RESUMO
CD40 promotes survival, proliferation, and differentiation of normal B cells but can cause activation-induced cell death in malignant B lymphocytes. CD40 ligand and anti-CD40 antibodies have been used successfully to induce apoptosis in lymphoma lines both in vitro and in xenograft tumor models. Although this makes CD40 an attractive target for antitumor therapies, the response of malignant B cells to CD40 signaling is variable, and CD40 stimulation can enhance proliferation and can increase chemoresistance in some cell lines. It would therefore be useful to identify markers that predict whether a specific cell line or tumor will undergo apoptosis when stimulated with CD40 and to identify targets downstream of CD40 that affect only the apoptotic arm of CD40 signaling. We have analyzed gene expression patterns in CD40-sensitive and CD40-resistant diffuse large B-cell lymphoma (DLBCL) cell lines to identify signaling pathways that are involved in CD40-mediated apoptosis. CD40-resistant lines expressed pre-B-cell markers, including RAG and VPREB, whereas CD40-sensitive cells resembled mature B cells and expressed higher levels of transcripts encoding several members of the CD40 signaling pathway, including LCK and VAV. In addition, CD40-sensitive DLBCL cell lines also displayed constitutive activation of extracellular signal-regulated kinase (ERK) and failed to undergo apoptosis when ERK phosphorylation was inhibited. In contrast, CD40-resistant lines showed no constitutive activation of ERK and no increase in ERK activity in response to CD40 stimulation. Our results suggest that constitutive activation of ERK may be required for death signaling by CD40.
Assuntos
Apoptose/fisiologia , Antígenos CD40/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Linfoma de Células B/enzimologia , Linfoma de Células B/patologia , Linfoma não Hodgkin/patologia , Linhagem Celular Tumoral , Ativação Enzimática , Perfilação da Expressão Gênica , Humanos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Linfoma de Células B/imunologia , Linfoma não Hodgkin/enzimologia , Linfoma não Hodgkin/imunologia , Sistema de Sinalização das MAP Quinases , Fosforilação , Proteínas Proto-Oncogênicas c-vav/metabolismoRESUMO
BACKGROUND: Since the very early documentation of medical treatments, bathing is an essential part of almost all traditional medical systems. In this context the oil-dispersion bath, developed in the 1930s by Werner Junge has been developed from anthroposophic medicine. We aimed at analyzing the apparatus, which churns water and essential oils into an oil-water dispersion, by means of an experimental study. MATERIAL AND METHODS: Using three different oils (rheumatic oil, citrus oil and rosemary oil) oil volumetric flow rate and oil droplet size distribution were examined at three different water volumetric flow rates of 5, 10, and 15 l/min at a constant temperature of 40 °C. Additionally, for the rheumatic oil measurements are taken at three different temperatures, 35, 40, and 45 °C at a constant volumetric flow rate of 10 l/min. Finally results were compared with a manual oil dispersion process. RESULTS: Oil volumetric flow rate increases with increasing water volumetric flow rates. Oil flow rate increases with increasing water temperature. Droplet-size distribution shows an optimal fit with a log-normal distribution for a volumetric flow rate of 5 l/min in all oils applied with citrus and rosemary oil showing a larger mean diameter compared to the rheumatic oil. Comparing the oil droplet size distribution for a traditional oil bath, distributions behaved completely different in comparison to our distributions. Moreover it seemed not possible to create an oil-dispersion with repeatable droplet size distributions whereas the Jungebad apparatus created similar oil dispersions with predictable results, independent of the user. DISCUSSION: This is the first study to explore the mechanisms of creation of the oil-dispersion bath by means of an experimental set up. Based on these experimental results, a more fundamental theoretical approach should be carried out to complement our findings and to gain deeper insights in the hydrodynamic and droplets forming processes in the Jungebad apparatus.
Assuntos
Banhos , Óleos Voláteis/química , Água , Citrus/química , Difusão , Humanos , Lipídeos , Rosmarinus/químicaRESUMO
BACKGROUND AND PURPOSE: Late infantile neuronal ceroid lipofuscinosis (CLN2 disease) is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene. Our hypothesis was that regional analysis of cortical brain degeneration may identify brain regions that are affected earliest and most severely by the disease. MATERIALS AND METHODS: Fifty-two high-resolution 3T MR imaging datasets were prospectively acquired on 38 subjects with CLN2. A retrospective cohort of 52 disease-free children served as a control population. The FreeSurfer software suite was used for calculation of cortical thickness. RESULTS: An increased rate of global cortical thinning in CLN2 versus control subjects was the primary finding in this study. Three distinct patterns were observed across brain regions. In the first, subjects with CLN2 exhibited differing rates of cortical thinning versus age. This was true in 22 and 26 of 34 regions in the left and right hemispheres, respectively, and was also clearly discernable when considering brain lobes as a whole and Brodmann regions. The second pattern exhibited a difference in thickness from healthy controls but with no discernable change with age (9 left hemispheres, 5 right hemispheres). In the third pattern, there was no difference in either the rate of cortical thinning or the mean cortical thickness between groups (3 left hemispheres, 3 right hemispheres). CONCLUSIONS: This study demonstrates that CLN2 causes differential rates of degeneration across the brain. Anatomic and functional regions that degenerate sooner and more severely than others compared with those in healthy controls may offer targets for directed therapies. The information gained may also provide neurobiologic insights regarding the mechanisms underlying disease progression.
Assuntos
Encéfalo/patologia , Degeneração Neural/patologia , Lipofuscinoses Ceroides Neuronais/patologia , Criança , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tripeptidil-Peptidase 1RESUMO
Development of strategies for prevention of breast cancer development requires an understanding of the effects of mammary oncogenes on mammary cells at early stages in neoplastic transformation. As mammary oncogenes wnt-1 and int-2 affect different signal transduction pathways, we investigated their effects on established mouse mammary epithelial cell lines (MMECLs) reflecting early stages in tumorigenesis. Normal interactions between beta-catenin and E-cadherin were abrogated in all three immortalized MMECLs and the cells lacked beta-catenin-mediated transactivation activity, detectable using a reporter assay, suggesting that alterations in cell adhesion may be very early events in mammary tumorigenesis. Immortalized FSK4 and EL12 cells and hyperplastic TM3 cells were stably transfected with expression vectors encoding wnt-1 or int-2 or the control vector, and drug-selected pooled cells from each line were confirmed by reverse transcription-polymerase chain reaction to express the transfected oncogene; this expression persisted in the cells analysed in vitro and in vivo. Resultant phenotypic changes depended both on the oncogene and the target mammary cell line. In FSK4 cells, expression of wnt-1 or int-2 resulted in proliferative changes in vitro, including reduced contact inhibition, increased beta-catenin expression, and decreased p53 transcriptional activity, but neither oncogene conferred upon those cells the ability to produce tumors in vivo. EL12 cells were highly refractory to the effects of both oncogenes, with the only measurable changes being increased E-cadherin levels induced by both oncogenes and increased proliferation of the int-2-transfected cells in the absence of serum. Parental TM3 cells were phenotypically similar to wnt-1- or int-2-transfected FSK4 cells and displayed an increased rate of proliferation in vitro and markedly increased tumorigenicity in vivo following transfection with int-2 but not with wnt-1. These results suggest that wnt-1 signaling is redundant in the hyperplastic TM3 cells and indicate that wnt-1-induced effects in the immortalized FSK4 and EL12 cells were not sufficient to mediate a tumorigenic phenotype. This study showed that the wnt-1 and int-2 oncogenes have similar but distinguishable effects on immortalized MMECLs and that the genetic background of the mammary cells greatly influences the consequences of oncogene expression at early stages of cell transformation.
Assuntos
Proteínas do Citoesqueleto/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Transativadores , Proteínas de Peixe-Zebra , Animais , Caderinas/metabolismo , Adesão Celular , Divisão Celular , Linhagem Celular , Meios de Cultura Livres de Soro , Células Epiteliais/citologia , Feminino , Fator 3 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/genética , Expressão Gênica , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Transcrição Gênica , Ativação Transcricional , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt , Proteína Wnt1 , beta CateninaRESUMO
RT6 is an enzymatically active GPI-anchored membrane protein that was originally discovered in the rat as a peripheral T cell alloantigen. It has attracted interest as an activation antigen and because defective RT6-expression coincides with increased susceptibility for autoimmune type I diabetes in the BB rat. Southern blot analyses indicate that the rat carries a single copy RT6 gene whereas the mouse carries a duplication of the homologous locus. We had previously cloned and sequenced a RT6-homologous cDNA from BALB/c mouse spleen. We now report the cloning and characterization of a second RT6-homologue from BALB/c and 129/Sv mice. The two mouse Rt6 genes (designated Rt6-1 and Rt6-2) encode similar open reading frames that are disrupted by conserved introns. The nucleotide sequences of the Rt6-1 and Rt6-2 coding regions show 87% sequence identity, the deduced amino acid sequences 79% identity. The amino acid sequences reveal significant similarity to recently cloned ADP-ribosylating ectoenzymes from rabbit and human skeletal muscle as well as chicken bone marrow cells. RT-PCR analyses reveal that the two Rt6 genes are differentially expressed in distinct inbred mouse strains and that their transcripts are properly processed. Western blot analyses demonstrate that the respective gene products are released from cells by treatment with PI-PLC. The results further show that both mouse Rt6 genes are translated into GPI-anchored cell surface molecules and that Rt6 gene expression is restricted to peripheral lymphoid tissues.
Assuntos
Antígenos de Diferenciação de Linfócitos T/química , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/genética , Poli(ADP-Ribose) Polimerases/química , Poli(ADP-Ribose) Polimerases/genética , Sequência de Aminoácidos , Animais , Antígenos de Diferenciação de Linfócitos T/isolamento & purificação , Sequência de Bases , Southern Blotting , Clonagem Molecular , Reações Cruzadas , Antígenos de Histocompatibilidade/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Família Multigênica/imunologia , Fosfatidilinositol Diacilglicerol-Liase , Fosfoinositídeo Fosfolipase C , Diester Fosfórico Hidrolases/farmacologia , Poli(ADP-Ribose) Polimerases/isolamento & purificação , Reação em Cadeia da Polimerase , Homologia de Sequência de Aminoácidos , Baço/imunologia , Transcrição Gênica/imunologiaRESUMO
The effects of cold storage and type of preservation solution on coronary endothelial function are not well understood. Experiments were designed to evaluate coronary endothelial-dependent relaxation after a 4-hr cold (4 degrees C) storage in different preservation solutions. Isolated rat hearts were studied in the Langendorff apparatus for coronary endothelial function. After 30 min of stabilization, hearts were arrested with a 10-min perfusion of 4 degrees C crystalloid hyperkalemic cardioplegic solution (CHCS) containing 24 mmol/L of KCl and stored for 4 hr in the following preservation solutions: CHCS, Krebs-Ringer's solution (KR), 0.9% NaCl (NS), and University of Wisconsin solution (UW). A fifth group was perfused and stored in UW solution. Endothelial-dependent and independent coronary artery vasorelaxation were tested, respectively, by infusing 5-hydroxytryptamine (5-HT) (1 x 10(-6) mol/L) and sodium nitroprusside (SNP) (1 x 10(-5) mol/L) before and 30 min after the storage period. In hearts stored in CHCS and KR, the coronary artery flow increase to 5-HT and SNP infusion were not significantly affected. However, in hearts preserved with NS and UW solutions, 5-HT coronary response was significantly decreased, indicating endothelial dysfunction. In addition to these findings, coronary flow increase to SNP infusion was decreased in the group perfused and stored with UW, suggesting smooth muscle damage. These experiments suggest that 4-hr cold storage in NS or UW impairs endothelial-dependent coronary relaxation in the isolated rat heart model.
Assuntos
Soluções Cardioplégicas , Endotélio Vascular/patologia , Coração , Soluções para Preservação de Órgãos , Preservação de Órgãos/métodos , Adenosina , Alopurinol , Animais , Circulação Coronária/efeitos dos fármacos , Glutationa , Insulina , Soluções Isotônicas , Masculino , Nitroprussiato/farmacologia , Compostos de Potássio , Rafinose , Ratos , Ratos Sprague-Dawley , Serotonina/farmacologia , Vasodilatação/efeitos dos fármacosRESUMO
T. annulata, the causative agent of tropical theileriosis in cattle, can also infect ovine and caprine leukocytes in vitro. In vivo studies showed that this parasite causes a mild infection in both these animal species, and in sheep merozoite stage development seems to be inhibited. Since the nature of T. annulata infected caprine and ovine cells is not known, all three cell lines were karyotyped and phenotypically characterized by flow cytometry. They all express mRNA of cytokines IL-1 alpha, IL-1 beta, IL-8, and TNF-alpha, but not of IFN-gamma, IL-2, and IL-4. In contrast, IL-6 mRNA was expressed in the cattle cell line only, while mRNA of IL-10 was exclusively produced by the sheep cell line. The observed differences in cytokine mRNA expression may be responsible for the different pathogenesis of T. annulata infection in cattle and sheep.
Assuntos
Citocinas/genética , Linfócitos/imunologia , Linfócitos/parasitologia , Theileria annulata/imunologia , Animais , Bovinos , Células Cultivadas , Regulação da Expressão Gênica/imunologia , Cabras , Interleucinas/genética , Ativação Linfocitária , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos , Transcrição GênicaRESUMO
BACKGROUND: Calcium-channel blockers have been reported to improve myocardial recovery after ischemia-reperfusion, but their effects on coronary blood flow regulation remain to be defined. Experiments were designed to evaluate the effects of calcium antagonists on coronary artery vasoregulation exposed to ischemia-reperfusion. METHODS: Three groups of hearts (n = 6) were pretreated with a 10-minute infusion of either diltiazem, verapamil, or nifedipine at concentrations of 10(-9) mol/L to 10(-6) mol/L and exposed to 30 minutes of no-flow ischemia and 45 minutes of reperfusion. Another group (n = 6) received no pretreatment and was used as control. Endothelium-dependent and -independent relaxations were tested by assessing coronary flow increase to 5-hydroxytryptamine (10(-6) mol/L) and sodium nitroprusside (10(-5) mol/L) infusion, respectively. Left ventricular pressure, its first derivative, and coronary basal flow were recorded before and after ischemia as well as during calcium antagonist infusion. RESULTS: Endothelium-dependent relaxation after ischemia was significantly improved with all three drugs in a dose-dependent fashion; nifedipine was found to be the more potent. Endothelium-independent relaxation was also significantly preserved with calcium antagonists regardless of the type, whereas left ventricular hemodynamics were not. During perfusion, nifedipine was found to have the most negative inotropic effect and to be the most potent vasodilator on the coronary circulation. Diltiazem was the less effective drug on both left ventricular hemodynamics and coronary circulation. CONCLUSIONS: This study indicates that preischemic infusion of calcium antagonists enhance endothelium-dependent and -independent coronary artery relaxation in the isolated rat heart model in a dose- and drug-dependent fashion. This can be achieved at low doses without affecting left ventricular hemodynamics and should contribute to preserve coronary artery autoregulation.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Vasos Coronários/efeitos dos fármacos , Diltiazem/farmacologia , Endotélio Vascular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Nifedipino/farmacologia , Verapamil/farmacologia , Animais , Circulação Coronária/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Infusions of crystalloid hyperkalemic cardioplegic solutions (CHCSs) are known to impair endothelium-dependent coronary relaxation. This impairment might also be influenced by high perfusion pressure and duration of CHCS infusion. To verify this hypothesis, we designed experiments to study the influence of pressure and duration of CHCS infusion as modulating factors in CHCS-related endothelial impairment. Isolated hearts of Sprague-Dawley rats were studied in a Langendorff apparatus for coronary endothelial function. Hearts (n = 6) were exposed to four different CHCSs containing 12, 24, 40, or 100 mmol/L of potassium chloride (KCl). Endothelial and smooth muscle functions were respectively tested by infusion of 5-hydroxytryptamine (1 x 10(-6) mol/L) and sodium nitroprusside (1 x 10(-5) mol/L) before and after CHCS perfusion. In group I (n = 24), 37 degrees C CHCSs were perfused at 80 cm H2O of pressure for 30 minutes. In group II (n = 24), the same CHCSs were perfused at 160 cm H2O for 30 minutes. In group III (n = 18), CHCSs containing 24, 40, and 100 mmol/L of KCl were infused at 160 cm H2O for 10 minutes. In all groups, response to sodium nitroprusside was unaltered by CHCS infusion, indicating that smooth muscle function was preserved. However, in group II, 5-hydroxytryptamine-induced vasodilation was significantly impaired in hearts perfused with CHCS containing 24 mmol/L of KCl or more, suggesting endothelial damage. This study demonstrates that, in addition to KCl concentration, pressure and duration of infusion are two major determinants in CHCS-mediated endothelial damage.
Assuntos
Vasos Coronários/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Compostos de Potássio , Potássio/administração & dosagem , Animais , Circulação Coronária/efeitos dos fármacos , Vasos Coronários/fisiologia , Endotélio Vascular/fisiopatologia , Técnicas In Vitro , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Nitroprussiato/farmacologia , Pressão , Ratos , Ratos Sprague-Dawley , Serotonina/farmacologia , Fatores de Tempo , Vasodilatação/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacosRESUMO
Chronic exposure to cyclosporine affects vascular reactivity. Experiments were designed to characterize the endothelium-dependent and endothelium-independent vascular reactivity of rats exposed to oral cyclosporin A (CyA). Two subsets of rats (n = 6) were treated with CyA (20 mg/kg/day) and olive oil (cyclosporine vehicle), respectively, for a period of 8 weeks. Aortic rings (4-5 mm) were suspended for isometric force measurement in organ chambers containing Krebs Ringer solution (37 degrees C, 95% O2, 5% CO2). The maximal endothelium-dependent relaxation to cumulative doses of acetylcholine was significantly decreased in the CyA-treated aortic rings compared to olive oil-treated ones (data expressed as percent of initial contraction; CyA, 50% +/- 3% versus olive oil, 37% +/- 7%; p < 0.05). However, endothelium-dependent relaxations to histamine and adenosine diphosphate and endothelium-independent relaxation to sodium nitroprusside were not affected in both groups. An endothelium-dependent contraction to serotonin and aggregating platelets were observed in the CyA group, but not in the control group. The endothelium-independent contraction to norepinephrine was enhanced in the CyA group (CyA ED50, log -7.66 +/- 0.18 mol/L versus olive oil ED50, log -7.01 +/- 0.11 mol/L; p < 0.01). These experiments suggest that chronic exposure to cyclosporine A could contribute to augmenting vascular tone by (1) decreased release of endothelial relaxing factor mediated by muscarinic receptors, (2) increased production of endothelium-related constricting factor mediated by serotoninergic receptors, and (3) greater vascular smooth muscle sensitivity to circulating catecholamine.
Assuntos
Aorta/efeitos dos fármacos , Ciclosporina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Óleos de Plantas/farmacologia , Acetilcolina/farmacologia , Difosfato de Adenosina/farmacologia , Administração Oral , Animais , Aorta/patologia , Aorta/fisiopatologia , Colesterol/sangue , Relação Dose-Resposta a Droga , Portadores de Fármacos , Endotélio Vascular/fisiopatologia , Histamina/farmacologia , Soluções Isotônicas , Lipoproteínas LDL/sangue , Lipoproteínas LDL/efeitos dos fármacos , Masculino , Músculo Liso Vascular/fisiopatologia , Óxido Nítrico , Nitroprussiato/farmacologia , Azeite de Oliva , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Serotonina/farmacologia , Fatores de TempoRESUMO
University of Wisconsin (UW) solution has been reported to enhance myocardial preservation in heart transplantation. To evaluate the effects of UW solution on coronary artery endothelial function, we designed experiments to compare UW solution with a standard crystalloid hyperkalemic cardioplegic solution (CHCS). Isolated rat hearts were studied in a modified Langendorff apparatus for coronary endothelial function. Groups 1 and 2 were perfused with 4 degrees C CHCS (24 mmol/L of KCl) and UW solution, respectively, for 10 minutes at a pressure of 80 cm H2O, whereas group 3 underwent warm ischemia for 10 minutes. Groups 4 and 5 were perfused with and stored for 4 hours in cold (4 degrees C) CHCS and UW solution, respectively. Group 6 underwent 4 hours of topical cooling (4 degrees C) without any cardioplegic perfusion. All groups had 6 hearts each. Endothelium-dependent relaxation and endothelium-independent relaxation of the coronary arteries were tested by infusing 5-hydroxytryptamine (5HT) (10(-6) mol/L) and sodium nitroprusside (10(-5) mol/L), respectively, before and after perfusion with and storage in one of the two cardioplegic solutions. The coronary vasodilatation induced by 5HT and sodium nitroprusside was not altered in hearts perfused with (group 1) or perfused with and stored in CHCS (group 4). Coronary flow increase after 5HT infusion was significantly decreased in hearts perfused with (group 2) (before, 35% +/- 10%; after, 13% +/- 10%; p < 0.01) or perfused with and stored in UW solution (group 5) (before, 34% +/- 5%; after, -5% +/- 12%), indicating severe endothelial dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Soluções Cardioplégicas/farmacologia , Circulação Coronária/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Soluções para Preservação de Órgãos , Soluções/farmacologia , Vasodilatação/efeitos dos fármacos , Adenosina , Alopurinol , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Circulação Coronária/fisiologia , Endotélio Vascular/fisiologia , Glutationa , Insulina , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Óxido Nítrico/fisiologia , Preservação de Órgãos , Perfusão , Rafinose , Ratos , Ratos Sprague-Dawley , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologia , Vasodilatação/fisiologia , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologiaRESUMO
OBJECTIVE: To evaluate the effects of the calcium channel blocker diltiazem and its chloride derivative clentiazem on coronary vasoregulation of isolated rat hearts exposed to ischemia-reperfusion. Diltiazem has been reported to prevent postreperfusion myocardial damage but its beneficial effects on coronary blood-flow regulation remain uncertain. METHODS: Two groups of hearts were pretreated with a 10 min infusion of either diltiazem (10(-9) to 10(-6) mol/L) or clentiazem (10(-9) to 10(-7) mol/L) (n = 6 for each concentration) and exposed to 30 mins of no-flow ischemia. Another group (n = 6) received no pretreatment and was used as control. Endothelium-dependent and -independent relaxation were tested by assessing coronary flow increase to 5-hydroxytriptamine (10(-6) mol/L) and sodium nitroprusside (10(-5) mol/L) infusions, respectively, and were assessed before and after ischemia-reperfusion. Left ventricular pressure, dP/dt and coronary basal flow were also recorded. Postreperfusion results are expressed as a percentage of pre-ischemic value. Dunnet variance analysis was used to compare means of pretreated groups with the control group. RESULTS: Endothelium-dependent relaxation was significantly improved with both drugs. Optimal preservation was obtained with diltiazem 10(-6) mol/L (66 +/- 4%) and clentiazem 10(-7) mol/L (83 +/- 4%), whereas endothelial response was almost abolished in control hearts (6 +/- 11%, P < 0.01). Clentiazem was found to be more potent than diltiazem at low concentration (10(-9) mol/L, clentiazem 89 +/- 13% versus diltiazem 3 +/- 16%, P < 0.05). Optimal endothelium-independent relaxation preservation was achieved at 10(-8) mol/L in both groups (diltiazem 86 +/- 4%, clentiazem 82 +/- 8%, control 47 +/- 10%, P < 0.05). Left ventricular pressure and dP/dt were not affected by any pretreatment. However, postreperfusion coronary basal flow was significantly increased in control hearts. CONCLUSION: This study indicated that pre-ischemic infusion of diltiazem and clentiazem enhances endothelium-dependent and -independent coronary artery relaxation following reperfusion in the isolated rat heart model, without affective ventricular hemodynamics, and contributes to preservation of coronary artery autoregulation.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Diltiazem/análogos & derivados , Diltiazem/farmacologia , Isquemia Miocárdica/tratamento farmacológico , Animais , Bloqueadores dos Canais de Cálcio/administração & dosagem , Circulação Coronária/efeitos dos fármacos , Diltiazem/administração & dosagem , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Endotélio/efeitos dos fármacos , Masculino , Reperfusão Miocárdica , Óxido Nítrico/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
Addition of magnesium to a preservation solution such as St Thomas's Hospital solution has been shown to improve myocardial preservation. High concentration of magnesium can affect coronary artery endothelial-dependent relaxation. Isolated rat hearts were studied in the Langendorff apparatus to investigate whether magnesium-enriched hyperkalemic cardioplegic solution (HCS) could alter coronary endothelial function. Hearts in group 1 (n = 8) were perfused for 30 mins with a standard hyperkalemic cardioplegic solution (potassium chloride 24 mmol/L). Hearts in group 2 (n = 8) were perfused with modified St Thomas' Hospital solution (MST) containing 16 mmol/L of magnesium chloride and 24 mmol of potassium chloride. The endothelium dependent and endothelium independent relaxation of the coronary arteries were respectively assessed by infusing 5-hydroxytryptamine (5-HT) (1 x 10(-6) mol/L) and sodium nitroprusside (SNP) (1 x 10(-5) mol/L) before and after perfusion of cardioplegic solutions. Hearts in group 2 showed a reduction of the 5-HT-induced coronary flow increase following the MST exposure (before, 8.66 +/- 0.86 mL/min; after, 5.66 +/- 0.97 mL/min, P < 0.01) whereas hearts in group 1 were not significantly affected (before, 8.00 +/- 0.68 mL/min; after, 6.99 +/- 1.02 mL/min, not significant), suggesting endothelial dysfunction in the former. Coronary flow response to SNP was not affected in either group.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Soluções Cardioplégicas/farmacologia , Vasos Coronários/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Cloreto de Magnésio/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Animais , Bicarbonatos/farmacologia , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Cloreto de Cálcio/farmacologia , Vasos Coronários/fisiologia , Vasos Coronários/cirurgia , Endotélio Vascular/fisiologia , Técnicas In Vitro , Magnésio/farmacologia , Masculino , Relaxamento Muscular/fisiologia , Reperfusão Miocárdica , Nitroprussiato/farmacologia , Ratos , Ratos Sprague-Dawley , Serotonina/farmacologia , Cloreto de Sódio/farmacologia , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologiaRESUMO
We have screened different mouse strains-including strains with enhanced susceptibility for autoimmune diseases-for deviations of Rt6 gene expression by RT-PCR. Most strains expressed varying amounts of Rt6-1 and Rt6-2. NZW mice, however, do not show any detectable Rt6-2 gene transcripts. BxSB mice show a near complete absence of Rt6-1 gene transcripts. Southern blot and sequence analyses revealed that NZW mice have suffered a deletion of the Rt6.2 gene while the Rt6-1 gene of BxSB mice has been inactivated by a premature stop codon. Thus, these mouse strains represent natural Rt6-2 and Rt6-1 single-gene 'knock-out's, respectively. Since the NZW mouse does not show any gross immunological abnormalities, loss of the Rt6-2 gene by itself is not associated with any obvious immunological phenotype. However, crosses between NZW and certain other mouse strains, e.g. (NZW x NWB)F1 and (NZW x SB)F1 animals, develop a systemic autoimmune disease reminiscent of human lupus erythematosus. Moreover, the BxSB mouse strain is considered to be an independent model for the same disease. It will be of interest to determine whether these spontaneous Rt6 gene defects constitute part of the polygenetic contribution to autoimmune disease in these animals.
Assuntos
ADP Ribose Transferases , Antígenos de Histocompatibilidade/genética , Glicoproteínas de Membrana , Camundongos Knockout/genética , Poli(ADP-Ribose) Polimerases/genética , Animais , Antígenos de Diferenciação de Linfócitos T , Southern Blotting , Proteínas Ligadas por GPI , CamundongosRESUMO
The structure of the RT6 mono(ADP-ribosyl)transferase gene was studied. Analysis of cDNA clones revealed eight exons and suggested two independent transcriptional start sites. The existence of the downstream initiation site was confirmed by S1-nuclease protection and localized to position +29 of exon 2. The corresponding 5' flanking regions were found to contain typical promoter structures such as TATA- and CCAAT-boxes. Comparison with sequences deposited in the TRANSFAC database of transcription factor binding sites revealed few putative regulatory elements in the region associated with exon 1 (promoter 1). In contrast, several elements contained in the regulatory regions of other T cell-specific genes, such as ets, lyf-1 and ikaros were found in in promoter 2. Analysis of RT6-transcripts showed this region to be the most active promoter in spleen cells of adult rats. Finally, transient transfection assays with reporter gene constructs showed promoter 2 to mediate T-cell specific transcription.
Assuntos
ADP Ribose Transferases/genética , Antígenos de Diferenciação de Linfócitos T/genética , Regulação da Expressão Gênica , Glicoproteínas de Membrana/genética , Regiões Promotoras Genéticas , Animais , Iniciação Traducional da Cadeia Peptídica , Ratos , Transcrição Gênica , Células Tumorais CultivadasRESUMO
STUDY OBJECTIVE: To compare sevoflurane-nitrous oxide with propofol-nitrous oxide for the induction and maintenance of anesthesia, and to determine the rates of recovery following each anesthetic. DESIGN: Randomized, controlled study. SETTING: Teaching hospital. PATIENTS: 50 ASA physical status I and II patients, ranging in age from 18 to 70 years. INTERVENTIONS: General anesthesia was induced with either sevoflurane or propofol and maintained with 60% to 70% nitrous oxide and either sevoflurane or a propofol infusion and supplemental fentanyl. At the conclusion of surgery, the oxygen flow was increased to 6 L/min and all anesthetics were discontinued simultaneously. Patients were monitored for the nature and speed of induction and emergency from anesthesia. MEASUREMENTS AND MAIN RESULTS: Induction of anesthesia was significantly slower in the sevoflurane group than in the propofol group (2.0 +/- 1.1 vs. 0.8 +/- 0.5 min, respectively). The ease of induction and the time required for emergence from anesthesia were the same in both study groups (eye opening: 9.0 +/- 4.4 min vs. 8.0 +/- 5.0 min; following commands: 11.2 +/- 5.0 min vs. 9.8 +/- 6.9 min; extubation: 9.1 +/- 4.5 min vs. 8.6 vs. 5.1 min in the sevoflurane and propofol groups, respectively). Patients in the sevoflurane group experienced nausea and vomiting more frequently than patients in the propofol group (13 and 5 patients vs. 3 and 0 patients in the sevoflurane and propofol groups, respectively), which were not related to the administration of neostigmine or intraoperative opioids. CONCLUSION: Sevoflurane allows for rapid inhalation induction of, and emergence from, general anesthesia.
Assuntos
Anestesia Geral , Anestésicos Inalatórios/administração & dosagem , Anestésicos Intravenosos/administração & dosagem , Éteres/administração & dosagem , Éteres Metílicos , Óxido Nitroso/administração & dosagem , Propofol/administração & dosagem , Adolescente , Adulto , Idoso , Período de Recuperação da Anestesia , Anestesia por Inalação , Anestesia Intravenosa , Anestésicos Inalatórios/efeitos adversos , Éteres/efeitos adversos , Feminino , Fentanila/administração & dosagem , Humanos , Intubação Intratraqueal , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Náusea/induzido quimicamente , Óxido Nitroso/efeitos adversos , Oxigênio/administração & dosagem , Sevoflurano , Fatores de Tempo , Vômito/induzido quimicamente , VigíliaRESUMO
The title compound, C(16)H(26)O(2), (I), prepared by oxidation of (1R*,11R*)-12-hydroxybicyclo[9.4.1]hexadecan-16-one using pyridinium dichromate, has a trans configuration of the two fused rings and represents an interesting precursor for the synthesis of macrocyclic structures.
RESUMO
Cyclosporine A (CyA) affects vascular reactivity but its effect on local vascular tone following endothelial regeneration is unknown. Experiments were designed to study the effects of CyA on endothelial and smooth muscle reactivity of endothelium-regenerated arteries. Three groups of rats (n = 8) were subjected to aortic mechanical denudation. Subsequently a first group was treated 8 weeks with CyA (20 mg/kg) and a second one with an equivalent volume of CyA vehicle: olive oil (OL). A last group was submitted to a standard diet and represented the control group (CTL). After 8 weeks, aortic rings were suspended in organ chambers for assessment of endothelial and smooth muscle function. Maximal endothelial dependent relaxation to acetylcholine (CyA: 52 +/- 3%, OL: 50 +/- 4%, CTL: 48 +/- 5%; p = NS), adenosine diphosphate (CyA: 30 +/- 7%, OL: 18 +/- 2%, CTL: 24 +/- 5%; p = NS) and histamine (CyA: 38 +/- 6%, OL: 43 +/- 4%, CTL: 47 +/- 5%; p = NS) were comparable among all groups. In aortic segments studies without endothelium, increased contraction to serotonine was significantly lessened in the OL group (CyA: 259 +/- 43%, OL: 153 +/- 11%, CTL: 243 +/- 24%; p < 0.05). Maximal tension to cumulative doses of norepinephrine was increased in rings without endothelium treated with CyA (CyA: 5.8 +/- 0.6 g, OL: 4.2 +/- 0.5 g, CTL: 4.0 +/- 0.2 g; p < 0.05). All these differences were abolished in rings studied with endothelium. Endothelial independent relaxation to sodium nitroprusside were similar among all groups. In conclusion, CyA does not specifically affect endothelium-dependent relaxation of the regenerated aortic endothelium. However, our model suggests that CyA increases vascular tone mediated by increased smooth muscle sensitivity to norepinephrine and serotonine but these effects are prevented by the regenerated endothelium. This experiment demonstrates the ability of the regenerated endothelium to prevent CyA-induced vascular toxicity.
Assuntos
Aorta Torácica/efeitos dos fármacos , Ciclosporina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Imunossupressores/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Animais , Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Norepinefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Vasoconstritores/farmacologiaRESUMO
The effects of cold storage and type of preservation solution on coronary endothelial function are not well established. Experiments were designed to evaluate coronary endothelial-dependent relaxation after a 4-hour cold (4 degrees C) storage in different preservation solutions. Rat hearts, mounted in the Langendorff apparatus, were arrested with a 10-minute perfusion of 4 degrees C crystalloid hyperkaliemic cardioplegic solution (CHCS) (KCl 24 mEq/l) and stored for 4 hours in the following preservation solutions: CHCS (n = 6), Krebs-Ringer solution (KR) (n = 6), 0.9% NaCl (NS) (n = 6) and the University of Wisconsin solution (UW) (n = 6). A fifth group (n = 6) was perfused and stored in UW solution. Endothelium-dependent and independent coronary artery vasorelaxations were respectively tested by infusing 5-hydroxytryptamine (5-HT) (10(-6) mol/l) and sodium nitroprusside (SNP) (10(-5) mol/l) before and after the storage period. In hearts stored with CHCS or KR, coronary artery flow increase to 5-HT and SNP infusions were not significantly affected. However, in hearts preserved with NS or UW solutions, 5-HT coronary response was significantly decreased, indicating endothelial dysfunction. In addition to these findings, coronary flow increase to SNP infusion was decreased in the group perfused and stored with UW, suggesting smooth muscle dysfunction. These experiments suggest that 4-hour cold storage in NS or UW impairs endothelial-dependent coronary relaxation in the isolated rat heart model.
Assuntos
Endotélio Vascular/efeitos dos fármacos , Soluções Isotônicas/farmacologia , Soluções para Preservação de Órgãos , Compostos de Potássio/farmacologia , Preservação de Tecido/métodos , Adenosina/farmacologia , Alopurinol/farmacologia , Animais , Vasos Coronários/efeitos dos fármacos , Glutationa/farmacologia , Transplante de Coração/métodos , Insulina/farmacologia , Masculino , Rafinose/farmacologia , Ratos , Ratos Sprague-Dawley , Solução Salina Hipertônica/farmacologia , Vasodilatação/efeitos dos fármacosRESUMO
122 parents and 18 teachers rated Head Start children on the preschool version of the Behavioral Assessment System for Children. Parents tended to rate their children as having greater problem scores than did their teacher, but both ratings, when compared to general norms, were within normal limits. Low to moderate correlations were found for the same scales on Parent and Teacher forms. Teachers rated children in the center program as having fewer problems than their home-based peers, while parents evaluated center children as having better adaptive behavior than children in the home-based program. Boys had more clinical problems than girls, while girls were rated as showing more adaptive behavior than boys. The usefulness and need for further research on this assessment are mentioned.