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W Rosenfeld

Publications and source records attributed to W Rosenfeld.

At least 19 recordsLinked to original sources
PubMed2000

Brain perfusion monitoring with frequency-domain and continuous-wave near-infrared spectroscopy: a cross-correlation study in newborn piglets.

The newborn piglet brain model was used to correlate continuous-wave (CW) and frequency-domain (FD) near-infrared spectroscopy. Six ventilated and instrumented newborn piglets were subjected to a series of manipulations in blood oxygenation with the effects on brain perfusion known to be associated with brain hypoxia-ischaemia. An excellent agreement between the CW and FD was demonstrated. This agreement improved when the scattering properties (determined by the FD device) were employed to calculate the differential pathlength factor, an important step in CW data processing.

Animals↗
PubMed2000

Alternating antipyretics: is this an alternative?

OBJECTIVES: To identify current fever management strategies and their basis, and to assess the frequency of alternating acetaminophen and ibuprofen. BACKGROUND: Practicing pediatricians confront the dilemma of elevated temperature and the anxiety this creates for parents. An informal survey of pediatricians revealed a variety of management strategies, including alternating acetaminophen and ibuprofen. There are no scientific data regarding alternating these 2 products. Design. During professional meetings, pediatricians voluntarily filled out a 15-item questionnaire. RESULTS: One hundred sixty-one completed surveys were reviewed. Respondents were mostly general pediatricians (67.7%), with >/=20 years in practice (55.9%). Most respondents chose a temperature of 101(o)F to start antipyretic treatment (61.9%). A small percentage used discomfort alone as the indication (13%). The antipyretic of choice was temperature-dependent in 50% of respondents; 57% used ibuprofen for temperature >/=102 degrees F. Fifty percent of respondents advised parents to alternate acetaminophen and ibuprofen. The method of alternation varied. The most common answers given for choosing a particular antipyretic regime were recommendations of the American Academy of Pediatrics (29%) and opinions of colleagues and mentors (25%). Physicians with <5 years of practice were significantly more likely to alternate antipyretics (69.7%). CONCLUSION: Acetaminophen and ibuprofen are commonly being used in an alternating manner for management of fever. There is presently no scientific evidence that this combination is safe or achieves faster antipyresis than either agent alone. There is evidence that the improper use of these agents may cause harm. Despite 29% of participants citing American Academy of Pediatrics recommendations as the basis for fever management, no such policy or recommendations exist. The observation that this practice is more common in younger practitioners may reflect their continued anxiety about fever (fever phobia). Until properly controlled studies have assessed the risk of combining these 2 products, practitioners should proceed with caution.

Acetaminophen↗
PubMed1999

Non-invasive optical monitoring of the newborn piglet brain using continuous-wave and frequency-domain spectroscopy.

We have used continuous-wave (CW) and frequency-domain spectroscopy to investigate the optical properties of the newborn piglet brain in vivo and non-invasively. Three anaesthetized, intubated, ventilated and instrumented newborn piglets were placed into a stereotaxic instrument for optimal experimental stability, reproducible probe-to-scalp optical contact and 3D adjustment of the optical probe. By measuring the absolute values of the brain absorption and reduced scattering coefficients at two wavelengths (758 and 830 nm), frequency-domain spectroscopy provided absolute readings (in contrast to the relative readings of CW spectroscopy) of cerebral haemoglobin concentration and saturation during experimentally induced perturbations in cerebral haemodynamics and oxygenation. Such perturbations included a modulation of the inspired oxygen concentration, transient brain asphyxia, carotid artery occlusion and terminal brain asphyxia. The baseline cerebral haemoglobin saturation and concentration, measured with frequency-domain spectroscopy, were about 60% and 42 microM respectively. The cerebral saturation values ranged from a minimum of 17% (during transient brain asphyxia) to a maximum of 80% (during recovery from transient brain asphyxia). To analyse the CW optical data, we have (a) derived a mathematical relationship between the cerebral optical properties and the differential pathlength factor and (b) introduced a method based on the spatial dependence of the detected intensity (dc slope method). The analysis of the cerebral optical signals associated with the arterial pulse and with respiration demonstrates that motion artefacts can significantly affect the intensity recorded from a single optode pair. Motion artefacts can be strongly reduced by combining data from multiple optodes to provide relative readings in the dc slope method. We also report significant biphasic changes (initial decrease and successive increase) in the reduced scattering coefficient measured in the brain after the piglet had been sacrificed.

Animals↗
PubMed1999

Adding lamotrigine to valproate: incidence of rash and other adverse effects. Postmarketing Antiepileptic Drug Survey (PADS) Group.

PURPOSE: Valproate (VPA) triples the half-life of lamotrigine (LTG), and combined use may be difficult. The adverse effect (AE) profile of this combination needs clarification. METHODS: We prospectively recorded our experience in adding LTG to VPA-containing regimens in 108 patients. Data collected included medications, seizure types and syndromes, and AEs. Patients were followed up to 27 months, until a stable dose was reached, or until LTG was discontinued. Patient management was not altered by this study. There were 60 patients with partial-onset seizures, 30 with generalized onset, and 12 with the Lennox-Gastaut syndrome. In 37, LTG was added to VPA monotherapy, and in 71, to VPA and other drugs. The median starting dose of LTG in our adult patients was 20.8 mg/day. RESULTS: LTG was added successfully in 86 (80%) patients. It was discontinued in 22 (20%): seven because of rash, seven for other AEs, and nine for other reasons. Rash occurred in 14 (13%) but caused discontinuation of LTG in only seven. We found a rash rate of 14.2% and a discontinuation rate because of rash of 8.7% among 310 patients in whom LTG was added to drug regimens not including VPA. Other AEs included fatigue (12%), gastrointestinal (GI) symptoms (9%), dizziness, headache, and insomnia (3% each). Serious AEs were hallucinations (two patients), hepatic enzyme elevations (two patients), irritability (one patient), and low white blood cell count (one patient). Whether LTG was added to VPA monotherapy or polytherapy made no difference in overall AE rate. CONCLUSIONS: LTG can be added to VPA with an acceptable incidence of side effects. LTG-induced rashes are no more common with VPA than with other drugs when LTG is added at very low initial dosages. Rashes are potentially serious and should be evaluated promptly.

Adolescent↗
PubMed1999

Real-time optical imaging of experimental brain ischemia and hemorrhage in neonatal piglets.

Our objective was to study the development of experimental brain ischemia and hemorrhage by real-time optical imaging. Optical imaging is based on the ability of near infrared light to non-invasively penetrate through the intact scalp and skull and measure brain concentrations of oxy- and deoxyhemoglobin, dominant brain absorbers. Optical imaging was performed in 7 anesthetized, instrumented, and ventilated newborn piglets subjected to the injection of 0.3 cc of saline followed by 2 cc of blood into the left frontal subcortical brain region via a needle inserted through the skull with stereotactic guidance. The image-acquisition rate of 5.26 images per sec allowed for real-time imaging. The detection threshold of the imager at the estimated depth of 1-1.5 cm was approximately 70 microL for saline and approximately 40 microL for blood. The imager readily detected five subcortical hematomas and two large bilateral subarachnoid hemorrhages. The imager detected a global decrease in brain absorption associated with the volume-injection-related increase in intracranial pressure in the surrounding ipsilateral and contralateral brain. Any decrease in brain absorption is an equivalent to brain ischemia. This study demonstrates the capability of optical imaging in detecting brain ischemia and hemorrhage in real-time with high temporal and spatial resolution.

Animals↗
PubMed1997

Gabapentin monotherapy: I. An 8-day, double-blind, dose-controlled, multicenter study in hospitalized patients with refractory complex partial or secondarily generalized seizures. The US Gabapentin Study Group 88/89.

We evaluated the efficacy and safety of gabapentin administered as monotherapy in an 8-day, randomized, double-blind, dose-controlled, parallel-group, multicenter study comparing dosages of 300 and 3,600 mg/d gabapentin in 82 hospitalized patients whose antiepileptic medications had been discontinued for seizure monitoring. Seizures under study were complex partial seizures with or without secondary generalization. Patients exited the study if they experienced a protocol-defined exit event indicating lack of efficacy. Time to exit was significantly longer (p = 0.0001) and completion rate was significantly higher (53% versus 17%; p = 0.002) for patients receiving 3,600 mg/d gabapentin. Gabapentin was well tolerated by patients in both dosage groups, and no patients exited the study due to adverse events, despite rapid initiation of full dose within 24 hours. These results demonstrate that gabapentin has anticonvulsant activity and is well tolerated when administered as monotherapy in patients with refractory partial seizures.

Acetates↗
PubMed1996

Parents' evaluations of wheezing in their children with asthma.

OBJECTIVE: Wheezing is a widely used physical sign of asthma that physicians assess in evaluation of their asthmatic patients. It may be possible to teach the parents to recognize it and to assess its severity so as to help them make better informed judgment in monitoring their children with asthma. STUDY DESIGN: Parents were taught to recognize wheezing by placing their ear over the chest and in front of the open mouth of their child. One session lasting a few minutes was sufficient for teaching. Subsequently, the parent and a physician evaluated the child independently for the presence and the severity of wheezing categorized as easily, barely, and none detected, and results were compared. Severity of wheezing was also compared with peak expiratory flow rate (PEFR) whenever possible. RESULTS: Six hundred thirty-six observations were made in 89 parent-child pairs. Wheezing was detected by the physician in 64% of examinations and by the parents in 56% (p < 0.001 by chi 2). When the physician heard the wheezing easily on 240 occasions, the parents also heard it in 99%. When the physician heard the wheezing barely on 170 occasions, the parents heard it only on 68% of the time. Mean PEFR was 55% predicted when the parents heard the wheezing easily, 75% when heard barely, and 93% when not heard (the difference is significant, p < 0.001 by analysis of variance). CONCLUSIONS: Parents can be taught to detect wheezing in their child with considerable accuracy when it is easily detectable to a physician. Such skills should be helpful to the parents in monitoring their child with asthma and in deciding when to increase medications and when to seek emergency care.

Adolescent↗
PubMed1992

Oxygen affects human endothelial cell proliferation by inactivation of fibroblast growth factors.

The fibroblast growth factors (FGF), including endothelial cell growth factor (ECGF)/acidic FGF and basic FGF, are important modulators of endothelial cell replication in vitro and in vivo. Premature infants and adults with lung injuries are often treated with high levels of inspired O2, which can be necessary for survival but potentially injurious to developing lungs and in tissue repair following injury. Human umbilical artery and vein endothelial cells were grown in ECGF- or FGF-supplemented Medium 199 and exposed to ambient levels of O2 from 10 to 95%. Endothelial cell growth, measured by [3H]thymidine incorporation, was inhibited by increasing levels of O2 and ceased above 50% O2. Vein endothelial cells could recover from up to 24 h of hyperoxic exposure when given fresh medium, but not after 48 h. Artery-derived cells were more sensitive to O2 than were vein-derived cells. Complete medium without endothelial cells, preincubated 24 h in 95% O2, lost its ability to support cell growth under normoxic conditions. Exposing individual medium components to high O2 demonstrated that purified natural ECGF and recombinant acidic or basic FGF were all inactivated by O2. Human recombinant superoxide dismutase prevented FGF inactivation. O2 inactivation of essential growth factors could thus have major consequences for lung development or repair of injured capillaries in infants or adults inspiring high levels of O2.

Cell Division↗
PubMed1991

Impact of pediatricians' attire on children and parents.

To evaluate perceptions of a pediatrician's attire, 50 children and parents in an outpatient facility were shown five photographs of a female or a male physician dressed differently (formal to informal). A list of positive and negative attributes was presented to the parents and children who were to match each picture to the attributes. Parents had a strong positive preference for the formally dressed female (short white coat and skirt), and the formally dressed male (short white coat and tie). More than 50% of the parents least preferred the most informal attire. Children had no clear preferences for males and preferred the female in the blouse and skirt. Children assigned negative attributes to informal attire but not to the same degree as did their parents. This study demonstrates that parents have stronger preferences than do their children. Although children had no strong positive preferences, they may feel negatively about informal attire.

Adolescent↗
PubMed1990

Clavicular fractures in neonates.

We evaluated the wide variation in the reported incidence of fractured clavicles (0.2% to 3.5%) in newborns by screening 626 consecutive infants delivered vaginally for fractures. One of us (P.R.J.) evaluated all infants, twice during the initial hospital stay and 2 weeks later. Eighteen fractured clavicles were identified for a frequency of 2.9% (18/626). One fracture was discovered on the first hospital examination, 10 on discharge, and 7 at follow-up. Only 2 patients had symptoms usually associated with fractured clavicles. The most reliable clinical sign for in-hospital diagnosis was difficulty in feeling the margins of the affected clavicle when compared with the normal clavicle. The mean birth weight of the infants was 3604 g (range, 3000 to 4930 g), and no obstetric complications occurred. The reported frequency of fractures diagnosed clinically during hospitalization significantly underestimates their occurrence. Most newborn infants with fractures have no symptoms and minimal physical findings during the first days of life, making repeated examination necessary.

Clavicle↗
PubMed1990

A new device for phototherapy treatment of jaundiced infants.

A new device for phototherapy consisting of a fiberoptic panel attached to an illuminator was compared with traditional phototherapy (4 special blue and 4 daylight bulbs). The panel surrounds the trunk eliminating eye patching and allowing more time for maternal-infant interaction. Forty-six jaundiced term neonates were studied. Two groups, nonhemolytic (n = 26) and hemolytic (ABO) (n = 20) jaundice, received fiberoptic or traditional phototherapy. In both groups, fiberoptic and control patients had similar weights, gestational ages, bilirubin levels and ages at entry. Post-therapy weights and duration of therapy were also similar. In the nonhemolytic fiberoptic group, there was a trend toward greater decreases in mean bilirubin levels at 12, 24, 36, and 60 hours with significant reduction at 48 hours of therapy (-2.8 vs -.5 mg/dL; P = .04). In the hemolytic group, bilirubin fell continuously in the fiberoptic group and after 36 hours in the traditional group. At 36 hours there was a trend toward a greater decrease in mean bilirubin for the fiberoptic group (-1.8 vs + 1.9 mg/dL; P = .08). There were no complications of therapy. The fiberoptic panel proved effective and safe; eliminated the need for eye patches; and permitted greater time for maternal-infant bonding.

Anemia, Hemolytic↗
PubMed1990

Improvement of neutrophil migration by systemic vitamin C in neonates.

The effect of oral vitamin C on chemotactic and random migration of neutrophils in 20 neonates (10 normal and 10 with suspected sepsis) was evaluated. Chemotaxis and random migration were studied between 24 and 48 hours of life, before and 24 hours after the administration of 400 mg (divided in four doses) of vitamin C. Chemotactic migration improved by 65% and random migration by 57% following vitamin C administration. The significant improvement in chemotaxis (P less than .01) and random migration may justify the inclusion of vitamin C as an adjunct to the therapy of neonatal sepsis.

Ascorbic Acid↗
PubMed1989

Ischemic injury to newborn rabbit ileum: protective role of human superoxide dismutase.

The effectiveness of human superoxide dismutase (hSOD) in the prevention of reperfusion injury was evaluated in a rabbit ileal loop model. Weanling white New Zealand rabbits, 6 weeks of age and weighing 500 to 1,000 g, were used. Intraluminal administration of SOD (5 mg/kg) was studied in 12 animals with each animal serving as its own control. In an additional 12 animals, parenteral SOD in a dose of 5 mg/kg in seven animals and 10 mg/kg in five animals was evaluated, while five additional control animals received parenteral saline. The effect of reperfusion injury was evaluated in each bowel loop by interruption of blood supply for five minutes, followed by reperfusion. Blood was drawn at 0, 16, 20, 24 hours in the parenteral group for measurement of hSOD levels by radioimmunoassay. The loops were studied pathologically for extent of mucosal damage. In the intraluminal group, nine of 12 loops without SOD v three of 12 loops with SOD showed necrosis when rendered ischemic (P = .0196). In the parenteral group 22 of 24 loops were normal when pretreated with SOD and subjected to ischemia v five of ten when no SOD was given (P = .0139). In the parenteral group, mean baseline level of hSOD was 0.42 +/- 0.26 micrograms/mL. Levels peaked at 16 hours (3.64 +/- 1.75 micrograms/mL) and progressively decreased at 20 hours (2.85 +/- 1.34 micrograms/mL) and 24 hours (1.82 +/- 1.15 micrograms/mL). This preliminary animal study suggests that hSOD may be an effective method for the prevention of postischemic bowel injury, adding to the literature on the protective effects of SOD in various models of intestinal ischemia.

Animals↗
PubMed1989

Phenytoin and phenobarbital concentrations in serum: a comparison of Ames Seralyzer with GLC, TDX, and EMIT.

A recently developed system for measuring antiepileptic drug concentrations was evaluated for phenytoin and phenobarbital. The apoenzyme reactive immunoassay system was compared with gas-liquid chromatography, EMIT, and TDX systems. Comparisons were performed with control specimens and with sera obtained from patients at three facilities. Precision for all methods was similar, with within-run and between-run coefficients of variation generally 5%. The accuracy of all methods was acceptable, but bias was present in some. However, measurements obtained by a nontechnical person (physician) in a clinical setting were sometimes inaccurate.

Chromatography, Gas↗