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1.
Angiogenesis ; 27(2): 211-227, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38294582

RESUMEN

Heterozygous activin receptor-like kinase 1 (ALK1) mutations are associated with two vascular diseases: hereditary hemorrhagic telangiectasia (HHT) and more rarely pulmonary arterial hypertension (PAH). Here, we aimed to understand the impact of ALK1 mutations on BMP9 and BMP10 transcriptomic responses in endothelial cells. Endothelial colony-forming cells (ECFCs) and microvascular endothelial cells (HMVECs) carrying loss of function ALK1 mutations were isolated from newborn HHT and adult PAH donors, respectively. RNA-sequencing was performed on each type of cells compared to controls following an 18 h stimulation with BMP9 or BMP10. In control ECFCs, BMP9 and BMP10 stimulations induced similar transcriptomic responses with around 800 differentially expressed genes (DEGs). ALK1-mutated ECFCs unexpectedly revealed highly similar transcriptomic profiles to controls, both at the baseline and upon stimulation, and normal activation of Smad1/5 that could not be explained by a compensation in cell-surface ALK1 level. Conversely, PAH HMVECs revealed strong transcriptional dysregulations compared to controls with > 1200 DEGs at the baseline. Consequently, because our study involved two variables, ALK1 genotype and BMP stimulation, we performed two-factor differential expression analysis and identified 44 BMP9-dysregulated genes in mutated HMVECs, but none in ECFCs. Yet, the impaired regulation of at least one hit, namely lunatic fringe (LFNG), was validated by RT-qPCR in three different ALK1-mutated endothelial models. In conclusion, ALK1 heterozygosity only modified the BMP9/BMP10 regulation of few genes, including LFNG involved in NOTCH signaling. Future studies will uncover whether dysregulations in such hits are enough to promote HHT/PAH pathogenesis, making them potential therapeutic targets, or if second hits are necessary.


Asunto(s)
Hipertensión Arterial Pulmonar , Telangiectasia Hemorrágica Hereditaria , Adulto , Recién Nacido , Humanos , Células Endoteliales/metabolismo , Factor 2 de Diferenciación de Crecimiento/genética , Factor 2 de Diferenciación de Crecimiento/metabolismo , Hipertensión Arterial Pulmonar/metabolismo , Telangiectasia Hemorrágica Hereditaria/genética , Telangiectasia Hemorrágica Hereditaria/metabolismo , Proteínas Morfogenéticas Óseas/genética , Mutación/genética , Perfilación de la Expresión Génica , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo
2.
Arch. argent. pediatr ; 119(6): 414-418, dic. 2021. tab, ilus
Artículo en Inglés, Español | LILACS, BINACIS | ID: biblio-1342853

RESUMEN

El compromiso renal en los pacientes pediátricos con enfermedad por el coronavirus 2019 (COVID-19, por su sigla en inglés) varía entre el 10 % y el 80 %. Dado que existe limitada información sobre su pronóstico, se realizó este estudio con el objetivo de describir la evolución en el corto plazo de pacientes a quienes se les detectó compromiso renal durante la internación por COVID-19. Estudio observacional y transversal que incluyó pacientes entre 1 mes y 18 años con COVID-19 con compromiso renal. Se excluyeron aquellos con patología renal conocida. Se identificaron 27 pacientes con afectación renal, en 14 de ellos se pudo realizar seguimiento para estudiar la evolución renal luego de 3 meses del diagnóstico. Todos habían normalizado los niveles de creatinina plasmática durante la internación y al momento del control ambulatorio, realizado a los 145 días (92-193), todos se encontraban normotensos y con hallazgos urinarios normales, excepto uno que persistía con microhematuria. La evolución fue favorable; la mayoría de los pacientes presentaron remisión completa del compromiso renal.


Renal involvement among pediatric patients with coronavirus disease 2019 (COVID-19) ranges between 10 % and 80 %.Given the limited information about its prognosis, the objective of this study was to describe the short-term course of patients in whom renal involvement was detected during hospitalization due to COVID-19. This was an observational, cross-sectional study in patients aged 1 month to 18 years who had COVID-19 and renal involvement. Those with a known kidney disease were excluded. A total of 27 patients with renal involvement were identified; 14 of them were followed-up to study their disease course for 3 months after diagnosis. All of the patients had achieved normal plasma creatinine levels during hospitalization and, at the time of outpatient follow-up, which took place 145 days (92-193) later, all had normal blood pressure and urinary values, except for 1 patient who continued with microscopic hematuria. Course was favorable; in most patients, renal involvement had fully resolved.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Adolescente , Lesión Renal Aguda , COVID-19 , Pronóstico , Estudios Transversales , SARS-CoV-2 , Hematuria
3.
Arch Argent Pediatr ; 119(6): 414-420, 2021 12.
Artículo en Inglés, Español | MEDLINE | ID: mdl-34813235

RESUMEN

Renal involvement among pediatric patients with coronavirus disease 2019 (COVID-19) ranges between 10% and 80%. Given the limited information about its prognosis, the objective of this study was to describe the short-term course of patients in whom renal involvement was detected during hospitalization due to COVID-19. This was an observational, cross-sectional study in patients aged 1 month to 18 years who had COVID-19 and renal involvement. Those with a known kidney disease were excluded. A total of 27 patients with renal involvement were identified; 14 of them were followed-up to study their disease course for 3 months after diagnosis. All of the patients had achieved normal plasma creatinine levels during hospitalization and, at the time of outpatient follow-up, which took place 145 days (92-193) later, all had normal blood pressure and urinary values, except for 1 patient who continued with microscopic hematuria. Course was favorable; in most patients, renal involvement had fully resolved.


El compromiso renal en los pacientes pediátricos con enfermedad por el coronavirus 2019 (COVID-19, por su sigla en inglés) varía entre el 10 % y el 80 %. Dado que existe limitada información sobre su pronóstico, se realizó este estudio con el objetivo de describir la evolución en el corto plazo de pacientes a quienes se les detectó compromiso renal durante la internación por COVID-19. Estudio observacional y transversal que incluyó pacientes entre 1 mes y 18 años con COVID-19 con compromiso renal. Se excluyeron aquellos con patología renal conocida. Se identificaron 27 pacientes con afectación renal, en 14 de ellos se pudo realizar seguimiento para estudiar la evolución renal luego de 3 meses del diagnóstico. Todos habían normalizado los niveles de creatinina plasmática durante la internación y al momento del control ambulatorio, realizado a los 145 días (92-193), todos se encontraban normotensos y con hallazgos urinarios normales, excepto uno que persistía con microhematuria. La evolución fue favorable; la mayoría de los pacientes presentaron remisión completa del compromiso renal.


Asunto(s)
Lesión Renal Aguda , COVID-19 , Niño , Hematuria , Humanos , Pronóstico , SARS-CoV-2
4.
Hum Mol Genet ; 29(13): 2134-2147, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32436947

RESUMEN

Olfactory dysfunction and altered neurogenesis are observed in several neurodegenerative disorders including Huntington disease (HD). These deficits occur early and correlate with a decline in global cognitive performance, depression and structural abnormalities of the olfactory system including the olfactory epithelium, bulb and cortices. However, the role of olfactory system dysfunction in the pathogenesis of HD remains poorly understood and the mechanisms underlying this dysfunction are unknown. We show that deficits in odour identification, discrimination and memory occur in HD individuals. Assessment of the olfactory system in an HD murine model demonstrates structural abnormalities in the olfactory bulb (OB) and piriform cortex, the primary cortical recipient of OB projections. Furthermore, a decrease in piriform neuronal counts and altered expression levels of neuronal nuclei and tyrosine hydroxylase in the OB are observed in the YAC128 HD model. Similar to the human HD condition, olfactory dysfunction is an early phenotype in the YAC128 mice and concurrent with caspase activation in the murine HD OB. These data provide a link between the structural olfactory brain region atrophy and olfactory dysfunction in HD and suggest that cell proliferation and cell death pathways are compromised and may contribute to the olfactory deficits in HD.


Asunto(s)
Enfermedad de Huntington/genética , Neuronas/metabolismo , Bulbo Olfatorio/metabolismo , Mucosa Olfatoria/metabolismo , Animales , Atrofia/metabolismo , Atrofia/patología , Encéfalo/metabolismo , Encéfalo/patología , Muerte Celular/genética , Proliferación Celular/genética , Modelos Animales de Enfermedad , Humanos , Enfermedad de Huntington/patología , Ratones , Neurogénesis/genética , Neuronas/patología , Bulbo Olfatorio/patología , Mucosa Olfatoria/patología , Transducción de Señal/genética , Olfato/genética
5.
Neurobiol Dis ; 125: 219-231, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30738141

RESUMEN

Olfactory dysfunction is observed in several neurological disorders, including Huntington disease (HD), and correlates with global cognitive performance, depression and degeneration of olfactory regions in the brain. Despite clear evidence demonstrating olfactory dysfunction in HD patients, only limited details are available in murine models and the underlying mechanisms are unknown. In order to determine if alterations in the olfactory bulb (OB) are observed in HD we assessed OB weight or area from 3 to 12 months of age in the BACHD transgenic lines (TG5 and TG9). A significant decrease in the OB was observed at 6 and 12 months of age compared to WT. We also detected increased mRNA and protein expression of mutant huntingtin (mHTT) in the OB of TG5 compared to TG9 at specific ages. Despite the higher expression of mHTT in the TG5 OBs, there was increased nuclear accumulation of mHTT in the OB of TG9 compared to WT and TG5 rats. As we observed atrophy of the OB in the BACHD rats we assessed for caspase activation, a known mechanism underlying the cell death observed in HD. We characterized caspase-3, -6, -8 and - 9 mRNA and protein expression levels in the OB of the BACHD transgenic lines at 3, 6 and 12 months of age. Alterations in caspase mRNA and protein expression were detected in the TG5 and TG9 lines. However, the changes observed in the mRNA and protein levels are in some cases discordant, suggesting that the caspase protein modifications detected may be more attributable to post-translational modifications. The caspase activation studies support that cell death may be increased in the rodent HD OB and further our understanding of the olfactory dysfunction and the role of caspases in the pathogenesis of HD.


Asunto(s)
Caspasas/metabolismo , Enfermedad de Huntington/complicaciones , Trastornos del Olfato/etiología , Bulbo Olfatorio/enzimología , Bulbo Olfatorio/patología , Animales , Atrofia/etiología , Atrofia/patología , Modelos Animales de Enfermedad , Activación Enzimática/fisiología , Humanos , Proteína Huntingtina/genética , Enfermedad de Huntington/enzimología , Enfermedad de Huntington/patología , Trastornos del Olfato/enzimología , Trastornos del Olfato/patología , Ratas , Ratas Transgénicas
6.
CPT Pharmacometrics Syst Pharmacol ; 6(3): 197-207, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28145085

RESUMEN

The combination of aztreonam-avibactam is active against multidrug-resistant Enterobacteriaceae that express metallo-ß-lactamases. A complex synergistic interaction exists between aztreonam and avibactam bactericidal activities that have not been quantitatively explored. A two-state semimechanistic pharmacokinetic/pharmacodynamic (PK/PD) logistic growth model was developed to account for antimicrobial activities in the combination of bacteria-mediated degradation of aztreonam and the inhibition of aztreonam degradation by avibactam. The model predicted that changing regimens of 2 g aztreonam plus 0.375 and 0.6 g avibactam as a 1-hour infusion were qualitatively similar to that observed from in vivo murine thigh infection and hollow-fiber infection models previously reported in the literature with 24-hour log kill ≥1. The current approach to characterize the effect of avibactam in enhancing aztreonam activity from time-kill study was accomplished by shifting the half-maximal effective concentration (EC50 ) of aztreonam in increasing avibactam concentration using a nonlinear equation as a function of avibactam concentration, providing a framework for translational predictions.


Asunto(s)
Compuestos de Azabiciclo/administración & dosificación , Aztreonam/administración & dosificación , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Modelos Biológicos , Animales , Antibacterianos/administración & dosificación , Farmacorresistencia Bacteriana Múltiple/fisiología , Quimioterapia Combinada , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Predicción , Humanos , Ratones , Pruebas de Sensibilidad Microbiana/métodos , Infecciones por Pseudomonas/tratamiento farmacológico , Inhibidores de beta-Lactamasas/administración & dosificación
7.
Neurosci Lett ; 606: 53-9, 2015 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-26321151

RESUMEN

Exposure to the natural pesticide, rotenone, a potent mitochondrial toxin, leads to degeneration in striatal nerve terminals and nigral neurons. Rotenone-induced behavioral, neurochemical and neuropathological changes in rats mimic those observed in Parkinson's disease (PD). Here, protective effects of acetyl-L-carnitine (ALC) in the brain dopaminergic toxicity after a prolonged exposure to rotenone were evaluated using electrophysiological and immunolabeling methods. Adult, male Sprague-Dawley rats were injected i.p. with rotenone alone (1 mg/kg) or rotenone with ALC (either 10 or 100 mg/kg; ALC10 or ALC100, respectively) once daily on days 1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24, 26, 29, 31, 33 and 37. Control rats received either 100mg/kg ALC or vehicle (30% Solutol HS 15 in 0.9% saline) injections. Animals were weighed on injection days and monitored daily. Motor nerve conduction velocity (MCV) was assessed within two days after treatment using compound muscle action potentials (CMAP) detected from the tail muscle through surface receiver electrodes installed around the distal part of the tail. Rats were perfused immediately after testing with 4% paraformaldehyde and immunohistochemical analysis of dopamine transporter (DAT), tyrosine hydroxylase (TH), glial fibrillary acidic protein (GFAP), and microglial CD11b marker was performed in the caudate-putamen (CPu) and the substantia nigra pars compacta (SNc) in order to estimate dopaminergic neuronal and transporter damage. Additionally, effects of ALC on preventing microglial or astrocytic hypertrophy were also evaluated. In rats exposed to rotenone and rotenone/ACL10, a significant increases in both proximal (S1) and distal (S2) motor latency and a decrease in MCV were detected in tail nerves (p<0.05). The conduction parameters in rats co-treated with rotenone/ACL100 were not different from control. It was found that 100 mg/kg ALC prevented loss of TH and a decline of DAT level in the midbrain and also prevented the activation of both microglia and astroglia after rotenone treatment. Data indicate neuroprotective effects of ALC in rotenone-evoked dopaminergic neurotoxicity.


Asunto(s)
Acetilcarnitina/farmacología , Dopamina/metabolismo , Fármacos Neuroprotectores/farmacología , Plaguicidas/toxicidad , Rotenona/toxicidad , Potenciales de Acción , Animales , Núcleo Caudado/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Masculino , Microglía/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/inervación , Conducción Nerviosa , Putamen/metabolismo , Ratas Sprague-Dawley , Sustancia Negra/metabolismo , Cola (estructura animal)/efectos de los fármacos , Cola (estructura animal)/inervación , Tirosina 3-Monooxigenasa/metabolismo
8.
Curr Neuropharmacol ; 9(1): 236-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21886596

RESUMEN

Advances in computer technology have allowed quantification of the electroencephalogram (EEG) and expansion of quantitative EEG (qEEG) analysis in neurophysiology, as well as clinical neurology, with great success. Among the variety of techniques in this field, frequency (spectral) analysis using Fast Fourier Transforms (FFT) provides a sensitive tool for time-course studies of different compounds acting on particular neurotransmitter systems. Studies presented here include Electrocorticogram (ECoG) analysis following exposure to a glutamic acid analogue - domoic acid (DOM), psychoactive indole alkaloid - ibogaine, as well as cocaine and gamma-hydroxybutyrate (GHB). The ECoG was recorded in conscious rats via a tether and swivel system. The EEG signal frequency analysis revealed an association between slow-wave EEG activity delta and theta and the type of behavioral seizures following DOM administration. Analyses of power spectra obtained in rats exposed to cocaine alone or after pretreatment with ibogaine indicated the contribution of the serotonergic system in ibogaine mediated response to cocaine (increased power in alpha(1) band). Ibogaine also lowered the threshold for cocaine-induced electrographic seizures (increased power in the low-frequency bands, delta and theta). Daily intraperitoneal administration of cocaine for two weeks was associated with a reduction in slow-wave ECoG activity 24 hrs following the last injection when compared with controls. Similar decreased cortical activity in low-frequency bands observed in chronic cocaine users has been associated with reduced metabolic activity in the frontal cortex. The FFT analyses of power spectra relative to baseline indicated a significant energy increase over all except beta(2) frequency bands following exposure to 400 and 800 mg/kg GHB. The EEG alterations detected in rats following exposure to GHB resemble absence seizures observed in human petit mal epilepsy. Spectral analysis of the EEG signals combined with behavioral observations may prove to be a useful approach in studying chronic exposure to drugs of abuse and treatment of drug dependence.

9.
Neuroscience ; 147(4): 1114-8, 2007 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-17590518

RESUMEN

Aging is a significant risk factor for developing epilepsy. The mechanisms underlying age-related increase in seizure susceptibility and resultant injury remain unknown. Oxidative stress is an important mechanism that contributes to diverse age-related disorders. Whether age-related increased seizure susceptibility is accompanied by increased oxidative stress remains unknown. The goal of this study was to determine if aging per se increases the susceptibility of rats to kainate-induced behavioral seizures and oxidative stress. Adult (3-4 month-old) and aging (18-19 month-old) Sprague-Dawley rats were administered a single low dose of kainate (5 mg/kg, s.c.) or saline. Behavioral seizures were monitored in all four groups for a period for a period of approximately 6 h. Oxidative stress (8-hydroxy-2'deoxyguanosine/2-deoxyguanosine; 8OHdG/2dG) was assessed 24 h following kainate injection. Stereological assessment of cell counts was performed in hippocampal tissue 7 days following kainate injection. In adult rats, administration of the low dose of kainate did not produce significant behavioral seizures, oxidative stress or cell loss. However, aging rats exhibited intense behavioral seizures consistent with status epilepticus following the low dose of kainate. In aging rats, kainate produced a significant increase in oxidative DNA damage (8OHdG/2dG) and neuronal loss in cornu ammonis regions 3 and 1 (CA3 and CA1), but not dentate gyrus compared with both age-matched controls and adult kainate-treated rats. These data suggest that the process of aging per se increases kainate-induced seizure susceptibility, oxidative stress and hippocampal pyramidal cell loss.


Asunto(s)
Envejecimiento/fisiología , Neuronas/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Convulsiones/patología , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Conducta Animal/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Relación Dosis-Respuesta a Droga , Ácido Kaínico , Masculino , Neuronas/metabolismo , Estrés Oxidativo/fisiología , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Convulsiones/metabolismo , Índice de Severidad de la Enfermedad , Factores de Tiempo
10.
Exp Biol Med (Maywood) ; 231(6): 824-9, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16741006

RESUMEN

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin converting enzyme (ACE), neutral endopeptidase (NEP), and endothelin (ET) converting enzyme-1 (ECE-1), with respective IC(50) values of 22, 2, and 55 nM. The aim of the present study was to establish the hemodynamic profile of Zucker diabetic fatty (Zdf)-Fatty rats, a high-fat diet gene-prone model developing spontaneous Type 2 diabetes (T2D) and the effects of CGS 35601. Male Zdf-Fatty (14 weeks, n = 17-23), Zdf-Lean (14 weeks, n = 8-10), and Wistar (14 weeks, n = 9-10) rats on distinct diets were implanted with a catheter in the left carotid and placed individually in a metabolic cage for 30 days. The hemodynamic profile and some metabolic biomarkers were assessed daily. After a 7-day stabilization period, the Zdf-Fatty rats were divided into two groups: Group 1, controls (n = 7-10) receiving vehicle-saline (250 microl/hr) and Group 2, (n = 10-13) receiving increasing doses of CGS 35601 (0.1, 1, and 5 mg/kg/day x 6 days each, intra-arterially) followed by a 5-day washout period. Mean arterial blood pressure (MABP) of young Zdf-Fatty rats was compared with age-matched Zdf-Lean and Wistar rats, which were found similar. MABP decreased by 5.9% (from baseline at 102 +/- 5 to 96 +/- 4 mmHg), 12.7% (to 89 +/- 6 mmHg) and 21.6% (to 80 +/- 4 mmHg), at 0.1, 1, and 5 mg/kg/day, respectively, in CGS 35601-treated Zdf-Fatty rats. Systolic and diastolic blood pressures were similarly reduced. The heart rate was not affected. Hyperglycemic status and insulin-resistance were not modulated by short-term treatment. CGS 35601 presented an excellent short-term safety profile. This novel molecule and class of VPI may be of interest for lowering vascular tone. Further long-term studies, once cardiovascular and renal complications have developed in this T2D rat model are warranted to define the efficacy of this class of VPI.


Asunto(s)
Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/metabolismo , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Animales , Ácido Aspártico Endopeptidasas/administración & dosificación , Ácido Aspártico Endopeptidasas/farmacología , Combinación de Medicamentos , Enzimas Convertidoras de Endotelina , Indoles/administración & dosificación , Indoles/agonistas , Masculino , Metaloendopeptidasas/administración & dosificación , Metaloendopeptidasas/farmacología , Neprilisina/administración & dosificación , Neprilisina/farmacología , Peptidil-Dipeptidasa A/administración & dosificación , Peptidil-Dipeptidasa A/farmacología , Ratas , Ratas Wistar , Ratas Zucker
11.
Exp Biol Med (Maywood) ; 231(6): 830-3, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16741007

RESUMEN

We previously reported that CGS 35601, a potent triple inhibitor of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme 1, completely normalized mean arterial blood pressure (MABP) in 36-week-old spontaneously hypertensive rats, a normal renin model. The aim of the present study was to determine the effects of this triple vasopeptidase inhibitor (VPI) on the hemodynamic profile of instrumented, conscious, and unrestrained Dahl salt-sensitive (DSS) rats, a gene-prone, high-salt diet-induced low-renin hypertension model. Male DSS rats (mean weight [+/-SEM], 385 +/- 10 g) were fed a normal diet (Group 1) or a high-salt diet (Groups 2 and 3; 8% NaCl in food) for 6 weeks and then instrumented with a carotid catheter and placed individually in metabolic cages for 30 days. The hemodynamic, hematological, and biochemical profiles were assessed daily. Dose-dependent treatment started after a 7-day stabilization period in Groups 1 and 2 (vehicle dosage, 250 microl/hr) and Group 3 (CGS 35601 dosages of 0.1, 1, and 5 mg/kg/day for 6 days per dose by means of constant intra-arterial infusion), followed by a 5-day washout period. Two additional groups included normotensive Wistar rats (Group 4) and DSS rats that received a double high-salt solid (8% NaCl) and liquid (1% NaCl) diet (Group 5). The MABP in rats receiving CGS 35601 decreased in a dose-dependent fashion toward the baseline level observed in DSS rats receiving a normal diet. The heart rate was unaffected. The hemodynamic profile returned to normal during the washout period. This novel triple VPI is a potent and effective antihypertensive agent with a safe short-term profile that may be of interest for treating hypertension and other cardiovascular diseases. Other hypertensive rat models are being tested.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Renina/sangre , Sodio en la Dieta/farmacología , Animales , Ácido Aspártico Endopeptidasas/administración & dosificación , Ácido Aspártico Endopeptidasas/farmacología , Combinación de Medicamentos , Enzimas Convertidoras de Endotelina , Masculino , Metaloendopeptidasas/administración & dosificación , Metaloendopeptidasas/farmacología , Neprilisina/administración & dosificación , Neprilisina/farmacología , Peptidil-Dipeptidasa A/administración & dosificación , Peptidil-Dipeptidasa A/farmacología , Ratas , Ratas Endogámicas Dahl
12.
Drug Chem Toxicol ; 29(2): 183-202, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16707327

RESUMEN

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme-1 with respective IC50 values of 22, 2, and 55 nM. We characterized the safety profile and toxicity of escalating doses of CGS 35601 over a 20-day period in chronically instrumented, unrestrained, conscious, male, spontaneously hypertensive rats (SHR). Once instrumented with an arterial catheter, the SHR were placed in metabolic cages allowing daily assessment of hemodynamics and blood sampling for biochemical and hematological measurements. After a 7-day stabilization period, the SHR were divided into 2 groups: Gr. 1, (n = 13 to 18) receiving CGS 35601 at 0.01, 0.1, 1 and 5 mg kg(-1) day(-1) (continuous i.a. infusion) for 5 consecutive days/dose, followed by a 5-day washout; and Gr. 2, (n = 10) receiving vehicle (saline). The highest dose of CGS 35601 dose-dependently reduced MABP from 156 +/- 4 up to 94 +/- 5 mm Hg, whereas heart rate, metabolic, electrolytic, and hematological profiles, growth, diuresis, and renal activity were unaffected, and no hepatic or liver toxicities were observed. These results suggest that this novel triple VPI presents no safety concerns at this stage and may become of interest for the treatment of hypertension and other cardiovascular disorders. Long-term chronic experiments are needed to assess possible angioedema and increases in vascular permeability.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Evaluación Preclínica de Medicamentos , Hipertensión/tratamiento farmacológico , Indoles/farmacología , Metaloendopeptidasas/antagonistas & inhibidores , Neprilisina/antagonistas & inhibidores , Inhibidores de la Enzima Convertidora de Angiotensina/toxicidad , Animales , Presión Sanguínea/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Enzimas Convertidoras de Endotelina , Frecuencia Cardíaca/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Hipertensión/enzimología , Hipertensión/fisiopatología , Indoles/toxicidad , Masculino , Estructura Molecular , Ratas , Ratas Endogámicas SHR
13.
Vascul Pharmacol ; 43(4): 289-301, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16253569

RESUMEN

The aim of the present study was to assess several biochemical and physiological endpoint parameters alongside controlled hemorrhagic and recovery phases of chronically instrumented, conscious and unrestrained healthy rats. Male Sprague-Dawley rats (12-14 weeks; 430+/-20 g; n=22-18) were instrumented with a saline-perfused femoral arterial catheter and placed individually in a metabolic cage for up to 20 days, allowing instant assessments of the hemodynamic profile and blood and urine sampling for hematological profile and biochemical measurements to assess hepatic, renal and metabolic functions. In addition, body weight, food and water intake, and diuresis were monitored daily. After a 7-day stabilization period, the rats underwent severe and acute hemorrhagic shock (HS) (removal of 50% of total circulating blood volume), kept in hypovolemic shock for an ischemic period of 50 min and then resuscitated over 10 min. Gr. 1 was re-infused with autologous shed blood (AB; n=10) whereas Gr. 2 was infused 1:1 with a solution of sterile saline-albumin (SA; 7% w/v) (n=8-12). Ischemic rats recovered much more rapidly following AB re-infusion than those receiving SA. Normal hemodynamic and biochemical profiles were re-established after 24 h. Depressed blood pressure lasted 4-5 days in SA rats. The hematological profile in the SA resuscitated rats was even more drastically affected. Circulating plasma concentrations of hemoglobin (-40%), hematocrit (-50%), RBC (-40%) and platelets (-41%) counts were still severely decreased 24 h after the acute ischemic event whereas WBC counts increased 2.2-fold by day 4. It took 5-9 days for these profiles to normalize after ischemia-reperfusion with SA. Diuresis increased in both groups (by 45+/-7% on day 1) but presented distinct electrolytic profiles. Hepatic and renal functions were normal in AB rats whereas altered in SA rats. The present set of experiments enabled us to validate a model of HS in conscious rats and the use of an integrated in vivo platform as a valuable tool to characterize HS-induced stress and to test new classes of blood substitutes in real time, post-event, over days.


Asunto(s)
Sustitutos Sanguíneos/uso terapéutico , Hemodinámica/efectos de los fármacos , Choque/tratamiento farmacológico , Choque/fisiopatología , Enfermedad Aguda , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/fisiopatología , Animales , Biomarcadores , Proteínas Sanguíneas/análisis , Modelos Animales de Enfermedad , Electrólitos/sangre , Electrólitos/orina , Pruebas de Función Renal , Lípidos/sangre , Fallo Hepático Agudo/metabolismo , Fallo Hepático Agudo/fisiopatología , Pruebas de Función Hepática , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo , Daño por Reperfusión/fisiopatología , Choque/metabolismo , Telemetría
14.
Ann N Y Acad Sci ; 914: 387-93, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11085337

RESUMEN

The psychoactive indole alkaloid, ibogaine (IBO), has been investigated for over a decade concerning its reported anti-addictive properties for opioids as well as psychomotor stimulants. The mechanism for the anti-addictive action of IBO is still unclear. IBO interactions with opioid, NMDA, nicotinic, adrenergic, and serotonergic receptor sites have been suggested. The involvement of the dopaminergic system in IBO action is well documented. Increased or decreased levels of dopamine (DA) in specific brain regions following IBO pretreatment have been seen concomitantly with increased or decreased motor activity after subsequent amphetamine or cocaine administration. In this report, in vivo electrophysiological measures were monitored in awake adult male rats in order to investigate alterations of the electrocorticogram (ECoG) resulting from interactions between IBO and cocaine (COC). Rats were implanted bilaterally with bipolar ECoG electrodes. They were either injected with saline, COC alone (20 mg/kg, i.p.) or IBO (50 mg/kg, i.p.) and COC 1 hr later. The concentrations of DA, 5-HT, and their metabolites DOPAC, HVA, and 5-HIAA were assessed in the caudate nucleus in separate groups of saline-, COC-, and IBO/COC-treated rats. An alpha1 power increase was observed within 10 min after COC injection, which lasted for less than 20 min. A desynchronization over alpha2 and both beta power bands was observed throughout the recording. In IBO/COC-treated rats, a significant increase in delta, theta, and alpha1 power occurred within 20 min after COC injection (p <0.05). This effect lasted for up to an hour. DA levels significantly increased after COC only and decreased after IBO administration. A further decrease in levels of DA was observed in IBO/COC-treated rats. DA turnover increased significantly after IBO alone but was not observed after IBO/COC treatment. The alterations in ECoG and neurotransmitter levels suggest a decreased response to COC following IBO pretreatment.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Cocaína/farmacología , Inhibidores de Captación de Dopamina/farmacología , Electroencefalografía/métodos , Antagonistas de Aminoácidos Excitadores/farmacología , Ibogaína/farmacología , Ácido 3,4-Dihidroxifenilacético/metabolismo , Análisis de Varianza , Animales , Química Encefálica/efectos de los fármacos , Dopamina/metabolismo , Interacciones Farmacológicas , Ácido Homovanílico/metabolismo , Ácido Hidroxiindolacético/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Serotonina/metabolismo , Factores de Tiempo , Vigilia
15.
Psychol Rep ; 87(3 Pt 1): 729-30, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11191375

RESUMEN

The self-actualization scores of 57 youths who attended a summer day camp for gifted students were assessed using the Reflections Of Self by Youth (ROSY). Significant sex differences were confirmed. Contrary to Lewis's significant difference (1996) in mean self-actualization between Grades 7 and 8, self-actualization scores in this study were uncorrelated with grade.


Asunto(s)
Acampada/psicología , Individualismo , Psicología del Adolescente , Autoeficacia , Adolescente , Femenino , Identidad de Género , Humanos , Masculino , Inventario de Personalidad , Estaciones del Año
16.
Semin Perinatol ; 23(3): 250-60, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10405195

RESUMEN

Group B Streptococcus (GBS) is the most common cause of neonatal sepsis and meningitis. Despite antibiotics, GBS in the newborn initiates a cascade of molecular and biological events leading to altered cerebral perfusion, blood-brain barrier disruption, cerebral edema, intracranial hypertension, neurological damage, and even death. Having previously shown that GBS infection impairs cerebral blood flow autoregulation and increases prostaglandin (PG) levels, we examined the regulation of some crucial inflammatory mediators (PGs, nitric oxide (NO), tumor necrosis factor-a) in the brain and cerebral microvessels (MVs) from newborn piglets. Cyclooxygenase (COX), the key enzyme in PG biosynthesis, exists in two isoforms, COX-1 and COX-2. Both may be directly induced by NO in a model of renal inflammation. Besides its neurotransmitter role, NO is a potent vasorelaxant whose production is catalyzed by at least three distinct nitric oxide synthases (NOS) (bNOS, ecNOS, iNOS). Western blot analyses showed that the newborn (4 day old) brain expressed lower levels of COX-1 (8-fold), COX-2 (20-fold), bNOS (12-fold), and ecNOS (5-fold) than in the 1 day old. MV showed approximately equal levels of COX-2, lower levels of COX-1 (4-fold), bNOS (5-fold), and higher levels of ecNOS (20-fold) in comparison to 4-day-old cerebral MV. A 4-day-old brain expressed lower levels of bNOS (5-fold), ecNOS (10-fold), and COX-1 (2-fold) than the 6-week-old pig. COX-2 protein was undetected in a 4-day-old pig brain, but present in great excess in MV. Purified MV showed lower ecNOS (14-fold), COX-1 (2-fold), and about equal levels of bNOS and COX-2 in comparison with MV from 6-week-old pigs. Reverse transcription polymerase chain reaction analyses confirmed these results. Treatment with noo-nitro-L-arginine (LNA), a NOS inhibitor, downregulated COX-1 expression in the newborn brain and both COX-1 and COX-2 cerebral MV expression. GBS infection (10(9) colony-forming units, 0.5 mL intracerebroventricular) of sedated newborn piglets induced the expression of tumor necrosis factor-alpha in the cerebrospinal fluid after 2 hours, upregulated bNOS expression in both brain and MVs, upregulated ecNOS in MVs, and downregulated COX-1, COX-2, and ecNOS in the brain. GBS did not trigger the expression of iNOS. Our data suggest that there is a net deficiency of NOS isoforms in the immature brain and microvasculature of the 4-day-old piglet and that the differences in expression lead to the immature control of NO and PG production, rendering newborns particularly susceptible to neurological damage because of the undeveloped nature of their response mechanisms. Moreover, the GBS-induced cascade deregulates the gene expression of interacting inflammatory mediators and may cause a net vasoconstrictor/vasodilator imbalance, leading to cerebral hypertension and edema in the early stages of infection. Pharmacological manipulations of the inflammatory cascade could lead to novel therapeutic approaches for the treatment of GBS meningitis.


Asunto(s)
Encéfalo/enzimología , Regulación de la Expresión Génica , Meningitis Bacterianas/enzimología , Microcirculación/enzimología , Óxido Nítrico Sintasa/genética , Prostaglandina-Endoperóxido Sintasas/genética , Animales , Encéfalo/irrigación sanguínea , Encefalopatías/etiología , Humanos , Recién Nacido , Inflamación/enzimología , Inflamación/microbiología , Meningitis Bacterianas/complicaciones , Infecciones Estreptocócicas/enzimología , Streptococcus agalactiae
17.
Ann N Y Acad Sci ; 844: 265-73, 1998 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-9668684

RESUMEN

Ibogaine (IBO) is a psychoactive indole alkaloid that has antiaddictive properties. However, treatment with IBO may lead to neurotoxicity, since IBO and its metabolites interact persistently with many neurotransmitter systems. Here, we recorded cortical electroencephalogram (EEG) signals from rats anesthetized with isoflurane. The heart rate (HR) was monitored via electrocardiogram (EKG) electrodes. After the baseline EEG was recorded, rats received one intraperitoneal (i.p.) dose of 50 mg/kg IBO. EEG signals were recorded for 2 hr. Rats were then sacrificed and brains dissected into frontal cortex (FC), caudate nucleus (CN), hippocampus (HIP), and brain stem (BS). The level of dopamine (DA), serotonin (5-HT), and their metabolites were determined by high-performance liquid chromatography with electrochemical detection (HPLC-ECD). Compared with baseline, a decrease in HR immediately after IBO injection and a decrease in delta, theta, alpha and beta power spectra frequency bands (1-4, 4-8, 8-13, 13-32 Hz) during the first 30 min after IBO administration was observed. EEG recovered within the next 15 min. In CN, the level of DA decreased and DA turnover rate increased significantly. The levels of 5-HT increased in FC. The pattern of EKG AND EEG response to IBO may be due to multiple receptor interactions of IBO.


Asunto(s)
Monoaminas Biogénicas/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Electroencefalografía , Ibogaína/farmacología , Animales , Encéfalo/fisiología , Dopamina/metabolismo , Frecuencia Cardíaca/efectos de los fármacos , Inyecciones Intraperitoneales , Masculino , Concentración Osmolar , Ratas , Ratas Sprague-Dawley , Distribución Tisular
18.
J Vasc Surg ; 25(4): 611-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9129615

RESUMEN

PURPOSE: The purpose of this study was to validate the commonly accepted indicators of risk of ischemic stroke that indicate the necessity for cerebral protection during carotid endarterectomy (CEA), and to examine the efficacy of high-dose thiopentone sodium (thiopental) as a cerebral protection method in patients who are at high risk of intraoperative ischemic stroke. METHOD: In a prospective study of 37 CEAs performed for symptomatic stenosis > 70%, functional and clinical indicators of risk of ischemic stroke during carotid cross-clamping were identified. Functional indicators of risk were the development of ischemic electro-encephalogram (EEG) changes and stump pressure < 25 mm Hg. Clinical indicators of risk were previous ischemic hemispheric stroke and severe bilateral disease. These indicators were correlated in all patients, some of whom had two or three coexisting indicators of risk. The EEG and stump pressure were monitored continuously during carotid occlusion in all operations. Carotid occlusion times were recorded. Intraluminal shunting was eliminated in favor of high-dose thiopental cerebral protection in all patients. Neurologic outcome was deemed to measure the efficacy of thiopental protection in patients who are identified to be at risk and, hence, in need of cerebral protection. The validity of the indicators used to identify risk of ischemic stroke during CEA was assessed. RESULTS: The absolute stroke risk was found to be 29.7% for the whole group (37 patients) and 57.9% in 19 patients who had commonly accepted indications for protective shunting. The correlation of ischemic EEG changes with stump pressure < 25 mm Hg was only 27.3%, whereas the expected correlation based on well-documented reports in the literature was 100%. The lack of correlation may have been related to the prevention of ischemic EEG changes by thiopental. There were no neurologic deficits in the series. CONCLUSIONS: The absence of neurologic deficit in the study indicated that thiopental protection was effective in preventing ischemic stroke in high-risk patients and safely replaced intraluminal shunting.


Asunto(s)
Isquemia Encefálica/etiología , Trastornos Cerebrovasculares/etiología , Endarterectomía Carotidea/efectos adversos , Complicaciones Intraoperatorias/prevención & control , Fármacos Neuroprotectores/uso terapéutico , Medición de Riesgo , Tiopental/uso terapéutico , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Isquemia Encefálica/prevención & control , Arterias Carótidas/patología , Estenosis Carotídea/patología , Estenosis Carotídea/cirugía , Circulación Cerebrovascular/efectos de los fármacos , Trastornos Cerebrovasculares/prevención & control , Constricción , Electroencefalografía , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio , Examen Neurológico , Fármacos Neuroprotectores/administración & dosificación , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de Riesgo , Tiopental/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento
19.
Int J Occup Environ Health ; 3(1): 5-12, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9891095

RESUMEN

An epidemiologic study was carried out in order to evaluate the effects of prevention programs at the workplace aimed at reducing back, neck, and shoulder morbidity among active workers. The intervention group included 275 workers in three occupational subgroups: hospital workers, warehouse workers, and office workers. The control group included 250 workers as comparable as possible to the intervention group. Comparisons were made, according to one-year changes in morbidity scores, for low back, upper back, neck, and shoulder disorders separately. An overall measure was also used. The one-year change in the overall measure was significantly different between the intervention group and the control group, indicating a positive effect of the prevention programs. Positive effects were stronger for some sites of pain and some occupational groups.

20.
J Trauma ; 40(1): 123-5, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8576975

RESUMEN

Posttraumatic pseudoaneurysms of the hepatic artery are rare and usually occur as a complication of open abdominal trauma. Even less common is the coexisting presence of enteric fistulization. We report a patient with upper gastrointestinal hemorrhage occurring 3 years after blunt abdominal trauma resulting from a pseudoaneurysm of the proper hepatic artery with duodenal fistulization. The patient was treated successfully by ligation of the proper hepatic artery and closure of the duodenal opening.


Asunto(s)
Traumatismos Abdominales/complicaciones , Aneurisma Falso/etiología , Enfermedades Duodenales/etiología , Arteria Hepática/lesiones , Fístula Intestinal/etiología , Heridas no Penetrantes/complicaciones , Adulto , Aneurisma Falso/diagnóstico por imagen , Enfermedades Duodenales/diagnóstico por imagen , Hemorragia Gastrointestinal/etiología , Humanos , Fístula Intestinal/diagnóstico por imagen , Masculino , Radiografía , Factores de Tiempo
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