RESUMEN
The referral of critically ill cancer patients to an intensive care unit (ICU) is a matter of controversial debate. This study was conducted by an interdisciplinary clinical group to evaluate the outcome of ICU treatment in cancer patients according to their characteristics at the time of referral. A retrospective analysis was used to identify relevant subgroups among 189 consecutive cancer patients referred as emergencies to one of four ICUs during a 2-year period. Reasons for ICU referral were pneumonia (29.6%), sepsis (27.0%), fungal infection (11.1%), another infection (9.5%), gastrointestinal emergency (16.9%), treatment-related organ toxicity (6.9%), or other, non-infectious complications (43.9%). Vasopressor support was required in 50.3%, mechanical ventilation in 49.7%, and haemodialysis/-filtration in 26.5% of the patients. Overall, 41.3% died during ICU treatment, 12.2% died after transfer from ICU to a non-ICU ward, and 35.4% were discharged alive. Sepsis, mechanical ventilation, vasopressor support, renal replacement therapy and neutropenia were independent risk factors for fatal outcome, but no single risk factor unequivocally predicted death. All patients with fungal infection who required vasopressor support and either had sepsis (n=13) or needed mechanical ventilation (n=14) died during ICU treatment, while all non-septic patients. who did not require mechanical ventilation, were younger than 74 years of age and had a non-infectious underlying complication (n=29), survived. This analysis may help to early identify relevant subgroups of cancer patients with different prognoses under ICU treatment. A prospective study to confirm the predictive usefulness of this approach is needed. Cancer patients should not be excluded from referral to the intensive care unit in an emergency solely due to their underlying malignant disease or a single unfavourable prognostic factor.
Asunto(s)
Cuidados Críticos , Neoplasias/terapia , Derivación y Consulta/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crítica , Árboles de Decisión , Urgencias Médicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Micosis/terapia , Neutropenia/terapia , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos , Factores de Riesgo , Sepsis/terapia , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
Restenosis after initially successful balloon angioplasty of coronary artery stenosis remains a major problem in clinical cardiology. Previous studies have identified pathogenetic factors which trigger cell proliferation and vascular remodeling ultimately leading to restenosis. Since there is evidence that endothelial cells adjacent to the angioplasty wound area synthesize factors which may initiate this process, we investigated the effects of mechanical stimulation on endothelial gene expression in vitro and focussed on the influence of sustained mechanical stress on expression of immediate early genes which have previously been shown to be induced in the vascular wall in vivo. Primary cultured human umbilical vein endothelial cells (HUVEC) and the human endothelial cell line EA.hy 926 were plated on collagen-coated silicone membranes and subjected to constant longitudinal stress of approximately 20% for 10 min to 6 h. Total RNA was isolated and the expression of the immediate early genes c-Fos and Egr-1 was studied by Northern blot analysis. We found a rapid upregulation c-Fos and Egr-1 mRNA which started at 10 min and reached its maxima at 30 min. HUVEC lost most of their stretch response after the third passage whereas immediate early gene expression was constantly in EA.hy 926 cells. Using specific inhibitors we investigated the contribution of several signal transduction pathways to stretch-activated Egr-1 mRNA expression. We found significant suppression of stretch-induced Egr-1 mRNA expression by protein kinase C (PKC) inhibition (p < 0.05) and by calcium depletion (EA.hy 926, p < 0.05; HUVEC, p = 0.063). No effect on stretch-activated Egr-1 mRNA expression was detected by inhibition of protein kinase A, blockade of stretch-activated cation channels or inhibition of microtubule synthesis. We conclude that sustained mechanical strain induces Egr-1 mRNA expression by PKC- and calcium-dependent mechanisms.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Endotelio Vascular/metabolismo , Proteínas Inmediatas-Precoces/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Transducción de Señal , Sulfonamidas , Factores de Transcripción/metabolismo , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Actinas/metabolismo , Northern Blotting , Línea Celular , Células Cultivadas , Quelantes/farmacología , Colchicina/farmacología , Proteínas de Unión al ADN/genética , Proteína 1 de la Respuesta de Crecimiento Precoz , Ácido Egtácico/farmacología , Endotelio Vascular/citología , Inhibidores Enzimáticos/farmacología , Gadolinio/farmacología , Humanos , Proteínas Inmediatas-Precoces/genética , Isoquinolinas/farmacología , Microscopía Fluorescente , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas c-fos/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Estrés Mecánico , Factores de Transcripción/genética , Venas UmbilicalesRESUMEN
It has been suggested that the renin-angiotensin system (RAS) interacts with the endothelin system in the pathogenesis of cardiac remodeling. We examined endothelin system regulation in a model of chronic RAS dysfunction, which is believed to be an important factor in cardiac remodeling. We used the transgenic rat line TGR(mRen2)27, which overexpresses the mouse Renin-2 gene and shows hypertension and left ventricular hypertrophy compared to Sprague-Dawley (SD) rats. Ren-2 rats (n = 24) received either losartan (LOS), quniapril (QIN), or carvedilol (CARV) for 11 weeks, or no treatment. After 11 weeks left (LV) and right ventricular (RV) weights were determined and total RNA extracted. Ren-2 rats showed a mean systolic blood pressure of 190 mm (+/- SEM), which could be normalized to 110 +/- mm (+/- SEM) by treatment with LOS or QIN. CARV also reduced blood pressure but did not normalize it. LV end-diastolic pressure was normal in both SD and Ren-2 rats. LV weight was increased in the Ren-2 rats compared to SD rats, and was significantly reduced to normal in the LOS and QIN but not in the CARV group. RV weight was normal in all groups. Northern blot analysis of preproendothelin-1 (preproET-1) and endothelin-converting enzyme-1 (ECE-1) expression revealed a significant (p < 0.05) 20% decrease in preproET-1 mRNA in the mRen2 rats in the RV and in the LV, compared to SD rats. ECE-1 mRNA was unchanged. Treatment with LOS, but not with QIN or CARV, induced preproET-1 transcription by threefold (p < 0.01) over baseline in both the LV and RV. ECE-1 mRNA was unaltered in the CARV and LOS group and was decreased by 20% in the QIN group. Similar changes in LV and RV indicated a direct influence of a dysregulated RAS on the endothelin system. In conclusion, the activated RAS downregulates the endothelin system in this model of cardiac hypertrophy. This suggests that in chronic RAS activated, the endothelin system may have a different pathophysiologic impact as a co-factor leading to cardiac hypertrophy.
Asunto(s)
Cardiomegalia/fisiopatología , Endotelinas/fisiología , Sistema Renina-Angiotensina/fisiología , Renina/biosíntesis , Animales , Animales Modificados Genéticamente , Ácido Aspártico Endopeptidasas/biosíntesis , Ácido Aspártico Endopeptidasas/genética , Presión Sanguínea/fisiología , Northern Blotting , Cardiomegalia/genética , Enzimas Convertidoras de Endotelina , Endotelinas/biosíntesis , Endotelinas/genética , Masculino , Metaloendopeptidasas , Ratones , ARN Mensajero/biosíntesis , Ratas , Ratas Endogámicas , Ratas Sprague-Dawley , Renina/genética , Sistema Renina-Angiotensina/genéticaRESUMEN
OBJECTIVE: Replication-deficient, recombinant adenovirus is used as a carrier for gene transfer, but it is unspecific and the onset of transgene expression is relatively late. Here, we evaluated the efficiency and selectivity of gene transfer mediated by recombinant Semliki Forest virus (SFV). METHODS: We compared the efficiency of a SFV-based vector with an adenoviral vector, using LacZ as a reporter gene. Firstly, the affinity for vascular smooth muscle cells, endothelial cells and cardiac myocytes was assessed. Secondly, we compared the time course of LacZ expression and cytotoxicity in vascular smooth muscle cells. RESULTS: The SFV-based vector infects vascular smooth muscle cells and cardiomyocytes as efficiently as adenovirus. In contrast to adenovirus, SFV hardly transfers LacZ to endothelial cells (2.6% or less). SFV-mediated expression was visible after 1 h, reaching a maximum after 6 h. In contrast, adenovirus-mediated expression became visible after 6 h, and reached a maximum after 48-72 h. Both vectors were cytotoxic. CONCLUSIONS: We demonstrate that SFV efficiently transfers LacZ to vascular smooth muscle cells and cardiomyocytes, but not to endothelial cells. In contrast, adenovirus causes efficient transgene expression in all cell types tested. Furthermore, SFV-mediated expression is faster than adenovirus-mediated expression. Therefore, SFV-mediated gene transfer may be a suitable alternative to adenovirus, providing a fast expression in non-endothelial cardiovascular cell types.
Asunto(s)
Adenoviridae , Técnicas de Transferencia de Gen , Vectores Genéticos , Miocardio/citología , Virus de los Bosques Semliki , Animales , Supervivencia Celular , Células Cultivadas , Endotelio Vascular/citología , Expresión Génica , Operón Lac , Músculo Liso Vascular/citología , RatasRESUMEN
The brain has abundant nuclear T3-binding sites and contains messenger RNAs (mRNAs) encoding multiple thyroid hormone receptor (TR) isoforms; the cellular distribution of these different TR isoforms is unknown. To determine whether the TR isoforms are differentially expressed in neuronal and astroglial cells, we examined the relative abundance of the mRNAs encoding TR alpha 1, c-erbA alpha 2, and TR beta 1 in primary cultures of fetal rat brain and in several cell lines of neural and glial origin. Additionally, the TR isoform polypeptides were identified by immunocytochemistry using isoform-specific antibodies. Northern blot analysis showed that fetal brain cell cultures contain mRNAs encoding the T3-binding isoforms TR alpha 1 and TR beta 1 as well as the mRNA encoding the non-T3-binding c-erbA alpha 2. c-erbA alpha 2 mRNA was most abundant, comprising more than 85% of the TR mRNAs in the primary cultures. Neuronal enrichment by antimitotic selection increased TR beta 1 mRNA approximately 3-fold, decreased c-erbA alpha 2 mRNA 70%, and had little or no effect on TR alpha 1 mRNA. Neuronal depletion resulted in the complete loss of TR beta 1 mRNA without changing c-erb alpha 2 or TR alpha 1 mRNA levels. Primary cultures of rat astrocytes, the astrocytoma cell line C6, and the pheochromocytoma cell line PC12 contained only the c-erbA alpha 2 mRNA. Immunocytochemistry using isoform-specific anti-sera revealed that TR beta 1 was exclusively localized to neuronal nuclei, and c-erbA alpha 2 was only found in the nuclei of astrocytes. These results show that TR beta 1 is localized to the nuclei of neuronal cells, and that c-erbA alpha 2 is restricted to the nuclei of astrocytes.
Asunto(s)
Astrocitos/metabolismo , Expresión Génica , Neuronas/metabolismo , Receptores de Hormona Tiroidea/genética , Animales , Northern Blotting , Encéfalo/citología , Encéfalo/efectos de los fármacos , Encéfalo/embriología , Células Cultivadas , Citarabina/farmacología , Femenino , Técnica del Anticuerpo Fluorescente , Células PC12 , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Hormona Tiroidea/análisisRESUMEN
The effect of the antidepressant desipramine (DMI) on the activities of the three iodothyronine deiodinase isoenzymes involved in the central metabolism of thyroid hormones were investigated in 11 brain regions and 3 peripheral tissues in the rat. The investigations were carried out at three different times during the light/dark cycle: 5 A.M., 1 P.M. and 11 P.M. Interest is focused on changes in the two enzymes that catalyze: i) the 5'deiodination of T4 to the biologically active T3, i.e., type II 5'deiodinase (5'D-II), and ii) the 5 (or inner-ring) deiodination of T3 to the biologically inactive 3,3'T2, i.e., type III 5 deiodinase (5D-III). Fourteen days' treatment with 20 mg/kg DMI, but not with 5 mg/kg DMI, induced significant increases in 5'D-II in eight different areas of the CNS. The regions affected were identical to those that receive noradrenergic input from the locus coeruleus. Even control animals showed a circadian rhythm of 5'D-II activity in some brain regions, and the effects of DMI also depended on the time of death within the 24-hr rhythm. 5D-III was not affected. Serum T4 were lower after administration of DMI, most probably because of enhanced tissue uptake of T4. This is in line with the corresponding finding in depressed patients, indicating that similar changes in both central and peripheral thyroid hormone metabolism may occur after antidepressant pharmacotherapy in both humans and rats. These data support the hypothesis that interactions with the CNS metabolism of the thyroid hormones may be involved in the mechanisms of action of DMI.