Biochemical, histological and histochemical changes in Aristichthys nobilis Rich. liver exposed to thiamethoxam

Background and purpose: The aim of the present study was to investigate the effects of the insecticide thiamethoxam on some biochemical, histological and histochemical parameters of bighead carp liver (Aristichthys nobilis), which is an economically important fish species for aquaculture. Materials and methods: Different increasing concentrations of 6.6 mg l-1, 10 mg l-1 and 20 mg l-1 of the test chemical under laboratory conditions were tested for their toxicity on fish for 96. The hepatic activity of the enzymes lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) were measured. In addition, the hepatic histological structure was observed for alterations, as well as the lipid content was observed by histochemical staining. Results: It was determined that the enzymatic activity of the exposed fish was increased compared to the control group (p<0.05). Furthermore, the enzymatic activity was increased proportionally to the increasing thiamethoxam concentrations. The histological lesions, which were observed in the liver parenchyma, were degenerative and necrotic. The degenerative alterations were as follows: granular, balloon and fatty degeneration. The necrotic alterations in the fish liver were associated with presence of karyopyknosis, karyorrehsis and karyolysis, respectively. The histological alterations in the liver blood vessels were hyperemia and lymphocyte proliferation. Along with the established histological changes in the liver parenchyma, we found presence of fatty degeneration in the hepatocytes using Sudan III staining on cryostat sections. Conclusions: Our study shows that there is a relation between the concentration of the insecticide and biochemical changes, as well the severity of expression of the histological and histochemical alterations in the bighead carp liver. Overall, such experiments could be successfully applied in research and monitoring programs to study the effects of pesticides on fish

Cerebral blood flow imaging. Relation to blood rheology

Abstract A number of techniques allow imaging of the cerebral blood flow (CBF). Flow-sensitive time-of -flight (TOF) magnetic resonance imaging (MRI) demonstrates good representation of the flow but the extracranial hemodynamics could be assessed by color duplex ultrasound of the carotid arteries. Computerized tomography (CT), Xenon enhanced or CT perfusion with iodinated contrast, single-photon emission computed tomography (SPECT) with HMPAO, positron emission tomography (PET) with radiolabeled water, contrast perfusion-weighted and non-invasive MRI technique using continuous arterial spin labeling (CALS) provide precise assessment of cerebral perfusion with measurement of blood flow velocities. The contrast agents used have hemorheological and vessel wall effects. Keywords: Cerebral blood flow, Doppler ultrasound, functional neuroimaging, blood rheology _____________________________________________________________________________ Cerebral blood flow (CBF), is the blood supply to the brain in a given time. In an adult, CBF is typically 750 milliliters per minute or 15% of the cardiac output. This equates to 50 to 54 milliliters of blood per 100 grams of brain tissue per minute. The CBF is determined by a number of factors, such as viscosity of blood, vascular tone and the net pressure of the flow of blood into the brain, known as cerebral perfusion pressure (CPP), which is determined by the body&apos;s blood pressure (BP). CBF is equal to CPP divided by the cerebrovascular resistance (CVR): The cerebral autoregulation is a process, which aims to maintain adequate and stable CBF regardless of the changes of systemic BP or CPP. The stability of CBF is accomplished by altering the blood vessels diameter through constriction or dilatation The conventional neuroimaging methods -computed tomography (CT) and magnetic resonance imaging (MRI) are good enough to estimate the state of brain morphology. However the contemporary diagnosis and treatment options need: • To define the cerebral physiology by application of different stimuli (CO 2 inhalation, cognitive or movement tasks etc.), which lead to local CBF changes. • To identify areas of abnormal blood flow in cerebral pathology: stroke, vascular malformations, carotid stenoses or occlusions, traumatic brain injury, vascularized brain tumors, resistant epilepsy, psychiatric diseases. • To estimate the therapeutic choice and to do the CBF measurement as earlier as possible after the brain injury. • To monitor the effectiveness of contemporary thrombolytic therapy and surgical interventions. This important information for the therapeutic behavior is achieved by the so-called functional neuroimaging methods. The Doppler ultrasound is one of those methods. It provides information about the change of velocity and direction of moving erythrocytes in the major arteries of the neck and the proximal segments of intracranial arteries, and other parameters of blood flow in the examined vascular segment. It can thus identify and characterize stenosing arterial section or change in the direction of flow

Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p

Effect of alirocumab on mortality after acute coronary syndromes. An analysis of the ODYSSEY OUTCOMES randomized clinical trial

Background: Previous trials of PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitors demonstrated reductions in major adverse cardiovascular events, but not death. We assessed the effects of alirocumab on death after index acute coronary syndrome. Methods: ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) was a double-blind, randomized comparison of alirocumab or placebo in 18 924 patients who had an ACS 1 to 12 months previously and elevated atherogenic lipoproteins despite intensive statin therapy. Alirocumab dose was blindly titrated to target achieved low-density lipoprotein cholesterol (LDL-C) between 25 and 50 mg/dL. We examined the effects of treatment on all-cause death and its components, cardiovascular and noncardiovascular death, with log-rank testing. Joint semiparametric models tested associations between nonfatal cardiovascular events and cardiovascular or noncardiovascular death. Results: Median follow-up was 2.8 years. Death occurred in 334 (3.5%) and 392 (4.1%) patients, respectively, in the alirocumab and placebo groups (hazard ratio [HR], 0.85; 95% CI, 0.73 to 0.98; P=0.03, nominal P value). This resulted from nonsignificantly fewer cardiovascular (240 [2.5%] vs 271 [2.9%]; HR, 0.88; 95% CI, 0.74 to 1.05; P=0.15) and noncardiovascular (94 [1.0%] vs 121 [1.3%]; HR, 0.77; 95% CI, 0.59 to 1.01; P=0.06) deaths with alirocumab. In a prespecified analysis of 8242 patients eligible for ≥3 years follow-up, alirocumab reduced death (HR, 0.78; 95% CI, 0.65 to 0.94; P=0.01). Patients with nonfatal cardiovascular events were at increased risk for cardiovascular and noncardiovascular deaths (P<0.0001 for the associations). Alirocumab reduced total nonfatal cardiovascular events (P<0.001) and thereby may have attenuated the number of cardiovascular and noncardiovascular deaths. A post hoc analysis found that, compared to patients with lower LDL-C, patients with baseline LDL-C ≥100 mg/dL (2.59 mmol/L) had a greater absolute risk of death and a larger mortality benefit from alirocumab (HR, 0.71; 95% CI, 0.56 to 0.90; Pinteraction=0.007). In the alirocumab group, all-cause death declined wit h achieved LDL-C at 4 months of treatment, to a level of approximately 30 mg/dL (adjusted P=0.017 for linear trend). Conclusions: Alirocumab added to intensive statin therapy has the potential to reduce death after acute coronary syndrome, particularly if treatment is maintained for ≥3 years, if baseline LDL-C is ≥100 mg/dL, or if achieved LDL-C is low. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01663402

Agricultural Academy

abstract Petrova, S., I. velcheva, l.Yurukova and M.Berova, 2014. Plantago lanceolata l. as a biomonitor of trace elements in an urban area. Bulg. J. Agric. Sci., to get real information on environmental pollution with trace elements (al, cd, cr, cu, Pb and Zn) and their mobility in urban ecosystems, Plantago lanceolata l. plants and soil samples were collected in May 2010. Sampling sites were selected in urban areas with different anthropogenic impact (Plovdiv, Bulgaria). Significantly, elevated concentrations of Cd, Cr and Al were registered in all samples. Differences between trace element concentrations in sampled phytomass led to evaluation of the urban gradient theory in the context of the city of Plovdiv. the results of the investigation revealed the main problems and unfavorable factors, which affected urban vegetation. automobile transport was found to be the major source of contamination, followed by the industry. the contribution of some additional factors as canyon-street effect, wind rose, climate and topography of the region towards forming the environmental state was discussed. the approach used in our study could be successfully applied as a model to explore possibilities of using other herbaceous plant species for biomonitoring of the urban environmental status

Numerical analysis of 3D blood flow and common carotid artery hemodynamics in the carotid artery bifurcation with stenosis

The results for blood flow in the carotid artery bifurcation on the basis of numerical simulation of Navier-Stokes equations are presented in this study. Four cases of carotid bifurcation are considered: common carotid artery (CCA) bifurcation without stenoses and cases with one, two and three stenoses are also presented. The results are obtained by performing numerical simulations considering one pulse wave period based on the finite volume discretization of Navier-Stokes equations. The structures of the flow around the bifurcation are obtained and the deformation of the pulse wave from common carotid artery (CCA) to the internal carotid artery (ICA) and external carotid artery (ECA) is traced. The axial velocity and wall shear stress (WSS) distribution and contours are presented considering the characteristic time points. The results of the WSS distribution around the bifurcation allow a prediction of the probable sites of stenosis growth

Stenosis effects on the fluid mechanics of the common carotid artery bifurcation for unsteady flows

The time-varying blood flow in the common carotid artery (CCA) bifurcation is numerically studied on the basis of Navier-Stokes equations for four different cases, including cases with stenoses at different sites in the vicinity of the bifurcation. The cases studied were: (a) without stenoses, (b) with one stenosis upstream the bifurcation, (c) with two opposite stenoses upstream the bifurcation and (d) with an additional stenosis on the apex of the bifurcation. The mesh was generated via a geometry reconstruction and imported into a computational fluid dynamics (CFD) solver. The numerical results of the blood flow in the CCA bifurcation gave a detailed picture of the axial velocity and presented as velocity and vorticity magnitudes. More specifically, it was observed that the appearance of stenotic regions upstream the bifurcation affect both the velocity and vorticity characteristics, whereas a stenoses on the apex of the bifurcation seems to have a small effect on the vorticity characteristics downstream the flow