197,376 research outputs found
Cardiovascular effects of Tacca integrifolia Ker-Gawl. extract in rats
No full textRhizome of Tacca integrifolia, a Thai folk medicinal herb, has been used for controlling blood pressure and improving sexual function in humans. However, the biological activities of this herb on the cardiovascular system have not yet been documented. In the present study, we investigated the cardiovascular effects of methanolic extract from the rhizome of this herb (Tacca extract). In the in vivo study, intravenous injection of the Tacca extract (0.04-40 mg/kg) caused a decrease in both mean arterial blood pressure and heart rate of anesthetized rats (Nembutal sodium, 60 mg/kg, i.p.) in a dose dependent manner. Pretreatment of the animals with muscarinic receptor antagonist, atropine (1 mg/kg, i.v.), significantly reduced the hypotensive and the negative chronotropic activities of the Tacca extract. In the in vitro preparation, the Tacca extract (0.001-3 mg/ml) caused a decrease in both force and rate of spontaneous contraction of isolated atria in a dose dependent manner. These effects were reduced by preincubation of the atria with atropine (10-7 or 10-6 M). For isolated blood vessels, the Tacca extract (0.003-3 mg/ ml) caused vasodilation of endothelium-intact thoracic aortic rings pre-constricted with phenylephrine (3× 10-6 M). This effect disappeared after pre-incubation of blood vessels with atropine (10-6 M) or with Nω-nitro- L-arginine (3×10-4 M), or by removing the vascular endothelium. The results obtained suggest that the hypotensive and negative chronotropic effects of the Tacca extract in the rat are due to the active components acting via the muscarinic receptors at the blood vessel to cause vasodilatation by stimulating the release of nitric oxide, as well as on the muscarinic receptors at the atria to cause the decrease of both rate and force of the atrial contraction
Land Registration Practices and Rural Administrative Reforms. Hamlets and Commons in the 18th century Savoy|PRATICHE DI CATASTAZIONE E RIFORME DELLA MAGLIA AMMINISTRATIVA RURALE: BORGATE E BENI COMUNI NELLA SAVOIA DEL DICIOTTESIMO SECOLO
No full textStarting from the observation of one of the first modern land register in Europe, the Perequazione Generale della Savoia, the article deals with some questions regarding property, common resources exploitation and the relationship between common resources and the administrative structure of territory. The article compares cadastral maps and registers with documents regarding juridical conflicts for common resources exploitation in the second half of XVIII century. This comparison will shed light on two different territorial and administrative models: on one hand the arrangement created by the Perequazione, that aims to a progressive centralization of local political unities and their resources; on the other hand the model exposed by social actors during conflicts, focused on a great number of family-based settlement units that claim the ownership of common resources
The effects of the somatostatin analog octreotide on angiogenesis in vitro
No full textThis study examined the in vitro antiangiogenic effects of the somatostatin analog octreotide on the growth of human HUV-EC-C endothelial cells and vascular cells from explants of rat aorta cultured on fibronectin-coated dishes or included in fibrin gel. A total 10(-9) mol/L octreotide reduced the mean uptake of 3H-thymidine by HUV-EC-C cells by 37% compared with controls. The 10(-8) mol/L concentration of octreotide inhibited the proliferation of endothelial and smooth muscle cells growing on fibronectin by 32.6% and reduced the sprouting of cells from the adventitia of aortic rings in fibrin by 33.2% compared with controls, as measured by tetrazolium bioreduction and image analysis, respectively. These results demonstrate that octreotide is an effective inhibitor of vascular cell proliferation in vitro
Teratogenesis and immunosuppressive treatment
No full textDespite the potential risks to the mother and fetus caused by immunosuppressive drugs, uneventful pregnancies are now frequent among transplant recipients. Although there is no apparent increase in the type or incidence of malformations in the newborns or evidence of graft dysfunction, pregnancy-related complications, including premature termination and low birth weight, may be more frequent. To prevent graft rejection due to the increased immunologic reactivity of the transplant recipient during pregnancy, it is reasonable to wait 2 years after transplantation before conception, to have stable graft function and to be on low drug doses for maintenance immunosuppression. Among the immunosuppressive agents, corticosteroids may induce a number of treatment-related complications, including diabetes and osteoporosis; however, the incidence of fetal malformations during corticosteroid treatment is about 3.5%, a value close to that of the general population. Among immunosuppressive antibodies, no evidence of developmental toxicity has been demonstrated with basiliximab. On the contrary, some concerns have been raised about azathioprine, since its use has been associated with fetal abnormalities in animals; however, clinical data so far have indicated only a small teratogenic risk. Therefore, immunosuppressive therapy with selected drugs and antibodies does not apparently increase the risk of birth defects and may be continued in pregnancy. Finally, although breast-feeding is not recommended, because of drug transfer into maternal milk, the available clinical data do not support this limitation because of the low amount of drug absorbed by the infant and the absence of clinical toxicity in published case reports
Hematologic toxicity of immunosuppressive treatment
No full textThe administration of immunosuppressive agents may be associated with the occurrence of hematologic toxicity, such as anemia, due to bone marrow suppression or hemolysis, leukopenia, and thrombocytopenia. The administration of azathioprine and mycophenolate mofetil is more frequently associated with bone marrow suppression, while hemolytic-uremic syndrome may occur after administration of cyclosporine, tacrolimus, or muromonab (OKT3) and may be associated with the loss of the allograft. Moreover, microangiopathic hemolytic anemia and thrombocytopenia are rare, but potentially severe, complications of immunosuppressive treatment with tacrolimus and cyclosporine; they are characterized by intravascular hemolysis due to mechanical destruction of red cells as a result of pathological changes in small blood vessels. Viral infections (cytomegalovirus), administration of antiviral agents (gancyclovir), inhibitors of angiotensin-converting enzyme and angiotensin II receptor antagonists, antibacterial agents (sulfamethoxazole and trimethoprim), and allopurinol may aggravate bone marrow suppression, particularly when administered with agents that interfere with purine biosynthesis, including azathioprine and mycophenolate mofetil
Fructose-1,6-diphosphate reduces acute ECG changes due to doxorubicin in isolated rat heart
No full textDoxorubicin (DXR) (0.17 x 10(-4) M) induces an acute cardiotoxicity in isolated rat heart; there is a progressive widening of the S alpha T segment, with a decrease in force derivatives and in the coronary flow. Concurrent perfusion with fructose-1,6-diphosphate (FDP) (10(-5)-10(-4) M) dose-dependently reduces the S alpha T enlargement but fails to affect the reduction in force derivatives and coronary flow. The target of cardiac protection by FDP might be the ionic mechanisms underlying the action potential configuration
The effect of osteogenic growth peptide (OGP) on proliferation and adhesion of HEMC-1 human endothelial cells
No full textHuman osteogenic growth peptide (OGP) promotes the growth of osteoblastic, fibroblastic and bone marrow stromal cells. There is no evidence that OGP stimulates the growth or the attachment of endothelial cells to the extracellular matrix. The aim of this study was to test OGP on in vitro cultures of human microvascular endothelial HEMC-1 cells and to characterize its potential angiogenic effect when administered alone or in combination with vascular endothelial growth factor (VEGF) or its binding protein alpha(2)-macroglobulin (alpha(2)M). HEMC-1 cells were cultured in vitro under serum-free conditions to study the effects of OGP (10(-14)- 10(-10)M), VEGF (100 ng ml(-1)), alpha(2)M (20 ng ml(-1)) and their combinations on cell proliferation for 48 h. Furthermore, an adhesion assay was performed incubating the HEMC-1 cells with OGP, VEGF, alpha(2)M and their combinations for 24 h. OGP, alpha(2)M and their combination did not stimulate proliferation of HEMC-1 cells; in contrast, VEGF caused a significant enhancement of cell growth ( +37.3 %;P< 0.05). Pre-incubation with VEGF resulted in a fast and increased adhesion of endothelial cells to the matrix as compared to controls ( +87.5 % at 30 min and +86.6 % at 70 min, P< 0.05); in contrast, incubation with OGP alone determined only a significant increase in the attachment at 100 min ( +52 %;P< 0.05). The combinations of these peptides did not cause significant additive effects. These results suggest that OGP, compared to VEGF, induced neither the proliferation nor an increase in attachment of HEMC-1 cells to a matrix, either alone or in combination with VEGF and alpha(2)M. These in vitro findings may suggest a possible administration of OGP, as a haematopoietic factor, to patients affected by pathological conditions involving angiogenesis
- …
