bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shunt Thrombosis Prevention in Hemodialysis Patients — A Double-Blind, Randomized Study: Pentoxifylline vs Placebo
Authors: Radmilović A. , Borić Z. , Naumović T. , Stamenković M. , Muśikić P. 
Published: November 2007

Previous studies demonstrated a high incidence of local thrombosis in patients in whom external arteriovenous shunts were used for vascular access. This procedure provides, therefore, a useful model for the evaluation of potential antithrombotic agents. The effect of the hemorheologically and hemostasiologically active drug Pentoxifylline on the incidence of thrombosis of arteriovenous shunts (Ramires shunt) was investigated in a long-term, double-blind, placebo-controlled study in 51 patients on chronic hemodialysis. The two treatment groups were comparable in age, sex, concomitant medication, and dialysis program (three times per week for four hours). Drugs known to affect platelet function or coagulation were excluded, with the exception of heparin, during the dialysis procedure. All shunts were placed in the forearm and inserted into the distal part of the radial artery and basilic antebrachial vein. Simultaneously, for medical reasons, in all patients an arteriovenous fistula was performed (proximal part of radial artery and cephalic antebrachial vein). Shunt thrombosis was assumed when the flow in the shunt discontinued under visual and auscultatory control. Thrombi were documented by physical removal from the arterial part of the shunt by use of gentle suction or by complete shunt thrombosis (both arterial and venous part of the shunt). Thereafter, the patients' trial period terminated. The total number of thrombi during the observation period was 44 in the pentoxifylline group (26 patients), compared with 82 in the placebo group (25 patients). The mean number of thrombi per patient was 1.69±1.29 in the pentoxifylline group, significantly lower than that in the placebo group (3.28±1.99 / p < 0.05). Further, the periods until the occurrence of first thrombosis (in the arterial part of the shunt) and complete shunt thrombosis were assessed per patient in days: in the pentoxifylline group the first shunt thrombosis occurred after 34.8±6.7 days (x±s.e.) and with placebo after 16.7±4.4 days (p < 0.05). The complete thrombosis was recorded in the pentoxifylline group after 46.8±6.5 days and with placebo after 24.6±5.8 days (p < 0.05). These findings indicate that pentoxifylline medication markedly reduced the incidence of thrombosis of arteriovenous shunt and distinctly extended the shunt survival period, suggesting an effective antithrombotic property of the drug.
Functional Vascular Disorders: Treatment with Pentoxifylline
Authors: Neirotti Massimo , Longo Flavia Flavia , Molaschi Mario , Macchione Carmine , Pernigotti Luigi 
Published: November 2007

A group of 11 female patients (mean age 33.7±8 years) with a clearly proven primary Raynaud's syndrome of up to five years' duration were subjected to a two-month oral treatment with 3 x 400 mg pentoxifylline per day. The following parameters were studied without and with exposure to cold conditions: hemody namics (finger photoplethysmography), red cell deformability (filtration test), various clotting variables (prothrombin activity, antithrombin III, plasma fi brinogen, partial thromboplastin time, thrombin time, thrombelastogram), and clinical symptomatology. After treatment 7 of the 11 patients showed a distinct improvement of pe ripheral blood flow and of symptoms (decrease or removal of asphyxia attacks, pain, color change) under basal conditions, as well as after exposure to cold. Red cell filtration was significantly (p < 0.05) improved, increasing by 35% un der normal conditions and by 30% after exposure to cold. Positive changes were also found in respect to antithrombin III (increase) and plasma fibrinogen (de crease). The thrombelastogram was unchanged. Clinical and instrumental improvements were probably ascribable to better microcirculatory flow due to increased red cell deformability, reduced viscosity, and decreased fibrinogen, all capable of influencing in various degrees the blood flow at the microcirculatory level.
Hemorheology in Surgery—A Review
Authors: Müller R. , Mušikić P. 
Published: November 2007

The rheological behavior of blood and its components under physiologic and pathophysiologic conditions is reviewed, with a focus on the type and extent of pathohemorheological changes in surgical patients during hospitalization and thereafter, as well as their clinical consequences with regard to thromboembolic complications. During the operation and the postoperative period various hemorheological and hemostasiological alterations acquire clinical signifcance: 1. hyperreagibility of platelets with increased aggregation and adhesion ten dency 2. changes in fibrinogen, albumin, and globulin concentrations, which af fect viscosity and red cell aggregation 3. impairment of red cell deformability 4. increase in clotting factors 5. disturbance of fibrinolysis characterized by diminution of plasmatic plas min and increase in antiplasmin activity In addition, anesthetic techniques have also been shown to affect he morheological and hemostasiological parameters. The complex pattern of pathohemorheological and hemostasiological changes shows that thromboembolism in the course of surgical interventions is provoked by multifactorial disorders. Thrombosis prevention should, therefore, counteract both hemorheological and hemostasiological disturbances. Since pathohemorheological and pathohemostasiological changes are al ready detectable before, and increase during operation, preventive measures should start before the surgical intervention to obtain maximum benefit. Therapeutic possibilities for the avoidance of these multifactorial distur bances are discussed with particular reference to pentoxifylline, which satisfies the complex requirements of a hemorheologically and hemostasiologically active therapeutic agent.
Clinical Application of Laser Doppler Flowmetry for Measurement of Cutaneous Circulation in Health and Disease
Authors: Winsor Travis , Haumschild Daniel J. , Winsor David W. , Wang Ying , Luong Thanh N. 
Published: November 2007

The cutaneous laser Doppler device (LDF) was employed to determine its usefulness in differentiating the circulation of the feet in normal subjects from that in patients with arteriosclerosis obliterans. It is shown that the laser Doppler frequencies correlated well with results from venous occlusion plethysmography, which measured volume rate of flow. Thus, one can determine volume rate of flow by the simple Doppler method. There was a linear relationship between these two methods of measurements. Using the LDF method, it was determined that normal individuals have toe flows that on the average are 42% of finger flows in supine resting subjects. In peripheral vascular disease of the lower extremities, the LDF measurements showed a decreased circulation in the large toes when the patients are supine and the lower extremities flat. The results between health and disease are exaggerated by elevating the feet, at which time the diseased circulation falls to extremely low values compared with those of normal subjects. A similar decrease in skin oxygen tension in the diseased lower extremities was observed when the limbs were elevated.
Evaluation of Enzymes in Serum and Cerebrospinal Fluid in Cases of Cerebrovascular Accidents
Authors: Nand Nitya , Gupta S. , Sharma M. , Khosla S.N. , Saini A.S. , Lal H. 
Published: November 2007

Gamma glutamyl transpeptidase (GGTP), glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) were measured serially in the serum and cerebrospinal fluid (CSF) of 22 patients with fresh stroke and an equal number of age- and sex-matched healthy control subjects. It was observed that levels of these enzymes in the CSF of control subjects were very low but were significantly elevated (p < 0.001) in both serum and CSF in patients with stroke. The elevation was greater in the CSF than in the serum and was maximum during the first four days of stroke. Thereafter, the enzymatic activity declined. Of all these enzymes, GGTP in CSF correlated best with the clinical picture. It was possible to differentiate between the ischemic and hemorrhagic type of stroke on the basis of CSF levels of GGTP ( > 60.0 units in hemorrhagic stroke). There was no correlation between GGTP levels in CSF and serum or among GOT, GPT, and GGTP in CSF. It can be concluded, therefore, that estimation of GGTP in CSF is helpful not only in predicting the degree of cerebral damage and functional outcome of the patient following stroke but also in differentiating the type of stroke.
Primary Lower Extremity Telangiectasias — Relationship of Size to Color
Authors: Biegeleisen Ken 
Published: November 2007

Sclerotherapy remains the treatment of choice for primary telangiectasias of the lower extremities, a half century after the treatment was first devised. No substantial improvements have been made, largely because little or no attention has been paid to the underlying physiology. Evidence is presented that these vessels are dilated by virtue of their proximity to small arteriovenous communications. This would explain the response these vessels demonstrate when injected with sclerosing solutions, as well as the relationship between their size and their color, which is documented by objective and subjective measurements. Two novel methods of treating telangiectasias with existing sclerosing solutions are described, and the characteristics of an ideal sclerosant for these vessels are proposed.
Changes in Hemodynamics Due to the Contrast Medium During Left Ventriculography
Authors: Koeda Toshihiko , Motegi Itaru , Ichikawa Takashi , Suzuki Tomoyuki , Kato Masataka 
Published: November 2007

Seventeen patients with heart diseases examined by left ventricular angiography were divided into two groups consisting of those with a clinical history of heart failure (CHF+) and those without (CHF-). Changes in hemodynamics, circulating blood volume, and plasma volume due to injection of the contrast medium were studied, and the following results were obtained. Both the CHF - and CHF + groups showed an increase in heart rate after injection of the contrast medium, but a statistically significant difference (p < 0.05) was noted only at one and two minutes after angiography in both groups. Left ventricular systolic pressure decreased after injection of the contrast medium in both groups, but the CHF+ group required a longer time for recovery. In the CHF - group, the left ventricular end-diastolic pressure increased slightly after injection of the contrast medium, but in the CHF+ group it increased markedly with a statistically significant difference (p < 0.01). Stroke volume, measured by a noninvasive, continuous cardiac output monitor according to the impedance method, increased upon injection of the contrast medium in the CHF— group. However, in the CHF+ group it decreased, although no statistically significant difference was noted in either group. Cardiac index increased markedly upon injection of the contrast medium in the CHF— group with a statistically significant difference (p < 0.01), but hardly any change was observed in the CHF+ group. Circulating blood volume increased in both groups ten minutes after injection of the contrast medium, but whereas the CHF - group showed no statistically significant increase and had a gradual reduction to the original state an hour afterward, a statistically significant increase over original values in the CHF+ group was observed at ten minutes and one hour after injection. The mean value of the CHF+ group was statistically significantly higher than that of the CHF- group at one hour after injection. Circulating plasma volume showed statistically significant mean increases over original values in both groups at ten minutes and at one hour after injection of the contrast medium. The mean value of the CHF+ group was statistically significantly higher than that of the CHF- group at one hour after injection. In conclusion, patients with heart failure, in comparison with those without, showed different changes in hemodynamics, circulating blood, and plasma volumes caused by the contrast medium, and thus it was necessary to be cautious when the contrast medium was injected into patients with a history of heart failure.
Anomalous Left Coronary Artery from the Pulmonary Artery : Effect of Coronary Anatomy on Clinical Course
Authors: Tyrrell Michael J. , Duncan Walter J. , Hayton Robert C. , Bharadwaj Baikunth B. 
Published: November 2007

Nine children and 1 adolescent with anomalous left coronary artery from the pulmonary trunk (ALCA) were studied between 1970 and 1982. Serial angiographic and hemodynamic data are compared with the clinical course. Four patients had separate conus coronary arteries with a major contribution to collateral flow. Eight patients survived various surgical procedures with 1 late death, 1 awaits operation, and 1 died in infancy. The authors' data show a significant potential for improvement in left ventricular function as shown by an increase in LV ejection fraction on medical therapy alone (5/6 patients), including all 4 with separate conus coronary arteries. The authors conclude that medical treatment alone may be indicated for a time in selected patients with ALCA, and a subgroup with a separate conus coronary artery may have a more favorable natural history.
Serum Ionized Calcium A Predictor of Therapeutic Response To Slow Calcium Channel Blockade in Essential Hypertension
Authors: Midtbø Kjell , Hals Ottar 
Published: November 2007

In 20 patients with mild to moderate essential hypertension, serum ionized calcium was determined before and after four weeks of treatment with 240 mg verapamil sustained release bid. Pretreatment systolic blood pressure was inversely correlated to serum ionized calcium (r = — 0.44, p = 0.05). Mean blood pressure was significantly (p < 0.001) reduced (from 161/100 to 145/88 mm Hg), but mean serum ionized calcium did not change during treatment (from 1.23 to 1.24 mmol/L). A significant inverse correlation (r = -0.56, p = 0.01) was found between pretreatment serum ionized calcium and reduction in systolic blood pressure during verapamil treatment. Thus serum ionized calcium in untreated essential hypertensive patients may predict the blood pressure response to the slow calcium channel blocker verapamil.
Restriction by Nitrendipine of Excessive Concentration of Free Intracellular Calcium Ions in Ventricular Myocardium of Hypertensive Rats
Authors: Gasser Robert , Frey Markus , Young Kun Byon  , Fleckenstein-Grün Gisa 
Published: November 2007

In earlier investigations it has been found that high arterial blood pressure of salt-sensitive DAHL rats (DAHL-S) that received a diet con taining 8% NaCl could be normalized by chronic treatment with specific calcium antagonists, as for instance, nitrendipine or anipamil. Parallel measurements on heart and arterial vasculature with atomic absorption spectrometry revealed that there was a rise in absolute calcium content upon development of hypertension, whereas under the influence of ni trendipine, not only the blood pres sure and heart weight but also myocardial (and arterial) tissue cal cium content remained in the physio logic range. In the present study, an additional determination of the free intracellu lar calcium ion concentration with Ca-sensitive microelectrodes was car ried out. For technical reasons, the measurements were restricted to iso lated resting rat papillary muscles (stretched to optimal length in a per fusion bath of 1.5 ml at 30°C in nor mal Tyrode solution). The impale ment of the electrodes was considered adequate when the heights of Ca po tential and membrane potential were constant for more than twenty min utes. In order to produce severe sys temic hypertension, a group of six-week-old DAHL-S rats was fed with an 8% NaCl diet over five weeks. Another group of DAHL-S rats received additionally 150 mg/kg nitrendipine twice a day orally. Salt- resistant DAHL-R rats, also fed with an 8% NaCl diet, served as controls. The findings of this preliminary study are as follows (n = 5 in each group):
Serum Copper, Magnesium, Zinc, Calcium, and Potassium Changes Following Acute Myocardial Infarction
Authors: Bakos Salem N. , Ahmed Hamid K. , Nasser Tariq A. K. 
Published: November 2007

When analyzed within seventy-two hours of admission to the coronary care unit, the mean values of serum copper and magnesium were lower in patients with acute myocardial infarction than in noncardiac patients. Zinc values showed no difference. Because the reduction of serum copper in males was statistically significant, the authors suggest that a lowering of serum copper, especially in males, can be useful in the diagnosis of recent infarction and could possibly have other impli cations. Significant elevations of serum calcium and of serum potassium were also demonstrated.
Experimental Evaluation of the Mitroflow Pericardial Heart Valve Prosthesis. Part II. Pathologic Examination
Authors: Hassoulas J. , Rose A.G. 
Published: November 2007

The results of the morphologic and histopathologic examination of 37 bovine pericardial heart valve prostheses that were retrieved after experimental im plantation in Chacma baboons for periods of one to twelve months are pre sented in this study. The implanted prostheses consisted of 33 Mitroflow valves, size 21 mm, that belonged to four different groups according to the method of preparation of the pericardium (process I to IV) and 4 commercially available Ionescu-Shiley valves, size 19 mm. All implantations were in the mitral position, except 1 Mi troflow and 1 Ionescu-Shiley prosthesis, which were implanted in the tricuspid position. Moderate or abundant noninfected thrombotic deposits were found on the cusps of 13 of the 33 Mitroflow valves (39%). The Ionescu-Shiley valves shared this tendency, perhaps to a lesser extent, for the formation of thrombus on the valve cusps. Results of transmission electron microscopy, scanning electron mi croscopy, and calcification analysis are also presented. In this experimental study, the authors did not identify any significant char acteristics in the Mitroflow bovine pericardial heart valve prosthesis that would lead to improved or extended durability of this device over the commercially available Ionescu-Shiley bovine pericardial heart valve prosthesis and probably over any other glutaraldehyde-treated bioprosthesis. They would suggest, therefore, that any clinical investigations of the prosthesis be undertaken very cautiously.
Efficacy of Indobufen in the Treatment of Intermittent Claudication
Authors: Signorini G.P. , Salmistraro G. , Maraglino G. 
Published: November 2007

The aim of this trial was to assess the activity of indobufen compared with placebo in peripheral occlusive arterial disease of the lower limbs of atheroscle rotic or diabetic origin. Fifty-two outpatients were admitted to the randomized, double-blind study and were given either an indobufen 200-mg tablet (28 sub jects) or placebo (24) for six months. Painfree walking distance on a treadmill at a constant speed (4 km/h) and slope (10°) was assessed before and after three and six months' treatment. The painfree walking distance before treatment with indobufen or placebo averaged 153 ± 23.02 (mean ± SE) and 199 ± 30.58 (mean ± SE) meters respectively. After six months' treatment with active drug or placebo, this parameter reached 610 ± 115.36 (p < 0.01) and 243 ± 32.49 (p > 0.05) meters respec tively. The difference between the two treatments was statistically significant in favor of indobufen (p < 0.01 Dunn's test).
The Interdependence of Hypertension, Calcium Overload, and Coronary Spasm in the Development of Myocardial Infarction
Authors: Gasser Robert N. A. 
Published: November 2007

It is a well-known fact that sys temic hypertension is one of the ma jor risk factors for myocardial in farction (MI). Extensive studies on hypertensive rats revealed that cal cium is excessively elevated in the myocytes, as well as in the coronary artery wall of these animals, which results in a higher resting tension and a stronger contractile response of those muscle strips. Over many years coronary spasm has been claimed by various authors to be greatly involved in the patho physiology of the early phase of acute MI (AMI). It can be shown that thrombocytes that aggregate at the injured vessel wall next to athero slcerotic plaques release vasocon strictive factors that induce series of severe spasms at the sites with defec tive endothelium that end up in myocardial infarction; the patho physiologic pathway is called the thromboischemic reentry mechan ism. This local contractile response may be enhanced in the presence of systemic hypertension since intracel lular calcium is elevated in the coro nary smooth muscle. On the other hand, it has been shown that heart muscle fibers un dergo severe alterations finally re sulting in necrotization, as soon as free calcium ions penetrate exces sively through the sarcolemma mem brane into the myoplasm so that the capacities of the calcium binding or extrusion processes become overpow ered ; this is especially the case during ischemia. Since free intracellular cal cium is already ten times elevated in the myocytes in systemic hyperten sion, the myocardium may be more vulnerable to further calcium over load owing to the ischemia and ne crotization is augmented. The elevation of intracellular Ca of the myocytes of the cardiovascular system in systemic hypertension en hances the pathologic response of the coronary arteries and the myocar dium. This work gives a complete overview of the pathophysiologic principles involved in AMI occurring with systemic hypertension.
The Vascular Resistance of Arterial Stenoses in Series
Authors: Kilpatrick D. , Webber S.D. , Colle J-P. 
Published: November 2007

The vascular resistance of stenoses in series has been studied in vitro by use of fiber optic laser Doppler anemometry to measure the cross-sectional areas of the stenoses. Pressure gradients across each of the stenoses were measured while both the severity and the separation of the stenoses were altered. The individual resistances were compared with the combined resistance. Resistance at a stenosis is a nonlinear function of the severity of the stenosis. The resistance is a complex function of the perfusion pressure and the cross-sectional area of the stenosis and cannot be accurately predicted from a single plane angiographic image. With multiple stenoses an approximate assessment of the combined effect can be obtained by summing the value of the resistance for each stenosis but not the degree of the stenoses. The nonlinear relationship of resistance to stenosis severity means that if one stenosis is more severe than the other, the combined effect can be regarded as the same as the effect of the more severe stenosis acting by itself. The distance between the stenoses does not change their combined effect.