fernandez, Belisario Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentin
Natriuretic Peptides Synthesis and Secretion Profiles during the Evolution of Cardiac Hypertrophy in DOCA-Salt Hypertensive Rats
Durante el desarrollo de la hipertensión arterial, las interacciones entre las sobrecargas de presión y de volumen conducen a diferentes patrones de hipertrofia cardíaca y a un aumento de los péptidos natriuréticos (PN). Los perfiles de síntesis y secreción de ANP y BNP se han investigado en modelos de hipertensión arterial; sin embargo, aún no se ha estudiado la evolución diferencial de estos perfiles durante períodos agudos y crónicos de la hipertrofia cardíaca producida por sobrecarga de volumen. Por este motivo estudiamos ratas Sprague- Dawley con el modelo DOCA-sal a las 2, 4, 6 y 12 semanas, correlacionando la evolución de dichos perfiles con la hipertrofia cardíaca y la hipertensión arterial.
El grado de hipertrofia cardíaca se correlacionó positivamente con la expresión del ANP en el ventrículo izquierdo y con los niveles de ANP en plasma. La expresión del ANP aumentó a las 4 semanas de tratamiento, mientras que la de BNP se incrementó recién a las 6 semanas. Asimismo, el BNP plasmático se incrementó sólo en el grupo con 12 semanas de tratamiento, mientras que el ANP plasmático mostró un aumento a partir de las 2 semanas de tratamiento. Durante el desarrollo de la hipertrofia cardíaca producida en el modelo DOCA-sal, la síntesis y la secreción de los PN responden en forma diferencial, con incremento precoz del ANP. Además, el aumento de éste superó al de BNP en todos los grupos DOCA-sal, lo que permitiría considerar al ANP como un marcador más específico de la sobrecarga de volumen.The interactions between pressure and volume overload that occur in hypertension lead to different patterns of cardiac hypertrophy and to increase in natriuretic peptides (NPs). The profiles of ANP and BNP synthesis and secretion have been investigated in models of hypertension; however, the different evolution of these profiles during the acute and chronic periods of pressure overload-induced cardiac hypertrophy is still unknown. For this reason, we studied DOCA-salt treated Sprague-Dawley rats at weeks 2, 4, 6 and 12 and correlated the evolution of these profiles with cardiac hypertrophy and hypertension.
Cardiac hypertrophy had a positive correlation with ANP expression in the left ventricle and with ANP plasma levels. BNP expression increased after 4 weeks of treatment while ANP increased significantly after 6 weeks. In addition, BNP plasma levels increased only in the group treated for 12 weeks, while ANP plasma levels increased from week 2. NP secretion has a differential response in the early stages of the development of cardiac hypertrophy induced by the DOCA-salt model, with an early increase in ANP. As ANP levels were exceeded to those of BNP in all the DOCA-salt groups, ANP might be considered a more specific marker of volume overloadFil: Cerrudo, Carolina Susana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Rodríguez Fermepin, Martin. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Cavallero, Carmen Susana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Saucedo, Silvia L.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Hertig, Cecilia Margarita. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Fernandez, Belisario Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentin
Cardiac Natriuretic Peptide Profiles in Chronic Hypertension by Single or Sequentially Combined Renovascular and DOCA-Salt Treatments
The involvement of natriuretic peptides was studied during the hypertrophic remodeling transition mediated by sequential exposure to chronic hemodynamic overload. We induced hypertension in rats by pressure (renovascular) or volume overload (DOCA-salt) during 6 and 12 weeks of treatment. We also studied the consecutive combination of both models in inverse sequences: RV 6 weeks/DS 6 weeks and DS 6 weeks/RV 6 weeks. All treated groups developed hypertension. Cardiac hypertrophy and left ventricular ANP gene expression were more pronounced in single DS than in single RV groups. BNP gene expression was positively correlated with left ventricular hypertrophy only in RV groups, while ANP gene expression was positively correlated with left ventricular hypertrophy only in DS groups. Combined models exhibited intermediate values between those of single groups at 6 and 12 weeks. The latter stimulus associated to the second applied overload is less effective than the former to trigger cardiac hypertrophy and to increase ANP and BNP gene expression. In addition, we suggest a correlation of ANP synthesis with volume overload and of BNP synthesis with pressure overload-induced hypertrophy after a prolonged treatment. Volume and pressure overload may be two mechanisms, among others, involved in the differential regulation of ANP and BNP gene expression in hypertrophied left ventricles. Plasma ANP levels reflect a response to plasma volume increase and volume overload, while circulating BNP levels seem to be regulated by cardiac BNP synthesis and ventricular hypertrophy.Fil: Cerrudo, Carolina Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; ArgentinaFil: Cavallero, Carmen Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; ArgentinaFil: Rodríguez Fermepin, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; ArgentinaFil: González, Germán Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Patología; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiopatología Cardiovascular; ArgentinaFil: Donato, Pablo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Patología; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiopatología Cardiovascular; ArgentinaFil: Kouyoumdzian, Nicolás Martín. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional. - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiologicas "prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones En Medicina Traslacional.; ArgentinaFil: Gelpi, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiopatología Cardiovascular; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Patología; ArgentinaFil: Hertig, Cecilia Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Choi, Marcelo Roberto. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Histología y Biología Celular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional - Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas "Prof. Dr. Alberto C. Taquini". Instituto Alberto C. Taquini de Investigaciones en Medicina Traslacional; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentina. Instituto Universidad de la Fundación "Héctor Barceló"; ArgentinaFil: Fernandez, Belisario Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentina. Instituto Universidad de la Fundación "Héctor Barceló"; Argentin
Time domain automatic focusing of an Applebaum array
Summary form only given, as follows. It has been shown that the performance of the automatic focusing technique (AFT) is maintained when the scanned frequencies are sent simultaneously in a wide-band signal. As a result, this procedure provides the AFT with additional capabilities while removing its drawback
Imatinib inhibits proliferation of Ewing tumor cells mediated by the stem cell factor/KIT receptor pathway, and sensitizes cells to vincristine and doxorubicin-induced apoptosis
Purpose and Experimental Design: The stem cell factor/
KIT receptor loop may represent a novel target for molecular-
based therapies of Ewing tumor. We analyzed the in
vitro impact of KIT blockade by imatinib in Ewing tumor
cell lines.
Results: KIT expression was detected in 4 of 4 Ewing
tumor cell lines and in 49 of 110 patient samples (44.5%) by
immunohistochemistry and/or Western blot analysis. KIT
expression was stronger in Ewing tumors showing EWSFLI1
nontype 1 fusions. Despite absence of c-kit mutations,
constitutive and ligand-inducible phosphorylation of KIT
was found in all tumor cell lines, indicating an active receptor.
Treatment with KIT tyrosine kinase inhibitor imatinib
(0.5–20 M) induced down-regulation of KIT phosphorylation
and dose response inhibition of cell proliferation (IC50,
12–15 M). However, imatinib administered alone at doses
close to IC50 for growth inhibition (10 M) did not induce a
significant increase in apoptosis. We then analyzed if blockade
of KIT loop through imatinib (10 M) was able to
increase the antitumor in vitro effect of doxorubicin (DXR)and vincristine (VCR), drugs usually used in Ewing tumor
treatment. Addition of imatinib decreased in 15–20 and
15–36% of the proliferative rate of Ewing tumor cells exposed
to DXR and VCR, respectively, and increased in 15
and 30% of the apoptotic rate of Ewing tumor cells exposed
to the same drugs.
Conclusions: Inhibition of Ewing tumor cell proliferation
by imatinib is mediated through blockade of KIT receptor
signaling. Inhibition of KIT increases sensitivity of
these cells to DXR and VCR. This study supports a potential
role for imatinib in the treatment of Ewing tumor
Transcription factors Sp1 and p73 control the expression of the proapoptotic protein NOXA in the response of testicular embryonal carcinoma cells to cisplatin
Testicular germ cell tumors (TGCTs) are highly responsive to and curable by cisplatin-based chemotherapy even in advanced stages. We have studied the molecular mechanisms involved in the induction of apoptosis in response to cisplatin, and found that proapoptotic Noxa is transcriptionally up-regulated following cisplatin exposure, even in the absence of p53, in NTERA2 cisplatin-sensitive cells but not in 1411HP-resistant cells. Blockade of Noxa reduced the apoptotic response of embryonal carcinoma (EC) NTERA2 cells to cisplatin. A detailed analysis of the Noxa promoter revealed that p73 and Sp1-like factors, Sp1 and KLF6, played key roles in the transcriptional control of this gene. Overexpression of TAp73 induced Noxa whereas the dominant negative isoform ΔNp73, reduced the levels of Noxa after cisplatin exposure in NTERA2 and 2102EP. Interestingly, down-regulation of Sp1 increased Noxa expression in response to cisplatin. However, blockade of KLF6 decreased cisplatin-induced up-regulation of Noxa in EC cell lines. In addition, tissue microarray analyses of TGCTs revealed that expression of Noxa correlates with good clinical prognosis in patients with embryonal carcinoma. Thus, our data show the transcriptional network that regulates Noxa in EC cells, which is key for their apoptotic response to cisplatin-based chemotherapy, and propose Noxa as a predictive factor of therapeutic response
Desmoglein-4 deficiency exacerbates psoriasiform dermatitis in rats while psoriasis patients displayed a decreased gene expression of DSG4
Desmogleins are involved in cell adhesion conferring structural skin integrity. However, their role in inflammation has been barely studied, and whether desmoglein-4 modulates psoriasis lesions is completely unknown. In this study, we assessed the impact of desmoglein-4 deficiency on the severity of imiquimod (IMQ)-induced skin inflammation and psoriasiform lesions. To this end, desmoglein-4−/− Oncins France Colony A (OFA) with Sprague–Dawley (SD) genetic background were used. Additionally, human RNA-Seq datasets from psoriasis (PSO), atopic dermatitis (AD), and a healthy cohort were analyzed to obtain a desmosome gene expression overview. OFA rats displayed an intense skin inflammation while SD showed only mild inflammatory changes after IMQ treatment. We found that IMQ treatment increased CD3+ T cells in skin from both OFA and SD, being higher in desmoglein-4-deficient rats. In-depth transcriptomic analysis determined that PSO displayed twofold less DSG4 expression than healthy samples while both, PSO and AD showed more than three-fold change expression of DSG3 and DSC2 genes. Although underlying mechanisms are still unknown, these results suggest that the lack of desmoglein-4 may contribute to immune-mediated skin disease progression, promoting leukocyte recruitment to skin. Although further research is needed, targeting desmoglein-4 could have a potential impact on designing new biomarkers for skin diseases.Fil: Moreno Sosa, María Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Sánchez, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Pietrobon, Elisa Olivia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Fernandez Muñoz, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Zoppino, Felipe Carlos Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Neira, Flavia Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Germano, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Innocenti Badano, Alicia Carolina. Gobierno de la Provincia de Mendoza. Hospital Luis Lagomaggiore.; ArgentinaFil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Valdez, Susana Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Mackern Oberti, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentin
LXR Nuclear receptors are transcriptional regulators of dendritic cell chemotaxis
The liver X receptors (LXRs) are ligand-activated nuclear receptors with established roles in the maintenance of lipid homeostasis in multiple tissues. LXRs exert additional biological functions as negative regulators of inflammation, particularly in macrophages. However, the transcriptional responses controlled by LXRs in other myeloid cells, such as dendritic cells (DCs), are still poorly understood. Here we used gain- and loss-of-function models to characterize the impact of LXR deficiency on DC activation programs. Our results identified an LXR-dependent pathway that is important for DC chemotaxis. LXR-deficient mature DCs are defective in stimulus-induced migration in vitro and in vivo. Mechanistically, we show that LXRs facilitate DC chemotactic signaling by regulating the expression of CD38, an ectoenzyme important for leukocyte trafficking. Pharmacological or genetic inactivation of CD38 activity abolished the LXR-dependent induction of DC chemotaxis. Using the low-density lipoprotein receptor-deficient (LDLR−/−) LDLR−/− mouse model of atherosclerosis, we also demonstrated that hematopoietic CD38 expression is important for the accumulation of lipid-laden myeloid cells in lesions, suggesting that CD38 is a key factor in leukocyte migration during atherogenesis. Collectively, our results demonstrate that LXRs are required for the efficient emigration of DCs in response to chemotactic signals during inflammation
Prediction of poor outcome in clostridioides difficile infection: A multicentre external validation of the toxin B amplification cycle
Producción CientíficaClassification of patients according to their risk of poor outcomes in Clostridioides difficile infection (CDI) would enable implementation of costly new treatment options in a subset of patients at higher risk of poor outcome. In a previous study, we found that low toxin B amplification cycle thresholds (Ct) were independently associated with poor outcome CDI. Our objective was to perform a multicentre external validation of a PCR-toxin B Ct as a marker of poor outcome CDI. We carried out a multicentre study (14 hospitals) in which the characteristics and outcome of patients with CDI were evaluated. A subanalysis of the results of the amplification curve of real-time PCR gene toxin B (XpertTM C. difficile) was performed. A total of 223 patients were included. The median age was 73.0 years, 50.2% were female, and the median Charlson index was 3.0. The comparison of poor outcome and non–poor outcome CDI episodes revealed, respectively, the following results: median age (years), 77.0 vs 72.0 (p = 0.009); patients from nursing homes, 24.4% vs 10.8% (p = 0.039); median leukocytes (cells/μl), 10,740.0 vs 8795.0 (p = 0.026); and median PCR-toxin B Ct, 23.3 vs 25.4 (p = 0.004). Multivariate analysis showed that a PCR-toxin B Ct cut-off <23.5 was significantly and independently associated with poor outcome CDI (p = 0.002; OR, 3.371; 95%CI, 1.565–7.264). This variable correctly classified 68.5% of patients. The use of this microbiological marker could facilitate early selection of patients who are at higher risk of poor outcome and are more likely to benefit from newer and more costly therapeutic options
Search for coherent elastic neutrino-nucleus scattering at a nuclear reactor with CONNIE 2019 data
The Coherent Neutrino-Nucleus Interaction Experiment (CONNIE) is taking data
at the Angra 2 nuclear reactor with the aim of detecting the coherent elastic
scattering of reactor antineutrinos with silicon nuclei using charge-coupled
devices (CCDs). In 2019 the experiment operated with a hardware binning applied
to the readout stage, leading to lower levels of readout noise and improving
the detection threshold down to 50 eV. The results of the analysis of 2019 data
are reported here, corresponding to the detector array of 8 CCDs with a
fiducial mass of 36.2 g and a total exposure of 2.2 kg-days. The difference
between the reactor-on and reactor-off spectra shows no excess at low energies
and yields upper limits at 95% confidence level for the neutrino interaction
rates. In the lowest-energy range, 50-180 eV, the expected limit stands at 34
(39) times the standard model prediction, while the observed limit is 66 (75)
times the standard model prediction with Sarkis (Chavarria) quenching factors.Comment: 23 pages, 14 figure
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