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Progressive Dilatation (progressive + dilatation)
Selected AbstractsNovel mutation and prenatal sonographic findings of glutaric aciduria (type I) in two Taiwanese familiesPRENATAL DIAGNOSIS, Issue 8 2002S. K. Lin Abstract Glutaric aciduria type I (GA I) is an autosomal recessively inherited inborn error with a defect of the enzyme glutaryl-CoA dehydrogenase (GCDH), which has never been diagnosed prenatally in Taiwanese patients. We present the prenatal sonographic findings and mutational analysis data of three children in two Taiwanese families. One patient from each family was diagnosed postnatally due to macrocephaly and neurological deterioration at 4,months and 10,months, respectively. The third child, sister of the first patient, was diagnosed prenatally at 11,weeks' gestation through chorionic villus sampling (CVS). Molecular analysis revealed that the fetus and child in Family 1 were homozygous for a common mutation, IVS10 -2A>C, which has not been reported in the Caucasian population. The patient in Family 2 was a compound heterozygote for IVS10 -2A>C and a novel mutation 749T>C (L238P). After genetic counseling, the couple decided to continue the second pregnancy. However, dilatation of quadrigeminal cistern (QC) and suspicious macrocephaly were noted at 30,weeks. Progressive dilatation of the QC associated with macrocephaly, fronto-temporal atrophy and wide space of perisylvian fissure were found in the follow-up scans. The affected girl was delivered at 37,weeks' gestation by cesarean section. Postnatal magnetic resonance imaging (MRI) studies confirmed the prenatal sonographic findings. With prenatal sonographic findings and mutational analysis presented in the present cases, the feasibility of prenatal diagnosis of GA I in high-risk pregnancy can not be overlooked. Copyright © 2002 John Wiley & Sons, Ltd. [source] Increasing intra-abdominal pressure increases pressure, volume, and wall tension in esophageal varicesHEPATOLOGY, Issue 4 2002Angels Escorsell Many daily activities cause acute elevations of intra-abdominal pressure (IAP). In portal hypertensive cirrhotic patients, increased IAP increases absolute portal pressure and azygos blood flow, suggesting that it may have detrimental consequences at the esophageal varices. The aim of this study was to investigate the effects of increased IAP on variceal pressure, size, and wall tension. Endosonography and a noninvasive endoscopic pressure gauge were used to measure variceal pressure, radius, wall tension, and volume in baseline conditions and after increasing IAP by 10 mm Hg using an inflatable girdle in 14 patients with cirrhosis and esophageal varices. Increasing IAP markedly increased variceal pressure (from 13.3 ± 4.2 to 17.4 ± 4.6 mm Hg; P = .0001) and radius (from 2.9 ± 1.0 to 3.9 ± 1.1 mm; P = .0001). Consequently, wall tension dramatically increased (from 38.7 ± 13.6 to 65.9 ± 23.8 mm Hg · mm, +78%; P = .0001). Variceal volume increased significantly from 1,264 ± 759 to 2,025 ± 1,129 mm3 (P = .0001). In conclusion, in portal hypertensive cirrhotic patients, increases in IAP have deleterious effects on variceal hemodynamics, markedly increasing the volume, pressure, and wall tension of the varices. Increases in IAP may contribute to the progressive dilatation that precedes the rupture of the varices in portal hypertension. [source] Heart failure: a hemodynamic disorder complicated by maladaptive proliferative responsesJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2003A. M. Katz Abstract Heart failure has traditionally been viewed as a hemodynamic syndrome characterized by fluid retention, high venous pressure, and low cardiac output. Over the past decade, however, it has become clear that because of deterioration and progressive dilatation (remodeling) of the diseased heart, this is also a rapidly fatal syndrome. The importance of prognosis came to be appreciated when clinical trials showed that therapy which initially improves such functional abnormalities, as high venous pressure and low cardiac output, often fail to improve survival, and that some drugs which improve hemodynamics worsen long-term prognosis. The latter is true for most vasodilators which, in spite of alleviating the adverse short-term consequences of high afterload, shorten survival. Notable exceptions are ACE inhibitors, whose vasodilator effects do not explain their ability to prolong survival; instead, these drugs slow both deterioration and remodeling of the failing heart. Inotropic agents, while providing immediate relief of symptoms, generally shorten long-term survival, whereas ,-blockers slow deterioration and remodeling, and reduce mortality. Aldosterone antagonists exert beneficial effects on prognosis that are not easily explained by their diuretic effects, but instead can be explained by their ability to inhibit signaling pathways that stimulate maladaptive hypertrophy, remodeling, apoptosis and other deleterious responses that cause deterioration of the failing heart. These and other findings demonstrate that heart failure is more than a hemodynamic disorder; these patients suffer from maladaptive proliferative responses that cause cardiac cell death and progressive dilatation that play a key role in determining the poor progressive in this syndrome. [source] Ultrasound measurements of the lateral ventricles in neonates: why, how and when?ACTA PAEDIATRICA, Issue 9 2010A systematic review Abstract Germinal matrix-intraventricular haemorrhage and subsequent post-haemorrhagic ventricular dilatation (PHVD) are frequently encountered complications in preterm neonates. As progressive dilatation of the lateral ventricles may be associated with elevated intracranial pressure, ultrasound measurements of ventricular size play a major role in the evaluation of neonates at risk of ventricular dilatation as well as in assessing the effect of intervention for PHVD. A systematic search was carried out in Medline and Embase to identify neonatal and foetal ultrasound studies on lateral ventricular size. This review presents an overview of the available data concerning neonatal reference values for lateral ventricular size, the influence of gender, ventricular asymmetry and the effect of the mode of delivery on the phenomenon of ventricular reopening following birth. Conclusion:, Serial cranial ultrasound measurements of the lateral ventricles play a key role in the early recognition and therapeutic evaluation of post-haemorrhagic ventricular dilation and can be of prognostic value in neonates with ventricular dilatation. [source] Blunting of rapid onset vasodilatation and blood flow restriction in arterioles of exercising skeletal muscle with ageing in male miceTHE JOURNAL OF PHYSIOLOGY, Issue 12 2010Dwayne N. Jackson Exercise capacity and skeletal muscle blood flow are diminished with ageing but little is known of underlying changes in microvascular haemodynamics. Further, it is not clear how the sympathetic nervous system affects the microcirculation of skeletal muscle with ageing or whether sex differences prevail in the regulation of arteriolar diameter in response to muscle contractions. In the gluteus maximus muscle of C57BL/6 mice, we tested the hypothesis that ageing would impair ,rapid onset vasodilatation' (ROV) in distributing arterioles (second-order, 2A) of old (20-month) males (OM) and females (OF) relative to young (3-month) males (YM) and females (YF). Neither resting (,17 ,m) nor maximum (,30 ,m) 2A diameters differed between groups. In response to single tetanic contractions at 100 Hz (duration, 100,1000 ms), ROV responses were blunted by half in OM relative to OF, YM or YF. With no effect in YM, blockade of ,-adrenoreceptors with phentolamine (1 ,m) restored ROV in OM. Topical noradrenaline (1 nm) blunted ROV in YM and YF to levels seen in OM and further suppressed ROV in OM (P < 0.05). To evaluate arteriolar blood flow, red blood cell velocity was measured in 2A of OM and YM; respective heart rates (353 ± 22 vs. 378 ± 15 beats min,1) and carotid arterial blood pressures (76 ± 3 vs. 76 ± 1 mmHg) were not different. Blood flows at rest (0.6 ± 0.1 vs. 1.6 ± 0.2 nl s,1) and during maximum dilatation (2.0 ± 0.8 vs. 5.4 ± 0.8 nl s,1) with sodium nitroprusside (10 ,m) were attenuated >60% (P < 0.05) in OM. Blood flow at peak ROV was blunted by 75,80% in OM vs. YM (P < 0.05). In response to 30 s of rhythmic contractions at 2, 4 and 8 Hz, progressive dilatations did not differ with age or sex. Nevertheless, resting and peak blood flows in YM were 2- to 3-fold greater (P < 0.05) than OM. We suggest that ageing blunts ROV and restricts blood flow to skeletal muscle of OM through subtle activation of ,-adrenoreceptors in microvascular resistance networks. [source] | |||||||||||||