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PubMed2001

The effect of two different dosages of intravenous immunoglobulin on the incidence of recurrent infections in patients with primary hypogammaglobulinemia. A randomized, double-blind, multicenter crossover trial.

BACKGROUND: In patients with hypogammaglobulinemia, substitution with immunoglobulin is the treatment of choice to reduce both frequency and severity of bacterial infections. Even with treatment, however, infections still occur in these patients. OBJECTIVE: To determine whether doubling the standard dose of intravenous immunoglobulin would affect the incidence and duration of infections. DESIGN: Multicenter, double-blind, randomized, crossover study. SETTING: 15 outpatient clinics in the Netherlands. PATIENTS: 43 patients with primary hypogammaglobulinemia, 41 of whom completed the protocol. INTERVENTION: Patients received standard-dose immunoglobulin therapy for 9 months, followed by a 3-month washout period, and high-dose intravenous immunoglobulin therapy for 9 months, or vice versa. MEASUREMENTS: The primary outcome measures were total number and duration of infections. Other measures were periods of fever, hospital admissions, use of antibiotics, absence from school or work, and trough levels of serum immunoglobulin. Side effects from the study medication were also recorded. RESULTS: Compared with the standard dose of intravenous immunoglobulin (adults, 300 mg/kg of body weight every 4 weeks; children, 400 mg/kg every 4 weeks), high-dose therapy (adults, 600 mg/kg every 4 weeks; children, 800 mg/kg every 4 weeks) significantly reduced the number (3.5 vs. 2.5 per patient; P = 0.004) and duration (median, 33 days vs. 21 days; P = 0.015) of infections. Trough levels of IgG increased significantly during high-dose therapy. The incidence and type of side effects did not differ significantly for the two dosages. CONCLUSION: In patients with hypogammaglobulinemia, doubling the standard dose of intravenous immunoglobulin significantly reduced the number and duration of infections.

Adolescent↗
PubMed1991

Methotrexate in the treatment of steroid-dependent asthma.

A double-blind, placebo-controlled, crossover study was designed to compare steroid requirements between placebo and methotrexate (MTX) treatment in subjects with corticosteroid-requiring asthma. Subjects began with a steroid taper and then were randomized to a 3-month trial of drug or placebo therapy. Subjects received 15 mg of MTX a week or identical placebo. A 1-month washout period was completed before the crossover trial. Symptom scores, peak flow rates, spirometry, and beta-agonist frequency were closely monitored. Ten subjects completed the study. The average dose of prednisone during the placebo-treatment period was 11.97 mg/day compared to 8.37 mg/day while subjects were taking MTX. This was a 30% reduction in daily steroid requirement (p less than 0.01). Symptom scores and spirometry did not differ between the crossover trials, and overall clinical status was not altered. Complications from MTX were mild and included anorexia, alopecia, and stomatitis. All complications resolved with dose reduction or when MTX was stopped at the end of the study. No subjects withdrew from the study because of MTX complications. Low-dose MTX significantly reduced the steroid requirement in this group of subjects with steroid-dependent asthma. This reduction in steroid requirement was obtained without altering clinical status and without significant complication.

Adolescent↗
PubMedDate not supplied

The effects of a cholinesterase inhibitor are prominent in patients with fluctuating cognition: a part 3 study of the main mechanism of cholinesterase inhibitors in dementia.

Fluctuating cognition is evidenced in different forms of dementia and is accompanied by electroencephalographic (EEG) abnormalities. The authors hypothesize that cholinesterase inhibitors are effective mostly in patients with fluctuating cognition. Twenty-three patients affected by mild dementia with similar scores on Mini-Mental State Examination (MMSE), Alzheimer Disease Assessment Scale-cognitive subscale (ADAS-cog), and Unified Parkinson's Disease Rating Scale evaluation were classified in a group with fluctuating cognition (n = 11) and a group of nonfluctuators (n = 12). All patients were assigned randomly to the branches of a double-blind crossover study of donepezil (DPZ), a 5 to 10-mg dose, versus vitamin E, a 2000 IU dose, for 30 days. MMSE, ADAS-cog, University of California at Los Angeles Neuropsychiatric Inventory (NPI), quantitative EEG, P3 event-related potentials, choice reaction time variability (CRTV) were assessed at baseline and at the end of treatments. At the end of the crossover study all patients received DPZ for 6 months. The dominant EEG frequency variability, low EEG frequencies amplitude, the P3 latency and jitter, CRTV, and NPI was significantly different in the fluctuating cognition group than the nonfluctuating group at baseline (P < 0.001). Short-term DPZ administration induced a significant increase in MMSE scores, reduction of ADAS-cog and of NPI scores (P < 0.003-0.001), increase of EEG alpha activity and reductions of P3 latency and jitter, dominant frequency variability and CRTV (P < 0.009-0.001) in the fluctuating cognition group, and significant increases of MMSE scores (P = 0.03) and a decrease of P3 jitter and dominant frequency variability (P < 0.034-0.041) in the nonfluctuating group. Short-term DPZ effects differed significantly between fluctuating cognition and nonfluctuating patients (0.001). Significant effects of the 6-month observation were observed only in fluctuating cognition patients. Logistic analysis showed that P3 latency predicts the effect of DPZ (P = 0.04, P < 0.01) in the crossover study, and CRTV predicts the effect at the 6-month follow-up.

Aged↗
PubMed1985

Intermolecular recombination of the herpes simplex virus type 1 genome analysed using two strains differing in restriction enzyme cleavage sites.

Intermolecular recombination of herpes simplex virus type 1 (HSV-1) was studied by analysing the segregation of strain-specific restriction enzyme cleavage sites among progeny viruses produced after co-infection by two HSV-1 strains differing in eight restriction enzyme cleavage sites. Out of 93 progeny viruses examined, 51 clones were recombinant, and crossover sites of the recombinants were mapped on the HSV-1 genome. These sites were distributed evenly in the unique sequence of the L component (UL) and the recombination frequency in UL was estimated to be 1.12 per genome length, or 0.007 per kilobase pair. No evidence was obtained to support the existence of enhanced intermolecular recombination events in the regions containing inverted repeats and the L-S junction in comparison with the recombination frequency in UL. The finding of recombinants in an arrangement that minimized the number of crossover events suggested the participation of both of two arrangements of the L component of parental DNA (P or IS, and IL or ISL) in the generation of the recombinants. The possibility of a preference for P or IS over IL or ISL arrangements remains to be determined.

Chromosome Mapping↗
PubMedDate not supplied

Do different frequencies of self-monitoring of blood glucose influence control in type 1 diabetic patients?

The effect of altering the frequency of self-monitoring of blood glucose upon blood glucose control was assessed in 25 Type 1 diabetic patients. Patients entered a balanced, crossover study in which they were randomly allocated to three 12-week periods. During each period the frequency at which patients self-monitored their blood glucose was: (1) four-point profiles on 2 days per week; (2) four-point profiles on 1 day per week; (3) two-point profiles on every day of the week. There were no significant differences in mean blood glucose concentration, fructosamine or glycosylated haemoglobin concentrations during the three periods. There was no correlation between the frequency at which patients altered insulin doses and measures of metabolic control. Altering the frequency of blood glucose self-monitoring had a variable and uncertain influence upon the frequency at which patients altered insulin doses. Some patients felt unsafe monitoring blood glucose only four times per week. There was however no patient consensus on the best-liked regimen.

Adult↗
PubMed1980

Antiarrhythmic efficacy, pharmacokinetics and safety of N-acetylprocainamide in human subjects: comparison with procainamide.

The antiarrhythmic efficacy and pharmacokinetics of N-acetylprocainamide (NAPA), the major metabolite of procainamide, were investigated in 23 patients with chronic, high frequency ventricular ectopic depolarizations. An extensive trial design incorporated the approaches of (1) generation of dose-response relations, (2) randomized crossover, and (3) prolonged electrocardiographic monitoring. Seven patients with reproducible suppression of arrhythmias (70 percent or greater reduction in frequency) were thus identified. The mean plasma concentration of acecainide associated with efficacy was 14.3 micrograms/ml (range 9.4 to 19.5) and with side effects (primarily gastrointestinal) was 22.5 micrograms/ml (10.6 to 37.9). The antiarrhythmic response to procainamide did not predict response to acecainide; this finding implies that estimates of the antiarrhythmic contribution of acecainide concentrations achieved during long-term procainamide therapy are unlikely to be meaningful in a given person. The mean half-life of elimination after a single 500 mg dose of acecainide was 7.5 hours; this had prolonged significantly (p < 0.05) to 10.3 hours after higher dosages. No variable examined (including acetylator phenotype) was found to be a predictor of responsiveness to acecainide. Outpatient therapy (2 to 20 months) was not associated with the development of antinculear antibodies or the lupus syndrome; one patient's procainamide-induced arthritis resolved during therapy. Acecainide, unlike procainamide, is an agent whose pharmacokinetics allow long-term therapy on a practical schedule. It is effective in a subset of patients with ventricular arrhythmias yet appears much less likely to induce the lupus syndrome seen with the parent compound.

Acecainide↗
PubMed2003

Effects of contralateral sound stimulation on unit activity of ventral cochlear nucleus neurons.

The cochlear nucleus (CN) commissural connection represents the first opportunity for convergence of binaural information in the auditory brainstem. All major neuron types in the ventral CN (VCN) are innervated by a diverse population of cells in the contralateral VCN. This study examined the effect of contralateral sound stimulation on the spontaneous rates (SRs) of neurons in the VCN. Unit activity was recorded with silicon-substrate multichannel probes which allowed recordings from up to 16 sites simultaneously. On average, 30% of units showed short-latency (often only 2 ms greater than the latencies of ipsilateral sound-evoked responses) inhibition of SR by wideband contralateral noise bursts. Fewer units (4.5%) were excited by contralateral noise at sound levels low enough to exclude excitation by acoustic crossover. Both regular and irregular units in the anterior VCN (AVCN) and posterior VCN (PVCN) were inhibited by contralateral sound. Decrements in SR followed a monotonic function with increases in contralateral sound level, except where responses could be attributed to acoustic crossover. Restricting the contralateral noise bandwidth resulted in a frequency-specific inhibition, dominated by frequencies at and below the ipsilateral BF of the unit, consistent with anatomical findings of the tonotopic organization of the CN commissural pathway. The latencies of these effects are compatible with mono, di and tri-synaptic connections reflecting CN commissural pathway effects.

Acoustic Stimulation↗
PubMed1999

Gas production in human ingesting a soybean flour derived from beans naturally low in oligosaccharides.

BACKGROUND: Ingestion of soy products may cause excessive intestinal gas. This gas results from colonic bacterial fermentation of the indigestible oligosaccharides raffinose and stachyose, which are present in high concentrations in legumes. OBJECTIVE: The objective of the study was to compare gas production and gaseous symptoms in healthy volunteers after ingestion of 34 and 80 g soy flour made from either conventional soybeans or soybeans naturally low in indigestible oligosaccharides. DESIGN: In a double-blind, randomized, crossover protocol, breath hydrogen (an indicator of carbohydrate malabsorption), flatus frequency, and abdominal symptoms were assessed after subjects ingested the soy products and after 2 control meals (rice or lactose-hydrolyzed milk). RESULTS: The sum of breath-hydrogen concentrations for 8 h was significantly greater (P < 0.005) after 34 g conventional soy (60.4+/-9.4 ppm) than after low-oligosaccharide soy (34.3+/-8.1 ppm). Greater differences were observed with 80-g doses: 157.9+/-19.4 ppm after conventional soy and 50.8+/-6.8 ppm after low-oligosaccharide soy (P < 0.001). Flatus frequency (7.5+/-1.9 times/12 h) was significantly greater (P = 0.039) after ingestion of 80 g conventional soy than after the control, rice meal (3.2+/-0.8 times/12 h), whereas flatus frequency after the low-oligosaccharide soy meal (3.9+/-0.7 times/12 h) was comparable with that after the rice meal. There were no significant differences in the severity of other abdominal symptoms. CONCLUSION: Soy flour derived from low-oligosaccharide soybeans resulted in less gas production than that derived from conventional soybeans.

Adult↗
PubMed1995

Mutant rec-1 eliminates the meiotic pattern of crossing over in Caenorhabditis elegans.

Meiotic crossovers are not randomly distributed along the chromosome. In Caenorhabditis elegans the central portions of the autosomes have relatively few crossovers compared to the flanking regions. We have measured the frequency of crossing over for several intervals across chromosome I in strains mutant for rec-1. The chromosome is approximately 50 map units in both wild-type and rec-1 homozygotes, however, the distribution of exchanges is very different in rec-1. Map distances expand across the gene cluster and contract near the right end of the chromosome, resulting in a genetic map more consistent with the physical map. Mutations in two other genes, him-6 and him-14, also disrupted the distribution of exchanges. Unlike rec-1, individuals homozygous for him-6 and him-14 had an overall reduction in the amount of crossing over accompanied by a high frequency of nondisjunction and reduced egg hatching. In rec-1; him-6 and rec-1; him-14 homozygotes the frequency of crossing over was characteristic of the Him mutant phenotype, whereas the distribution of the reduced number of exchanges was characteristic of the Rec-1 pattern. It appears that these gene products play a role in establishing the meiotic pattern of exchange events.

Animals↗
PubMed1977

Multiple interactions of a DNA-binding protein in vivo. III. Phage T4 gene-32 mutations differentially affect insertion-type recombination and membrane properties.

We have investigated in in vivo roles of T4 gene-32 protein in recombination. We have studied the effects of gene-32 mutations under conditions that allow normal DNA replication and are permissive for progeny production. Under these conditions, certain gene-32 mutations specifically reduce insertion-type (short-interval) recombination but none affect crossover-type (long-interval) recombination (see Figure 5). Heterozygote frequencies in all gene-32 mutants are similar to or higher than in a gene-32+ background and are not correlated with recombination deficiencies. "Recombination-deficient" alleles are dominant or codominant over the "recombination-proficient" gene 32 mutation tsL171. This explains apparent discrepancies between a gene-32 map deduced from two-factor crosses and the map derived from three-factor crosses. We have also found that the "recombination proficient" mutation tsL171 and it homdoalleles suppress the characteristic plaque morphology of rII mutants. Under restrictive conditions, tsL171 is partially suppressed by rII mutations, which allow the use of host ligase in recombination. Our present and previous results are discussed in terms of current recombination models. We conclude that gene-32 protein functions in recombination by forming a complex with DNA, with recombination enzymes and with membrane components. Since gene-32 protein interacts with many components of this recombination complex, gene-32 mutations may differentially affect various recombination steps.

Alleles↗
PubMed1995

Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder.

OBJECTIVE: Because they found in an earlier study that inositol, an important intracellular second-messenger precursor, was effective against depression in open and double-blind trials, the authors studied its effectiveness against panic disorder. METHOD: Twenty-one patients with panic disorder with or without agoraphobia completed a double-blind, placebo-controlled, 4-week, random-assignment crossover treatment trial of 12 g/day of inositol. RESULTS: The frequency and severity of panic attacks and the severity of agoraphobia declined significantly more after inositol than after placebo administration. Side effects were minimal. CONCLUSIONS: The authors conclude that inositol's efficacy, the absence of significant side effects, and the fact that inositol is a natural component of the human diet make it a potentially attractive therapeutic for panic disorder.

Adult↗
PubMed2004

[The effects of rilmenidine on cardiac autonomic function in healthy volunteers].

INTRODUCTION AND OBJECTIVES: Rilmenidine is an antihypertensive drug whose antihypertensive effect occurs via a sympatholytic action on the central nervous system. However, the effects of rilmenidine on autonomic cardiovascular function are not clear. The aim of this study was to evaluate the acute effect of rilmenidine on autonomic cardiac function by measuring heart rate variability. SUBJECTS AND METHOD: A total of 20 healthy men (mean age, 263 years) were included in the study; 1 mg of rilmenidine or placebo was given to participants on different days in a double-blind crossover randomized study protocol. After drug administration, time domain and frequency domain parameters of heart rate variability were determined before and after 2 h with the patient in supine decubitus and during the handgrip exercise with 5-min electrocardiographic recordings. RESULTS: Rilmenidine caused an increase in mean RR values after administration when compared to pre-drug administration recordings with the patient in supine decubitus (929 ms vs 860 ms, P<.05), but this effect was not found in the placebo group. However, there were no differences in other time domain parameters or in any of the frequency domain parameters (normalized low frequency unit, normalized high frequency unit and low frequency/high frequency ratio) with the participant in supine position in either group. In addition, neither rilmenidine nor placebo modified heart rate variability parameters during the handgrip exercise. CONCLUSION: Administration of a single dose of rilmenidine increased vagal tone without affecting vagal modulation in the supine position. The absence of vagal tone increase during the handgrip exercise suggests that this effect of rilmenidine is minimal.

Adult↗
PubMed1995

[Variables related to the self-perceived health status: a population study].

OBJECTIVE: To study the self-perceived health status (PHS) of a community and its relationship to socio-economic variables of morbidity and frequency of attendance at the doctor's. DESIGN: A descriptive, crossover study. SETTING: A base Health District (HD). PATIENTS AND OTHER PARTICIPANTS: The general catchment area for the Occidente HD, Córdoba (N = 12,801 inhabitants) provided a random sample (for a p = 0.5, alpha error = 0.05 and with precision - 5%) of individuals over 15 (N = 384). MEASUREMENTS AND MAIN RESULTS: By means of a survey with a personal interview at home, socio-demographic data, PHS, chronic morbidity, consumption of pharmaceuticals and attendance at the doctor's were gathered. 32.9% (C.I. 95%: 27.4-37.1) stated a negative PHS. It was confirmed that older age (O.R. = 1.6; C.I. 1.04 - 1.08) and the existence of an acknowledged chronic pathology (O.R. = 6.84); C.I. 2.0 - 23.33) were the variables most strongly associated to a negative PHS. Chronic pathologies which were most intensely related to an unfavorable PHS were: Bronchitis (O.R. = 8.08; C.I. 3.02 - 21.5), Diabetes Mellitus (O.R. = 6.35; C.I., 1.03 - 38.9), Arthrosis (O.R. = 3.53; C.I. 2.03 - 6.13), Depression (O.R. = 3.53; C.I. 1.79 - 6.96), Arterial Hypertension (O.R. = 3.52; C.I. 1.63 - 7.63) and peptic ulcer (O.R. = 2.05; C.I. 1.02 - 4.11). CONCLUSIONS: The PHS could be useful as an overall indicator of the level of health of the population, as it is easy to obtain and has been shown to be linked to explanatory variables such as age and the presence of chronic disorders.

Adolescent↗
PubMed1994

Prospective, randomized comparison of high-frequency oscillatory ventilation and conventional mechanical ventilation in pediatric respiratory failure.

OBJECTIVE: To compare the effectiveness of high-frequency oscillatory ventilation with conventional mechanical ventilation in pediatric patients with respiratory failure. SETTING: Five tertiary care pediatric intensive care units. DESIGN: A prospective, randomized, clinical study with crossover. PATIENTS: Seventy patients with either diffuse alveolar disease and/or airleak syndrome were randomized to receive high-frequency oscillatory ventilation or conventional mechanical ventilation. INTERVENTIONS: Patients randomized to receive high-frequency oscillatory ventilation were managed, using a strategy that consisted of aggressive increases in mean airway pressure to attain the "ideal" lung volume and to achieve an arterial oxygen saturation of > or = 90%, with an FIO2 of < or = 0.6. Patients who were randomized to receive conventional mechanical ventilation were treated with a strategy that utilized increases in end-expiratory pressure and inspiratory time to increase mean airway pressure and to limit increases in peak inspiratory pressure. Target blood gas values were the same for both groups. Crossover to the alternate ventilator was required if the patient met defined criteria for treatment failure. MEASUREMENTS AND MAIN RESULTS: Physiologic data and ventilatory parameters were collected prospectively at predetermined intervals after randomization. Airleak Scores were derived daily, based on the chest radiograph and the patient's clinical condition. In the high-frequency oscillatory ventilation group, the PaO2/PAO2 ratio increased significantly and the oxygenation index (mean airway pressure x FIO2 x 100/PaO2) decreased significantly over time. There were no differences between the groups in duration of mechanical ventilation, frequency of airleak, Airleak Scores, or 30-day survival rates. Significantly fewer patients treated with high-frequency oscillatory ventilation required supplemental oxygenation at 30 days compared with patients managed with conventional ventilation. When ventilatory subgroups were compared, the patients managed with high-frequency oscillation only had significantly better ranked outcomes than patients managed with conventional ventilation only. CONCLUSIONS: Our results indicate that high-frequency oscillatory ventilation, utilizing an aggressive volume recruitment strategy, results in significant improvement in oxygenation compared with a conventional ventilatory strategy designed to limit increases in peak airway pressures. Furthermore, despite the use of higher mean airway pressures, the optimal lung volume strategy used in this study was associated with a lower frequency of barotrauma, as indicated by requirement for supplemental oxygen at 30 days, and improved outcome compared with conventional mechanical ventilation.

Child↗
PubMed2002

Additional lunchtime basal insulin during insulin lispro intensive therapy in a randomized, multicenter, crossover study in adults : a real-life design.

OBJECTIVE: This study was performed to evaluate whether an additional dose of NPH insulin at lunchtime might overcome the deleterious effects of waning basal insulinemia on pre-dinner and evening glucose values during insulin lispro intensive therapy with once daily basal insulin at night. RESEARCH DESIGN AND METHODS: The study was a 10-month multicenter, randomized, crossover trial. After a 2-month run-in period, subjects injected NPH insulin once (1 x NPH) or twice (2 x NPH) daily for 4 months in a randomized order. Adult patients were included if they had HbA(1c) levels <8.5%. Efficacy measures were HbA(1c) levels, 8-point glucose profiles, and the frequency of hypoglycemia. The statistical analysis included a within-patient comparison for crossover trials. RESULTS: In all, 104 patients completed the trial. The mean HbA(1c) level before randomization was 7.1 +/- 0.85%. The HbA(1c) levels did not change significantly within patients (t test, mean difference = 0.06%; 95% confidence interval [CI] -0.073 to 0.20). The pre-dinner blood glucose values were significantly lower during the 2 x NPH daily protocol, with a mean difference of 0.76 mmol/l (t test, P = 0.004; CI 0.25 to 1.3). In the evening, the frequency of hypoglycemia increased significantly during the 2 x NPH daily protocol with a median difference of 0.56 mild episodes/30 days (P = 0.001) and 6.9 severe episodes/patient year (P = 0.007), respectively. CONCLUSIONS: Equal HbA(1c) levels and increasing frequencies of hypoglycemia in the evening overshadow the slight improvement of the evening glucose profiles during a regimen with 2 x NPH daily insulin. Therefore, generalized use of a second injection of NPH insulin at lunchtime cannot be recommended to all adult patients with type 1 diabetes using intensive insulin lispro therapy.

Adult↗
PubMed2005

Discontinuities and unsynapsed regions in meiotic chromosomes have a cis effect on meiotic recombination patterns in normal human males.

During meiosis, homologous chromosome pairing is essential for subsequent meiotic recombination (crossover). Discontinuous chromosome regions (gaps) or unsynapsed chromosome regions (splits) in the synaptonemal complex (SC) indicate anomalies in chromosome synapsis. Recently developed immunofluorescence techniques (using antibodies against SC proteins and the crossover-associated MLH1 protein) were combined with fluorescence in situ hybridization (using centromere-specific DNA probes) to identify bivalents with gaps/splits and to examine the effect of gaps/splits on meiotic recombination patterns during the pachytene stage of meiotic prophase from three normal human males. Gaps were observed only in the heterochromatic regions of chromosomes 9 and 1, with 9q gaps accounting for 90% of these events. Most splits were also found in chromosomes 9 and 1, with 58% of splits occurring on 9q. Gaps and splits significantly altered the distribution of MLH1 foci on the SC. On gapped SC 9q, the frequency of MLH1 foci was decreased compared with controls, and single 9q crossovers tended toward a more distal distribution. Furthermore, the larger the gap the more distal the location of the MLH1 focus closest to the q arm's telomere. MLH1 foci on split SC 9 had distributions similar to those of gapped SC 9; however, splits did not change the frequencies of MLH1 foci on SC 9. This is the first demonstration that gaps and splits have an effect on meiotic recombination in humans.

Adaptor Proteins, Signal Transducing↗
PubMedDate not supplied

The efficacy of developmentally sensitive interventions and sucrose for relieving procedural pain in very low birth weight neonates.

BACKGROUND: Procedural pain management for very low birth weight (VLBW) neonates has been minimal or nonexistent in most neonatal intensive care units (NICUs). OBJECTIVES: To compare the efficacy of developmentally sensitive behavioral interventions (nonnutritive sucking via a pacifier, positioning) and sucrose for relieving procedural pain in VLBW infants and to determine the influence of contextual factors (gestational age, postnatal age, birth weight, severity of illness, frequency of painful procedures) on pain response. METHOD: In a prospective randomized crossover trial, pain was assessed in 122 VLBW neonates using the Premature Infant Pain Profile following four randomly ordered interventions during consecutive routine heel lance procedures. RESULTS: Significant differences in pain existed among treatment interventions (F = 16.20, p < .0001). The pacifier with sucrose (F = 24.09, p < .0001) and pacifier with sterile water (F = 9.00, p = .003) significantly reduced pain. Prone positioning did not decrease pain (F = 2.24, p = .137). Frequency of painful procedures approached significance in influencing pain response (F = 3.59, p = .01). CONCLUSIONS: The most efficacious interventions for reducing pain from single painful events were the pacifier with sucrose and the pacifier with sterile water. Research on the efficacy and safety of implementing these interventions, alone and in combination, for repeated painful procedures is needed. In addition, research is needed on the influence of implementing these interventions on pain response and clinical outcomes (e.g., health status and neurodevelopmental status) in VLBW neonates in the NICU.

Blood Specimen Collection↗
PubMed1989

EEG mean frequencies are sensitive indices of phenylalanine effects on normal brain.

We previously reported that changes in plasma phenylalanine (PHE) concentrations of 1000 microM or more adversely affected cognitive function and reduced mean frequency of the EEG power spectrum. In the present study, we characterized EEG effects of changes in plasma PHE from physiological to supraphysiological concentrations. Subjects were mentally normal children and adult volunteers with 3 different genotypes for phenylalanine hydroxylase (PHY): homozygous deficient, heterozygous, and homozygous normal. Double-blinded crossover studies were performed at equilibrium during PHE restriction and supplementation. The mean frequency of the power spectrum and the mean across a set of alpha-theta factors showed highly significant, reversible, generalized EEG slowing during PHE supplementation in subjects homozygous for PHY deficiency. Smaller but significant changes in EEG mean frequencies occurred in the heterozygous and normal subjects. Spectral profiles of EEG change were similar in both groups; the mean alpha-theta was more sensitive in the second group. Demonstration of EEG changes with PHE supplementation in normal individuals has important dietary implications.

Adult↗