Diffusion tensor magnetic resonance imaging-derived myocardial fiber disarray in hypertensive left ventricular hypertrophy: visualization, quantification and the effect on mechanical function

Left ventricular hypertrophy induced by systemic hypertension is generally regarded a morphological precursor of unfortunate cardiovascular events. Myocardial fiber disarray has been long recognized as a prevalent hallmark of this pathology. In this chapter, ex vivo diffusion tensor magnetic resonance imaging is employed to delineate the regional loss of myocardial organization that is present in the excised heart of a spontaneously hypertensive rat, as opposed to a control. Fiber tracking results are provided that illustrate in great detail the alterations in the integrity of cardiac muscle microstructure due to the disease. A quantitative analysis is also performed. Another contribution of this chapter is the model-based assessment of the role of the myofiber disarray in modulating the mechanical properties of the myocardium. The results of this study improve our understanding of the structural remodeling mechanisms that are associated with hypetensive left ventricular hypertrophy and their role

A Test Rig to Measure the Static Load Performance of a Water Lubricated Thrust Bearing

A thrust bearing test rig experienced a catastrophic failure while operating with gas bearings. After many repairs, the test rig is in operating condition with water-lubricated bearings. Previous work details the failure and several initial repairs and modifications. Further modifications include manufacturing two rotors, repairing the main housing, aligning the motor shaft and test rotor, upgrading the water pipeline system, developing a static load system, installing instrumentation, and developing means of data acquisition. Presently, the revamped system has rotated to a speed of 5 krpm. Measurements of the free-free mode natural frequencies and lateral mode shapes of the rotor-coupling system show that the rotor and quill shaft operate as a unit. Once assembled, water lubricates the bearings to lift and support the test rotor connected to the motor through its coupling. Impact loads identify the system fundamental natural frequency and damping ratio for operation without rotor speed or active thrust bearings. The flexibility of the quill shaft commands the location of the system lateral natural frequency (~ 93 Hz) and its low damping ratio. XLTRC2® based predictions agree well with the measured natural frequency and identified damping ratio. The water lubricates the radial bearings to lift the test rotor again as the motor accelerates the rotor to 5 krpm. During this operation, the rotor motion is synchronous and does not excite the first natural frequency. While operating at speeds up to 5 krpm, the system did not reach its first critical speed. Measurements show the thrust bearing axial clearance increases as the water supply pressure increases, max. 4.14 bar(g), for operation with a constant axial load and at null or low rotor speed (3 krpm). As the imposed axial load increases, the operating clearance decreases exponentially. The decreasing operating clearance causes an increased flow resistance across the film lands, resulting in a reduced flow rate. As the flow rate decreases, there is a lower pressure drop across each orifice, resulting in an increase in recess pressure. The derived axial stiffness increases as the axial clearance decreases or the water supply pressure increases. XLHydroThrust® uses the thrust bearing geometry to generate predictions of thrust bearing performance. The predictions accurately describe the influence of the load and supply pressure on the thrust bearing performance; however, there are discrepancies between the magnitudes of the predictions and the magnitudes of the measurements at a high axial load (low axial clearance). The average percent difference between the predicted and measured magnitudes of supply flow rate, flow rate through inner diameter, axial clearance, and recess pressure ratio change from 2% to 47%, 7% to 73%, 25% to 53%, and 7% to 18%, respectively, as the applied axial load increases from its minimum to maximum magnitude. Thus, there is a significant increase in difference between the predicted and measured magnitudes as the applied axial load increases. Future work includes measurements of static and dynamic load performance of a water lubricated hybrid thrust bearing

Changes in Grape Maturity Induced by Spraying Ethanol

Three different ethanol solutions were sprayed onto Cabernet Sauvignon (Vitis vinifera L.) clusters during the ripening period: 2.5, 5 and 10% by volume in water. Controls were sprayed with water alone. Three different times of spraying were also tested: 8, 10 and 13 weeks post-flowering. One of the observed changes was a lower titratable acidity in grape samples at harvest, when the clusters were sprayed with ethanol at 10 weeks, in comparison with controls. The wines made with grapes treated with ethanol after mid-veraison, had higher ODs at 520 nm than did the controls. This may due to a combined effect of red pigment levels and acidity. In addition, following malolactic fermentation, the acidity levels of wines made with ethanoltreated grapes were slightly higher than those made with the control grapes. Spraying ethanol at 13 weeks post-flowering increased the berry weight by 10% at harvest without decreasing the °Brix value. The corresponding wines had similar degrees of alcohol. This observation was made for the first time in 2001

Bericht über die "1. Sanktionsstudie"

Die vorliegende empirische Studie (Beobachtung, Interviews und schriftliche Befragung) zur Sanktionsproblematik am Arbeitsplatz kommt zu folgenden Ergebnissen: (1) Im Betrieb werden weitaus mehr positive Sanktionen gewünscht, als die Leiter bewußt anwenden. (2) Die Kollegen streben besonders nach mündlichem Lob für ihre Leistungen. (3) Ausgebliebene, erwartete Anerkennung wird meist als Kritik oder Abwertung empfunden. (4) Bestimmte Verhaltensweisen werden sehr stark als negative Sanktionen empfunden (kühles und abweisendes Verhalten, das Ausbleiben von Leistungsbewertungen, der Gesprächston, das Nichtbeachten der eigenen Meinung durch den Vorgesetzten). (pmb

An elevated level of TSH might be predictive of differentiated thyroid cancer

Suppression therapy of thyreostimulin (TSH) using thyroid hormones improves survival of subjects operated for differentiated thyroid cancer. The TSH level might be different depending on the type of nodule. The objective of this study was to compare retrospectively the TSH level between two groups of subjects who underwent total thyroidectomy for a nodule, matched on sex, ethnicity, age and biological method of TSH measurement, one whose final histology was benign and one malignant. There was no significant difference between the two groups in terms of age, sex, family history of thyroid disease or thyroid autoimmunity. The subjects, whose final histology was malignant, had a mean TSH level significantly higher than subjects with benign disease (1.55 mU/l versus 0.96 mU/l, P=0.003). Cancer risk was greater when the TSH was in the upper tertile of normal range. There was no correlation between the risk of thyroid cancer and age, sex, family history of thyroid disease, or menopausal status. The relative risk of having thyroid carcinoma was higher when the margins of nodules were blurred or in the presence of microcalcifications. These data confirm a trend toward baseline values of TSH higher in subjects with a thyroid-differentiated cancer. However, we could not define a preoperative threshold that would reliably determine the malignant or benign nature of the nodule

Zinc deficiency: a frequent and underestimated complication after bariatric surgery

BACKGROUND: Although zinc deficiency is common after bariatric surgery, its incidence is underestimated. The objective was to monitor zinc and nutritional status before and 6, 12 and 24 months (M6, M12 and M24) after gastric bypass (Roux-en-Y gastric bypass), sleeve gastrectomy and biliopancreatic diversion with duodenal switch (DS) in patients receiving systematised nutritional care. METHODS: Data for 324 morbidly obese patients (mean body mass index 46.2 ± 7.3 kg/m(2)) were reviewed retrospectively. The follow-up period was 6 months for 272 patients, 12 months for 175, and 24 months for 70. Anthropometric, dietary and serum albumin, prealbumin, zinc, iron and transferrin saturation measures were determined at each timepoint. RESULTS: Nine percent of patients had zinc deficiency pre-operatively. Zinc deficiency was present in 42.5% of the population at M12 and then remained stable. Zinc deficiency was significantly more frequent after DS, with a prevalence of 91.7% at M12. Between M0 and M6, variation in plasma prealbumin, surgery type and zinc supplementation explained 27.2% of the variance in plasma zinc concentration. Surgery type explained 22.1% of this variance between M0 and M24. Mean supplemental zinc intake was low (22 mg/day). The percentage of patients taking zinc supplementation at M6, M12 and M24 was 8.9%, 20.6% and 29%, respectively. CONCLUSIONS: Reduced protein intake, impaired zinc absorption and worsening compensatory mechanisms contribute to zinc deficiency. The mechanisms involved differ according to the type of surgery and time since surgery. Zinc supplementation is necessary early after bariatric surgery, but this requirement is often underestimated or is inadequate

NDR Kinases Are Essential for Somitogenesis and Cardiac Looping during Mouse Embryonic Development

Studies of mammalian tissue culture cells indicate that the conserved and distinct NDR isoforms, NDR1 and NDR2, play essential cell biological roles. However, mice lacking either Ndr1 or Ndr2 alone develop normally. Here, we studied the physiological consequences of inactivating both NDR1 and NDR2 in mice, showing that the lack of both Ndr1/Ndr2 (called Ndr1/2-double null mutants) causes embryonic lethality. In support of compensatory roles for NDR1 and NDR2, total protein and activating phosphorylation levels of the remaining NDR isoform were elevated in mice lacking either Ndr1 or Ndr2. Mice retaining one single wild-type Ndr allele were viable and fertile. Ndr1/2-double null embryos displayed multiple phenotypes causing a developmental delay from embryonic day E8.5 onwards. While NDR kinases are not required for notochord formation, the somites of Ndr1/2-double null embryos were smaller, irregularly shaped and unevenly spaced along the anterior-posterior axis. Genes implicated in somitogenesis were down-regulated and the normally symmetric expression of Lunatic fringe, a component of the Notch pathway, showed a left-right bias in the last forming somite in 50% of all Ndr1/2-double null embryos. In addition, Ndr1/2-double null embryos developed a heart defect that manifests itself as pericardial edemas, obstructed heart tubes and arrest of cardiac looping. The resulting cardiac insufficiency is the likely cause of the lethality of Ndr1/2-double null embryos around E10. Taken together, we show that NDR kinases compensate for each other in vivo in mouse embryos, explaining why mice deficient for either Ndr1 or Ndr2 are viable. Ndr1/2-double null embryos show defects in somitogenesis and cardiac looping, which reveals their essential functions and shows that the NDR kinases are critically required during the early phase of organogenesis

Distribution of adipose tissue: Quantification and relationship with hepatic steatosis and vascular profiles of type 2 diabetic patients with metabolic syndrome

AimAs the distribution of fat is increasingly related to cardiovascular events, we examined whether or not abdominal-fat quantification using magnetic resonance imaging (MRI) software is reliable, and whether or not it is related to clinical markers of fat distribution as well as to metabolic and vascular status. Methods We recorded the anthropometric measurements of 34 obese type 2 diabetic patients with metabolic syndrome. The patients were enrolled to evaluate their abdominal (visceral and subcutaneous) adipose tissue by single-slice L3–L4 MRI. Manual and automated analyses were compared. The relationships between anthropometric measurements, biological markers and intima-media thickness of the common carotid artery were also assessed. Results We validated the automated software to quantify abdominal-fat deposition with MRI compared with manual measurements (r2 = 0.95). The waist-to-hip-circumference ratio (WHR) was the only clinical parameter that correlated with the proportion and quantity of visceral and subcutaneous abdominal-adipose tissue evaluated by MRI (r = 0.60). In addition, fat repartition as evaluated by WHR was related to hepatic steatosis parameters (ferritin and ALAT) and to intima-media thickness, whereas simple waist circumference was not a determinant in these obese patients. We also showed that the adiponectin-to-leptin ratio was related to adipose tissue distribution. Conclusion Distribution of abdominal fat, as evaluated by MRI, can be reflected by clinical determination of the WHR. Differences in regional accumulations of abdominal fat may be specifically related to variations in the risks of steatosis and vascular rigidity among obese type 2 diabetic patients

Hypercalcémie sévère après substitution d’une carence prolongée en vitamine D chez une malade ayant une hyperparathyroïdie primaire

International audienc