bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors associated with improvement in breathing capacity during exercise in patients with chronic obstructive pulmonary disease
Authors: ONG Kian Chung , WANG Yee Tang
Published: December 2004

Objectives:  The aim of this study was to explore the relationship between resting pulmonary function indices and the ratio of minute ventilation at peak exercise to the maximal voluntary ventilation (V̇Emax/MVV) and to determine whether an improvement in breathing capacity during exercise (i.e. V̇Emax/MVV > 1) is associated with greater exercise capacity in patients with COPD.

Methodology:  The results of pulmonary function tests and incremental, symptom‐limited cardiopulmonary exercise testing in 84 patients with predominantly moderate to severe COPD were reviewed. Multiple linear regression analysis was applied to determine the relationship of V̇Emax/MVV with selected independent variables at rest. Multiple logistic regression was used to determine significant predictors of V̇Emax/MVV ≤ or > 1.

Results:  FEV1/FVC and inspiratory capacity (IC) were the only variables among resting pulmonary function indices that were significant independent determinants of V̇Emax/MVV and the stepwise analysis generated the following equation: V̇Emax/MVV = (−1.05E−02 × FEV1/FVC) + (0.15 × IC) + 1.28; r= 0.701, P < 0.001. Using multiple logistic regression with V̇Emax/MVV ≤ or > 1 as a dependent categorical variable, FEV1/FVC was the only significant predictor among resting pulmonary indices of a V̇Emax/MVV ratio of > 1 (Odds ratio 0.93, 95%CI 0.89, 0.97). There was a significant association between V̇Emax/MVV and peak oxygen uptake (V̇O2max) after adjusting for FEV1 (r = 0.66, P < 0.001). If the categorical variable of V̇Emax/MVV (≤ or > 1) was used instead of a continuous variable, a significant association with V̇O2max remained after adjusting for FEV1 (r = 0.60, P < 0.001).

Conclusions:  Among resting pulmonary function indices, the FEV1/FVC ratio is the best determinant of an improvement in breathing capacity during exercise in COPD patients. After adjusting for FEV1, an improvement in breathing capacity during exercise is associated with significantly higher exercise capacity.
Improvement in health‐related quality of life with fluticasone propionate compared with budesonide or beclomethasone dipropionate in adults with severe asthma
Authors: RUTHERFORD Carolyn , MILLS Rose , GIBSON Peter G. , PRICE Martin J.
Published: December 2004

Objective:  Changes in health‐related quality of life (HRQoL) were evaluated in adults with severe asthma following inhaled corticosteroid treatment with high‐dose beclomethasone dipropionate or budesonide (BDP/BUD) and compared with fluticasone propionate taken at approximately half the dose of BDP/BUD.

Methodology:  HRQoL was assessed as part of an open, multicentre, randomized, parallel‐group study in Australia evaluating the safety and efficacy of switching to fluticasone propionate (FP) 1000–2000 µg/day (n = 67) compared with remaining on BDP/BUD ≥1750 µg/day (n = 66) for 6 months. Patients completed two HRQoL questionnaires, the Asthma Quality of Life Questionnaire (AQLQ) and the Medical Outcomes Study Short Form‐36 (SF‐36), at baseline and at weeks 12 and 24. A change in AQLQ score of ≥0.5 was considered to be clinically meaningful.

Results:  There were significant improvements in HRQoL with FP on four of the eight dimensions on the SF‐36 (i.e. physical functioning, general health, role‐emotional, and mental health), while there were no significant improvements in HRQoL in the BDP/BUD group. Overall, patients in the FP group experienced significantly greater improvement (P < 0.001) in AQLQ scores at weeks 12 and 24 compared with the BDP/BUD group. On the individual domains of the AQLQ, there were significant treatment differences (P < 0.01) in favour of FP in three of the four domains (activity limitations [0.92], symptoms [0.73], and emotional function [1.02]). Mean differences between groups for overall score and these three domains were also clinically meaningful.

Conclusion:  Patients with severe asthma who received FP (at approximately half the dose of BDP/BUD) experienced statistically significant, as well as clinically meaningful, improvements in their HRQoL.
Cardiocirculatory effects of patent ductus arteriosus in extremely low‐birth‐weight infants with respiratory distress syndrome
Authors: Shimada Senji , Kasai Takeo , Hoshi Atsuki , Murata Atsushi , Chida Shoichi
Published: December 2004

Background
: Cardiocirculatory effects of hemodynamically significant patent ductus arteriosus (hsPDA) have not been systematically studied in extremely low‐birth‐weight (ELBW) infants with respiratory distress syndrome (RDS). The objective of the present study was to evaluate the effects of hsPDA on the left ventricular output (LVO) and organ blood flows in ELBW infants with RDS.

Methods
: Extremely low‐birth‐weight infants (birth‐weight <1000 g) treated with surfactant for RDS were studied by serial Doppler flow examinations. Doppler flow variables in 19 infants in whom hsPDA developed (hsPDA group) were compared with those in 19 infants without hsPDA matched for gestational age, birth‐weight, and postnatal age (non‐hsPDA group). All infants in the hsPDA group had pharmacologic closure of ductus arteriosus when hsPDA developed.

Results
: Before pharmacological closure of PDA, the hsPDA group had significantly higher LVO, lower blood flow volume of the abdominal aorta, and lower mean blood flow velocities in the celiac artery, superior mesenteric artery, and renal artery than the non‐hsPDA group. These alterations in the hsPDA group reverted to the levels in the non‐hsPDA group after the closure of PDA and had no deleterious effects on the cardiorespiratory status. No significant differences between the groups were found in mean blood flow velocities of the anterior cerebral artery throughout the study period.

Conclusion
: These results indicate that although LVO is increased, the splanchnic and renal blood flows are decreased when hsPDA develops in ELBW infants with RDS. The effects of these alterations of LVO and organ blood flows on the cardiorespiratory course seem to be minor when early pharmacologic closure of PDA is done.
Endocrinological actions of Unkei‐to, a herbal medicine, and its clinical usefulness in anovulatory and/or infertile women
Authors: Ushiroyama Takahisa
Published: December 2004

Kampo medicine (Chinese herbal medicine) has been reported to be effective in the treatment of pituitary–ovarian dysfunction in young women and in the treatment of undefined symptoms in perimenopausal women. It has been considered that both the diagnosis and treatment of ovulatory failure in adolescent girls or young women are necessary for the sake of future fertile capacity. However, treatment for the above patients is not easy as steroid hormones and strong stimulators of ovulation should not be recommended because of the several side‐effects it causes. Furthermore, young women, especially teenagers, seem to be reluctant to visit gynecology clinics. A number of herbal medicines have been used for many centuries in China and Japan for the treatment of menstrual disorders and infertility. In general, the traditional Chinese herbal prescriptions are rather inexpensive and safe with little side‐effects, and have properties for normalizing biological balances. Unkei‐to is known to stimulate the synthesis and release of gonadotropins in the rat pituitary. In humans, Unkei‐to is known to be effective in various menstrual disorders, abnormal uterine bleeding, and infertility. In the treatment of ovulatory failure, recent dynamic studies have revealed the mechanism by which Unkei‐to stimulates the diencephalon–pituitary–ovarian axis in humans. In this paper, we critically review the clinical data available (to date) in order to assess the efficacy of Unkei‐to in inducing ovulation in several types of ovulatory disturbances. (Reprod Med Biol 2003; 2: 45–61)
Structural macromechanics approach in dynamics of fracture
Authors: PETROV Y. V. , MOROZOV N. F. , SMIRNOV V. I.
Published: December 2004

Discrete features of the dynamics of fracture of solids are analyzed. The problem of modeling of some of the specific effects of brittle fracture in the high loading rate conditions is discussed. An approach based on the system of fixed material constants describing macro‐strength properties of the material is considered. New principles of material testing are analyzed. The corresponding incubation time criterion allows one to manage without the a priori given rate dependences of dynamic strength and fracture toughness. An application of the incubation time criterion to the problem of erosion is considered.
Effect of Biventricular Pacing on Myocardial Glucose Metabolism in Patients with Heart Failure Using Fluoro‐18‐Deoxyglucose Positron Emission Tomography
Authors: OHKUSU YASUO , TAKAHASHI NOBUKAZU , ISHIKAWA TOSHIYUKI , SUMITA SHINICHI , KOBAYASHI TSUKASA , MATSUSHITA KOHEI , YAMAKAWA YOUHEI , UCHINO KAZUAKI , KIMURA KAZUO , INOUE TOMIO , UMEMURA SATOSHI
Published: December 2004

OHKUSU, Y., et al.: Effect of Biventricular Pacing on Myocardial Glucose Metabolism in Patients with Heart Failure Using Fluoro‐18‐Deoxyglucose Positron Emission Tomography.
Biventricular pacing has recently been found beneficial in the treatment of congestive heart failure (CHF). Meanwhile, positron emission tomography (PET) has emerged as a new method to analyze glucose metabolism in the heart. Five patients (mean age

68.8 ± 8.1  years

, 4 men) who received biventricular pacing therapy for

5.8 ± 6.6

weeks for CHF were studied. Myocardial glucose metabolism was evaluated by PET with fluoro‐18‐deoxyglucose (18F‐FDG), and percent uptake (%uptake) of 18F‐FDG was calculated during biventricular pacing and compared with that during 1 hour of conventional RV pacing. Biventricular pacing was associated with a significant decrease in NYHA functional Class from 3.67 ± 0.52 to 2.50 ± 0.55. After 18F‐FDG PET, three of five patients remained clinically stable, and two died during follow‐up. Mean 18F‐FDG %uptake during biventricular pacing was not different than during short‐term RV pacing (

62.1 ± 18.4

vs.

63.6 ± 17.0%

). However, patients who remained clinically stable had a lower value of 18F‐FDG %uptake in the septal region than patients who died (

46.9 ± 5.6

vs

80.3 ± 1.3%, P < 0.01

). One patient whose cardiac function improved significantly also had a small septal region of decreased 18F‐FDG uptake during RV pacing. In conclusion, biventricular pacing therapy was effective in this small group of patients with severe, drug‐resistant CHF. An evaluation of the effects of biventricular pacing on glucose metabolism in the subacute phase may help identify patients with a favorable long‐term response to this therapy. (PACE 2003; 26[Pt. II]:144–147)
Biventricular Pacing via a Persistent Left Superior Vena Cava: Report of Four Cases
Authors: GASPARINI MAURIZIO , MANTICA MASSIMO , GALIMBERTI PAOLA , COLTORTI FERNANDO , SIMONINI STEFANO , CERIOTTI CARLO , GRONDA EDOARDO
Published: December 2004

GASPARINI, M., et al.: Biventricular Pacing via a Persistent Left Superior Vena Cava: Report of Four Cases.
Persistence of left superior vena cava (LSVC) is an uncommon finding during pacemaker implantation, which may be particularly relevant in performing LV transvenous pacing. Rarely, it is further complicated by the presence of atresia of the coronary sinus ostium (CSO). This article reports the authors experience with biventricular pacing (Biv‐P) in this unusual clinical setting. From October 1999 to April 2002, 158 patients underwent biventricular pacing. In four of them (mean age 62.2 years), the presence of a persistent LSVC draining into the coronary sinus (CS) was detected at implantation, associated with atresia of the CSO in two patients. A common characteristic was the angiographic finding of a large CS with few tributaries. The LV leads were successfully positioned in the middle cardiac vein in three patients and in a posterolateral vein in one patient. All vessels were large and their cannulation via downstream CS catheterization required the lead to be manipulated through sharp angles. Mean fluoroscopic exposure and procedural times were not significantly different from the overall Biv‐P population. In all patients, at a mean follow‐up of 11 months, sensing and capture threshold remained stable and a significant decrease in NYHA functional class and increase in LVEF were noted. The direct lead placement in large CS tributaries in the presence of persistent LSVC was feasible and safe. The leads remained stable up to a mean follow‐up of nearly 1 year. (PACE 2003; 26[Pt. II]:192–196)
Bachmann's Bundle Versus Right Atrial Appendage Capture
Authors: BAILIN STEVEN J. , MACHADO CHRISTIAN , NSAH EMMANUEL , WORLEY SETH , KREMERS MARK , BAILEY J. RUSSELL , HILDEBRAND LAURA
Published: December 2004

BAILIN, S.J.,

et al

.: Bachmann's Bundle Versus Right Atrial Appendage Capture.
The tissue in the high intraatrial septum in the region of Bachmann's Bundle (BB) exhibits electrophysiological properties that differ from the right atrial appendage (RAA). As BB pacing emerges as an alternative to RAA pacing, the feasibility of using automatic capture recognition technology in this location should be examined. At implant, active‐fixation leads were consecutively placed in the RAA, then the BB in 18 patients (55.5% men, mean age

77.1 ± 9.1

). There was no significant difference between BB and RAA in the average capture threshold (1.12 vs 1.77 V, P = 0.09), sensing threshold (3.85 vs 3.69 mV, P = 0.84), impedance (508 vs 529 Ohms, P = 0.64), evoked response (1.78 vs 1.67 mV, P = 0.83), and polarization (0.41 vs 0.46 mV, P = 0.84) between. The difference in tissue characteristics was not associated with a different evoked response measured by the ventricular capture recognition algorithm. Based on the analogous evoked response and polarization values, capture recognition technology designed for the atrium will most likely be applicable at both pacing sites. (PACE 2003; 26[Pt. II]:264–267)
Paradoxical Autonomic Modulation of Atrioventricular Nodal Conduction During Heart Rate Turbulence
Authors: WICHTERLE DAN , SAVELIEVA IRINA , MEARA MAGGIE , CAMM A. JOHN , MALIK MAREK
Published: December 2004

WICHTERLE, D., et al.: Paradoxical Autonomic Modulation of Atrioventricular Nodal Conduction During Heart Rate Turbulence.
Heart rate turbulence (HRT) represents a biphasic chronotropic response of sinus rhythm to a single ventricular premature beat (VPB). It consists of early acceleration and late deceleration of heart rate and is predominantly mediated by the autonomic nervous system. The aim of this study was to investigate if autonomic perturbations after a VPB exert a significant effect on AV conduction. Both surface ECG and the high right atrial electrogram were recorded at a sampling frequency of 1000 Hz in 26 patients (24 men, mean age 49 ± 12 years) referred for electrophysiological evaluation. The stimulation protocol consisted of series of single ventricular extrastimuli delivered from the right ventricular apex at decreasing coupling intervals. A biphasic profile of AV intervals after a single VPB was observed. The response of AV conduction to a VPB was approximately 25 times and 15 times weaker in the early and late phase, respectively, than that of R‐R intervals. Thus, AV interval dynamics significantly preceded the change in R‐R intervals, which is in conflict with the near to zero phase of transfer function between R‐R and AV intervals described in previous studies. A significant AV turbulence was observed consisting of early shortening and later prolongation of AV intervals after VPB. Its magnitude was much smaller than that of HRT. Dynamics of AV delay has little impact on the accuracy of HRT assessment from surface ECG. The significant temporal dissociation of R‐R and AV interval dynamics after a VPB remains unexplained. (PACE 2003; 26[Pt. II]:440–443)
Microwave, Irrigated, Pulsed, or Conventional Radiofrequency Energy Source: Which Energy Source for Which Catheter Ablation?
Authors: ERDOGAN ALI , GRUMBRECHT STEPHAN , NEUMANN THOMAS , NEUZNER JOERG , PITSCHNER HEINZ F.
Published: December 2004

ERDOGAN, A., et al.: Microwave, Irrigated, Pulsed, or Conventional Radiofrequency Energy Source: Which Energy Source for Which Catheter Ablation?
The aim of the study was to compare the diameter of endomyocardial lesions induced with the delivery of microwave, cooled, or pulsed energy versus conventional RF energy. In vitro tests were performed in fresh endomyocardial preparations of pig hearts in a 10‐L bath of NaCl 0.9% solution at 37°C and constant 1.5 L/min flow. Ablation 7 Fr catheters with 4‐mm tip electrodes were used, except for the delivery of microwave energy. Energy delivery time was set to 60 s/50 W in all experiments. Cooled energy delivery was performed with a closed irrigation catheter. Pulsed energy delivery was performed using a special controller with a duty‐cycle of 5 ms. Microwave energy was delivered with a 2.5‐GHz generator and 10‐mm antenna. Electrode temperature and impedance were measured simultaneously. After ablation, lesion length, width, and depth were measured with microcalipers, and volume calculated by a formula for ellipsoid bodies. Each energy delivery mode was tested in ten experiments. The deepest lesions were created with cooled energy delivery, and the largest volume by microwave energy delivery. Pulsed RF produced significantly deeper lesions than conventional RF energy delivery. Cooled or pulsed RF energy delivery created deeper transmural lesions than conventional RF. To create linear lesions at anatomically complex sites (isthmus), microwave energy seemed superior by rapidly creating deep and long lesions. (PACE 2003; 26:[Pt. II]:504–506)
Popliteal pterygium syndrome with syngnathia
Authors: Patel Vikram , Theroux Mary C. , Reilly James
Published: December 2004

We report a case of perioperative management of a neonate with popliteal pterygium syndrome complicated by interalveolar syngnathia. Syngnathia were excised in the operating room without a major anaesthetic. We discuss our management of this case, as well as other possible strategies to secure the airway in neonates with syngnathia. We also reviewed the literature regarding airway management in presence of syngnathia in similar situations.
Anaesthetic implications of Costello syndrome
Authors: Katcher Kelly , Bothwell Marcella , Tobias Joseph D.
Published: December 2004

Summary Costello syndrome is a disorder that primarily involves ectodermal tissues and is characterized by mental and growth retardation, distinctive coarse facies, redundant skin (neck, palms and soles), and papillomata (perioral, nasal and anal). Of primary concern to anaesthesiologists are potential airway difficulties related a short neck, macroglossia, hypertrophied tonsillar and supraglottic tissues, laryngeal papillomata and choanal atresia. A significant percentage of patients also have cardiac involvement which may manifest as congenital heart defects, arrhythmias, valvular dysfunction, or hypertrophic cardiomyopathy. Central nervous system involvement includes developmental delay and seizure disorders while endocrine abnormalities have been reported including hypothalamic–pituitary dysfunction resulting in hypopituitarism, hypothyroidism, and hypoadrenalism. The authors present a 2‐year old child with Costello syndrome who required anaesthesia for direct laryngoscopy, rigid bronchoscopy, bilateral pressure equalization tubes and tonsillectomy. The perioperative implications of the syndrome are discussed.
Effects of systemic and epidural morphine on antidiuretic hormone levels in children
Authors: Bozkurt Pervin , Kaya Guner , Yeker Yuksel , Altintas Fatis , Bakan Mefkur , Hacibekiroglu Munire , Kavunoglu Gulsev
Published: December 2004

Background: Although the use of opioids during general anaesthesia suppresses stress response to surgery and pain, the effects on antidiuretic hormone (ADH) are controversial. The aim of this study was to find the effects of morphine with either intravenous infusion or epidural route on ADH and other stress hormones.

Methods: Fifty children aging (1–15 years) undergoing major genito‐urinary or abdominal operations were included in this study. The patients were allocated randomly to two groups receiving either a single dose of epidural morphine 0.1 mg·kg−1 (EP group, n = 25) postinduction or morphine infusion (INF group; n = 25) at 0.02 mg·kg−1·h−1 following 0.05 mg·kg−1 bolus. Blood samples were withdrawn for plasma ADH, osmolality, glucose, cortisol, insulin and morphine level analysis following induction and 1, 5, 12 and 24 h after initial morphine administration.

Results: The two groups were similar in demographic factors, pain scores, sedation scores, and incidence of nausea and vomiting. The amount of morphine received was different between groups and the changes in serum levels of morphine were statistically significant in EP group ( P < 0.05). The changes in cortisol, blood glucose and insulin levels were insignificant in both groups (P > 0.05). The changes of ADH levels were significant at time‐points in both groups, reaching control levels at the 24th hour (P < 0.05).

Conclusion: Despite the effective pain therapy and suppression of cortisol and insulin response to surgical stimulus, the increase in ADH secretion is not effected by systemic or epidural morphine administration.
The use of methohexital during chest tube removal in neonates
Authors: Allegaert K. , Naulaers G. , Debeer A. , Breysem L. , Ferens I. , Vanhole C. , Devlieger H. , Tibboel D.
Published: December 2004

Background : The aim of the study was the evaluation of the effect of methohexital during chest tube removal (CTR) in neonates.

Methods : Evaluation was based on the degree of sedation (grades 1–4) and relaxation (grades 1–4) and trends in vital signs heart rate, mean arterial blood pressure (MAP), oxygen saturation at time points (−10, −5, −3, −1, 0, 1, 3, 5, and 10 min) before and after administration of methohexital. A multidimensional pain scale [Leuven Neonatal Pain Scale (LNPS)] was used to evaluate pain expression. Effective sedation and relaxation (grade >2) would enable the physician to perform CTR without difficulties. Paired Wilcoxon was used to compare vital signs and pain expression before and after the procedure.

Results : Twenty‐two procedures in 22 infants were recorded. Eleven infants were ventilated and 21 infants were having intravenous analgesics during CTR. Birth weight was 2645 g (range 1235–4500 g). Postnatal age was 6 days (range 1–80 days). Methohexital had no effect on ventilatory weaning, MAP or oxygen saturation. Heart rate increased from 144 (49) to 162 (43) (P = 0.012) b·min−1. Sedation and relaxation were effective (>grade 2) and lasted for <5 min. No major side effects were documented. Adequate analgesia by LNPS was more difficult to evaluate as clinical pain evaluation was not feasible during full muscular relaxation.

Conclusions : Administration of methohexital for CTR resulted in adequate sedation and relaxation without major side effects in neonates. This approach should be compared with other strategies.
Is licofelone, a dual inhibitor of cyclo‐oxygenase and 5‐lipoxygenase, a promising alternative in anti‐inflammatory therapy?
Authors: Bannwarth Bernard
Published: December 2004

As prostaglandins and leukotrienes are critical in inflammation, dual cyclo‐oxygenase and 5‐lipoxygenase enzymes inhibitors, especially licofelone, are being developed by pharmaceutical companies. Experimental data indicate that licofelone shares the antipyretic, analgesic, anti‐inflammatory and anti‐platelet activities of conventional nonsteroidal anti‐inflammatory drugs (NSAIDs), and exhibits anti‐allergic properties. Although licofelone may lead to similar adverse effects on the kidney than available NSAIDs, it appeared to induce less gastrointestinal damaging effects than nonselective NSAIDs in animals. Unfortunately, preliminary clinical studies provided less impressive data with respect to efficacy. Finally, the experimental promise of licofelone as a safe and potent anti‐inflammatory and analgesic agent remains to be proved in humans.
Influence of simulated weightlessness on the pharmacokinetics of acetaminophen administered by the oral route: a study in the rat
Authors: Gandia Peggy , Saivin Sylvie , Lavit Michel , Houin Georges
Published: December 2004

During space flights, the human body is submitted to weightlessness which induces physiological variations that could modify drug disposition during space missions. Since space experiments are infrequent and difficult to perform, in order to evaluate pharmacokinetic modifications, simulation experiments of weightlessness have to be carried out on earth, using animal‐models such as the Morey‐Holton model. In this model, rats are suspended by the tail with their front paws on the ground. We studied the effects of simulated weightlessness on drug absorption and on gastric emptying, using acetaminophen as a probe. Three periods of suspension (1, 2 and 5 days) were compared with two control groups (free and attached rats). The attached group was used to evaluate a possible ‘stress effect’ caused by the suspension device. Each group was composed of 36 rats (12 sampling times and three rats per time). An oral dose of acetaminophen (100 mg/kg) was administered and blood samples were collected before and up to 12 h after administration. Plasma assays were performed using an high‐performance liquid chromatography method with UV detection. The calculated population pharmacokinetic parameters were Ka, Kel (first order absorption and elimination constants) and Vd/F (apparent volume of distribution). The statistical interpretation of the population pharmacokinetic parameters indicated that 2 days of suspension significantly decreased the Vd/F by 83% and the Ka by 125%. The increase in the Ka was probably because of an increased acceleration of the gastric emptying and/or to a decrease in the total peripheral resistance which increased intestinal blood flow.
Benign Neonatal Hemangiomatosis
Authors: Leung Alexander K. C. , Rafaat Massoud
Published: December 2004

Abstract: An infant with benign neonatal hemangiomatosis is described. Examination for internal hemangiomas was negative. The patient had complete resolution of the lesions by 2 years of age.
Presence of Vascular Anomalies with Congenital Hemihypertrophy and Wilms Tumor: An Evidence‐Based Evaluation
Authors: Kundu Roopal V. , Frieden Ilona J.
Published: December 2004

Abstract:Congenital hemihypertrophy is an uncommon condition of unknown etiology characterized by unilateral overgrowth of part or all of one side of the body. Hemihypertrophy is known to be associated with certain childhood tumors, most notably Wilms tumor (or nephroblastoma), and for this reason infants with hemihypertrophy are often followed with serial abdominal ultrasounds. Klippel–Trénaunay syndrome (KTS) is the triad of port‐wine stain, venous varicosities, and soft tissue and/or bony hypertrophy. Children with KTS typically have localized rather than generalized hemihypertrophy, but occasionally the hypertrophy is more extensive than the vascular anomaly itself. Information is lacking about whether hemihypertrophy in this setting can also be a risk factor for Wilms tumor. We systematically reviewed the medical literature to determine whether well‐documented cases of Wilms tumor in the setting of both hemihypertrophy and vascular anomalies have been described, and if found, whether the association was sufficiently frequent that routine screening for Wilms tumor in this setting should be recommended. A review of case reports and case series in the pediatric population was undertaken using specific inclusion and exclusion criteria. We found 4 of 58 subjects with hemihypertrophy and Wilms tumor had a reported vascular anomaly, but in only one case was a clear‐cut diagnosis of KTS confirmed. The relationship of the other three vascular anomalies reported was of uncertain significance. In conclusion, our review suggests that the risk of Wilms tumor in the setting of localized soft‐tissue hypertrophy in conjunction with a vascular malformation is quite low. More extensive hemihypertrophy extending to body sites remote from the vascular malformation itself could have a higher risk of Wilms tumor, although the magnitude of this risk is uncertain. Our findings suggest that routine serial abdominal ultrasounds in patients with vascular malformations in association with localized soft‐tissue hypertrophy are unwarranted.
Epidemiology of Childhood Vitiligo: A Study of 625 Patients from North India
Authors: Handa Sanjeev , Dogra Sunil
Published: December 2004

Abstract:To study the clinical and epidemiologic profile of childhood vitiligo, we retrospectively analyzed the data of children with vitiligo attending the pigmentary clinic of our center. Of the 625 children seen over 10 years, 357 (57.1%) were girls and 268 (42.9%) were boys. As compared to adult patients with vitiligo, this sex difference was found to be statistically significant (p < 0.001). The mean age of onset of the disease was 6.2 years. Vitiligo vulgaris (generalized vitiligo) was the most common type, followed by focal, segmental, acrofacial, mucosal, and universal, in that order. The most frequent site of onset was the head and neck, followed by the lower limbs, trunk, upper limbs, and mucosae. Leukotrichia was present in 77 patients (12.3%), while Koebner phenomenon was observed in 71 patients (11.3%). Halo nevi were observed in 29 patients (4.4%). Seventy‐six patients (12.2%) had a family history of vitiligo. Eight patients (1.3%) had an associated autoimmune disease. These associated disorders were alopecia areata in two patients, and diabetes mellitus, thyroid disease, Addison disease, polyglandular syndrome, and pemphigus vulgaris in one patient each.
Modulation of trigeminal reflex excitability in migraine: effects of attention and habituation on the blink reflex.
Authors: De Tommaso M , Murasecco D , Libro G , Guido M , Sciruicchio V , Specchio LM , Gallai V , Puca F
Published: December 2004

Int J Psychophysiol. 2002 Jun;44(3):239‐249

The modulation of trigeminal reflex excitability in migraine patients was evaluated during the asymptomatic phase by studying the effects of attention, habituation and preconditioning stimulus on the R2 and R3 components of the blink reflex (BR). Fifty patients suffering from migraine without aura, 20 affected by migraine with aura and 35 sex‐ and age‐matched controls were selected. In subgroups of migraine with‐aura and without‐aura patients, and normal controls, the blink reflex was elicited during different cognitive situations: (a) spontaneous mental activity; (b) stimulus anticipation; (c) recognition of target numbers. In the remaining subjects, R2 and R3 habituation was evaluated by repetitive stimulation at 1, 5, 10, 15, 20, 25 and 30 s intervals. The R2 and R3 recovery curves were also computed. A reduced R3 threshold with a normal pain threshold was found in migraine with‐aura and without‐aura patients; the R3 component was not significantly correlated with the pain thresholds in patients and controls. The R2 and R3 components were less influenced by the warning of the stimulus in migraine without‐aura and migraine with‐aura patients, in comparison with the control group. A slight increase of both R2 and R3 recovery after preconditioning stimulus was also observed in migraine patients, probably caused by a phenomenon of trigeminal hyperexcitability persisting after the last attack. The abnormal BR modulation by alerting expresses in migraine a dysfunction of adaptation capacity to environmental conditions, probably predisposing to migraine.

Comment: Further physiologic and functional evidence for the interictal hyperexcitability of neurons in patients with migraine, in this case trigeminal neurons involved in the blink reflex. SJT
Instability of Flow between Parallel Planes with a Coplanar Magnetic Field
Authors: Wooler P. T.
Published: December 2004

The equations determining the growth of three-dimensional disturbances in the presence of a coplanar magnetic field, which is not parallel to the flow, are shown to be similar to those which determine the growth of two-dimensional disturbances when the field is parallel to the flow. When the field is not parallel to the flow the critical Reynolds number for the flow is shown to be finite for disturbances propagated in a certain direction. A consequence of this result is that the analog of Squire's theorem does not hold, in general, when the magnetic field is not in the flow direction.
Apparent Viscosity of a Charged Fluid
Authors: Stuetzer Otmar M.
Published: December 2004

Charges in a liquid or gas, under the influence of a self-created or applied field, increase the viscous losses. The general equations for a macroscopic electrohydrodynamic treatment of this phenomenon are given. Steady-state channel flow and a simple dynamic situation are theoretically investigated and compared with the magnetohydrodynamic cases. Some experiments are described.
High-β Injection into a Magnetic Mirror Field
Authors: Scott F. R. , Eldridge O. C.
Published: December 2004

Axial injection of a high-density helium plasma into a magnetic mirror has been experimentally studied. Observations of the plasma-field interaction were made with magnetic probes, electrostatic probes, piezoelectric probes, and an optical monochromator which analyzed emission-line profiles. In the central plane of the mirror a density of 2 ± 1 × 1015 ions/cm3 and a maximum ion temperature of 10 ev are indicated. In the upstream region ion temperatures of 35 ± 5 ev were recorded. Diamagnetic signals show that the high-β plasma ``stagnates'' near the upstream throat of the mirror. Also, the derived plasma pressure measured on axis decreases exponentially downstream. Piezoelectric-probe measurements show large axial-momentum transfer rates in the downstream region of the mirror, where no diamagnetic signals are observed. The data are compared with a fluid model of a plasma which describes the injection, ``stagnation,'' and effusion along field lines. This experiment indicates that the axial injection of a collision-dominate, high-β plasma into a static mirror field is not efficient for producing and confining a high-temperature plasma.
Lagrangean Density for an Inviscid, Perfect, Compressible Plasma
Authors: Katz Sylvan
Published: December 2004

A Lagrangean density formulated in the Lagrangean coordinate system is proposed for a one-fluid, inviscid, perfect, compressible plasma undergoing isentropic motion in an electromagnetic field. Variations of the electromagnetic field potentials yield Maxwell's equations while variations in the particle paths result in the equations of fluid motion.
Second Virial Coefficient for the Morse Potential
Authors: Konowalow Daniel D. , Taylor Marion H. , Hirschfelder J. O.
Published: December 2004

Tables and algorithms are given for the classical second virial coefficient and its first two temperature derivatives for gases obeying a Morse potential φ(r) = ε (x2 − 2x), where x = exp [− (c/σ) (r − rm)]. The calculations cover the temperature range 0.3 ≤ kT/ε ≤ 400.
Interaction between a Radio Wave and a Plasma
Authors: Koga Toyoki
Published: December 2004

The interaction between a radio wave and a plasma is studied based on the Boltzmann equation for electrons. Collisions between electrons and heavy particles and the electric field caused by the group displacement of electrons are taken into account. The relation between the current density and the oscillating electric field is obtained. The solution is exact so far as the proposed Boltzmann equation for electrons is concerned. According to the result, the propagation of the radio wave in the plasma is investigated. As the electric field caused by the group displacement of electrons becomes negligibly weak, the results approach those obtained by Margenau.
Low-Density Plasma Flow at a Magnetic Barrier
Authors: Gilleo M. A.
Published: December 2004

The encounter of a low-density stream of plasma with a barrier in an otherwise uniform axial magnetic field is treated theoretically on the basis of particle dynamics. Conditions are considered for which the magnetic moments which result from the transverse velocities of the particles are adiabatically invariant within the barrier region. At the barrier there is an increase of magnetic field caused by external currents and increase in electric potential φ caused by charge separation in the plasma. Within the barrier the electric potential brings about an exchange of energy eφ between ions which carry the kinetic energy of the stream and electrons so that both may penetrate in equal number. The penetration of the barrier, the force on it, and the change of electric potential in it are given in terms of the ratio of barrier to guiding-field, stream velocity, and the temperatures of the ions and electrons. A comparison is made with results which have been obtained for an encounter in which the barrier rises so rapidly that the moment of the ions is not adiabatically invariant and for which the Rosenbluth-Garwin sheath model has been employed. This model is appropriate to cases in which a rapidly varying current flows on the surface of the plasma (skin effect) as in the pinch effect. Much greater penetration takes place with the slowly varying magnetic field which may be encountered when the field is produced by current-carrying conductors external to the plasma.
Relativistic Effects on Plasma Stability
Authors: Noerdlinger Peter D.
Published: December 2004

For an anisotropic uniform plasma in a steady magnetic field, the nonrelativistic theory and Lerche's treatment of highly relativistic plasmas both give instability whenever the pressure p⊥ perpendicular to the magnetic field exceeds p∥, the pressure along the field. Here it is shown that the instability persists in weakly relativistic plasmas, in contrast to the implication by Sudan that it vanishes in certain cases. The firehose instability is also investigated for the weakly relativistic plasma; it is slightly stabilized by relativistic effects.
Steady, Oblique, Nonlinear Waves in a Warm Collision-Free Plasma
Authors: Kever H. , Morikawa G. K.
Published: December 2004

The speed and structure of steady nonlinear waves, moving with uniform velocity in an oblique direction across a magnetic field in a collision-free plasma with temperature, are obtained. This is a self-consistent formulation in which the plasma motion is governed by the Vlasov equations for ions and electrons coupled to the Poisson-Maxwell equations. This problem can be solved in the limiting case of small-amplitude nonlinear waves if the same scaling laws are assumed to hold for the warm plasma as those for a cold plasma. Both compression and rarefaction waves are possible depending on the obliqueness angle and plasma temperature. The critical transition angle increases rapidly with increasing ion temperature but is practically unaffected by increasing electron temperature alone.
Transverse Waves in a Relativistic Plasma
Authors: Lerche I.
Published: December 2004

Linearized equations are set up to describe transverse waves in a relativistic plasma embedded in a magnetic field and in the presence of a nonrelativistic plasma. The waves are taken to propagate at right angles to the unperturbed field. Unstable waves are found to exist when the momentum distribution is taken to be of the cosmic ray type, but anisotropic. The instability exists only when relativistic particles are present and is a consequence of the mass of a fast particle being different from its rest mass. The maximum amplification rate is found for this case and is illustrated numerically by assuming physical values appropriate to the case of galactic cosmic ray electrons. It is shown that any anisotropy is rapidly destroyed and for cosmic ray electrons which are more than about a million years old isotropy is to be expected.
Hamilton's Principle for Electromagnetic Fluids
Authors: Penfield Paul , Haus Hermann A.
Published: December 2004

Hamilton's principle is used to derive the force equation for both nonrelativistic and relativistic flow of a compressible, inviscid fluid with polarization and magnetization. The resulting expression is used to settle the long-standing controversy concerning the ``electromagnetic momentum.'' The derivation is based on the formulation of Hamilton's principle for ordinary fluids in a companion paper.
Reduced Plasma Diffusion in Positive Gradient Magnetic Field Configurations
Authors: Schwirzke Fred
Published: December 2004

The effective electron and ion diffusion coefficients have been measured in magnetic field configurations with positive, zero, and negative gradients of the magnetic induction Bz across the field. The radial density profiles are approximately the same for a mirror configuration ∂Bz/∂r < 0 and a uniform field ∂Bz/∂r = 0. The measured electron diffusion coefficient is by orders of magnitude larger than the collisional one and shows the 1/B dependence of the Bohm-type diffusion process, D⊥−=C kTe/B. The factor C has been determined to C ∼ 10−2. The noise level diminishes and the density profiles become steeper with increasing positive gradients, ∂Bz/∂r > 0, thus showing reduced plasma diffusion. A sharp drop of the electron saturation current to the probe indicates that the anomalous diffusion of the electrons is strongly reduced in certain regions where the radial electric field is weak. The stabilizing effect of an average minimum-B field has been confirmed experimentally.
Initial and Boundary Value Problems in Dissipative Gas Dynamics
Authors: Sirovich Lawrence
Published: December 2004

The discontinuous forms of the full Navier-Stokes equations are derived. A general method of solving linearized initial and boundary value problems is discussed. The following specific examples are solved: initial value problem in an unbounded domain, shock reflection from an insulating wall, shock evolution in a finite shock tube with insulating walls, and reflection of a sound wave from an isothermal wall. In all cases the dissipative parameters and the gas law are left arbitrary.
Stability of a Non-Newtonian Liquid Film Flowing down an Inclined Plane
Authors: Lin S. P.
Published: December 2004

The stability of a layer of a triply nonlinear liquid flowing down an inclined plane is investigated. It is found that the flow is always stable with respect to surface wave formation, if the liquid is predominantly non-Newtonian. However, it is predicted that the instability of the flow is due to shear waves. The reduction of an angle of inclination of the plane and the second viscosity are all shown to be stabilizing factors.
Approximate Analysis of Linearized Inviscid Relaxing Gas Flow
Authors: Sussman M. B. , Baron J. R.
Published: December 2004

Approximate analytical solutions to the third-order, linear partial differential equations governing small disturbances from a uniform state in a relaxing gas are obtained. Such solutions are of interest for providing a qualitative understanding of nonequilibrium flow over thin airfoils and projectiles. Most previous investigations have, due to the complexity of the solution for even this linear problem, presented restricted results valid primarily at the flow boundaries. In contrast, the emphasis is now to provide simplified approximate expressions useful to examine properties at any point in the flow. The particular problem examined is the motion of an infinite mass of gas due to a given planar, cylindrical, or spherical piston motion. The approximation scheme used to simplify the governing equation involves the assumption that the frozen and equilibrium sound speeds are nearly equal, a condition frequently met in practice. The perturbation scheme is found to be singular due to the assumed infinite domain of the gas. The formalism of the method of matched asymptotic expansions is utilized to obtain uniformly valid solutions. Comparison of some of the approximate results is made with exact solutions determined numerically.
Heat Exchange Torques in Superfluids
Authors: Penney R.
Published: December 2004

It is shown that the two-fluid model of helium II leads to the existence of heat exchange torques on nonuniformly heated bodies immersed in flowing helium. The torque on a long cylinder is calculated and shown to be of a magnitude which should be readily observable.
Nonthermal Ionization Caused by Aerodynamic Discontinuities in Charged Aerosol Jets
Authors: Barreto E. , Martinot Katherine
Published: December 2004

Significant space-charge accumulations caused by thermodynamic changes are produced whenever an electrical corona discharge of the streamer type is maintained in a region of rapid and sustained mass density variation. The experimential investigation uses a highly charged supersonic aerosol jet (0.03 C/m3) at temperatures below 300°K and pressures below 3 atm. The aerosol emerges from an underexpanded nozzle producing a characteristic series of expansion and compression regions. The charge density of the aerosol is sufficiently high so that electrical breakdown is induced at a grounded needle placed near or within the jet. It is shown that the ionization produced within the supersonic region, where rapid mass density changes occur, liberates charge in excess of the charge carried by the aerosol and that the current to the induced corona needle reproduces density variations in the underexpanded jet. A model is presented whereby changes in electrical conductivity, produced by the streamers propagating through the jet, result in space charge accumulations. Computation shows that the charge accumulation on shocks and compression and expansion waves is of sufficient magnitude to be responsible for the excess ionization and the visual appearance of the corona discharge.
Plasma Kinetic Theory of Transverse Diffusion
Authors: Haggerty M. J.
Published: December 2004

The kinetic theory of Prigogine and Balescu is applied to the diffusion of a plasma column across a uniform magnetic field. The problem of deriving the kinetic equation for the single-particle distribution function is reduced to that of solving a linear integral equation with a complicated kernel. No restriction is made on the amplitude or length scale of the inhomogeneity across the magnetic field. Although a multicomponent plasma is considered, the calculation ignores macroscopic electric fields. An unusual linearization of the Vlasov equation is also examined. It yields essentially the same linear integral equation, where the kernal represents a generalized electric susceptibility. The problem of finding the unstable modes of oscillation is the eigenvalue problem for the corresponding homogeneous integral equation. If the collective terms are replaced by appropriate cutoffs in the integrations, the kinetic theory becomes relatively simple. In particular, a single kinetic equation describes the collisional transverse diffusion. For a gyrotropic plasma with slab geometry, this kinetic equation reduces to one previously obtained by Eleonskiǐ, Zyryanov, and Silin by a different method; an H-theorem has been established, and some nonequilibrium stationary distributions have been found.
Nonlinear Limit of a Drift Instability Related to Auroral Bombardment
Authors: Krall Nicholas A.
Published: December 2004

The nonlinear development of the low-frequency transverse-drift instability is calculated. Although quasi-linear theory might be expected to be valid for such a mode, wave scattering is required to saturate the mode spectrum. The effect of the fully developed instability is a coordinate displacement, and a shift in v̄z. If applied to the radiation belts, this instability would predict auroral bombardment localized in radius, occurring in the lower density large-gradient regions of the particle distribution.
Velocity of a Bubble Rising in Liquid along the Axis of a Circular Tube
Authors: Lin S. P.
Published: December 2004

The velocity of a bubble rising in liquid along the axis of a circular tube was obtained by Collins. The same problem is treated here both experimentally and analytically by use of a different model which yields a better approximation for the case of small bubble to tube diameter ratios.