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281.
Background: Coronary artery disease as a consequence of atherosclerosis is the most common cause of morbidity and mortality in type 2 Diabetes Mellitus (DM) patients. Homocysteine (HCY), as one of the risk factors, and uric acid (UA) as the most common antioxidant in serum have their roles in the processes of inflammation and atherogenesis, which underlie the pathogenesis of acute myocardial infarction (AMI). The effect of HCY in cardiovascular disease is thought to be manifested primarily through oxidative damage, implying a potential correlation between the HCY level and antioxidant status. Since the data related to the diagnostic significance of both HCY and UA in diabetic patients with AMI are conflicting, and so far not reported in Bosnian patients, this research aimed to examine the association of HCY and UA levels with glomerular filtration rate (eGFR) and explore the pathophysiological significance of these data in Bosnian diabetic patients with AMI. Methods: This prospective research included 52 DM type 2 patients diagnosed with AMI. Blood samples were taken on admission and used for biochemical analysis. Results of the biochemical analyses were statistically analysed. Results: Elevated HCY and UA levels were observed in diabetic patients. Females have higher HCY compared to males. A positive correlation was revealed between HCY and UA and was confirmed with different HCY levels in subgroups with different UA level. A negative correlation was observed between UA and HbA1c, as well as between both HCY and UA with eGFR. Conclusions: These results contribute to the clarification of the biochemical mechanisms characteristic in AMI patients with DM. According to these results, we believe that joint measurement of HCY and UA could enable a better assessment of the prognosis for this group of patients. This kind of assessment, as well as regression analysis, can identify high-risk patients at an earlier stage when appropriate interventions can influence a better outcome in such patients.  相似文献   
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The role of histidine residues in pectinesterases was evaluated by monitoring the sensitivity to modification with diethyl pyrocarbonate in the tomato andAspergillus niger enzymes. Different and incomplete losses of enzyme activity were obtained. Inactivation of the enzymes was proportional to the histidine content (two in the tomato T1 form, six in theAspergillus form), suggesting that accessible histidine residues do not have active-site functions in these pectinesterases, but contribute to the overall structural stability. Lack of His roles in common between the enzyme forms is in agreement with the structures of pectinesterases having no conserved His residues.  相似文献   
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Aeolian dunes controlled by regional climate have been formed in many coastal areas of the Mediterranean Sea during the Quaternary. Generally, they are formed under a landward-blowing wind, and comprise numerous reworked penecontemporaneous shallow-marine carbonate grains. Along the eastern mid-Adriatic Sea, late Pleistocene aeolian and alluvial sands occur as isolated patches in karstic depressions on several islands and the Pelje?ac Peninsula. At most localities, the sands consist of a mixture of mostly carbonate rock fragments and siliciclastic material. A higher proportion of shallow-marine bioclasts was found only at one locality. The terrestrial material was transported to the coastal area by at least two rivers: paleo-Cetina and paleo-Neretva River, and was subsequently reworked and transported by wind, resulting in aeolian deposition. Sandy units of various thicknesses exhibiting sharp erosional bedding planes and cross-bedding are interpreted as representing aeolian dunes and sand sheets controlled by a complex wind regime. The mineralogical composition at almost all localities indicates near-river flood plains as the main sand source. Although the area was affected by strong winds blowing landward and parallel to the coast, they significantly deviated due to the local topography produced by the tectonically deformed and karstified carbonate basement. In this way, the late Pleistocene aeolian deposits on the mid-Adriatic islands differ from deposits from most Quaternary Mediterranean coastal aeolian belts, as they contain very small quantities of penecontemporaneous shallow-marine carbonate grains and were deposited by winds blowing in varying directions instead of prevailing landward-blowing winds.  相似文献   
286.
Aqueous ethanol mixtures are studied through molecular dynamics simulations with the focus on exploring how various force field models reproduce the association and its influence on selected thermo-physical properties of these mixtures. The most important conclusion seems to be the inadequacy of all classical force fields to reproduce the very peculiar shape of the excess enthalpy of these mixtures, as a function of the ethanol concentration, neither quantitatively nor qualitatively. The Kirkwood–Buff (KB) integrals calculated using the simulation data follow the same trends as the experimental ones. This suggests complicated correlation of the excess enthalpy with the concentration fluctuation and clustering in these mixtures. The KB force field shows better overall agreement with experimental results than the other studied models.  相似文献   
287.
Three fluoranthenes and one substituted fluoranthene, 2,2-dimethyl-2H-dibenzo[cd,k]fluoranthene, were investigated using the unrestricted symmetry-broken and complete active space methods. It was shown that four Kekuléan hydrocarbons are diradicals, implying that their ground state is a triplet. In the energetically less favorable singlet state these hydrocarbons exhibit pronounced diradical character. This occurance is explained with the tendency of the investigated molecules to delocalize their π-electrons. This leads to aromatic stabilization which is stronger than destabilization due to unpaired electrons. Our results for 2,2-dimethyl-2H-dibenzo[cd,k]fluoranthene are in excellent accord with experimental findings of McMaster et al. concerning this compound.  相似文献   
288.
Cone photoreceptor cell death in inherited retinal diseases, such as Retinitis Pigmentosa (RP), leads to the loss of high acuity and color vision and, ultimately to blindness. In RP, a vast number of mutations perturb the structure and function of rod photoreceptors, while cones remain initially unaffected. Extensive rod loss in advanced stages of the disease triggers cone death by a mechanism that is still largely unknown. Here, we show that secondary cone cell death in animal models for RP is associated with increased activity of histone deacetylates (HDACs). A single intravitreal injection of an HDAC inhibitor at late stages of the disease, when the majority of rods have already degenerated, was sufficient to delay cone death and support long-term cone survival in two mouse models for RP, affected by mutations in the phosphodiesterase 6b gene. Moreover, the surviving cones remained light-sensitive, leading to an improvement in visual function. RNA-seq analysis of protected cones demonstrated that HDAC inhibition initiated multi-level protection via regulation of different pro-survival pathways, including MAPK, PI3K-Akt, and autophagy. This study suggests a unique opportunity for targeted pharmacological protection of secondary dying cones by HDAC inhibition and creates hope to maintain vision in RP patients even in advanced disease stages.Subject terms: Neuroscience, Neurological disorders  相似文献   
289.
Remains of Albertona balkanica from the Early Miocene clays of eastern Serbia have shifted the range boundary of this species in direction of Central Europe. The peculiarities in tooth morphology were used for comparison and defining of the possible evolutionary connection with other representatives of fossil Ochotonidae. Due to the similarity with fauna of Aliveri in Greece, the association of small mammals of Snegotin (which includes Albertona) was included in the MN4 zone.  相似文献   
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