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251.
Souza Vdo C Schlemmer KB Noal CB Jaques JA Bagatini MD Pimentel VC Carli LF Leal CA Fleck J Moretto MB Schetinger MR Leal DB 《Purinergic signalling》2012,8(4):753-762
Chagas disease (CD) is a chronic and endemic illness caused by the parasite Trypanosoma cruzi. Microvascular disturbances play an important role in the progress of the disease. The purinergic signaling system participates in regulatory functions, such as immunomodulation, neuroprotection, and thromboregulation. This study aimed to investigate the activities of purinergic system ecto-enzymes present on the platelet surface and the platelet aggregation profile from patients with indeterminate form of Chagas disease (IFCD). Thirty patients diagnosed with IFCD and 30 healthy subjects were selected. Ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP), ecto-5′-nucleotidase (E-5′-NT) and ecto-adenosine deaminase (E-ADA) activities were measured in platelets isolated from these individuals as well as the platelet aggregation. Results demonstrated an increase of 21 % in the E-NPP activity and 30 % in the E-5′-NT activity in IFCD group (P < 0.05); however, a decrease of 34 % in the E-ADA activity was determined in the same group (P < 0.001). A significant decrease of 12.7 % and 12.8 % in the platelet aggregation of IFCD group in two different concentrations of ADP (5 and 10 μM) was observed, respectively (P < 0.05). Increased E-NPP and E-5-NT activities as well as decreased E-ADA activity in platelets of patients with IFCD contributed to decrease platelet aggregation, suggesting that the purinergic system is involved in the thromboregulation process in these patients, since adenosine (the final product of ATP hydrolysis) has cardioprotective and vasodilator effects that prevent the clinical progress of the disease. 相似文献
252.
Titanium is known to possess excellent biocompatibility as a result of corrosion resistance, lack of allergenicity when compared with many other metals. Fluoride is well known as a specific and effective caries prophylactic agent and its systemic application has been recommended widely over recent decades. Nevertheless, high fluoride concentrations impair the corrosion resistance of titanium. The purpose of this article is to summarize the current data regarding the influence of fluoride on titanium corrosion process in the last 5?years. These data demonstrate noxious effects induced by high fluoride concentration as well as low pH in the oral cavity. Therefore, such conditions should be considered when prophylactic actions are administrated in patients containing titanium implants or other dental devices. 相似文献
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Sj?gren-Larsson syndrome (SLS) is an inherited neurocutaneous disorder characterized by ichthyosis, mental retardation, spasticity, and deficient activity of fatty aldehyde dehydrogenase (FALDH). FALDH is an enzyme component of fatty alcohol:NAD oxidoreductase (FAO), which is necessary for fatty alcohol metabolism. To better understand the biochemical basis for the cutaneous symptoms in this disease, we investigated lipid metabolism in cultured keratinocytes from SLS patients. Enzyme activities of FALDH and FAO in SLS cells were <10% of normal. SLS keratinocytes accumulated 45-fold more fatty alcohol (hexadecanol, octadecanol, and octadecenol) than normal, whereas wax esters and 1-O-alkyl-2,3-diacylglycerols were increased by 5.6-fold and 7.5-fold, respectively. SLS keratinocytes showed a reduced incorporation of radioactive octadecanol into fatty acid (24% of normal) and triglyceride (13% of normal), but incorporation into wax esters and 1-O-alkyl-2,3-diacylglycerol was increased by 2.5-fold and 2.8-fold, respectively. Our results indicate that FALDH deficiency in SLS keratinocytes causes the accumulation and diversion of fatty alcohol into alternative biosynthetic pathways. The striking lipid abnormalities in cultured SLS keratinocytes are distinct from those seen in fibroblasts and may be related to the stratum corneum dysfunction and ichthyosis in SLS. 相似文献
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Costa NJ Bombardieri CR Kuribayashi JS de Camargo MM Andrade LH Kagohara E Espósito BP 《化学与生物多样性》2008,5(10):2156-2159
It is shown that metal complexes of the biodegradable ligand ethylenediaminedisuccinic acid (edds) present antimicrobial activity towards fungi and bacteria. [Cd(edds)], in particular, is more toxic than free Cd2+ to Aspergillus niger, behaving as a 'Trojan Horse' in the facilitated delivery of the toxic metal into the fungus. 相似文献
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Kaw Bing Chua Kenny Voon Gary Crameri Hui Siu Tan Juliana Rosli Jennifer A. McEachern Sivagami Suluraju Meng Yu Lin-Fa Wang 《PloS one》2008,3(11)
First discovered in the early 1950s, reoviruses (respiratory enteric orphan viruses) were not associated with any known disease, and hence named orphan viruses. Recently, our group reported the isolation of the Melaka virus from a patient with acute respiratory disease and provided data suggesting that this new orthoreovirus is capable of human-to-human transmission and is probably of bat origin. Here we report yet another Melaka-like reovirus (named Kampar virus) isolated from the throat swab of a 54 year old male patient in Kampar, Perak, Malaysia who was suffering from high fever, acute respiratory disease and vomiting at the time of virus isolation. Serological studies indicated that Kampar virus was transmitted from the index case to at least one other individual and caused respiratory disease in the contact case. Sequence analysis of the four small class genome segments indicated that Kampar and Melaka viruses are closely related. This was confirmed by virus neutralization assay, showing an effective two-way cross neutralization, i.e., the serum against one virus was able to neutralize the other. Although the exact origin of Kampar virus is unknown, epidemiological tracing revealed that the house of the index case is surrounded by fruit trees frequently visited by fruit bats. There is a high probability that Kampar virus originated from bats and was transmitted to humans via bat droppings or contaminated fruits. The discovery of Kampar virus highlights the increasing trend of emergence of bat zoonotic viruses and the need to expand our understanding of bats as a source of many unknown viruses. 相似文献
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