Biomedical subjects

G J Badger

Publications and source records attributed to G J Badger.

At least 19 recordsLinked to original sources

PubMed2002

Comparison of the subjective, physiological, and psychomotor effects of atomoxetine and methylphenidate in light drug users.

This study compared the subjective, physiological, and psychomotor effects of atomoxetine and methylphenidate with placebo in healthy volunteers. Sixteen non-dependent light drug users participated in six experimental sessions, receiving placebo, atomoxetine (20, 45 and 90 mg) and methylphenidate (20 and 40 mg) using a double-blind, Latin square design. Subjective drug effects were assessed using Visual Analog Scales (VAS), the Addiction Research Center Inventory (ARCI) and Adjective Rating Scales (ARS). Psychomotor performance was evaluated using the Digit Symbol Substitution Test (DSST). Physiological measures were also collected throughout the sessions. Assessments were conducted before drug administration and 30, 60, 90, 120, 150, 180 and 240 min following dosing. Forty milligrams methylphenidate produced significant increases on the stimulant portions of the VAS and ARS and the benzedrine, amphetamine, morphine-benzedrine and lysergic acid diethylamine (LSD) subscales of the ARCI relative to placebo. Ninety mg atomoxetine was reported to be unpleasurable relative to placebo as indicated by significant increases on the 'bad' and 'sick' portions of the VAS, and on the LSD subscale of the ARCI. Compared with placebo, both methylphenidate doses significantly increased systolic blood pressure (BP) and heart rate (HR). For atomoxetine, 90 mg increased diastolic BP, 45 and 90 mg increased systolic BP, and all three doses increased HR relative to placebo. Neither compound produced significant differences from placebo on DSST performance. These results suggest that atomoxetine does not induce subjective effects similar to methylphenidate and suggest that it is unlikely that atomoxetine will have abuse liability.

Adolescent↗

PubMed2002

Comparison of fetal growth estimates based on birth weight and ultrasound references.

OBJECTIVE: To compare three different methods for modeling fetal weight gain during the third trimester of pregnancy. METHODS: Ultrasound and live birth weight data were used to construct three models for defining fetal growth during the third trimester: longitudinal ultrasound estimates of fetal weight obtained serially at 3-4 week intervals in 50 uncomplicated, well-dated pregnancies between 19 and 40 weeks' gestation; cross-sectional ultrasound estimates of fetal weight obtained from 2018 ultrasound examinations of singleton, non-anomalous fetuses between 24 and 39 weeks' gestation; and cross-sectional birth weight data obtained from 9553 live singleton, non-anomalous neonates between 24 and 43 completed weeks. Analysis was performed by pairwise partial f test to compare regression curves and zeta test for comparison of mean weekly weight gain. A value of p < 0.05 was accepted for significance. RESULTS: Derived regression lines depicting fetal size across gestation were significantly different from each other (f tests, p < 0.05). Estimates of mean fetal weight were significantly different between the three different models at specific gestational ages. Significant weekly variations in fetal weight gain were observed within the raw cross-sectional data sets, both for ultrasound-estimated fetal weight (range 91-278 g/week) and birth weight (65-309 g/week). CONCLUSIONS: Each of the methods used to model normal fetal weight gain in the third trimester defined a distinct pattern of fetal growth. Normal fetal growth, defined longitudinally, was most closely matched by a combination of cross-sectional ultrasound-derived estimated fetal weight in preterm gestation below 34 weeks' gestation and live birth weight at or beyond 34 weeks.

Birth Weight↗

PubMed2001

Limits to buprenorphine dosing: a comparison between quintuple and sextuple the maintenance dose every 5 days.

The relative efficacy of quintuple and sextuple buprenorphine dosing in abating withdrawal symptoms for 120 h was compared in opioid-dependent outpatients. Fourteen subjects received buprenorphine in a double-blind, placebo-controlled, cross-over design. Daily sublingual maintenance doses were 4 mg/70 kg (n=4) and 8 mg/70 kg (n=10). After a stabilization period of daily maintenance administration, subjects received quintuple (5x daily maintenance dose) and sextuple (6x daily maintenance dose) doses every 120 h. Measures of opioid agonist and withdrawal effects were assessed daily. Subjective ratings of withdrawal were significantly greater than baseline ratings beyond 96-h post dosing under both regimens. There was no evidence, however, that those subjective ratings of withdrawal differed between the two regimens. Thus, these data suggest that sextuple buprenorphine dosing, administered every 5 days, does not abate opioid-withdrawal beyond 96 hours.

Adult↗

PubMed2001

The effect of weightbearing and external loading on anterior cruciate ligament strain.

A force balance between the ligaments, articular contact, muscles and body weight maintains knee joint stability. Thus, it is important to study anterior cruciate ligament (ACL) biomechanics, in vivo, under weightbearing conditions. Our objective was to compare the ACL strain response under weightbearing and non-weightbearing conditions and in combination with three externally applied loadings: (1) anterior-posterior shear forces, (2) internal-external torques, and (3) varus-valgus moments. A strain transducer was implanted on the ACL of 11 subjects. All joint loadings were performed with the knee at 20 degrees of flexion. A significant increase in ACL strain was observed as the knee made the transition from non-weightbearing to weightbearing. During anterior shear loading, the strain values produced during weightbearing were greater than those of the non-weightbearing knee (shear loads <40N). At higher shear loads, the strain values became equal. During axial torsion, an internal torque of 10Nm strained the ACL when the knee was non-weightbearing while an equivalent external torque did not. Weightbearing significantly increased ACL strain values in comparison to non-weightbearing with the application of external torques and low internal torques (<3Nm). The strains became equal for higher internal torques. For V-V loading, the ACL was not strained in the non-weightbearing knee. However, weightbearing increased the ACL strain values over the range of moments tested. These data have important clinical ramifications in the development of rehabilitation protocols following ACL reconstruction since weightbearing has been previously thought to provide a protective mechanism to the healing graft.

Adult↗

PubMed2001

Plasma volume expansion in early pregnancy.

OBJECTIVE: To determine the time course of plasma volume expansion in early pregnancy. METHODS: We prospectively measured plasma volume by Evans blue dye dilution during the menstrual (cycle day 2--3), follicular (cycle day 9--10), and luteal phases (cycle day urinary leutinizing hormone [LH] surge plus 9--10) of the menstrual cycle and at three additional time points (LH surge + 16 days, LH surge + 28 days, and LH surge + 70 days) in women achieving pregnancy. Twenty-one subjects were examined during 38 menstrual cycles to establish baseline menstrual cycle data. Ten subjects conceived within 1 year of menstrual cycle studies. All ten pregnancies were viable and reached the third trimester. Analyses used repeated-measures analysis of variance with P <.05 accepted for significance. RESULTS: Mean plasma volume was found to change significantly across the period of observation (P <.008) in those who conceived. Plasma volume at LH surge + 70 days (12 menstrual weeks, 2320 +/- 280 mL) was greater than either menstrual cycle estimates or early pregnancy estimates of plasma volume. There was no difference in plasma volume at LH surge + 16 days (2077 +/- 288 mL) or LH surge + 28 days (2010 +/- 271 mL) compared with menstrual cycle measurements during the menstrual phase (2156 +/- 292 mL), follicular phase (2036 +/- 280 mL), and luteal phase (2120 +/- 425 mL). There was no significant difference between those who conceived and those who did not in their mean menstrual cycle plasma volume. CONCLUSION: Plasma volume expansion in early human pregnancy cannot be identified until after the sixth menstrual week. By 12 menstrual weeks, plasma volume has expanded by approximately 14% +/- 12% (mean +/- SD) over follicular phase measurements.

Adult↗

PubMed2001

The gastrocnemius muscle is an antagonist of the anterior cruciate ligament.

Since the proximal tendon of the gastrocnemius muscle wraps around the posterior aspect of the tibia, its contraction could potentially strain the anterior cruciate ligament (ACL) by pushing the tibia anteriorly. However, the relationship between contraction of the gastrocnemius muscle and ACL strain has not been studied in vivo. The objectives of this study were to evaluate the ACL strain response due to isolated contractions of the gastrocnemius muscle and to determine how these strains are affected by cocontraction with the hamstrings and quadriceps muscles. Six subjects with normal ACLs participated in the study; they underwent spinal anesthesia to ensure that their leg musculature was relaxed. Transcutaneous electrical muscle stimulation (TEMS) was used to induce contractions of the gastrocnemius, quadriceps and hamstrings muscles while the strains in the anteromedial bundle of the ACL were measured using a differential variable reluctance transducer. The ACL strain values produced by contraction of the gastrocnemius muscle were dependent on the magnitude of the ankle torque and knee flexion angle. Strains of 2.8% and 3.5% were produced at 5 degrees and 15 degrees of knee flexion, respectively. The ACL was not strained at 30 degrees and 45 degrees. Changes in ankle angle did not significantly affect these strain values. Co-contraction of the gastrocnemius and quadriceps muscles produced ACL strain values that were greater than those produced by isolated activation of either muscle group when the knee was at 15 degrees and 30 degrees. Co-contraction of the gastrocnemius and hamstrings muscles produced strains that were higher than those produced by the isolated contraction of the hamstrings muscles. At 15 degrees and 30 degrees of knee flexion. the co-contraction strain values were less than those produced by stimulation of the gastrocnemius muscle alone. This study verified that the gastrocnemius muscle is an antagonist of the ACL. Since the gastrocnemius is a flexor of the knee, this finding may have important clinical ramifications in ACL rehabilitation since flexor torques are generally thought to be protective of a healing ACL graft.

Adult↗

PubMed2001

Examining the limits of the buprenorphine interdosing interval: daily, every-third-day and every-fifth-day dosing regimens.

AIMS: Opioid-dependent outpatients may be more likely to present for pharmacological treatment if less than daily dosing can be arranged. These studies compared opioid withdrawal symptoms during 24-, 72-, and 120-hour buprenorphine dosing regimens and evaluated participants' preferences for these different dosing regimens. PARTICIPANTS: Thirty-three opioid-dependent participants received daily sublingual maintenance doses of 4 mg/70 kg (n = 14) or 8 mg/70 kg (n = 19) of liquid buprenorphine. METHODS: In Study I participants received, in a random order, three dosing regimens for five repetitions of each: daily maintenance doses every 24 hours (4 or 8 mg/70 kg), triple the daily maintenance dose every 72 hours (12 or 24 mg/70 kg) and quintuple the daily maintenance dose every 120 hours (20 or 40 mg/70 kg). Doses were administered under double-blind procedures, and placebos were administered on the interposed days during the latter two regimens. Subjective and observer ratings of opioid withdrawal symptoms were assessed daily prior to receipt of each dose. In Study II, a new group of participants received each of the three dosing regimens under open-dosing procedures and then chose between the different dosing regimens. FINDINGS: Opioid withdrawal symptoms increased significantly during the every-fifth-day dosing regimen in both the blind- and open-dosing studies. In the choice phase of Study II, only one participant (7%) chose quintuple-every-fifth-day dosing over all other dosing options. CONCLUSIONS: These results suggest that the maximum duration of action of buprenorphine is less than 5 days when five times the daily maintenance dose is provided.

Adult↗

PubMed2001

Do pediatric trauma centers have better survival rates than adult trauma centers? An examination of the National Pediatric Trauma Registry.

BACKGROUND: Pediatric trauma centers (PTCs) were developed to improve the survival of injured children, but it is currently unknown if children admitted to PTCs are more likely to survive than those admitted to adult trauma centers (ATCs). METHODS: Fifty-three thousand one hundred thirteen pediatric trauma cases from 22 PTCs and 31 ATCs included in the National Pediatric Trauma Registry were reviewed to evaluate survival rates at PTCs and ATCs. RESULTS: Overall, 1,259 children died. The raw mortality rate was lower at PTCs (1.81% of 32,554 children) than at ATCs (3.88% of 18,368 children). However, patients admitted to ATCs were more severely injured. When Injury Severity Score, Pediatric Trauma Score, mechanism (blunt or penetrating), gender, age, clustering, and American College of Surgeons (ACS) verification status were controlled for using a single logistic regression model, there was no statistically significant difference in survival between PTCs and ATCs (odds ratio, 1.02; 95% confidence interval, 0.83-1.26; p = 0.587). A similar comparison of the 12 ACS-verified trauma centers with the 41 nonverified centers showed verification to be associated with improved survival (odds ratio, 0.75; 95% confidence interval, 0.58-0.97; p = 0.013). CONCLUSION: Although PTCs have higher overall survival rates than ATCs, this difference disappears when the analysis controls for Injury Severity Score, Pediatric Trauma Score, age, mechanism, and ACS verification status. ACS-verified centers have significantly higher survival rates than do unverified centers.

Adult↗

PubMed2001

Sensitivity of nicotine-containing and de-nicotinized cigarette consumption to alternative non-drug reinforcement: a behavioral economic analysis.

A previous report from our laboratory showed similar measures of reinforcing efficacy for nicotine-containing and de-nicotinized cigarettes when each cigarette type was presented alone. The present experiment further compared the reinforcing efficacy of nicotine-containing and de-nicotinized cigarettes by assessing the effects of alternative non-drug reinforcement on self-administration of both cigarette types. Eight human subjects responded on a progressive-ratio schedule in which the number of plunger pulls required for standardized cigarette puffs increased across sessions. Responding for the two types of cigarette was examined when each was available alone and when the concurrent opportunity to earn money was available. Consumption of nicotine-containing and de-nicotinized cigarettes was decreased by both increases in price and by the concurrent availability of money. The two cigarettes types did not differ in their sensitivity to price or alternative non-drug reinforcement. These results replicate our previous report of similar measures of reinforcing efficacy for the two cigarette types when each was presented alone, and extend our previous findings to a choice situation involving an alternative non-drug reinforcer. These data suggest the importance of further examination of non-pharmacological variables in the maintenance of drug taking and the sensitivity of drug taking to alternative non-drug sources of reinforcement. Factors potentially contributing to the maintenance of smoking the de-nicotinized cigarettes (i.e. conditioned reinforcement, primary reinforcement by respiratory stimulation, instructional control, demand characteristics) are also discussed.

Adult↗

PubMed2001

Behavioral economics of human drug self-administration: progressive ratio versus random sequences of response requirements.

Progressive-ratio (PR) schedules have been used widely to examine the relationship between drug consumption and drug price (i.e. demand curves) in the study of the behavioral economics of drug abuse. Sequential effects produced by the increasing response requirements of progressive-ratio schedules might influence the shape of demand curves for drug reinforcers. This study compared progressive ratio schedule and random sequences of ratio requirements, each incremented across sessions in a within-subject design, to determine if they produced similar behavioral economic and traditional measures of reinforcer efficacy. Self-administration of standardized cigarette puffs (70 cc each) was studied with eight smokers. Puffs were available at nine ratio requirements (e.g. 3, 100, 300, 600, 1500, 3000, 6000, 12000, 24000 responses/three puffs), presented in ascending (progressive-ratio schedule) or random sequence across daily sessions. The parameter estimates obtained on measures of reinforcing efficacy (e.g. breakpoint, peak response rates, elasticity of demand) were similar for both methods of incrementing prices. We found no evidence that PR and random sequences of fixed-ratio (FR) schedules, incremented across daily sessions, resulted in different demand curves.

Adult↗

PubMed2001

Biomechanical response to acupuncture needling in humans.

During acupuncture treatments, acupuncture needles are manipulated to elicit the characteristic "de qi" reaction widely viewed as essential to acupuncture's therapeutic effect. De qi has a biomechanical component, "needle grasp," which we have quantified by measuring the force necessary to pull an acupuncture needle out of the skin (pullout force) in 60 human subjects. We hypothesized that pullout force is greater with both bidirectional needle rotation (BI) and unidirectional rotation (UNI) than no rotation (NO). Acupuncture needles were inserted, manipulated, and pulled out by using a computer-controlled acupuncture needling instrument at eight acupuncture points and eight control points. We found 167 and 52% increases in mean pullout force with UNI and BI, respectively, compared with NO (repeated-measures ANOVA, P < 0.001). Pullout force was on average 18% greater at acupuncture points than at control points (P < 0.001). Needle grasp is therefore a measurable biomechanical phenomenon associated with acupuncture needle manipulation.

Acupuncture↗

PubMed2001

Alcohol dependence among cocaine-dependent outpatients: demographics, drug use, treatment outcome and other characteristics.

OBJECTIVE: Concurrent dependence on alcohol is common among those seeking treatment for cocaine dependence. More information is needed about differences between those with and without concurrent alcohol dependence, including possible special treatment needs or outcome differences. METHOD: Data were obtained from 302 adults (70% men) enrolled in outpatient treatment for cocaine dependence. Individuals who did and those who did not meet criteria for alcohol dependence were compared on demographics, drug use, treatment outcome and other variables. RESULTS: With regard to cocaine use, alcoholics were more likely than nonalcoholics to report an intranasal route of administration, use of cocaine in social settings, more simultaneous use of cocaine and alcohol, and more adverse consequences of their cocaine use. With regard to alcohol use, alcoholics reported consuming alcohol more frequently and in larger amounts, had longer drinking histories and were more likely than nonalcoholics to report increases in alcohol consumption when using cocaine. Alcoholics were heavier cigarette smokers than nonalcoholics and reported more severe employment, legal, family and psychiatric problems. There were overall improvements in both groups from intake through 12 months after treatment. With regard to treatment retention and cocaine abstinence, alcoholics had better outcomes than nonalcoholics when treated with intensive behavioral counseling plus incentives, but the reverse was true when treated with control treatments. CONCLUSIONS: Compared with nonalcoholic cocaine-dependent subjects, codependent patients exhibit a wider array of problems, many of which merit professional attention. Both alcoholics and nonalcoholics exhibit substantial improvements during treatment, with alcoholics perhaps requiring extra treatment efforts for successful outcomes.

Adult↗

PubMed2001

Effects of infusion rate of intravenously administered morphine on physiological, psychomotor, and self-reported measures in humans.

Although the rate of onset of a drug effect is commonly believed to contribute to a drug's abuse liability, only a few systematic experimental studies have been conducted examining this notion. The present study determined the profile of physiological, psychomotor, and self-reported effects of infusion rate (a key means of manipulating onset of drug action) of intravenously administered morphine, the prototypical analgesic with a known abuse liability in human participants. Two doses of morphine sulfate (5 and 10 mg/70 kg, i.v.) and a placebo dose (0 mg/70 kg, i.v.) were administered to healthy volunteers under three infusion rates (2 min bolus, 15 min, and 60 min). Faster infusions of morphine produced greater positive subjective effects than slower infusions on visual analog scale measures of good drug effect, drug liking, and high. Faster infusions also resulted in greater self-reported drug effects and opioid agonist effects, without producing significant physiological or psychomotor impairment. Importantly, faster rates of drug infusion produced significantly higher morphine plasma levels than slower rates, and morphine plasma levels followed a similar pattern and timing of peak effect as the self-reported effects of the drug. Moreover, morphine produced dose-dependent increases in self-reported drug effects, opioid agonist effects, and morphine plasma levels in the study. Results suggest that the pharmacokinetic properties of a drug, including the dosage administered and the rate of at which it is administered may function to jointly affect the abuse liability of the drug.

Adolescent↗

PubMed2000

Needle sharing in opioid-dependent outpatients: psychological processes underlying risk.

Needle sharing contributes to the spread of the human immunodeficiency virus and other health concerns and remains a persistent problem among injection drug users. We determined whether needle sharing may be related to the discounting of the value of delayed outcomes. Outpatients in treatment for heroin dependence indicated preference for immediate versus delayed hypothetical monetary and heroin outcomes in a titration procedure that determined indifference points at various delays. The degree to which the delayed outcomes lost value was estimated with a nonlinear decay model. Participants who agreed to share a needle in a scenario (N=15) discounted delayed money more steeply than did the nonsharing group (N=17). Both groups discounted delayed heroin more steeply than delayed money. Persistent needle sharing may be related to the relative inability of delayed outcomes to impact current behavior. Training to mitigate the effect of delay on outcome value may offer reductions in needle sharing and drug abuse.

Adult↗

PubMed2000

Decrease in trunk muscular response to perturbation with preactivation of lumbar spinal musculature.

STUDY DESIGN: An experimental study of healthy subjects' trunk muscle responses to force perturbations at differing angles and steady state efforts. OBJECTIVES: To determine whether increased preactivation of muscles was associated with decreased likelihood of muscular activation in response to a transient force perturbation. SUMMARY OF BACKGROUND DATA: Trunk stability (ability to return to equilibrium position after a perturbation) requires the stiffness of appropriately activated muscles to prevent buckling and consequent "self-injury." Therefore, greater trunk muscle preactivation might decrease the likelihood of reflex muscle responses to small perturbations. METHODS: Each of 13 subjects stood in an apparatus with the pelvis immobilized. A harness around the thorax provided a preload and a force perturbation by a horizontal cable and a movable pulley attached to one of five anchorage points on a wall track surrounding the subject at angles of 0 degrees, 45 degrees, 90 degrees, 135 degrees, and 180 degrees to the forward direction. Subjects first equilibrated with a preload effort of nominally 20% or 40% of their maximum extension effort. Then a single full sine-wave force perturbation pulse of nominal amplitude, 7.5% or 15% of maximum effort, duration 80 milliseconds or 300 milliseconds, was applied at a random time, with three repeated trials of each test condition. The applied force (via a load cell) and the electromyographic activity of six right and left pairs of trunk muscles were recorded. Muscle responses were detected by two methods. 1) Shewhart method: electromyographic signal greater than "baseline" values by more than three standard deviations, and 2) Mean Electromyographic Difference method: mean electromyographic signal in a time window 25 to 150 milliseconds after the force perturbation greater than that in a 25- to 150-millisecond window before the perturbation. RESULTS: Lower preload efforts were associated with more muscle responses (overall mean response detection rate = 33% at low preload and 25% at high preload). Using the Shewhart method, there were significant differences by effort (P<0.05) for all abdominal muscles and for all left dorsal muscles except multifidus. Using the Mean Electromyographic Difference method, there were significant differences by effort (P<0.05) for the same dorsal muscles, but only for one of the abdominal muscles. CONCLUSIONS: Findings are consistent with the hypothesis that the spine can be stabilized by the stiffness of activated muscles, obviating the need for active muscle responses to perturbations.

Adult↗

PubMed2000

Chronic inflammatory demyelinating polyradiculoneuropathy: a study of proposed electrodiagnostic and histologic criteria.

OBJECTIVE: To examine the sensitivity of the 3 proposed electrodiagnostic (EDX) criteria for demyelination, the sensitivity and specificity of the proposed Ad Hoc Subcommittee of the American Academy of Neurology AIDS [Acquired Immunodeficiency Syndrome] Task Force histologic criteria (AAN criteria), the degree of agreement among these criteria, and the diagnostic value of sural nerve histologic criteria in patients with idiopathic chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). DESIGN AND METHODS: A retrospective analysis of 24 patients with idiopathic CIDP and 12 patients with diabetic polyneuropathy (DP) who underwent comparable testing of clinical, histologic, and EDX features. RESULTS: We found 42%, 50%, and 79% sensitivity of the proposed EDX, AAN teased fiber, and AAN electron microscopic (EM) criteria, respectively, for demyelination in CIDP. The specificity of the proposed AAN teased fiber and EM criteria for demyelination was greater than 80% when tested against patients with DP. There was lack of agreement between the EDX and histologic criteria. Almost two thirds of patients with CIDP who met the EM criteria but none of the EDX criteria for demyelination showed a favorable response to immunomodulatory therapy. CONCLUSIONS: Sural nerve histologic criteria offer unique sensitivity and acceptable specificity toward the diagnosis of CIDP. Sural nerve biopsy should be considered when a clinical suspicion of CIDP remains in patients who do not meet the proposed EDX criteria for demyelination.

Adult↗

PubMed2000

Morbidity and mortality among very-low-birth-weight neonates with intrauterine growth restriction. The Vermont Oxford Network.

OBJECTIVE: We sought to determine the associations between intrauterine growth restriction and neonatal morbidity and mortality, as well as the impact of prenatal glucocorticoid administration on the frequency of specific complications of prematurity among neonates with intrauterine growth restriction. STUDY DESIGN: We examined the association between intrauterine growth restriction and adverse neonatal outcomes in a population of 19,759 singleton very-low-birth-weight neonates without major birth defects. We included neonates from 25 to 30 weeks' gestation entered in the Vermont Oxford Network database between 1991 and 1996 by 196 institutions. Intrauterine growth restriction was defined as the 10th percentile for birth weight according to the 1993 US national statistics. Odds ratios were estimated according to stepwise logistic regression for each neonatal outcome. Potential explanatory variables included gestational age, intrauterine growth restriction, race, prenatal care, prenatal glucocorticoid administration, route of delivery, fetal sex, and birth within versus postnatal transfer to a network institution. RESULTS: There was a statistically significant association of intrauterine growth restriction with neonatal death (odds ratio, 2.77; 95% confidence interval, 2.31-3. 33), necrotizing enterocolitis (odds ratio, 1.27; 95% confidence interval, 1.05-1.53), and respiratory distress syndrome (odds ratio, 1.19; 95% confidence interval, 1.03-1.36). There was a trend (P <. 10) toward association of intrauterine growth restriction with increased risks of intraventricular hemorrhage (odds ratio, 1.13; 95% confidence interval, 0.99-1.29) and severe intraventricular hemorrhage (grades III and IV; odds ratio, 1.25; 95% confidence interval, 0.98-1.59). Maternal prenatal glucocorticoid administration was associated with significantly lower risks of respiratory distress syndrome (odds ratio, 0.51; 95% confidence interval, 0.44-0.58), intraventricular hemorrhage (odds ratio, 0.67; 95% confidence interval, 0.61-0.73), severe intraventricular hemorrhage (odds ratio, 0.50; 95% confidence interval, 0.43-0.57), and death (odds ratio, 0.54; 95% confidence interval, 0.48-0.62). The benefits of prenatal glucocorticoid therapy for growth-restricted newborns were similar to those among normally grown infants. CONCLUSIONS: Intrauterine growth restriction within the range of 501 to 1500 g birth weight is associated with increased risks of neonatal death, necrotizing enterocolitis, and respiratory distress syndrome. Prenatal corticosteroid use was associated with decreased risks of all outcomes studied except necrotizing enterocolitis. We found no evidence that this benefit was dependent on fetal size.

Cerebral Hemorrhage↗

PubMed2000

Contingent reinforcement increases cocaine abstinence during outpatient treatment and 1 year of follow-up.

This study assessed whether contingent incentives can be used to reinforce cocaine abstinence in dependent outpatients. Seventy cocaine-dependent outpatients were randomized into 2 conditions. All participants received 24 weeks of treatment and 1 year of follow-up. The treatment provided to all participants combined counseling based on the community reinforcement approach with incentives in the form of vouchers exchangeable for retail items. In 1 condition, incentives were delivered contingent on cocaine-free urinalysis results, whereas in the other condition incentives were delivered independent of urinalysis results. Abstinence-contingent incentives significantly increased cocaine abstinence during treatment and 1 year of follow-up compared with noncontingent incentives.

Adult↗