Assessment of morbidity following insertion of fixed preoperative orthopedic appliance in infants with complete cleft lip and palate

OBJECTIVE

To examine physiologic and behavioral indicators of pain within the first 24 hours following insertion of the fixed presurgical orthopedic appliance (FPOA) under general anesthesia in infants with unilateral and bilateral complete cleft lip and palate.

METHODS

The study sample included 109 infants who had either a dentomaxillary appliance (DMA) or an elastomeric chain premaxillary retraction (ECPR) appliance. Vital signs and FLACC (Face, Legs, Activity, Cry, Consolability) scores were used to measure the outcomes.

RESULTS

There was an initial postoperative increase in the median heart rate. Heart rate returned to the median baseline level by 8 hours. The median systolic blood pressure increased postoperatively and remained elevated throughout the time of evaluation. The median respiratory rate remained below that at baseline throughout the study period. The highest mean change in FLACC measurements was observed approximately 2 hours postoperatively. By 3 hours postoperatively, the scores decreased.

CONCLUSIONS

Although there was a large individual variability, the FLACC scores became reduced after 3 hours following surgical insertion of the DMA and the ECPR appliance.

Transthoracic esophagectomy with radical mediastinal and abdominal lymph node dissection and cervical esophagogastrostomy for esophageal carcinoma

BACKGROUND

Several techniques for esophageal resection have been reported. This study examines the morbidity, mortality, and early survival of patients after transthoracic esophagectomy for esophageal carcinoma using current staging techniques and neoadjuvant therapy. The technique includes right thoracotomy, laparotomy, and cervical esophagogastrostomy (total thoracic esophagectomy) with radical mediastinal and abdominal lymph node dissection.

METHODS

Three hundred forty-two patients had surgery for esophageal carcinoma between 1989 and 2000 at our institution. Two hundred fifty consecutive patients had esophagectomy using this technique. Kaplan-Meier curves and univariate and multivariate analyses were performed by postsurgical pathologic stage.

RESULTS

Median age was 62.7 years (31 to 86 years). Fifty-nine were female. Eighty-one percent (202) had induction chemotherapy (all patients with clinical T3/4 or N1). Early postoperative complications included recurrent laryngeal nerve injury (14% [35]), chylothorax (9%, [22]), and leak (8%, [19]). Median length of stay was 13 days (5 to 330 days). In-hospital or 30-day mortality was 3.6% (9). Overall survival at 3 years was 44%; median survival was 25 months, and 3-year survival by posttreatment pathologic stage was: stage 0 (complete response) (n = 60), 56%; stage I (n = 32), 65%; stage IIA (n = 67), 41%; stage IIB (n = 30), 46%; and stage III (n = 49), 17%. Mean follow-up was 24 months (SEM 1.6, 0 to 138 months). Five patients with tumor in situ, 6 patients with stage IV disease, and 1 patient who could not be staged (12 pts) were excluded from survival and multivariate calculations. In univariate and different models of multivariate analysis, age more than 65 years, posttreatment T3, and nodal involvement were predictive of poor survival. For univariate analysis, p = 0.002, p = 0.004, p = 0.02, respectively; for multivariate analysis, p = 0.001, p = 0.003, p = 0.02, respectively.

CONCLUSIONS

Total thoracic esophagectomy with node dissection for esophageal cancer appears to have acceptable morbidity and mortality with encouraging survival results in the setting of neoadjuvant therapy. Patients who show complete response after induction chemoradiotherapy appear to have improved long-term survival.

Brain ATP metabolism in hypoxia resistant mice fed guanidinopropionic acid

Feeding beta-guanidinopropionic acid (GPA), a competitive inhibitor of creatine transport, decreases mortality and increases brain ATP stability in hypoxic mice. To study brain ATP metabolism in GPA-fed animals, respiratory rates were measured in grey matter and white matter slices as well as cerebral hemisphere mitochondria from GPA-fed mice and rats. Creatine kinase and adenylate kinase activities were measured in rat cerebral grey matter and white matter. Respiratory rates and oxidative phosphorylation were the same in GPA-fed mice and control mice. The adenylate kinase activity increased 50% and creatine kinase showed a small decrease in grey matter. In white matter, creatine kinase increased 50% while adenylate kinase decreased. Thus, GPA produces opposite adaptive changes in adenylate kinase and creatine kinase in grey matter and in white matter. These results suggest that the creatine kinase reaction in grey matter acts to regulate cellular ADP and ATP concentrations.

Reports of pain by children undergoing rapid palatal expansion

PURPOSE

This study described and quantified the prevalence, timing, and intensity of pain during the expansion phase of rapid palatal expansion (RPE) in children and investigated whether pain was related to age, sex, or rate of expansion.

METHODS

Ninety-seven children, 38 males and 59 females, between the ages of 5 to 13 years (median 7.7 years) undergoing RPE procedures with the Hyrax, Dentaurum, Newtown, PA, appliance were surveyed. The appliance was expanded with either one or two turns (1/4 mm/turn) per day based on the provider's preference. The child's pain response was measured no more than 5 minutes after each turn for the entire period of expansion using both the Facial Pain Scale and the Color Analog Scale.

RESULTS

Ninety-eight percent of the children reported at least some pain during RPE. The highest levels of pain were reported during the first 10 turns with the greatest intensity during the first 6 turns and a steadily decreasing amount of pain thereafter. Pain medication was taken after 7% of the expansion turns in the study with the majority of children taking the medication during the first 6 turns. Forty-eight percent of the children took pain medication at least once during the expansion phase of RPE. There was no difference in either reported pain or use of pain medication based on age, sex, or stage of dentition. During the first 10 turns, children whose rate of expansion was two turns/day were more likely to report pain and take pain medication than children whose rate of expansion was one turn/day, thereafter there were no differences.

CONCLUSIONS

The vast majority of children undergoing the active phase of rapid palatal expansion with a Hyrax appliance report pain. The pain generally occurs during the initial phase of expansion and diminishes thereafter, with two turns/day resulting in reports of pain greater than those expanding only once/day.

Outcome at age 4 years in offspring of women with maternal phenylketonuria: the Maternal PKU Collaborative Study

CONTEXT

Untreated maternal phenylketonuria (PKU) increases risk for developmental problems in offspring. The extent to which this risk is reduced by maternal dietary therapy at various stages of pregnancy is not known.

OBJECTIVE

To determine whether dietary treatment during pregnancy of women with PKU affects developmental outcomes of offspring.

DESIGN

The Maternal PKU Collaborative Study, an ongoing, longitudinal prospective study begun in 1984.

SETTING

A total of 78 metabolic clinics and obstetrical offices in the United States, Canada, and Germany.

PARTICIPANTS

A total of 253 children of women with PKU (n = 149), with untreated mild hyperphenylalaninemia (n = 33), or without known metabolic problems (comparison group; n = 71) were followed up to age 4 years.

INTERVENTION

Women with PKU were offered a low-phenylalanine diet prior to or during pregnancy with the aim of maintaining metabolic control (plasma phenylalanine < or =10 mg/dL [< or =605 micromol/L]). Women with mild hyperphenylalaninemia, who had plasma phenylalanine levels of no more than 10 mg/dL (605 micromol/L) on a normal diet, were not treated.

MAIN OUTCOME MEASURES

Children's scores on cognitive and behavioral assessments (McCarthy Scales of Children's Abilities, Test of Language Development, Achenbach Child Behavior Checklist, Vineland Adaptive Behavior Scales, and Home Observation for Measurement of the Environment), compared by maternal metabolic status at 0 to 10 weeks', 10 to 20 weeks', and after 20 weeks' gestation.

RESULTS

Scores on the McCarthy General Cognitive Index decreased as weeks to metabolic control increased (r = -0.58; P<.001). Offspring of women who had metabolic control prior to pregnancy had a mean (SD) score of 99 (13). Forty-seven percent of offspring whose mothers did not have metabolic control by 20 weeks' gestation had a General Cognitive Index score 2 SDs below the norm. Overall, 30% of children born to mothers with PKU had social and behavioral problems.

CONCLUSIONS

Our data suggest that delayed development in offspring of women with PKU is associated with lack of maternal metabolic control prior to or early in pregnancy. Treatment at any time during pregnancy may reduce the severity of delay.

In vivo development of brain phosphocreatine in normal and creatine-treated rabbit pups

To study the effects of creatine (Cr) on brain energy metabolism and on hypoxia-induced seizures, 5- to 30-day-old rabbit pups were given subcutaneous Cr (3 g/kg) for 3 days before exposure to 4% O2 for 8 min. In saline-treated controls, hypoxic seizures were most frequent at 15 days (80% of pups) and 20 days (60%) of age. Seizures were prevented at 15 days and reduced 60% at 20 days in Cr-treated pups. In surface coil-localized brain 31P nuclear magnetic resonance spectra, with signal from both cerebral gray (GM) and white (WM) matter, the phosphocreatine (PCr)/nucleoside triphosphate (NTP) ratio doubled between 5 and 30 days of age in controls. In all Cr-injected pups, brain PCr/NTP increased to values seen in 30-day-old controls. When spectra were acquired in predominantly GM and WM slices in vivo, the PCr/NTP ratio was very low in GM at 5 days but reached adult levels by 15 days in controls. In WM, the ratio increased steadily from 5 to 30 days of age. In Cr-injected pups, PCr/NTP increased to mature levels in WM and in GM at all ages. In conclusion, hypoxic seizures occur midway in the time course of brain PCr/NTP increase in rabbit pups as previously described in rat pups. In both altricial pups, systemic Cr increases brain PCr/NTP ratio and prevents hypoxic seizures. These results suggest that mature levels of PCr and/or Cr in brain limit EEG activation either directly or indirectly by preventing hypoxic metabolic changes.

Investigation of the possible associations between fluorosis, fluoride exposure, and childhood behavior problems

PURPOSE

This study investigated the potential association between fluoride exposure and behavior problems in children, as well as the prevalence of and risk factors for fluorosis.

METHODS

Children between the ages of 7 and 1 years (N = 197) were included in the study and were examined for dental fluorosis using the Modified Dean's Index. Parents of subjects completed and returned three questionnaires which investigated their children's history of exposures to fluoride, social and medical backgrounds, and behavior using the Child Behavior Checklist (CBCL).

RESULTS

Sixty-nine percent of the study participants demonstrated fluorosis with very mild fluorosis being the most common (39%), while 13% demonstrated moderate to severe fluorosis. Using a summation of the Modified Dean's index (Sum of 8), we divided the children into high fluorosis (HF) and low fluorosis (LF) groups. These groups were compared to each other with respect to fluoride exposures and behavior.

CONCLUSION

Although there was no association between the fluoride exposures in aggregate and fluorosis, there was a significant association between supplemental fluoride exposure from ages 0-3 years and fluorosis. There was no association between behavior problems and dental fluorosis in this population.

In vivo phosphocreatine and ATP in piglet cerebral gray and white matter during seizures

The creatine kinase (CK) reaction is thought to be important in coupling ATP metabolism and regulating ADP concentration in tissues with high and variable ATP turnover, including cerebral gray matter (GM). There is low phosphocreatine (PCr), low CK reaction rates, and high mitochondrial CK (MiCK) isoenzyme activity in GM compared to white matter (WM). To compare the CK reaction in GM and WM when ATP metabolism is high, CK reactants and reaction rates were measured in predominantly GM and WM slices in vivo in 2 and 14-day old piglets during pentylenetetrazole (PTZ) seizures using 31P nuclear magnetic resonance (NMR) 1-dimensional chemical shift imaging (CSI). Arterial pressure, temperature, and blood gasses were stable at both ages. Before seizures, the PCr/nucleoside triphosphate (NTP) ratio was higher in WM than GM at both ages with a developmental increase seen in WM. The CK reaction rate constant increased in both regions between 2 and 14 days. During seizures, PCr/NTP increased in GM at 14 days due to increased PCr while the ratio and PCr decreased in WM. The NTP was more stable in WM and GM at both ages. The CK reaction rate decreased in both regions more at 2 than at 14 days. Thus, brain ATP, deduced from NTP, is stable during seizures in the piglet. In GM stable ATP is associated with a unique increase in PCR concentration.

Neonatal neurological assessment of offspring in maternal phenylketonuria

This study assesses the impact of prenatal and postnatal factors in maternal phenylketonuria (PKU). The Dubowitz Neurological Assessment of the Preterm and Full-term Newborn Infant was administered within the first 8 days of life to 56 offspring of women with PKU and 45 controls. Follow-up testing of the maternal PKU offspring at age 1 year consisted of the Bayley Scales of Infant Development and the Receptive-Expressive Emergent Language Scale (REEL). In addition, the Home Observation for Measurement of the Environment (HOME Scale) was given. Birth weight was lower (z = 2.0, p = 0.045), birth length was lower (z = 2.1, p = 0.03) and birth head circumference was smaller (z = 3.5, p = 0.0005) in the maternal PKU offspring than in the control infants. Examiners rated 29% of the maternal PKU offspring and 9% of the control infants abnormal (Fisher's exact test, p = 0.01). At 1 year of age, 19% of the maternal PKU offspring attained a Bayley Developmental Quotient (DQ) and a score on the Bayley Motor Scale below 85; 19% had receptive language delay; and 26% had expressive language delay. The gestational age at which the mother attained metabolic control was an important factor associated with birth measurements, the Dubowitz Rating and subsequent developmental scores. The Dubowitz Neurological Assessment score did not predict developmental outcome (chi-square = 1.3, p = 0.53), while the HOME score correlated with the DQ (r = 0.36, p = 0.02). In logistic regression analyses, the home environment was a greater determinant of risk for a low DQ than whether or not the mother attained metabolic control prior to pregnancy (OR = 0.85, p = 0.02). These results suggest that treatment strategies addressing both prenatal and postnatal factors will most effectively reduce risks in maternal PKU.

Tobacco and alcohol use behaviors portrayed in music videos: a content analysis

OBJECTIVES

Music videos from five genres of music were analyzed for portrayals of tobacco and alcohol use and for portrayals of such behaviors in conjunction with sexuality.

METHODS

Music videos (n = 518) were recorded during randomly selected days and times from four television networks. Four female and four male observers aged 17 to 24 years were trained to use a standardized content analysis instrument. All videos were observed by rotating two-person, male-female teams who were required to reach agreement on each behavior that was scored. Music genre and network differences in behaviors were analyzed with chi-squared tests.

RESULTS

A higher percentage (25.7%) of MTV videos than other network videos portrayed tobacco use. The percentage of videos showing alcohol use was similar on all four networks. In videos that portrayed tobacco and alcohol use, the lead performer was most often the one smoking or drinking and the use of alcohol was associated with a high degree of sexuality on all the videos.

CONCLUSIONS

These data indicate that even modest levels of viewing may result in substantial exposure to glamorized depictions of alcohol and tobacco use and alcohol use coupled with sexuality.

In vivo brain phosphocreatine and ATP regulation in mice fed a creatine analog

Mitochondrial and cytosolic creatine kinase (CK) isozymes are active in cells with high and variable ATP metabolic rates. beta-Guanidinopropionic acid (GPA), a competitive inhibitor of creatine transport, was used to study the hypothesis that the creatine-CK-phosphocreatine (PCr) system is important in regulating brain ATP metabolism. The CK-catalyzed reaction rate and reactant concentrations were measured in vivo with 31P nuclear magnetic resonance spectroscopy during energy deficit (hypoxia) or high-energy turnover (seizures) states in urethane-anesthetized mice fed GPA, creatine, or standard chow (controls). Brain phosphagen (i.e., cellular energy reserves) or PCr plus phosphorylated GPA (GPAP) concentrations were equal. The phosphagen-to-NTP ratio was lower than in controls. In vivo CK reaction rate decreased fourfold, whereas ex vivo CK activity that was biochemically measured was doubled. During seizures, CK-catalyzed fluxes increased only in GPA-fed mice. Phosphagen increased in GPA-fed mice, whereas PCr decreased in controls. Survival was higher and brain phosphagen and ATP losses were less for hypoxic GPA-fed mice than for controls. In contrast to mice fed GPA, hypoxic survival and CK reactant concentrations during hypoxia and seizures were the same in creatine-fed mice and controls. Thus GPA, GPAP, or adaptive changes in ATP metabolism stabilize brain ATP and enhance survival during hypoxia in mice.

Alveolar bone height of primary and first permanent molars in healthy seven- to nine-year-old children

The purpose of the study was to establish baseline values of the alveolar bone height of the primary molars and first permanent molars in sample of healthy U.S. seven- to nine-year-old children. Direct measurements of the distance from the cementoenamel junction (CEJ) to the alveolar crest (AC) on 223 pairs of bitewing radiographs from 223 subjects were made using a digimatic caliper under standardized conditions. The distance from the CEJ to the AC had medians from 0.58 mm to 1.39 mm (range 0.0 to 4.44 mm) for the primary molars and from 0.00 mm to 0.64 mm (range -1.35 to 2.15 mm) for the mesial aspect of the permanent molars. There were no statistically significant differences in the distance from CEJ to AC between teeth on the right and left sides of the mouth. The distances from CEJ to AC were always greater in the maxilla than in the mandible for similar primary molar sites, but only true for the mesial aspect of the permanent first molar at age nine. As a tooth is positioned more anteriorly in the mouth, the distance from CEJ to AC was greater. On the whole, males had greater distances than females and eight-year-olds had larger distances than seven- or nine-year-olds. Differences were observed in the measured distances for the different age and sex-groups and may be attributable to variations in eruption and exfoliation patterns. The distance was significantly greater in areas of interproximal restorations and open contacts, and there was a tendency for the distances to be greater in areas of interproximal caries.

Violence and weapon carrying in music videos. A content analysis

BACKGROUND

The positive portrayal of violence and weapon carrying in televised music videos is thought to have a considerable influence on the normative expectations of adolescents about these behaviors.

OBJECTIVES

To perform a content analysis of the depictions of violence and weapon carrying in music videos, including 5 genres of music (rock, rap, adult contemporary, rhythm and blues, and country), from 4 television networks and to analyze the degree of sexuality or eroticism portrayed in each video and its association with violence and weapon carrying, as an indicator of the desirability of violent behaviors.

METHODS

Five hundred eighteen videos were recorded during randomly selected days and times of the day from the Music Television, Video Hits One, Black Entertainment Television, and Country Music Television networks. Four female and 4 male observers aged 17 to 24 years were trained to use a standardized content analysis instrument. Interobserver reliability testing resulted in a mean (+/- SD) percentage agreement of 89.25% +/- 7.10% and a mean (+/- SD) kappa of 0.73 +/- 0.20. All videos were observed by rotating 2-person, male-female teams that were required to reach agreement on each behavior that was scored. Music genre and network differences in behaviors were analyzed with chi 2 tests.

RESULTS

A higher percentage (22.4%) of Music Television videos portrayed overt violence than Video Hits One (11.8%), Country Music Television (11.8%), and Black Entertainment Television (11.5%) videos (P = .02). Rap (20.4%) had the highest portrayal of violence, followed by rock (19.8%), country (10.8%), adult contemporary (9.7%), and rhythm and blues (5.9%) (P = .006). Weapon carrying was higher on Music Television (25.0%) than on Black Entertainment Television (11.5%), Video Hits One (8.4%), and Country Music Television (6.9%) (P < .001). Weapon carrying was also higher in rock (19.8%) and rap (19.5%) videos than in adult contemporary (16.1%), rhythm and blues (6.9%), and country (6.3%) videos (P = .002). The videos with the highest level of sexuality or eroticism were found to be less likely to contain violence (P < or = .04).

CONCLUSION

Because most music videos are between 3 and 4 minutes long, these data indicate that even modest levels of viewing may result in substantial exposure to violence and weapon carrying, which is glamorized by music artists, actors, and actresses.

Spectrum of tumor angiogenesis in the bone marrow of children with acute lymphoblastic leukemia

It has been shown that solid tumors progress in concert with an induction of tumor angiogenesis. It is not known, however, whether a similar phenomenon occurs in leukemia. Angiogenesis was characterized immunohistochemically by factor VIII staining of bone marrow biopsies and quantified by assessment of microvessel density using previously described techniques. We evaluated bone marrow biopsies from 40 children with newly diagnosed, untreated acute lymphoblastic leukemia. In 22 of the patients, we also evaluated angiogenesis after the completion of remission induction chemotherapy. Control specimens were obtained from children undergoing staging evaluations at the time of diagnosis of solid tumors and lymphomas. Microvessels were counted throughout the entire core specimen in consecutive x 200 fields, and a median count per field (cpf) was calculated. In addition, the number of microvessels in the single x 200 field with the highest microvessel density was designated as the "hot spot." Biopsies from children with leukemia and from controls showed median microvessel densities of 42 and 6 counts per field, respectively (P < or = 0.0001). Microvessel density of the hot spots of leukemia specimens and controls were also significantly different, 51 and 8, respectively (P < or = 0.0001). A computer-aided three-dimensional reconstruction model of bone marrow vascularity showed a complex, arborizing branching of microvessels in leukemic specimens compared with single, straight microvessels without branching in controls. Urinary basic fibroblast growth factor, a potent angiogenic factor, was measured in 22 of the children with newly diagnosed leukemia and in 39 normal, age-matched controls. Urinary basic fibroblast growth factor levels were increased in all 22 patients before treatment, were variable during induction chemotherapy, and demonstrated statistically insignificant decreases at the time of complete remission. These findings suggest that leukemia cells induce angiogenesis in the bone marrow and that leukemia might be angiogenesis dependent and raise the possibility for a role of antiangiogenic drugs in the treatment of leukemia.

Effect of cholesterol reduction on myocardial ischemia in patients with coronary disease

BACKGROUND

Cholesterol lowering is associated with a reduction in cardiovascular morbidity and mortality. This study sought to determine whether cholesterol lowering also results in a reduction of myocardial ischemia during daily life.

METHODS AND RESULTS

We enrolled 40 patients with proven coronary artery disease, total serum cholesterol between 191 and 327 mg/dL, and at least one episode of ST-segment depression on ambulatory ECG monitoring. Twenty patients were randomized to an American Heart Association Step 1 diet plus placebo (placebo group) and 20 to the same diet plus lovastatin (treatment group). Serum cholesterol and LDL cholesterol levels and ambulatory monitoring were repeated after 4 to 6 months of therapy. The two groups were comparable with respect to baseline characteristics, number of episodes of ST-segment depression, and baseline serum cholesterol levels. The treatment group had lower mean total and LDL cholesterol levels at study end and experienced a significant reduction in the number of episodes of ST-segment depression compared with the placebo group. ST-segment depression was completely resolved in 13 of 20 patients (65%) in the treatment group versus 2 of 20 (10%) in the placebo group. The treatment group exhibited a highly significant reduction in ischemia (P < .001). By logistic regression, treatment with diet and lovastatin was an independent predictor of ischemia resolution.

CONCLUSIONS

Cholesterol lowering with lovastatin appears to be effective in eliminating myocardial ischemia during daily life in a significant proportion of patients.

Maternal non-phenylketonuric mild hyperphenylalaninemia

Unlike maternal phenylketonuria (PKU) which produces severe birth defects when untreated during pregnancy, maternal non-PKU mild hyperphenylalaninemia (MHP) has a less severe impact but whether it is benign or may have long-term consequences for offspring has been unclear. From an international survey of maternal MHP we obtained information about 86 mothers (blood phenylalanine (Phe) 150-720 mumol/l), their 219 untreated pregnancies and 173 offspring. Spontaneous fetal loss and congenital anomalies were no more frequent than normally expected. Median Z-scores for birth length and birth head circumference and offspring IQ (100), however, were significantly lower for maternal Phe > 400 mumol/l than for maternal Phe < 400 mumol/l, in which the median offspring IQ was 108. Data on maternal MHP from the prospective Maternal PKU Collaborative Study (MPKUCS) are as yet incomplete but seem to be conforming to the general pattern of the international survey. We conclude that maternal blood Phe levels above 400 mumol/l in maternal MHP are associated with lower birth measurements and slightly lower offspring IQ. It would seem that dietary intervention to lower the maternal Phe levels to below 400 mumol/l might be indicated in maternal MHP pregnancies with the higher blood Phe levels.

Phosphocreatine and ATP regulation in the hypoxic developing rat brain

Decreased brain ATP and phosphocreatine (PCr) concentrations and intracellular pH were compared in hypoxic 4-, 10-11, and 24-25-day-old rats. Surface coil 31P-nuclear magnetic resonance (NMR) spectra were acquired in vivo every minute before, during, and after 7 min of breathing 4% O2. At all ages PCr decreased rapidly. At the two younger ages, the nucleoside triphosphate signal was still 80-85% of pre-hypoxic values, indicating 20-30% decrease in ATP, when PCr was almost fully depleted. At 24-25 days, PCr initially decreased 40-50% with an ATP loss of about 30%. Then, PCr and ATP decreased simultaneously. The decrease in brain pH was greatest at 24-25 days. More electrocortical seizure activity during hypoxia was seen at 10-11 days than at other ages. Seizure activity was seen only when ATP was less than 20% depleted and was not associated with more rapid decreases in ATP or PCr. At all ages, loss of electrocortical activity occurred when ATP was about 30% depleted. Brain creatine kinase catalyzed flux, measured by the NMR saturation transfer experiment before the hypoxic period, was 4-fold higher at 24-25 days than at 4- or 10-11 days. In conclusion, the temporally coupled depletion of PCr and ATP during hypoxia, which is characteristic of the mature brain, is seen only after the maturational increase in brain CK activity.

Maternal mild hyperphenylalaninaemia: an international survey of offspring outcome

Maternal phenylketonuria (PKU) has adverse effects on the offspring including microcephaly, mental retardation, congenital heart disease, and intrauterine growth retardation. Maternal non-PKU mild hyperphenylalaninaemia (MHP) is believed to be benign, but whether there may be long-term consequences to offspring is unclear. In an international survey we have obtained information about 86 mothers with MHP (blood phenylalanine 167-715 mumol/L), their 219 untreated pregnancies, and 173 offspring. Spontaneous fetal loss (13% of pregnancies), congenital heart disease (2.3% of offspring), and severe non-cardiac anomalies (2.9% of offspring) occurred at frequencies within expected limits for the general population. For weight and length at birth the median percentile was the 50th but that for birth head circumference was the 25th. Median z-scores for birth length and head circumference were significantly lower for offspring of mothers with phenylalanine concentrations above 400 mumol/L than for those whose mothers had lower values (p = 0.05 and p = 0.005, respectively). The median intelligence quotient (IQ) of the offspring (3-27 years) was 100 for those whose mothers had higher phenylalanine concentrations and 108 for those of the lower phenylalaninaemia group. However, offspring IQ correlated slightly more closely with maternal IQ (r = 0.53, p < 0.001) than with maternal phenylalanine concentration (r = 0.45, p = 0.02). Maternal MHP does not seem to have serious consequences for the fetus. A maternal phenylalanine concentration of less than 400 mumol/L does not warrant intervention. Nevertheless, maternal blood phenylalanine above this value is associated with slightly lower birth measurements and offspring IQ than lower maternal blood phenylalanine concentrations.

Pre- and postnatal lead exposure and behavior problems in school-aged children

The association between early lead exposure and later problem behaviors was evaluated prospectively in a cohort of 8-year-old children born during a 12-month period at one hospital. Lead levels in umbilical cord blood (means = 6.8 micrograms/dl, SD = 3.1) and the dentin of a shed deciduous tooth (means = 3.4 micrograms/g, SD = 2.4) provided measures of prenatal and postnatal exposure, respectively. Ratings on the Teacher Report Form of the Child Behavior Profile provided information about children's problem behaviors. Cord blood lead level was not associated with the overall prevalence or nature of problem behaviors. In both crude and adjusted analyses, tooth lead level was significantly associated with total problem behavior scores (approximately 2 points in T score per log unit increase in tooth lead). Significant tooth lead-associated increases in both internalizing and externalizing scores were also observed (approximately 1.5 points in T score per log unit increase). Weaker associations were noted between tooth lead level and the prevalence of "extreme" problem behavior scores. The extent to which these associations reflect residual confounding is uncertain. These data suggest, however, that social and emotional dysfunctions are correlates and may be expressions of increased lead exposure.

The Boston Teacher Questionnaire. 3. A reassessment

The prevalence of different types of dysfunction in school was assessed with the Boston Teacher Questionnaire, completed for 1923 children born 8 years earlier in a university-affiliated maternity hospital. Cluster analyses of 15 items on the questionnaire resulted in six two-item clusters and one three-item cluster that were identical for girls and boys. We identified children as having a syndrome if they possessed all features of the cluster-defined syndrome. The most prevalent syndrome, consisting of both daydreaming and distractibility items, occurred in 18.5% of boys and 11.5% of girls. Boys were also more likely than girls to be identified as having the reading syndrome (11.6% and 7.7%, respectively), the hyperactivity/impulsivity syndrome (6.1% and 1.5%), and the syndrome characterized by frustration intolerance and peer problems (9.5% and 4.0%). The prevalences of the remaining three syndromes were similar in both sexes (arithmetic, 11.3% and 10.3%; difficulty following instructions, 5.1% and 4.7%; and the tasks syndrome [characterized by impersistence/dependence/inflexibility], 5.5% and 5.4%). More than 40% of boys and girls with one syndrome also had another. The lower prevalences in this sample than in an earlier-born sample assessed with the same instrument were confined to boys. Reasons for this temporal decrease in one sex only remain obscure. Girls with the reading syndrome were 10 times more likely, and boys with the reading syndrome were five times more likely, than their peers to receive special services and to have repeated a grade.

Antecedents and correlates of hypoplastic enamel defects of primary incisors

Four hundred and fifty-five exfoliated primary incisors were obtained from children whose mothers provided information about a wide range of pre-, peri-, and postnatal characteristics of both the mother and child. These teeth then were examined for the presence of hypoplastic enamel defects (HED). The basic form of the null hypothesis tested was that children who had HED of a primary incisor did not differ from those who did not have such a defect. Of the primary incisors examined, 18.5% had HED (25.0% maxillary and 10.1% mandibular). The following items were found to be associated most strongly (P less than 0.003) with an increase in a child's risk of developing HED; 1) maternal antenatal history of smoking, higher prepregnancy weight, and failure to obtain prenatal care during the first trimester; 2) prematurity, low birth-weight and their associated correlates; and 3) postnatal measles infection. Left-handedness, maternal tea and Tylenol (McNeil Consumer Products Co., Fort Washington, PA) consumption, and failure to screen for undue lead burden were associated less prominently (P less than 0.05) with HED prevalence. Season of birth and serum and dentin lead levels were not related to the prevalence of HED. Many of these risk factors are also covariates of low socioeconomic status such as suboptimal nutrition and increased risk of infection. Additional investigation is needed to delineate the associations between specific pre- and perinatal nutritional and infectious factors, socioeconomic status, and HED development.

Pre-natal blood lead levels and learning difficulties in children: an analysis of non-randomly missing categorical data

This paper presents an analysis of categorical variables subject to non-response. We incorporate the incomplete data into the analysis by modelling the distribution of the variables of interest and the non-response mechanism. We discuss issues of model selection and interpretation and the effect of discarding incomplete observations. In addition, we describe how to perform all of the computations with standard statistical software. We discuss the problem of incomplete categorical data within the context of a study of the effect of lead exposure on learning difficulties in children. In this study, many of the children are not observed on some of the variables of interest. It is particularly important in this study to incorporate the incomplete data, since there is evidence that non-response is related to the variables of interest. We reach different conclusions when we incorporate the incomplete data into the analysis than we reach when we discard the incomplete data. We also examine the sensitivity of our conclusions to the choice of a model for the non-response mechanism.

Macroscopic enamel defects of primary anterior teeth--types, prevalence, and distribution

A total of 40.7% of 509 exfoliated primary anterior teeth from children who were healthy products of uneventful pregnancies exhibited at least one macroscopic enamel defect. Twenty percent of the teeth exhibited hypoplastic defects (HD), 12.4% exhibited white-cream opacities (WCO), and 9.8% exhibited yellow-brown opacities (YBO). Slightly more than a third (33.6%) of the teeth had defects we considered to be developmental enamel defects (DED). The occurrence of DED did not vary with gender, side of mouth, individual tooth types, or racial background. DED occurred with increased frequency on maxillary teeth, facial surfaces, and the middle third of affected surfaces. These locations have thicker enamel than other sites and may be more susceptible to insult if vulnerability is a function of metabolic demand of the rapidly secreting ameloblasts. Twenty-five per cent of the maxillary incisors and 10.1% of the mandibular incisors exhibited HD whose locations coincided with enamel forming at birth. A third (33.3%) of the canines exhibited HD, which occurred most commonly in the middle third of the facial surfaces. These defects are believed to occur approximately six months postnatally and may be primarily due to mechanical trauma. YBO most commonly occurred on the middle third of the facial surfaces, while WCO on the gingival third. Neither YBO nor WCO followed a chronologic pattern.

Effect of chewing rawhide and cereal biscuit on removal of dental calculus in dogs

The effect of chewing rawhide and cereal biscuit on removal of dental calculus was studied in 67 dogs. Two methods were used to measure supragingival calculus and calculus removal as a function of time and acceptability. Trial 1 used a quantitative method based on actual measurement of the area of calculus on a tooth, and trial 2 used a quantitative method based on an arbitrary grading system to establish a supragingival calculus index. Analysis was performed, using 2-factor (trial 1) and a 3-factor (trial 2) analysis of variance. Results indicated that dogs removed calculus from their teeth by chewing rawhide; some teeth were cleaned better than others. The optimal amount or frequency of rawhide treatment was not necessarily determined. It was determined that regular consumption of up to 3 rawhide strips/d for 3 weeks was safe. Processed biscuits were sometimes effective in removing calculus from dog's teeth; however, biscuits were not as effective as the rawhide in removing supragingival calculus.

Fifteen-year experience with 1678 Hancock porcine bioprosthetic heart valve replacements

The Hancock porcine valve was the first commercially available biologic heart valve and has been in continuous use at the Brigham and Women's Hospital since January 1972. Through December 1987 we implanted 1678 valves in 1533 patients (885 male; 648 female; 17 to 95 years of age, with a mean of 60 years). There were 825 aortic valve replacements (AVR), 562 isolated mitral valve replacements (MVR), and 146 aortic mitral replacements (DVR). Ninety-four per cent of the patients were functional class III or IV. Associated coronary bypass was done in 25% of patients. Four per cent of patients were lost to follow up during a 1- to 16-year period with a mean of 6 years. Morbidity and mortality rates on a actuarial basis were calculated 10 and 15 years after operation for AVR, MVR, and DVR. The data indicates that the probability of reoperation for structural valve failure is quite reasonable as of 10 years, but from 10 to 15 years the numbers sharply fall off so that the probable effective life of the valve is 10 years. However in the elderly age group (equal to or greater than 70 years of age) the incidence of structural valve degeneration is markedly diminished, making this an ideal valve substitute for the elderly. It is also an ideal valve substitute in any patient who has a contraindication to long-term anticoagulation because of current medical or surgical problems.

Hemorrhage, phenobarbital, and fluctuating cerebral blood flow velocity in the neonate

Fifty-one sequential intubated babies with birth weights of less than 1,751 were evaluated by serial Doppler ultrasound during the first three days of life. These babies were part of a phenobarbital prophylaxis trial cohort study. Subependymal-intraventricular hemorrhage developed in 17 of the babies. Infants with subependymal-intraventricular hemorrhage, whether or not they received pancuronium or phenobarbital, had coefficients of variation comparable to those of babies without hemorrhage. Coefficient of variation values of the right were comparable to values obtained from the left anterior cerebral artery complex and did not appear to be consistently altered by the presence of subependymal-intraventricular hemorrhage. Coefficient of variation values appeared to be consistently greatest on day 1 and lowest on day 2. In addition, the values overall increased as the number of waves used to determine the coefficient of variation enlarged from five to 20. This phenomena, however, was not seen among pancuronium recipients and suggests that movement artifact may be a determinant of coefficient of variation values. We conclude that, when the best 20 waves are chosen to evaluate the coefficient of variation, no association exists between coefficient of variation values and development of subependymal-intraventricular hemorrhage or administration of phenobarbital.

Respiratory complications in low-birth-weight infants who received phenobarbital

We compared the ventilatory requirements of 127 infants who received phenobarbital for five days with those of 111 infants who received placebo. All infants were intubated, weighted less than 1750 g at birth, and survived the first ten days of life. Those infants who received phenobarbital did not require ventilatory assistance for more days than did placebo receivers. However, a pneumothorax or pulmonary interstitial emphysema was more likely to develop in infants who received phenobarbital than in infants who received placebo, even when adjustment was made for the presence of subependymal-intraventricular hemorrhage. We believe this is the first report of this relationship and recommend additional studies to test the hypothesis that phenobarbital contributes to the occurrence/recognition of pneumothorax or pulmonary interstitial emphysema in very-low-birth-weight infants if phenobarbital continues to be used routinely as prophylaxis or treatment.