bluuebunny/crossref_metadata_2025_split huggingface dataset:
Noninvasive Measurement of the Human Peripheral Circulation: Relationship Between Laser Doppler Flowmeter and Photoplethysmograph Signals from the Finger
Authors: Almond Nicholas E. , Jones Deric P. , Cooke Ernest D. 
Published: November 2007

Under certain conditions laser Doppler flowmeter (LDF) signals obtained from the finger pulp may appear very similar to those obtained by use of a direct current (dc) photoplethysmograph (PPG). A combined LDF/PPG system was used in conjunction with a circumference strain gauge as an index of vol ume change to identify the conditions in which the correlation between these signals was good. Simultaneous LDF and dc PPG measurements were made on 10 normal vol unteers by using arterial occlusion and on 7 normal subjects by using the Val salva maneuver at different elevations of the forearm and hand with respect to the midsternum. By altering the elevation of the upper limb the influence of venous filling on each of the signals during these maneuvers was observed. Since the dc PPG signal always appeared similar to the volume change indi cated by the circumference strain gauge, it is concluded that the dc PPG signal is related to blood volume change if allowance is made for the effects of blood oxygenation. In circumstances of low venous filling, however, blood volume changes correlate well with blood flow changes, producing the correlation be tween the dc PPG and LDF traces. The dc PPG signal may be used as a means of monitoring changes in blood flow in the finger only when venous filling is low and the return remains unre stricted. Thus, in investigations using this method, the relative position of the limb with respect to the heart should always be indicated. The LDF method appears to be a reliable indicator of blood flow changes in the microcirculation irrespective of the degree of venous filling.
Properties of Electromagnetic Field Focusing Probe
Authors: Yamanashi William S. , Yassa Nabil A. , Hill Deborah L. , Patil Angelo A. , Lester Patrick D. 
Published: November 2007

The electromagnetic field focusing (EFF) apparatus consists of a radio fre quency generator, solenoidal coil, and a hand-held or catheter probe. Applica tions such as aneurysm treatment, angioplasty, and neurosurgery in various models have been reported. The probe is operated in the near field (within one wavelength of an electromagnetic field source) of a coil inducing eddy currents in biological tissues, producing maximal convergence of the induced current at the probe tip. The probe produces very high temperatures depending on the wattage se lected for the given radio frequency of output power. The high temperature can be used in cutting, cauterizing, or vaporizing. The EFF probe is comparable to different types of lasers and to bipolar and mono polar cautery. The EFF probe can be used with catheters or endoscopes. Objec tives of this study were to determine what the thermal properties of the EFF probe are and how instrument parameters can be varied to obtain different temperatures in the tissue near the probe tip. In this study an F2 catheter was used as an insulated sheath and the tip of the guide wire was used as the probe tip. Different powers, wave forms, coil-to- probe distances, and probe-tip lengths were tested on a phantom that simulates tissue electrical properties. Some of the experiments were conducted under nor mal saline to simulate treatment of tissue with body fluids such as blood vessels or brain tissue under normal physiologic conditions. It is concluded that the EFF probe has the advantages of easy manipulation, relative safety, cost effectiveness, and a high degree of spatial control. Only at the point of contact do extremely high temperatures occur. Small volumes of heat dissipation occur around the tip, especially when the sinusoidal wave form is used. Temperatures delivered are related to power applied, coil-to-probe-tip distance, and probe-tip length.
Acute Hemorrhage and Oxygen Free Radicals
Authors: Prasad Kailash , Kalra Jawahar , Buchko Greg 
Published: November 2007

Oxygen free radicals are known to produce cellular injury. There are various mechanisms during hemorrhagic shock that can lead to an increase in the oxy gen free radicals, which would produce a loss of membrane integrity and a decrease in cardiac function and cardiac contractility. The authors studied the effect of acute hemorrhage and reperfusion on the hemodynamics, blood lac tate, and oxygen free radicals. Dogs were divided into two groups, group I, hemorrhagic shock and reinfu sion; group II, hemorrhagic shock and reinfusion with superoxide dismutase (SOD) and catalase treatment. The dogs were bled (50% of the estimated blood volume) over a period of five to twelve minutes. After an hour of bleeding, the shed blood was transfused over twenty to twenty-five minutes. Group II re ceived SOD (0.7 mg/kg, IV) and catalase (0.7 mg/kg, IV) within ten minues of bleeding. The hemodynamic measurements and collection of blood samples for measurement of oxygen free radicals and lactate were made before hemorrhage and at fifteen, thirty, and sixty minutes of hemorrhage and at fifteen, thirty, and sixty minutes after reperfusion of shed blood. There was a decrease in the cardiac function and index of myocardial con tractility associated with an increase in the blood lactate after hemorrhage in group I. Similar but less marked changes in these parameters were observed in group II. Recovery of hemodynamic parameters with reinfusion was better in group II as compared with that in group I. There was an increase in blood oxygen free radicals (superoxide anions) in group I, especially after reinfusion. No such changes were observed in group II. These results suggest that oxygen free radicals might be involved in acute hemorrhagic shock. Use of scavengers of oxygen free radicals might, therefore, be helpful in hemorrhagic shock.
Capillary Filtration and Ankle Edema in Patients with Venous Hypertension Treated with TTFCA
Authors: Belcaro Giovanni V. , Rulo Alex , Grimaldi Roberto 
Published: November 2007

The variation of capillary filtration rate (CFR), ankle circumference (AC), and ankle edema (AE) was evaluated in three groups of patients with venous hypertension (ambulatory venous pressure > 42 mmHg) and in a group of normal subjects before and after treatment for four weeks with Total Triterpenic fraction of Centella Asiatica (TTFCA), a venoactive drug acting on the microcirculation and on capillary permeability. Group A (20 patients) was treated with TTFCA 60 mg tid; Group B (20 patients) was treated with 30 mg tid; Group C (12 patients) was treated with placebo; and Group D (10 normal subjects) was treated with TTFCA 60 mg tid in an open study. Capillary filtration rate was assessed by venous occlusion plethysmography, ankle edema by a new system called AECT (Ankle edema coin tester). Subjective symptoms of venous hypertension were assessed by an analogue scale line considering four symptoms: swelling sensation, restless lower extremity, pain and cramps, and tiredness. CFR, AC, and AE were significantly higher in patients in comparison with normal subjects. After four weeks of TTFCA treatment there was a significant decrease of the abnormally increased CFR, AC, and AECT time in patients. This was also greater in the higher dose group. No significant change was observed in the placebo group and in normal subjects treated with TTFCA. Symptoms were also significantly improved in the two groups treated with the active drug according to the dose. No significant changes were observed in the placebo group. In conclusion the improvement of symptoms by TTFCA observed in patients with venous hypertension was well correlated with the improvement of CFR and ankle edema, and dose ranging showed that 180 mg/day is more effective in improving both symptoms and CFR.
Clinical Significance of Initial Systolic Hypertension After Myocardial Infarction
Authors: Katayama Tomoyuki , Yamasaki Hidefumi , Honda Yukiharu , Mori Mitsuhiro 
Published: November 2007

To clarify the clinical significance of acutely raised systolic blood pressure (SBP) after myocardial infarction, 60 patients who were admitted within six hours after onset were studied. Initial systolic hypertension was shown in 26.6% of patients. Time-corresponding plasma epinephrine and norepinephrine levels were abnormally high in 61% and 86% of patients respectively. These high values of catecholamines were not, however, specific to systolic hypertension. On the contrary, an inverse correlation was observed between systolic blood pressure and plasma epinephrine value. It appeared that the anxiety and stress of chest pain do not contribute to raising blood pressure through catecholamine liberation. In the high pressure group (SBP ≥ 160 mmHg), only 3 of 16 patients were classified into severer grades (III or IV) of Killip's classification. This proved to be statistically significant. A similar result was obtained in Lown's grading. Only 1 of 16 patients showed severe ventricular tachyarrhythmia. It appeared obvious from these data that patients who showed initial systolic hypertension are well protected from severe congestive heart failure and from life-threatening ventricular tachyarrhythmia in acute myocardial infarction.
Improved Left Ventricular Function in Myocardial Infarction Following Intravenous Thrombolytic Therapy with Acylated Plasminogen Activator
Authors: Ovsyshcher I. , Silber H. , Hausman M.I. , Margolis G. , Gueron M. 
Published: November 2007

Forty-six patients with acute myocardial infarction (MI) were treated within three hours of the onset of chest pain with an intravenous bolus (IV) of 30 units of anisolated plasminogen activator streptokinase complex (APSAC). Reperfusion was detected in 31 patients (67%) by clinical, electrocardiographic, and enzymatic criteria. The mean time elapsed between the onset of the chest pain to thrombolytic therapy was 114±53 minutes. Left ventricular ejection fraction (LVEF) was significantly better in patients with anterior and inferior myocardial infarction who had successful reperfusion, as compared with those who did not (48.8 ±13.0 vs 35.3 ±10.9, p<0.05 and 59.7±12.6 vs 47.9±15.3, p<0.05, respectively). The rate of reocclusion within three weeks was 22%. The overall one-year mortality was 4%. There were no serious adverse reactions following the thrombolytic treatment. Thus bolus IV injection of 30 units of APSAC is both safe and effective in preserving left ventricular function when given early in the course of acute myocardial infarction.
Successful Embolization of Multiple AV Foot Lesions—A Case History
Authors: Shetty P.C. , Beninson J. , Collison D.W. , Burke T.H. 
Published: November 2007

A 39-year-old white female with multiple arteriovenous malformations of the left foot had had surgical ligation on her left dorsalis pedis artery at age 12 with no clinical improvement. She was placed into a leotard at age 16 and was able to function but would tire very easily and her left foot was twice the size of her right one. In May 1988, she had four large feeder vessels off the posterior tibial artery and two off the anterior tibial artery embolized by use of 1,000 microns PVA particles, occlusive spring coils, and detachable balloons. Her foot shrunk and is now smaller than her normal right foot; she does not tire, and she now wears a knee length stocking to help prevent other channels from opening.
Effect of High-Dose Furosemide in Refractory Congestive Heart Failure
Authors: Marangoni Egidio , Oddone Alessandro , Surian Maurizio , Panciroli Claudio , Galloni Gianfranca , Masa Antonella , Caizzi Vincenzo , Belletti Sebastiano , Cominesi Walter Raimondi , Orlandi Mario 
Published: November 2007

High-dose firosemide is considered effective in primary renal sodium re tention but is not generally recom mended in congestive heart failure. In order to evaluate efficacy and safety of high-dose furosemide (>500 mg/day), the authors studied 20 patients (pts) resistant to therapy (including furose mide <500 mg/day) selected from 161 pts admitted for chronic heart failure. All refractory pts (15 men and 5 women, mean age sixty ± 12 years) were in NYHA class IV and showed hyponatremia (130±5 mEq/L) and im paired renal function (BUN 31±14 mg/dL, serum creatinine 1.3±0.3 mg/dL and BUN/creatinine ratio 23±7). In addition to digitalis, dopa mine, angiotensin-converting enzyme inhibitors, or vasodilators, IV high- dose furosemide (775±419 mg/day, 500-2000) was given for ten±five days under daily clinical and laboratory monitoring. Three pts died of low-output syn drome while 16 pts were upgraded to NYHA class III and 1 pt to class II; a mean weight reduction of 7.3±2.9 kg in ten+five days (0.80±0.4 kg/day) and a mean di uresis increase of 88±57% oc curred. The maximal dose of furosemide did not correlate with serum creatinine but did correlate with BUN/creatinine ratio (r = 0.78, p<.001). Pts were discharged on with chronic heart failure, and 43 % in the subgroup in NYHA class IV with hyponatremia. High dose furosemide was effective for rapid removal of ex cess water and salt in "furosemide-re sistant" congestive heart failure. The relationship between renal impair ment and maximal furosemide doses seems to confirm the role of renal pharmacokinetics in the appearance of furosemide resistance.
High Density Lipoprotein Inhibits Low Density Lipoprotein Binding and Uptake by Bovine Aortic Endothelial Cells
Authors: Alexander J. Jeffrey , Miguel Remedios , Graham Debra 
Published: November 2007

The antiatherogenic effect of high density lipoprotein (HDL) has been attrib uted to either an inhibition of cholesterol uptake or to reversed cholesterol transport from peripheral cells. In order to determine whether HDL competi tively blocks receptor-mediated low density lipoprotein (LDL) binding and up take, bovine aortic enothelial cells (BAECs) were cultured in Dulbecco's modified Eagles Medium (DMEM) containing 10% LDL-free fetal bovine serum, and incubated with 125I-LDL in concentrations of either 10 or 25 μg protein/mL. Varying amounts of HDL (0-200 μg/mL) were added to the media. Following a twenty-four hour incubation period at 37°C, 125I-LDL binding and uptake were measured. At the lower concentration of 125I-LDL, which represents high-affinity recep tor binding, there was no significant difference in either binding or uptake within the range of HDL concentrations studied. At the higher concentration of LDL, however, there was a marked inhibition of 125I-LDL binding (p<.006) and uptake (p<,001; ANOVA), which did not saturate at the highest HDL concentrations used. These data suggest that HDL does not influence high-affinity, receptor-me diated binding and uptake of LDL but that its effect is seen at a concentration of LDL representing nonspecific binding. The lack of saturation at increasing concentrations of HDL also indicates that HDL-receptor interaction is not essen tial for the effect.
The Effect on Skin Blood Flow of Short-Term Venous Hypertension in Normal Subjects
Authors: Cheatle T.R. , Chittenden S.J. , Coleridge Smith P.D. , Scurr J.H. 
Published: November 2007

Plugging of skin capillaries by activated white blood cells is one of the proposed mechanisms by which skin damage may be initiated in chronic venous insuffi ciency . The aim of this study was to determine whether a microcirculatory deficit was induced in the skin by raising the venous pressure proximally for thirty minutes. Seventeen subjects with no evidence of venous or arterial disease had laser Doppler velocimetry performed in the gaiter region of the leg; 8 different subjects had the measurement done on the dorsum of the hand. Peak hyperemic response following three minutes of ischemia was measured before and after a thirty-min ute period of sustained venous hypertension applied by a proximal tourniquet inflated to 80 mm Hg. A decrease in the peak flow: baseline flow ratio (median ratio 2.25 before, 1.70 after, p <0.02) and an increase in the time taken to reach maximal hyperemia (median time ten seconds before, twenty seconds after, p<0.01) were observed after the period of venous hypertension in the lower limb . The second parameter, but not the first, was significantly affected in the upper limb . The authors conclude that a microvascular deficit in the skin is demonstrable after a short period of venous hypertension . This is consistent with the white-cell- trapping theory, but other possible explanations are discussed.
Treatment of Hypertensive Urgencies with Oral Nifedipine, Nicardipine, and Captopril
Authors: Komsuoglu Baki , Şengün Bahtiyar , Bayram Ali , Komsuoglu Sezer Şener 
Published: November 2007

Sixty-five patients with unclomplicated hypertenive urgencies were treated in the emergency and cardiology departments with 20 mg nifedipine, 20 mg nicardipine, or 25 mg captopril in a randomized study. The study population consisted of 65 patients ranging in age from forty-one to seventy-one. Blood pressure and heart rate were assessed for six hours after intake of the antihyper tensive agents. Within sixty minutes nifedipine reduced blood pressure by an average of 74.7 mmHg for the systolic and 35.4 mmHg for the diastolic. Average heart rate increased significantly by 11.6 beats/min at within thirty minutes. Nicardipine and captopril produced equivalent falls in systolic (-81.6 and -79.4 mmHg) and diastolic (-37.3 and -33 mmHg) blood pressure respectively, but did not increase heart rate significantly. The antihypertensive effect of each drug was maintained until six hours after medication. In conclusion, nifedipine, nicardipine, and captopril show similar efficacy in the treatment of hypertensive urgencies. The authors believe that these drugs can be used as first-line therapy in the treatment of hypertensive urgencies safely and effectively.
Duplex Ultrasonographic Insonation and Visualization of Intracerebral Arteries
Authors: Montefusco-von Kleist Cheryl M. , Rhodes Barbara A. 
Published: November 2007

Until now, clinical, noninvasive interrogation of intracranial vessels has con sisted only of insonation via transcranial Doppler. Such devices have utilized a 2.0 MHz, continuous wave probe with Doppler spectral waveform display. Clinical application of these techniques has required precise location of cranial "windows" and has been hampered by the extreme anatomic variability of both cranial bony structures and intracerebral arteries. The lack of simultaneous in tracranial arterial visualization has limited the clinical applicability of transcranial Doppler technology. Recently, the authors have utilized a 2.25 MHz curved phased array probe with a pulsed Doppler to image and insonate simultaneously the intracerebral arteries. Colorflow imaging of both near- and far-field regions is the necessary first step for vessel localization and identification. Once this is accomplished, the image of each artery in turn is amplified and gray scale tuning is employed to permit direct visualization of the arterial walls and lumen. Pulsed Doppler waveform analysis is performed simultaneously and along the entire visible ar tery length. In this manner the arteries of both right and left hemispheres are examined in detail. We have found the duplex technique to be superior to the use of Doppler alone in the examination of intracerebral vessels. The ability to visualize and insonate simultaneously eliminates the uncertainty caused by anatomic varia tion. These advantages, long applied to the evaluation of peripheral vessels, are now available for use in the diagnosis of intracranial arterial disease.
Intracardiac Extension of a Calcified Ovarian Hemangioma— A Case Report
Authors: Tamburino Corrado , Russo Giovanni , Incognito Carmela , Battaglia Giuseppe , Monaca Vincenzo , Lomeo Alberto , Abbate Mauro 
Published: November 2007

The authors report a case of a fifty-five-year-old woman with clinical and echocardiographic diagnosis of right atrial myxoma. At fluoroscopy and phle bography a mobile calcified peduncle was appreciable originating from the left ovarian vein. This passed through the inferior cava to the right atrium where it wound round itself and extended into the right ventricle during diastole. The authors suspected the presence of a vascular leiomyoma. The tumor and its peduncle were removed by pulling through the right atri um during extracorporeal circulation. The site of origin was confirmed at pelvic surgery.
Evaluation of Reflex Cold Provocation by Laser Doppler Flowmetry in Clinically Healthy Subjects with a History of Cold Hands
Authors: Gasser P. , Müller P. , Mauli D. , Stäubli C. 
Published: November 2007

The aim of the present study was to investigate capillary blood flow and the reaction to cold provocation by means of laser Doppler flowmetry (LDF) and measurement of skin temperature at the fingertip of 39 healthy subjects who had a history of cold hands and feet but were free of any clinically significant vasospastic symptoms. A group of 39 sex- and age-matched healthy subjects without such complaints served as the control. The anamnestic complaints about cold hands and feet could be substantiat ed by the presence of a lower baseline skin perfusion and temperature. However, the maintenance of the normal range of reagibility to a reflex contractile stimu lus with an unaltered potential to recover distinctly separates these subjects from patients with Raynaud's disease.
Evaluation of the Antihypertensive Effect of Lisinopril Compared with Nifedipine in Patients with Mild to Severe Essential Hypertension
Authors: Eber Bernd , Brussee Helmut , Rotman Brigitte , Kramer Rudolf , Klein Werner 
Published: November 2007

For several reasons, increasing numbers of patients with hypertension are treated with angiotensin-converting enzyme inhibitors and calcium channel block ers. In a twenty-four week, double-blind, randomized, parallel study, the anti hypertensive effect of lisinopril (20 to 80 mg qd) and nifedipine (20 to 80 mg bid) were compared in 21 patients. Fourteen patients received lisinopril (mean dose 35 mg), and 7 patients received nifedipine (mean dose 54 mg). By the end of week 12, 8 patients had responded (supine diastolic pressure ≤ 90 mg) to lisinopril and 5 to nifedipine. At the end of the study supine systolic/diastolic blood pressure was reduced from 172/104 to 149/92 mmHg with lisinopril and from 171/102 to 158/94 mmHg with nifedipine. No significant difference be tween the two treatments was detected. Three patients were reported to have at least one clinical adverse experience during the active treatment period, 1 in the lisinopril group and 2 in the nifedipine group. No serious clinical adverse experiences were recorded. In conclusion, lisinopril and nifedipine are both effective in reducing blood pressure in patients with mild to severe hypertension. Lisinopril qd and nifedi pine slow release bid produce similar decreases in blood pressure after twelve weeks of therapy and the safety profiles of the two drugs are similar.