bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production of glucolipids and specialty fatty acids from sophorolipids by Penicillium decumbens naringinase: Optimization and kinetics
Authors: Saerens Karen , Van Bogaert Inge , Soetaert Wim , Vandamme Erick 
Published: February 2009

AbstractIn view of global environmental concerns and the awakening to the exhaustibility of our natural resources, an increasing importance of biologically derived surfactants can be expected in the near future. Enzymatic modification of these biosurfactants allows to improve their characteristics and so extend their application field. In view of this, glucolipids are interesting substrates e.g., for the synthesis of new glycolipids with increased biological activity. Here, we describe the optimization of glucolipid production from Candida bombicola sophorolipids by Penicillium decumbens naringinase and show that the enzyme might be useful for production of specialty fatty acids as well. Optimum conditions for production of glucolipids were found to be pH 7.0 and 50°C with a yield of 80% (w/w) glucolipids after 3 h of incubation. The Km for sophorolipids was 1.67 mM, while Vmax was 0.035 mM sophorolipids/min. At pH 3.0, glucolipids were immediately further hydrolyzed and completely converted to fatty acids after 24 h of incubation, offering a biological route to the synthesis of unique specialty fatty acids. The Km for glucolipids was 11 mM while Vmax was 0.21 mM glucolipids/min. Glucose inhibited the enzyme in a competitive way with KI around 10‐15 mM glucose. Surfactant properties of the produced glucolipids were comparable to those of the acidic sophorolipids.
The effect of bacterial glutathione S‐transferase on morpholine degradation
Authors: Emtiazi Giti , Saleh Tayebe , Hassanshahian Mehdi 
Published: February 2009

AbstractGlutathione S‐transferases (GSTs) constitute a large family of enzymes that catalyze the addition of glutathione to endogenous, or xenobiotic, often toxic electrophilic compounds. The effect of this enzyme in facilitating polychlorinated biphenyls degradation has been studied previously. Here the effects of induced cell‐free extracts of Acinetobacter calcoaceticus and Pseudomonas aeruginosa (grown on hexadecane), and E. coli BL21 (induced with pGEX‐2T plasmid on isothiopropylgalactoside) were recruited to facilitate morpholine degradation by Mycobacterium and were compared with non‐induced strains. The results showed that all induced strains had significantly more GST activity compared to non‐induced ones, and the strain with most GST activity, A. calcoaceticus BS, removed morpholine faster. Eukaryotic GST gene expressed in E. coli BL21 also could facilitate morpholine degradation by Mycobacterium, The same experiments performed with cell‐free extracts of non‐induced cells did not show any significant effects on morpholine removal. These results showed that there is a correlation between GST activity and acceleration of morpholine degradation.
Polymehr Perspektiven!
Authors: Roll J. , Sadowski G. 
Published: February 2009

AbstractFür Absolventen von Bachelorstudiengängen wie Chemie, Chemieingenieurwesen oder Materialwissenschaften gibt es mit dem Masterstudiengang Polymerwissenschaften nun ein Angebot, das ihre Chancen am Arbeitsmarkt deutlich verbessert. Die Kombination der Polymerchemie mit Themenstellungen der Ingenieur‐ bzw. Materialwissenschaften eröffnet zusätzliche Perspektiven auf dem Arbeitsmarkt.
Ein perfekter Kleber
Authors: Harrer Roswitha 
Published: February 2009

AbstractWas Geckos können, dazu sind wir noch lange nicht in der Lage: Einen Klebstoff zu benutzen, der wie die Gecko‐Fußzehen stark am Untergrund haftet, sich leicht ablöst, haftet, sich ablöst. Nun wurde das bislang genaueste Abbild der Klebe‐Struktur an den Zehen der Geckofüße hergestellt. Haftung und Lösung gelangen durch Ab‐ und Anschalten eines Magnetfeldes.
Fetal cardiovascular system as influenced by maternal smoking
Authors: Asmussen I. 
Published: February 2009

AbstractPrimary prevention of atherosclerosis should be initiated early in life, preferably in childhood. Nevertheless, it tends to be forgotten that a child has existed for nine months before birth, and that the newborn child might already have been exposed to agents capable of causing vessel damage.Studies of the umbilical artery, umbilical vein, and vessels of the placental villi (2, 3, 4, 5, 6) revealed that, in this portion of the fetal cardiovascular system, severe damage to the vessel wall is associated with maternal tobacco smoking during pregnancy. These alterations within the fetal cardiovascular system were never found in the children of non‐smoking mothers. If similar changes occur in the other vessels of the newborn child, which it seems reasonable to expect, they might give rise to sequelae later in life. It should therefore strongly be advocated that pregnant women abandon tobacco smoking.
Patient profile and follow‐up in medically and surgically treated young adults with myocardial infarction
Authors: Mcmartin D. E. , Masden R. R. , Sohi G. S. , Flowers N. C. 
Published: February 2009

AbstractTwenty‐four young patients with myocardial infarction (average age 32.1 years) undergoing coronary arteriography after infarction were followed for an average of 33 months after catheterization. Prior inferior infarction was a predictor of two and three vessel coronary occlusive disease. Prior anterior infarction patients had a 64% incidence of single vessel coronary occlusive disease. Improvement in anginal symptoms over the follow‐up period from the time of catheterization for the entire group was 69%. Employment at follow‐up was excellent in both medically and surgically treated patients (80%). Cardiac mortality from the time of catheterization was extremely low (4%).
Lidoflazine in the management of angina pectoris
Authors: Bloem Th. J. J. M. , Vermeulen A. , Reneman R. S. 
Published: February 2009

AbstractThe effect of lidoflazine administration (120 mg t.i.d. for 9 weeks) on work tolerance (bicycle ergometer), frequency of anginal attacks, and nitroglycerin consumption was investigated in 28 male patients with stable angina pectoris in a combined single‐blind/double‐blind study. Lidoflazine increased work tolerance and reduced the frequency of anginal attacks and nitroglycerin consumption. The higher work tolerance level was reached at maximal heart rate and heart rate‐systolic blood pressure product values similar to those before treatment. The values of these variables after 3 min of exercise at 60 W, however, were significantly lower after treatment with lidoflazine. These findings indicate that the heart is performing more economically during lidoflazine treatment. The improved work tolerance can probably be ascribed to lidoflazine and not to a training effect because of the significant reduction of this variable in the patients allocated to placebo as compared to those remaining on lidoflazine treatment. The side effects were generally slight. In one patient the prolongation of the QT interval due to lidoflazine resulted in rhythm disturbances.
Myocardial metabolism of cyclic 3,5‐adenosine monophosphate as influenced by dipyridamole and theophylline in patients with coronary heart disease
Authors: Hombach V. , Behrenbeck D. W. , Tauchert M. , Gil‐Sanchez D. , Jansen W. , Hötzel J. , Niehues B. , Hilger H. H. 
Published: February 2009

AbstractIn a total of 16 individuals, 4 females and 12 male patients ranging from 36 to 54 years, with proven coronary heart disease, hemodynamic parameters and coronary blood flow (argon method) were measured at rest and after administration of dipyridamole, 0.5 mg/kg body weight, and theophylline, 0.24 g i.v. Simultaneously, blood samples were taken from the arterial and coronary venous blood for determinations of oxygen content and concentrations of cyclic 3,5‐adenosine monophosphate (cAMP) and lactate. Thus, myocardial oxygen consumption and uptake or release of cAMP and lactate could be calculated according to the Fick principle.After administration of dipyridamole, heart rate and cardiac index slightly increased together with a decrease in arterial pressure. Myocardial blood flow significantly increased, whereas myocardial oxygen consumption remained unchanged during the dipyridamole period. In nine patients myocardial release of cAMP and lactate could be observed during the dipyridamole action, whereas in the remaining seven patients there were only insignificant changes of release or uptake of cAMP and lactate in the dipyridamole and theophylline periods. Six of nine patients in the first group revealed specific anginal complaints corresponding to the release of cAMP and lactate, whereas only two patients in the non‐cAMP‐releasing individuals had characteristic angina pectoris.These data suggest that dipyridamole may induce myocardial ischemia with anginal complaints and that, under certain circumstances, myocardial release of cAMP as well as lactate might serve as biochemical correlates of these ischemic conditions.
Reliability and reproducibility of interpretation of 99m technetium pyrophosphate myocardial scintigrams
Authors: Mason J. W. , Myers R. W. , Goris M. L. , Doherty P. , Alderman E. L. , Kriss J. P. 
Published: February 2009

AbstractThe interpretations of 156 99mtechnetium pyrophosphate myocardial scintigrams by four observers were analyzed in order to determine the reliability and reproducibility of the subjective process of reading scintigrams. The scintigrams were scored on an integral scale from 0 to 4, depending upon the degree of myocardial radionuclide accumulation, and the site and nature of uptake were specified. Exact agreement upon score was generally poor but approximate concurrence of interpretation was good (90.4 and 92.5% inter‐ and intra‐observer agreement, respectively). There was somewhat less agreement on scintigrams with the higher scores of 3 and 4 (83.3 and 78.0%, respectively). A high level of concurrence upon the differentiation between diffuse and localized uptake, and upon the site of uptake, was found. We conclude that only approximate rather than exact agreement of individual readers' interpretations can be expected in this subjective technique, that scintigrams with higher degrees of radionuclide accumulation produce slightly greater observer disagreement, and that variability of interpretation could account for some of the diagnostic inaccuracy of 99mtechnetium pyrophosphate myocardial scintigraphy.
The prognosis of anterior myocardial infarction revisited: A community‐wide study
Authors: Kennedy H. L. , Goldberg R. J. , Szklo M. , Tonascia J. A. 
Published: February 2009

AbstractA study was carried out in metropolitan Baltimore in which the short‐ and long‐term prognosis of 655 patients with anterior myocardial infarction (MI) was compared with that of 520 patients with inferior/posterior MI. The study was performed on a community‐wide basis in two time periods before the clinical introduction and widespread use of beta‐blockade therapy. After simultaneous adjustment for several socio‐demographic and clinical variables, the in‐hospital case fatality rate was greater for patients with anterior (27.5%) than for those with inferior/posterior MI (22.9%) (p<0.05). Similarly, for those discharged alive from the hospital and followed up for as long as 10 years, patients with infarction of the anterior wall had a significantly poorer long‐term survival than that of patients with infarction of the inferior/posterior wall (p<0.05). These results suggest that closer surveillance should be directed at patients with anterior myocardial infarction, both during the acute phase and after hospital discharge.
Evaluation of aortic and mitral valve regurgitation by radionuclide ventriculography: Comparison with the method of sandler and dodge
Authors: Kress P. , Geffers H. , Stauch M. , Nechwatal W. , Sigel H. , Bitter F. , Adam W. E. 
Published: February 2009

AbstractThe present investigation was undertaken to introduce a quantitative scintigraphic method for evaluation of regurgitation and to compare it with the generally accepted quantitative method of Sandler and Dodge (Sandler et al., 1963).Radionuclide ventriculography was carried out after injection of 20 mCi 99mtechnetium‐labeled red blood cells. Time‐activity curves were obtained from the left and right ventricular regions. The ratio (A) of end‐diastolic‐end‐systolic count‐rate differences for the left and right ventricles was calculated. The ratio (A) was compared with a hemodynamic ratio (Ah) determined after the method of Sandler and Dodge (1963) with the stroke volume of the left ventricle measured angiographically, and the stroke volume of the right ventricle measured by thermodilution.In 33 patients with aortic and mitral valve regurgitation we found a correlation of r= 0.75 between (A) and (Ah). Due to a broad range of normal values of (A) the sensitivity of the scintigraphic method is low. The specificity seems to be high, however, since in 64 patients with all types of heart diseases there were no false positive results.Comparing the described scintigraphic method with other modern or generally accepted methods, the principal advantages are noninvasiveness, good practicability, and the fact that important additional information about the functional state of the heart is gained. This is important in follow‐up studies in patients with chronic valvular incompetence.It seems that this method will become a valuable supplement to heart catheterization in the diagnosis of valvular heart disease and may partially replace invasive methods for measuring the regurgitation fraction.
Evaluation of Platelet Kinetics following Porcine and Mechanical Valve Replacement
Authors: Lee G. , Joye J. A. , Rose A. , Denardo S. , Kozina J. A. , Mason D. T. 
Published: February 2009

AbstractBecause thromboembolic pathogenesis in mechanical prosthetic valves (MP) might involve selective MP platelet consumption with consequent reduced platelet survival, it has been suggested that lowered platelet half‐life (T1/2) detection provides identification of postoperative thrombotic risk. Porcine heterografts (PH) possess less thromboembolic hazards than MP; thus, comparative evaluation of PH versus MP platelet T1/2 is germane to the test's thrombotic predictive value, yet platelet kinetics in PH require elucidation. Accordingly, 51chromium platelet T1/2 was determined in 16 patients with substituted valves (10 PH and 6 MP). Average platelet T1/2 in PH (2.9±0.6 d) was similar (p>0.05) to MP (3.2±0.6 d), and both were considerably lower (p<0.05) than platelet T1/2 in normal subjects (NL, 5.1±0.5 d). Furthermore, platelet T1/2 was below the lowest NL platelet T1/2 (4.0 d) in seven PH and three MP patients. Thus, frequency and extent of decreased platelet survival in PH are common and equal to MP. These results indicate that platelet half‐life does not afford thromboembolic predictability in patients with mechanical valves and, instead, favors prosthetic‐induced physical trauma causing abnormal platelet survival.
Changes in cardiovascular function induced by verapamil in healthy subjects and in patients with ischemic heart disease
Authors: Vincenzi M. , Morlino T. , Allegri P. , Barbieri E. , Cappelletti F. , Delio U. , Ometto R. , Maiolino P. 
Published: February 2009

AbstractAlterations in cardiovascular function induced by the acute intravenous administration of verapamil (5 or 10 mg) in 52 patients (29 with ischemic heart disease and 23 without heart disease) were evaluated with use of invasive techniques (right and left heart catheterization, left ventricular cineangiography, and coronary arteriography). The most significant changes were represented by a decrease in systemic vascular resistance and systemic arterial pressure, and an increase in heart rate and cardiac output.Contractility indexes were not depressed in either group, and altered ventricular wall motion tended to improve to a slightly smaller degree than in patients treated with nitroglycerin.The use of verapamil in patients with ischemic heart disease appears to be safe, and concern about the negative inotropic influences in humans no longer seems justified.
Influence of heart rate on systolic time intervals: Effects of atrial pacing versus dynamic exercise
Authors: Mertens H. M. , Mannebach H. , Trieb G. , Gleichmann U. 
Published: February 2009

AbstractThe effects of atrial pacing and dynamic exercise in the supine position on systolic time intervals (STI) were compared in 10 normals. In another group of 13 normals, the effect of exercise alone on STI was tested. A linear shortening of electromechanical systole (QS2) and left ventricular ejection time (LVET) with increasing heart rate was demonstrated with right atrial pacing and dynamic exercise in the frequency range between 60 and 140 beats/min. However, the shortening of LVET was significantly less (p<0.01) with exercise compared to pacing. This is explained by an increase in left ventricular stroke volume with exercise. The pre‐ejection period (PEP) was significantly (p<0.001) shortened with exercise, but there was no change with atrial pacing. Thus, changes in heart rate (HR) alone, without changes in the dynamic state of the heart, did not influence PEP.It is suggested that PEP at rest should not be corrected for heart rate. The supine exercise regression equations for correction of heart rate for LVET and PEP differ from both the resting and the upright exercise regression equations. With exercise a frequency correction of STI using regression equations should be abandoned. Instead, uncorrected STI at standard heart rates (e.g., 100, 110, and 130 beats/min) should be taken for comparison. Heart rate standardization should be employed using the formula
Left ventricular end‐diastolic pressure in evaluating left ventricular function
Authors: Iskandrian A. S. , Segal B. L. , Hamid HAKKI A. 
Published: February 2009

AbstractThere are several factors that could affect the left ventricular end‐diastolic pressure. These include heart rate, preload, afterload, pericardial or pleural pressure, diastolic properties of the left ventricle, and the left ventricular inotropic state. Recognition of these factors appears important when considering the left ventricular end‐diastolic pressure as an index of left ventricular function.
Hyperkalemia‐induced bundle branch block and complete heart block
Authors: Ohmae M. , Rabkin S. W. 
Published: February 2009

AbstractHyperkalemia was associated with complete heart block in one patient that resolved by first showing right bundle branch block and marked left axis deviation (left anterior hemiblock). Then the right bundle branch block resolved, leaving the marked left axis deviation that was present before the hyperkalemic episode. Another patient with hyperkalemia had right bundle branch block with marked left axis deviation, both of which disappeared with correction of the hyperkalemia. These findings suggest that hyperkalemia can depress conduction in the His‐Purkinje system and raise the possibility that hyperkalemia may induce complete heart block distal to the atrioventricular junction.
Thallium stress myocardial imaging: An evaluation of fifty‐eight asymptomatic males
Authors: Nolewajka A. J. , Kostuk W. J. , Howard J. , Rechnitzer P. A. , Cunningham D. A. 
Published: February 2009

AbstractThe possible value of myocardial imaging with 201thallium as a screening procedure for the detection of latent disease has not been previously shown. Fifty‐eight asymptomatic men underwent exercise 201thallium imaging together with a risk score profile based on the Framingham criteria for predicting future coronary events. Six subjects (10%) developed perfusion defects compatible with myocardial ischemia. The risk score for the population with an abnormal test was 7.7±2.9%, compared to 2.0±2.2% (p<0.001) for those men with normal tests. Three of the subjects with abnormal scans underwent selective coronary arteriograms; all three had normal coronary arteries. During a 30‐month follow‐up, all individuals remained physically active and free of cardiac symptoms.
Long‐term maintenance therapy with prazosin in congestive heart failure
Authors: Mehta J. , Miles D. , Iacona M. , Conti C. R. 
Published: February 2009

AbstractWe evaluated the effects of long‐term maintenance therapy with oral prazosin (6‐20 mg, mean 14±2 mg/d) in 14 patients with congestive heart failure. The patients were followed for 6±1 months. Eleven of the fourteen patients reported subjective improvement. Two patients required increased diuretics because of gain in body weight. Systolic blood pressure showed a slight but sustained decrease suggesting persistent vasodilator effect. Reductions in echocardiographic left ventricular end‐diastolic (6.35±0.25‐5.88±0.25 cm, p<0.05) and end‐systolic (5.16±0.35‐4.73 ±0.28 cm, p<0.05) diameters were observed at 2 months. However, the cardiothoracic ratio on chest x ray was unaltered. Maximum exercise tolerance time increased in eight patients (57%) during prazosin therapy. Improvement in exercise tolerance time was observed in patients with most marked clinical improvement, suggesting presence of cardiac reserve. Two patients died suddenly after reporting subjective improvement. This study shows sustained clinical improvement in most patients with heart failure treated with oral prazosin.
Anomalous right ventricular muscle bundle: Clinical pitfalls and extracardiac anomalies
Authors: Danilowicz D. , Ishmael R. 
Published: February 2009

AbstractSeven patients with anomalous right ventricular muscle bundle are presented to emphasize possible pitfalls in the clinical diagnosis as based on physical examination, chest x ray, and electrocardiogram. Echocardiography, on the other hand, revealed abnormalities in all four of the patients on whom the study was done. The echocardiogram was directly responsible for a change in diagnosis and referral for a cardiac catheterization in one patient who had been followed for 19 years with the clinical diagnosis of a small ventricular septal defect.
Myocardial injury and ck‐mb release during aortic valve surgery with selective coronary perfusion
Authors: Ström S. , Bendz R. , Olin C. 
Published: February 2009

AbstractThe postoperative serum activity of creatine kinase MB isoenzyme (CK‐MB) was studied in 25 patients undergoing isolated aortic valve replacement (Björk‐Shiley prosthesis). Hypothermia at 30° C and selective coronary perfusion (CP) were used for myocardial protection. Repeated electrocardiograms revealed no signs of perioperative myocardial infarction. In all patients, CK‐MB was detected in the serum. The CK‐MB as a percentage of total CK at peak CK‐MB [12±1 (mean±SEM)] was of the same magnitude as that found in acute myocardial infarction (AMI). Peak CK‐MB occurred 2±0 h after the end of surgery. Peak total CK occurred after 17±3 h, and the plasma half‐life for total CK was three times that of CK‐MB. Thus, the kinetics of serum CK differed from those in AMI, but were similar to those reported after coronary bypass operations. The release of CK‐MB, as well as of aspartate aminotransferase and thermostable lactate dehydrogenase, was related to the duration of aortic cross‐clamping (AC), with a marked increase after 90 min. In two subgroups with similar AC time, postoperative CK‐MB activity was higher in the subgroup with longer CP, indicating that CP as a method of myocardial protection may not be entirely beneficial.