Factors correlated with left ventricular mass in hypertensive patients

Left ventricular hypertrophy (LVH) is an independent risk factor in hypertensive patient. THE AIM: Of our study is to evaluate prospectively the relationship between left ventricular mass and clinical, echocardiographical and ambulatory blood pressure data in hypertensive subjects. METHODS: We studied 88 hypertensive patient who underwent clinical and laboratory investigation, echocardiography and 24 hours ambulatory blood pressure monitoring. Correlations were made between these data and left ventricular mass. RESULTS: Clinical data, which correlated well with left ventricular mass, were duration of hypertension, systolic arterial pressure and pulse arterial pressure. In echocardiography left atrial area and left ventricular dysfunction correlated significatively with left ventricular mass. Data from 24 hours blood pressure monitoring as daytime systolic pressure, nighttimes diastolic pressure, ambulatory systolic pressure and ambulatory pulse pressure. CONCLUSION: In hypertensive patient, left ventricular mass correlated well with left atrial dilation and diastolic left ventricular dysfunction. It also correlated with 24 hours ambulatory blood pressure monitoring data.     

Percutaneous transluminal renal angioplasty in hypertension

The aim of our study was assess anatomical and functional results of renal artery angioplasty with and without stenting in 25 hypertensive patients (8 female and 16 male, 42.6 and 61.6 years old respectively) with significative renal artery stenosis (RAS) (atherosclerotic: 22; fibrodysplastic: 3). Eleven patients had simple angioplasty and 13 had stenting. The rate of angioplasty success was 96%. In the stent group, the anatomical result was better: 2% of residual stenosis versus 24% in the other group (p < 0.001). Restenosis occurred in 2 patients. Immediately after revascularisation arterial blood pressure decreased from 195/105 +/- to 150/85 +/- mmHg in-group without stent (p < 0.001) and from 190/100 to 145/85 mmHg in the group (p < 0.001). The value of serum creatinine concentration in patient with renal failure didn't change after revascularization.     

Bottom-up and top-down brain functional connectivity underlying comprehension of everyday visual action

How can the components of visual comprehension be characterized as brain activity? Making sense of a dynamic visual world involves perceiving streams of activity as discrete units such as eating breakfast or walking the dog. In order to parse activity into distinct events, the brain relies on both the perceptual (bottom-up) data available in the stimulus as well as on expectations about the course of the activity based on previous experience with, or knowledge about, similar types of activity (top-down data). Using fMRI, we examined the contribution of bottom-up and top-down processing to the comprehension of action streams by contrasting familiar action sequences with those having exactly the same perceptual detection and motor responses (yoked control), but no visual action familiarity. New methods incorporating structural equation modeling of the data yielded distinct patterns of interactivity among brain areas as a function of the degree to which bottom-up and top-down data were available.     

Performance of Sn-3.0Ag-0.5Cu Composite Solder with Kaolin Geopolymer Ceramic Reinforcement on Microstructure and Mechanical Properties under Isothermal Ageing

This paper elucidates the effect of isothermal ageing at temperature of 85 °C, 125 °C and 150 °C for 100, 500 and 1000 h on Sn-3.0Ag-0.5Cu (SAC305) lead-free solder with the addition of 1 wt% kaolin geopolymer ceramic (KGC) reinforcement particles. SAC305-KGC composite solders were fabricated through powder metallurgy using a hybrid microwave sintering method and reflowed on copper substrate printed circuit board with an organic solderability preservative surface finish. The results revealed that, the addition of KGC was beneficial in improving the total thickness of interfacial intermetallic compound (IMC) layer. At higher isothermal ageing of 150 °C and 1000 h, the IMC layer in SAC305-KGC composite solder was towards a planar-type morphology. Moreover, the growth of total interfacial IMC layer and Cu₃Sn layer during isothermal ageing was found to be controlled by bulk diffusion and grain-boundary process, respectively. The activation energy possessed by SAC305-KGC composite solder for total interfacial IMC layer and Cu₃Sn IMC was 74 kJ/mol and 104 kJ/mol, respectively. Based on a lap shear test, the shear strength of SAC305-KGC composite solder exhibited higher shear strength than non-reinforced SAC305 solder. Meanwhile, the solder joints failure mode after shear testing was a combination of brittle and ductile modes at higher ageing temperature and time for SAC305-KGC composite solder.