Percutaneous balloon mitral valvuloplasty in eight pregnant women with severe mitral stenosis.

Normal gestation is associated with a hyperdynamic adaptive state. The circulatory changes represent an additional burden on the cardiovascular system of women with rheumatic mitral stenosis (MS). Life-threatening complications can occur in pregnant women with severe MS. We successfully performed percutaneous balloon mitral valvotomy (PMV) in eight pregnant patients (mean age 28 +/- 6.9 years, range 21-38 years). Pregnancy mean age was 24.6 +/- 6.5 weeks. Five patients were in NYHA functional class III and three patients were in class IV. Emergency PMV seemed to be life saving to both mother and foetus in one case. All patients but one had pliable valves. PMV was achieved using the double balloon transseptal technique. To protect the foetus from radiation, the patient's pelvic-abdominal area was shielded and left ventriculography was not performed. The total mean time of PMV was 72 +/- 19 min and that of fluoroscopy was 16.6 +/- 7.8 min. Gorlin's mitral valve area increased from 0.83 +/- 0.15 to 2.4 +/- 0.34 cm2 and the cardiac index from 3.1 +/- 0.77 to 4.2 +/- 0.79 l.min-1.m-2. Left atrium pressure decreased from 29 +/- 10 to 14 +/- 5 mmHg and mitral valve gradient from 21 +/- 7 to 6 +/- 3 mmHg. There were no complications or residual MS. At a mean follow-up of 13.2 +/- 9.4 months, all patients were in NYHA class I and had a normal course of pregnancy. The eight women delivered healthy full-term babies. At 1-25 months post-partum follow-up, the eight infants had shown normal growth and development.(ABSTRACT TRUNCATED AT 250 WORDS)     

Amino acid sequence of the plasma membrane ATPase of Neurospora crassa: deduction from genomic and cDNA sequences.

The plasma membrane of Neurospora crassa contains an electrogenic H+-ATPase (EC 3.6.1.35), for which we have isolated and sequenced both genomic and cDNA clones. The ATPase gene is interrupted by four small introns (58-124 base pairs). It encodes a protein of 920 amino acids (Mr, 99,886) possessing as many as eight transmembrane segments. The Neurospora ATPase shows significant amino acid sequence homology with the Na+,K+- and Ca2+-transporting ATPases of animal cells, particularly in regions that appear to be involved in ATP binding and hydrolysis.     

A ph mesh refinement method for optimal control

A mesh refinement method is described for solving a continuous‐time optimal control problem using collocation at Legendre–Gauss–Radau points. The method allows for changes in both the number of mesh intervals and the degree of the approximating polynomial within a mesh interval. First, a relative error estimate is derived based on the difference between the Lagrange polynomial approximation of the state and a Legendre–Gauss–Radau quadrature integration of the dynamics within a mesh interval. The derived relative error estimate is then used to decide if the degree of the approximating polynomial within a mesh should be increased or if the mesh interval should be divided into subintervals. The degree of the approximating polynomial within a mesh interval is increased if the polynomial degree estimated by the method remains below a maximum allowable degree. Otherwise, the mesh interval is divided into subintervals. The process of refining the mesh is repeated until a specified relative error tolerance is met. Three examples highlight various features of the method and show that the approach is more computationally efficient and produces significantly smaller mesh sizes for a given accuracy tolerance when compared with fixed‐order methods. Copyright © 2014 John Wiley & Sons, Ltd.     

Poly(methacrylates) with Pendant Benzoquinone Units – Monomer Synthesis,Polymerization, and Electrochemical Behavior: Potential New Polymer Systems for Organic Batteries

Redox‐active polymers became the focus of attention in the field of organic electronics during the last decade. Quinoide systems are intensively studied in this field. Although benzoquinones are generally known as radical scavengers, certain monomers can be polymerized by radical polymerization techniques. For this purpose, methacrylate functionalities are attached to the redox‐active quinone moiety. A free‐radical polymerization technique is applied utilizing AIBN as initiator. The molar mass can be adjusted by the choice of an appropriate solvent system. Electrochemical investigations of these new monomers and polymers, in particular cyclic voltammetry, are performed in aqueous and non‐aqueous electrolytes in the dissolved and solid states, showing the potential usefulness of the system for applications in organic radical batteries.

     

Genetic and environmental influences on total plasma homocysteine and its role in coronary artery disease risk

BackgroundElevated levels of total plasma homocysteine are a risk factor for atherosclerotic disease.AimsThe rationale behind this study is to explore the correlation between degree and site of coronary lesion and hyperhomocysteinemia in Lebanese CAD patients and assess environmental and genetic factors for elevated levels of total plasma homocysteine.MethodsA total of 2644 patients were analyzed for traditional CAD risk factors. Logistic regression was performed to determine the association of hyperhomocysteinemia with degree and site of coronary lesions controlling for risk factors. Environmental and genetic factors for hyperhomocysteinemia were analyzed by logistic regression using a candidate gene approach.ResultsTraditional risk factors were correlated with stenosis. Hyperhomocysteinemia associated with increased risk of overall stenosis, and risk of mild and severe occlusion in major arteries. Hyperhomocysteinemia and hypertension were highly correlated suggesting that hyperhomocysteinemia acts as a hypertensive agent leading to CAD. Diuretics and genetic polymorphisms in MTHFR and SLCO1B1 were associated with hyperhomocysteinemia.ConclusionsHyperhomocysteinemia is a medical indicator of specific vessel stenosis in the Lebanese population. Hypertension is a major link between hyperhomocysteinemia and CAD occurrence. Genetic polymorphisms and diuretics’ intake explain partly elevated homocysteine levels. This study has important implications in CAD risk prediction.     

Molecular dynamics of ultradian glucocorticoid receptor action

In recent years it has become evident that glucocorticoid receptor (GR) action in the nucleus is highly dynamic, characterized by a rapid exchange at the chromatin template. This stochastic mode of GR action couples perfectly with a deterministic pulsatile availability of endogenous ligand in vivo. The endogenous glucocorticoid hormone (cortisol in man and corticosterone in rodent) is secreted from the adrenal gland with an ultradian rhythm made up of pulses at approximately hourly intervals. These two components - the rapidly fluctuating ligand and the rapidly exchanging receptor - appear to have evolved to establish and maintain a system that is exquisitely responsive to the physiological demands of the organism. In this review, we discuss recent and innovative work that questions the idea of steady state, static hormone receptor responses, and replaces them with new concepts of stochastic mechanisms and oscillatory activity essential for optimal function in molecular and cellular systems.     

Timing of diagnosis of 47,XXY and 48,XXYY: A survey of parent experiences

47,XXY/Klinefelter syndrome is the most common sex chromosomal aneuploidy, yet 64% of males with this condition go undiagnosed. 48,XXYY is less common and there is less known about the diagnosis. The objective of this study is to describe the diagnosis experiences of parents of males with 47,XXY and 48,XXYY. Parents of 89 males with 47,XXY and 76 males with 48,XXYY completed a survey that gathered data about their experiences leading to a diagnosis, including the current age of the child, age at diagnosis, reasons for initial concern, and the specialists providing the diagnosis. In the 47,XXY cohort diagnosed postnatally, 59% presented with developmental delay, with a mean age at first parental concern of 5.2 years and mean age of diagnosis at 10.0 years. The remaining 41% presented with endocrinologic issues with a mean age at first concern of 19.1 years and mean age of diagnosis at 21.1 years. In the 48,XXYY group, 93% presented with developmental delay, with mean age at first parental concern of 2.4 years and mean age of diagnosis at 7.6 years. Hence, the average time from initial parental concern to diagnosis of 47,XXY or 48,XXYY ranges from 2 to 5 years, with those presenting with developmental issues having a longer lag to diagnosis compared to those presenting with endocrinologic issues. Increased awareness of the developmental, psychological, and medical features of 47,XXY and 48,XXYY is important to facilitate timely diagnosis and initiation of appropriate screenings and treatments that are important for optimal outcomes. © 2013 Wiley Periodicals, Inc.